Megaptera novaeangliae) males in a population sing fundamentally the same version of a complex, progressively changing, series of sounds at any one time – the song. The purpose of this study was to describe the relationship of humpback whale populations across the North Pacific based on song composition. Songs were collected from Philippines, Japan, Hawaii and Mexico in 2011, 2012 and 2013. The presence and proportion of 11 phrase types were compared within and between populations to investigate song similarity and change. Results included: shared song phrases across the North Pacific; variable, temporary, regional song differences; varying rate of song change; and distance a factor, but not predictor in degree of similarity. Shared phrases indicate ongoing mixing of populations throughout the North Pacific. Year to year differences in degree of similarity suggest variability in these interactions. Songs appear to diverge as populations split up and converge when they amalgamate. Song studies complicate current US management policy designating four distinct populations in the North Pacific. North and South Pacific humpback whale population structure may be comparable, although song dynamics may be different. The fluidity of song composition suggests it provides acoustic definition or identity to changing associations of whales.All humpback whale ( Megaptera novaeangliae) males repeat loud, long (5–20 min), complex sequences of sounds known as song2. Singing is largely but not exclusively seasonal, its occurrence increasing in fall feeding grounds, peaking during winter migrations and assembles, and decreasing in the spring8. Its function is not known but is generally presumed to play a role in breeding activities14.Humpback whale  changes, yet all the singers in one population sing fundamentally the same version at any one time18. Since then, further song comparisons in the North Pacific23 and worldwide28 have, at least, inferred that the similarity or difference in songs is a reflection of the degree of population mixing.The practical application of these song characteristics to define humpback whale populations has been proposed since the late 1970s with the first comparisons of songs between Mexico and Hawaii29. This action divided the North Pacific population into four “Distinct Population Segments” (DPSs) based on winter assemblies, regardless of multiple studies indicating similarity of song23.However, to date the song has not been widely recognized as a means of population definition in humpback whale management. In fact, a recent regulatory action under the Endangered Species Act  by U.S. National Oceanic and Atmospheric Association (NOAA)/National Marine Fisheries Service (NMFS) ignored songs entirely, with the declaration of population units based on “genetic data, tagging and photographic-ID data, demographic information, geographic barriers and stranding data”11. If, indeed, the song functions as a signal of association on a population level, could the same song dynamic work on a smaller scale and provide an identity to smaller groups, or even individuals?Beyond potential human use of song to distinguish whale populations is the question of whether or not it serves a similar function for the whales, that is, the identification of recent associatesBoth management-use issues and the study of song function come down to the same question: does the degree of song similarity correlate with degree and/or immediacy of interaction? Or, as a hypothesis: on any scale, whales that are more associated – that is, engage in more interactions – should have a more similar song than those that are lesser associated.23. This earlier study compared locations in the Philippines, Japan and Hawaii. Consistent with the hypothesis, the songs of the two geographically closer locations (Philippines and Japan) were more similar than when compared with songs from the more distant Hawaii. The finer the song characteristics examined, the more definable any temporarily isolated population was. However, overshadowing these real but relatively small differences apparent over this single season was the marked similarity of songs from Hawaii and Asia, and this, combined with past Hawaii-Mexico studies21, suggested mixing of humpback whales throughout the Pacific. While a notable ocean-wide similarity in songs existed, smaller scale differences apparently reflected the degree of separation of populations.This current study expands on an initial investigation into this question undertaken in 2006 with a “snapshot” comparison from three locations over a single seasonThe purpose of the current study then was two-fold. First, to further investigate the interaction and identity of humpback whale populations in the North Pacific based on song composition; and second, to examine how these results might contribute to investigation of the function of the song.30. The distances between the locations and the humpback whale populations compared are provided in Fig. The study locations were in four regions as shown in Fig. The objective was to record multiple singers, in all locations, over as much of the winter season as possible in each of these three study years. The total sample from each region in each year varied with field circumstances, including duration of study, weather, equipment issues and whale presence. Samples were collected directly from small (7–10 m) craft with dipping hydrophones. A singer was located acoustically, and often visually; the boat maneuvered until the signal was strong and the song was recorded.Recording equipment varied between locations, but all were professional quality digital recorders and hydrophones as follows: Philippines, Zoom H4N recorder with DolphinEAR Pro hydrophone; Japan, in 2011–12, SONY DAT Walkman TCD-D50 and in 2013, SONY Linear PCM Recorder PCM-D50, with HTI-96-min hydrophone; Hawaii, Marantz 620 with HTI-9-min hydrophone; Mexico: Baja, Marantz PMD 660 with HTI-96-min hydrophone, and Banderas Bay, in 2011, Sony Hi-MD recorder (MZ-M200) with Offshore Acoustics omnidirectional hydrophone, in 2012–13, a Fostex FR2 Field recorder with Cetacean Research Technology directional hydrophone (C304). All songs were recorded in wav format with a sampling rate of 44.1 kHz or higher, with the exception of two of the four 2011 Philippine songs recorded as MP3 files .All recordings of at least 20 minutes duration, or that clearly included one full song cycle  were graded for clarity. The quality was assessed subjectively by the principle investigator (JD) – the only criteria being that all components of the song were clear, both aurally and visually on spectrograph. The lowest grade used in analysis was ‘C+’, which signified recordings with ‘moderate background noise  but with all sound units recognizable. The majority of recordings were ‘A’ quality with a strong signal and quiet background. The song samples used in this analysis, including combined length of recordings, number of singers, and date span of recordings, are summarized in Table all recordings that met the criteria of length and quality were included, both full song and fragments. The reasons for this were: (1) it was not always obvious in recordings where the ‘beginning’ and ‘end’ of the song cycle was. Some whales surfaced and dove mid-song, that is between the most common first and last phrases; and, in fact, some did not include first and last phrases in a cycle; and, (2) one purpose of this analysis was to obtain as full a representation as possible of all phrase types in a population, including those which may have occurred even once in a fragment of a song. Analyses within this study determined if a pattern was common or rare.Recordings from each singer ranged from the length of one song cycle (the shortest at 9 min 20 s) to an hour or longer and over several song cycles. Some recordings also included partial songs when the recorder was turned on or off mid-song. In this analysis, 1 and used by most authors since31. Terms are summarized in Table parent phrase and unit flourish as defined below  with terms first described in 1971ow Table , and in Recordings were examined aurally and with spectrograph (using Avisoft-SASLab Pro and Raven Pro 1.5 software) to identify and define phrase types; examples provided in Supplementary Fig. Phrases were the primary unit of comparison between locations and years. However, in this 2011–2013 sample of songs one phrase was more complex than the others, and was divided into four sub-patterns described in Results. The presence and proportion of these sub-patterns were also used as comparison points.The analysis consisted of determining if a specific phrase type  was present in a recording and, if so, how common (percentage of sample) it was. For the latter, all individual song recordings in each location/year were combined as a ‘population sample’. In this total sample the amount of time (seconds) dedicated to each Phrase Type was determined, and its proportion stated as a percent.  were highly distinctive points of comparison. However, continual, gradual song change over the study period, and individual singer variation across a sample required decisions on: (1) the splitting or clumping of relatively minor variations in phrase types; (2) defining when one phrase type changed enough to be called a different phrase type; and (3) resolution of sound patterns inconsistent or exceptional to the norm. These decisions were made after the initial assessment of the data, and then applied consistently throughout the analyses. More detail on these decisions is included in the Supplementary Methods − Analysis Decisions, and in Supplementary Table Results of the broader analysis led to two other small explorations of the data. The 2013 Japan song sample was divided into early and late season and these halves compared to more accurately illustrate song changes within this one season.To provide some context for the  Mexico  2011 song, songs from Mexico and Hawaii in 2010, the year prior to this study, were examined.n values of 4 and 3), statistical analyses were limited. However, once the presence and percent occurrence of each phrase type was determined, Pearson’s Correlation Coefficient was applied between song samples providing an index of similarity between years in one location, and between the four locations in each year. Additionally, regression analyses provided a measure of degree of song similarity (using simple presence or absence of a  phrase type) versus geographical distance of separation.With the comparisons of representative songs from four locations over three years,  as well as finer divisions of the more complex Phrase 4. Phrase 4 was divided into the parent (4a) and two variants . The parent phrase 4a was further divided into ‘simple’ (4a) versus ‘flourish’ (4aF) versions.  were identified in all four locations across the span of the Pacific; seven phrases were found in three of the four; and all 11 found in two of the four locations at some point within the three-year period as shown in Table There were, within the three-year span, year-to-year differences in both total phrases in a population (as phrase types appeared and disappeared), and in the percentage of these shared between the North Pacific populations Table . The firBeyond simple presence there was a wide range in the proportion of a song cycle dedicated to a specific phrase. This analysis determined what percentage of the song was dedicated to each of the phrase types: 1, 2, 3, 4a, 4aF, 4b, 4c, 5, 6, 7, 8. The results are illustrated in the pie charts in Fig. The percentage of song cycle dedicated to any one phrase ranged from less than 1% to close to 80% (clumping variants), with some consistency in this value per phrase across all populations in a year. For example, Theme 4  represented the largest percentage of the song in all locations in all years, and comprised more than 50% of the song sample in 10 of 12 possible combinations of locations/years  dropped from, in 2011, 14% percent of the song in both Philippines and Japan and 2% in Hawaii; to, in 2012, 6%, 9% and 0% respectively; and in 2013, even lower to 2%, 3% and 0%. A more rapid decrease and disappearance of full phrases occurred in Mexico with Themes 7 and 8 occupying 20% and 25% of song in 2011; by 2012, this was down to 2% and 2%, and by 2013, both were at 0%. Other phrases maintained their presence and proportion over the three years , while new phrases appeared during the study period, such as Phrase 5 (pink), which progressed from 0% in 2011, to 2% in 2012, to 5% in 2013.Within the three years the amount of song change  from year to year was not a constant within a population. For example, the Philippines’ song showed virtually no change from 2011 to 2012 with a high correlation , and a greater change from 2012 to 2013 with weaker  between these years  and remained so with the pace of change increasing similarly in both populations.A similar pattern occurred in the Japan song with 2011 and 2012 highly correlated  and 2012 to 2013 with a much lower correlation   and from 2012 to 2013 songs . Over the three years from 2011 to 2013, Hawaii song changed least of the 4 locations . In contrast, the Mexico song showed a substantial change from 2011 to 2012  and again, from 2012 to 2013 . The Mexico song changed most in the three years with an inverse correlation value  between 2011 and 2013 songs. Over the three years, the Asia song changed more than Hawaii and less than Mexico  but, as discussed above, it changed unsteadily, with most of that change coming in the last year.In the three years of this study, the Mexico population was most ‘acoustically dynamic’, with correlations year to year of approximately 0.4 and 0.4, or roughly 60% of song change per year. In comparison, in Hawaii, the year-to-year correlations were 0.8 and 0.8 or 20% change per year. Asia, as described above, showed variability in this regard, ranging from a less than 10% to near 50% song change per year.Over the course of this study, the degree of similarity of songs between locations was not consistent year to year, and varied substantially Fig. . At theiIn 2011 Fig.  top row,In 2012  was shared across the entire North Pacific, in 2012, 3 of 8 (30%) phrase types were shared, and in 2013, 4 of 8 (50%) phrase types shared. Similarly, correlations between samples from the most distant populations progressed from inverse in 2011  to somewhat correlated in 2012 , to highly correlated in 2013 . The greatest divergence in songs across the North Pacific was in 2011, and the greatest convergence in 2013, with 2012 midstream between.The relationship between the degree of song similarity and distance between populations was investigated through: (1) linear regression analysis of the distances apart versus percentage of shared phrases, and (2) a comparison of distance apart using the Pearson’s Correlation Coefficient values of songs.2 values were all greater than 0.50, which indicated that distance apart was indeed a factor and could explain half to over three-quarters  of the variation in the percentage of shared theme values. However, these values also indicate that distance apart only partially explains the data.Linear regressions were performed to determine if there was any association of distance and percentage of shared themes for each year shown in Fig. A second view of this relationship is given in Table During the course of the Japan 2013 analysis, which included 12 singers recorded from January to April, a relatively greater degree of difference was noticed between early and late songs than in other samples. To examine this difference further, the season was divided into the first half’s (Jan./Feb.) six songs and second half’s (Mar/Apr.) six songs. As illustrated in Fig. The higher degree of uniqueness in the Mexico 2011 song relative to other years and locations led to further examination of its context. Three songs recorded in each of Hawaii and Mexico in 2010, the year previous to this study, were analyzed. As illustrated in Fig. 23; studies listed in Table Over at least 35 years (1977–2013) humpback whales in different North Pacific winter assemblies – in Mexico, Hawaii, Japan and Philippines − shared all, or portions, of complex, ever-changing songs18 reported Mexico and Hawaii sharing 55% of  phrases  in 1977, and 100% of phrases in 1979. It is apparent that in the North Pacific, the degree of song similarity (based on presence and proportion of different phrase types) reported between winter assemblies depends on the year the sampling was done, and may even depend on time of year, as indicated by the change in Japan 2013 song from early to late in season.However, this study showed that while the rule over time was a common ‘greater’ song across the North Pacific the percent of shared phrases between winter assemblies varied from year to year. This was immediately evident with these comparisons over three subsequent years; on review, earlier studies collectively indicate a similar pattern Table . For exavaried from small to substantial, these states were observed to be temporary – and reversible. Overall, song divergences were markedly limited relative to the potential of four or more completely different songs in the North Pacific. It is apparent that over an extended time period, regardless of temporary divergences, songs change collectively across the entire North Pacific.Rather than static or constant, the differences between winter assemblies may be better viewed as fluid divergences from a more common North Pacific song. While the degree of difference between assemblies The question is why the degree of song similarity varied year to year between winter populations with the same geographic spacing? The most likely explanation is that this variability was a reflection of a differing degree of interaction year to year of whales from the different winter assemblies. As hypothesized, more similar song would indicate greater mixing of whales while its divergence would indicate less mixing and extended periods of isolation.21. This suggests that isolation via distance led in short order towards song divergence. Conversely, song convergence was reported from Australia in 2000 when the mixing of previously isolated whales led to song conformity. In this case, whales in eastern Australia changed their song to match that of whales from western Australia, presumably due to an influx of whales from the west4.Hard evidence for this relationship is limited but developing. One study which compared Mexico and Hawaii 1999 songs reported small-scale but increasing song differences as the winter season progressedAccording to this construct, the low correlation of song in 2011 between Asia and Mexico, and even between Hawaii and Mexico would reflect a greater degree of isolation of the Mexico population prior to that season; and the high correlation of song in 2013 across the breadth of the North Pacific would indicate far more mixing had occurred prior to that date. It is important to acknowledge here that beyond the need to be within acoustic range, the actual location and season of song adoption or blending is unknown.4. Within this current study, the clearest potential example of an event-based change was in mid-season 2013 when the Asia song took a relatively rapid turn to greater similarity with songs from further east.The topic of the mechanism(s) of change in an individual’s and population’s song is complex and largely beyond the scope of this report, however two observations are notable. The first is that song change was not necessarily steady: characterized by periods of relative stability with spurts of greater change. This suggests that some North Pacific change is event-based, similar to when the western Australia singers rapidly changed eastern Australia song by intruding into the song pool33.The second insight is that different populations may have different sensitivity or propensity to change, an idea that will require a longer study to confirm. In this study, Mexico appeared more ‘acoustically dynamic’ (60% song change year to year) than Hawaii (20% song change year to year). Combined, these observations suggest song change may result from the interplay of (at least) two factors: the degree of exposure to different songs providing the raw material for change; and, the sensitivity of the current song to change, speculatively, a function of the number of new songs introduced relative to the size of pool of ‘pre-existing song’ whales. For example, perhaps ‘Mexico’ whales spread further in the summer than ‘Hawaii’ whales increasing exposure to a greater variety of songs, and/or may have a more complex distribution in winter that promotes song divergences, and as well have a smaller population or pool of singers than Hawaii, making change more likely28. Critically, however, this relationship between geographic distance and mixing is not a constant, or even a given, in the North Pacific. Other factors may override it in some years, resulting in broader amalgamation and mixing of whales throughout the ocean basin. In the South Pacific song similarity also decreased as distance increased, but it was noted that, at times, adjacent populations could be connected28.A key objective of this study was to examine the relationship between the degree of song similarity and degree of association of whales − using geographic distance apart as a measure of association. The further whales are apart, the less likely they would associate and the greater the song difference. Many of the results were consistent with this model, including trends to fewer shared phrases and weaker correlation values with increasing distance, and with exclusive phrases found only in populations furthest distant from each other. Earlier multi-location, same ocean, song studies indicated similar relationshipsThis study suggests that in the North Pacific song does indeed reflect humpback whale associations but these  associations are not limited by, or a function of, geography. Other, variable environmental, ecological or social factors ultimately determine the distribution of humpback whales and the clumping or splitting of subpopulations, and, in turn, affect song consistency or variety across the ocean at any given time. This raises the possibility that the song dynamic of divergence and convergence is a reflection of the group dynamics of humpback whales reacting to large-scale ecological (e.g. prey) or environmental (e.g. sea temperature) variability in the North Pacific ocean.28. However, apparent differences in song dynamics between the hemispheres complicate a comparison. These include, in the South, rapid changes in the entire song, and several entirely different songs present at any one time across the region − neither have been reported in the North16. However, a study of South Pacific humpback whale population structure based on song proposed a metapopulation structure28, a broad concept where spatially separated populations interact at some level, one that may also be applicable to the North Pacific21. The possibility of a similar population structure but differing song dynamics between hemispheres is intriguing and warrants further investigation.Extensive humpback whale song comparisons have been undertaken in the southeastern South Pacific including eastern Australia, New Caledonia, Tonga, Samoa, Cook Islands and French Polynesia42. However, to date the import of this mixing has often been minimized, as separate North Pacific ‘stocks’ were designated40.This study, along with previous song comparison studies, indicates that populations of humpback whales throughout the North Pacific mix on an ongoing basis, and have done so for as long as we have studied them. Photo-identification matches and satellite tagging clearly indicate the potential for ocean-wide mixing, with individuals on one feeding ground migrating to different winter assembly locations; individuals changing their winter destination year to year - and even one record of multiple crossings of the Pacific from Asia to the North American coast43. The NMFS decision portrays the different North Pacific populations being independent, biologically discrete and distinct (hence managed separately), whereas songs suggest they may actually be integrated, interactive and temporary – making, among other things, the different status designations questionable.The recent NOAA/NMFS (2016) regulatory action  divided the North Pacific humpback whale population into four ‘Distinct Population Segments’ (DPSs) based on winter assemblies, and gave them different status: Central American – Endangered; Mexico – Threatened; Hawaii – no protection warranted; and Western North Pacific – Endangered23. This study described the fluidity of song composition within and between the North Pacific groups, presumably the result of constantly changing associations, of, at least, males, that include, perhaps necessitate, real-time acoustic definition. It appears the song provides an immediate social identity to transitory groupings of whales. Whether this is a clue to its function is not known. What whales might do with such information is not known.Do these large scale, ocean-wide, population-level comparisons provide insight into the biological function of the song? To date, all studies agreed that shared song composition means singers have associated, at least acoustically, in some recent time frameThe datasets generated during and/or analysed during the current study are available from the corresponding author on reasonable request.Convergence and divergence of songs suggest ongoing, but annually variable, mixing of humpback whale populations throughout the North Paciific


Cardiac involvement is common and is the leading cause of mortality in Fabry disease (FD). We explored the association between cardiovascular magnetic resonance (CMR) myocardial strain, T1 mapping, late gadolinium enhancement (LGE) and left ventricular hypertrophy (LVH) in patients with FD.In this prospective study, 38 FD patients  and 8 healthy controls  underwent 3 T CMR including cine balanced steady-state free precession (bSSFP), LGE and modified Look-Locker Inversion recovery (MOLLI) T1 mapping. Global longitudinal (GLS) and circumferential (GCS) strain and base-to-apex longitudinal strain (LS) and circumferential strain (CS) gradients were derived from cine bSSFP images using feature tracking analysis.p = 0.45), GCS  or base-to-apex LS gradient . FD patients had significantly lower base-to-apex CS gradient  and native T1 . Base-to-apex CS gradient differentiated FD LVH- LGE- patients from healthy controls , even after controlling for native T1 . In a nested logistic regression model with native T1, model fit was significantly improved by the addition of base-to-apex CS gradient (χ2(df = 1) = 11.04, p < 0.001). Intra- and inter-observer agreement were moderate to good for myocardial strain parameters: GLS , GCS , and base-to-apex CS gradient .Among FD patients, 8 had LVH  and 17 had LGE . Nineteen FD patients (50%) had neither LVH nor LGE (FD LVH- LGE-). None of the healthy controls had LVH or LGE. FD patients and healthy controls did not differ significantly with respect to GLS (− 15.3 ± 3.5% vs. − 16.3 ± 1.5%, CMR reproducibly identifies myocardial strain abnormalities in FD. Loss of base-to-apex CS gradient may be an early marker of cardiac involvement in FD, with independent and incremental value beyond native T1. Fabry disease (FD) is an X-linked disorder characterized by progressive accumulation of lysosomal sphingolipids in multiple organs . CardiacCardiovascular magnetic resonance (CMR) is routinely used in the evaluation of patients with FD, including assessment of left ventricular hypertrophy (LVH), late gadolinium enhancement (LGE) and native T1 mapping –7. CMR fMyocardial strain abnormalities assessed by echocardiography have been described in FD, including reductions in longitudinal (LS) and circumferential strain (CS) and loss of base-to-apex CS gradient –13. HoweWe sought to explore the association between CMR feature tracking derived myocardial strain, LVH, LGE and T1 mapping in FD patients. We hypothesize that CMR identified loss of base-to-apex CS gradient may be an early marker of cardiac involvement in FD.From June 2016 to May 2018, consecutive FD patients undergoing 3 T CMR at our institution were prospectively enrolled. The study was approved by the institutional research ethics board and written informed consent was obtained from all subjects. Inclusion criteria for patients included age ≥ 18 years and confirmed diagnosis of FD. Exclusion criteria included prior myocardial infarction or known coronary artery disease and contraindications to CMR. A reference healthy control group was also imaged, defined as volunteers without past medical history of cardiovascular disease. The final study population consisted of thirty-eight gene-positive FD patients  and eight healthy controls .All CMR studies were performed using a 3 T scanner . Multi-planar retrospectively gated cine balanced steady-state free precession (bSSFP) images were obtained including multiple long-axis planes and a stack of short-axis slices with coverage from cardiac base to apex (8 mm slice thickness and 2 mm inter-slice gap). Multi-planar LGE imaging was performed approximately 15 min after administration of 0.15 mmol/kg body weight of gadobutrol  employing a phase sensitive inversion recovery gradient-recalled echo sequence (8 mm slice thickness and 2 mm inter-slice gap) at matching slice positions. Native and 12–15 min post-contrast mid-ventricular short-axis T1 maps were acquired using a bSSFP readout modified Look-Locker inversion recovery (MOLLI) technique with inline motion correction and map creation (native (5(3)3) and post-contrast (4(1)3(1)2) inversion groupings, 8 mm slice thickness) .2 in males and > 81 g/m2 in females [CMR analysis was performed by a fellowship-trained radiologist  blinded to all identifying information using commercially available software . LV endocardial and epicardial borders were contoured on the stack of short-axis bSSFP images to assess for left ventricular (LV) volumes, LV ejection fraction (LVEF), and mass, and on short axis LGE images to assess for the extent of LGE. LVH was defined as LV mass indexed to body surface area (BSA) > 85 g/m females . All LGE females . For fea females . T1 valu females . Myocard females , 21.Fig.To assess intra-observer agreement for strain analysis, a random subset of 15 studies were re-analyzed by the same reader following a minimum 2-week interval after the first analysis, blinded to the results of the initial assessment and all identifying data. To assess inter-observer agreement, the same subset of studies was analyzed by a second experienced fellowship-trained reader , blinded to all identifying information including the results of the initial assessment.p-value of < 0.05 was considered statistically significant. Continuous variables were described using mean and standard deviation and categorical variables using numbers and percentage. All continuous data were tested for normal distribution using the Shapiro-Wilk test. Comparisons between groups were made by independent samples t-test for continuous variables with normal distribution, Wilcoxon rank-sum test for continuous variables with non-normal distribution, and Fisher’s exact test for categorical variables. Correlation between continuous variables was assessed using Spearman correlation. Univariable logistic regression was used to evaluate the ability of native T1, ECV, GLS, GCS, base-to-apex LS gradient and base-to-apex CS gradient to differentiate FD patients without LVH or LGE from healthy controls. To evaluate whether sex is an effect modifier, interaction terms for sex and base-to-apex CS gradient and for sex and native T1 were included in respective logistic regression models along with sex as a main effect and tested for significance. A bivariable logistic regression model was fitted with base-to-apex CS gradient and native T1. For assessment of incremental diagnostic value, the likelihood ratio test was used to compare nested models with native T1 versus one with base-to-apex CS gradient added. Intra- and inter-observer agreement were assessed using individual intra-class correlation coefficients with one-way random effects models and two-way random effects models, respectively.Statistical analysis was performed using STATA v14.1 . A two-tailed Baseline clinical information is summarized in Table p < 0.001), even when the comparison was restricted to the LVH- LGE- subgroup , FD LVH+ subgroup , and FD LGE+ subgroup  , even when the comparison was restricted to the FD LVH- LGE- subgroup , FD LVH+ subgroup , and FD LGE + subgroup  .Native T1 values were significantly lower in FD patients compared to controls , even when the comparison was restricted to the FD LVH- LGE- subgroup   and FD LGE + subgroup  when compared to controls. Among patients with FD, GLS correlated positively with LV mass indexed to BSA  and quantitative LGE , but did not correlate significantly with native T1  or ECV , Table p = 0.09).There was no significant difference in GLS between FD patients and controls , even when the comparison was restricted to the FD LVH- LGE- subgroup (− 20.2 ± 1.8% p = 0.52) and the FD LGE+ subgroup   , but did not correlate significantly with quantitative LGE , native T1 , or ECV . Among FD patients, GCS was significantly lower in males compared to females .There was no significant difference in GCS between FD patients and controls , even when the comparison was restricted to the FD LVH- LGE- subgroup , FD LVH+ subgroup , and FD LGE+ subgroup  , quantitative LGE , native T1  or ECV . Among FD patients, there was no significant difference in base-to-apex LS gradient between males and females .There was no significant difference in base-to-apex LS gradient between FD patients and controls , even when the comparison was restricted to the LVH- LGE- subgroup , FD LVH+ subgroup , and FD LGE+ subgroup  , quantitative LGE , native T1  or ECV . Among FD patients, there was no significant difference in base-to-apex CS gradient between males and females .Base-to-apex CS gradient was significantly lower in FD patients compared to controls  and native T1  were significant in differentiating FD LVH- LGE- patients from healthy controls in univariable models, Table p = 0.41) or native T1  and diagnosis of FD. Base-to-apex CS gradient remained significant in a bivariable logistic regression model after adjusting for native T1 . In this bivariable model, native T1 approached but did not reach statistical significance . In a nested logistic regression model with native T1, model fit was significantly improved by the addition of base-to-apex CS gradient (χ2(df = 1) = 11.04, p < 0.001).Base-to-apex CS gradient .Among patients with FD, 13 (34%) were treated with enzyme replacement therapy. There was no significant difference in native T1, ECV, GLS, GCS, base-to-apex LS gradient or base-to-apex CS gradient between FD patients treated with enzyme replacement therapy and those that were not on therapy , GCS , and base-to-apex CS gradient .The results of this study demonstrate that base-to-apex CS gradient discriminates between FD patients without hypertrophy or LGE and healthy controls independent of native T1, suggesting that loss of base-to-apex CS gradient may be an early marker of cardiac involvement in FD.A few prior studies have evaluated global strain abnormalities using echocardiography in patients with FD, demonstrating minor reductions in GLS and GCS , 11. GruTo our knowledge, only a few prior studies have reported CMR strain results in patients with FD, and none have included assessment of base-to-apex CS gradient. Cheng-Baron et al. assessed myocardial strain in FD using an alternative method, global fractional shortening, and reported that patients with FD had significant differences in strain parameters compared to healthy controls . Rutz etCS and LS normally increase from LV base to apex, which could be due to differences in wall thickness, regional myocardial architecture and local stress , 25. TheOther patterns of abnormal regional myocardial strain have been described in other cardiomyopathies. For example, a pronounced base-to-apex LS gradient with preserved apical longitudinal strain has been shown to differentiate cardiac amyloid from other causes of LVH including FD , 29. We Early detection of cardiac involvement in FD is critical given the availability of disease specific treatment with intravenous infusion of the deficient enzyme or oral pharmacologic chaperone therapy. Recent studies indicate that low native T1 may be an early biomarker of cardiac involvement in FD, even before the development of LVH , 30, 31.Normal myocardial strain values have been shown to vary between studies depending on the imaging acquisition technique, analysis method and post-processing vendor. Absolute GLS and GCS values for healthy controls in our study are slightly lower compared to prior studies, potentially related to the post-processing vendor used , 33. AbsThere are several limitations to our study. FD is a relatively rare disease, thus limiting the number of subjects included. Adjustment for covariates in logistic regression models is limited by the number of subjects. CMR imaging was only performed at 3 T and all analysis was performed using a single post-processing vendor, and therefore results may not be generalizable to different field strengths or software analysis. Given the small number of subjects, we were not able to adjust our analysis for the duration of therapy or underlying disease severity. Future studies including larger numbers of subjects should be performed to investigate whether loss of base-to-apex CS gradient is specific for cardiac involvement in FD, to evaluate the effect of treatment on base-to-apex CS gradient as an imaging end-point, and to assess the prognostic significance of this finding.CMR reproducibly identifies myocardial strain abnormalities in FD. Loss of base-to-apex CS gradient may be an early marker of cardiac involvement in FD, with independent and incremental value beyond native T1.


The effect of sodium glucose cotransporter type 2 (SGLT2) inhibitor on left ventricular (LV) longitudinal myocardial function in type 2 diabetes mellitus (T2DM) patients with heart failure (HF) has remained unclear.We analyzed data from our previous prospective multicenter study, in which we investigated the effect of the SGLT2 inhibitor dapagliflozin on LV diastolic functional parameters of T2DM patients with stable HF at five institutions in Japan. Echocardiography was performed at baseline and 6 months after administration of dapagliflozin. LV diastolic function was defined as the ratio of mitral inflow E to mitral e′ annular velocities (E/e′). LV longitudinal myocardial function was assessed as global longitudinal strain (GLS), which in turn was determined as the averaged peak longitudinal strain from standard LV apical views.E/e′ significantly decreased from 9.3 to 8.5 cm/s 6 months after administration of dapagliflozin (p = 0.020) as previously described, while GLS showed significant improvement from 15.5 ± 3.5% to 16.9 ± 4.1% (p < 0.01) 6 months after administration of dapagliflozin. Furthermore, improvement of GLS in HF with preserved ejection fraction patients was more significant from 17.0 ± 1.9% to 18.7 ± 2.0% (p < 0.001), compared to that in HF with mid-range ejection fraction and HF with reduced ejection fraction patients from 14.4 ± 2.4% to 15.5 ± 1.8% (p = 0.06) and from 8.1 ± 1.5% to 7.8 ± 2.1% (p = 0.44), respectively. It was noteworthy that multiple regression analysis showed that the change in GLS after administration of dapagliflozin was the only independent determinant parameters for the change in E/e′ after administration of dapagliflozin.Dapagliflozin was found to be associated with improvement of LV longitudinal myocardial function, which led to further improvement of LV diastolic function of T2DM patients with stable HF. GLS-guided management may thus lead to improved management of T2DM patients with stable HF. Type 2 diabetes mellitus (T2DM) has come to be considered an independent predictor of mortality, and also a contributor to the development of heart failure (HF) in patients with reduced ejection fraction (HFrEF) and with preserved ejection fraction (HFpEF), as well as cardiovascular disease , 2. Diab2; 6. hypotension < 90/50 mmHg; 7. malignancy; 8. poor nutritional status; and 9. atrial fibrillation. According to the current guideline [The details of our prospective multicenter study have been described previously . Brieflyuideline , patientStable HF patients who had been taking at least one antidiabetic drug other than SGLT2 inhibitors and who had consented to their participation in this study, started the administration of dapagliflozin at 5 mg/day. Other drugs were not changed after the start of administration of dapagliflozin. The physical examinations and blood tests were performed at baseline, 3 months, and 6 months after administration of dapagliflozin, while echocardiography was performed at baseline and 6 months after administration of the SGLT2 inhibitor. Only if a patient’s HbA1c had failed to improve by 3 months after administration of dapagliflozin, the dose was raised from 5 to 10 mg/day.All patients underwent a resting standard echocardiographic examination using commercially available echocardiography systems . Digital routine grayscale two-dimensional cine loops from three consecutive heart beats were obtained at end-expiratory apnea from standard parasternal and apical views. Sector width was optimized to allow for complete myocardial visualization while maximizing the frame rate. Standard echocardiographic measurements were obtained in accordance with the current guidelines of the American Society of Echocardiography/European Association of Cardiovascular Imaging .Speckle-tracking strain analysis was performed for each patient with the aid of a single dedicated software to evaluate LV longitudinal function, which was assessed in terms of GLS . Briefly, apical 4-, 2- and long-axis views with the Digital Imaging and Communications in Medicine (DICOM) formatted file images were uploaded onto a personal computer for subsequent off-line GLS analysis Fig. . LongituContinuous variables were expressed as mean values and standard deviation for normally distributed data, and as the median and interquartile range for non-normally distributed data. Categorical variables were expressed as frequencies and percentages. Paired t tests or Wilcoxon signed-rank test were used for group comparison between baseline and 6 months after the start of administration of dapagliflozin. Independent associations of changes in E/e′ between baseline and 6 months after the start of administration of dapagliflozin with clinical and echocardiographic parameters were evaluated by means of multiple regression analysis. The intraclass correlation coefficient was used to determine inter- and intra-observer reproducibilities for GLS from 20 randomly selected patients using an identical cine-loop for each view. For all steps, p < 0.05 was considered statistically significant. All analyses were performed with commercially available software .The baseline clinical and echocardiographic characteristics of the 53 T2DM patients are summarized in Table All clinical and echocardiographic characteristics including LV diastolic function of the 53 T2DM patients at baseline and 6 months after administration of dapagliflozin are summarized in Table Furthermore, improvement of GLS 6 months after administration of dapagliflozin in HFpEF patients was more significant from 17.0 ± 1.9% to 18.7 ± 2.0% (p < 0.001), compared to that in HFmrEF and HFrEF patients from 14.4 ± 2.4% to 15.5 ± 1.8% (p = 0.06) and from 8.1 ± 1.5% to 7.8 ± 2.1% (p = 0.44), respectively Fig. .Fig. 3BaTable The intraclass correlation coefficient for inter-observer reproducibility of GLS was 0.954 , and the intraclass correlation coefficient for intra-observer reproducibility of GLS was 0.986 .The findings of our study indicate that LV longitudinal myocardial function, assessed in terms of GLS for T2DM patients with stable HF, had significantly improved 6 months after administration of dapagliflozin. In addition, improvement of GLS for HFpEF patients was superior to that for non-HFpEF patients. Importantly, improvements of GLS were strongly associated with those in E/e′ 6 months after administration of dapagliflozin.The presence of T2DM has come to be considered an independent predictor of mortality, and also a contributor to the development of HF in patients with HFrEF and HFpEF , 2. It iOn the other hand, LV longitudinal myocardial dysfunction has been identified even in T2DM patients with preserved LVEF but without overt coronary artery disease and overt HF –10, so tLeung et al. showed that improvements in glycemic control by antidiabetic drugs including insulin (not including SGLT2 inhibitors) led to improvements in GLS as well as LV diastolic function in asymptomatic T2DM patients with preserved LVEF during 12-month follow-up . MoreoveDECLARE-TIMI 58 was a large trial that assessed cardiovascular outcomes for 17,160 patients who were treated with the SGLT2 inhibitor dapagliflozin and followed for a median of 4.2 years . Main fiIt is well known that SGLT2 inhibitor is associated with lower blood pressure and weight loss as well as a reduction in HbA1c levels, changes which in turn have a significant impact on LV function. Moreover, canagliflozin, an SGLT2 inhibitor, reduced the risk of kidney failure as well as cardiovascular events compared to the placebo group for T2DM patients with albuminuric chronic kidney disease, followed up for a median of 2.62 years . TherefoAlthough LV diastolic function also plays an important role for patients with HFrEF as well as HFpEF in the development of cardiovascular events and outcomes, LV longitudinal myocardial function assessed in terms of GLS has been reported to be a sensitive marker of early subtle abnormalities of LV myocardial performance, helpful for the prediction of outcomes for various cardiac diseases, and superior to conventional echocardiographic indices –33. ThusThis study comprised a small number of patients and did not use a placebo-controlled group, so that future prospective studies with larger patient populations including placebo-controlled groups will be needed to validate our findings. In fact, EMPA-HEART trial of a prospective study is currently in progress . In thisDapagliflozin was shown to be associated with improvement of LV longitudinal myocardial function, leading to further improvement of LV diastolic function for T2DM patients with stable HF. GLS-guided management may thus have potential for better management of T2DM patients with stable HF.


The management of heart failure has changed significantly over the last 30 years, leading to improvements in the quality of life and outcomes, at least for patients with a substantially reduced left ventricular ejection fraction (HFrEF). This has been made possible by the identification of various pathways leading to the development and progression of heart failure, which have been successfully targeted with effective therapies. Meanwhile, many other potential targets of treatment have been identified, and the list is constantly expanding. In this review, we summarise planned and ongoing trials exploring the potential benefit, or harm, of old and new pharmacological interventions that might offer further improvements in treatment for those with HFrEF and extend success to the treatment of patients with heart failure with preserved left ventricular ejection fraction (HFpEF) and other heart failure phenotypes.The online version of this article (10.1007/s10741-019-09829-7) contains supplementary material, which is available to authorized users. Heart failure and its management have changed dramatically over the last 30 years. In the 1980s, patients were included in clinical trials of heart failure based purely on the clinical opinion of the investigator with no objective criteria to confirm the diagnosis. The patients were younger and had fewer comorbidities but a broad range of left ventricular ejection fraction (LVEF) compared with contemporary trials; quality of life was often poor and mortality rate high. Fluid retention, causing peripheral oedema and breathlessness, was the main therapeutic target. Digoxin and diuretics were the only available medical treatments, sometimes accompanied with bed rest and fluid restriction.Subsequently, objective criteria such as LVEF and, more recently, natriuretic peptides were required to select patients for trials. Initially, trials targeted vasoconstriction, using nitrates and hydralazine , and patDespite these successes, the ‘war’ on heart failure is far from won. For patients hospitalised with worsening heart failure aged less than 75 years, mortality at 1 year may be as high as 20% and up to 40% in those aged > 85 years . For patMore appropriate use of investigations and less complex diagnostic algorithms are likely to reveal that there are many undiagnosed cases of heart failure in the community, particularly with preserved left ventricular (LV) ejection fraction (HFpEF) , a condiThe age-adjusted incidence of heart failure may be fairly stable but the total number of patients who will develop heart failure will rise substantially in the next few decades as the proportion of people aged > 60 years increases . NowadayEnormous amounts of routinely collected personal health records, biochemical and imaging data are now available for novel analytical approaches such as machine-learning and artificial intelligence that will identify novel pathways leading to heart failure and redefine its epidemiology in the next decade Fig. . The defCurrently, there are many ongoing trials exploring the potential for benefit, or harm, of old and new treatments that might improve the management of HF: summarising novel pharmacological interventions is the purpose of this review; space precludes an in-depth review of devices  or biological interventions (other than influenza vaccination) although key trials are shown in the Table n = 881) during the in-hospital recovery phase after an acute decompensation was as safe as initiating enalapril, but led to a greater, and earlier (within 1 week), reduction in plasma concentrations of NT-proBNP, which was sustained until the end of 8 weeks follow-up [n = 118), patients with HF, an LVEF < 50% and functional mitral regurgitation (MR) who were randomised to sacubitril/valsartan had a greater reduction in the effective regurgitant orifice area (EROA) compared with valsartan alone at 12 months follow-up [One of the key therapeutic successes for heart failure has been the inhibition of neuro-endocrine pathways with ACE-Is, ARBs, MRAs and beta-blockers. Recently, a new class of agents, angiotensin receptor neprilysin inhibitors (ARNI), has proved superior to ACE-Is for the treatment of HFrEF . Neprilyollow-up . A reducollow-up . Howeverollow-up . In the ollow-up . Other tThe Prospective Comparison of ARNI with ARB Global Outcomes in HF With Preserved Ejection Fraction  is a randomised, double-blind, event-driven trial comparing the efficacy and safety of valsartan vs sacubitril/valsartan in patients with HFpEF that has enrolled 4822 patients  pg/mL, > 2/3 in sinus rhythm) . The resneprilysin could interfere with breakdown of beta amyloid (βA) peptides, which might accumulate in the brain and contribute to the development of Alzheimer’s disease. The PERSPECTIVE trial (NCT02884206) is currently recruiting ~ 500 patients with HF and LVEF > 40%, to investigate whether chronic administration of sacubitril/valsartan for 3 years leads to a decline in cognitive function when compared with valsartan alone.Concerns exist that the inhibition of Currently, based on the evidence provided by clinical trials, guidelines recommend that ACEi, ARB and MRA should not be initiated if serum potassium is > 5.0 mmol/L (5.2 mmol/L for ARNI) and that doses should be reduced or treatment stopped if serum potassium is > 5.5 mmol/L. Accordingly, many patients with HFrEF do not receive guideline-recommended doses of these agents , 17, 31.Patiromer and sodium zirconium cyclosilicate are novel oral treatments that bind potassium in the gastrointestinal (GI) tract and rapidly normalise serum potassium concentrations. Whether their use will allow doctors to prescribe and patients to achieve guideline-recommended doses of RAASi more often and whether this will improve outcomes are now being investigated. Results of substantial trials are not expected before 2021.Nitric oxide (NO) activates soluble guanylate cyclase (sGC), causing an elevation of intracellular cyclic guanosine monophosphate (cGMP) in vascular and non-vascular tissues, such as the myocardium and kidney. In heart failure, production of NO is reduced and its degradation is increased, leading to an increase in systemic and pulmonary arteriolar and venous tone, thereby increasing the after-load and pre-load on the failing myocardium . VericigNitroxyl is a second-generation donor of nitric oxide that causes vasodilatation and may have inotropic effects, which are only partially mediated by an increase in cGMP . A phasen ~ 8,000) phase III trial of patients with chronic HFrEF  is nearing completion of enrolment and should report in 2021 .Omecamtiv mecarbil (OM) is a cardiac myosin activator that alters the kinetics of actin/myosin cross-bridges, prolonging the duration of the systole and, thus, stroke volume, without increasing ATP consumption . Phase ILevosimendan, a vasodilator and calcium sensitiser, has been used to treat refractory HF in many countries despite two large neutral trials conducted in patients with acute HF and a large trial of an oral formulation in patients with chronic severe HF that showed reductions in NT-proBNP and an improvement in QoL but did not otherwise improve outcome , 41. RecNeuregulin-1 proteins are important for the development and function of cardiac myocytes. Small phase II studies reported that recombinant human neuregulin-1 improved haemodynamics and promoted reverse LV remodelling in patients with HFrEF , 44. A pDigoxin may be the oldest medicine still prescribed for heart failure, but controversies persist about its benefits. In the DIG trial, conducted before many current HF treatments were available, digoxin did not reduce mortality compared to placebo, although it did reduce HF hospitalisations by 28%. A retrospective analysis suggested that patients with serum concentrations of digoxin of 0.5–0.9 ng/mL were more likely to benefit , 46. A pCongestion is an important cause of the symptoms and signs of HF, leads to adverse atrial and ventricular remodelling, arrhythmias and worsening renal function and is associated with poor outcomes , 48. ConLoop diuretics are the most potent diuretic agents, and furosemide is the most widely used in patients with HF. However, other loop diuretics, such as bumetanide and torasemide, are either better absorbed or delivered more reliably to the renal tubule. Meta-analysis of small randomised trials and observational studies suggests that torasemide might be superior to furosemide, but no substantial randomised trial has yet compared these two agents –54. TRANOther options for treating resistant congestion in patients HF exist, such as combining different classes of diuretics, but their safety and efficacy have been rarely tested in clinical trials . Most ofAlthough not everyone would agree that it is the principal mechanism of action of sodium glucose co-transporter 2 inhibitors (SGLT2i), there is little doubt that diuresis contributes to their effects in HF. SGLT2i reduce glucose reabsorption in the proximal nephron, increasing delivery of glucose and sodium to the distal nephron and inducing an osmotic diuresis. Whether SGLT2i have additional metabolic effects on the heart and kidney by inhibiting carbonic anhydrase or increasing the availability of ketones as a metabolic substrate for the myocardium is uncertain . Empaglin = 34) or other (n = 4) deaths and does not prove long-term safety [Up to 50% of patients with HF have iron deficiency (ID), with or without anaemia. ID is associated with adverse outcomes, even in the absence of anaemia, and is a potential target of treatment . Oral irm safety . Four suHeart failure may be accompanied by high plasma copper concentrations but myocardial copper depletion. There is evidence from both animal models and a limited amount of human data that copper chelation may be beneficial . HoweverCo-enzyme Q10 is an essential component of the mitochondrial electron transport chain and both co-enzyme Q10 and selenium have an important role in many metabolic processes. Lower plasma concentrations of Q10 and selenium have been associated with adverse outcomes in heart failure –69. Two n ~ 300) of HFpEF and PHT. However, trials in patients with HFrEF were stopped for harm. The safety, and effect on NT-proBNP levels of macitentan, an antagonist/blocker of endothelin receptors, will be also studied in 300 patients with HFpEF complicated by PHT or right ventricular dysfunction .Pulmonary hypertension (PHT) is common, especially in patients with advanced heart failure, due to a combination of left atrial hypertension, pulmonary arteriolar hypertrophy and pulmonary vasoconstriction. Small trials have shown that sildenafil, a selective inhibitor of type 5 phosphodiesterase, might improve haemodynamics and exercise performance in patients with HFrEF and PHT; other trials should report soon . In HFpEAccumulation of wild-type or variant transthyretin amyloid occurs when fibrils become unstable and misfold. Recent reports suggest that 15–20% of patients with HFpEF may have TTR amyloidosis. These patients have a poor outcome and may not respond to conventional treatments . A recenInfluenza might be an important precipitant of HF hospitalisations . A recenOver the last 30 years, various pathways leading to the development and progression of heart failure have been identified and successfully targeted with effective therapies. This has improved the quality of life and survival for millions of individuals with HFrEF, globally. Hopefully, new treatments will offer further improvements and extend these successes to the treatment of HFpEF and other specific causes and phenotypes of HF. New concepts of how HF should be defined combined with new analytical approaches using large data-sets will re-shape its epidemiology and offer new therapeutic targets. However, old age rather than cardiac dysfunction may be the next great barrier to overcome.ESM 1(DOCX 23 kb)


Gross tumour volumes (GTV) of tumour (T), lymph nodes (LN) and hypoxic subvolumes  and complementary non-hypoxic subvolumes (nonHSV) were generated. Mean values for T2* and SUVmean FDG were determined.p = 0.051), whereas FDG SUVmean (12 ± 6) was significantly higher for HSV-T (12 ± 6) than for nonHSV-T  and higher for HSV-LN (10 ± 4) than for nonHSV-LN . Correlation between FMISO PET and FDG PET was higher than between FMSIO PET and T2* (R2 for GTV-T (FMISO/FDG) = 0.81, R2 for GTV-T (FMISO/T2*) = 0.32).During RCT, marked reduction of tumour hypoxia on FMISO-PET was observed , while mean T2* did not change significantly. At baseline, mean T2* values within HSV-T (15 ± 5 ms) were smaller compared to nonHSV-T  contains supplementary material, which is available to authorized users. All patients received an injection of 243–332 MBq (6.6–9.0 mCi) 18F-MISO and of 303–471 MBq (8.2–12.7 mCi) 18F-FDG, respectively. In case of 18F-FDG whole body PET/CT scans were performed 1 h p.i.  with contrast-enhanced diagnostic CT  and 2 mm slice thickness from the base of the skull to the proximal femur . A subsequent low-dose PET/CT scan was performed in one bed position (10 min) covering the head and neck region. Static 18F-MISO PET/CT was executed in one bed position (20 min) covering the head and neck region 160 min p.i., following our previous study [[3, matrix size: 2562, 12 echoes, monopolar readout gradients, echo times TE = 4.83–33.0 ms, echo spacing ΔTE = 2.55 ms, repetition time TR = 400 ms, flip angle α = 60°, readout bandwidth = 815 Hz/pixel, total acquisition time = 1:42 min:s.As part of a multi-parameter MR imaging protocol consisting of T1w-MRI, T2w-MRI, dynamic contrast enhanced (DCE-MRI) perfusion measurements and diffusion weighted measurements (DWI-MRI), and multi-echo fast spoiled gradient echo (FLASH) data were acquired on a clinical 3 Tesla MRI system . For this, patients were positioned on the MR system table in the MR-compatible immobilization mask, an anterior 4-element flexible radiofrequency receiver coil (Flex Loop Large) was wrapped around the head-and-neck region, and data were acquired in combination with the posterior spine coil elements within the patient table to maximize the local signal-to-noise ratio at the tumour. The multi-echo acquisition for T2* measurements was acquired prior to the DCE measurements, and imaging slices were defined in transverse orientation. The following imaging parameters were used: 22 slices, spatial resolution: 3 (slice thickness) × 1.1 × 1.1 mm0 exp.(−TE/T2*)) fit to the signal. To avoid noise bias, signal intensities in later echoes that were smaller than 5 times the noise level were not used for fitting.From the multi-echo FLASH image series, a T2* map was calculated for each slice position by a pixel-wise mono-exponential (S(TE) = SFor all image acquisitions  patients were immobilized identical to the radiation position with individually casted head and neck masks.2 was calculated using linear regression analysis (SigmaPlot). For week 0, correlations between FMISO uptake, FDG uptake and T2* were analysed by correlating SUVmax tumour/SUVmean muscle for FMISO and FDG with each other and with mean T2* signal: within GTV-T (respectively within GTV-LN), R2 (FMISO to T2*) was calculated for FMISO SUVmax GTV-T/SUVmean NT to T2* mean GTV-T and R2 (FMISO to FDG) was calculated for FMISO SUVmax GTV-T/SUVmean NT to FDG SUVmax GTV-T/SUVmean NT. For weeks 2 and 5, correlations between FMISO uptake and T2* were analysed.Image data were transferred to iplan net planning software (BrainLAB) and co-registered. The GTV for primary tumour (GTV-T) and pathological lymph nodes (GTV-LN) for weeks 0, 2, and 5 were contoured within MRI images based on contrast-enhanced T1w-MRI Gd (Gadolinium) and T2 sequences as consensus volumes between a board certified radiologist and radiation oncologist. At week 0, the FDG-PET additional information was considered for GTV contouring. A representative normal tissue volume (NT) was contoured as a sphere within the contralateral sternocleidomastoid muscle. Hypoxic tumour subvolumes (HSV-T), hypoxic lymph node subvolumes (HSV-LN), and complementary non-hypoxic tumour subvolumes and non-hypoxic lymph node subvolumes  were generated for a threshold level of 1.4 times the FMISO SUVmean within the NT. Volumes were contoured for all time points  individually. Average values and standard deviation for T2* values and FDG SUVmean were obtained within the volumes NT, GTV-T, GTV-LN, and hypoxic subvolumes HSV-T, HSV-LN and complementary non-hypoxic subvolumes nonHSV-T and nonHSV-LN, respectively . GTV-LN showed significantly higher mean T2* at week 2 compared to NT and GTV-T: 27.6 ms for GTV-LN compared to 21.0 ms for NT (p = 0.021) and 19.1 ms for GTV-T (p = 0.009). Mean T2* showed no significant change over time for GTV-T while for GTV-LN a slight decrease week 2 to 5 was seen (p = 0.049). GTV and HSV contours in MRI T2* as well as the range of T2* values are visualized in Additional file Mean values for T2* were obtained within designated volumes for each patient , see Fig. p = 0.895, p = 0.545, Additional file p = 0.026 and p = 0.011). By definition, FMISO uptake was higher within hypoxic tumour subvolumes as compared to non-hypoxic tumour subvolumes. See Fig. p = 0.53 and p = 0.94).Hypoxic and complementary non-hypoxic tumour and lymph node subvolumes derived from FMISO-PET were compared for T2* signal and FDG SUVmean. HSV-T showed smaller mean T2* values compared to nonHSV-T for all time points, reaching borderline significance level at week 0 , and 0.32 between FMISO and T2* (p = 0.1157). For GTV-LN, the comparison between FMISO and FDG yielded an R2 of 0.30 (p = 0.2057), and an R2 of 0.51 (p = 0.0459) between FMISO and T2*. At weeks 2 and 5, R2 between FMISO and T2* was 0.37 (p = 0.1073) and 0.12 (p = 0.3663) for GTV-T, and 0.04 (p = 0.6334) and 0.01 (p = 0.8089) for GTV-LN. Correlation plots for GTV-T at baseline are shown in Fig. For GTV-T at week 0, the linear regression coefficient R p = 0.004, and 0.T2* measurements are being considered a novel non-invasive MRI imaging marker for tumour oxygenation –34 whereThe more than 50% reduction of GTV-T and GTV-LN up to week 5 and the marked reduction of tumour hypoxia on FMISO-PET (i.e. HSV) in this study are in line with previous findings , 7, 8. SIt is of note that for GTV-LN higher T2* values were found than for GTV-T for all time points (reaching significance level at week 2). In line with this finding, Panek et al.  also desp = 0.051). Our findings on T2* values within HSV over time were opposed for GTV-T and GTV-LN: within hypoxic tumour volumes, T2* steadily increased from week 0 to 5, supportive for improved tumour oxygenation over time, whereas within hypoxic lymph node subvolumes a slight decrease was seen (none of these changes were significant).The comparison between FMISO-PET derived hypoxic tumour subvolumes to complementary non-hypoxic tumour subvolumes showed smaller T2* values for HSV as compared to non-HSV for all time points. This might indicate a correlation between oxygenation status and T2* before therapy. Statistical significance was not reached, however a borderline significance level (2 = 0.81) whereas only a weak correlation (R2 = 0.32) was found between FMISO uptake and mean T2*. Interestingly, for lymph nodes the correlation between FMISO and T2* was moderate (R2 = 0.51) while the correlation between FMISO and FDG was weak (R2 = 0.30).FDG-PET was conducted only once (week 0) and not at later time points for patient convenience. FDG uptake within hypoxic subvolumes was significantly higher than within complementary non-hypoxic subvolumes for both tumour and lymph nodes. Accordingly, within GTV-T the correlation between FMISO uptake and FDG uptake was strong  were fused by a treatment planning software with validated image registration algorithm. However, image fusion within the head and neck region is more critical than intracranial image fusion due to anatomical and physiological reasons. 2. The hypoxic subvolumes used for analysis of average T2* values were representative at baseline but became very small at later time points. 3. The study evaluates a relatively small number of patients. Including a higher number of patients however would raise an ethical problem due to the burden imposed on patients by frequent imaging sessions and long imaging protocols. In the current study, 11 of 32 patients could not be considered as they were included before availability of the 3 Tesla MRI. For the remaining 21 patients, a high dropout rate was found, as only 10 fulfilled inclusion criteria due to missing image sets.Nevertheless, this prospective trial demonstrated that clinically, T2* may not be suitable to replace FMISO PET as a valuable surrogate imaging marker to monitor tumour oxygenation and hypoxic areas during the course of radiotherapy. Future analyses are planned to further examine the role of T2* imaging in the context of tumour hypoxia.In summary, marked reduction of tumour hypoxia between week 0, 2 and 5 found on FMISO-PET was not accompanied by a significant T2*change within GTVs over time. Our results suggest a relation between tumour oxygenation status and T2* at baseline, but no simple correlation during the course of radiotherapy. Therefore, caution is warranted when using T2* as a substitute for FMISO-PET to monitor tumour hypoxia during RCT in HNSCC patients.Additional file 1:Table S1. Patient characteristics. (DOCX 15 kb)Additional file 2:Figure S1.Volumes analysed. FMISO-PET with volumes used for analysis: GTV-T, GTV-LN, HSV-T, nonHSV-T, HSV-LN, nonHSV-LN. (TIF 216 kb)Additional file 3:Table S2. T2* values within volumes. Mean, median, and STD for T2*mean (ms) measurements for all patients (n = 10). (DOCX 15 kb)Additional file 4:Table S3. Number of lymph nodes within GTV-LN. (DOCX 13 kb)Additional file 5:Figure S2.Individual plots of T2*. Plots of T2*mean for individual patients over time. (TIF 46 kb)Additional file 6:Figure S3.Hypoxic subvolume HSV-LN and GTVs on MRI T2*. MRI T2* (ms) showing GTV-T, GTV-LN (red contours) and HSV-LN (green contour) at week 0. (TIF 1376 kb)


Noninvasive imaging modalities offer the possibility to dynamically evaluate cardiac motion during the cardiac cycle by means of ECG-gated acquisitions. Such motion characterization along with orientation, segmentation preprocessing, and ultimately, phase analysis, can provide quantitative estimates of ventricular mechanical synchrony. Current evidence on the role of mechanical synchrony evaluation is mainly available for echocardiography and gated single-photon emission computed tomography, but less is known about the utilization of gated positron emission tomography (PET). Although data available are sparse, there is indication that mechanical synchrony evaluation can be of diagnostic and prognostic values in patients with known or suspected coronary artery disease-related myocardial ischemia, prediction of response to cardiac resynchronization therapy, and estimation of risk for adverse cardiac events in patients’ heart failure. As such, the evaluation of mechanical ventricular synchrony through phase analysis of gated acquisitions represents a value addition to modern cardiac PET imaging modality, which warrants further research and development in the evaluation of patients with cardiovascular disease.The online version of this article (10.1007/s12350-019-01670-7) contains supplementary material, which is available to authorized users. Beyond their capabilities to characterize myocardial architecture, perfusion, viability, and function, noninvasive imaging modalities offer the added possibility to dynamically evaluate ventricular motion during the cardiac cycle by means of ECG-gated acquisitions.3Currently, evidence on the evaluation of mechanical synchrony is mainly available for echocardiography, equilibrium radionuclide angiocardiographyPET represents a state-of-the-art modality in cardiac imaging that allows the evaluation of quantitative physiological parameters  determined by the selected radiotracer. The intrinsic advantages of PET in comparison to SPECT technology such as higher count rates, more physiological tracers, and increased spatial resolution provide high-quality and quantitative images that boost the diagnostic and prognostic utility at a reasonable radiation burden.Current PET scanners operate with list-mode acquisitions in order to obtain adequate datasets for the reconstruction of dynamic, static, and particularly (ECG-) gated images. The latter considers the ECG signal obtained in parallel to the acquisition and tracks wall thickening and changes in the detected cavity contours throughout the averaged cardiac cycle, typically binned into 8 or 16 frames  function , it is possible that phase analysis may be affected when substantial rhythm or motion disturbances are encountered .14In contrast with SPECT, there is a relative paucity of publications on the feasibility, validation, average parameter values in populations of interest, and clinical utility regarding PET (dys)synchrony imaging, as evidenced in Table 18F-FDG and 82Rb as viability and perfusion radiotracers, respectively. In fact, only one study has evaluated correlates and determinants of synchrony measurements from 13N-ammonia PET perfusion data,15O-water for such evaluation.A large number of published reports on mechanical ventricular synchrony evaluated with PET have utilized A number of variables have been proposed to associate with mechanical dyssynchrony in retrospective studies such as QRS duration , intraventricular conduction delay (as seen in patients with left bundle branch block [LBBB]) and LVEF.A parallel working concept in the field of cardiac PET deals with the relationship between myocardial ischemia and ventricular synchrony.Although SPECT studies have aimed to better characterize the phenomenon,In patients with HF who may ultimately attract criteria for the indication of CRTOnly a handful of studies performed with PET have addressed the potential prognostic value of mechanical synchrony. The results of this very discrete body of evidence are inclined to be in favor of a discernible independent hazard ratio of synchrony measures as predictors of all-cause mortality in patients with ischemic cardiomyopathy,29Table Another factor of interest is the availability of several commercial software packages that offer phase analysis. Overall, phase analysis has been implemented in the Emory Cardiac Toolbox 4DM and QGS software. Variability across packages has recently been addressed by Okuda et al,In summary, ventricular mechanical synchrony as measured by PET imaging may be of value in the evaluation of patients with suspected myocardial ischemia leading to myocardial stunning and in patients with HF with an indication for CRT due to the suspected substrate of mechanical dyssynchrony. At the same time, it is likely that PET synchrony evaluation may hold prognostic values in patients with HF and in patients with CAD, in particular with multivessel disease BW of which and the SD of the phase after exercise are significantly increased. In addition, phase analysis is able to detect the LV mechanical dyssynchrony due to the vasomotion changes associated with occult atherosclerosis in patients with normal coronary angiography findings. Whether PET-measured synchrony can offer diagnostic value beyond or at an earlier stage than mainstream functional parameters, may serve as a tool for refining selection of CRT recipients, and should be incorporated in the clinical exercise of risk stratification, remains to be elucidated. The application of PET synchrony evaluation together with the evaluation of myocardial scar (fibrosis) has the potential to improve selection for access to CRT in those patients most likely to improve the clinical effectiveness and cost effectiveness of CRT for heart failure.Notably, the intrinsic advantages of PET, including its wide range of physiological radiotracers available and its full quantitative capabilities, set the ground for the value addition to the phase analysis of ventricular synchrony in establishing the so-called “one-stop shop”Evaluation of PET ventricular mechanical synchrony has arguably emerged as an extrapolation of prior phase analysis using SPECT imaging. As such, there are variations in reference values, and extensive evidence on its utility for the evaluation of ventricular dysfunction with diagnostic and prognostic purposes as well as for better selection of CRT recipients is slowly emerging.The evaluation of mechanical ventricular synchrony through phase analysis of gated acquisitions represents a value addition to modern cardiac PET imaging. Cardiac PET synchrony may be useful in the assessment of patients with CAD, in the evaluation of prognosis in patients with cardiac dysfunction, and in the optimization of patient selection for advanced therapies such as CRT.Supplementary material 1 (PPTX 2062 kb)Below is the link to the electronic supplementary material.


Isotropic high-resolution three-dimensional (3D) magnetic resonance neurography (MRN) is increasingly used to depict even small and highly oblique nerves of the lumbosacral plexus (LSP). The present study introduces a T2 mapping sequence (T2-prepared 3D turbo spin echo) that is B1-insensitive and enables quantitative assessment of LSP nerves.In this study 15 healthy subjects (mean age 28.5 ± 3.8 years) underwent 3 T MRN of the LSP area three times. The T2 values were calculated offline on a voxel-by-voxel basis and measured at three segments  of three LSP nerves  by two independent investigators (experienced and novice). Normative data for the different nerves were extracted and intraclass correlation coefficients (ICCs) were calculated to assess reproducibility and interobserver reliability of T2 measurements.The T2 mapping showed excellent reproducibility with ICCs ranging between 0.99 (S1 preganglionic) and 0.89 (L5 postganglionic). Interobserver reliability was less robust with ICCs ranging between 0.78 (S1 preganglionic) and 0.44 (L5 postganglionic) for S1 and L5. A mean T2 value of 74.6 ± 4.7 ms was registered for preganglionic segments, 84.7 ± 4.1 ms for ganglionic and 65.4 ± 2.5 ms for postganglionic segments, respectively. There was a statistically significant variation of T2 values across the nerve (preganglionic vs ganglionic vs postganglionic) for S1, L5, and L4.Our approach enables isotropic high-resolution and B1-insensitive T2 mapping of LSP nerves with excellent reproducibility. It might reflect a robust and clinically useful method for future diagnostics of LSP pathologies.The online version of this article (10.1007/s00062-017-0658-9) contains supplementary material, which is available to authorized users. Magnetic resonance neurography (MRN) has shown to be a powerful diagnostic tool that enables the localization and characterization of nerve pathologies . EspeciaMost previous studies using high-resolution 3D MRN of plexus nerves have focused on qualitative assessments of T2-weighted signal alterations while quantitative investigations are still mostly lacking . AlthougThe study protocol was approved by the local ethics commission (registration number: 408/15S) and was carried out in accordance with the Declaration of Helsinki. Written informed consent was obtained from all subjects prior to imaging.A total of 15 healthy subjects  without any history of neurological or lumbar spinal diseases underwent MRN on a 3 T whole-body magnetic resonance scanner . The MRN was performed three times in total in each volunteer on the same day with a short break between the single scans, including repositioning of the subject.3, acquisition voxel 2 × 2 × 2 mm3, echo train length 80, T2 preparation durations of 20/40/60/80 ms, fat suppression spectral attenuated inversion recovery (SPAIR) and a scan duration of 6:48 min with a repetition time (TR) of 1.6 s and an effective echo time (TE) of the TSE shot of 15 ms. The flip angle train of the TSE readout was designed in order to achieve a constant signal plateau throughout 80% of the TSE shot duration for white matter [The LSP of the subjects was scanned with a 16-channel torso coil array and the built-in-table posterior 12-channel coil array. First, a flow-suppressed (2 mm isotropic voxel size) T2-weighted 3D TSE sequence was performed to depict plexus anatomy . Second,e matter .https://www.horosproject.org). In short, the S1, L5, and L4 nerves of both sides were identified, and a standardized color scheme was applied to the T2 maps  and golden section search , 11. TheThe described approach of ROI positioning and measurement of T2 values was performed independently by two investigators. The first investigator  evaluated all three scans of the subjects to assess reproducibility, whereas the second investigator  evaluated the first scan of each subject to explore interobserver reliability. The two observers were strictly blinded to the measurements of the other, and the first observer was furthermore blinded to the T2 values of the first or first and second scan when performing measurements in the second or third scan of a respective subject. Observer 1 evaluated the first scan in each subject first, followed by a second and third round of analyses using the subjects’ second and third scans. The interval between the three analysis sessions was at least 2 weeks. Mean T2 values >100 ms were removed from the datasets prior to statistical analyses because high T2 values most likely stem from measurements in areas with high fractions of cerebrospinal fluid (CSF) or surrounding vessels.p < 0.05 for all statistical testing.For statistical data analyses, GraphPad Prism  and SPSS  were used. The level of significance was set at The T2 measurements for S1, L5, and L4 of both sides extracted from the ROIs were collapsed by calculating the average of the corresponding right-sided and left-sided values  for preganglionic, ganglionic, and postganglionic measurements, respectively. This was done separately for the values of observers 1 and 2, and descriptive statistics were calculated based on the collapsed values obtained. During this step, the portion of removed measurements due to T2 values >100 ms was documented.Based on the mean T2 values (right-sided and left-sided T2 measurements collapsed), intraclass correlation coefficients (ICCs) were calculated to assess reproducibility and interobserver reliability  for the different nerves and their segments. For reproducibility, three scans in each subject, all evaluated by observer 1, were considered, whereas the first scan of each subject was evaluated independently by both observers to evaluate interobserver reliability. Furthermore, coefficients of variation (CVs) were calculated as measures for dispersion regarding the T2 values. The mean T2 values (right-sided and left-sided T2 measurements collapsed) for preganglionic, ganglionic, and postganglionic measurements of the three scans in each subject were averaged to generate one T2 value for each of these segments for S1, L5, and L4, respectively. These segment-specific values were compared by Kruskal-Wallis test followed by Dunn’s multiple comparisons test for S1, L5, and L4.The MRN was successfully performed three times in each subject (3 × 15 = 45 scans). None of the scans had to be excluded due to artifacts according to visual image quality assessment. Observer 1 evaluated three scans in each subject with respect to preganglionic, ganglionic, and postganglionic T2 values of S1, L5, and L4 nerves of both sides (3 × 15 × 3 × 3 × 2 = 810 T2 measurements). Of these measurements, 63 (7.8%) were excluded due to T2 values >100 ms . Furthermore, observer 2 evaluated the first scan in each subject, again separately for preganglionic, ganglionic, and postganglionic T2 values of S1, L5, and L4 nerves of both sides (1 × 15 × 3 × 3 × 2 = 270 T2 measurements). Also 32 measurements (11.9%) were removed due to T2 values >100 ms . Mean T2 values (right-sided and left-sided T2 measurements collapsed) according to evaluation of the three scans per subject by observer 1 can be found in Table p = 0.0240; pre- vs. postganglionic: p = 0.0320, ganglionic vs. postganglionic: p < 0.0001; Fig. p = 0.0346; pre- vs. postganglionic: p = 0.0072, ganglionic vs. postganglionic: p < 0.0001; Fig. p = 0.0152; pre- vs. postganglionic: p = 0.0191, ganglionic vs. postganglionic: p < 0.0001; Fig. When averaging the T2 values derived from three scans measured by observer 1, S1 showed values of 74.5 ± 6.4 ms , 86.3 ± 6.2 ms , and 65.0 ± 3.0 ms , with statistically significant differences between these measurements , the dataset analyzed remains considerably large, and the potential usefulness of our approach is reflected by excellent reproducibility. In this context, ICCs of at least 0.89 for all analyzed nerves and segments were observed  enables B1-insensitive and isotropic high-resolution T2 mapping of LSP nerves. This approach allowed measurements of the spatial variation of T2 values of different nerves  within different segments  in healthy subjects, thus providing normative data with excellent reproducibility. The T2 mapping approach using T2-prepared 3D TSE might reflect a robust method for future diagnostics of LSP pathologies.Characteristics of the T2-prepared 3D TSE sequence


Introduction: Ischemic mitral regurgitation (IMR) is common after acute myocardial infarction(AMI) which is associated with long-term cardiovascular mortality. Size, transmurality andlocation of the myocardial infarction (MI) has role on the development of IMR. In this study weevaluated the severity of IMR after different types of MI.Methods: One-hundred patients with the first AMI were recruited and according toechocardiographic findings were categorized to have moderate to severe IMR or trivial or no IMR . Demographic and echocardiographic findings and MIlocation were compared between groups.Results: Case group compared to control group had significantly higher Killip class, more caseswith left ventricular ejection fraction (LVEF) <30% and inferolateral STEMI. They had significantlyhigher left ventricular (LV) and right ventricular (RV) diastolic dysfunction. Mechanism of IMRwas mono leaflet tethering in 88%, both leaflets tethering in 12% and ring dilatation in 62%. MRjet origin-direction was medial commisure-posterior in 66%, lateral commisure-anterior in 1122% and both commisure-central direction in 12%.Conclusion: IMR is common after AMI, especially in cases with inferior MI. The echocardiographicfindings are indicative of left ventricular remodeling and abnormality of mitral valve apparatus. We evaluated the prevalence of IMR and its severity in patients with AMI and its association with the infarct location and clinical condition.Studies have shown that the incidence of IMR in inferior MI is higher than other types, but the outcome is worse for anterior MI.One hundred patients over 18 years with first time AMI including 50 patients with moderate to severe IMR (case group) and 50 patients with mild or no IMR (control group) admitted to Shahid Madani hospital during 2011-2012 were recruited. Exclusion criteria was previous MI and percutaneous transluminal coronary angioplasty (PTCA), performing PTCA before echocardiography during the admission, previous coronary artery bypass surgery (CABG), history of chordae or papillary muscle rupture, valvular or congenital heart disease.Baseline demographic, clinical and procedural data was recorded for each patient; also, the infarction size and type of AMI (STEMI or NSTEMI and anterior vs inferior STEMI) were recorded according to ECG findings.All patients underwent transthoracic echocardiography at rest using Vivid 7 cardiovascular ultrasound system  during the first 5 days after AMI. Echocardiographic findings including left ventricular ejection fraction (LVEF), regional wall motion abnormality (RWMA), wall motion score index (WMSI), mitral inflow, left atrium, left ventricle and right ventricle sized were measured.When the valve structure intrinsically were normal and the regurgitation was caused as a result of the STEMI, the ischemic MR was diagnosed. Control group had no IMR, trivial IMR or mild (MR<2+) and cases had moderate or severe MR (MR≥2+).7 Degree and severity of MR was assessed semi quantitatively and quantitatively using the proximal isovelocity surface area method, effective regurgitant orifice area, jet eccentricity, and jet area to atrial area, also measured the vena contracta width. The regurgitant volume, fraction, and orifice area were calculated via the volumetric or the proximal isovelocity surface area method.4Modified biplane Simpson method was used to measure LV volume. LVEF was calculated from the LV end-diastolic and end-systolic volumes. WMSI was measured adding and dividing scores of regional wall motion of the all 17 LV segments. From the end systolic apical 4-chamber view, the LV sphericity was calculated by using the LV short-axis/long-axis dimension ratio. The prolate ellipsoid model was used to assess LAVI. Diastolic early filling velocity (E) wave, late diastolic velocity (A) wave, E/A ratio and DCT were measured via pulsed wave Doppler mitral inflow velocities. A restrictive LV filling pattern was defined as an E/A ratio >2, with a deceleration time of <150 ms. Also myocardial systolic (Sa), early diastolic (Ea), late diastolic (Aa) velocities, and E/E’ ratio were measured and averaged via pulsed wave TDI after placement of the sample volume at the level of the lateral and septal mitral annuli.Measuring diastolic function and defining the grade of diastolic dysfunction according to conventional grading in MR is complicated due to the distortion in E and A velocities and E/A ratio. In these cases, other echocardiographic data such as DCT and findings of tissue Doppler (E/E’ ratio) also were used to evaluate the diastolic function.t test were used to compare data between groups. P values <0.05 were considered statistically significant.All data were analyzed using SPSS 15 software. The results are expressed as Mean ± standard deviation (SD) or percentage. Chi-square test, Fischer exact test and independent Patients’ baseline findings between groups are shown in Case group had significantly higher LVESV, LVESVI, LVEDV, LVEDVI, WMSI, LAD, MVEV, MV annulus size and index, inter-papillary muscle distance (systolic) and PAP and lower MVDCT, MV E/A, MV annulus excursion, inter-papillary muscle distance ratio and TV excursion . Tissue Mechanism of IMR in case group was mono leaflet tethering in 44 cases, both leaflets tethering in 6 cases and ring dilatation in 31 cases. MR jet origin-direction was medial commisure-posterior in 33 (66%), lateral commisure-anterior in 11 (22%) and both commisure-central direction in 6 (12%).P = 0.04) and RV diastolic dysfunction .Case group compared to control group had significantly higher LV , calculated with PISA and Doppler methods, is a criterion of MR severity independent of hemodynamic state and also an independent predictor of prognosis. EROA ≥20 mm2 & tethering depth ≥1 cm are indicative of severe MR,16 and we reached the similar results. On the other hand, an elevated RV systolic pressure, LA and LV enlargement, an increased E wave velocity are also supportive of significant MR. The most scientific and accurate method is integration of the sum of all these measures. In fact, according to the sum of the available data, MR was more sever in case group.Severity of MR could be measured by different methods including distal jet area, vena contracta, proximal isovelocity surface area (PISA) method, volumetric, continuous wave Doppler pattern, tenting area and tethering depth (height). Previous studies have indicated that tenting area ≥1.5 cm8 Fazlinezhad and colleagues10 reported higher grade of diastolic dysfunction, end-diastolic LV pressure in IMR cases. They also had higher Systolic Pulmonary Artery Pressure (SPAP) which was related directly to the severity of MR. MacHaalany et al9 also showed higher prevalence of PAP, LVESD and LA size in moderate to severe IMR. However, in the Lamas et al study,15 the patients with IMR and those without MR had similar LV filling pressures.Different echocardiographic findings are reported in cases with moderate to severe IMR. It is reported that moderate and severe MR in acute MI is related to increased left ventricular diastolic dimensions.In our study, the mean value of LVEDV, LVEDVI, LVESV and LVESVI are mild to moderately enlarged which are predictable considering the local remodeling as a consequence of RWMA and papillary muscle displacement in inferior MI. Observing monoleaflet tethering in most patients in case group is also indicative of local remodeling, as in case of global remodeling we observe bileaflet tethering. Along with these findings, having Ant MI in 20% of cases could be effective in the increase in the volumes.18 Also, IMR is more likely to occur in the inferior MI that anterior MI.19 The higher incidence of IMR in inferior MI is reported in previous studies.17It is reported that the occurrence and severity of the IMR is affected by the location of MI; the mechanism producing IMR is different in anterior compared with inferior STEMI. Although LV remodeling and global LV dysfunction is greater in anterior MI, IMR is more severe in inferior STEMI due to the increased tethering force of the posteromedial papillary muscle near the site of the infarction.20 and receiving thrombolytic therapy or late PCI may increase the rate of IMR.Similarly in our study, we observed that inferolateral MI was higher in moderate to severe IMR. This group also received less streptokinase. It is reported previously that primary PCI lowers the incidence of MR in STEMI patients,We only included 50 cases with IMR and 50 cases without IMR which could cause selection bias. Most patients underwent PCI in the few first days after MI and before we could evaluate them by echocardiography; so they were excluded. The study sample was also low and could limit our analysis.IMR is common after AMI, especially in cases with inferior MI. The echocardiographic findings are indicative of left ventricular remodeling and abnormality of mitral valve apparatus.All patients gave informed written consent and the ethics committee of Tabriz University of Medical Sciences approved the study protocol.None.This study was supported by a grant from Cardiovascular Research Center, Tabriz University of Medical Sciences, Tabriz, Iran. Authors have no other funding support to disclose.