aortic valve stenosis is a quite frequent valvular disease which could require surgical treatment [ 1 , 2 ] . aortic valve replacement by open chest surgery is still considered the gold standard for symptomatic patients , but recently transcatheter aortic valve implantation ( tavi ) has become an option for patients at high surgical risk . for one third of these patients , not accepted for surgical treatment due to advanced age , comorbidities , and high surgical risk , medical evidence suggests that tavi is feasible and provides a hemodynamic and clinical improvement up to two years , even if long - term durability is still debated . aortic stenosis causes increased left ventricular ( lv ) afterload , which leads to lv hypertrophy and remodeling towards heart failure , increased morbidity and mortality . surgical treatment , on the one hand , has already been demonstrated to reduce lv mass and improve systolic and diastolic lv parameters , thus prolonging survival . tavi , on the other , seems to improve diastolic function and to favor left ventricular mass regression ( lvmr ) after six months . the impact of the procedure on lv systolic parameters like peak longitudinal strain have not yet been extensively evaluated . the aim of the present study was to assess lvmr and peak longitudinal strain improvement six months after tavi compared to pre - procedural assessments . moreover , we wanted to investigate whether longitudinal strain parameters before the procedure could predict lvmr . subjects . from january 2011 to august 2011 we consecutively enrolled 23 patients with pure symptomatic severe aortic stenosis and left ventricular ejection fraction > 45% who underwent successful tavi at the cardiologic unit of university civil hospital of brescia , italy . exclusion criteria were : history of ischemic heart disease , high blood pressure , hypertensive cardiomyopathy , dilated cardiomyopathy , and congenital heart defects . patients were treated with tavi if the aortic valve area was 2 , if the european system for cardiac operative risk evaluation score ( euroscore ; supplementary data online , appendix s1 )   was > 20% or if one or more of the following criteria was met : contraindication for surgery , severely reduced pulmonary function , liver cirrhosis , or metastatic cancer . all patients underwent the tavi procedure with a third - generation self - expanding corevalve prosthesis ( medtronic , minneapolis , mn ) . the procedure was performed at the catheterization laboratory under local anesthesia and mild sedation with fluoroscopy guidance . procedural success was defined as implantation of a functioning aortic prosthesis valve without intraprocedural mortality and with a paravalvular leak < 2 . we state that our study complies with the declaration of helsinki and that all patients gave their informed written consent to access their data for scientific purposes . the arm in which the highest sitting diastolic pressures were found was the arm used for all subsequent readings throughout the study . every effort was made to have the same staff member obtain blood pressure measurements in each individual patient , at the same time of day , using the same equipment . systolic pressure was recorded when the initial sound was heard ( phase i of the korotkoff sound ) , while diastolic pressure was recorded at the disappearance of the sound ( phase v of the korotkoff sound ) . echocardiograms were done using vivid 7 ( general electric medical systems , milwaukee , wi , usa ) equipment using a 3.5 mhz transducer , with the patients in the left lateral decubitus position , in accordance with the standardization of the american society of echocardiography . digital loops were stored on the hard disk of the echocardiograph for on - line and off - line analyses and transferred to a workstation ( echopac ; ge health - care , waukesha , wi , usa ) for off - line analysis . the echocardiographic measurements of the left ventricular end - diastolic diameter ( lvedd ) , interventricular septal thicknes ( ivst ) , and posterior wall thickness ( pwt ) were performed off - line according to recommendations of the american society of echocardiography . left ventricular volume and ejection fraction were obtained by the modified biplane simpson method . lv mass was calculated according to the formula : 0.8 x [ 1.04 x ( lvedd + pwt + ivst)3 - lvedd3 ] + 0.6 ( g ) , and indexed for body surface area . lvmr was defined as the difference between lv mass index for body surface area after six months and before the procedure . end - diastolic relative wall thickness was the ratio of 2 x pwt / lvedd . aortic valve area was calculated by the continuity equation , and the maximum pressure gradient across the restrictive orifice was estimated by the modified bernoulli equation . mean transaortic pressure gradient was calculated by averaging the instantaneous gradients over the ejection period on the continuous - wave doppler recordings . the assessment of longitudinal peak systolic strain was performed offline to the apical two - chamber , four - chamber , and long - axis views of the left ventricle . in brief , the endocardial contour was manually traced at an end - systolic frame . the software then automatically traced a concentric region of interest including the entire myocardial wall . strain analysis was performed by dividing each lv image into six segments per view . with the beginning of the qrs complex and the aortic valve closure time as reference points , systolic global longitudinal strain was calculated by averaging the peak systolic values of the 18 segments [ 20 , 21 ] . all analyses were carried out using ibm spss statistics 20 for windows ( spss , inc . , continuous variables were tested for normality with the kolmogorov - smirnov test and are represented by mean  standard deviation , while categorical variables are represented as frequency ( n ) and percentage of the sample . paired - samples student s t - test and wilcoxon signed rank test were performed to analyze the difference between means for continuous variables between baseline and 6-month follow - up , and 2 test was performed to assess the difference between proportions for categorical variables ( fisher s exact test if dichotomic ) . bivariate spearman s correlation and linear regression were run between lv strain parameters at baseline and lvmr to investigate their predictive value . mean age was 838 years , ten patients were male ( 43.5% ) and the logistic euroscore was 24.915.1% . one patient was in new york heart association ( nyha ) class i ( 4.3% ) , seven in nyha class ii ( 30.5% ) and 15 in nyha class iii ( 65.2% ) . the peak and mean baseline transvalvular gradients were 8821 mmhg and 5616 mmhg , respectively . calculated aortic valve area index at baseline was 0.330.15 cm / m . at six months of follow - up nyha class improved with ten patients in nyha class i ( 43.5% ) , 12 in nyha class ii ( 52.2% ) , and three in nyha class iii ( 4.3% ) ( p<0.001 ) ( table 2 ) , while systolic blood pressure increased from 1159 to 1228 ( p=0.024 ) and diastolic pressure from 786 to 836 ( p=0.031 ) . lv = left ventricular ; ivst = interventricular septal thicknes ; pwt = posterior wall thickness ; lvedd = left ventrhicular end - diastolic diameter . a complete study data set was available for all patients : the echocardiographic parameters evaluated at baseline and during follow - up of six months are summarized in table 2 and figure 1 . there were significant periprocedural reductions in peak ( to 177 mmhg ; p<0.001 ) and mean ( to 105 mmhg ; p=0.005 ) transvalvular gradients . lv ejection fraction improved from 566% to 5811% without reaching statistical significance ( p=0.626 ) , as well as lvedd index ( p=0.079 ) . vice versa , ivst and pwt significantly decreased in six months ( p < 0.001 for both ) . the distribution of the lvmr grade is shown in figure 2 . left ventricular mass regression six months after tavi . there were no gender - related differences in lvmr , being -2716% in males and -2012% in females ( p=0.376 ) . bivariate correlations between lvmr and lv longitudinal strain parameters at baseline are shown in table 3 and figure 3 , while linear regression in table 4 . scatter plots of lvmr and lv longitudinal strain parameters at baseline ( a = peak longitudinal strain 2 chambers ; b = peak longitudinal strain 3 chambers ; c = peak longitudinal strain 4 chambers ; d = global longitudinal strain ) . lv hypertrophy in aortic stenosis is an adaptive mechanism to ensure a normal relation between systolic wall stress and ejection fraction . nevertheless , it has widely been associated with impaired long - term survival , myocardial infarction , sudden death , heart failure , and cerebrovascular accidents . therefore , lvmr is an important target in this kind of patient , due to the influence of residual lv hypertrophy on long - term survival [ 27 , 28 ] . lvmr ensues after the relief of lv outflow obstruction following aortic valve replacement , which leads to subsequent improved hemodynamics , clinical status , and prognosis . strain imaging is the most appropriate method to assess lv myocardial contractility as it is able to catch subclinical changes in lv performance in aortic stenosis patients [ 32 , 33 ] . in fact , peak longitudinal strain is reduced with increasing severity of aortic stenosis   and , in addition , increased lv mass and higher relative wall thickness are associated with reduced lv regional and global myocardial deformation assessed by 2d speckle tracking . as a consequence , lv global longitudinal strain improves after surgical aortic valve replacement [ 13 , 36 ] . recently demonstrated that global longitudinal strain accurately predicts lvmr in patients with pure aortic stenosis undergoing surgical treatment . this study confirms data reported by our group in 2012 regarding lv diastolic function improvement and mass reduction after tavi . moreover , to the best of our knowledge , only a very recent study analyzed lv longitudinal strain 12 months after the cited procedure . moreover , our findings seem to extend the predictive value of baseline global longitudinal strain regarding lvmr after aortic valve replacement even in the tavi context . myocardial fibrosis in an aortic stenosis heart is responsible for lack of lvmr and poor clinical outcome . in this study we confirmed the hypothesis according to which impaired global longitudinal strain before aortic valve replacement ( tavi in this case ) may be due to a certain amount of fibrosis , thus conditioning future lack of lvmr and prognosis . importantly , our study deals with patients older than cited studies ( about 15 years older than spethmann s ) . this is the reason for a more reduced lv longitudinal strain than cited studies , even if our patients had all preserved lvef and no other cardiological comorbidities . first , the small number of patients and its retrospective nature limit its strength . however , this issue reflects the rarity of patients with severe aortic stenosis who underwent tavi and without any other cardiovascular disease . second , although performed by experienced echocardiographists , lv mass measurement and epicardial / endocardial border tracing for 2d strain analysis might be affected by potential errors . fourth , the small number of patients prevented us from carrying out a multivariate approach . in conclusion , baseline global longitudinal strain seems to predict lvmr in patients with pure aortic stenosis undergoing tavi . the assessment of global longitudinal strain , in addition to other echocardiographic parameters , may be helpful in detecting patients undergoing tavi who are unlikely to benefit from it .