non - st - segment elevation acute coronary syndromes ( nste - acs ) are the most frequent manifestation of acute coronary syndromes ( acs ) .
its morbidity and mortality stays high and even equal to those of patients with st - segment elevation myocardial infarction ( stemi ) during long - term follow - up.1)2 ) current guidelines2)3 ) propose risk stratification for tailoring treatment in patients with nste - acs . in patients with intermediate- to very high - risk nste - acs , routine invasive diagnostics and treatments are recommended .
multivessel coronary disease ( mvd ) , a leading pathological foundation of intermediate to very high risk clinical manifestation , accounts for approximately 3040% nste - acs cohorts overall and is usually treated with invasive interventions.4 ) the american college of cardiology / american heart association guidelines provide a class iib recommendation that multivessel percutaneous coronary intervention ( pci ) , in contrast to culprit - only pci , might be reasonable in nste - acs patients undergoing pci ( level of evidence : b).3 ) this recommendation is based on reports of studies suggesting that multivessel pci is superior to culprit vessel only pci in terms of repeat revascularization.5)6)7)8 ) however , there is still uncertainty as to whether non - culprit lesions should be treated at the time of culprit - lesion pci for nste - acs.3 ) in the present study , we sought to examine clinical outcomes of " one - time " versus staged multivessel stenting in intermediate to very high - risk nste - acs patients with mvd .
between november 2008 and november 2012 , a total of 12047 unselected patients who had undergone a pci were prospectively registered in the pci database of general hospital of shenyang military region .
the database contained comprehensive information including clinical and angiographic characteristics , treatment strategies and clinical outcomes .
eligible patients had at least one intermediate to very high risk criteria with indication for invasive management defined by the 2015 european society of cardiology ( esc ) guidelines for the management of nste - acs2 ) ; 3 types of very high - risk criteria include recurrent or ongoing chest pain refractory to medical treatment , and recurrent dynamic st - t wave changes particularly with intermittent st - elevation and acute heart failure ; 3 types of high - risk criteria include rise or fall in cardiac troponin compatible with myocardial infarction ( mi ) , dynamic st- or t - wave changes and global registry of acute coronary events ( grace ) score > 140 ; 7 intermediate - risk criteria include diabetes mellitus , renal insufficiency ( estimated glomerular filtration rate [ egfr ] < 60 ml / min/1.73 m ) , left ventricular ejection fraction ( lvef ) < 40% or congestive heart failure , early post - infarction angina , prior pci , prior coronary artery bypass graft ( cabg ) and grace risk score>109 and < 140 .
exclusion criteria were patients who had chronic total occlusion ; patients who had procedural failure ( i.e. , technical failure ) , including staged pci patients who had procedural failure during the index pci and scheduled for staging ; patients who had cardiac shock , haemodynamic instability , mechanical complications of mi or malignant ventricular arrhythmia ; patients who had renal dialysis or a egfr < 30 ml / min/1.73 m ; staged pci patients who had any major complication during the index procedure ; patients who had a planned staged pci > 60 days .
our final population included 1531 patients from the database having nste - acs with multivessel pci ( fig .
all patients were given oral loading doses of aspirin ( 300 mg ) and clopidogrel ( 300 - 600 mg ) prior to pci , unless they had already received antiplatelet medication .
interventional procedures were performed according to standard techniques and interventional strategies rested on the operators .
the culprit lesion was identified by operators usually based on each patient 's electrocardiogram , angiographic imaging , echocardiogram and , if available , intravascular ultrasound ( ivus ) and optical coherence tomography ( oct ) .
a lesion was considered a culprit on angiography if at least two of the following morphological features suggestive of acute plaque rupture were present : intraluminal filling defects consistent with thrombus , plaque ulceration , plaque irregularity , dissection or impaired flow.2)9)10)11 ) after the procedure , the use of aspirin lifelong was advised and clopidogrel was prescribed for 12 months .
the study was approved by the hospital ethics committee and all patients gave written informed consent .
clinical follow - up was performed via telephone or at an outpatient visit at 30 days , 6 months , and 12 months after the index procedure and annually until 3 years after the index procedure .
follow - up angiography was recommended to all patients 6 to 12 months after the index procedure , and repeat revascularization was performed , if clinically indicated .
the primary outcome was the incidence of major adverse cardiac events ( mace ) , defined as the composite of cardiac death , mi and target vessel revascularization ( tvr ) during 3-year follow - up .
secondary outcomes included mace components , the composite of cardiac death or mi , definite / probable stent thrombosis , and any repeat revascularization .
mvd was defined as the presence of a significant atherosclerotic coronary artery stenosis ( 70% diameter stenosis ) or a 50% stenosis of the left main coronary artery ( left main disease ) with additional significant stenosis ( 70% diameter stenosis ) of at least one other coronary artery assessed visually during coronary angiography.12 ) staged pci is defined as the planned pci of non - infarct vessel(s ) within 60 days of the index pci .
egfr was calculated from serum creatinine ( scr ) concentrations using the modified glomerular filtration rate estimating the equation for chinese patients with chronic kidney disease : egfr ( ml / min/1.73 m)=175(scr)(age)(0.79 if patient is female).13 ) anemia was defined as hemoglobin less than 12 g / dl for men or less than 11 g / dl for women.14 ) early invasive intervention was defined as a coronary angiography performed within 24 h of hospital admission.2 ) delayed invasive intervention was defined as a coronary angiography performed more than 24 h of hospital admission .
technical success was defined as the ability to cross an occluded or stenosed segment and successfully open the artery ( restoration of thrombolysis in myocardial infarction [ timi ] flow grade 3 ) with a residual stenosis 30% by visual analysis .
cardiac death was defined as death that could not be attributed to a non - cardiac etiology .
mi was defined as third universal definition of mi presented by the third global mi task force.15 ) tvr was determined as any repeated pci or cabg to treat a previously stented vessel .
complete revascularization was defined when no visually estimated stenosis 50% for the left main and no stenosis 70% for other major arteries and/or their major branches at discharge .
stent thrombosis was classified as definite and probable according to definitions proposed by the academic research consortium.16 ) continuous variables were expressed as meanstandard deviation ( sd ) , and categorical variables were expressed as number and/or percentages . for group comparisons , pearson chi - square test or fisher 's exact test was used for categorical variables .
student 's unpaired t - test or the mann - whitney rank - sum test , as appropriate , was used for continuous variables . to minimize the influence of confounders on outcome , we used propensity score matching analysis .
patients who underwent staged pci were matched in a 1:1 ratio with patients who underwent a " one - time " pci using the nearest neighbor matching , which were based on all available variables listed in tables 1 and 2 except grace score , ivus used , oct used , contrast volume , length of hospital , medication at discharge and dual antiplatelet therapy ( dapt ) duration . a difference of < 10% was regarded as acceptable .
time to event data with estimated event rates calculated by kaplan - meier method were compared with the log - rank test .
in addition , we performed kaplan - meier analyses at the landmark periods of 0 to 90 days and 90 days to 3 years to evaluate the effect of revascularization strategy on clinical outcomes at different time periods .
between november 2008 and november 2012 , a total of 12047 unselected patients who had undergone a pci were prospectively registered in the pci database of general hospital of shenyang military region .
the database contained comprehensive information including clinical and angiographic characteristics , treatment strategies and clinical outcomes .
eligible patients had at least one intermediate to very high risk criteria with indication for invasive management defined by the 2015 european society of cardiology ( esc ) guidelines for the management of nste - acs2 ) ; 3 types of very high - risk criteria include recurrent or ongoing chest pain refractory to medical treatment , and recurrent dynamic st - t wave changes particularly with intermittent st - elevation and acute heart failure ; 3 types of high - risk criteria include rise or fall in cardiac troponin compatible with myocardial infarction ( mi ) , dynamic st- or t - wave changes and global registry of acute coronary events ( grace ) score > 140 ; 7 intermediate - risk criteria include diabetes mellitus , renal insufficiency ( estimated glomerular filtration rate [ egfr ] < 60 ml / min/1.73 m ) , left ventricular ejection fraction ( lvef ) < 40% or congestive heart failure , early post - infarction angina , prior pci , prior coronary artery bypass graft ( cabg ) and grace risk score>109 and < 140 .
exclusion criteria were patients who had chronic total occlusion ; patients who had procedural failure ( i.e. , technical failure ) , including staged pci patients who had procedural failure during the index pci and scheduled for staging ; patients who had cardiac shock , haemodynamic instability , mechanical complications of mi or malignant ventricular arrhythmia ; patients who had renal dialysis or a egfr < 30 ml / min/1.73 m ; staged pci patients who had any major complication during the index procedure ; patients who had a planned staged pci > 60 days .
our final population included 1531 patients from the database having nste - acs with multivessel pci ( fig .
all patients were given oral loading doses of aspirin ( 300 mg ) and clopidogrel ( 300 - 600 mg ) prior to pci , unless they had already received antiplatelet medication .
interventional procedures were performed according to standard techniques and interventional strategies rested on the operators .
the culprit lesion was identified by operators usually based on each patient 's electrocardiogram , angiographic imaging , echocardiogram and , if available , intravascular ultrasound ( ivus ) and optical coherence tomography ( oct ) .
a lesion was considered a culprit on angiography if at least two of the following morphological features suggestive of acute plaque rupture were present : intraluminal filling defects consistent with thrombus , plaque ulceration , plaque irregularity , dissection or impaired flow.2)9)10)11 ) after the procedure , the use of aspirin lifelong was advised and clopidogrel was prescribed for 12 months .
the study was approved by the hospital ethics committee and all patients gave written informed consent .
clinical follow - up was performed via telephone or at an outpatient visit at 30 days , 6 months , and 12 months after the index procedure and annually until 3 years after the index procedure .
follow - up angiography was recommended to all patients 6 to 12 months after the index procedure , and repeat revascularization was performed , if clinically indicated .
the primary outcome was the incidence of major adverse cardiac events ( mace ) , defined as the composite of cardiac death , mi and target vessel revascularization ( tvr ) during 3-year follow - up .
secondary outcomes included mace components , the composite of cardiac death or mi , definite / probable stent thrombosis , and any repeat revascularization .
mvd was defined as the presence of a significant atherosclerotic coronary artery stenosis ( 70% diameter stenosis ) or a 50% stenosis of the left main coronary artery ( left main disease ) with additional significant stenosis ( 70% diameter stenosis ) of at least one other coronary artery assessed visually during coronary angiography.12 ) staged pci is defined as the planned pci of non - infarct vessel(s ) within 60 days of the index pci .
egfr was calculated from serum creatinine ( scr ) concentrations using the modified glomerular filtration rate estimating the equation for chinese patients with chronic kidney disease : egfr ( ml / min/1.73 m)=175(scr)(age)(0.79 if patient is female).13 ) anemia was defined as hemoglobin less than 12 g / dl for men or less than 11 g / dl for women.14 ) early invasive intervention was defined as a coronary angiography performed within 24 h of hospital admission.2 ) delayed invasive intervention was defined as a coronary angiography performed more than 24 h of hospital admission .
technical success was defined as the ability to cross an occluded or stenosed segment and successfully open the artery ( restoration of thrombolysis in myocardial infarction [ timi ] flow grade 3 ) with a residual stenosis 30% by visual analysis .
cardiac death was defined as death that could not be attributed to a non - cardiac etiology .
mi was defined as third universal definition of mi presented by the third global mi task force.15 ) tvr was determined as any repeated pci or cabg to treat a previously stented vessel .
complete revascularization was defined when no visually estimated stenosis 50% for the left main and no stenosis 70% for other major arteries and/or their major branches at discharge .
stent thrombosis was classified as definite and probable according to definitions proposed by the academic research consortium.16 )
continuous variables were expressed as meanstandard deviation ( sd ) , and categorical variables were expressed as number and/or percentages . for group comparisons , pearson chi - square test or fisher 's exact test was used for categorical variables .
student 's unpaired t - test or the mann - whitney rank - sum test , as appropriate , was used for continuous variables . to minimize the influence of confounders on outcome , we used propensity score matching analysis .
patients who underwent staged pci were matched in a 1:1 ratio with patients who underwent a " one - time " pci using the nearest neighbor matching , which were based on all available variables listed in tables 1 and 2 except grace score , ivus used , oct used , contrast volume , length of hospital , medication at discharge and dual antiplatelet therapy ( dapt ) duration . a difference of <
time to event data with estimated event rates calculated by kaplan - meier method were compared with the log - rank test .
in addition , we performed kaplan - meier analyses at the landmark periods of 0 to 90 days and 90 days to 3 years to evaluate the effect of revascularization strategy on clinical outcomes at different time periods .
" one - time " pci was performed in 56.1% ( 859/1531 ) , and the remaining 43.9% ( 672/1531 ) had staged pci ( of these , 80.7% [ 542/672 ] had staged non - culprit intervention during the same hospitalization and 19.3% [ 130/672 ] had planned staged non - culprit procedures after hospital discharge ) . the median delay of the staged pci was 5 days ( interquartile rang [ iqr ] , 3 - 9 days ) . as noted in tables 1 and 2 ,
male , previous mi , triple - vessel disease , and current smoking were associated with more staging .
the volume of contrast media utilized during the index procedure in the staged pci group was smaller ( 200 ml [ iqr , 150 - 220 ml ] vs. 200 ml [ iqr , 200 - 300 ml ] , p<0.001 ) though the total volume utilized in the initial procedure plus staged procedure was greater ( 400 ml [ iqr , 310 - 500 ml ] vs. 200 ml [ iqr , 200 - 300 ml ] , p<0.001 ) .
most patients took dual antiplatelet therapy ( dapt ) , which was consistent with the standard recommendation .
after propensity matching , there were no statistically significant differences in preselected variables between the two groups .
3a , mace occurred in 132 patients ( 20.8% ) in the staged group and 162 patients ( 19.7% ) in the " one - time " group during 3-year follow - up ( p=0.608 ) . rates of each component of 3-year cumulative mace were similar between both groups .
the estimated 3-year composite rate of cardiac death or mi was 7.1% in the staged pci group compared with 9.1% in the " one - time " pci group ( p=0.129 ) . in addition , no significant differences in the 3-year rates of any revascularization ( 22.3% vs. 18.6% , p= 0.083 ) and definite / probable stent thrombosis ( 1.3% vs. 1.9% , p=0.295 ) were observed . at the 90-day landmark analysis ( tables 3 and 4 , fig . 2c and fig .
3c ) , no significant differences in terms of mace , its individual components , any revascularization and definite / probable stent thrombosis were observed at the landmark period of 0 to 90 days and 90 days to 3 years . after generating a propensity score , 420 of the 672 patients who underwent staged pci were matched with a patient , respectively , who underwent a " one - time " pci .
there were no differences in preselected variables for the propensity matched subjects ( table 1 , 2 ) .
3b , at 3 years , there were no differences in mace ( 18.9% vs. 21.8% , p=0.249 ) ; whereas there was a significantly lower incidence of cardiac death or mi ( 7.0% vs. 11.1% , p=0.033 ) .
the risk for cardiac death in the staged pci group tended to be lower ( 2.5% vs. 4.8% , p=0.067 ) . other clinical outcomes including mi ( 5.0% vs. 7.7% , p=0.162 ) , tvr ( 14.9% vs. 14.5% , p=0.971 ) , any revascularization ( 20.3% vs. 20.4% ,
p=0.888 ) , and definite / probable stent thrombosis ( 1.2% vs. 2.2% , p=0.280 ) were not significantly different between the two study groups .
the results of the 90-day landmark analysis for propensity score matched patients were shown in tables 3 and 4 , fig .
the staged pci group showed a lower 90-day incidence of mace ( 1.2% vs. 3.3% , p=0.037 ) , mainly due to a lower composite rate of cardiac death or mi ( 0.7% vs. 2.6% , p=0.031 ) .
the 90-day rates of mi did not differ significantly between the 2 study groups , but it presented a trend in favor of staged pci ( 0.7% vs. 2.1% , p=0.081 ) .
for the 90-day to 3-year follow - up period , both the incidences of mace ( 17.9% vs. 19.1% , p=0.641 ) and the composite of cardiac death or mi ( 6.3% vs. 8.7% , p=0.191 ) were similar between the two groups .
cardiac death , tvr , any revascularization and definite / probable stent thrombosis did not differ significangtly between the two groups at the landmark period of 0 to 90 days and 90 days to 3 years .
" one - time " pci was performed in 56.1% ( 859/1531 ) , and the remaining 43.9% ( 672/1531 ) had staged pci ( of these , 80.7% [ 542/672 ] had staged non - culprit intervention during the same hospitalization and 19.3% [ 130/672 ] had planned staged non - culprit procedures after hospital discharge ) . the median delay of the staged pci was 5 days ( interquartile rang [ iqr ] , 3 - 9 days ) . as noted in tables 1 and 2 ,
male , previous mi , triple - vessel disease , and current smoking were associated with more staging .
the volume of contrast media utilized during the index procedure in the staged pci group was smaller ( 200 ml [ iqr , 150 - 220 ml ] vs. 200 ml [ iqr , 200 - 300 ml ] , p<0.001 ) though the total volume utilized in the initial procedure plus staged procedure was greater ( 400 ml [ iqr , 310 - 500 ml ] vs. 200 ml [ iqr , 200 - 300 ml ] , p<0.001 ) .
most patients took dual antiplatelet therapy ( dapt ) , which was consistent with the standard recommendation .
after propensity matching , there were no statistically significant differences in preselected variables between the two groups .
2a and fig . 3a , mace occurred in 132 patients ( 20.8% ) in the staged group and 162 patients ( 19.7% ) in the " one - time " group during 3-year follow - up ( p=0.608 ) . rates of each component of 3-year cumulative mace were similar between both groups . the estimated 3-year composite rate of cardiac death or mi was 7.1% in the staged pci group compared with 9.1% in the " one - time " pci group ( p=0.129 ) . in addition , no significant differences in the 3-year rates of any revascularization ( 22.3% vs. 18.6% , p= 0.083 ) and definite / probable stent thrombosis ( 1.3% vs. 1.9% , p=0.295 ) were observed . at the 90-day landmark analysis ( tables 3 and 4 , fig . 2c and fig .
3c ) , no significant differences in terms of mace , its individual components , any revascularization and definite / probable stent thrombosis were observed at the landmark period of 0 to 90 days and 90 days to 3 years .
after generating a propensity score , 420 of the 672 patients who underwent staged pci were matched with a patient , respectively , who underwent a " one - time " pci .
there were no differences in preselected variables for the propensity matched subjects ( table 1 , 2 ) .
3b , at 3 years , there were no differences in mace ( 18.9% vs. 21.8% , p=0.249 ) ; whereas there was a significantly lower incidence of cardiac death or mi ( 7.0% vs. 11.1% , p=0.033 ) .
the risk for cardiac death in the staged pci group tended to be lower ( 2.5% vs. 4.8% , p=0.067 ) . other clinical outcomes including mi ( 5.0% vs. 7.7% , p=0.162 ) , tvr ( 14.9% vs. 14.5% , p=0.971 ) , any revascularization ( 20.3% vs. 20.4% , p=0.888 ) , and definite / probable stent thrombosis ( 1.2% vs. 2.2% , p=0.280 ) were not significantly different between the two study groups .
the results of the 90-day landmark analysis for propensity score matched patients were shown in tables 3 and 4 , fig .
the staged pci group showed a lower 90-day incidence of mace ( 1.2% vs. 3.3% , p=0.037 ) , mainly due to a lower composite rate of cardiac death or mi ( 0.7% vs. 2.6% , p=0.031 ) .
the 90-day rates of mi did not differ significantly between the 2 study groups , but it presented a trend in favor of staged pci ( 0.7% vs. 2.1% , p=0.081 ) .
for the 90-day to 3-year follow - up period , both the incidences of mace ( 17.9% vs. 19.1% , p=0.641 ) and the composite of cardiac death or mi ( 6.3% vs. 8.7% , p=0.191 ) were similar between the two groups . cardiac death ,
tvr , any revascularization and definite / probable stent thrombosis did not differ significangtly between the two groups at the landmark period of 0 to 90 days and 90 days to 3 years .
to our knowledge , this is the first study to examine the efficacy of staged versus " one - time " approach in intermediate to very high - risk nste - acs patients with multivessel pci .
main findings of this study were as follow : in intermediate to very high - risk nste - acs patients with multivessel disease , staged pci was associated with a lower composite rate of cardiac death or mi compared with " one - time " pci strategy .
this benefit of staged pci was more apparent in the early period after procedures , rather than middle - late period .
clinicians are often faced with the decision of whether to treat the nonculprit lesions during the index procedure or to treat it at a later time.17 ) hannan et al .
compared the " one - time " complete revascularization in the index admission versus pci of the culprit lesion only with staged non - culprit pci for complete revascularization in a subsequent admission among patients with nste - acs and mvd.18 ) at 3 years , no significant difference in all - cause mortality was observed between the two groups .
however , the staged pci group did not include the patients who underwent a staged intervention during the same hospitalization .
furthermore , it is yet unknown whether it was different in all - cause mortality between the two groups after exclusions of low risk patients . in the current observational study ,
the superiority of staged pci strategy over " one - time " pci strategy in terms of the composite of cardiac death or mi was presented , especially in the early period after pci .
first , nste - acs patients are in a heightened thrombotic and inflammatory state.19)20)21)22 ) " one - time " multivessel pci can lead to prolongation of procedure time , exposure to a higher radiation dose23 ) and larger volume of contrast agents during the index procedure compared to staged revascularization
. this may result in an increased number of complications such as periprocedural mi or acute kidney injury as well as stent thrombosis.24)25 ) moreover , patients with high / intermediate risks of nste - acs are often in a poor clinical state or have concomitant comorbidities .
pci on the culprit lesion first and staged non - culprit pci at a later date with optimal medical therapy usually results in the patient being stable and also allows clinicians to reassess the patient 's clinical and angiographic states .
risk stratification is essential for the clinical decision - making process in nste - acs patients . with respect to outcomes ,
periprocedural complications of intervention , as well as the long - term ischemic risk , remain higher in high / intermediate risk nste - acs than in low - risk nste - acs patients.26)27)28)29)30 ) when choosing the optimal treatment strategy in the individual patient with nste - acs and mvd , general patient condition and concomitant comorbidities have to be taken into account .
however , the optimal strategy for the management of nste - acs patients with poor clinical presentation and multivessel disease has not been well established .
therefore , our patient inclusion criteria , which were based on esc guidelines , selected nste - acs patients with intermediate- to very high - risk features .
the decisions for one - time vs. staged pci were not based on a randomization but at physicians ' discretion , which resulted in obvious confounding and selection bias . although we analyzed by adjusting many possible confounding factors , unmeasured confounding or selection bias might have influenced our findings .
second , in this study , all patients underwent pci in the setting of antiplatelet therapy with clopidogrel .
third , the relatively high frequency of angiography during the period between 6 to 12 months after the procedure could bias the mace , especially tvr .
however , this bias was limited , because the two groups had similar frequencies of follow - up angiography and because repeat intervention was guided by either recurrent angina or signs of ischemia that had progressed angiographically , even without angina based on invasive or noninvasive testing . fourth , our data were collected before current practice guidelines2 ) were published .
fifth , given the low absolute number of events at 90-day follow up in the propensity score matched cohort , our study was not powered to detect significant differences in cardiac death , mi , tvr and stent thrombosis at 90 days .
last , considering follow - up angiography and routine cardiac biomarkers surveillance was not mandatory , therefore the incidence of mi might have been underestimated . in intermediate to
very high - risk nste - acs patients with multivessel disease , staged pci is superior to " one - time " pci in terms of the composite of cardiac death or mi . our findings require further confirmation by randomized trial .
in intermediate to very high - risk nste - acs patients with multivessel disease , staged pci is superior to " one - time " pci in terms of the composite of cardiac death or mi . our findings require further confirmation by randomized trial .
 background and objectivesto compare clinical outcomes of staged versus " one - time " percutaneous coronary intervention ( pci ) in intermediate to very high - risk patients with non  
 st - segment elevation acute coronary syndromes ( nste - acs ) and multivessel coronary disease ( mvd).subjects and methods1531 nste - acs patients with multivessel pci and meeting the criteria of intermediate to very high risk were screened from a prospectively registered database obtained from general hospital of shenyang military region between 2008 and 2012 . 
 they were categorized into " one - time " pci ( n=859 ) and staged pci ( n=672 ) according to intervention strategy . 
 the primary outcomes included a 3-year major adverse cardiac event ( mace ) , a composite of cardiac death , myocardial infarction ( mi ) , and target vessel revascularization.resultsat 3 years , no significant differences in mace ( 20.8% vs. 19.7% , p=0.608 ) and cardiac death / mi ( 7.1% vs. 9.1% , p=0.129 ) were observed between the two groups . after propensity score matching 
 , there was no statistical significance in mace ( 18.9% vs. 21.8% , p=0.249 ) ; whereas cardiac death / mi was significantly lower in the staged pci group ( 7.0% vs.11.1% , p=0.033 ) . 
 ninety - day landmark analysis showed that the staged pci group had a lower 90-day incidence of mace ( 1.2% vs. 3.3% , p= 0.037 ) and cardiac death / mi ( 0.7% vs. 2.6% , p=0.031 ) . for the 90-day to 3-year follow - up period , the incidences of mace ( 17.9% vs. 19.1% , p=0.641 ) and cardiac death / mi ( 6.3% vs. 8.7% , p=0.191 ) were similar in both groups.conclusionin intermediate- to very high - risk nste - acs patients with mvd , staged pci is superior to " one - time " pci in terms of cardiac death / mi . 