***TASK*** the task is to summarize an input biomedical literature in six sentences 
    ***INPUT*** the input is a biomedical literature 
    ***OUTPUT*** the output is the summary of an input biomedical literature in six sentences 
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    Input: Background —The relation between left ventricular ( LV ) remodeling and ventricular arrhythmias after myocardial infa rct ion is poorly documented . We investigated the relations between LV size , hypertrophy , and function and ventricular arrhythmias in 263 patients from the Survival and Ventricular Enlargement ( SAVE ) study , using quantitative 2D echocardiography and ambulatory ECG monitoring after myocardial infa rct ion . Methods and Results —Transthoracic 2D echocardiograms and arrhythmia monitoring were performed at baseline ( mean , 11 days ) and 1 and 2 years after infa rct ion . LV size , short-axis muscle ( mass ) area ( LVMA ) , and function were quantified from 2D echocardiograms . The prevalence of ventricular tachycardia ( VT ) and frequent ventricular ectopy ( premature ventricular contractions [ PVCs ] > 10/h ) was assessed from ambulatory ECG . VT and PVCs > 10/h occurred in 20 % and 29 % of patients at baseline , in 22 % and 35 % at 1 year and 23 % and 39 % at 2 years , respectively . VT and PVCs > 10/h at baseline and 1 and 2 years were significantly related to LV size , LVMA , and function . Furthermore , changes in LV size and function from baseline to 2 years predicted both VT and PVCs > 10/h . The study was underpowered to detect treatment effect of ACE inhibitors and & bgr;-adrenergic receptor blockers but did not alter the relations between ventricular arrhythmias , LV size , and function . Conclusions —Quantitative echocardiographic assessment of LV size , LVMA , and function and changes in these measurements over time predict ventricular arrhythmias after infa rct ion . Altered LV architecture and function during postinfa rct ion LV remodeling provide an important substrate for triggering high- grade ventricular arrhythmias Purpose To prospect ively compare the usefulness of myocardial perfusion and deformation imaging for the prediction of functional recovery and left ventricular ( LV ) remodeling in patients with ST-elevation myocardial infa rct ion ( STEMI ) . Methods We prospect ively examined 36 patients with reperfused STEMI , 12±9 h after primary angioplasty and stent placement .  LV function was reevaluated at 4–6 months of follow-up , to assess relative improvement of LV-ejection fraction ( ΔEF% ) and increase in end-diastolic volume ( ΔEDV ) . Results During the follow-up period , 19 of 36 patients showed LV function improvement ( ΔEF%≥10 % ) , whereas 10 patients had LV remodeling ( ΔEDV≥20 % ) . Peak negative strain ( ϵpeak ) , peak negative strain rate ( SRpeak ) , and myocardial blood flow ( A × &bgr ; ) correlated with ΔEF% ( r=−0.55 , −0.57 , and 0.46 , respectively , P<0.01 for all ) , and allowed for prediction of LV remodeling on an individual level ( area under the curve of 0.85 for strain rate , 0.95 for strain , and 0.90 for regional blood flow , P<0.001 for all ) . The combined assessment of myocardial perfusion and deformation correctly predicted LV remodeling in four additional patients , compared with each technique separately . Conclusion Contrast echocardiography , strain Doppler imaging , and possibly the combination of both are useful for the prediction of adverse LV remodeling and for the early risk stratification of patients with STEMI A minority of patients experience progression to clinical ly significant left ventricular dysfunction and enlargement after myocardial infa rct ion ( 1 ) . However , patients with worsening left ventricular function after myocardial infa rct ion are at significantly greater risk for congestive heart failure and death ( 2 , 3 ) . Advances in the care of acute myocardial infa rct ion over the past decadeparticularly the use of mechanical and pharmacologic reperfusion therapieshave reduced the risk for left ventricular dysfunction ( 4 ) and improved morbidity and mortality after myocardial infa rct ion ( 5 ) . Improvements in left ventricular function can be apparent shortly after myocardial infa rct ion and have generally been attributed to recovery from myocardial stunning ( 6 ) . However , the great heterogeneity in patients after myocardial infa rct ion underscores the importance of identifying factors that influence the progression and regression of left ventricular dysfunction . The Healing and Early Afterload Reduction Therapy ( HEART ) trial ( 7 ) was a r and omized , double-blind study of the hemodynamic effects of early versus delayed administration of three regimens of ramipril , an angiotensin-converting enzyme ( ACE ) inhibitor , after myocardial infa rct ion . Patients were followed by performing serial echocardiography within the first 24 hours after myocardial infa rct ion and at 14 and 90 days after myocardial infa rct ion . Patients treated with ramipril experienced significant improvements in ejection fraction at 14 days after myocardial infa rct ion , but all echocardiographic measures of ventricular size and function were similar in the three treatment groups by 90 days ( 7 ) . The present analysis assessed clinical and echocardiographic predictors of recovery of ventricular function in the 88 % of patients in HEART who underwent reperfusion therapy ( 65 % received thrombolysis alone , 15 % had percutaneous transluminal coronary angioplasty alone , and 8 % had both ) . Methods Patients The HEART study enrolled 352 patients with acute anterior Q-wave myocardial infa rct ion . Patients with ST-segment elevation or new Q waves in two or more contiguous leads were also eligible . Patients underwent echocardiography within 24 hours after myocardial infa rct ion ( before r and omization [ day 1 ] ) and at 14 and 90 days after myocardial infa rct ion . Patients were r and omly assigned to receive one of three dosing regimens of ramipril : placebo for 14 days , followed by full-dose ( 10 mg ) ramipril ; low-dose ( 0.625 mg ) ramipril for 90 days ; or full-dose ramipril for 90 days . Thus , by day 14 , all patients were treated with ACE inhibition . Inclusion and exclusion criteria and details of the titration scheme and patient characteristics are described elsewhere ( 7 ) . Serial echocardiographic data from days 1 , 14 , and 90 were available in 249 patients . Baseline data were available for an additional 12 patients who died during follow-up . Patients with day-1 echocardiograms of insufficient quality and those who were alive at 90 days but for whom echocardiograms at this time point were not available were excluded from analysis . Of the 352 patients enrolled in the study , 48 did not have echocardiograms of sufficient quality for analysis , and 18 ( including 13 who died ) did not have all three echocardiograms . We also excluded 25 patients who did not receive reperfusion therapy .  Echocardiographic Analysis Echocardiographic measurements were made in triplicate by using a Nova Microsonics ( Mahwah , New Jersey ) workstation , as described elsewhere ( 7 ) . The echocardiographic reader was blinded to treatment assignment . Endocardial borders from end-diastolic and end-systolic frames were digitized manually , and left ventricular volumes were assessed by using the Simpson rule method . Infa rct segment length was assessed by manually tracing the akinetic or dyskinetic segment and was expressed as a percentage of the endocardial perimeter . The reproducibility of the echocardiographic measurements is reported elsewhere ( 7 ) . Statistical Analysis Patients were categorized into three groups according to degree of recovery of left ventricular function . Patients were categorized as having 1 ) complete recovery of function if functional abnormalities observed on day 1 improved to normal [ left ventricular ejection fraction > 0.55 and absence of regional akinesis or dyskinesis ] , 2 ) partial recovery of function if ejection fraction improved and the extent of regional akinesis or dyskinesis decreased from day 1 , or no 3 ) recovery if neither of these criteria was fulfilled or death occurred before 90 days . Left ventricular enlargement ( remodeling ) was defined as an increase in ventricular end-diastolic volume between day 1 and day 90 and was treated as a continuous variable . Univariate and multivariate logistic regression were used to assess relationships between day 1 values and recovery of function . Values are expressed as the mean ( SD ) . A P value less than 0.05 was considered statistically significant . Stata statistical software ( Stata Corp. , College Station , Texas ) was used for analyses . Results Baseline Characteristics and Left Ventricular Enlargement Clinical and echocardiographic data were obtained on day 1 before r and omization ( Table 1 ) . Included and excluded patients differed significantly only with regard to age ( 59.4 12.3 years vs. 64.2 12.9 years ; Pï¿½=ï¿½0.001 ) . Patients with partial recovery had lower ejection fraction and larger volumes than did those with no recovery or complete recovery , and patients with full recovery had shorter infa rct segments than did those with partial recovery or no recovery ( Table 1 ) . Fewer patients in the complete recovery group than in the partial or no recovery groups were diabetic , but this difference was not statistically significant . The recovery groups did not significantly differ with regard to other baseline characteristics or in the distribution of drug treatment . Table 1 . Baseline Characteristics of Patients by Recovery Group Recovery of Left Ventricular Function On day 1 , only 9 of 261 ( 3.4 % ) patients had normal ventricular function ( ejection fraction > 0.55 and no akinesis or dyskinesis ) . The change in left ventricular ejection fraction varied widely and improved by day 90 in 171 of 261 ( 66 % ) patients ( Figure 1 ) . The mean change in ejection fraction during this time was 0.045 0.098 . Most of this change occurred in the first 14 days ( mean change in ejection fraction from day 1 to 14 , 0.038 0.091 ) ; minimal additional change occurred between days 14 and 90 ( Table 2 ) . Of the 252 patients with abnormal left ventricular function on day 1 ( ejection fraction < 0.55 or any akinesis or dyskinesis ) , 13 % had complete recovery of ventricular function by day 14 and 22 % of patients had complete recovery by day 90 . An additional 36 % of patients had partial recovery of function by day 90 , defined as improvement in ejection fraction from day 1 values and shortening of the akinetic or dyskinetic segment . The remaining patients had functional deterioration ( decrease in ejection fraction or increase in the length of the infa rct segment from day 1 ; 103 patients ) or died ( 12 patients ) . At 90 days , 53 % ( 132 of 249 ) of patients had greater than 5 % improvement in ejection fraction from baseline , but only 16 % ( 39 of 249 ) had a decrease in ejection fraction greater than 5 % . The length of the infa rct segment decreased in the group as a whole from 27.0 % 10.9 % at day 1 to 19.1 % 13.1 % at day 14 and 16.9 % 13.7 % at day 90 . Figure 1 . Distribution of change in ejection fraction from day 1 to 90 . Table 2 . Echocardiographic Variables throughout the Study We previously reported a statistically significant increase in ejection fraction from day 1 to 14 in patients receiving full-dose ( 10 mg ) ramipril ( 7 ) , although ejection fraction did not differ among the groups by day 90 . In the current analysis , we found no differences in the percentage of patients with full recovery of function by day 14 or day 90 according to treatment group . In addition , recovery groups did not differ in time to reperfusion ( Table 1 ) or the proportion of patients who recovered according to type of reperfusion therapy . Predictors of Recovery of Function Baseline clinical characteristics , including age , sex , and Killip class , did not predict recovery of function . In contrast , peak creatine kinase level ( which occurred a mean of 27 17 hours after onset of symptoms ) , a crude assessment of the extent of necrosis , and left ventricular function on day 1 ( ejection fraction and extent of akinesis or dyskinesis ) were significant predictors of recovery of function in univariate and multivariate analyses . The percentage of patients with complete recovery of function decreased as the creatine kinase quartile increased ( P for trend < 0.001 ) ( Figure 2 ) . In a multiple logistic regression analysis that included peak creatine kinase level , baseline ejection fraction , infa rct segment length , Killip class , age , sex , and drug therapy , peak creatine kinase level remained the strongest independent predictor of recovery . Each 100-unit increase in creatine kinase level was associated with a 4.3 % decreased odds of full recovery ( Pï¿½=ï¿½0.001 ) . Figure 2 . Percentage of patients with complete recovery of function by increasing quartile of peak creatine kinase level . P Left Ventricular Enlargement and Recovery of Function Overall , left ventricular en 
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This systematic review suggests that STE is associated with changes in LV volume or function regardless of underlying mechanisms and deformation direction .
Meta-regression demonstrates a strong association between peak longitudinal systolic strain and adverse remodeling .