Attenuation of left ventricular dilatation after acute myocardial infarction by early initiation of enalapril therapy. CONSENSUS II Multi-Echo Study Group

ARNI Versus Perindopril for Remodeling in HFrEF. A Cohort Study

Introduction: Ventricular remodeling is a mal-adaptive process. Both angiotensin-converting enzyme inhibitors and sacubitril/valsartan have been shown to reverse remodeling in mostly uncontrolled observational studies. There is a lack of head-to-head studies. Methods: This cohort study compares the remodeling effects of angiotensin receptor blockers combined with a neprilysin inhibitor (ARNI) and perindopril in heart failure with reduced ejection fraction (HFrEF) patients between January 2017 and December 2020. Inclusion criteria: (i) age > 18 years, (ii) recent diagnosis of de-novo HFrEF (EF < 40%), (iii) baseline echocardiography performed not more than 2 months prior to treatment onset, and (iv) follow-up echocardiography performed not earlier than 6 months and not later than 18 months posttreatment onset. No prior treatment with renin-angiotensin-aldosterone system inhibitors was permitted in the ARNI group. Left ventricular ejection fraction (LVEF), left ventricular end-diastolic volume (LVEDV), and left ventricular end-systolic volume (LVESV) were analyzed. A two-way repeated measure ANOVA (for normally distributed) and generalized estimating equation test for nonnormally distributed interval dependent variables. Mean comparison between and within groups was performed using the Bonferroni test. Results: Following an average treatment period of 9 months, LVEF improved from 24.9% to 36.4% for ARNI and from 28.7% to 40.5% for perindopril, increments of 11.5% and 11.8% resp. (Bonferroni test [P ≤ .05]). LVEDV was reduced by 8.4 mL and 3.2 mL, and LVESV by 17.9 mL and 10.8 mL for ARNI and perindopril resp. Only the reduction of LVESV for ARNI was statistically significant (P = .007). Conclusion: Both ARNI and perindopril yielded a significant improvement in the LVEF within 9 months. The remodeling effect of ARNI seems stronger because of the greater improvements in left ventricular volumes.

Effect of early treatment with anti-hypertensive drugs on short and long-term mortality in patients with an acute cardiovascular event

BACKGROUND

Acute cardiovascular events represent a therapeutic challenge. Blood pressure lowering drugs are commonly used and recommended in the early phase of these settings. This review analyses randomized controlled trial (RCT) evidence for this approach.

OBJECTIVES

To determine the effect of immediate and short-term administration of anti-hypertensive drugs on all-cause mortality, total non-fatal serious adverse events (SAE) and blood pressure, in patients with an acute cardiovascular event, regardless of blood pressure at the time of enrollment.

SEARCH STRATEGY

MEDLINE, EMBASE, and Cochrane clinical trial register from Jan 1966 to February 2009 were searched. Reference lists of articles were also browsed. In case of missing information from retrieved articles, authors were contacted.

SELECTION CRITERIA

Randomized controlled trials (RCTs) comparing anti-hypertensive drug with placebo or no treatment administered to patients within 24 hours of the onset of an acute cardiovascular event.

DATA COLLECTION AND ANALYSIS

Two reviewers independently extracted data and assessed risk of bias. Fixed effects model with 95% confidence intervals (CI) were used. Sensitivity analyses were also conducted.

MAIN RESULTS

Sixty-five RCTs (N=166,206) were included, evaluating four classes of anti-hypertensive drugs: ACE inhibitors (12 trials), beta-blockers (20), calcium channel blockers (18) and nitrates (18). Acute stroke was studied in 6 trials (all involving CCBs). Acute myocardial infarction was studied in 59 trials. In the latter setting immediate nitrate treatment (within 24 hours) reduced all-cause mortality during the first 2 days (RR 0.81, 95%CI [0.74,0.89], p<0.0001). No further benefit was observed with nitrate therapy beyond this point. ACE inhibitors did not reduce mortality at 2 days (RR 0.91,95%CI [0.82, 1.00]), but did after 10 days (RR 0.93, 95%CI [0.87,0.98] p=0.01). No other blood pressure lowering drug administered as an immediate treatment or short-term treatment produced a statistical significant mortality reduction at 2, 10 or >/=30 days. There was not enough data studying acute stroke, and there were no RCTs evaluating other acute cardiovascular events.

AUTHORS' CONCLUSIONS

Nitrates reduce mortality (4-8 deaths prevented per 1000) at 2 days when administered within 24 hours of symptom onset of an acute myocardial infarction. No mortality benefit was seen when treatment continued beyond 48 hours. Mortality benefit of immediate treatment with ACE inhibitors post MI at 2 days did not reach statistical significance but the effect was significant at 10 days (2-4 deaths prevented per 1000). There is good evidence for lack of a mortality benefit with immediate or short-term treatment with beta-blockers and calcium channel blockers for acute myocardial infarction.

Effects of perindopril on cardiac remodelling and prognostic value of pre-discharge quantitative echocardiographic parameters in elderly patients after acute myocardial infarction: the PREAMI echo sub-study

AIMS

To determine (i) the effect of perindopril on several geometric and functional parameters of the left and right ventricles assessed by echocardiography in the unique Perindopril and Remodelling in Elderly with Acute Myocardial Infarction (PREAMI) population of post-acute myocardial infarction (AMI) elderly patients with preserved left ventricular (LV) function; and (ii) the prognostic predictors at pre-discharge derived from echo-Doppler measurements in the same population.

METHODS AND RESULTS

PREAMI included 1252 post-AMI patients (age 73 +/- 6 years, LV ejection fraction 59.1 +/- 7.7%) receiving optimal therapy after AMI, randomized to perindopril 8 mg/day (n = 631) or placebo (n = 621); n = 896 had complete echo-Doppler data. Outcome measures were clinical [death, heart failure (HF)] and standard echo-Doppler parameters. Pre-discharge LV end-diastolic volume (LVEDV) was similar: 81.1 +/- 23.1 (perindopril) and 79.6 +/- 22.7 mL (placebo). At 6 months and 1 year, LVEDV remained unchanged with perindopril (81.2 +/- 24.4 and 81.8 +/- 26.8 mL, respectively), but increased with placebo (83.0 +/- 25.3 and 83.6 +/- 25.7 mL, respectively, both P < 0.001 vs. baseline). Perindopril reduced cardiac sphericity vs. placebo (P = 0.015 at 6 months; P = 0.020 at 1 year). Classification regression tree analysis showed treatment as the most important predictor of remodelling. Multiple pre-discharge echocardiographic variables predicted the death/HF endpoint, independently of treatment (P < or = 0.05).

CONCLUSION

Remodelling occurs in post-AMI in elderly patients with normal LV function. Echo-Doppler variables at baseline have prognostic implications. Treatment with perindopril reduces progressive LV remodelling that can occur even in the case of small infarct size.

Effects of early captopril therapy after myocardial infarction on the incidence of late potentials

BACKGROUND

Late potentials (LP) on signal-averaged electrocardiography (SAECG), recorded 6 to 30 days after an acute myocardial infarction (AMI), identify patients at risk for late arrhythmic events. Angiotensin-converting enzyme (ACE) inhibitors have been shown to reduce ventricular remodeling and cardiovascular mortality after AMI.

HYPOTHESIS

The aim of this study was to investigate the effect of early (< 24 h) administration of captopril on the presence of LP on Days 6-30 after AMI.

METHODS

The study included 117 patients with a first AMI; 63 patients (53 men and 10 women, aged 59 +/- 12 years), 35 with an anterior and 28 with an inferior AMI (44 thrombolyzed), received early captopril therapy. The control group consisted of 54 age-matched patients (39 men and 15 women, aged 60 +/- 12 years), 19 with an anterior and 35 with an inferior AMI (31 thrombolyzed, p = NS), who did not receive early therapy with an ACE inhibitor. The mean left ventricular ejection fraction was similar in both groups (48 vs. 46%). Time domain analysis of SAECG was performed using a band-pass filter of 40-250 Hz. Late potentials were considered present if any two of three criteria were met: (1) Filtered QRS duration (QRSD) > 114 ms, (2) root-mean-square voltage of the last 40 ms of the QRS complex (RMS) < 20 microV, and (3) duration of low amplitude (< 40 microV) signal of the terminal portion of the QRS (LAS) > 38 ms.

RESULTS

In the two groups of patients there were no differences in mean values of SAECG parameters. No patient was receiving any antiarrhythmic drugs. In the captopril group LPs were present in 9 of 63 patients (14%) and in the control group in 17 of 54 patients (31%) (p = 0.046). There was no difference in the number of patients with a patent infarct-related artery in the two groups (76 vs. 59%).

CONCLUSION

Captopril treatment early after an AMI reduces the incidence of LPs recorded on Days 6-30 and may thus favorably affect the arrhythmogenic substrate.

European guidelines on cardiovascular disease prevention in clinical practice: executive summary. Fourth Joint Task Force of the European Society of Cardiology and other societies on cardiovascular disease prevention in clinical practice (constituted by representatives of nine societies and by invited experts)

Other experts who contributed to parts of the guidelines: Edmond Walma, Schoonhoven (The Netherlands), Tony Fitzgerald, Dublin (Ireland), Marie Therese Cooney, Dublin (Ireland), Alexandra Dudina, Dublin (Ireland) European Society of Cardiology (ESC) Committee for Practice Guidelines (CPG):, Alec Vahanian (Chairperson) (France), John Camm (UK), Raffaele De Caterina (Italy), Veronica Dean (France), Kenneth Dickstein (Norway), Christian Funck-Brentano (France), Gerasimos Filippatos (Greece), Irene Hellemans (The Netherlands), Steen Dalby Kristensen (Denmark), Keith McGregor (France), Udo Sechtem (Germany), Sigmund Silber (Germany), Michal Tendera (Poland), Petr Widimsky (Czech Republic), José Luis Zamorano (Spain)

Document reviewers: Irene Hellemans (CPG Review Coordinator) (The Netherlands), Attila Altiner (Germany), Enzo Bonora (Italy), Paul N. Durrington (UK), Robert Fagard (Belgium), Simona Giampaoli(Italy), Harry Hemingway (UK), Jan Hakansson (Sweden), Sverre Erik Kjeldsen (Norway), Mogens Lytken Larsen (Denmark), Giuseppe Mancia (Italy), Athanasios J. Manolis (Greece), Kristina Orth-Gomer (Sweden), Terje Pedersen (Norway), Mike Rayner (UK), Lars Ryden (Sweden), Mario Sammut (Malta), Neil Schneiderman (USA), Anton F. Stalenhoef (The Netherlands), Lale Tokgözoglu (Turkey), Olov Wiklund (Sweden), Antonis Zampelas (Greece)

A systematic review: Effect of angiotensin converting enzyme inhibition on left ventricular volumes and ejection fraction in patients with a myocardial infarction and in patients with left ventricular dysfunction

BACKGROUND AND AIM

To summarize and quantify results of echocardiographic studies examining the effect of angiotensin converting enzyme (ACE) inhibition on left ventricular remodelling in patients with acute myocardial infarction (MI) and in patients with left ventricular systolic dysfunction (LVSD).

METHODS

Systematic review of the literature and meta-analysis of eligible studies providing data on end-diastolic and end-systolic volumes and left ventricular ejection fraction (LVEF) were performed.

RESULTS

Data from 16 eligible studies were meta-analysed. The results of studies including patients with MI and preserved LVEF (>45%) showed no significant benefit of ACE inhibition. Results of studies/subgroups with mean LVEF < or =45% demonstrated significant differences in diastolic and systolic volumes of 3.0 (0.1, 6.0) ml and 2.25 (0.04, 4.4) ml in short-term (4-14 weeks) follow-up in favour of ACE inhibitor, p=0.041 and p=0.046 respectively. In the long-term (6-12 months) follow-up, the differences in diastolic and systolic volumes were 4.2 (0.98, 7.4) ml and 3.3 (0.9, 5.8) ml in favour of ACE inhibitor, p=0.01 and p=0.007 respectively. LVEF improved in both short and long-term follow-up, p=0.034 and p=0.021, respectively.

CONCLUSION

Chronic use of ACE inhibition has a small but sustained and beneficial effect on remodelling in patients with myocardial infarction and patients with chronic left ventricular dysfunction.

ACE inhibition in hypertension: focus on perindopril

Ongoing developments in our understanding of cardiovascular disease, together with the introduction of new drugs to treat these conditions, has led to much debate over the optimal management of hypertension. The ALLHAT study showed no major differences in cardiovascular outcome among three major classes of antihypertensive drugs. Indeed, large meta-analyses have substantiated this view, and most experts would agree that BP reduction matters more than the choice of antihypertensive agent. However, recently published data from the ASCOT-BPLA trial for hypertensive patients at moderate risk of cardiac events have caused some experts to re-evaluate this view. The recent Blood Pressure Lowering Treatment Trialists' Collaboration publication confirmed this change. In the ASCOT-BPLA trial, antihypertensive therapy based on amlodipine+perindopril significantly reduced total and cardiovascular mortality as well as other clinically relevant outcomes in comparison with a traditional strategy based on atenolol and a thiazide diuretic, despite both regimens producing nonsignificantly different reductions in brachial BP. These findings suggest that amlodipine/perindopril may exert a beneficial effect by acting on other parameters such as central BP or BP variability. ACE inhibitors have been shown to have antiatherosclerotic and antithrombogenic effects, to improve endothelial dysfunction, and to prevent cardiac remodeling in patients with coronary heart disease. In this regard, perindopril, which has relatively high affinity for ACE and true 24-hour duration of action, is one of the most extensively studied ACE inhibitors. More recent data suggest that ACE inhibitors reduce arterial stiffness, an independent risk factor for cardiovascular events, and have a beneficial effect on central aortic BP, thus providing a possible explanation for the findings of ASCOT-BPLA and confirming that ACE inhibitors are an appropriate first choice for patients with hypertension.

Perindopril

Perindopril (Coversyl) is a prodrug ester of perindoprilat, an ACE inhibitor. This agent has shown pharmacodynamic effects beyond those responsible for lowering blood pressure (BP), including the improvement of endothelial function and the normalisation of vascular and cardiac structure and function. Perindopril has a well established role in the treatment of patients with hypertension or heart failure. In the EUROPA trial, once-daily perindopril 8 mg prevented cardiovascular events in patients with stable coronary artery disease (CAD) without any apparent heart failure receiving standard recommended therapy. In the ASCOT-BPLA trial, a calcium channel antagonist +/- perindopril regimen demonstrated significant cardiovascular benefits compared with a conventional beta-blocker +/- diuretic regimen in patients with hypertension who were at risk of developing cardiovascular events. These trials demonstrate that while perindopril, in addition to standard recommended therapy, has a potential role in preventing cardiovascular events in hypertensive patients, its role in the management of patients with stable CAD is clearly established.

Inhibitory Effect of Candesartan Cilexetil on Left Ventricular Remodeling After Myocardial Infarction

Although angiotensin-converting enzyme inhibitors (ACEIs) have been shown to reduce left ventricular remodeling after acute myocardial infarction (AMI), the effects of angiotensin receptor blockers have yet to be established. This study was conducted to examine the effects of candesartan on left ventricular remodeling after AMI. Consecutive AMI patients were assigned to a candesartan group or ACEI group after successful coronary intervention. The patients in the candesartan group (n = 77, mean age, 62.8 +/- 1.3) received candesartan and the patients in the ACEI group (n = 80, mean age, 63.3 +/- 1.2) received lisinopril, enalapril, or trandolapril. Four mg was the most frequent dose in the candesartan group at 6 months. Lisinopril, enalapril, and trandolapril were administered to 52%, 27%, and 21% of the patients in the ACEI group, respectively. No significant differences in the incidences of cardiac death, nonfatal MI, or hospitalization for heart failure (P = NS) were found between the groups. The candesartan group exhibited a somewhat higher percent increase in left ventricular ejection fraction and significantly lower percent increases in left ventricular end-diastolic volume index and left ventricular end-systolic volume index compared to the ACEI group (P < 0.05, P < 0.05, respectively). Candesartan is more effective than ACEI in preventing left ventricular remodeling after AMI.

The revised role of ACE-inhibition after myocardial infarction in the thrombolytic/primary PCI era

Many studies have investigated the process of left ventricular (LV) dilatation and the effects of angiotensin-converting enzyme (ACE) inhibitors after myocardial infarction (MI). It has been generally accepted that progression of LV dilatation is a major predictor of heart failure and death after MI. Also, attenuation of LV dilatation is thought to be one of the main mechanisms by which ACE inhibitors (ACE-Is) produce their beneficial effects. However, evidence for this hypothesis came from studies that were performed before thrombolytic therapy and primary percutaneous coronary intervention (PCI) were routinely used after acute MI. Nowadays, reperfusion is obtained much more frequently and LV dilatation after MI has become less prevalent. Nevertheless, ACE-Is proved effective in reducing cardiac morbidity and mortality. Therefore, mechanisms other than attenuation of LV dilatation, such as anti-atherosclerotic effects or plaque stabilisation, may explain the long-term beneficial effects of ACE-Is after MI. In the present overview, we evaluate the role of LV dilatation and the effects of ACE-Is after MI in the thrombolytic/primary PCI era and provide recommendations on ACE-I use in clinical practice.

Influence of perindopril on left ventricular global performance during the early phase of inferior acute myocardial infarction: assessment by Tei index

The beneficial effect of angiotensin-converting enzyme inhibitors (ACE inhibitors) on left ventricular (LV) function in patients with acute myocardial infarction (AMI) is widely known. However, controversy exists about their efficacy on patients with small infarcts and preserved LV systolic function. The aim of the present study was to detect the influence of the ACE-I perindopril on the global LV performance in patients with pure inferior AMI (AMI-I) using a Doppler-derived index (DI) that combines systolic and diastolic time intervals (Tei index). Our study included 40 patients with first AMI-I, mean age 60 years +/- 9.06 years (SD) and 24 age- and gender-matched normal patients who constituted the control group (COG). Patients were randomized into two groups to receive the conventional treatment of AMI-I (GCT) or the above therapy plus P (GP). Complete Doppler echocardiography (systolic and diastolic parameters), DI, and systolic blood pressure (SBP) were measured on the 8.07 +/- 1.16(SD) post-infarct day. The same examination was performed to COG. The DI was significantly lower in healthy patients(0.45 +/- 0.23)compared with the value in patients of either GP(0.56 +/- 0.03; P = 0.023)or GCT(0.78 +/- 0.05; P = 0.000). Moreover DI was higher in patients of GCT compared with that of GP(P = 0.000). In addition, perindopril administration decreased isovolumic relaxation time(IRT; 120.00 +/- 4.23 vs. 139.00 +/- 6.74; P = 0.006)and increased significantly ejection time (ET;274.25 +/- 7.35 vs. 253.50 +/- 7.68; P = 0.042). SBP in patients of GP was similar to that of GCT(120.5 +/- 2.85 mmHg vs. 112.5 +/- 3.49 mmHg; P = NS).

CONCLUSIONS

Global LV function (DI) is impaired in patients with AMI-I. Administration of perindopril has a favorable impact on LV performance in patients with AMI-I, achieved through improvement of the diastolic function (IRT), which indirectly improves LV systolic function (ET, DI). This beneficial influence of perindopril is the result of the direct tissue effect of the drug and not its hemodynamic action.

Approaches to statistical analysis of repeated echocardiographic measurements after myocardial infarction and its relation to heart failure: Application of a random-effects model

BACKGROUND

Extensive left ventricular (LV) dilatation after myocardial infarction (MI) is associated with increased heart failure risk.

AIMS

To investigate whether the power to demonstrate the relation between LV dilatation and heart failure depends on the method applied to predict LV dilatation after MI.

METHODS

A random-effects model and ANOVA model for repeated measurements (MANOVA) were applied to predict LV volume index during 1 year for 298 post-MI patients. Spearman correlation coefficients (r) were calculated and Cox regression analysis was used to calculate risk ratio's (RR).

RESULTS

LV volume indices were more accurately predicted by a random-effects model than by a MANOVA model (systolic/diastolic respectively r = 0.93/0.91 vs. r = 0.67/0.64). Furthermore, patients with high LV volume index as predicted by the random-effects model, had significantly increased heart failure risk (systolic RR 2.04 (95% CI: 1.31 to 3.17; P = 0.001), diastolic RR 1.80 (95% CI: 1.16 to 2.78; P = 0.007). Using the same data, MANOVA failed to demonstrate this relation significantly (systolic RR 1.77 (95% CI: 0.79 to 3.98; P = 0.16), diastolic RR 1.49 (95% CI: 0.68 to 3.30; P = 0.31).

CONCLUSION

When analyzing repeated measurement data, random-effect models are more powerful in detecting clinical relations than are MANOVA models, especially in the presence of missing values.

Improved survival with simendan after experimental myocardial infarction in rats

This study compared the effects of simendan, a calcium sensitizer, with those of milrinone and enalapril on survival of rats with healed myocardial infarction. Seven days after ligation-induced myocardial infarction, the rats were randomized to control, milrinone, enalapril, or simendan groups. All compounds were administered via the drinking water for 312 days, at which time there was 80% mortality in the control group--the study's primary endpoint. The infarct sizes were similar across all groups. At endpoint, the mortality rates were: 63% (milrinone), 56% (enalapril) and 53% (simendan); the risk reductions were 25% (P = 0.04 vs. control) and 28% (P = 0.02 vs. control) with enalapril and simendan, respectively. Milrinone had no statistically significant effect on the survival rate. These findings suggest that, like enalapril, simendan improved survival in rats with healed myocardial infarction.

Beneficial effects of ramipril on left ventricular end-diastolic and end-systolic volume indexes after uncomplicated invasive revascularization are associated with a reduction in cardiac events in patients with moderately impaired left ventricular function and no clinical heart failure

OBJECTIVES We sought to assess the effect of ramipril on left ventricular (LV) volumes, and the clinical significance thereof, in patients with moderate LV dysfunction and no clinical heart failure undergoing invasive revascularization for chronic stable angina.

BACKGROUND

It is unsettled whether treatment with an angiotensin-converting enzyme inhibitor has an impact on LV volumes in this patient group, and, if so, whether this is associated with the clinical outcome.

METHODS

A total of 133 patients with a left ventricular ejection fraction (LVEF) between 0.30 and 0.50 and no clinical heart failure undergoing invasive revascularization for chronic stable angina were randomized to receive ramipril 10 mg once daily or placebo and were followed for a median of 33 months with echocardiography at baseline and 3, 12 and 24 months postoperatively.

RESULTS

Repeated measures analysis of all time points showed that ramipril significantly reduced the end-diastolic volume index (EDVI) (p = 0.032) and end-systolic volume index (ESVI) (p = 0.006) as compared with placebo. Ramipril also reduced the incidence of the triple composite end point of cardiac death, acute myocardial infarction or development of heart failure (p = 0.046). Cox regression analysis, controlling for baseline LVEF and assignment to ramipril, revealed: 1) that increases in EDVI and ESVI up to three months predicted an increasing risk of a future adverse clinical outcome; and 2) that the benefit with ramipril on clinical outcome was partly dependent on a reduction in LV volumes.

CONCLUSIONS

Even in this patient group, LV dilation may supervene and lead to an adverse clinical outcome. Ramipril reduces the postoperative increase in LV volumes and may thereby improve clinical outcome.

How long should angiotensin-converting enzyme inhibitors be given to patients following myocardial infarction: implications of the HOPE trial

Long-term treatment with angiotensin-converting enzyme inhibitors reduces post-infarction morbidity and mortality in patients with left ventricular (LV) systolic dysfunction or symptomatic heart failure. Until recently, the effect of such treatment in patients with preserved LV function has not been known. The results from the Heart Outcome Prevention Evaluation trial have indicated that long-term treatment with ramipril leads to a significant reduction in cardiovascular events in patients with atherosclerotic disease, including those with prior myocardial infarction and preserved LV function. These results suggest that long-term angiotensin-converting enzyme inhibition should also be considered in post-infarction patients with normal cardiac function.

Comparison of methods of fractional area change for detection of regional left ventricular dysfunction

Three methods for assessment of fractional area change (FAC) and conventional versus cross-sectional segmentation were compared under conditions known to occur frequently during stress echocardiography. Quantitative analysis of 80 echocardiograms obtained from healthy subjects, patients with left ventricular (LV) dysfunction and after coronary artery bypass grafting included segmental and cross-sectional FACs by the centroid method with fixed and floating reference and a method with floating external reference. All segmental and cross-sectional FACs were equally sensitive to LV dysfunction, and segmental FACs failed to accurately predict the location of coronary lesions. The centroid method with floating reference and cross-sectional FACs were the least affected by surgery induced intrathoracic heart motion. In moderate to severe LV dysfunction FAC by the centroid method with floating reference and cross sections were rarely within normal limits. Cross-sectional FACs may prove to be useful in stress echocardiography. For viability studies segmental FAC by fixed reference appears to be the method of choice.

Echocardiographic predictors of clinical outcome in patients with left ventricular dysfunction enrolled in the SOLVD registry and trials: significance of left ventricular hypertrophy. Studies of Left Ventricular Dysfunction

OBJECTIVES

To assess the relation of left ventricular (LV) and left atrial (LA) dimensions, ejection fraction (EF) and LV mass to subsequent clinical outcome of patients with LV dysfunction enrolled in the Studies of Left Ventricular Dysfunction (SOLVD) Registry and Trials.

BACKGROUND

Data are lacking on the relation of LV mass to prognosis in patients with LV dysfunction and on the interaction of LV mass with other measurements of LV size and function as they relate to clinical outcome.

METHODS

A cohort of 1,172 patients enrolled in the SOLVD Trials (n = 577) and Registry (n = 595) had baseline echocardiographic measurements and follow-up for 1 year.

RESULTS

After adjusting for age, New York Heart Association (NYHA) functional class, Trial vs. Registry and ischemic etiology, a 1-SD difference in EF was inversely associated with an increased risk of death (risk ratio, 1.62; p = 0.0008) and cardiovascular (CV) hospitalization (risk ratio, 1.59; p = 0.0001). Consequently, the other echo parameters were adjusted for EF in addition to age, NYHA functional class, Trial vs. Registry and ischemic etiology. A 1-SD difference in LV mass was associated with increased risk of death (risk ratio of 1.3, p = 0.012) and CV hospitalization (risk ratio of 1.17, p = 0.018). Similar results were observed with the LA dimension (mortality risk ratio, 1.32; p < 0.02; CV hospitalizations risk ratio, 1.18; p < 0.04). Likewise, LV mass > or =298 g and LA dimension > or =4.17 cm were associated with increased risk of death and CV hospitalization. An end-systolic dimension >5.0 cm was associated with increased mortality only. A protective effect of EF was noted in patients with LV mass > or =298 g (those in the group with EF >35% had lower mortality) but not in the group with LV mass <298 g.

CONCLUSIONS

In patients with LV dysfunction enrolled in the SOLVD Registry and Trials, increasing levels of hypertrophy are associated with adverse events. A protective effect of EF was noted in patients with LV mass > or =298 g (those in the group with EF >35% fared better) but not in the group with LV mass <298 g. These data support the development and use of drugs that can inhibit hypertrophy or alter its characteristics.

Myocardial infarction and left ventricular remodeling: results of the CEDIM trial. Carnitine Ecocardiografia Digitalizzata Infarto Miocardico

Left ventricular dilatation after acute myocardial infarction (MI) is a powerful predictor of progressive functional deterioration, culminating in heart failure and death. The most important determinants of post-MI left ventricular remodeling are the size of the infarct, the degree of residual stenosis in the infarct-related artery, and the viability of the infarct zone. In addition to reperfusion therapy and angiotensin-converting enzyme inhibition, metabolic intervention with L-carnitine may represent a therapeutic approach for preventing left ventricular dilatation and preserving cardiac function. Ongoing studies with early metabolic intervention with carnitine in the acute phase of infarction may prove successful in protecting the microcirculation against ischemic damage and enhancing its ability to respond to blood flow resumption. The results of the multicenter, randomized, double-blind Carnitine Ecocardiografia Digitalizzata Infarto Miocardico (CEDIM) trial suggest that the early and long-term administration of L-carnitine attenuates progressive left ventricular dilatation after acute anterior MI. Results show significant, consistent reductions in end-diastolic volume and end-systolic volume in patients who received L-carnitine compared with placebo. The ongoing CEDIM-2 trial (projected 4000 patients with acute MI) will assess the efficacy of L-carnitine in reducing the combined incidence of death and heart failure at 6 months. In addition to standard reperfusion therapy and angiotensin-converting enzyme inhibition, metabolic intervention with L-carnitine may be a therapeutic approach for preventing left ventricular dilatation and preserving cardiac function by limiting infarct size, decreasing residual stenosis in the infarct-related artery, and increasing viability of the infarct zone.

The Angiotensin Converting Enzyme Inhibition Post Revascularization Study (APRES). Effects of ramipril in patients with reduced left ventricular function. Rationale, design, methods, baseline characteristics and first-year experience

Invasive revascularization improves prognosis, functional status and quality of life in patients with severe angina pectoris and impaired left ventricular function, and treatment with ACE-I reduces the development of cardiac events and left ventricular dysfunction in patients without or with mild angina pectoris. However, the effects of a combined treatment strategy with invasive revascularization and subsequent long-term ACE-I therapy in patients with limiting angina pectoris and impaired left ventricular function have not previously been investigated. APRES is a long-term, prospective, randomized double-blind study that evaluates the effects of ramipril 10 mg o.d. on the long-term development of cardiac events, left ventricular function, functional status and quality of life following invasive revascularization in patients without recent AMI or clinical heart failure and with preoperative ejection fraction in the range 0.30-0.50. The rationale, design and power of APRES and the choice and relevance of outcome measures are discussed. Based on experience and results from the first year of the study for screening procedure, inclusion rate, patient compliance, reproducibility analyses and the magnitude of outcome measures, we conclude that the study is feasible and safe. The included patients match with the target population, the outcome measures seem appropriate and the power considerations valid for the majority of the outcome measures.

New concept in echocardiography: harmonic imaging of tissue without use of contrast agent

BACKGROUND

Endocardial border detection is important for echocardiographic assessment of left-ventricular function. Second harmonic imaging of contrast agents enhances this border detection. We discovered that harmonic imaging improves tissue visualisation even before contrast injection. We therefore sought objectively to demonstrate the degree of enhancement of endocardial and myocardial visualisation.

METHODS

An ATL HDI-3000 scanner with software for contrast harmonic imaging was used to record short-axis images of the left ventricle in 27 patients with possible myocardial disease and 22 controls, in the fundamental mode and with harmonic imaging. A computer program measured the relative grey-scale values within six segments of the endocardium and myocardium. An Acuson Sequoia scanner equipped with software for tissue harmonic imaging was used to investigate the reproducibility of ejection-fraction calculations in 22 patients with ischaemic heart disease.

FINDINGS

Harmonic imaging produced brighter endocardium within each segment. Relative to the mean grey value of the total imaging sector, the values for harmonic and fundamental imaging were 171.5 vs 85.6% (p<0.0001) in end diastole and 194.1 vs 106.7% (p<0.0001) in end systole. Results for the myocardial segments were also significantly better for harmonic imaging. Structure enhancement of similar magnitude was seen among patients and healthy controls. Use of harmonic imaging reduced the proportion of unacceptable images by 14-46% in different views and improved the reproducibility of biplane ejection-fraction measurements.

INTERPRETATION

In comparison with fundamental imaging, the relative endocardial and myocardial brightness is enhanced by harmonic imaging.

Left ventricular dilatation after myocardial infarction: ACE inhibitors, beta-blockers, or both?

Left ventricular (LV) dilatation after myocardial infarction (MI) is a major predictor of prognosis and identifies which patients will develop heart failure. Left ventricular dilatation or remodeling starts immediately after MI and progresses in the chronic phase of heart failure. Factors influencing remodeling, such as infarct size and neurohumoral activation, including the sympathetic and renin-angiotensin system, are discussed. Remodeling can be affected by reduction of infarct size and inhibition of neurohumoral activation. The effect of thrombolysis, beta-blockade, and angiotensin-converting enzyme (ACE) inhibition in the acute phase after MI and in the chronic phase of heart failure on remodeling are discussed. On the basis of beneficial effects of ACE inhibition and beta-blockade in acute MI and in chronic heart failure, a treatment strategy is proposed in which both ACE inhibition and beta-blockade are started early after MI. Depending on infarct size and ventricular function, continued treatment in the chronic phase of heart failure must be considered.

Echocardiography to understand remodeling and to assess prognosis after acute myocardial infarction

Ventricular remodeling indicates a dynamic process, starting with and after acute myocardial infarction, as a result of structural and functional modifications which involve acutely and chronically both the infarcted and noninfarcted zones of the left ventricle. The most effective way to prevent or minimize post-MI cardiac remodeling is to limit the extent of the initial insult. This can be partly achieved by early myocardial reperfusion obtained by different strategies including thrombolysis. In 6405 patients of the GISSI-3 trial, 2D echocardiographic studies were available at predischarge, at 6 weeks and at 6 months after the infarction. The increase in left ventricular volumes over time was reduced by 6-week lisinopril treatment. Patients randomized to lisinopril had smaller volume also at 6 months, after withdrawal of treatment at 6 weeks. Important prognostic indications can also be derived from predischarge echocardiography, since larger quartiles of left ventricular volumes and lower quartile of ejection fraction indicates higher risk of mortality and non-fatal congestive heart failure in the 6 months after the index event, even in the relatively low risk general population of infarcts of the GISSI-3.

Effects of stenting of recent or chronic coronary occlusions on late vessel patency and left ventricular function

Due to high rates of late vessel reocclusion, balloon angioplasty of recent or chronic coronary occlusions is not associated with a sustained improvement in left ventricular function. Recent studies have suggested that stent implantation at coronary occlusions significantly reduces late vessel occlusion. We thus designed a study to analyze the effect of stent implantation at coronary occlusions on late vessel potency and left ventricular function. Twenty-four consecutive patients with recent or chronic coronary occlusions had successful stent implantation and were enrolled in a 6-month angiographic follow-up program. Contrast left ventricular cineangiography, at baseline and 6-month follow-up, as well as preprocedural, postprocedural, and follow-up angiograms analyzed with quantitative angiography were available in 22 of the patients (92%). At follow-up, no vessel reocclusion was observed and 32% of the patients, as analyzed by the >50% diameter stenosis criterion, had restenosis. There was a significant improvement in global left ventricular function with a decrease in both left ventricular end-diastolic volume index (LVEDVI, p <0.01) and left ventricular end-systolic volume index (LVESVI, p <0.0001) and an increase in left ventricular ejection fraction (LVEF, p <0.0001). Similarly, regional wall motion in the territory of the recanalized artery was also significantly improved (p <0.05). These effects were associated with a reduction in left ventricular filling pressure (p <0.0001). Stent implantation following balloon angioplasty of recent or chronic coronary occlusion is associated with a low rate of late vessel reocclusion, a reduction in cardiac volume, and an increase in ejection fraction. Such effects on left ventricular volumes could have a significant impact on patient survival.

Effects of enalapril on left ventricular function and exercise performance after a first acute myocardial infarction. The EDEN Study Investigators

AIMS

To study the effects of early use of enalapril on left ventricular function and exercise capacity after a first acute myocardial infarction, 356 patients without overt signs of congestive heart failure were randomly allocated to receive placebo or enalapril between days 7 and 14 after a first myocardial infarction. The study was conducted double-blind in 40 hospitals throughout Spain.

METHODS AND RESULTS

At baseline and after 26 weeks of follow-up exercise stress tests, Doppler-echocardiograms and isotopic ventriculography were performed in study participants. At the end of follow-up, patients in the enalapril group had lower end-systolic volume compared to those in the placebo group (55 vs. 62 ml; P=0.05). No difference in exercise capacity was evident between both groups.

CONCLUSION

The present study shows that enalapril therapy administered between 7 and 14 days after a first acute myocardial infarction decreases end-systolic volume and may inhibit the remodeling process of the left ventricle.

Hemodynamic effects of anesthesia in patients with ischemic heart failure chronically treated with angiotensin-converting enzyme inhibitors

Anesthesia may induce hemodynamic instability in patients treated with angiotensin-converting enzyme inhibitors (ACEIs). To assess the hemodynamic effects of anesthesia in patients treated (n = 9) or not treated (n = 9) with ACEIs for ischemic left ventricle dysfunction after myocardial infarction, we studied 18 patients scheduled for elective coronary artery bypass graft surgery. Induction of anesthesia with fentanyl (5 micrograms/kg), flunitrazepam (30 micrograms/kg), and pancuronium (100 micrograms/kg) was followed by a significant decrease in mean arterial blood pressure in both groups (-18.6% +/- 8.1% in controls and -25.7% +/- 7.8% in ACEI-treated patients, P = 0.01). In controls, cardiac index and systemic vascular resistance were not significantly altered (-11.2% +/- 9.4% and -16.2% +/- 4.6%, respectively, not significant [NS]). In ACEI-treated patients, cardiac index decreased significantly (-27.3% +/- 11.6%, P = 0.01 from baseline and P = 0.03 when compared with controls), and systemic vascular resistance was unchanged (1.0% +/- 18.7%, NS from baseline and P = 0.04 when compared with controls). Two patients from each group experienced a transient severe hypotensive episode. ACEI treatment in patients with infarction-induced myocardial dysfunction does not increase the incidence of severe hypotension after induction of anesthesia.

What is the role of angiotensin-converting enzyme inhibitors in congestive heart failure and after myocardial infarction?

OBJECTIVE

To discuss the controversies surrounding the choice of angiotensin-converting enzyme (ACE) inhibitor, and the timing, dosage, and duration of ACE inhibitor therapy for congestive heart failure (CHF) and after myocardial infarction (MI). The beneficial effects of ACE inhibition in patients with CHF and after MI are reviewed. Human clinical trials are reviewed and their clinical implications are discussed.

DATA SOURCES

MEDLINE searches (1985-1995) identified human clinical trials and review articles.

DATA EXTRACTION

Landmark human clinical trials with morbidity and mortality end points were included. The validity of the study data were assessed on the basis of study methods, population characteristics, and statistical power.

DATA SYNTHESIS

ACE inhibitors exert beneficial effects in patients with CHF by hemodynamic and neurohormonal mechanisms. The attenuation of ventricular remodeling that occurs with ACE inhibition does not fully explain the results of clinical trials in patients after MI. Routine determination of ejection fraction to guide ACE inhibitor therapy is not as important as the patient's clinical status. Clinicians should titrate the chosen ACE inhibitor on the basis of hemodynamic response to target doses used in major clinical trials. Because the beneficial effects of ACE inhibitors appear to be a class effect, choice of an agent should include cost considerations and the results of clinical trials.

CONCLUSIONS

ACE inhibitor reduce morbidity and mortality in selected CHF and post-MI patients. Patients with symptomatic CHF benefit most from ACE inhibitor therapy, and it should be continued indefinitely. Treatment effects in asymptomatic patients are delayed. The role of ACE inhibitor therapy in preventing morbidity and morality in asymptomatic patients with preserved ventricular function requires further study.

Benefit of converting enzyme inhibition on left ventricular volumes and ejection fraction in patients receiving beta-blockade after myocardial infarction. CONSENSUS II multiecho study group

Beta-blockers reduce infarct size and improve survival after acute myocardial infarction (MI). Post-MI angiotensin-converting enzyme inhibition also improves survival and may attenuate left ventricular (LV) dilatation. We evaluated the effect of early enalapril treatment on LV volumes and ejection fraction (EF) in patients on concomitant beta-blockade after MI. Intravenous enalaprilat or placebo was administered <24 hours after MI and was continued orally for 6 months. LV volumes were assessed by echocardiography 3 +/- 2 days, 1 and 6 months after MI. Change in LV diastolic volume during the first month was attenuated with enalapril (2.7 vs placebo 6.5 ml/m2 change; p < 0.05), and significantly lower LV diastolic and systolic volumes were observed with enalapril treatment compared with placebo at 1 month (enalapril 47.21 23.9 vs placebo 53.1/29.2 ml/m2; p < 0.05) and at 6 months (enalapril 47.9/24.8 vs placebo 53.8/29.6 ml/m2; p < 0.05). EF was also significantly higher 1 month after MI in these patients (enalapril 50.4% vs placebo 46.4%; p < 0.05). Our date demonstrate that early enalapril treatment attenuates LV volume expansion and maintains lower LV volumes and higher EF in patients receiving concurrent beta-blockade after MI. A possible additive effect of combined therapy should be evaluated prospectively.

Effect of enalapril initiated early after acute myocardial infarction on heart failure parameters, with reference to clinical class and echocardiographic determinants. CONSENSUS II Multi-Echo Study Group

BACKGROUND AND HYPOTHESIS

Although the angiotensin-converting enzyme inhibitor enalapril has recently been shown to reduce mortality and the need for hospitalization in patients with left ventricular dysfunction and congestive heart failure, this drug was found to have no significant impact on short-term mortality after acute myocardial infarction (AMI) in the CONSENSUS II trial. The effect of enalapril initiated early after AMI on clinical and echocardiographic determinants of left ventricular (LV) function was studied in a subset of patients from CONSENSUS II.

METHODS

Symptoms and signs of heart failure were classified as NYHA and dyspnea classes. Echocardiography included LV end-systolic volumes (ESV) and end-diastolic volumes (EDV), as well as ejection fraction (EF), wall motion index (WMI), and mitral flow indices. In all, 428 patients were included and followed for an average of 5.1 months by serial examinations, starting 2-5 days after myocardial infarction (MI) and repeated after 1 month and at the completion of the study.

RESULTS

There was no beneficial effect of enalapril on clinically determined function. Changes (i.e., changes in NYHA class) in the functional status remained correlated with changes in echocardiographic determinants throughout the study in patients belonging to the placebo group: EDV index (r = 0.36, p = 0.002, ESV index (r = 0.49, p < 0.001), EF (r = -0.41, p < 0.001), and WMI (r = 0.29, p = 0.008). In a stepwise logistic regression model, the best baseline parameters to predict NYHA class at final visit in all patients were age (p = 0.014) and ESV index (p = 0.001).

CONCLUSION

Enalapril treatment for an average period of 5.1 months following MI resulted in no clinically significant beneficial effects on NYHA and dyspnea class. Changes in clinical function class were correlated with changes in echocardiographic determinants in placebo-treated patients, but not in patients given enalapril.

Plasma brain natriuretic peptide as an indicator of left ventricular systolic function and long-term survival after acute myocardial infarction. Comparison with plasma atrial natriuretic peptide and N-terminal proatrial natriuretic peptide

BACKGROUND

Elevated plasma levels of atrial natriuretic peptide (ANP) and the N-terminal fragment of the ANP prohormone (N-ANP) are associated with decreased left ventricular function and decreased long-term survival after acute myocardial infarction (AMI). Previous data suggest that plasma brain natriuretic peptide (BNP) may increase proportionally more than plasma ANP after AMI and in chronic heart failure. The diagnostic and prognostic value of plasma BNP as an indicator of left ventricular dysfunction and long-term survival after AMI, relative to that of ANP and N-ANP, remain to be established.

METHODS AND RESULTS

Venous blood samples for analysis of ANP, N-ANP, and BNP were obtained on day 3 after symptom onset from 131 patients with documented AMI. Left ventricular ejection fraction was determined by echocardiography in a subsample of 79 patients. Twenty-eight cardiovascular and 3 noncardiovascular deaths occurred during the follow-up period (median, 1293 days). All three peptides proved to be powerful predictors of cardiovascular mortality by univariate Cox proportional hazards regression analyses (ANP: P < .0001; N-ANP: P = .0002; BNP: P < .0001). In a multivariate model, plasma BNP (P = .021) but not ANP (P = .638) or N-ANP (P = .782) provided additional prognostic information beyond left ventricular ejection fraction. Logistic regression analysis showed that ANP (P = .003) and N-ANP (P = .027) but not BNP (P = .14) were significantly associated with a left ventricular ejection fraction < or = 45%.

CONCLUSIONS

These results suggest that plasma BNP determination provides important, independent prognostic information after AMI. Although plasma ANP appears to be a better predictor of left ventricular dysfunction, plasma BNP may have greater potential to complement standard prognostic indicators used in risk stratification after AMI because of its strong, independent association with long-term survival, enhanced in vitro stability, and simplicity of analysis.

Effect of early enalapril therapy on left ventricular function and structure in acute myocardial infarction

Infarct expansion starts within hours to days after transmural myocardial injury. Previous echocardiographic and left ventriculographic studies demonstrated that angiotensin-converting enzyme (ACE) inhibitor therapy limits left ventricular dilatation, particularly in patients with anterior wall acute myocardial infarction (AMI) or impaired left ventricular function. Forty-three patients with an acute Q-wave AMI were randomized within 24 hours of symptom onset to intravenous enalaprilat (1 mg) or placebo. Patients were then given corresponding oral therapy and followed for 1 month. Predrug and 1-month gated blood pool scans were obtained in 32 patients to evaluate changes in cardiac volumes and ejection fraction. Twenty-three patients underwent magnetic resonance imaging at 1 month to evaluate left ventricular infarct expansion. Blood pressure decreased at 6 hours but returned to baseline in both groups after 1 month of therapy. The change in cardiac volumes from baseline to 1 month differed between the placebo (end-diastolic volume +16 +/- 5 ml, end-systolic volume +8 +/- 6 ml), and enalapril (end-diastolic volume -8 +/- 9 ml and end-systolic volume -14 +/- 7 ml) groups (p < 0.05 vs placebo). Global and infarct zone ejection fractions improved significantly at 1 month in the enalapril group (+6 +/- 3% and 19 +/- 5%, respectively) but did not change over 1 month in the placebo group. Infarct segment length and infarct expansion index by magnetic resonance imaging were significantly less in those treated with enalapril, suggesting less infarct expansion in this group. Thus, early administration of enalaprilat to patients presenting with a first Q-wave AMI prevents cardiac dilatation and infarct expansion.

Neurohumoral measurements as indicators of long-term prognosis after acute myocardial infarction

The objective of this study was to evaluate the prognostic accuracy and usefulness of neurohumoral determination as a risk stratification tool after acute myocardial infarction (AMI) by comparing the long-term prognostic value of subacute neurohumoral measurements with other established indicators of adverse outcome. The study included 145 patients with documented AMI. During a median follow-up of 3.7 years, 30 cardiovascular and 6 noncardiovascular deaths occurred. By univariate analysis, plasma atrial natriuretic factor (ANF) and endothelin levels were strongly related to long-term cardiovascular mortality. In multivariate models, both peptides added prognostic information to that obtained from clinical evaluation, but not to that obtained from left ventricular ejection fraction (LVEF). Estimation of the area under the receiver-operating characteristic curve showed comparable prognostic accuracy for LVEF (0.7788), plasma ANF (0.7795), plasma endothelin (0.7493), and Killip classification (0.8203), meaning that for all these prognostic indicators, a randomly selected patient from the group of patients dying will have a test value larger than that of a randomly selected patient from the group of surviving patients 75% to 82% of the time. The clinical usefulness of neurohumoral determination in routine risk stratification after AMI appears to be limited since no additional prognostic information to that provided by objective evaluation of LV systolic function is obtained. However, in patients for whom objective assessment of LV performance is not readily available, measurement of plasma ANF and endothelin may be helpful in identifying asymptomatic patients at risk for cardiac death.

Effects of L-carnitine administration on left ventricular remodeling after acute anterior myocardial infarction: the L-Carnitine Ecocardiografia Digitalizzata Infarto Miocardico (CEDIM) Trial

OBJECTIVES

This study was performed to evaluate the effects of L-carnitine administration on long-term left ventricular dilation in patients with acute anterior myocardial infarction.

BACKGROUND

Carnitine is a physiologic compound that performs an essential role in myocardial energy production at the mitochondrial level. Myocardial carnitine deprivation occurs during ischemia, acute myocardial infarction and cardiac failure. Experimental studies have suggested that exogenous carnitine administration during these events has a beneficial effect on function.

METHODS

The L-Carnitine Ecocardiografia Digitalizzata Infarto Miocardico (CEDIM) trial was a randomized, double-blind, placebo-controlled, multicenter trial in which 472 patients with a first acute myocardial infarction and high quality two-dimensional echocardiograms received either placebo (239 patients) or L-carnitine (233 patients) within 24 h of onset of chest pain. Placebo or L-carnitine was given at a dose of 9 g/day intravenously for the first 5 days and then 6 g/day orally for the next 12 months. Left ventricular volumes and ejection fraction were evaluated on admission, at discharge from hospital and at 3, 6 and 12 months after acute myocardial infarction.

RESULTS

A significant attenuation of left ventricular dilation in the first year after acute myocardial infarction was observed in patients treated with L-carnitine compared with those receiving placebo. The percent increase in both end-diastolic and end-systolic volumes from admission to 3-, 6- and 12-month evaluation was significantly reduced in the L-carnitine group. No significant differences were observed in left ventricular ejection fraction changes over time in the two groups. Although not designed to demonstrate differences in clinical end points, the combined incidence of death and congestive heart failure after discharge was 14 (6%) in the L-carnitine treatment group versus 23 (9.6%) in the placebo group (p = NS). Incidence of ischemic events during follow-up was similar in the two groups of patients.

CONCLUSIONS

L-Carnitine treatment initiated early after acute myocardial infarction and continued for 12 months can attenuate left ventricular dilation during the first year after an acute myocardial infarction, resulting in smaller left ventricular volumes at 3, 6 and 12 months after the emergent event.

Effects of early enalapril treatment on global and regional wall motion in acute myocardial infarction. CONSENSUS II Multi Echo Study Group

Angiotensin-converting-enzyme inhibitor therapy can preserve left ventricular (LV) function and geometric features and improve survival in subsets of patients with acute myocardial infarction (AMI). We investigated the effect of enalapril treatment initiated < 24 hours after AMI on global and regional echocardiographic wall motion indexes obtained at 2 to 5 days and at 1 and 6 months in 428 consecutive patients enrolled in the randomized, placebo-controlled Cooperative New Scandinavian Enalapril Survival Study II. In anterior AMIs, the non-infarct-zone index deteriorated in the placebo group but remained unchanged in the enalapril-treated group (0.18 vs 0.02; p < or = 0.05), an effect related to attenuated LV volume expansion. No treatment effects were observed in nonanterior AMIs or in the entire unselected population. Thus in an unselected population with AMI, early enalapril treatment had no effect on LV function; yet in patients with anterior infarcts, LV function was maintained through preservation of function in the noninfarcted myocardium.

Left ventricular volumes, ejection fraction, and plasma proatrial natriuretic factor (1-98) after withdrawal of enalapril treatment initiated early after myocardial infarction. CONSENSUS II Multi-Echo Study Group

OBJECTIVES

To assess whether the reduction in left ventricular dilatation after acute myocardial infarction obtained by early administration of angiotensin converting enzyme inhibitors depends on continuous treatment.

DESIGN

Prospective observational and cross sectional study of withdrawal of randomised treatment with enalapril or placebo.

PATIENTS

106 patients on 6 months trial treatment after an acute myocardial infarction.

MAIN OUTCOME MEASURES

Left ventricular volumes and ejection fraction as assessed by echocardiography and circulating proatrial natriuretic factor (1-98) before and 4-6 weeks after withdrawal of treatment.

RESULTS

There were no significant changes (mean (SD)) in left ventricular systolic (0.7 (4.7) ml/m2) and diastolic (0.4 (6.6) ml/m2) volume indices, ejection fraction (-0.9 (6)%), and proatrial natriuretic factor (172 (992) pmol/l) after withdrawal of enalapril. The significantly lower left ventricular volumes observed with 6 months of enalapril therapy after acute myocardial infarction, as compared with placebo, were maintained 6 weeks after drug withdrawal.

CONCLUSION

The results show that the benefit of 6 months of enalapril treatment initiated early after myocardial infarction is maintained for at least 6 weeks after drug withdrawal, suggesting that the treatment effect on left ventricular structure is not reversed by changes in loading conditions caused by subsequent drug withdrawal.

Plasma proatrial natriuretic factor (1-98) concentration after myocardial infarction: relation to indices of cardiac and renal function

OBJECTIVES

(a) To assess the relation between plasma concentrations of proatrial natriuretic factor (1-98) and non-invasively derived indices of left ventricular systolic and diastolic performance and (b) to assess the potential confounding effect of renal function and age on this relation in patients with acute myocardial infarction.

DESIGN

Cross sectional comparison of biochemical and echocardiographic indices of cardiac function.

SETTING

Norwegian central hospital.

PATIENTS

Sixty four patients with acute myocardial infarction.

MAIN OUTCOME MEASURES

Relation between plasma proatrial natriuretic factor (1-98) concentrations and echocardiographic indices of left ventricular systolic function as assessed by univariate and multivariate linear regression analysis. Sensitivity and specificity of plasma proatrial natriuretic factor (1-98) concentration as a measure of left ventricular systolic and diastolic dysfunction.

RESULTS

Plasma proatrial natriuretic factor (1-98) concentrations were significantly related to left ventricular ejection fraction (r = -0.33; P = 0.008), age (r = 0.43; P < 0.001), and creatinine clearance (r = - 0.53; P < 0.001). In a multivariate model left ventricular ejection fraction and creatinine clearance were both independently related to plasma values. The mean concentration of proatrial natriuretic factor (1-98) was significantly higher in patients with an ejection fraction of < 40% than in those with an ejection fraction of > or = 40% (1876 (1151) v 1174 (530) pmol/l; P = 0.03) and in patients with an abnormal transmitral E/A ratio ( < 0.65 or > 1.65, where E/A is ratio of peak early filling velocity to peak atrial component) compared with those with a normal ratio (1572 (895) v 1137 (523) pmol/l, respectively; P = 0.02). When patients were subdivided according to the median concentration of proatrial natriuretic factor (1192 pmol/l) the sensitivity and specificity were 89% and 56% respectively for detecting a left ventricular ejection fraction of < 40% and 75% and 61% respectively for detecting an abnormal E/A ratio. Concentrations below the median had a negative predictive value of 97% in excluding an ejection fraction of < 40% and of 84% in excluding an abnormal E/A ratio.

CONCLUSION

These results suggest that soon after myocardial infarction left ventricular ejection fraction and indices of renal function are independently related to plasma concentrations of proatrial natriuretic factor (1-98). Plasma concentrations of proatrial natriuretic factor (1-98) seem to reflect renal and cardiac performance rather than specific haemodynamic variables assessed by noninvasive methods. Plasma proatrial natriuretic factor (1-98) measurements may be a useful screening tool to identify patients with normal cardiac function soon after myocardial infarction.

Reduction of ischemic events with angiotensin-converting enzyme inhibitors: lessons and controversy emerging from recent clinical trials

Angiotensin-converting enzyme (ACE) inhibitor therapy has been associated with a substantial (> or = 20%) reduction in the risk of major ischemic events in two recent clinical trials with long-term follow-up: Studies of Left Ventricular Dysfunction (SOLVD) and the Survival and Ventricular Enlargement (SAVE) study. Participants in these studies included patients with a low ejection fraction (< or = 0.35 in SOLVD and < or = 0.40 in SAVE), generally without symptoms of congestive heart failure. Approximately 80% of patients enrolled in SOLVD and all participants in SAVE had histories of ischemic heart disease or acute myocardial infarction (SAVE). In both SOLVD and SAVE the risk of experiencing a major ischemic event such as myocardial infarction was reduced significantly following prolonged ACE inhibitor therapy. In the SOLVD trial, this effect was evident across a range of patient subgroups, including varying concomitant drug therapies. In both studies, several months elapsed before this benefit became apparent, suggesting an effect on underlying ischemic pathophysiology. A third trial of ACE inhibitor therapy postinfarction, the Acute Infarction Ramipril Efficacy (AIRE) Study, demonstrated a 27% reduction in all cause mortality but no effect on myocardial infarction after a 15-month mean follow-up. No effect of ACE inhibition on risk of survival or reinfarction was reported in the Cooperative New Scandinavian Enalapril Survival Study (CONSENSUS-II), which began the drug within 24 hours of infarction and terminated follow-up at 6 months, a time not likely to demonstrate infarction reduction benefit based on the SOLVD and SAVE observations. Neither AIRE nor CONSENSUS-II had objectively determined left ventricular dysfunction as an entry criterion, as did SOLVD and SAVE, but AIRE mandated "clinical" congestive heart failure prior to randomization. More recently, preliminary results from the third Gruppo Italiano per lo Studio della Sopravvivenza nell'Infarto Miocardico (GISSI-3), the Fourth International Study of Infarct Survival (ISIS-4), and the Chinese Captopril Trial suggested that angiotensin-converting enzyme (ACE) inhibitor mortality benefits post-myocardial infarction would be detected in these megatrials as early as 35 days after the event.(ABSTRACT TRUNCATED AT 400 WORDS)