Lisinopril in the Treatment of Congestive Heart Failure in Elderly Patients: Comparison versus Captopril

The present study was performed in order to compare the efficacy, safety, and tolerability of lisinopril, a long-acting angiotensin-converting enzyme (ACE) inhibitor, with captopril, the shorter acting ACE inhibitor available, in the treatment of elderly patients (mean age 70 ± 0.5 years) with congestive heart failure (mean left ventricular ejection fraction 33.5 ± 1%). The study was organized according to a double-blind, parallel-group, randomized multicenter protocol. After a 14-day placebo run-in period, patients were randomized to receive either lisinopril 5 mg orally once per day or captopril 12.5 mg orally once per day. The dose of the study drug could be doubled at 2-week intervals for 6 weeks. The maximal dose was lisinopril 20 mg once per day or captopril 25 mg twice per day. The addition of either captopril or lisinopril to a regimen of diuretics caused a significant increase in exercise tolerance assessed by bicycle ergometry after 12 weeks of treatment (530 ± 21 seconds vs. 431 ± 13 seconds, p < 0.01; 555 ± 19 seconds vs. 463 ± 12 seconds, p < 0.01, respectively). Both drugs significantly increased left ventricular ejection fraction and stroke volume, were equally effective in improving NYHA class, and were well tolerated, with no differences detectable between treatments. The results of this study indicate that lisinopril 5–20 mg once daily is at least as effective and well tolerated as captopril 12.5–50 mg daily in the treatment of elderly patients with congestive heart failure.     

Differential effects of captopril and enalapril on tissue renin-angiotensin systems in experimental heart failure.

BACKGROUND. Angiotensin converting enzyme (ACE) inhibitor therapy elicits beneficial responses from patients with heart failure. We hypothesized that a major site of action of these drugs is tissue ACE and that ACE inhibitors might differ in their ability to inhibit tissue ACE. To test this hypothesis, we assessed the effects of captopril and enalapril on blood pressure and renal function and on serum and tissue ACE activities in sham-operated rats and rats with heart failure induced by coronary artery ligation. METHODS AND RESULTS. During short-term (1-week) treatment, captopril (200 mg.kg-1.day-1) and enalapril (25 mg.kg-1.day-1) elicited equipotent effects on blood pressure and inhibition of serum ACE activity (85%). The effects of long-term treatment (47 days) were then studied beginning 45 +/- 5 days after coronary ligation in four treatment groups: sham-operated, vehicle (n = 14); heart failure, vehicle (n = 10); heart failure, captopril (n = 8); and heart failure, enalapril rats (n = 7). During long-term treatment, captopril and enalapril caused comparable falls of 12-18 mm Hg in blood pressure (p < 0.01 compared with vehicle treatment). There was no change in urine volume or sodium or potassium excretion in vehicle- or captopril-treated heart failure rats; in contrast, enalapril-treated heart failure rats demonstrated 83% and 10% increases in urine volume and daily sodium excretion, respectively, compared with vehicle-treated rats (both p < or = 0.01). No significant changes in blood urea nitrogen or creatinine were observed with either treatment. Enalapril but not captopril elicited a significant decrease in serum and lung ACE activities. Captopril but not enalapril inhibited aortic ACE activity. Both agents caused a comparable inhibition of renal ACE activity. The magnitude of inhibition of renal ACE activity but not serum and vascular (aortic) ACE activities correlated with the long-term blood pressure response. Enalapril but not captopril normalized renal angiotensinogen expression; the magnitude of this effect correlated with the increase in daily urinary sodium excretion (r = -0.43; p < or = 0.005). CONCLUSIONS. These data suggest that chronic treatment with these two agents elicits differential effects on tissue ACE activities and renal angiotensinogen regulation. The differential renal effects of these agents may be important in the treatment of heart failure.     

Aspirin Inhibits the Acute Arterial and Venous Vasodilator Response to Captopril in Patients with Chronic Heart Failure

Summary Purpose: The potentially beneficial hemodynamic effects of angiotensin-converting enzyme (ACE) inhibitors in heart failure may relate, in part, to their ability to increase the production of vasodilator prostanoids. Low dose aspirin is commonly prescribed in CHF and may attenuate the vasodilator effects of ACE inhibitors. We sought to determine the effects of low dose aspirin on the peripheral hemodynamic effects of captopril in patients with chronic heart failure (CHF). Methods: Nine patients with chronic heart failure were randomized in a placebo controlled, cross over study, to 75 mg of aspirin daily or placebo. After 7 days treatment the response to 25 mg of captopril was evaluated over 180 min using venous occlusion plethysmography. Forearm blood flow (FBF) and forearm venous capacitance (FVC) were measured. Results: Mean arterial pressure and heart rate did not change. After placebo, FBF increased in response to captopril (+18%, 95%CI 24.2, 11.8), a response inhibited by aspirin (−1.4%, 2.9, −5.7), p < 0.005. After placebo, FVC increased in response to captopril (+7.6%, 9.8, 5.4), which was also inhibited by aspirin (+2.0%, 4.6, −0.6), aspirin vs. placebo, p = 0.02). Conclusion: In patients with chronic heart failure even low dose aspirin inhibits both the acute arterial and venous dilator responses to captopril. This action of aspirin may reduce the long-term clinical benefits of ACE inhibitors     

Placebo-controlled comparison of candoxatril, an orally active neutral endopeptidase inhibitor, and captopril in patients with chronic heart failure

AIMS: To compare the effects on exercise capacity of the neutral endopeptidase inhibitor candoxatril, and the angiotensin converting enzyme inhibitor captopril, in patients with mild to moderate heart failure. METHODS: In this multi-centre double-blind placebo controlled study, 60 patients with NYHA Class I-III heart failure were randomised to candoxatril 200 mg b.d. (n = 22), captopril 25-50 mg b.d. (n = 23) or placebo (n = 15). Treadmill exercise tests were carried out weekly during a 5-week single-blind placebo run-in phase until a stable baseline was achieved, and repeated at 4 weekly intervals during the 12-week double-blind treatment phase. RESULTS: Nine patients withdrew from the study--four candoxatril and five captopril. The placebo-adjusted increase in exercise duration after 12 weeks was 56 s (95% CI, -26 to +137 s; P = 0.12) with candoxatril and 37 s (-43 to + 117 s; P = 0.29) with captopril. CONCLUSIONS: Both candoxatril and captopril were well tolerated and treadmill exercise duration appeared to increase during 12 weeks of therapy but this did not achieve statistical significance. This study tentatively suggests that in patients with heart failure, neutral endopeptidase inhibition may provide similar symptomatic benefits to angiotensin converting enzyme inhibition.     

Cilazapril: an overview of its efficacy and safety in hypertension.

Cilazapril is a new once-daily angiotensin-converting (ACE) enzyme inhibitor which has been administered to 4,500 patients with mainly mild to moderate essential hypertension in a multinational clinical research program. Sitting diastolic blood pressure was reduced by about 9 mm Hg from baseline (p less than 0.01) after 4 weeks of treatment with cilazapril 1.25-10 mg/day in double-blind placebo-controlled studies. Total responder rates to cilazapril were usually 50-60% compared with 30% to placebo. Adding hydrochlorothiazide 12.5 mg/day to cilazapril 5.0 mg/day increased the total responder rate from 52 to 71%. Double-blind dose titration studies for 8 weeks showed that cilazapril 2.5-5 mg/day possessed equivalent efficacy to usual therapeutic regimens of sustained release propranolol, captopril, hydrochlorothiazide, atenolol and enalapril, Cilazapril did not affect heart rate. During long-term open administration for 52 weeks, or longer, cilazapril, either alone or in combination with hydrochlorothiazide, effectively maintained control of blood pressure. Treatment of patients with severe hypertension with cilazapril plus hydrochlorothiazide achieved a total responder rate of 73%. Adverse events were mostly observed within the first 8-16 weeks of treatment, with headache, dizziness, fatigue, nausea, cough and chest pain being the most frequent. Non-life-threatening angioedema, facial edema and mild hypotension occurred in less than or equal to 0.2% of patients, and orthostatic hypotension was reported in 2%. Abnormal laboratory test values were rarely found with cilazapril treatment. Of the 2.3% of patients with elevated serum creatinine, at any time point during the study and irrespective of outcome on continuation with cilazapril therapy, about two thirds had prior renal impairment.(ABSTRACT TRUNCATED AT 250 WORDS)     

Effect of isosorbide-5-mononitrate on exercise performance and clinical status in patients with congestive heart failure. Results of the Nitrates in Congestive Heart Failure (NICE) Study.

BACKGROUND AND AIMS: Nitrate therapy improves hemodynamics in patients with heart failure, but the chronic effects of oral nitrates on exercise performance and clinical status have not been well studied. METHODS: Oral isosorbide-5-mononitrate (ISMN) (50 mg once daily) or placebo was administered to 136 patients (NYHA Class 2-3) treated for heart failure, all receiving captopril and most also furosemide. Endpoints were treadmill exercise time at 12 weeks by modified Naughton protocol (primary), with an additional 12-week follow-up period. Secondary endpoints included left ventricular dimensions, ejection fraction, cardiothoracic ratio, functional class, quality of life, hospitalizations and plasma norepinephrine and atrial natriuretic peptide in a four-center substudy. RESULTS: Intention-to-treat analysis showed that mean change in treadmill exercise duration tended to be greater in patients receiving ISMN than placebo (treatment difference +42 s, 95% CI -5, +90 s at 12 weeks and +21 s, 95% CI -25, +74 s after 24 weeks) (NS). Treatment difference was greater in the prespecified subgroup with ejection fraction 31-40% (+55 s, 95% CI -11, +136 s at 12 weeks and +65 s, 95% CI +3, +147 s) (p = 0.035) at 24 weeks. No deleterious effects (i.e. hypotension) were observed with ISMN, although headache was reported in 19% of the active treatment group (p = 0.0001). CONCLUSIONS: ISMN added to captopril increased treadmill exercise time in patients with heart failure and a lesser reduction in baseline ejection fraction, although for the group as a whole, the increase in treadmill time was not significant.     

Assessment of quality of life in a double-blind,randomized clinical trial of imidapril and captopril for hypertensive Chinese in Taiwan

Purpose. Although the role of angiotensin-converting enzyme (ACE) inhibitors for the treatment of hypertension has been well established, no data has been generated regarding the influence of ACE inhibitors for health-related quality-of-life (QOL) dimensions for Chinese patients. Materials. A double-blind, active-control, randomized clinical trial was used to compare the effects of two ACE inhibitors, imidapril and captopril, on quality-of-life dimensions in one outpatient clinic in one tertiary clinical-care facility. After a 2–3 week washout period with placebo, 59 patients with mild-to-moderate hypertension were randomly assigned to receive imidapril (5 to 10 mg per day) or captopril (25 to 50 mg twice per day) for 12 weeks. Patients completed the Short-form 36 (SF 36) health survey questionnaire, which evaluates 8 QOL dimensions, just before treatment, during the 8th week, and at the end of treatment (12th week). ANOVA for repeated measures was used to analyze the QOL-score changes over time and compare treatments, and to assess the interaction of treatment duration and group on these scores. Results. No significant differences were demonstrated for changes in blood-pressure, frequency of adverse effects and withdrawal of patients from the study comparing the two drugs. Significant improvement, however, was demonstrated for mental-component summary scores after 12 weeks of treatment for both drugs (P = 0.029). No significant differences were established for individual QOL dimensions comparing the two drugs. A significantly higher baseline systolic blood pressure was found in the participants who did not complete the questionnaire than in those who did. Conclusions. Similar and significant improvements were determined for the mental-component QOL summary scores for the two ACE inhibitors, imidapril and captopril, and no significant differences were demonstrated comparing treatments.     

Effects of chronic nitrate therapy on left-ventricular volume in patients with heart failure secondary to coronary disease already treated with captopril: a withdrawal study.

OBJECTIVE: This randomized, double-blind, placebo-controlled study with treatment lasting 16 weeks and withdrawal lasting 6 weeks tried to determine whether stopping nitrates has an effect on left-ventricular end-systolic volume in patients with heart failure who were chronically treated with captopril and diuretics. PATIENTS AND METHODS: The study group comprised 29 patients with previous myocardial infarction, symptoms of mild-to-moderate heart failure, ejection fraction below 40%, no exercise-induced angina and no electrocardiographic signs of ischemia. After all patients had been treated with captopril (target dose: 25 mg twice daily), diuretics and the study drug (target dose: 40 mg isosorbide dinitrate twice daily or placebo) for 16 weeks, the study drug was withdrawn. The patients were then maintained on captopril and diuretics at constant doses for a 6-week withdrawal period. Radionuclide ventriculography with right-heart catheterization was performed at rest and during supine bicycle exercise after 16 weeks of double-blind treatment and at the end of the 6-week withdrawal period. RESULTS: The changes in resting parameters following the withdrawal of the study drug were not different between the groups. At comparable maximum workload (placebo group 68 +/- 15 W, nitrate group 68 +/- 20 W), nitrate withdrawal caused a decrease in ejection fraction (placebo withdrawal: +0.8 +/- 4.0%; nitrate withdrawal: -2.7 +/- 4.3%, p < 0.02) and increases in left-ventricular end-diastolic volume (-9 +/- 35 vs. 23 +/- 48 ml, p < 0.02) and end-systolic volume (-9 +/- 33 vs. +24 +/- 47 ml; p < 0.01). CONCLUSION: The addition of nitrates to a baseline therapy with captopril and diuretics might reduce exercise-induced left-ventricular dilatation in patients with heart failure from coronary disease.     

Comparison of enalapril versus captopril on left ventricular function and survival three months after acute myocardial infarction (the “practical” Study)

Left ventricular (LV) function and survival can be improved with captopril when initiated later than 24 hours after acute myocardial infarction. Animal studies suggest additional benefits may be obtained with earlier initiation of angiotensinconverting enzyme (ACE) inhibitors. The effects on LV function of captopril and enalapril initiated within 24 hours of myocardial infarction were studied. Two hundred twenty-five patients with acute myocardial infarction were enrolled within 24 hours of the onset of chest pain. They were randomized to receive either captopril 25 mg three times daily, enalapril 5 mg three times daily, or placebo. LV ejection fraction (EF) and volumes were measured by radionuclide ventriculography at baseline during treatment and at 3 months after a 3-day withdrawal from therapy. The ACE inhibitor group had a significant increase in EF (45 ± 1 to 47 ± 1%; P = 0.005) and significantly attenuated LV dilatation compared with results in the placebo group (175 ± 6 to 189 ± 7 ml in the placebo group vs 168 ± 4 to 172 ± 4 ml in the ACE inhibitor group; P = 0.051 for LV end-diastolic volume; and 99 ± 6 to 108 ± 7 ml in the placebo group vs 94 ± 3 to 94 ± 4 ml; P = 0.026 for LV end-systolic volume). The beneficial effects of ACE inhibitor therapy on LV function were observed irrespective of the degree of initial LV dysfunction and were comparable in both the captopril and enalapril groups. Survival at 90 days and 12 months was significantly improved in the enalapril group (7 placebo, 9 captopril, 1 enalapril [p = 0.038] and 12 placebo, 10 captopril, 2 enalapril [p = 0.022]; deaths at 90 days and 12 months, respectively). Immediate administration of captopril and enalapril improved LV function and prevented LV dilatation after acute myocardial infarction. The benefit was similar with both ACE inhibitors and was in excess of the benefits of optimal conventional therapy.     

Randomized trial of candesartan cilexetil in the treatment of patients with congestive heart failure and a history of intolerance to angiotensin-converting enzyme inhibitors

BACKGROUND: Many patients with congestive heart failure do not receive the benefits of angiotensin-converting enzyme (ACE) inhibitors because of intolerance. We sought to determine the tolerability of an angiotensin II receptor blocker, candesartan cilexetil, among patients considered intolerant of ACE inhibitors. METHODS: Patients with CHF, left ventricular ejection fraction less than 35%, and history of discontinuing an ACE inhibitor because of intolerance underwent double-blind randomization in a 2:1 ratio to receive candesartan (n = 179) or a placebo (n = 91). The initial dosage of candesartan was 4 mg/d; the dosage was increased to 16 mg/d if the drug was tolerated. A history of intolerance of ACE inhibitor was attributed to cough (67% of patients), hypotension (15%), or renal dysfunction (11%). RESULTS: The study drug was continued for 12 weeks by 82.7% of patients who received candesartan versus 86.8% of patients who received the placebo. This 4.1% greater discontinuation rate with active therapy was not significant; the 95% confidence interval ranged from 4.8% more discontinuation with placebo to 13% more with candesartan. Titration to the 16-mg target dose was possible for 69% of patients who received candesartan versus 84% of those who received the placebo. Frequencies of death and morbidity were not significantly different between the candesartan and placebo groups (death 3.4% and 3.3%, worsening heart failure 8.4% and 13.2%, myocardial infarction 2.8% and 5.5%, all-cause hospitalization 12.8% and 18.7%, and death or hospitalization for heart failure 11.7% and 14.3%). CONCLUSIONS: Candesartan was well tolerated by this population. The effect of candesartan on major clinical end points, including death, remains to be determined.     

Haemodynamic, neurohumoral and exercise effects of losartan vs. captopril in chronic heart failure: results of an ELITE trial substudy. Evaluation of Losartan in the Elderly

BACKGROUND: The AT1 receptor antagonists differ from the angiotensin converting enzyme inhibitors by achieving a more complete blockade of angiotensin II's actions and by not affecting bradykinin metabolism. There is little information on whether this causes clinically significant differences in haemodynamics, neurohormones and exercise tolerance in heart failure. AIMS: To compare the effects of losartan and captopril upon central and regional haemodynamics, neurohormones and exercise capacity in heart failure. METHODS: In a double-blind, randomised trial 18 patients aged > or =65 years with symptomatic heart failure were allocated to treatment with losartan (10 patients) or captopril (eight patients). Patients underwent assessment at baseline, after the first dose, at 12 weeks and at 24 weeks. RESULTS: Systolic blood pressure fell by - 10.7% 1 h after captopril 6.25 mg (P = 0.007) and by - 4.8% 3 h after losartan 12.5 mg (P = 0.02). The blood pressure reduction was sustained with losartan at 12 and 24 weeks. Systemic vascular resistance fell acutely after captopril (-16.4%, P = 0.01). Captopril caused an acute and sustained rise in superior mesenteric artery blood flow (+ 22.9%, P = 0.04), and a slower rise in renal artery blood flow (+31.7%, P = 0.01). Losartan had no acute effects on regional haemodynamics but had increased superior mesenteric artery blood flow by 38.1% at 12 weeks (P = 0.02). There were no substantial differences between losartan and captopril, and no changes occurred in neurohormones or exercise capacity. CONCLUSION: No substantial differences were observed between losartan and captopril on central or regional haemodynamics, neurohormones or exercise capacity in elderly patients with stable symptomatic heart failure.     

Lack of effect of nitrates on exercise tolerance in patients with mild to moderate heart failure caused by coronary disease already treated with captopril.

OBJECTIVE--To test the hypothesis that the addition of nitrates improves exercise tolerance in patients with heart failure caused by coronary artery disease already treated with an angiotensin converting enzyme inhibitor and diuretics. DESIGN--Randomised, double blind, placebo controlled, 16 week treatment periods. SETTING--Outpatient clinic at a university hospital. PATIENTS--54 patients with previous myocardial infarction, symptoms of mild to moderate heart failure, left ventricular ejection fraction below 40%, no exercise-induced angina or electrocardiographic signs of ischaemia. Four patients in the nitrate group (n = 24) and one patient of the placebo group (n = 25) were withdrawn from the study. INTERVENTION--After the patients had been on constant doses of captopril and diuretics for at least 2 weeks, they were randomised to receive a target dose of 40 mg isosorbide dinitrate twice daily or placebo in addition to the continuation of captopril and diuretics. MEASUREMENTS--Bicycle exercise tests with measurement of gas exchange were carried out before randomisation and after 1, 6, 12, and 16 weeks of the double blind treatment. The change in peak oxygen uptake from control to week 16 was prospectively defined as the main outcome measure. RESULTS--The increase in peak oxygen uptake from before randomisation tended to be greater in the placebo group (before randomisation 17.4 (3.4) ml/min/kg) than in the nitrate group (before randomisation 17.1 (3.5) ml/min/kg) after 12 weeks (mean increase 1.1 (2.7) v 0.0 (2.7) ml/min/kg, p < 0.12) and 16 weeks (1.7 (3.0) v 0.3 (2.6) ml/min/kg, p < 0.14) of treatment. CONCLUSION--The addition of nitrates to a baseline treatment consisting of captopril and diuretics did not improve exercise tolerance.     

Effect of captopril on functional mitral regurgitation in dilated heart failure: a randomised double blind placebo controlled trial.

OBJECTIVE--To determine the efficacy and dose requirements of captopril to reduce functional mitral regurgitation in patients with dilated heart failure. DESIGN--A randomised double blind placebo controlled parallel arm trial. Incremental daily doses of 25 mg, 50 mg and 100 mg captopril used for a four week period each for a total of 12 weeks preceded by a two week placebo washout. Twenty eight ambulatory patients (mean age 72) New York Heart Association (NYHA) class II or III with apparently controlled ischaemic dilated heart failure (ejection fraction 29% (0.04%)) on digoxin, diuretics, and nitrates were randomised. All had at least grade 2/4 functional mitral regurgitation (> 5 cm2 regurgitant area on colour flow Doppler). RESULTS--Twenty three patients completed the study (13 on placebo and 10 on captopril). Significant improvements were confined to the captopril group. Compared with placebo the following improvements were noted in the captopril treated group: mitral regurgitant area decreased from a threshold at 50 mg/day (p < 0.05, mean (95% confidence interval (95% CI)) 3.1 (0.2 to 6.0) cm2), with a further decrease at 100 mg/day (p < 0.01, mean (95% CI) 5.3 (3.1 to 7.5) cm2). Significant improvements in all the other measurements were noted only after 100 mg/day. Stroke volume increased (p < 0.01, mean (95% CI) 11, (1.4 to 21) ml), systemic vascular resistance decreased (p < 0.05, mean (95% CI) 414 (35 to 793) dyn s cm5), left atrial area decreased (p < 0.05, mean (95% CI) 4.3 (0.03 to 8.6) cm2), and deceleration time increased (p < 0.01, mean (95% CI) 52 ms (7 to 98) ms). Left ventricular diameter decreased marginally (p = 0.06, mean (95% CI) 4 (-0.05 to 9 mm). Duke activity index score increased (p < 0.001, median (95% CI) 6.8 (4.5 to 12) points). Heart rate, mean arterial blood pressure, serum creatinine, and serum potassium did not change with either placebo or captopril. No patient was withdrawn directly due to the side effects of captopril. In an open phase nine placebo patients given captopril in rapid increments reaching 100 mg/day in the fourth week showed similar improvements. CONCLUSION--Captopril is efficacious in reducing functional mitral regurgitation in dilated heart failure. Patients require and must tolerate high doses (50-100 mg/day) for additive effects over supervised conventional treatment to occur.     

Blood pressure response to the first dose of angiotensin-converting enzyme inhibitors in congestive heart failure

Angiotensin-converting enzyme (ACE) inhibitors improve survival in heart failure and delay progression to clinical heart failure in patients with left ventricular dysfunction after myocardial infarction. Increasing numbers of older patients are being considered for such treatment. However, there are reports of excessive and prolonged decreases in blood pressure (BP) after the first dose of some ACE inhibitors. We have studied the hemodynamics, pharmacokinetics, and neurohumoral responses to the first dose of oral captopril 6.25 mg, enalapril 2.5 mg, perindopril 2.0 mg, intravenous enalaprilat 1.5 mg, and perindoprilat 1.0 mg, compared with oral or intravenous placebo in 6 parallel groups of 12 elderly patients each with moderate-to-severe (New York Heart Association classes II-IV) heart failure. Oral dosing with active drugs led to different temporal responses. After captopril, there was an early short-lived decrease in BP. Enalapril led to a later long-lasting decrease, but perindopril was not different from placebo. Intravenous enalaprilat and intravenous perindoprilat each lowered BP to a similar extent. The doses of drugs used appeared to be comparable because plasma ACE inhibition was similar following perindopril or enalapril and also comparing perindoprilat and enalaprilat. These studies indicate that oral ACE inhibitors have different profiles of acute BP changes after the first dose. The explanation is not clear, but could include physicochemical differences in the interaction between prodrug ester and diacid metabolites leading to differences in tissue distribution and local enzyme inhibition.     

Effect of oral captopril on premature ventricular complexes in patients with preserved left ventricular systolic function: A randomized clinical trial

Some studies have suggested that angiotensin-converting enzyme (ACE) inhibition in patients with heart failure is associated with a decrease in frequency of spontaneous premature ventricular complexes (PVCs). It is not clear whether such a finding represents a primary effect of ACE inhibition or, instead, a secondary result of treatment of heart failure. For a primary drug effect to be present, PVC suppression during ACE inhibition should also occur in patients with preserved left ventricular systolic function. We therefore undertook a randomized double-blind placebo-controlled crossover clinical trial to assess the effect of oral captopril (50 mg. b. i. d.) on ventricular arrhythmia frequency in 11 patients with > 30 PVCs/h (during a 48-h ambulatory recording) and a left ventricular ejection fraction of ≥ 45% (measured by radionuclide multigated acquisition scan). Pharmacologic activity of the administered drug was evidenced by an increase in median plasma renin activity to 2. 4 ng/AI/ml/h from a value of 1.1 ng/AI/ml/h during placebo (p = 0.001) and an 8.5 ± 10.3 drop in mean diastolic blood pressure during captopril versus placebo (p < 0.03). During captopril treatment, a mean of 491 ± 378 PVCs/h were observed compared with 389 ± 169 PVCs/h during placebo, a nonsignificant difference. There was also no significant change in left ventricular ejection fraction, plasma catecholamines, or serum potassium during captopril treatment. Thus, ACE inhibition in patients with preserved left ventricular systolic function fails to suppress ventricular ectopic activity. Extrapolated to patients with heart failure, our observations argue against a primary PVC suppressive action of ACE inhibitors but do not rule out possible secondary antiarrhythmic effects of these agents.     

Comparative effects of 2.5 and 5 mg cilazapril versus placebo on daily blood pressure load.

The antihypertensive efficacy of 2.5 and 5 mg cilazapril and placebo in lowering 24-h ambulatory blood pressure (ABP) and BP load were compared in 42 patients with mild to moderate hypertension. After a 2-week placebo run-in period, patients were randomized double-blind to receive either 2.5 mg cilazapril (n = 14), 5 mg cilazapril (n = 14), or placebo (n = 14) for 4 weeks. There were no significant differences in 24-h and awake ABP or in office BP between 2.5 and 5 mg cilazapril. Moreover, the percentage of patients that had BP control (mean daytime ABP less than 90 mm Hg) was 14% in the placebo group, 64% and 71% with 2.5 and 5 mg cilazapril, respectively. Furthermore, the percentage of BP load was similar with both regimens (29 v 36%). These observations indicate that 2.5 and 5 mg cilazapril have equipotent antihypertensive efficacy.     

A parallel study of enalapril and captopril and 1 year of experience with enalapril treatment in moderate-to-severe essential hypertension

Angiotensin converting enzyme (ACE) inhibitors, enalapril (5 to 20 mg twice daily) or captopril (25 to 100 mg thrice daily) and matching ACE inhibitor placebos were given to 32 moderate-to-severe essential hypertension patients who were already on 50 mg hydrochlorothiazide daily. Alpha-methyldopa (250 to 500 mg twice daily) was given to 16 patients following 6 weeks of ACE inhibitor therapy. Both enalapril and captopril significantly (p less than 0.05) lowered the supine and upright blood pressures (BPs) (acutely and long-term) without significant reflex heart rate changes. The BPs of enalapril patients were, however, significantly lower (supine diastolic p less than 0.03, supine systolic p less than 0.05, and upright diastolic p less than 0.04) than those of captopril patients when compared by repeated measures of analysis of variance. Eleven enalapril patients have been followed for 1 year with continued BP control. Skin rash occurred in one captopril patient and reversible renal insufficiency developed in two enalapril patients during the first 16 weeks. It is concluded that (although both ACE inhibitors lowered BP, enalapril was more effective than captopril and twice-daily enalapril was well tolerated during 52 weeks of treatment.     

Dose-related beneficial long-term hemodynamic and clinical efficacy of irbesartan in heart failure

OBJECTIVES: The primary purpose of this study was to determine the acute and long-term hemodynamic and clinical effects of irbesartan in patients with heart failure. BACKGROUND: Inhibition of angiotensin II production by angiotensin-converting enzyme (ACE) inhibitors reduces morbidity and mortality in patients with heart failure. Irbesartan is an orally active antagonist of the angiotensin II AT1 receptor subtype with potential efficacy in heart failure. METHODS: Two hundred eighteen patients with symptomatic heart failure (New York Heart Association [NYHA] class II-IV) and left ventricular ejection fraction < or = 40% participated in the study. Serial hemodynamic measurements were made over 24 h following randomization to irbesartan 12.5 mg, 37.5 mg, 75 mg, 150 mg or placebo. After the first dose of study medication, patients receiving placebo were reallocated to one of the four irbesartan doses, treatment was continued for 12 weeks and hemodynamic measurements were repeated. RESULTS: Irbesartan induced significant dose-related decreases in pulmonary capillary wedge pressure (average change -5.9+/-0.9 mm Hg and -5.3+/-0.9 mm Hg for irbesartan 75 mg and 150 mg, respectively) after 12 weeks of therapy without causing reflex tachycardia and without increasing plasma norepinephrine. The neurohormonal effects of irbesartan were highly variable and none of the changes was statistically significant. There was a significant dose-related decrease in the percentage of patients discontinuing study medication because of worsening heart failure. Irbesartan was well tolerated without evidence of dose-related cough or azotemia. CONCLUSIONS: Irbesartan, at once-daily doses of 75 mg and 150 mg, induced sustained hemodynamic improvement and prevented worsening heart failure.     

Influence of the angiotensin converting enzyme inhibitor cilazapril, the beta-blocker propranolol and their combination on haemodynamics in hypertension

This study compared the antihypertensive effects and the haemodynamic mechanisms of action of an angiotensin converting enzyme (ACE) inhibitor, a beta-blocker and the combination of both in patients with mild to severe hypertension. After a placebo run-in period of 2 weeks, patients were treated for 3 weeks with each of the following: cilazapril (2.5 mg daily) and propranolol (120 mg daily), in a randomized sequence, and thereafter a combination of the two drugs. Blood pressure, cardiac output (measured by Doppler ultrasound) and total peripheral resistance (TPR) in a sitting position at rest were determined. One patient out of 18 was withdrawn in the cilazapril phase. Both monotherapies yielded significant and similar reductions of diastolic blood pressure (average -10 mmHg). Cardiac output and TPR showed opposite effects. Cardiac output was lower with the beta-blocker than with the ACE inhibitor (3.4 versus 4.5 l.min-1), while TPR behaved conversely (2646 versus 2005 dyne.s.cm-5). The combination of both drugs lowered diastolic blood pressure significantly more than the monotherapies (average -20 mmHg); the haemodynamic effects of the monotherapies were attenuated by the combination (cardiac output = 3.7 l.min-1; TPR = 2170 dyne.s.cm-5). A sitting diastolic blood pressure of less than or equal to 90 mmHg could be achieved in six out of 17 patients with propranolol alone, in eight out of 18 with cilazapril alone, and in 14 out of 17 with the coadministration of both drugs. The combination was better tolerated subjectively than the beta-blocker alone.(ABSTRACT TRUNCATED AT 250 WORDS)     

Effect of valsartan on quality of life when added to usual therapy for heart failure: results from the Valsartan Heart Failure Trial

BACKGROUND: The effect on quality of life (QOL) of valsartan administered in addition to prescribed background heart failure therapy was assessed as a secondary endpoint in the Valsartan Heart Failure Trial (Val-HeFT). METHODS AND RESULTS: QOL was assessed in 3010 patients receiving either valsartan (160 mg twice daily) or placebo in addition to prescribed background therapy (beta-blockers or angiotensin-converting enzyme inhibitors), using the Minnesota Living with Heart Failure (MLWHF) questionnaire. Treatment differences were compared at intervals to 36 months after randomization and at endpoint (last observation) using analysis of covariance and repeated measures mixed-effects, and at endpoint using a Mantel-Haenszel chi-squared test. Scores lower than baseline were indicative of improved QOL. Valsartan had a significant beneficial effect on the least-square mean change in overall MLWHF score from baseline to study endpoint (+/- standard error) (average followup 23.0 months) compared with placebo (0.19 +/- 0.47 versus 1.94 +/- 0.48; P = .005 respectively). The placebo group was characterized by a deterioration in QOL as the trial progressed. More patients on valsartan reported a clinically meaningful improvement in MLWHF score (a decrease of > or =5 points) than on placebo (34.0% versus 30.2%). CONCLUSION: Valsartan compared to placebo added to prescribed therapy slows progressive worsening of QOL in patients with heart failure.