Enalapril in the treatment of congestive heart failure

Analysis of ambulatory heart failure management and its incidence on one-year survival

AIM

To assess in a daily practice survey one-year survival in a cohort of patients with heart failure (HF) according to their clinical profiles and the way they were managed by cardiologists.

METHODS AND RESULTS

A prospective observational survey was conducted in 1941 patients with HF followed up for one year. Results show high rates of prescription for ACE inhibitors, indicating that cardiologists take into account international recommendations. ACE inhibitors are prescribed at dosage levels approaching those recommended by the guidelines. However, beta-blocker prescription still shows a significant deficit and the prescribed doses are much lower than those currently recommended. The multifactorial modeling analysis showed that global heart failure (P=0.004), advanced NYHA class (P<0.001), renal failure (P<0.001) were predictive of poor outcome whereas an increased survival likelihood was observed in patients given ACE-inhibitor/beta-blocker combination compared with beta-blocker alone or ACE-inhibitor alone.

CONCLUSION

The results from this study should enhance the prescription of ACE inhibitors and beta-blockers at effective doses in compliance with the guidelines. They also suggest that a synergic positive effect of the combination of these two therapeutic classes is observed in real life situations.

The origin of sympathetic outflow in heart failure: the roles of angiotensin II and nitric oxide

The regulation of sympathetic nerve activity in chronic heart failure (CHF) has been an area of renewed investigation. Understanding the central mechanisms that are responsible for sympatho-excitation in this disease state may help in reducing the deleterious effects of chronic sympatho-excitation. This review will summarize our understanding of abnormal reflex control of the circulation in CHF. The roles of the arterial baroreflex, the chemoreflex, the cardiac sympathetic afferent reflex and the cardiopulmonary reflex are discussed. New experimental techniques that allow genetic manipulation of substances such as nitric oxide synthase in discrete areas of the brain aid in clarifying the role of NO in the modulation of sympathetic tone in the CHF state. Lastly, clinical implications of this work are discussed.

Ambulatory heart failure management in private practice in France

Management of ambulatory heart failure was assessed in a group of 600 patients, mean age 73, 64% males, NYHA I: 9%; II: 52%; III: 33%; IV: 6%; followed up by a representative sample of private cardiologists. Fifty-two percent of patients had been previously hospitalised for worsening heart failure with a mean duration of stay of 13.1 days, for those hospitalised in the year preceding the survey (26%). First diagnosis of heart failure had been performed by a cardiologist (57%), a general practitioner (37%) or another category of physician (6%). Seventy percent of patients received three or more different classes of heart failure medications. Diuretics were prescribed to 71%, angiotensin converting enzyme inhibitors to 54% and digitalis to 35% of the population. Beta-blockers were given to only 14% of the patients. In patients aged over 80 years, only 45% received angiotensin converting enzyme inhibitors.

CONCLUSION

This survey of ambulatory heart failure patients confirms that the disease is predominantly observed in elderly patients, and associated with prolonged and recurrent hospitalisations. The underuse of recommended therapeutic classes including angiotensin converting enzyme inhibitors and beta-blockers deserves further investigation.

Controlled clinical evaluation of enalapril in dogs with heart failure: results of the Cooperative Veterinary Enalapril Study Group. The COVE Study Group

The clinical efficacy and safety of enalapril were evaluated in dogs with moderate or severe heart failure. This study was conducted at 19 centers and included 211 client-owned dogs with heart failure caused by mitral regurgitation (MR) due to acquired valvular disease or dilated cardiomyopathy (DCM). Dogs of various breeds, ages, and weights were included in the study. Replicates of 2 dogs each were formed, using separate allocation schedules for dogs with MR or DCM. One dog within each replicate received placebo tablets (vehicle tablets without enalapril) PO sid or bid, and the other dog received enalapril tablets at approximately 0.5 mg/kg sid or bid, based on individual need. In addition to the experimental drug, all dogs, except 1 in the placebo group, received furosemide; 73.3% of the dogs in the placebo group and 78.3% of those in the enalapril group received digoxin. Doses of enalapril or placebo were administered for approximately 28 days. In the placebo group, 68.6% of the dogs completed the study compared with 84.9% in the enalapril group; the difference between groups was significant (P < .01). Significantly (P < .01) more dogs in the placebo group compared with the enalapril group died or were removed from the study because of progression of heart failure. On day 28, all 14 clinical variables measured improved significantly (P < .01) in the enalapril group compared with the placebo group. Five dogs (3 from the placebo group and 2 from the enalapril group) had to be removed from the study as a result of azotemia.

Acute and short-term hemodynamic, echocardiographic, and clinical effects of enalapril maleate in dogs with naturally acquired heart failure: results of the Invasive Multicenter PROspective Veterinary Evaluation of Enalapril study. The IMPROVE Study Group

The efficacy of enalapril maleate in dogs with naturally acquired class III or class IV heart failure was evaluated in a multicenter study. Fifty-eight dogs with dilated cardiomyopathy (35 dogs), mitral regurgitation (22 dogs), or aortic regurgitation (1 dog) receiving conventional therapy for heart failure (furosemide with or without digoxin) were included in a randomized double-blind study. Thirty-one dogs received enalapril tablets PO at approximately 0.5 mg/kg body weight bid, and 27 dogs received placebo tablets PO bid. Physical, electrocardiographic, hemodynamic, echocardiographic, radiographic, and clinical examinations were performed on each dog before treatment and at the end of the approximately 21-day study. After treatment on day 0, the enalapril-treated dogs had significantly (P < .05) lower heart rate, mean systemic arterial blood pressure, and mean pulmonary arterial blood pressure than the placebo-treated dogs. Pulmonary capillary wedge pressure was marginally decreased (P = .0567) in the enalapril-treated dogs. When compared with those in the placebo-treated dogs, scores for pulmonary edema were significantly (P < .05) decreased on day 2 in the enalapril-treated dogs. At the end of the study, enalapril-treated dogs had significantly (P < .05) greater decreases in class of heart failure, pulmonary edema score, and mobility score relative to baseline, and had significantly (P < .05) better overall evaluation scores when compared with the placebo-treated dogs. This study shows the beneficial hemodynamic and clinical effects of adding enalapril to conventional therapy for dogs with heart failure.

Effects of captopril and enalapril on renal function in elderly patients with chronic heart failure

OBJECTIVE

To compare the effects on renal function of captopril and enalapril in elderly patients with chronic heart failure.

DESIGN

A multi-centre double-blind parallel-group comparison of the two angiotensin-converting enzyme (ACE) inhibitors, captopril (12.5 mg bid) and enalapril (2.5 mg bid).

SUBJECTS

80 elderly patients with chronic heart failure (41 in the captopril group, 39 in the enalapril group).

MAIN OUTCOME MEASURES

The blood pressure and pulse rate response to the first dose of ACE inhibitor was assessed in all patients. Glomerular filtration rate (GFR) was measured radioisotopically by 99mTcDTPA or 51CrEDTA clearance after three and six months of each treatment. Subgroups were assessed for effective renal plasma flow (33 patients), exercise tolerance (25 patients) and by a symptom-oriented questionnaire (45 patients).

RESULTS

No serious adverse effect on GFR was noticed. There was no significant difference between the two treatments in the mean baseline GFR or in changes from baseline at three and six months (captopril mean baseline GFR 49.6 ml min-1 1.76 m-2, enalapril 54.7 ml min-1 1.76 m-2; mean change (95% confidence interval) at three months captopril 12 ml min-1 (+3.0, +21.0), enalapril -2 ml min-1 (-13.0; +9.0); mean change at six months, captopril 3.7 ml min-1 (-6.7; +14.2), enalapril -6.0 ml min-1 (-21.0; +9.4). Significantly more patients given captopril had an improvement in GFR during the study period (26/31 compared with 20/31 enalapril-treated patients at three months, p = 0.0096, and 23/30 compared with 15/27 at six months, p = 0.021). There were no significant changes in effective renal plasma flow. Three patients treated with enalapril developed symptomatic hypotension within three days of starting treatment. Quality of life questionnaires revealed more gastrointestinal symptoms in the enalapril group (p = 0.039).

CONCLUSIONS

Captopril seems marginally preferable to enalapril in the treatment of chronic heart failure in elderly patients.