enalapril and Aortic-Valve-Stenosis

Animal models have demonstrated a benefit of angiotensin-converting enzyme inhibitors (ACEI) in experimental aortic stenosis (AS), and intravenous nitroprusside has shown hemodynamic improvements in AS with left ventricular (LV) dysfunction. Although routinely used in most heart failure situations, ACEI are avoided in AS because of the risk of hypotension. We aimed to determine the clinical tolerance and efficacy of the ACEI enalapril in the setting of symptomatic severe AS.. Patients with symptomatic severe AS were enrolled in a randomized, double-blinded, controlled trial to enalapril or placebo arms after initial stabilization. Standard antifailure medications were continued. Enalapril was started at 2.5 mg bid and increased to 10 mg bid. The primary end points were development of hypotension and improvements in Borg dyspnea index and 6-minute walk distance at 1 month. Secondary end points were minor ACEI intolerance, cough, presyncope, improvement in New York Heart Association class, and echocardiographic parameters.. Fifty-six patients were enrolled (37 in the enalapril arm and 19 in the placebo arm). Enalapril was tolerated without hypotension or syncope when LV systolic function was preserved. Three of 5 patients with LV dysfunction and congestive heart failure had hypotension and were withdrawn. Patients who tolerated enalapril (n = 34) demonstrated significant improvement in NYHA class, Borg index (5.4 +/- 1.2 vs 5.6 +/- 1.7, P =.03), and 6-minute walk distance (402 +/- 150 vs 376 +/- 174, P =.003) compared with control subjects. Within the enalapril group, patients with associated regurgitant lesions improved the most.. ACEI are well tolerated in symptomatic patients with severe AS. Patients with congestive heart failure with LV dysfunction and low normal blood pressure are prone to have hypotension. Enalapril significantly improves effort tolerance and reduces dyspnea in symptomatic AS.

Topics: Adult; Angiotensin-Converting Enzyme Inhibitors; Aortic Valve Stenosis; Double-Blind Method; Enalapril; Exercise Tolerance; Female; Humans; Male; Middle Aged; Pilot Projects; Prospective Studies; Severity of Illness Index

We examined whether impaired renal function causes thickening of the aortic valve leaflets in hyperlipidemic apoE-knockout (apoE-/-) mice, and whether the putative effect on the aortic valves could be prevented by inhibiting the angiotensin-converting enzyme (ACE) with enalapril.. Thickening of the aortic valve leaflets in apoE-/- mice was induced by producing mild or moderate chronic renal failure resulting from unilateral nephrectomy (1/2 NX, n = 18) or subtotal nephrectomy (5/6 NX, n = 22), respectively. Additionally, the 5/6 NX mice were randomized to no treatment (n = 8) or enalapril treatment (n = 13). The maximal thickness of each leaflet was measured from histological sections of the aortic roots.. Leaflet thickness was significantly greater in the 5/6 NX mice than in the 1/2 NX mice (P = 0.030) or the unoperated mice (P = 0.003). The 5/6 NX mice treated with enalapril had significantly thinner leaflets than did the untreated 5/6 NX mice (P = 0.014).. Moderate uremia causes thickening of the aortic valves in apoE-/- mice, which can be attenuated by ACE inhibition. The nephrectomized apoE-/- mouse constitutes a new model for investigating the mechanisms of uremia-induced aortic valve disease, and also provides an opportunity to study its pharmacologic prevention.

Topics: Angiotensin-Converting Enzyme Inhibitors; Animals; Aortic Valve; Aortic Valve Stenosis; Apolipoproteins E; Creatinine; Disease Models, Animal; Enalapril; Fibrosis; Hyperlipidemias; Kidney; Male; Mice; Mice, Inbred C57BL; Mice, Knockout; Nephrectomy; Renal Insufficiency; Renin-Angiotensin System; Urea; Uremia

The effects of chronic treatment with the new sulfhydryl angiotensin-converting enzyme (ACE)-inhibitor, zofenopril, in comparison with the classical sulfhydryl ACE-inhibitor captopril or enalapril or placebo on the development of atherosclerosis were determined in apolipoprotein-E knockout (apoE(-/-)) mice. Groups of 2-month-old male mice received either placebo (N=10), 0.05 mg/kg/day of zofenopril (N=10), 1 mg/kg/day of zofenopril (N=10), 5 mg/kg/day of captopril (N=10) or 0.5 mg/kg/day of enalapril (N=8). After 29 weeks of treatment, computer-assisted imaging analysis revealed that zofenopril reduced the aortic cumulative lesion area by 78% at 0.05 mg/kg/day and by 89% at 1 mg/ml/day of zofenopril compared to that of the placebo (P<0.0001). Captopril reduced by 52% aortic lesions compared to placebo (P<0.01 vs. placebo; P<0.05 vs. zofenopril at both doses). Enalapril did not reduce aortic lesions. Furthermore, 0.05 mg/kg/day of zofenopril reduced susceptibility of plasma LDL to in vitro oxidation compared to captopril, enalapril or placebo, as shown by significant reduction of malondialdehyde content (P<0.001 vs. placebo or enalapril; P<0.05 vs. captopril), as well as by the prolongation of lag-time (P<0.01 vs. placebo or enalapril P<0.05 vs. captopril). More importantly, mice treated with 1 mg/ml/day of zofenopril had a significant decrease in the intimal immunohistochemical presence of oxidation-specific epitopes on oxLDL (NA59 monoclonal antibody, P<0.01), macrophages derived foam cells (F4/80 monoclonal antibody, P<0.05) and native LDL (NP monoclonal antibody, P<0.01) compared to placebo, captopril or enalapril. Thus, chronic treatment with the new sulfhydryl ACE-inhibitor zofenopril has antiatherosclerotic and antioxidant effects in the arterial wall of hypercholesterolemic apoE(-/-) mice. This protection was significantly higher than that reached with captopril and at lower doses of the drug. Treatment with 0.5 mg/kg/day of enalapril did not provide any protective effect.

Topics: Angiotensin-Converting Enzyme Inhibitors; Animals; Aortic Valve Stenosis; Apolipoproteins E; Arteries; Arteriosclerosis; Blood Pressure; Captopril; Cholesterol; Disease Models, Animal; Dose-Response Relationship, Drug; Enalapril; Epitopes; Immunohistochemistry; Lipid Peroxidation; Lipoproteins, LDL; Male; Mice; Mice, Knockout; Oxidation-Reduction; Oxidative Stress; Peptidyl-Dipeptidase A; Random Allocation; Sulfhydryl Reagents; Time Factors; Treatment Outcome