Amlodipine in Ischaemic Left Ventricular Dysfunction with Mild to Moderate Heart Failure

Abstract

Objective: In this study, we evaluated the effectiveness of amlodipine in patients with severe ischaemic left ventricular dysfunction (LVD) and mild to moderate heart failure, but not current angina, assessing the effects of the drug on symptoms, left ventricular function and exercise capacity.

Patients and Methods: We studied 36 patients with ischaemic LVD (radionuclide ejection fraction <40%, left ventricular end-diastolic dimension >60mm) and mild to moderate heart failure (NYHA class II or III) without angina treated with ACE inhibitors (36 of 36), digitalis (34 of 36) and diuretics (30 of 36). Among the 36 recruited patients, 33 fulfilled the study protocol, including 2 weeks of run-in (standard therapy), 8 weeks of treatment (standard therapy + amlodipine 5mg once daily) and 2 weeks of washout (standard therapy). Symptoms graded on a 10-point scale (heart failure score; a higher score representing improvement in symptoms), radionuclide left ventricular ejection fraction (rLVEF), echocardiographic left ventricular end-diastolic dimension (LVEDD), peak aerobic capacity (VO_2max), exercise time (ET) and total work load (TWL) were measured after run-in, treatment and washout periods. All patients underwent coronary angiography and ²⁰¹Thallium (T1) myocardial scintigraphy.

Results: With respect to baseline and washout, after amlodipine treatment the HF score improved (6.6 ±1.3 after amlodipine vs 5.9 ±1 at baseline and 5.9 ±1.1 at washout; p < 0.02), rLVEF increased (33.12 ±9.02% vs 29.14 ±7.72% and 30.02 ±7.39%, respectively; p < 0.001), and VO_2max (14.35 ±4.05 ml/kg/min vs 12.68 ±3.21 ml/kg/min and 12.62 ±3.59 ml/kg/min, respectively; p < 0.003), ET (440 ±169 sec vs 395 ±158 sec and 402 ±162 sec, respectively; p < 0.02) and TWL (2183.2 ±439 kpm vs 1615.5 ±427 kpm and 1708.8 ±437 kpm, respectively; p < 0.01) were also increased. The increase in VO_2max was related to systolic blood pressure at rest and at the peak of exercise, and to the presence of viable and/or ischaemic myocardium at ²⁰¹Tl myocardial scintigraphy.

Conclusion: Amlodipine, in addition to standard therapy (including in all cases an ACE inhibitor), reduced symptoms and improved exercise capacity and ventricular function in patients with mild to moderate heart failure due to myocardial ischaemia. Thus, amlodipine is useful in patients with ischaemic LVD and heart failure without angina. The improvement in exercise capacity was greater in patients with scintigraphic evidence of viable and/or ischaemic myocardium and higher blood pressure. However, our study presented some limitations (i.e. an open study with few patients), and only generated a hypothesis that could lead to a wider, multicentre, cooperative trial.