Beneficial effects of nicorandil versus enalapril in chronic rheumatic severe mitral regurgitation: six months follow up echocardiographic study.
OBJECTIVE
It is possible that vasodilator therapy may retard left ventricular (LV) dilatation and functional deterioration in chronic mitral regurgitation (MR). The study objectives were to evaluate comparatively the efficacy of nicorandil (a new, balanced vasodilator) and enalapril therapy on LV volume, mass and function in mildly symptomatic, chronic rheumatic severe MR.


METHODS
Eighty-seven mildly symptomatic rheumatic patients with severe MR were enrolled in this prospective, randomized study. All patients underwent serial echocardiography study at entry, and again at six months. Eighty patients completed the study.


RESULTS
At six months, the nicorandil and enalapril patient groups each had a significant reduction in LV end-systolic volume index (57.4 +/- 24.8 versus 43.2 +/- 20.7 ml/m2, p = 0.003; 50.0 +/- 19.0 versus 40.4 +/- 14.2 ml/m2, p = 0.006, respectively) and LV mass index (218.0 +/- 88.0 versus 188.0 +/- 76.0 g/m2, p = 0.05; 217.2 +/- 48.0 versus 186.2 +/- 45.0 g/m2, p = 0.002 respectively). Both nicorandil and enalapril caused significant improvement in ejection fraction (63.8 +/- 7.0 versus 71.0 +/- 6.7%, p <0.0001; 63.2 +/- 6.9 versus 67.5 +/- 6.4%, p = 0.002, respectively) and a reduction in LV end-systolic stress (152.9 +/- 29.0 versus 126.0 +/- 25.0 dyne/cm2, p = 0.001; 150.0 +/- 30.2 versus 138.0 +/- 29.0 dyne/cm2, p = 0.002, respectively). However, nicorandil caused a greater reduction in absolute LV end-systolic volume index (13.3 +/- 10.1 versus 9.6 +/- 5.9 ml/m2, p = 0.02), and a greater improvement in absolute ejection fraction (7.2 +/- 4.7 versus 4.2 +/- 2.6%, p = 0.0005) than enalapril.


CONCLUSIONS
It is concluded that nicorandil is equivalent to enalapril in improving LV volume, mass, end-systolic stress and ejection fraction in mildly symptomatic chronic rheumatic severe mitral regurgitation over a period of six months.
Gupta
D K
DK
Department of Cardiology, Sanjay Gandhi Postgraduate Institute of Medical Sciences, Lucknow, India.
Kapoor
A
A
Garg
N
N
Tewari
S
S
Sinha
N
N
D000293:Adolescent; D000328:Adult; D000806:Angiotensin-Converting Enzyme Inhibitors / Q000494:pharmacology* / Q000627:therapeutic use*; D002908:Chronic Disease / Q000188:drug therapy; D004656:Enalapril / Q000494:pharmacology* / Q000627:therapeutic use*; D005260:Female; D005500:Follow-Up Studies; D006352:Heart Ventricles / Q000000981:diagnostic imaging / Q000187:drug effects; D006801:Humans; D008297:Male; D008944:Mitral Valve Insufficiency / Q000000981:diagnostic imaging* / Q000188:drug therapy*; D020108:Nicorandil / Q000494:pharmacology* / Q000627:therapeutic use*; D011446:Prospective Studies; D012216:Rheumatic Diseases / Q000000981:diagnostic imaging* / Q000188:drug therapy*; D014463:Ultrasonography; D014665:Vasodilator Agents / Q000494:pharmacology* / Q000627:therapeutic use*; D016277:Ventricular Function, Left / Q000187:drug effects*
D000806:Angiotensin-Converting Enzyme Inhibitors; D014665:Vasodilator Agents; D020108:Nicorandil; D004656:Enalapril