Diffuse and severe left ventricular dysfunction induced by epicardial coronary artery spasm

Endothelial dysfunction and effectiveness of treatment of calcium antagonis ts are suggestive of coronary artery spasm as an underlying disorder in dil ated cardiomyopathy (DCM). The aim of this study is to determine whether or not the epicardial coronary artery spasm can induce severe cardiac dysfunc tion like DCM. Thirty-four consecutive patients with angiographically norma l coronary arteries and diffuse left ventricular hypokinesis whose causes h ad been unknown underwent acetylcholine provocation test and left ventricul ar biopsy. Eight patients were excluded according to the clinical and labor atory data and biopsy findings suggesting myocarditis or other systemic dis eases; According to the results of the acetylcholine provocation test, 17 p atients were finally diagnosed as having DCM, and nine patients (35% of the study patients), who had acetylcholine-induced diffuse and multivessel cor onary spasm, were diagnosed as having DCM-like vasospastic angina pectoris (VSA). Clinical and cardiac catheterization data including hemodynamics and biopsy findings were similar between the two groups except that left ventr icular end-systolic volume was significantly greater in DCM than in DCM-lik e VSA. After the acetylcholine provocation test, DCM patients received both a beta blocker and an angiotensin-converting enzyme inhibitor, and DCM-lik e VSA patients received antianginal drugs. In echocardiographic findings at predischarge and those after 6-month drug treatment, both DCM-lke VSA and DCM showed significant reduction in end-diastolic and end-systolic diameter s and significant increase in fractional shortening and ejection fraction, whereas changes in ejection fraction and fractional shortening were signifi cantly greater in DCM-like VSA than those in DCM. Epicardial coronary arter y spasm can induce diffuse and severe left ventricular dysfunction like DCM in VSA. Although antianginal drugs markedly improve left ventricular funct ion of these patients, only the acetylcholine provocation test can identify DCM-like VSA.