Electrocardiographs Abnormalities and Coronary Arteriograms in the Mitral Click-Murmur Syndrome

“Ischemic” electrocardiographic changes are frequently associated with a mid-systolic click and late systolic murmur. Neither the cause of these electrocardiographic changes nor the natural history of patients with this syndrome has been determined. Five patients with the auscultatory findings of the “mitral click syndrome,” as well as “ischemic” electrocardiographic changes, were studied because coronary-artery anomalies or disease was suspected. Phonocardiograms were obtained with patient supine and upright, and during amyl nitrite inhalation, Valsalva maneuver and phasic respiration. Four of five graded bicycle exercise tests were normal, and there were no arrhythmias. At catheterization, prolapsed posterior-mitral-valve leaflets and normal coronary arteriograms were found in all five patients. Repeat catheterizations in two patients spanning five and eight years revealed mild progression in severity of the mitral-valve prolapse. In patients with mitral-valve prolapse the associated “ischemic” electrocardiographic abnormalities are apparently not due to large-vessel coronary-artery lesions. (N Engl J Med 289:127–131, 1973). THERE have been several reports of patients with prolapse of one or both mitral-valve leaflets, a mid-systolic click, a late systolic murmur and electrocardiographic ST-segment and T-wave changes similar to those encountered in coronary-artery disease.^{1 2 3} The syndrome sometimes is familial and is probably congenital in origin.⁴ Although the prognosis is usually benign, little is known about the rate of progression of the mitral-valve abnormality. Similar auscultatory findings may occur in acquired mitral-valve disease due to rheumatic fever or coronary atherosclerosis.³,⁵ Differentiation of the congenital click-murmur syndrome from acquired mitral-valve disease is complicated by lack of knowledge concerning the cause and.