TWO AUTOPSY CASES OF RUPTURED PAPILLARY MUSCLE AFTER MYOCARDIAL INFARCTION

Abstract

Two autopsy cases of partial rupture of the left posterior papillary muscle caused by myocardial infarction are reported here. One case was a 68-year-old woman with mitral insufficiency. On admission, a Grade 3 apical pansystolic murmur was heard but there was no thrill. Electrocardiograms revealed an acute inferior myocardial infarction, and she died of acute heart failure caused by a repeat attack on the 8th day of hospitalization. The heart weighed 490 grams at autopsy, and the right coronary artery was completely obstructed by a thrombus. The circumflex of the left coronary was severely arteriosclerotic. The transmural infarction involved the posterolateral wall of the left ventricle, spreading to the septum and posterior walls of the right ventricle. Rupture of the posterior papillary muscle occurred simultaneously with the repeat attack. The other case herein reported is that of a 61-year-old male with diabetes mellitus, angina pectoris and hypertension. Electrocardiograms revealed an acute inferior myocardial infarction. A Grade 3 apical pansystolic murmur was suddenly heard on the 12th day of hospitalization, but there was no thrill. He died of heart failure on the 21st after admission. The heart weighed 490 grams at autopsy and the right coronary artery was completely obstructed by a thrombus. The left oronary arteries were moderately arteriosclerotic. Transmural infarction involved the posterior wall and septum of the left ventricle and an old antero-septal infarction was found. Torsion and twisting ofchordae tendineaein the rupture of the left papillary muscle was found. Neither of these cases had their coronary conditions diagnosed in their lifetimes.