Ventricular Septal Rupture as a Complication of Myocardial Infarction

Abstract

A 75-year-old woman with a history of hypertension was admitted to the hospital. Three weeks earlier she had presented to another hospital with an episode of chest pain and acute anterior myocardial infarction (MI). An echocardiogram (Echo) obtained post-MI demonstrated an apical left ventricular (LV) aneurysm with thrombus, and the patient was started on warfarin. She was discharged from the hospital but readmitted (10 days after the initial MI) with acute shortness of breath necessitating intubation. At that time an Echo demonstrated a large collection of pericardial fluid; pericardiocentesis yielded approximately 600 cc of bloody fluid. Because of ongoing chest pain, selective coronary angiography was performed. This demonstrated significant stenoses in the left anterior descending and left circumflex coronary arteries as well as possible stenosis in the right coronary artery. After the patient was extubated, a loud holosystolic murmur was noted. Another Echo demonstrated a large, apical LV aneurysm with poor global LV function (ejection fraction ≈15%). In addition, an apical ventricular septal defect (VSD) was now apparent, with left-to-right shunting. The patient was then transferred to our institution.On arrival, we found the patient elderly, alert and responsive, and in no acute distress. Blood pressure was 105/60 mm Hg and heart rate was 81 bpm. Examination was notable for basilar rales and wheezes in both lungfields. Cardiac rhythm was regular, with a broad and dyskinetic left ventricular apex impulse. A grade 3/6 holosystolic murmur was audible at the apex and along the left sternal border. Peripheral pulses were intact, and no edema was noted. The admission electrocardiogram demonstrated Q waves in leads V 2 -V 5 , with ST-segment elevations in the midprecordial leads unchanged from previous tracings and consistent with LV aneurysm.A bedside transthoracic Echo at our institution demonstrated a large, apical LV aneurysm (Figure 1) with systolic dyskinesis. The basal half of the left ventricle demonstrated relatively preserved systolic contractile function. Global LV ejection fraction, measured using the apical biplane method of discs, was 13%. In addition, modified apical views demonstrated a discontinuity in the apical portion of the ventricular septum, and Doppler color flow imaging demonstrated communication at this site with leftto-right shunting (Figure 2). The right ventricle (RV) was not overtly dilated, and global RV function was reasonably well preserved. Only mild tricuspid regurgitation was present. Both tricuspid regurgitation and VSD velocities suggested that RV systolic peak pressure was ≈50 mm Hg. Significant valve malfunction was not apparent. Hospital CourseThe demonstration of apical VSD approximately 10 days following an initial acute anterior MI was thought to be quite consistent with post-MI septal rupture. Although the risks of surgical VSD closure were believed to be elevated because of the patient's age, depressed global LV function, and large apical LV aneurysm, it was clear tha...

Papillary Muscle Rupture Following Myocardial Infarction

“…Incompetence of the mitral valve can result from a variety of causes. Additionally, papillary muscle rupture, 2 papillary muscle ischemia, 3 fibrosis and retraction, 4 impairment of systolic mitral closure due to impaired LV systolic function, 5 and dilation of the mitral annulus can cause MR. Of course, the presence of a new systolic murmur and worsening heart failure can also signal the development of post‐MI septal rupture, a condition that was discussed in a previous issue of The American Heart Hospital Journal 6 …”