Rupture of the ventricular free wall is a most feared complication and accounts for 8-15% of all infarct deaths and up to 10% of hospital deaths post-MI. Most ruptures (84%) occur in the first week and 32% in the first day. The most common presentation is sudden hemodynamic collapse followed by rapid demise with or without clinical signs of tamponade.
This complication is more commonly seen in the anterior or lateral wall of the left ventricle and usually is preceded by infarct expansion. In some instances, rupture may be heralded by episodes of recurrent pericardial pain, at times with features of pericardial effusion, hypotension, and tamponade. If treatment is to be successful, diagnosis must be prompt and management aggressive. Interventions include infarctectomy, closure of viable myocardial wall, and bypass surgery.
Is surgical intervention required immediately in patients with papillary muscle rupture or interventricular septal rupture?
These two complications post-MI have an abrupt onset, with rapid development of a new systolic murmur, pulmonary edema, and shock. Prognosis depends on the degree of rupture, severity of mitral regurgitation, and previous left ventricular function. Initial therapy usually consists of hemodynamic support, including inotropic and vasodilator therapy, guided arterial and pulmonary artery catheterization, and on occasion, the use of an intraaortic balloon pump. If hemodynamic stability is not achieved with these measures and if the patient remains hypotensive, then surgical intervention is required immediately. However, perioperative mortality is high, ranging from 35-50%. In patients who achieve hemodynamic stability with medical therapy, surgery is usually delayed 6-12 weeks in an attempt to improve healing around the infarct margins, thus facilitating surgery as well as lowering the mortality rate.