Urgent operation for acquired ventricular septal defect

Surgical Repair of Mechanical Complications of Myocardial Infarction

Mechanical complications of acute myocardial infarction are estimated to account for 25,000 fatalities yearly in the United States. The diagnosis necessitates a high degree of clinical suspicion. Once recognized, prompt surgical intervention is necessary because if left untreated the condition frequently causes a fatal outcome. The main determinants of survival are the preoperative hemodynamic status of the patient, the presence of multisystem failure at presentation, and concomitant revascularization during repair of the defect. Because ischemic heart disease remains the leading cause of death in such patients following repair, coronary artery bypass should be considered and, whenever possible, performed in conjunction with repair of the postinfarct mechanical complication.

Prolonged intraaortic balloon support for septal rupture after myocardial infarction

Timing of surgical repair of ventricular septal defect developing after acute myocardial infarction remains controversial. We report the case of a 75-year-old man in whom a ventricular septal defect developed 7 days after myocardial infarction. The patient was maintained on intraaortic balloon pump support for 33 days before successful surgical closure. In the present era of aggressive preoperative hemodynamic management, the strategy of prolonged support before definitive operation on patients with myocardial infarction in whom a ventricular septal defect develops must be reconsidered.

A new technique for bridging to heart transplantation: feasibility of monoventricularization of bilateral ventricles with LVAD

Because the prognosis of ventricular septal perforation (VSP) and mitral regurgitation (MR) after acute myocardial infarction (MI) is remarkably poor, heart transplantation would be necessary for many of those patients. A new bridging technique was examined in canine models. The bilateral ventricles communicating through VSP were monoventricularized with mitral valve closure and maintained the pulmonary circulation, which had low vascular resistance. The systemic circulation was maintained by a left ventricular assist device (LVAD) placed between the left atrium and the aorta. VSP and MR were made in eight mongrel dogs (pulmonary to systemic flow ratio = 2.24 +/- 0.90). They were then monoventricularized and equipped with LVADs. The hemodynamic state was evaluated (a) in intact hearts, (b) after VSP and MR were made, and (c) after monoventricularization and assisted circulation by LVAD. Cardiac output was (a) 90.60 +/- 23.16, (b) 42.23 +/- 15.76, and (c) 73.43 +/- 15.14 ml/min/kg (a vs. c: not significant; a vs. b and b vs. c: p less than 0.001); mean aortic pressure was (a) 96.75 +/- 24.69, (b) 30.25 +/- 11.08, and (c) 66.50 +/- 18.40 mm Hg (a vs. b: p less than 0.01, a vs. c and b vs. c: p less than 0.05); central venous pressure was (a) 4.76 +/- 1.68, (b) 8.94 +/- 2.17, and (c) 10.68 +/- 2.43 mm Hg (a vs. c: p less than 0.01, a vs. b: p less than 0.05, and b vs. c: not significant). Mean pulmonary arterial pressure and mean left atrial pressure did not show any significant difference among the three groups.(ABSTRACT TRUNCATED AT 250 WORDS)

Correlates of survival in patients with postinfarction ventricular septal defect

Prognostic indicators of survival in 42 consecutive patients (21 men and 21 women) with postinfarction ventricular septal defect were reviewed. Infarct location was anterior in 57%, inferior in 33%, and combined in 10%. The hospital mortality among 9 patients not receiving surgical therapy was 100%. Of the 33 surgically treated patients, 19 (58%) survived. Time from diagnosis to operation, ventricular function, and presence or absence of shock were analyzed in a logistic regression model to determine which factors carried independent prognostic value. Shock was independently predictive of operative mortality (p less than 0.01). Of additional variables examined, nonsurvivors were characterized by a shorter time from postinfarction ventricular septal defect to operation, a relatively higher incidence of inferior infarction, moderate right ventricular dysfunction and mild left ventricular dysfunction, and a lower right ventricular systolic pressure. Results of postmortem examination were available for 15 nonsurvivors. Quantitative analysis of percent ventricle infarcted revealed that in patients with inferior infarctions, a mean of 31% of the right ventricle was infarcted compared with 10% in patients with anterior infarction (p = 0.059). Kaplan-Meier survival estimates revealed 1-year survival of 70%, 5-year survival of 55%, and 10-year survival of 20%. Seventy percent of survivors were in New York Heart Association class I or II. These data show that, irrespective of ventricular function or timing of operation, the development of shock is the most important predictor of survival in postinfarction ventricular septal defect. The higher mortality in patients with inferior infarction may be associated with a greater degree of right ventricular infarction and consequent dysfunction. Finally, long-term survival and excellent functional recovery can be achieved in patients undergoing operation.

Surgical treatment of ventricular septal rupture complicating myocardial infarction

A review of postinfarction ventricular septal defects repaired surgically at Providence Hospital over the past 6 years is presented. Although this complication of myocardial infarction carries a high mortality rate, a lower rate can be achieved with early operative intervention. Preoperative pharmacologic reduction of preload, afterload, and intra-aortic balloon pumping are only temporizing measures to allow delineation of concomitant lesions. Operative mortality does not appear to be influenced by posterior location of the ventricular septal defects.

Hemodynamic abnormalities in acute myocardial infarction

Great strides have been made in the management of patients with acute myocardial infarction since the advent of coronary care units. However, congestive heart failure continues to be the major cause of in-hospital mortality. The accurate diagnosis and classification of hemodynamic abnormalities allow the application of specific therapies for each patient. Because clinicians can now routinely measure left and right ventricular preload, systemic and pulmonary vascular resistance, cardiac output, and arteriovenous oxygen difference, pharmacologic and surgical interventions can be applied in a scientific manner. In addition, mechanical complications can be promptly recognized and aggressively treated. Although the mortality rate for patients with severe left ventricular dysfunction after myocardial infarction remains high, expert management offers an improved prognosis for many patients.