Outcome Analysis After Surgical Management of Ventricular Septal Defect Complicating Acute Myocardial Infarction

Abstract

Introduction: Surgical approaches to closure of post myocardial infarction ventricular septal defect (PIVSD) are associated with high morbidity and mortality. Timing of intervention for its closure remains controversial. Several studies advocate early operative intervention, after diagnosis of PIVSD but these are associated with high mortality. However, the strategy of delayed closure around 14 to 20 days or higher has been advocated in certain subsets of patients who can be stabilized from cardiogenic shock (CS) with pharmacological means with or without temporary mechanical circulatory support (tMCS). This helps to allow tissue fibrosis around PIVSD which increases the chance of operative success. Results of 5 such patients in whom surgery was moderately delayed, and 2 in whom early operation were performed are reported in this paper. Material and methods: Between May 2012 to April 2016, 7 consecutive patients of PIVSD had operative closure under cardio pulmonary bypass in our hospital. 5 patients had diuretic and inotrope responsive CS and had delayed closure of PIVSD within 12 to 20 days, while 2 with severe CS, who were supported preoperatively with tMCS like intra aortic balloon pump (IABP), had early closure within 72 hours. Patient data of these seven subjects were retrospectively collected, and the current status of the survivors was ascertained by out patient follow up. Results: 4 of 5 patients from delayed surgery group with small PIVSD survived while 1 patient had early mortality due to severe right ventricular dysfunction post operatively resulting in LCOS. 1 patient out of the 2 early surgery group with a large PIVSD survived while the other patient with a small PIVSD and an extensive MI had early post operative mortality. 1 had from late surgery group had delayed mortality after 3 years. 4 patients are living at present. Conclusion: We advocate delayed elective repair of PIVSD, in patients with CS who responded to aggressive conservative management maintaining hemodynamic stability, to allow inflammatory state to subside. In those patients with severe CS, additional rescue therapy with temporary mechanical circulatory support is needed to prevent further deterioration of systemic perfusion. If the severe CS is due to high left to right shunt rather than infarct size, prognosis after repair of PIVSD is better than in patients with CS due to extensive myocardial damage.