95. What is the treatment for an acute ventricular septal defect after a myocardial infarction?

Emergency surgical repair is warranted in the setting of an acute ventricular septal defect. Without surgical intervention, the mortality rate is > 90%. Fortunately, with the early revascularization techniques now employed (PCI), VSD formation is less common. An intraaortic balloon pump (IABP) can be used to improve hemodynamics reduce afterload

When infarction of the interventricular septum occurs, this area can thin with the remodeling process and on occasion, a complete defect between the right and left ventricles can develop. This results in left to right shunting of blood and can be life-threatening when acute. A holosystolic murmur at the left lower sternal border occurs. Right heart catheterization will show an “oxygen step-up” between the right atrium and right ventricle (since oxygenated blood will be present in the right ventricle).

The ventricles are good at adapting to hemodynamic stress when gradually introduced, as in worsening aortic regurgitation, however when acute, ventricular failure and shock occurs as is present with acute VSD formation.