Answer

ECG showed extensive evolved anterior wall myocardial infarction (MI), q-waves and ST elevation in all anterior and lateral leads with reciprocal ST changes in inferior leads [Figure 1]. Transthoracic echocardiography demonstrated a simple ventricular septal rupture (VSR) (arrow) and dyskinetic anterolateral wall and interventricular septum [Figure 2], color Doppler [Figure 3], and continuous wave Doppler [Figure 4] showing left-to-right shunt across VSR.

Discussion

This patient admitted to the Department of General Medicine with acute anterior wall MI thrombolysed with streptokinase, came to the Cardiology Department on day 3 of admission in hemodynamically stable state for cardiologist opinion. VSR was picked up during examination and echocardiography.

VSR is a rare and lethal complication of acute myocardial infarction (AMI). In the prethrombolytic era, VSR was thought to complicate 1%–2% of AMI presentations.^[1] More contemporary series, however, show it to be increasingly rare, complicating between 0.17% and 0.31% of patients presenting with AMI.^[2],[3] About 60% of VSRs occur with infarction of the anterior wall, 40% with infarction of the posterior or inferior wall.

Risk factors for VSR in patients presenting with AMI-older age, female sex, prior stroke, chronic kidney disease, thrombolysis, and congestive heart failure. Interestingly, VSR/myocardial rupture is less likely in patients with a history of hypertension, diabetes, prior smoking, or prior MI.

There are very few reported cases of MI, followed by an asymptomatic VSR^[2] similar to this case report. The size of the defect determines the magnitude of the left-to-right shunt and consequently the hemodynamic deterioration, which affects survival.

There are three types of VSR: Type I is an abrupt tear in the wall without thinning; Type II results due to infarcted myocardium eroding before rupture and is covered by a thrombus; and Type III represents the perforation of a previously formed aneurysm.^[2]

There are two main surgical techniques for post-MI VSR repair: one uses patch closure of VSR with infarct excision and the other uses infarct exclusion. The latter technique is now more commonly used as it has better results. Even in asymptomatic patients like the one in our case, should undergo surgical repair given the high mortality with unrepaired VSR.

Percutaneous device closure of VSR/residual VSR after surgical repair can also be done in cases where a significant shunt persists, but results are not encouraging. With appropriate timely surgical intervention the mortality rate can be reduced to 30%–40% from 90%.^[4]