Post-infarction ventricular septal rupture detected by means of computed tomography: A case report

Clinical History

Male patient with acute myocardial infarction undergoing a thoracoabdominal CT for abdominal pain and hypotension.

Imaging Findings

An 85-year-old man admitted to the cardiology department for acute posteroinferior myocardial infarction 5 days ago. A thoracoabdominal CT was requested for further evaluation of abdominal pain and hypotension with the suspicion of retroperitoneal haemorrhage. The contrast-enhanced thoracoabdominal CT with 45 seconds delay showed a defect in the ventricular septum suggesting a septal rupture. CT also showed contrast reflux into the inferior cave and hepatic veins suggesting heart failure.

Discussion

Cardiac rupture is a catastrophic complication of acute myocardial infarction. The three potential sites of rupture are the left ventricular free wall, interventricular septum, and papillary muscle. Without rapid surgical correction, each of these complications typically leads to cardiogenic shock, multiorgan failure, and death. Postmortem analysis has identified a small number of cases in which myocardial infarction led to rupture at more than one of these sites; however, there are no reports of survival from such an event. Ventricular septal rupture complicates 1 to 3 % of all infarction and account for 5 % of all peri-infarction deaths. This usually occurs between 2 – 6 days after onset of acute myocardial infarction, although it may occur anytime within about first 2 weeks after an acute infarction. Mortality is high if treated medically and 25 % patients die from cardiogenic shock within 24 hours, and it reaches 90 % at 2 months. Early recognition of this complication using transthoracic echocardiography at patient bedside, and prompt surgical repair are the main factors to achieve long-term survival in these patients. The left-right shunt through the ventricular septal defect produces a right heart failure characterized by low output syndrome with increased jugular venous pressure, increased liver size and hypotension. Típically there is no pulmonary edema (Diferential diagnosis to ruptured papillary muscle). Patients may present with a new murmur associated with a thrill. Right heart catheterization will demonstrate elevated right atrial and pulmonary artery pressures as well as an oxygen step-up at the right ventricular level. Transthoracic echocardiography with Doppler imaging should be used to evaluate and monitor regional and global left and right ventricular function, valvular structure and function, possible pericardial pathology and mechanical complications of acute myocardial infarction. The chest X-ray could show a right sided cardiac enlargement and engorgement of pulmonary vasculature. CT study is not necessary for diagnosis of ventricular septal rupture, but in this case the main suspicion was a retroperitoneal haemorrhage. To our knowledge there are only a few reports of acute ventricular septal rupture showed with CT. Apart from the septal defect, CT also showed signs of right heart failure such as right chamber dilatation and contrast reflux into the inferior cave and hepatic veins.

Differential Diagnosis List

Final Diagnosis

Post-infarction ventricular septal rupture.

URL:	https://www.eurorad.org/case/5115
DOI:	10.1594/EURORAD/CASE.5115
ISSN:	1563-4086