BACKGROUND: As primary percutaneous coronary intervention (PCI) has been commonly performed for acute myocardial infarction (AMI), we rarely encounter ventricular septal rupture (VSR), which is one of the mechanical complications of AMI. However, the associated mortality rate is still very high unless treated appropriately.

CASE REPORT: We encountered a very rare case of VSR that was considered to have occurred during primary PCI for AMI. The manifestation of sudden coronary flow disturbance may correspond with the emergence of VSR. We introduced a veno-arterial extracorporeal membrane oxygenation (ECMO) system for sudden hemodynamic instability. As a result, the existence of VSR under the operation of the ECMO system led to unusual hemodynamics in the heart, but the vital signs were stabilized by ECMO. VSR was surgically treated and the patient fully recovered without any neurological or physical sequelae.

CONCLUSIONS: Although we now encounter markedly fewer mechanical complications of AMI in this era of primary PCI, we should always be conscious of its possibility in the acute phase of myocardial infarction.

Keywords: acute coronary syndrome, case reports, Ventricular Septal Rupture