Impending Interventricular Septal Rupture After CABG: Conservative Management of a Post-Infarction Septal Pseudoaneurysm

Background : Ventricular septal defect is a rare yet life-threatening mechanical complication of myocardial infarction. In exceptionally uncommon cases, the interventricular septum undergoes localized dissection with formation of an intraseptal pseudoaneurysm without complete septal rupture. While most pseudoaneurysms develop in the acute post-infarction phase, delayed presentation following surgical revascularization is exceedingly rare. Case Summary : We report the case of a 61-year-old man who underwent surgical coronary artery bypass grafting after myocardial infarction. Early postoperative transesophageal echocardiography identified a 3 × 3 cm mid-septal pseudoaneurysm without communication between the two ventricular chambers. Given the patient’s hemodynamic stability, a conservative strategy with combined anticoagulation and antiplatelet therapy was adopted. Serial transesophageal echocardiographic follow-up demonstrated progressive spontaneous thrombosis and complete closure of the pseudoaneurysm. At six months, the patient remained asymptomatic with preserved left ventricular function. Discussion : Post-CABG interventricular septal pseudoaneurysm is an exceptionally rare finding. In carefully selected hemodynamically stable patients, conservative management may represent a reasonable alternative to surgery, as spontaneous thrombosis and resolution can occur. Close echocardiographic surveillance is essential to guide therapeutic decisions and promptly detect complications. Conclusion : This case highlights that early diagnosis and individualized management of post-CABG interventricular septal pseudoaneurysm may lead to favorable outcomes without surgical intervention in selected stable patients.