Background <p>Myocardial necrosis following acute myocardial infarction may result in three major mechanical complications: papillary muscle rupture, free-wall rupture, and ventricular septal rupture (VSR), all of which are associated with devastating hemodynamic consequences and may compromise short-term survival. Although the incidence of these complications has markedly declined with the widespread adoption of early percutaneous coronary interventions, the surgical management of VSR remains highly demanding and requires substantial expertise. Moreover, the optimal timing of surgery remains controversial, with partially conflicting recommendations, as North American guidelines for STEMI advocate urgent VSR closure regardless of hemodynamic status, while European guidelines recommend early surgery only in cases of refractory cardiogenic shock or severe right ventricular dysfunction. The occurrence of a VSR followed by a delayed FWR several months later remains exceptionally rare and reflects specific myocardial rupture patterns.</p> Case presentation <p>We report the case of a 55-year-old caucasian male patient with a history of multiple surgical procedures for ventricular septal rupture, followed by a delayed FWR complicated by a giant pseudoaneurysm. Three months later, the patient was urgently referred to our department for recurrence of a giant mycotic pseudoaneurysm caused by <i>Propionibacterium acnes</i>, which was successfully treated using a large pericardial patch reinforced with a transdiaphragmatic pedicled omental flap.</p> Conclusions <p>This case, characterized by severe and complex complications involving infectious mechanisms with technically demanding surgical management, provided an opportunity to review the literature regarding these challenging issues and to underscore the potential role of the omental flap as an effective immunological adjunct to address <i>Propionibacterium acnes</i> devastating infections.</p>