Chronic draining xiphisternal fistula associated with fractured right coronary artery stent and transdiaphragmatic inflammatory extension: a multimodality imaging and surgical correlation

BACKGROUND: Delayed coronary stent-related inflammatory complications following percutaneous coronary intervention (PCI) are exceptionally rare, and chronic cutaneous fistulization years after stent implantation has only rarely been described. Such indolent presentations may mimic superficial chest wall infections, making diagnosis challenging. Multimodality imaging is essential for accurate diagnosis and surgical planning. CASE PRESENTATION: A 53-year-old man with type 2 diabetes mellitus and ischemic heart disease underwent right coronary artery (RCA) stenting in 2018. He presented with recurrent intermittent fever and a persistent draining xiphisternal sinus for seven months following incision and drainage of a presumed chest wall abscess. Ultrasonography demonstrated a localized subcutaneous collection. Contrast-enhanced computed tomography and CT coronary angiography (CTCA) revealed a fractured, chronically occluded RCA stent with extensive peri-stent inflammatory soft tissue extending into the pericardium, diaphragm, and subdiaphragmatic region. Cardiac magnetic resonance imaging confirmed transdiaphragmatic inflammatory extension and a fistulous tract communicating with the overlying skin. Transesophageal echocardiography was not performed because transthoracic echocardiography and cross-sectional imaging adequately delineated the lesion and showed no evidence of endocarditis. Following preoperative and perioperative antibiotic therapy, the patient underwent surgical excision of the fractured stent, chronic fibro-inflammatory tissue, and sinus tract. Intraoperative cultures and GeneXpert testing were negative, possibly reflecting prior prolonged antibiotic therapy. The postoperative course was uneventful, with complete wound healing, resolution of fever, and follow-up transthoracic echocardiography demonstrating no pericardial collection or valvular vegetations. CONCLUSIONS: This case highlights an exceptionally rare delayed culture-negative chronic peri-stent inflammatory fistulizing process associated with RCA stent fracture presenting nearly seven years after PCI. It emphasizes the importance of maintaining a high index of suspicion in patients with persistent chest wall sinuses after coronary intervention and demonstrates the complementary role of CTCA and cardiac magnetic resonance imaging in defining disease extent and guiding successful surgical management.