Retrograde CTO-PCI Using an Internal Thoracic Bypass Graft Segment in a Patient with Acute Inferior ST-Elevation Myocardial Infarction and Cardiogenic Shock.

Background: Percutaneous coronary intervention (PCI) of the "culprit" artery is the recommended mechanical reperfusion strategy in the setting of ST-segment elevation myocardial infarction (STEMI). As PCI of bypass grafts may be associated with higher risks and lower procedural success rates, in patients with a history of previous coronary artery surgery, PCI directed at revascularization of the native vessels should be considered, but this may be difficult in the setting of a chronically occluded artery. Case Presentation: A patient with a history of multivessel coronary artery disease and a chronic total occlusion (CTO) of the right coronary artery (RCA) requiring arterial bypass surgery, presented with an acute inferior STEMI and cardiogenic shock. It was felt that shock was caused by the acute thrombotic occlusion of a right internal thoracic artery (RITA) bypass graft that had been sequentially anastomosed to the left circumflex (LCx) and right coronary arteries. Despite initiation of extracorporeal membrane oxygenation (ECMO), the patient remained in refractory shock and acute revascularization of the right coronary artery was performed through the RITA bypass segment using antegrade access to the graft through the LCx and then a retrograde approach to open a CTO of the RCA. After successful revascularization, the patient was successfully weaned from ECMO. Over 12 months of follow-up, the patient did well and was documented to have improved left ventricular systolic function. Conclusion: This report is the first to document the successful use of a retrograde approach through an arterial graft segment to revascularize a chronic total occlusion in the setting of acute STEMI and cardiogenic shock.