Potential risk of provisional stenting in left main coronary artery bifurcation in multivessel-related acute coronary syndrome.

We present a case of an elderly man suffering from an acute coronary syndrome (ACS) with preshock vital signs and remarkable ST-T wave depression in leads V4-V6, and ST elevation in lead aVR. Coronary angiography showed total occlusion of the right coronary artery (RCA) and impending occlusion in the distal left main coronary artery (LMCA) with a tandem lesion in the proximal left anterior descending artery (LAD). After insertion of an intra-aortic balloon pump both the LAD and left circumflex artery (LCX) were dilated alternatively; and cross-over stenting in the LMCA bifurcation was subsequently performed. However, total occlusion of the LCX occurred and it caused acute hemodynamic collapse and ventricular fibrillation storm. Immediate installation of percutaneous cardio-pulmonary support system allowed stent deployment to be performed in the RCA and subsequent reopening of the LCX that led to a return to sinus rhythm. The patient recovered almost normal left ventricular wall motion and previous activity without any neurological deficit within 2 weeks. Provisional stenting in ACS in the LMCA bifurcation with multivessel disease has a potential risk of acute hemodynamic collapse; a planned two-stent deployment strategy may assure a higher rate of safety in such cases.