We aim to describe the in-hospital outcomes of the first reported Canadian cohort of patients with cardiogenic shock and acute myocardial infarction (MI) due to acute and total occlusion of the left main coronary artery, treated with initial percutaneous coronary intervention (PCI). Acute left main thromboses with cardiogenic shock were identified (N = 8) from a retrospective consecutive cohort of high risk left main PCI (N = 56) performed at our institution from 2004-2009. The mean age was 62.3 ± 13.2 years, with 6 (75%) male patients. Successful PCI was performed in all patients, with thrombectomy utilized in 4 patients (50%), stenting in 7 patients (88%), and intra-aortic balloon pump augmentation in 7 patients (88%). Two patients (25%) required extracorporeal membrane oxygenation (ECMO) and 2 other patients required ventricular assist devices. Post-PCI coronary artery bypass grafting (CABG) was performed for 2 patients (25%). The mean SYNTAX score was 26.6 ± 10.5. The mean logistic EuroSCORE was 30.4 ± 12.6%. In-hospital mortality occurred in 3 patients (38%). Acute left main occlusion is a rare but devastating presentation of myocardial infarction, invariably with cardiogenic shock. Emergent PCI may be an effective method to acutely revascularize this subset of patients; however, aggressive post-PCI care including ECMO, CABG, and ventricular support may be required to improve patient survival.