Comparison of late survival in patients with cardiogenic shock due to right ventricular infarction versus left ventricular pump failure following primary percutaneous coronary intervention for ST-elevation acute myocardial infarction.

This study compared late survival after primary percutaneous coronary intervention (PCI) in patients with cardiogenic shock due to right ventricular (RV) infarction versus left ventricular (LV) pump failure. Consecutive patients with ST-elevation myocardial infarction treated with primary PCI (n = 2,496) were prospectively enrolled in a registry from 1984 to 2004. Cardiogenic shock occurred before PCI in 189 patients (7.6%). Shock was attributed to predominant RV infarction when there was right coronary artery occlusion with preserved LV function and increased right atrial pressure. Patients with shock due to RV infarction (n = 30) versus LV pump failure (n = 136) had fewer previous infarctions (10% vs 29%, p = 0.03), less multivessel disease (20% vs 47%, p = 0.007), higher right atrial pressure (21 vs 16 mm, p = 0.003), and better LV ejection fraction (57% vs 32%, p <0.001). In-hospital mortality was lower with shock due to RV infarction (23% vs 50%, p = 0.01), and shock due to RV infarction was a significant independent predictor of late cardiac survival (hazard ratio 0.28, 95% confidence interval 0.13 to 0.62, p = 0.002). In conclusion, survival after primary PCI in patients with shock due to RV infarction is better than that in patients with shock due to LV pump failure. This is in contrast to most previous reports. Improved survival is likely related to lower risk profile and previously documented substantial recovery of RV function after primary PCI.