Pathophysiology of cardiogenic shock: quantification of myocardial necrosis.

Clinical and pathologic data were correlated in 22 patients with cardiogenic shock and 10 "control" patients who died suddenly after infarction without shock. A pathologic technique of ventricular mapping allowed quantification of recent as well as old infarction. Total left ventricular (LV) damage averaged 51% (range 35-68%) in the shock patients and 23% (range 14-31%) in the control group. Shock was associated with recent infarction (all 22 patients), old infarction (21 patients) and extension of infarction (18 patients). Extension, often in a subepicardial manner, averaged 6% of LV mass (range 3-10%) in 18 patients with shock; it preceded shock in four, coincided with the onset of shock in six, and followed shock in seven patients with shock. In contrast, small extensions averaging 2% of LV mass were found in three, and multiple recent infarctions in two control patients. Although progressive myocardial damage was a common pathologic finding, it was infrequently recognized clinically. The electrocardiogram reflected evidence of recent infarction in 56%, old infarction in 31%, and extension in only 30% of patients. These data suggest that appropriate early therapeutic intervention might limit myocardial damage by preventing extension or reinfarction. Since shock was best correlated with total LV damage, such limitation of infarction might reduce the incidence and mortality of cardiogenic shock.