Severe diffuse hypokinesis of the remote myocardium--the main cause of cardiogenic shock? An echocardiographic study of 75 patients with extremely large myocardial infarctions.

Two-dimensional echocardiography was performed in 75 patients with extensive myocardial infarctions to prove why cardiogenic shock develops only in a minority of such patients. 23 patients with clinical signs of shock formed group A, and 52 patients without signs of shock group B. The extent of akinesis and/or dyskinesis was the same in both groups. The "Asynergy Index"--involving also hypokinesis--was more favourable in group B (126 +/- 28, compared with 158 +/- 23 in group A, p less than 0.05). The ejection fraction was significantly higher in group B (33 +/- 12%, compared with 17 +/- 6% in group A, p less than 0.01). The cause of these differences was severe diffuse hypokinesis of the remote myocardium, which was present in all 23 patients with cardiogenic shock and only in 2 patients without shock (p less than 0.001). All 23 patients with shock had multi-vessel disease, which was present only in 19% of patients without shock (p less than 0.01). The study shows that in addition to two known conditions necessary for the development of cardiogenic shock (multi-vessel disease and infarct size at least 40% of the left ventricle), there exists a third condition of equal importance: severe diffuse hypokinesis of the remote myocardium.