Dr. Chatterjee then reviewed several clinical causes of hemodynamic compromise in patients with acute MI. After briefly mentioning the very common cause of left ventricular systolic or diastolic dysfunction, he spent most of his time talking about less common causes (two examples of which are inappropriate autonomic response and right ventricular infarction).

Inappropriate autonomic response is characterized by three signs: (1) hypotension, (2) an inadequate increase in systemic vascular resistance and heart rate, and (3) normal or low cardiac output. Treatment includes atropine and atrial pacing. In hypovolemic shock, both right and left ventricular preloads are decreased. Treatment involves volume expansion and monitoring the patient for changes in right atrial pressure and pulmonary capillary wedge pressure.

Another subset of patients presenting with hemodynamic compromise is made up of individuals with right ventricular infarction. In these patients, hemodynamic parameters are affected by pericardial constrictive pressure and decreased left ventricular preload. There may also be impairment of left ventricular contractile function, although the mechanism for this is not known. These patients should not receive major volume loading because that will worsen diastolic function; inotropic agents may be effective. Treatment should include (1) adequate reperfusion, (2) inotropic drugs, and (3) atrial-ventricular sequential pacing in patients with atrioventricular block. Volume loading may be appropriate in some patients with very low right atrial pressures.