Right ventricular infarction.

Right ventricular myocardial infarction, long unrecognized because of a lack of diagnostic methods and unsupported beliefs regarding the dispensability of the right ventricle, may now be diagnosed using well-accepted criteria. Right ventricular infarction is clearly associated with anterior left ventricular infarction as well as inferior infarction. It may occur in 30% to 40% of patients with inferior infarction, although a much smaller percentage experience hemodynamic instability on the basis of right ventricular infarction. Pathophysiologically, right ventricular systolic and diastolic dysfunction are exacerbated by pericardial restraint and concomitant left ventricular dysfunction, accounting for the characteristic findings of cardiogenic shock and marked preload dependence in many patients. Right ventricular infarction may be suspected on the grounds of clinical presentation, physical examination, and enzymatic findings, and is confirmed using well-defined electrocardiographic, radionuclide, echocardiographic, and hemodynamic criteria. Once diagnosed, right ventricular infarction requires specific hemodynamic and pharmacologic management, including the judicious use of volume expansion and inotropic support. Several forms of mechanical and surgical intervention are of therapeutic value in treating hemodynamic disturbances and recognized complications. With appropriate management, the prognosis for patients with right ventricular infarction is generally favorable.