The correct answer is C. This patient is having a right ventricular infarct. The triad of jugular venous distention, hypotension, and clear lungs should make you suspect the diagnosis. In addition, the electrocardiogram shows inferior ST-segment elevation (II, III, and aVF), which is consistent with RV infarct. Right-sided electrocardiogram can be used to support this diagnosis. The finding of elevations in lead V4 on a right-sided electrocardiogram is 100% specific for a right-sided infarct. The management of right ventricular infarct requires aggressive fluid resuscitation, as this type of myocardial infarction is fluid-dependent. The patients sustaining this type of infarction are now preload-dependent. They require aggressive intervention to keep the preload high. Aggressive intravenous fluids therefore should be started until the patient stabilizes or goes for cardiac catheterization. Intravenous fluids should be first-line in maintaining adequate blood pressure.
Dopamine (choice A) also might be a useful adjunct if blood pressure cannot be maintained with intravenous fluids alone. Remember that cardiac pressors, although good at maintaining blood pressure, can increase cardiac ischemia, because they increase peripheral vascular resistance. Pressors are helpful at maintaining blood pressure in this setting at the expense of increasing myocardial oxygen demand.
Furosemide (choice B) is potentially harmful to patients who have right ventricular infarction because of this type of infarct's dependence on preload. This patient has borderline blood pressure and clear lungs. Furosemide would decrease preload and therefore decrease cardiac output.
Metoprolol (choice D) is used in most patients who have acute coronary syndrome, but it should not be used in patients who have bradycardia or hypotension. The patient's systolic blood pressure is only 82 mm Hg. Beta-blockers should not be used in a patient who has borderline blood pressure, because they will further lower the patient's blood pressure.
Nitroglycerin (choice E) must be avoided in patients who have right ventricular infarcts. Nitroglycerin is a potent preload reducer. It will decrease right ventricular filling and therefore decrease cardiac output.
PEARL: Right ventricular infarct should be considered in all patients who present with ST-segment elevation in the inferior leads, hypotension, and clear lungs. These patients should not receive any medications that will decrease preload (e.g., nitrates, diuretics). The treatment of choice is fluids to increase the preload.
