In patients with inferior myocardial infarction, what portion may also present with right ventricular myocardial infarction?

In patients experiencing inferior myocardial infarction, the involvement of the right ventricle can occur due to the anatomy of the coronary circulation, particularly if there is occlusion in the right coronary artery (RCA), which supplies blood to both the inferior wall of the left ventricle and the right ventricle. Approximately one-third of patients with an inferior STEMI will also exhibit signs of right ventricular myocardial infarction, especially if the inferior wall MI is caused by RCA occlusion.

The right ventricle is crucial in maintaining cardiac output, and its dysfunction can exacerbate hypotension and other complications stemming from inferior myocardial infarction. Recognition of right ventricular involvement is vital, as management strategies may differ significantly, often requiring volume resuscitation and careful monitoring of hemodynamics to avoid further compromise to the patient's condition.

This understanding emphasizes the importance of assessing ECG changes and hemodynamic parameters in patients with inferior myocardial infarctions, as these can indicate concurrent right ventricular infarction in about one-third of cases.