Right ventricular ischemia in patients with primary pulmonary hypertension

OBJECTIVES The goal of this study was to determine whether right ventricula r (RV) ischemia is a contributory factor in the development of RV dysfuncti on in patients with primary pulmonary hypertension (PPH). BACKGROUND Patients with advanced PPH develop RV dysfunction, characterized by a decreased cardiac output, increased right atrial pressure (RAP) and/o r elevated RV end-diastolic pressure, which progresses to heart failure and death. The cause of this dysfunction is unknown. Right ventricular ischemi a may play a role in its development. METHODS From 1992 to 1999, a prospective study involving 23 patients with P PH at the Instituto Nacional de Cardiologia "Ignacio Chavez" (Mexico City, Mexico) was undertaken. These patients were evaluated clinically and furthe r studied by echocardiography, right heart catheterization and stress myoca rdial scintigraphy using technetium 99m sestamibi. RESULTS Nine patients of 23 were found to have scintigraphic images consist ent with RV ischemia. Significant correlation was found between RV ischemia obtained through myocardial perfusion scintigraphy and elevation of RV end -diastolic pressure (p < 0.001), elevation of RAP (p < 0.037) and a decreas e in mixed venous oxygen saturation (p < 0.0001). No other clinical or hemo dynamic variables showed a significant correlation with RV ischemia. CONCLUSIONS A direct correlation exists between RV ischemia, as determined by myocardial scintigraphy, and hemodynamic alterations suggestive of RV dy sfunction in patients with PPH. (C) 2001 by the American College of Cardiol ogy.