Isolated Right Ventricular Infarction Resulting From Occlusion of a Nondominant Right Coronary Artery
A 58-year-old man with no history of heart disease presented to the emergency department having experienced 1 hour of progressive chest pain. His heart rate was 80 bpm and his blood pressure was 176/92 mm Hg; the results of the physical examination were otherwise unremarkable. The administration of sublingual nitroglycerine caused a precipitous drop in his blood pressure to 90/50 mm Hg. A 12-lead ECG showed a 1-mm ST-segment elevation in leads III, aVF, and V1 (Figure 1A). The placement of right-sided precordial leads revealed a 2-mm ST-segment elevation in lead V4R (Figure 1B). Emergency coronary arteriography demonstrated a left dominant coronary circulation with nonobstructive disease in the left anterior descending coronary artery and the posterior descending branch of the left circumflex coronary artery and a total occlusion of the proximal right coronary artery distal to the conus branch (Figure 2A). The nondominant right coronary artery occlusion was managed with balloon dilation and stenting (2.25 mm×15.0 mm stent), resulting in the immediate resolution of chest pain and ST-segment elevation (Figure 2B). The peak creatine kinase-MB level was 10.1 ng/mL, and the peak troponin T level was 0.37 ng/mL. Subsequent echocardiography was normal, and the patient recovered without sequelae. Clinically recognized right ventricular myocardial infarction resulting from a nondominant right coronary artery is rare. Previous reports indicate that ECG changes may be less dramatic than those that were observed in our patient.