Uncommon electrocardiographic presentation of an isolated right ventricular myocardial infarction

Abstract

Isolated right ventricular myocardial infarction is an extremely rare condition, and its diagnosis may be challenging. We present the case of a 63-year-old man who arrived at the emergency department with chest pain; electrocardiogram showed ST-segment elevation in precordial leads, for which, the diagnosis of anterior ST-elevation myocardial infarction was initially made. Coronary angiography showed diffuse coronary artery ectasia and total thrombotic occlusion of the right coronary artery that was treated by angioplasty and stenting, resulting in resolution of the chest pain and ST-segment elevation. Echocardiogram showed right ventricular systolic dysfunction and cardiac magnetic resonance confirmed the diagnosis of isolated right ventricular myocardial infarction. We highlight the value of invasive and non-invasive tests to diagnose this rare condition. <Learning objective: Isolated right ventricular myocardial infarction is a very uncommon, but important differential diagnosis of anterior ST-elevation myocardial infarction. There exist certain electrocardiographic features favoring its diagnosis, although, recognition requires a high index of suspicion and support in different modalities of study including cardiac magnetic resonance and coronary angiography. Proper identification of it, will help to guide treatment and support for possible complications.>.

Keywords: Cardiac magnetic resonance; Coronary artery ectasia; Electrocardiographic diagnosis; Isolated right ventricular myocardial infarction.

Fig. 1

Electrocardiographic findings. (A) Initial electrocardiogram (ECG) showing convex ST-segment elevation in the anterior precordial leads V1 to V4, with peak elevation in V2 and progressive reduction in ST-segment elevation across the precordial leads, minor ST-segment depression in the inferior leads and clockwise rotation of the heart is also observed. (B) Post-coronary angioplasty ECG showing normal sinus rhythm with resolution of ST-segment elevation and no anterior Q waves.

Fig. 2

Coronary angiography. (A, B, C) Diffuse coronary ectasia was observed in left anterior descending artery and circumflex artery, both vessels with thrombolysis in myocardial infarction (TIMI) flow grade 2. (D) Right coronary artery with total thrombotic occlusion in the proximal segment. (E, F, G, H) Right coronary artery angioplasty and stenting with final TIMI flow grade 3.

Fig. 3

Single photon emission computed tomography/computed tomography imaging (A) and cardiac magnetic resonance imaging (B). (A) A normal polar map of left ventricular perfusion, with no change in the images between rest and stress. (B) Short axis (a, b, c) and right two-chamber axis (d) showing transmural late enhancement (arrows) of the free and inferior wall of the right ventricle. No late enhancement was observed in left ventricle.