Myocardial infarction in a patient with mirror-image dextrocardia.

T incidence of coronary artery disease (CAD) in those with situs inversus (SI) is similar to that in the general population.1 Dextrocardia with complete SI occurs in approximately one per 10,000 live births,2 and is accompanied by congenital heart disease (usually transposition of the great vessels) in only 3-5% of cases.3 Patient having this anomaly and presenting with myocardial infarction (MI) may pose difficulty to be diagnosed by routine electrocardiogram (ECG), provided the ECG is carried out with all the leads in reversed direction. Here, we describe a patient having anteroseptal MI with mirror image dextrocardia in the Intensive Care Unit (ICU) Department of King Faisal Hospital, Makkah, Kingdom of Saudi Arabia. There are 2 types of dextrocardia; isolated dextrocardia, and mirror image dextrocardia. In isolated dextrocardia with SI (dextroversion), the body organs other than the heart are normal whereas in the mirror image dextrocardia with SI totalis, all the body organs are a mirror-image of the normal arrangement. Our objective is to provide physician’s awareness on the extent of MI in such patient that may be underestimated unless dextrocardia is timely recognized, and ECG leads reversed. This means left and right limb leads should be swapped for both arms and legs, and the chest leads should run around the right side of the chest (using the same intercostal spacing locations) rather than the left. A 55-year old male patient admitted to the Emergency Room (ER) with history of chest pain, and suddenly collapsed. The patient was connected to a mechanical ventilator and was brought to the ICU. Heart sounds were not clearly audible on the left side, but clear on the right side. The ECG from ER is shown in Figures 1a & b. The chest x-ray is shown in Figure 2. A second ECG with the leads in reversed direction was carried out in ICU (Figure 1), and showed abnormal Q waves in leads V1, V2 and V3. Poor R wave progression from V1-V4 with ST depression from V2-V5 was suggestive of anteroseptal MI. Transthoracic 2-dimensional echo was performed, which showed left ventricle on the right side and right ventricle on left side with basal to mid anteroseptal akinesia, basal to distal lateroseptal akinesia, basal to distal anterior wall akinesia, and apical akinesia. Subcostal view showed the inferior vena cava on the left side. The apical view showed the liver on the left side. The ejection fraction was 35%. Laboratory results showed that total creatinine kinase was 1959 units/L (normal range [NR]: 55-170 units/L), creatine Clinical Note