Acute myocardial infarction in a patient with dextrocardia and situs inversus

We report a case of 54-year-old man who presented to hospital with severe prolonged retrosternal chest pain of anginal nature. Electrocardiogram taken by his general practitioner showed minimal ST elevation in chest leads V1 and V2; there was also marked right axis deviation of P wave (negative in lead I and aVL) and of QRS complexes, together with low voltage in precordial leads V4 through V6 suggestive of dextrocardia. Repeat electrocardiogram with chest and limb leads reversed showed widespread, significant ST elevation in lead I, aVL, and V1 through V5 in keeping with extensive acute anterior myocardial infarction (MI). High cardiac enzymes and troponin level provided further confirmation. The extent of MI in such patients may be underestimated unless dextrocardia is timely recognized and leads reversed. We recommend that for patients with dextrocardia and situs inversus presenting with MI, both chest and limb leads be reversed to reveal the true extent of the infracted area.