Hibernating myocardium caused by isolated, radiation induced left main stem coronary artery stenosis

A 45 year old man presented with a five week history of worsening exertional dyspnoea and orthopnoea. He had also noted mild, bilateral ankle swelling. The patient had been diagnosed with stage III Hodgkin's lymphoma in 1968 at the age of 21. During the same year he underwent total nodal irradiation followed by chemotherapy in 1971. He had remained entirely asymptomatic over the course of the next 24 years with no evidence of relapse. Cardiac catheterisation undertaken soon after admission revealed a tight left main stem stenosis with a left dominant system. Left ventriculogram showed severe, global hypokinesia, and raised left ventricular end diastolic pressure (22 mm Hg). Urgent coronary artery bypass graft surgery was carried out. He made an uncomplicated recovery and his condition improved sufficiently to allow discharge eight days following the procedure. His heart failure slowly resolved and repeat transthoracic echocardiogram performed six months after surgery showed an unequivocal improvement in left ventricular function. Left ventricular ejection fraction continued to improve and increased from 23% at two months to 42% at two years. He currently remains entirely asymptomatic off all medication.

Keywords: left main stem stenosis;  radiation induced coronary artery disease;  hibernating myocardium