Subclinical Hypothyroidism

A 77-year-old male former smoker with hypertension, dyslipidemia, and diabetes mellitus was admitted to our institution for recurrent syncope. He had a history of previous non–Q-wave inferior myocardial infarction in 1980, which had never been investigated by coronary angiography. Echocardiogram showed left ventricular dilation, inferior akinesia, and hypokinesia of the remaining segments with severe left ventricular dysfunction (left ventricular ejection fraction, 30%). Twenty-four–hour Holter ECG recording revealed 3 episodes of self-terminating sustained ventricular tachycardia. The patient underwent a coronary angiography that evidenced multivessel disease with chronic total occlusion of the proximal right coronary artery and of the mid left circumflex artery and diffuse disease of the left anterior descending artery without critical stenosis. Collateral flow ran from left anterior descending artery to left circumflex artery via diagonal branches (Rentrop 2); mid-distal right coronary artery was supplied by homo- contralateral vessel circulation via left circumflex artery collateral channels (Rentrop 3). No revascularization therapy was performed because both mid-distal right coronary artery and left circumflex artery were supplied by valid collateral flow and the patient was asymptomatic for …