The difficulty of adequate risk stratification for patients with asymptomatic diabetes.

A 43-year-old man with type 2 diabetes mellitus was referred for cardiovascular risk assessment 2 years ago. Other risk factors for coronary artery disease included hypercholesterolemia, smoking, and a family history of coronary artery disease. The patient was asymptomatic. Physical examination was unremarkable; his body mass index was 22 kg/m and his blood pressure was 125/80 mm Hg. Hypercholesterolemia was well regulated with statin administration (total cholesterol 3.52 mmol/L, low-density lipoprotein cholesterol 2.23 mmol/L, high-density lipoprotein cholesterol 0.94 mmol/L). ECG showed normal sinus rhythm and no additional abnormalities (Figure 1). Myocardial perfusion imaging was performed with gated single-photon emission computed tomography (SPECT) using technetium-99m sestamibi (500 MBq). Pharmacological stress was induced with adenosine; the stress ECG showed no abnormalities. On gated SPECT, left ventricular ejection fraction was 68% during stress as well as at rest; myocardial perfusion imaging revealed no perfusion abnormalities during stress or at rest (Figure 2). In addition, no coronary calcium was observed during calcium scoring (total coronary calcium score 0). However, contrast-enhanced multislice computed tomographic coronary angiography revealed the presence of diffuse nonobstructive ( 50% luminal narrowing), noncalcified plaques, as illustrated in Figure 3. Risk factor modification was advised (exercise, stop smoking) and aggressive medical therapy was initiated (administration of aspirin, statins, and an ACE inhibitor).