Background: Peripheral arterial disease (PAD) has the risk equivalent of coronary heart disease. The biochemical parameters associated with functionally significant coronary artery stenosis were investigated in asymptomatic patients with PAD who were scheduled for major vascular intervention.
Methods: A total of 50 PAD patients asymptomatic for coronary heart disease were examined using coronary computed tomography angiography (CTA). A stress myocardial CT perfusion (CTP) test was performed in patients who exhibited coronary stenosis >40%. In patients with stress-induced perfusion defects, the severity of stenosis was assessed using invasive coronary angiography including fractional flow reserve assessment. The CT findings were correlated with both classical and more recently developed parameters of atherosclerosis.
Results: According to the combined CT examination (CTA and stress CT perfusion), 36% of patients exhibited significant coronary stenosis. Stress-induced hypoperfusion was observed in 95.7% of severe stenotic lesions. After adjustment for confounders, the level of high-sensitivity troponin I was associated with severe coronary stenosis (OR 1.260 [95% CI 1.054 to 1.505]). Other biochemical parameters did not correlate with coronary stenosis. The annual mortality rate was 4%.
Conclusions: The results of the present study confirm a significant diagnostic contribution of a complex cardiac CT examination in patients scheduled for major vascular surgery. A high prevalence of asymptomatic coronary heart disease was observed in this particular patient group. High-sensitivity measurements of troponin I correlated with the extent of the coronary stenosis.