DCardiologist in Vidyaranyapura, Bangalore • etected vascular abnormalities Calcium scoring High-resolution CT scanners can measure calcium within the coronary arteries in a single breath-hold scan. The measured calcium is given a number, the Agatston score. The presence of calcium within a coronary artery is a marker of coronary disease but not of obstructive disease. It does not give any information about the presence of soft plaque, which is more likely to be associated with an acute coronary event but a 0 score predicts a very low coronary risk. A high score has been shown to be an independent risk factor for future events.29 Prospective studies proving the value of calcium scoring have not been performed. Calcium scoring is likely to be superseded by multi-slice CT coronary angiography (p. 136), which can produce images of the coronary lumen and generate a calcium score. An elevated calcium score in an asymptomatic patient is probably best treated as an indication for aggressive risk factor management; for example, instituting statin treatment for a marginally elevated cholesterol level. Intima-media thickness High-frequency ultrasound transducers can measure accurately the thickness of the carotid intima up to its interface with the media. An intima-media thickness (IMT) of > 1.3 mm is associated with an increased cardiovascular risk, which remains significant after allowing for other risk factors. Ankle brachial index The ankle brachial index (ABI) is relatively easy to measure with a sphygmomanometer and a Doppler ultrasound device. The systolic blood pressure in the arm and in the posterior tibial and dorsalis pedis arteries is compared. An ABI of < 0.9 means a stenosis of at least 50% somewhere between the aorta and the foot. The test is a reliable sign of peripheral arterial disease and thus also coronary disease. Erectile dysfunction Erectile dysfunction is a marker of endothelial dysfunction. Because the penile arteries are smaller (1–2 mm) than the carotids (5–7 mm) and coronary arteries (3 mm), plaque burden and endothelial dysfunction may cause symptoms earlier here than in the other territories. hsCRP measurements and risk of vascular events (stroke, myocardial infarction, acute coronary syndrome) Low risk Intermediate High hsCRP level < 1 mg/L 1–3 mg/L > 3 mg/L Note: levels > 10 mg/L suggest acute inflammation and should be repeated after a few week In some studies erectile dysfunction has reliably preceded symptomatic coronary disease in twothirds of patients by an average of three years.30 A history of this problem in men indicates an increased risk of vascular events. It is strongly associated with other risk factors such as smoking and diabetes but remains significant after allowing for these. Infectious agents There is continuing mild interest in the role of infection in promoting atherosclerosis and especially unstable coronary syndromes. Chlamydia pneumoniae and Helicobacter pylori are commonly found in atheromatous plaques. It is possible one or more infectious agents could be the stimulus that sets off the inflammatory process that changes plaque structure, weakens the fibrous cap and unleashes the coagulation cascade that occludes the vessel. The ACADEMIC study was not associated with a reduction in early coronary events