The Contest Between Magnetic Resonance and Computed Tomographic Coronary Angiography

Noninvasive coronary imaging is often considered the Holy Grail among cardiologists and radiologists interested in the diagnosis and treatment of coronary atherosclerosis.1–3 That noninvasive coronary imaging would aid in establishing new prevention and treatment strategies in a wide range of clinical scenarios, ranging from early subclinical diagnosis of atherosclerosis in asymptomatic individuals to evaluation and monitoring of coronary stenoses in symptomatic patients with new onset of symptoms or with known coronary artery disease. Remarkable engineering accomplishments have made it possible to visualize the coronary arteries although they are small, tortuous, and do not run in a single plane. Cardiac and respiratory motion makes it difficult to “freeze” the heart to create a sharp coronary image. Two noninvasive diagnostic modalities have emerged, magnetic resonance coronary angiography (MR-CA) and computed tomographic coronary angiography (CT-CA), that allow visualization of the coronary arteries. Each technique has its own advantages and disadvantages (Table 1), and comparison of both contemporary techniques is the obvious way to establish which would be preferable in current clinical practice.