64-MDCT angiography of the coronary arteries: Nationwide survey of patient preparation practice

OBJECTIVE. The purpose of this study was to evaluate the current practice of patient preparation for 64-MDCT angiography (CTA) of the coronary arteries. MATERIALS AND METHODS. Sites in the United States that perform 64-MDCT coronary angiography were surveyed by mail in 2006. Information requested included physician specialty; experience level; details about patient preparation, including the use, dose, route, and timing of premedication; and acceptable heart rate and rhythm. A total of 142 surveys were analyzed, with comparison of parameters across specialties (radiology, cardiology, or shared) and experience levels. RESULTS. All facets of the study (premedication, data acquisition, cardiac interpretation) are performed exclusively by radiologists in 49% of sites and by cardiologists in 14%. All sites administer β-blockers. Target heart rate was reported as ≤ 65 beats per minute (bpm) by 89% of responders. Despite most centers aiming for a heart rate of ≤ 65 bpm, the maximum allowable heart rate is > 65 bpm in 80% of centers. Patients with arrhythmia are scanned in at least 25% of sites. Most sites (84%) administer nitroglycerin. Significant differences between specialties were noted for experience levels, timing and route of β-blocker administration, and for target heart rate. The likelihood of scanning in the setting of arrhythmia and β-blocker timing correlated with experience levels. CONCLUSION. These 64-MDCT coronary artery data from 2006 reveal consensus for a range of patient preparation parameters. Use of β-blockers and nitroglycerin is routine, and the target heart rate is usually ≤ 65 bpm. However, differences were noted for β-blocker protocols and acceptable heart rate and rhythm, and some differences in practice are associated with experience level and specialty.