Appropriateness and utilization of cardiac CT: Implications for development of future criteria

Abstract

Background

The cardiac CT (CCT) appropriateness criteria (AC) were jointly published by multiple societies to ensure effective utilization of CCT. We sought to determine how these criteria apply to CCT scans performed at a tertiary-care hospital.

Methods and Results

Data were collected from medical records and interviews of 267 consecutive patients referred for CCT. Two physicians designated exam indication as appropriate, inappropriate, or uncertain as per AC, or “not known” if not listed in AC. CCT exam indication was appropriate in 47%, inappropriate in 9%, uncertain in 15%, and not known in 29%. The most common appropriate indication was evaluation of CAD in symptomatic patients with equivocal stress test, whereas the most common inappropriate referral was evaluation of asymptomatic patients with low pretest probability of CAD. Most exams (69%) were for evaluation of CAD, with the remaining exams performed to evaluate other elements of cardiac structure or function. Exams for these non-CAD indications were more likely to be appropriate and less likely to have an undetermined (uncertain or not known) level of appropriateness than those for CAD indications. There was no difference in exam appropriateness whether ordered by cardiologists or internists, but providers who completed training >25 years ago ordered fewer appropriate and more inappropriate exams than younger providers.

Conclusions

In applying the AC to a large academic medical center, few CCT exams were inappropriate; however, many patients referred for CCT, particularly for evaluation of CAD, had an indication for which the level of appropriateness remained undetermined. Given the rapid adoption of CCT, these results emphasize the need to refine current criteria for appropriate utilization.

Appendix 1

Exam Indications not included in 2006 AC (N = 78):

• Preoperative evaluation for CAD for cardiac surgery

• Detection of CAD in symptomatic patient with low pretest probability of CAD

• Detection of CAD in symptomatic patient with negative stress test

• Detection of CAD in symptomatic patient with mildly positive stress test

• Evaluation of left atrial appendage watchman device

• Post-pulmonary vein ablation, concern for pulmonary vein stenosis

• After invasive angiography to further evaluate a vessel unable to be visualized well on cath

• Monitoring after repair of ascending aortic aneurysm

• Chest pain syndrome, high pretest probability, invasive angiography not clinically appropriate

• Chest pain syndrome, moderate/severe ischemia on stress test, invasive angiography not clinically appropriate

• Asymptomatic, equivocal stress test

• Asymptomatic, mildly positive stress test