Stanford UniversitySchool of Medicine, Stanford, California.
JAMA.2011 Nov 16;306(19):2128-36.
Non-invasive coronary computed tomography angiography (CTA) hasevolved into an accepted diagnostic test for symptomatic patient withlow/intermediate clinical suspicion for coronary artery disease (CAD). However,its impact on clinical management is incompletely established.
In the current paper, the authors compare utilization and spendingassociated with functional (stress testing) and anatomical (CCTA) noninvasivecardiac testing in a large Medicare population. Specifically, in a retrospective,observational cohort study the authors analyzed claims data from a 20% randomsample of 2005-2008 Medicare fee-for-service beneficiaries 66 years or olderwith no claims for CAD in the preceding year, who received non-emergent,noninvasive testing for CAD (n = 282 830). Main outcome measureswere cardiac catheterization, coronary revascularization, acute myocardialinfarction, all-cause mortality, and total and CAD-related Medicare spendingover 180 days of follow-up.
The authors report that compared with stress myocardial perfusionscintigraphy (MPS), CCTA was associated with an increased likelihood ofsubsequent cardiac catheterization (22.9% vs 12.1%; adjusted odds ratio [AOR],2.19 [95% CI, 2.08 to 2.32]; P < .001), percutaneous coronaryintervention (7.8% vs 3.4%; AOR, 2.49 [2.28 to 2.72]; P < .001),and coronary artery bypass graft surgery (3.7% vs 1.3%; AOR, 3.00 [2.63 to3.41]; P < .001). CCTA was also associated with higher totalhealth care spending ($4200 [$3193 to $5267]; P < .001), which wasalmost entirely attributable to payments for any claims for CAD ($4007 [$3256to $4835]; P < .001). Compared with MPS, there was lower associatedspending with stress echocardiography (−$4981 [−$4991 to −$4969];P < .001) and exercise electrocardiography (−$7449 [−$7452 to−$7444]; P < .001). At 180 days, CCTA was associated with asimilar likelihood of all-cause mortality (1.05% vs 1.28%; AOR, 1.11 [0.88 to1.38]; P = .32) and a slightly lower likelihood of hospitalizationfor acute myocardial infarction (0.19% vs 0.43%; AOR, 0.60 [0.37 to 0.98];P = .04).
The authors summarize that medicare beneficiaries who underwent CCTAin a non-acute setting were more likely to undergo subsequent invasive cardiacprocedures and have higher CAD-related spending than patients who underwentstress testing.
The results are interesting and will add to the discussion aboutmost appropriate use of coronary CTA. The reader should consider other resultswith different conclusions, including:
- Nielsen LH, Markenvard J, Jensen JM, Mickley H, Øvrehus KA,Nørgaard BL.
Int J Cardiovasc Imaging. 2011 Jul;27(6):813-23.