For the evaluation of patients with suspected CAD, the costs of single-photo emission CT were significantly lower than that of PET or coronary CTA, according to new data from the SPARC registry.
At 2 years, patients who underwent PET had higher costs and mortality compared with SPECT, and patients who underwent coronary CTA had higher costs and similar mortality compared with SPECT, researchers reported.
For this economic analysis, Mark A. Hlatky, MD, and colleagues used data from the SPARC registry of 1,703 participants who underwent CTA (n=590), PET (n=548) or SPECT (n=565) for suspected CAD at 41 centers from May 2006 to April 2008. All patients were followed for 2 years, and resource use, medical costs for CAD and clinical outcomes were documented.
Mark A. Hlatky
Costs after each procedure
Two-year costs were highest among patients who received PET ($6,647 per patient; 95% CI, $5,896-$7,397), intermediate in the CTA group ($4,909 per patient; 95% CI, $4,378-$5,440) and lowest after SPECT ($3,965 per patient; 95% CI, $3,520-$4,411). After multivariable adjustment to account for differences in baseline characteristics, CTA recipients had 15% higher costs than the SPECT group (P<.01) and PET costs were 22% higher than SPECT (P<.0001).
Mortality rates at 2 years were 0.7% after CTA, 1.6% after SPECT and 5.5% after PET. Patients in the CTA group lost a mean 0.08 years of life based on life-expectancy tables, while the SPECT group lost 0.23 years and the PET group lost 0.76 years. After adjustment for baseline characteristics, no significant difference in survival was observed between PET and either CTA or SPECT, according to the study findings (P=.07 for both).
Although the incremental cost-effectiveness ratio for CTA compared with SPECT was $11,700 per life-year added, bootstrap replications created uncertainty, the researchers wrote, noting that in 13% of bootstrap replications, CTA had higher costs and higher mortality than SPECT. However, patients undergoing PET had higher costs and higher mortality than those undergoing SPECT in 98% of bootstrap replications.
“The significantly higher costs among patients undergoing CTA or PET were primarily due to higher rates of subsequent invasive cardiac procedures, because there was little difference in initial costs of testing,” Hlatky, from Stanford University School of Medicine, and colleagues wrote. They added that further study is needed to evaluate newer iterations of CTA, PET and SPECT, as well as novel technologies such as fractional flow reserve.
Superior quality uncertain
According to Todd C. Villines, MD, of Walter Reed National Military Medical Center, Bethesda, Md., and James K. Min, MD, of New York-Presbyterian Hospital, New York, it is unclear whether the findings indicate a “superior diagnostic performance of CTA and PET compared with SPECT,” with a higher rate of “true positive” patients referred for invasive coronary angiography and/or revascularization.
“It remains a vexing proposition to conduct long-term or even intermediate-term investigations … that represent a static moment in time for technologies whose development effectively outpaces the study,” they wrote in a related editorial.
For more information:
Hlatky MA. J Am Coll Cardiol. 2014;63:1002-1008.
Villines TC. J Am Coll Cardiol. 2014;63:1009-1010.
Disclosure: The researchers and Villines report no relevant financial disclosures. Min reports serving on the medical advisory board for and receiving speakers honoraria and research support from GE Healthcare.