Prognostic value of noninvasive combined anatomic/functional assessment by cardiac CT in patients with suspected coronary artery disease - Comparison with invasive coronary angiography and nuclear myocardial perfusion imaging for the five-year-follow up of the CORE320 multicenter study

Abstract

Background: Few data exist on long-term outcome in patients undergoing combined coronary CT angiography (CTA) and myocardial CT perfusion imaging (CTP) as well as invasive coronary angiography (ICA) and single photon emission tomography (SPECT).

Methods: At 16 centers, 381 patients were followed for major adverse cardiac events (MACE) for the CORE320 study. All patients underwent coronary CTA, CTP, and SPECT before ICA within 60 days. Prognostic performance according binary results (normal/abnormal) was assessed by 5-year major cardiovascular events (MACE) free survival and area under the receiver-operating-characteristic curve (AUC).

Results: Follow up beyond 2-years was available in 323 patients. MACE-free survival rate was greater among patients with normal combined CTA-CTP findings compared to ICA-SPECT: 85 vs. 80% (95% confidence interval [CI] for difference 0.1, 11.3) though event-free survival time was similar (4.54 vs. 4.37 years, 95% CI for difference: -0.03, 0.36). Abnormal results by combined CTA-CTP was associated with 3.83 years event-free survival vs. 3.66 years after abnormal combined ICA-SPECT (95% CI for difference: -0.05, 0.39). Predicting MACE by AUC also was similar: 65 vs. 65 (difference 0.1; 95% CI -4.6, 4.9). When MACE was restricted to cardiovascular death, myocardial infarction, or stroke, AUC for CTA-CTP was 71 vs. 60 by ICA-SPECT (difference 11.2; 95% CI -1.0, 19.7).

Conclusions: Combined CTA-CTP evaluation yields at least equal 5-year prognostic information as combined ICA-SPECT assessment in patients presenting with suspected coronary artery disease. Noninvasive cardiac CT assessment may eliminate the need for diagnostic cardiac catheterization in many patients.

Clinical trial registration: NCT00934037.

Keywords: CT angiography; Coronary artery disease; Coronary atherosclerosis; Coronary heart disease; Coronary imaging; Myocardial perfusion imaging.

Fig. 1.

Flow of study patients and follow-up, An overview of patient flow and follow up is provided. Of 381 patients, 379 had complete imaging information and at least 2-year follow up. Of these, 56 patients were lost to follow up beyond 2 years while 323 had additional data collected.

Fig. 2.

Kaplan-Meier curves for 5-year event-free survival, Kaplan-Meier curves are shown for 5-year event-free survival in 323 patients according to the results (abnormal [+]; normal [−]) of combined CTA-CTP and ICA-SPECT assessment of hemodynamically significant coronary heart disease). Differences between the test combinations were not statistically significant. Abbreviations: MACE: major adverse cardiovascular event; CTA: computed tomography angiography; CTP: computed tomography perfusion; ICA: invasive coronary angiography; SPECT: single-photon-emission tomography.

Fig. 3.

Receiver operating characteristic curves for MACE events. Receiver operating characteristic (ROC) curves are shown for identifying patients who suffered MACE at 5-year follow up. Data were modelled as continuous variables with the Leaman score included in each model. Panel A shows the ROC curves for combined CTA-CTP and ICA-SPECT for predicting all MACE. Panel B shows the curves for combined CTA-CTP and ICA-SPECT for predicting “hard” events, defined as myocardial infarction, death, or stroke. Differences between the test combinations were not statistically significant. Abbreviations: MACE: major adverse cardiovascular event; ROC: receiver operating characteristic; CTA: computed tomography angiography; CTP: computed tomography perfusion; ICA: invasive coronary angiography; SPECT: single-photon-emission tomography.