Cardiac Imaging in Suspected Coronary Artery Disease

Unnecessary Angiography Suspected CAD
Unnecessary Angiography Suspected CAD
Two imaging studies found that less invasive screening procedures reduced unnecessary angiographies in patients with coronary heart disease or suspected coronary artery disease.

Less invasive screening procedures reduced the number of unnecessary angiograms without putting patients at greater risk for adverse events, according to results from 2 imaging studies.1,2

CONSERVE (COronary Computed Tomographic ANgiography for SElective Cardiac Catheterization Relation to CardioVascular Outcomes and Economics) and CE-MARC 2 (Clinical Evaluation of Magnetic Resonance Imaging in Coronary Heart Disease 2) evaluated patients with coronary heart disease (CHD) or suspected coronary artery disease (CAD) who had rates of major adverse cardiovascular events (MACE) similar to patients who underwent angiography, and were screened using coronary computed tomography angiography (CCTA) and cardiovascular magnetic resonance (CMR).

Deborah Kwon, MD, a cardiologist in the section of Cardiovascular Imaging at the Robert and Suzanne Tomsich Department of Cardiovascular Medicine of the Sydell and Arnold Miller Family Heart & Vascular Institute in Cleveland reviewed the results for Cardiology Advisor. These results, if verified in longer-term follow-up studies, might provide a clear benefit for both the patient while reducing medical costs, she said.

“These 2 studies are very interesting and could potentially shift the way cardiologists practice in terms of evaluating patients with chest pain and suspected CAD,” she said.

Results from the CONSERVE trial were presented during the 2016 European Society of Cardiology congress in Rome. The investigators found that selective CCTA was associated with an 86% reduction in invasive coronary angiography (ICA) and no differences MACE compared with a direct invasive angiography approach. Both approaches were associated with 4.6% rate of MACE at 12months (P =.99), but per-patient costs for CCTA were significantly lower ($2883 vs $6031). Patients with indications for invasive angiography were assigned to direct ICA (n=719) or selective ICA with CCTA (n=784).

“Our study observed lower rates of invasive procedure, which were also associated with cost savings,” lead researcher Hyuk-Jae Chang, MD, PhD, with the Yonsei University College of Medicine in Seoul, said in a press release.3 “The message from this trial is that, if we use CCTA as a gatekeeper to the catheterization lab in stable symptomatic patients with suspected CAD, we’ll reduce costs with sufficient safety.”Dr Chang also found that CCTA was associated with a 41% reduction in revascularization, a result he called “clinically important.”

“CT guided strategy may uncouple the diagnosis—treatment cascade of ICA which promote excess revascularization and subsequently expose patients to non-negligible risk related to invasive procedure,” he said.

In the randomized, 3-parallel group CE-MARC 2 clinical trial, John P. Greenwood and fellow researchers set out to determine if CMR)–guided care was superior to National Institute for Health and Care Excellence (NICE) guidelines–directed care and myocardial perfusion scintigraphy (MPS)–guided care for reducing unnecessary angiography.

From November 2012 to November 2015, patients with CHD were recruited from 6 hospitals in the UK and randomly assigned to NICE guidelines–directed care (n=240), CMR (n=481), or MPS (n=481).

At 12 months of follow-up, 28.8% of patients in the NICE group had unnecessary angiography, compared with 7.5% of the CMR group and 7.1% of the MPS group. The adjusted odds ratio for unnecessary angiography was 0.21 (95% CI, 0.12- 0.34; P <.001) in the CMR vs NICE groups and 1.27 (95% CI, 0.79- 2.03; P =.32) for CMR group vs MPS.

MACE adjusted hazard ratios were 1.37 (95% CI, 0.52-3.57; P =.52) in the CMR vs NICE groups and 0.95 (95% CI, 0.46-1.95; P =.88) in the CMR vs MPS groups (see table). Rates for cardiovascular death and myocardial infarction were also similar between the 3 groups, 1.3% for NICE compared with 1.0% for CMR and 0.8% for MPS.

“In patients with suspected angina, investigation by CMR resulted in a lower probability of unnecessary angiography within 12 months than NICE guideline–directed care, with no statistically significant difference between CMR and MPS strategies,” the researchers wrote. “There were no statistically significant differences in MACE rates at 12 months after randomization.”


Rate (%)

Annualized rate (%)










NICE=National Institute for Health and Care Excellence; CMR=cardiovascular magnetic resonance; MPS=myocardial perfusion scintigraphy.

“The government is encouraging us to perform fewer imaging tests because the medical cost of doing all these additional tests isn’t economically efficient,” Dr Kwon said. “These 2 studies are saying that rather than going straight to invasive testing, these noninvasive imaging modalities may be a better way to risk-stratify these patients, sparing them a potentially invasive procedure and saving downstream costs as well.”

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Disclosures: CE-MARC 2 investigators reported the following disclosures: Dr Berry reported holding research agreements with Siemens Healthcare and St. Jude Medical. Dr Bucciarelli-Ducci reported consulting for Circle Cardiovascular Imaging. CONSERVE investigators reported no financial conflicts. The trial was funded by an investigator-initiated unrestricted grant from GE Healthcare and Severance Hospital of Yonsei University.


  1. Chang HK, Szymonifka J, Gebow D, et al. The CONSERVE trial. Presented at the European Society of Cardiology Congress 2016. August 27-31, 2016; Rome, Italy.
  2. Greenwood JP, Ripley DP, Berry C, et al; for the CE-MARC 2 Investigators. Effect of care guided by cardiovascular magnetic resonance, myocardial perfusion scintigraphy, or NICE Guidelines on subsequent unnecessary angiography rates. The CE-MARC 2 randomized clinical trial. JAMA. 2016;316(10):1051-1060. doi:10.1001/jama.2016.12680.
  3. The CONSERVE trial: Noninvasive imaging can guide more selective invasive coronary angiography [press release]. Rome, Italy: European Society of Cardiology; August 29, 2016. Accessed September 28, 2016.