SCCT 2021 Expert Consensus Document on Coronary Computed Tomographic Angiography: A Report of the Society of Cardiovascular Computed Tomography

TY - JOUR

T1 - SCCT 2021 Expert Consensus Document on Coronary Computed Tomographic Angiography

T2 - A Report of the Society of Cardiovascular Computed Tomography

AU - Narula, Jagat

AU - Chandrashekhar, Y.

AU - Ahmadi, Amir

AU - Abbara, Suhny

AU - Berman, Daniel S.

AU - Blankstein, Ron

AU - Leipsic, Jonathon

AU - Newby, David

AU - Nicol, Edward D.

AU - Nieman, Koen

AU - Shaw, Leslee

AU - Villines, Todd C.

AU - Williams, Michelle

AU - Hecht, Harvey S.

N1 - Funding Information: Ron Blankstein- Research support from Amgen Inc, and Astellas Inc. Funding Information: In addition to the presence and severity of coronary artery stenosis, CTA can provide additional information on plaque burden and adverse coronary artery plaque characteristics. Semi-quantitative assessment of plaque burden such as the CT-Leaman score21 or segment involvement score can provide additional stratification of patients with non-obstructive coronary artery disease that is an independent predictor of subsequent prognosis. In the Partners registry, among 3242 patients evaluated with CTA, patients with non-obstructive plaque involving at least 4 segments had the same risk of hard cardiovascular events as those who had obstructive CAD22 Moreover, treatment of such individuals with extensive plaque was associated with a reduction in cardiovascular events22 which is supported by other data showing that plaques can be stabilized with various therapies. Quantitative assessment of plaque characteristics is also associated with subsequent outcomes in multiple studies. 23?25 In a study looking at serial CTAs, the percent atheroma volume (PAV) at baseline was the strongest predictor of progression of non-obstructive disease to obstructive lesions.25 The non calcified component of plaque is important: while not different from patients with low vs. high clinical risk (based on number of risk factors), high volume of noncalcified plaque is one of the strongest parameters for predicting ACS in patients with extensive CAD.24 Not surprisingly, an increased total, non-calcified or low-density plaque volume is associated with a significant increase in cardiac mortality in >5 years follow-up, independent of the segment involvement score.23 Similar data are seen in high risk groups like asymptomatic diabetic subjects.26 A composite inclusion of plaque volume, location and composition, might be advantageous for prognostication.27Following CTA-detection of obstructive CAD, there have been concerns regarding an increasing rate of downstream invasive coronary angiography (ICA). Early reports noted higher rates of post-CTA use of ICA but more recent data support a more selective referral of patients to ICA following index CTA testing. In a report from the CONFIRM registry (n = 15,207 symptomatic patients), follow-up rates of ICA were low over 3 years of follow-up for patients with normal (2.5%) and mild CAD (8.3%), defined as a stenosis 1?49%.71 By comparison, for patients with obstructive CAD, use of ICA occurred promptly within 3 months of follow-up and occurred in 44%, 53%, and 69%, respectively of patients with 1-, 2-, and 3-vessel CAD. Overall, in the PROMISE trial, a relatively low rate of ICA use was reported for patients randomized to CTA (12%) as compared to the functional testing (8%) arms of the trial.57 Evidence is not available to judge the appropriateness of ICA use, as post-CTA use of stress testing or additional documentation of ischemia prior to ICA referral is not available. A synthesis of this evidence supports a relatively low rate of referral to ICA, notably for those patients without any obstructive CAD.Additional cost analyses are available from the CRESCENT trial whereby referral to exercise electrocardiography was associated with a higher rate of additional diagnostic testing; nearly half of patients in the stress testing arm had induced diagnostic testing procedures as compared to only 1 in 4 in the CTA arm of the CRESCENT trial (p < 0.0001).60 This higher rate of diagnostic testing following exercise electrocardiography was associated with a 16% higher cost of care. Additional cost savings were achieved in the CTA arm of the CRESCENT trial as nearly 42% of this arm had a 0 CAC score and did not undergo follow-up CTA, per the selective testing protocol whereby only those with detectable CAC proceeded to CTA. The randomized trial evidence supports the conclusion that costs associated with a CTA strategy are similar to those following stress testing, with only minimal differences through 2?3 years of follow-up.Ultimately the combination of the strongest negative predictive value of CTA, compared to the gold standard (at both 50% and 70% thresholds), and a comparable positive predictive value compared with alternative modalities, in conjunction with being the least costly investigation, demonstrated that CTA was the most cost-effective first line investigation at all levels of disease prevalence (25%, 45% and 75%). NICE predicted that uptake of their guidelines would save the NHS up to $20 million dollars annually. Early validation of NICE's 2016 approach against the SCOT-HEART dataset strongly supported the use of CTA as the first line investigation.159The above data support the accuracy of CTA for the non-invasive evaluation of the presence, extent, and severity of CAD. Importantly, when compared to functional testing techniques, the use of CTA is associated with increased use of preventive medical therapies and a significant reduction in the rate of incident myocardial infarction.66,68, 162?164 Review of the data supports a relatively low rate of referral to ICA, notably for those patients without any obstructive CAD, without an increased likelihood of undergoing coronary revascularization in the only long term trial.162 The collective data strongly support the achievement of outcomes by CTA which are at least comparable to functional testing, without increasing costs.

PY - 2021/5/1

Y1 - 2021/5/1

UR - http://www.scopus.com/inward/record.url?scp=85097670178&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=85097670178&partnerID=8YFLogxK

U2 - 10.1016/j.jcct.2020.11.001

DO - 10.1016/j.jcct.2020.11.001

M3 - Article

C2 - 33303384

AN - SCOPUS:85097670178

SN - 1934-5925

VL - 15

SP - 192

EP - 217

JO - Journal of cardiovascular computed tomography

JF - Journal of cardiovascular computed tomography

IS - 3

ER -