ImportanceAlthough atherosclerosis represents the primary driver of coronary artery disease, evaluation and treatment approaches have historically relied upon indirect markers of atherosclerosis th... Show moreImportanceAlthough atherosclerosis represents the primary driver of coronary artery disease, evaluation and treatment approaches have historically relied upon indirect markers of atherosclerosis that include surrogates (cholesterol), signs (angina), and sequelae (ischemia) of atherosclerosis. Direct quantification and characterization of atherosclerosis may encourage a precision heart care paradigm that improves diagnosis, risk stratification, therapeutic decision-making, and longitudinal disease tracking in a personalized fashion.ObservationsThe American College of Cardiology Innovations in Prevention Working Group introduce the Atherosclerosis Treatment Algorithms that personalize medical interventions based upon atherosclerosis findings from coronary computed tomography angiography (CTA) and cardiovascular risk factors. Through integration of coronary CTA-based atherosclerosis evaluation, clinical practice guidelines, and contemporary randomized controlled trial evidence, the Atherosclerosis Treatment Algorithms leverage patient-specific atherosclerosis burden and progression as primary targets for therapeutic intervention. After defining stages of atherosclerosis severity by coronary CTA, Atherosclerosis Treatment Algorithms are described for worsening stages of atherosclerosis for patients with lipid disorders, diabetes, hypertension, obesity, and tobacco use. The authors anticipate a rapid pace of research in the field, and conclude by providing perspectives on future needs that may improve efforts to optimize precision prevention of coronary artery disease. Importantly, the Atherosclerosis Treatment Algorithms are not endorsed by the American College of Cardiology, and should not be interpreted as a statement of American College of Cardiology policy.Conclusions and RelevanceWe describe a precision heart care approach that emphasizes atherosclerosis as the primary disease target for evaluation and treatment. To our knowledge, this is the first proposal to use coronary atherosclerosis burden and progression to personalize therapy selection and therapy changes, respectively. Show less
Background: Atherosclerotic plaque characterization by coronary computed tomography angiography (CCTA) enables quantification of coronary artery disease (CAD) burden and type, which has been... Show moreBackground: Atherosclerotic plaque characterization by coronary computed tomography angiography (CCTA) enables quantification of coronary artery disease (CAD) burden and type, which has been demonstrated as the strongest discriminant of future risk of major adverse cardiac events (MACE). To date, there are no clinically useful thresholds to assist with understanding a patient's disease burden and guide diagnosis and management, as there exists with coronary artery calcium (CAC) scoring. The purpose of this manuscript is to establish clinically relevant plaque stages and thresholds based on evidence from invasive angiographic stenosis (ICA) and fractional flow reserve (FFR) data. Methods: 303 patients underwent CCTA prior to ICA and FFR for an AHA/ACC clinical indication. Quantitative computed tomography (QCT) was performed for total plaque volume (TPV, mm(3)) and percent atheroma volume (PAV, %). We segmented atherosclerosis by composition for low-density non-calcified plaque (LD-NCP), non-calcified plaque (NCP), and calcified plaque (CP). ICAs were evaluated by quantitative coronary angiography (QCA) for all coronary segments for % diameter stenosis. The relationship of atherosclerotic plaque burden and composition by QCT to ICA stenosis extent and severity by QCA and presence of ischemia by FFR was assessed to develop 4 distinct disease stages. Results: The mean age of the patients was 64.4 & PLUSMN; 10.2 years; 71% male. At the 50% QCA stenosis threshold, QCT revealed a mean PAV of 9.7 (& PLUSMN;8.2)% and TPV of 436 (& PLUSMN;444.9)mm(3) for those with non-obstructive CAD; PAV of 11.7 (& PLUSMN;8.0)% and TPV of 549.3 (& PLUSMN;408.3) mm(3) for 1 vessel disease (1VD), PAV of 17.8 (& PLUSMN;9.8)% and TPV of 838.9 (& PLUSMN;550.7) mm(3) for 2VD, and PAV of 19.2 (& PLUSMN;8.2)% and TPV of 799.9 (& PLUSMN;357.4) mm(3) for 3VD/left main disease (LMD). Non-ischemic patients (FFR > 0.8) had a mean PAV of 9.2 (& PLUSMN;7.3) % and TPV of 422.9 (& PLUSMN;387.9 mm(3)) while patients with at least one vessel ischemia (FFR & LE;0.8) had a PAV of 15.2 (& PLUSMN;9.5)% and TPV of 694.6 (& PLUSMN;485.1). Definition of plaque stage thresholds of 0, 250, 750 mm(3) and 0, 5, and 15% PAV resulted in 4 clinically distinct stages in which patients with no, non-obstructive, single VD and multi-vessel disease were optimally distributed. Conclusion: Atherosclerotic plaque burden by QCT is related to stenosis severity and extent as well as ischemia. We propose staging of CAD atherosclerotic plaque burden using the following definitions: Stage 0 (Normal, 0% PAV, 0 mm(3) TPV), Stage 1 (Mild, > 0-5% PAV or > 0-250 mm(3) TPV), Stage 2 (Moderate, > 5-15% PAV or > 250-750 mm(3) TPV) and Stage 3 (Severe, > 15% PAV or > 750 mm(3) TPV). Show less