Previous studies have found that less than 40% of patients with stable chest pain undergoing invasive coronary angiography had obstructive coronary heart disease. Recent randomized clinical trials have shown that the use of computed tomography angiography (CTA) was beneficial in the initial assessment of these patients, and a new study presented at the American College of Cardiology’s Cardiovascular Summit lends credibility to this strategy, stating that CT was associated with a higher likelihood of revascularization compared to other imaging methods or no tests.
Stable angina pectoris is a type of chest discomfort that occurs when the heart muscle needs more oxygen than usual – such as during stress, physical activity, or cold weather – but does not receive it, often due to blocked coronary arteries. Patients with stable angina pectoris are often treated with guideline-directed medical therapy and lifestyle modifications, but may also require coronary revascularization to restore adequate blood flow and alleviate their symptoms.
If a patient currently presents with angina pectoris-suspected symptoms to their primary care physician or cardiologist, they are often referred for further testing.
Markus Scherer, MD, Director of Heart CT and Structural Heart Imaging at Atrium Health-Sanger Heart & Vascular Institute and lead author of the study
Between October 2022 and June 2023, researchers at the Atrium Health-Sanger Heart & Vascular Institute in Charlotte, North Carolina, examined 786 patients who had not previously been diagnosed with coronary heart disease and underwent elective invasive coronary angiography (ICA) to evaluate suspicion of angina pectoris. The initial assessment strategies before ICA were: no non-invasive tests with direct referral to ICA (44%), stress echocardiography (3%), stress myocardial perfusion imaging (15%), stress MRI (2%), and coronary CTA (36%). The study cohort had an average age of 66 years and consisted of 63% men, 37% women, 81% white, 13% black, 1% Asian, 1% Hispanic, and 1% other.
The researchers compared the rates of subsequent revascularization between patients whose initial assessment was coronary CTA versus stress tests or clinical assessment (no tests). The „CT first“ strategy was associated with subsequent revascularization in 62% of patients, compared to 34% with the combination of other modalities or direct referral to ICA.
In the 2021 AHA/ACC Guideline for the Evaluation and Diagnosis of Chest Pain, either non-invasive functional imaging or coronary CTA is suggested as the initial test, with no preference indicated for one over the other.
According to the researchers, there are a variety of reasons why health systems currently do not employ a CT-first approach, including the availability of high-quality CT scanners, availability of qualified interpreters of cardiac CT, and challenges in transitioning to a newer approach after decades of established patterns (e.g. stress tests). Furthermore, a CT-first approach is recommended primarily for patients with undetected coronary heart disease and may not be applicable to all, as some patient factors can compromise the accuracy and benefits of coronary CTA.
„While care must be individualized, transitioning to a ‚CT first‘ strategy for providers of cardiovascular care for patients with unknown or undetected coronary heart disease should be a high priority,“ said Scherer. „The non-invasive approach is associated with lower risk and lower cost than a diagnostic catheterization and provides information for the CT approach – but not for stress tests – on the absence, presence, and extent of coronary atherosclerosis and whether they are high or not.“ Risk plaques and vessel obstructions, contributing to streamlining patient management and risk mitigation.“
As coronary CTA is more cost-effective than nuclear myocardial perfusion imaging and ICA, Scherer states that a CT-first approach results in direct cost savings for patients and payers. From a health system perspective, the most economically efficient assessment approach gains importance in the transition to a value-based health system.
The authors of the study state that the study demonstrates the „real“ credibility of randomized studies showing similar benefits to a „CT first“ approach, and should promote increased adoption of this strategy for the assessment of patients with chest pain and no documented history of coronary artery disease.
„Cath labs are an intensive care environment for capital and personnel. Using them for their maximum potential for treating diseases rather than diagnosing them brings the highest yield of these resources to the health system,“ said Scherer.
The full results of the study and other studies will be presented at the ACC Cardiovascular Summit 2024 in Washington from February 1 to 3, 2024. The ACC Cardiovascular Summit 2024 will explore innovative strategies and new trends in cardiovascular care and assess operational efficiency to improve the effectiveness of the CV service line and to adopt customizable approaches that support economic sustainability.
American College of Cardiology