Advanced CT Scan Revolutionizes Artery Treatment, Cutting Invasive Procedures

Coronary CT angiography (CTA) is used by doctors to diagnose narrowed or blocked arteries in the heart. A CTAThe examination assigns a rating ranging from mild (0-1) to moderate (2-3) to severe (4-5). Patients with scores above 3 usually need medical treatment and may benefit from stents or surgeries (revascularization) to restore blood flow to the heart.

“CTA indicates the level of blockage in a vessel,” explained Mangun Kaur Randhawa, M.D., a post-doctoral research fellow in the Department of Radiology at Massachusetts General Hospital (MGH) in Boston. “However, the extent of blockage does not always accurately predict the amount of blood flow in the vessel.”

Doctors have traditionally relied on an invasive procedure known as invasive  Coronary angiography is used to visualize blood vessels, and newer invasive tests like fractional flow reserve (FFR) are used to identify and evaluate significant blockages in the vessels. A relatively recent non-invasive alternative, CT-FFR, models a patient’s coronary blood flow using CTA images of the heart, AI algorithms, and/or computational fluid dynamics.

Dr. Randhawa’s research team conducted a retrospective study to assess the impact of selective use of CT-FFR on clinical outcomes. The study included patients who had undergone coronary CTA at MGH between August 2020 and August 2021.

During the study period, 3,098 patients underwent coronaryCT-FFR analysis was performed on 284 out of 2,985 patients after 113 coronary bypass grafting patients were excluded. 9.7% of the remaining patients were referred for CT-FFR analysis, with most referrals being for patients with scores of 3 or above. Specifically, 73.5% of patients with a score of 3 underwent CT-FFR analysis. According to Dr. Randhawa, this analysis is particularly beneficial for patients with moderate narrowing or blockage of the arteries, as it helps to determine who would benefit from invasive testing and revascularization procedures.The use of FFR assists us in pinpointing and choosing those patients who are most likely to experience positive outcomes. Among the 284 patients, 160 (56.3%) received a negative CT-FFR result of > 0.80, 88 patients (30.9%) had a clearly positive (abnormal) result of ≤ 0.75, and the remaining 36 patients (12.6%) fell within the borderline result range of 0.76-0.80. Patients with significant narrowing/blockages on coronary CTA who underwent CT-FFR had lower rates of invasive coronary angiography (25.5% vs. 74.5%) and subsequent percutaneous coronary intervention (21.1% vs. 78.9%) than patients who were not referred for a CT-FFR. The CT-FFR helps us in identifying patients who have a higher likelihood of benefiting.We aim to maximize the benefits of non-invasive procedures and delay stent or surgical treatment for patients who may not need it,” explained Brian B. Ghoshhajra, M.D., M.B.A., senior author and associate chair for operations and academic chief of cardiovascular imaging at MGH. “CT-FFR improves the accuracy of CT scans, and we have found that it is most beneficial when used selectively.”

Dr. Ghoshhajra also noted that the CT-FFR analysis was successful for the majority of patients, even in cases with challenging factors such as irregular heart rates and obesity.

<p”By objectively measuring coronary artery flow with CT-FFR, we can avoid unnecessary procedures for patients.The speaker suggested that there is a need for further investigation and treatment, not only addressing what is visible to the naked eye but also what is supported by physiology,” he said.

The study’s findings demonstrate the usefulness of CT-FFR in clinical practice, when used selectively, indicating its potential to reduce the need for invasive procedures in patients with significant coronary artery narrowing or blockages without compromising safety.