The Role of Cardiac Imaging in Clinical Decision-Making

Editor's Note: This is Part One of a three-part series highlighting several of the presentations from the American College of Cardiology’s Annual Scientific Session (ACC.26) that took place in March in New Orleans, Louisiana.

Three trials presented at the American College of Cardiology’s Annual Scientific Session (ACC.26) examined the role of cardiac imaging in clinical decision-making. Two studies used intravascular ultrasound (IVUS) to guide percutaneous coronary intervention (PCI), and the other used coronary computed tomography angiography (CCTA) to measure whether a new drug could slow plaque progression. None of the trials, however, showed significantly improved outcomes in the specific patient populations studied.

“Technologies like IVUS allow us to see the coronaries, plaque, stent apposition, mal-expansion and thrombus in detail, while CCTA is a great noninvasive test for plaque quantification,” says Khalil Kaid, MD, director of Interventional Cardiology at Newark Beth Israel Medical Center (NBIMC)/RWJBarnabas Health. “But what I’m seeing from these studies is that using them does not guarantee a better patient outcome.”

IVUS Guidance 

IVUS-guided PCI was found to be not superior in patients with complex coronary arteries nor in patients with unprotected left-main coronary artery disease (LM-CAD), according to the results of two international, open-label randomized trials presented at ACC.26.

The first, IVUS-CHIP, enrolled 2,020 patients with complex coronary artery lesions. Half received IVUS-guided PCI, while the other half received angiography-guided PCI. Results showed that routine IVUS-guided PCI performed with the use of prespecified stent optimization criteria was not associated with a lower risk of target-vessel failure than angiography-guided PCI alone.¹

The second, the OPTIMAL trial, studied 806 LM-CAD patients, with 401 undergoing IVUS-guided PCI and 405 undergoing angiography-guided PCI. Outcomes showed that the IVUS-guided PCI group showed no additional benefit over angiography-guided PCI with respect to the incidence of stroke, myocardial infarction, revascularization, or death from any cause at a median follow-up of 2.9 years.²

These results, Dr. Kaid suggests, indicate that IVUS may not be appropriate for every case. “Interventionalists who do high-risk PCI or left-main interventions who have been trained on angiography alone may not go to IVUS all the time—maybe in selective cases,” he says. “But for those of us who have trained on IVUS in their fellowship and rely on it more, I think they should continue to use it.”

Dr. Kaid has seen firsthand the benefits of IVUS use in both practice and training at NBIMC, and he expects the use of IVUS to grow irrespective of trial results. “We are, as my mentors used to say, angiographers, but our fellows who use IVUS early in their training have a better sense of sizing and length, and with AI, they can get quick, accurate reads on ultrasounds,” he says. “It’s an excellent tool for fellows as they get accustomed to interpreting anatomy beyond what the angiogram alone can show.”

Olezarsen 

The ESSENCE-TIMI 73b trial showed that olezarsen resulted in significant reductions in triglyceride levels at six months among patients with moderate hypertriglyceridemia and elevated cardiovascular risk.³ At ACC.26, researchers presented the results in a substudy, ESSENCE-CTA, using CCTA measurements at baseline and 12 months after randomization to determine whether olezarsen could reduce noncalcified coronary plaque volume (NCPV). The results showed that olezarsen did not affect NCPV even though the therapy helped participants reduce triglyceride levels by 63.9% and remnant cholesterol by 71.9%.⁴

“The substudy may be negative because of the time,” Dr. Kaid says. “I don’t think 12 months is long enough to see that kind of effect. I think 18 to 24 months would have been a little more appropriate.”

What is clear, Dr. Kaid says, is olezarsen’s effect on reducing triglycerides. “In both groups, there was a little bit of regression, so it’s quantifiable,” he says. “Future studies should show us if triglycerides are truly part of the big picture when it comes to atherosclerosis.”

Despite the neutral findings of all three of these abstracts, Dr. Kaid sees the results as a snapshot in time rather than a verdict on imaging itself. “Imaging is not going away,” he says. “The technology is going to get better, and AI is going to help cardiologists even more in the future.”

References

1. Diletti R, Daemen J, Faurie B, et al; for the IVUS CHIP Investigators. Intravascular ultrasound-guided or angiography-guided complex high-risk PCI. N Engl J Med. Published online March 30. doi:10.1056/NEJMoa2601521

2. Testa L, De la Torre Hernandez JM, De Maria GL, et al. IVUS-guided versus angiography-guided PCI in unprotected left main coronary artery disease. N Engl J Med. Published online March 30. doi:10.1056/NEJMoa2600440

3. Bergmark BA, Marston NA, Prohaska TA, et al; for the ESSENCE–TIMI 73b Investigators. Targeting APOC3 with olezarsen in moderate hypertriglyceridemia. N Engl J Med. Published online Aug. 30, 2025. doi:10.1056/NEJMoa2507227

4. Marston NA, Bergmark BA, Prohaska TA, et al. Effect of APOC3 inhibition with olezarsen on coronary atherosclerosis: ESSENCE–TIMI 73b imaging study. Circulation. Published online March 30. doi:10.1161/CIRCULATIONAHA.126.080012