SNOWMASS, COLO. – When Spencer B. King III, MD, shared his thoughts about the future of interventional cardiology at the Annual Cardiovascular Conference at Snowmass sponsored by the American College of Cardiology, he felt compelled to offer a cautionary note about his past accuracy as a prognosticator.
It was way back at a poster session during the 1976 annual meeting of the American Heart Association in Miami Beach that he first met Andreas Gruentzig, MD, the father of percutaneous coronary intervention (PCI), who was presenting his initial revolutionary work on what he called “coronary transluminal angioplasty” in dogs.
“I looked at the poster and told him it would never work,” recalled Dr. King, professor emeritus of medicine at Emory University in Atlanta.
He soon changed his mind, however, because, to great acclaim, Dr. Gruentzig performed his successful first in-human coronary angioplasty the next year.
He noted that the Snowmass conference has played a significant role in the development of interventional cardiology in the United States. Dr. Gruentzig attended the conference in 1980, and Dr. King and others took that opportunity to persuade him to leave the bureaucratic confines of Zurich and join him at Emory later that year. The two cardiologists worked closely thereafter, refining angioplasty and conducting clinical trials until Dr. Gruentzig’s death in an airplane crash in Georgia in 1985 at age 46 years.
Turning to the future, Dr. King addressed a number of recent developments in interventional cardiology and rated their chances of significantly improving outcomes in patients with stable ischemic heart disease. He graded the innovations’ potential with use of a four-bar schema, akin to the WiFi signal power rating on a cell phone.
Noninvasive diagnostics to assess anatomy and physiology
“I think coronary CT angiography [CTA] will become the new diagnostic angiogram,” he predicted. “CTA has gotten much better. Outside the United States, in Europe and particularly in Japan and increasingly in China, CTA is becoming extremely common.”
Dr. King cited a recent multicenter study of blinded heart team treatment decision making on the basis of either CTA or conventional invasive angiography in 223 patients with left main or triple-vessel coronary artery disease (CAD). The level of agreement was impressively high: Coronary artery bypass grafting (CABG) was recommended for 28% of patients on the basis of CTA and 26% with conventional angiography, which suggests the feasibility of treatment decision making based solely on noninvasive imaging, history, and clinical examination (Eur Heart J. 2018 Nov 1;39:3689-98).
“The other thing I like about the potential for noninvasive imaging to guide our interventions is that it may [replace] the diagnostic angiogram, which has largely become extinct,” the cardiologist continued. “If you think about it, patients are referred for an angiogram, and as far as informed consent is concerned, the patient is told to pack his bags, go off to some other city, get in the cath lab, and take the family because of what they might do to you. They might put stents in you, they might operate on you. We don’t have any idea because we don’t know what you have. And the patient has to buy into this. With CTA, the potential is there for people to actually know what you’re going to do to them before you do it.”
Coronary artery calcium scoring for primary risk assessment has taken on a prominent role in the latest practice guidelines. “I think it’s mostly helpful in getting people out of the system because they don’t have any calcium,” in Dr. King’s view.
PET and MRI will remain secondary noninvasive technologies. They will be used mostly to diagnose microvascular disease, but that’s information that doesn’t have much influence on whether interventional procedures are performed.
Overall, he gave noninvasive diagnostic tools high marks for their potential to improve outcomes in patients with stable ischemic heart disease.
“I give it a pretty robust three bars. Maybe you could give it four,” he said.