Calcium Scoring Pinpoints Stenoses in Asymptomatic Diabetes
For diabetes patients with no cardiovascular symptoms despite certain risk factors, incorporating coronary calcium scoring into a silent myocardial ischemia screening algorithm may be an effective and cost-conscious strategy that avoids missed coronary stenoses suitable for revascularization, results of a recent study suggest.
Zero patients in need of revascularization were missed in a risk stratification model in which screening for silent myocardial ischemia (SMI) was done only for patients with peripheral artery disease, severe nephropathy, or a high coronary artery calcium (CAC) score, according to investigator Paul Valensi, MD.
In practical terms, that means stress myocardial scintigraphy to detect SMI could be reserved for patients with evidence of target organ damage or a CAC score of 100 or higher, according to Dr. Valensi, head of the department of endocrinology, diabetology, and nutrition at Jean Verdier Hospital in Bondy, France.
“The strategy appears to be a good compromise, and the most cost effective strategy,” Dr. Valensi said in a presentation of the results at the virtual annual scientific sessions of the American Diabetes Association.
Utility of CAC Scoring in Diabetes
This algorithm proposed by Dr. Valensi and colleagues is a “reasonable” approach to guide risk stratification in asymptomatic diabetes patients, said Matthew J. Budoff, MD, professor of medicine and director of cardiac CT at Harbor-UCLA Medical Center in Torrance, Calif.
“Calcium scoring could certainly help you identify those patients (at increased risk) as a first-line test, because if their calcium score is zero, their chance of having obstructive disease is probably either zero or very close to zero,” Dr. Budoff said in an interview.
Using CAC scores to assess cardiovascular risk in asymptomatic adults with diabetes was supported by 2010 guidelines from the American College of Cardiology and the American Heart Association, Dr. Budoff said, while 2019 guidelines from the European Society of Cardiology (ESC) describe CAC score combined with CT as a potential risk modifier in the evaluation of certain asymptomatic patients with diabetes.
“We are starting to see that we might be able to understand diabetes better and the cardiovascular implications by understanding how much plaque (patients) have at the time that we see them,” Dr. Budoff said in a presentation on use of CAC scans he gave earlier at the virtual ADA meeting.
In the interview, Dr. Budoff also noted that CAC scores may be particularly useful for guiding use of statins, PCSK9 (proprotein convertase subtilisin kexin 9) inhibitors, or other treatments in patients with diabetes: “There are a lot of therapies that we can apply, if we knew somebody was at higher risk, that would potentially help them avoid a heart attack, stroke, or cardiovascular death,” he said.
CAC Scoring and Coronary Artery Stenoses
Although about 20% of patients with type 2 diabetes have SMI, screening for it is “debated,” according to Dr. Valensi.