MONTREAL — Patients with systemic lupus erythematosus demonstrated significantly more perfusion abnormalities on gated scintigraphy scans, compared with well-matched controls, in a small pilot study.
The observed differences may represent early manifestations of cardiomyopathy or silent diffuse myocardial ischemia, Dr. Scott Yoder and colleagues at the University of Rochester (N.Y.) Medical Center reported in a poster at the annual meeting of the American Society of Nuclear Cardiology.
Although several studies have highlighted the utility of gated single photon emission CT (SPECT) scans for the diagnosis of coronary artery disease (CAD) in SLE patients, no specific recommendations have been formulated. Dr. Yoder advocates routine cardiac screening of all lupus patients, and repeat scans roughly every 6 months for any patient with identified CAD to track the progression and severity of the heart disease, as well as disease modification for SLE and treatment of underlying heart disease.
“Especially if they have evidence of heart disease on their initial screening, then every time they have an active flare of their SLE you should probably look to see if they have any worsening of their heart disease,” he said.
Lupus is associated with a two- to fourfold increased risk for coronary artery disease (CAD), and is typically difficult to diagnose because patients don't have classic symptoms and tend to present late with heart failure or some other myocardial injury, Dr. Yoder said in an interview.
The study included 15 SLE patients and 15 controls who were randomly selected from the center's patient database, and matched for age (55 years), gender (90% female), and coronary risk factors such as hypercholesterolemia (80%), hypertension (80%), tobacco use (33%), and family history of CAD (80%). All patients underwent gated SPECT scans, plus either exercise using the Bruce or modified Bruce protocols, or pharmacologic stress testing using dobutamine or adenosine.
Patients with SLE had significantly worse end-systolic volume indices (45 mL/m
Nonsignificant differences also were noted in end-diastolic volume indices (84 mL/m
The study was prompted by a case in which gated-SPECT imaging was used to risk-stratify a 35-year-old male who came to the clinic with active lupus and chest pain, and was found to have significant stress and resting perfusion defects and inducible ischemia in the anterior wall. Aggressive treatment for SLE and cardiac risk factors with prednisone, mycophenolate, aspirin, and atorvastatin resulted in significant regression of the ischemia at 1 year. His ejection fraction recovered from 23% to 47%, and stress-induced cavity dilation of the left ventricle improved from 1.68 to 1.25.
SPECT imaging shows below normal perfusion at rest (top left) and stress-induced ischemia (top right) in an SLE patient with chest pain. SLE and CAD treatment improved resting perfusion (lower left) with no evidence of stress-induced ischemia (lower right). Photos courtesy Dr. Scott Yoder
