Impaired Myocardial Flow Reserve on 82Rubidium Positron Emission Computed Tomography in Patients with Systemic Sclerosis
Abstract
Objective To investigate the association between Raynaud phenomenon (RP) and coronary microvascular dysfunction, we measured myocardial flow reserve (MFR) using positron emission tomography/computed tomography (PET/CT) in primary and secondary RP patients and controls.
Methods RP patients, patient controls and healthy participants who underwent dynamic reststress 82-Rubidium PET/CT were studied. Differences in heart rate-blood pressure product corrected MFR and clinical predictors of reduced MFR (< 2.0) were determined.
Results 49 RP patients (80% female, 65 ± 11 years): 11 primary RP, 18 systemic sclerosis (SSc) and 20 other autoimmune diseases (AID) (n=6 systemic lupus erythematosus, n=6 rheumatoid arthritis, n=4 overlap syndrome, n=2 Sjogren's syndrome, n=2 inflammatory arthritis), 49 matched patients without RP or AID (78% female, 64 ± 13 years) and 14 healthy participants (50% female, 35 ± 5 years) were studied. Primary RP patients, matched patient controls and healthy participants had comparable MFR. SSc-RP patients had significantly reduced MFR (1.62 ± 0.32) compared to matched patient controls (p=0.03, 2.06 ± 0.61) and to healthy participants (p=0.01, 2.22 ± 0.44). In multivariable logistic regression, SSc was an independent predictor of reduced MFR. We identified a correlation between time since AID diagnosis and MFR (r= -0.37; 95% CI: -0.61 to -0.09; p=0.01).
Conclusion Our findings suggest that only secondary, not primary, RP is associated with reduced MFR, and that SSc-RP patients have reduced MFR compared to primary RP and other