Relationship between cardiac symptoms, myocardial perfusion defects and coronary angiography findings in systemic lupus erythematosus.

Coronary angiography is generally regarded as the 'gold standard' test for diagnosing coronary artery disease (CAD). We sought to determine the relationship between cardiac symptoms and findings of coronary angiography and myocardial perfusion scintigraphy (MPS) in patients with systemic lupus erythematosus (SLE). Medical records of all SLE patients who underwent coronary angiography while attending our clinic over 24 years were reviewed, noting the indication for the test and its findings. Among patients who had MPS within 6 months prior to coronary angiography, a contingency table was used to rate the agreement between the two tests. Among the 35 patients who underwent coronary angiography, 31 had the test to investigate cardiac symptoms. Among the symptomatic patients, 17 (55%) had an abnormal angiogram with one or more plaques, while 14 (45%) had normal angiograms. All four asymptomatic patients had normal angiograms. Compared to those with normal angiograms, patients with abnormal angiograms had a higher mean number of cardiovascular risk factors per patient (1.6 ± 1.4 vs. 0.6 ± 1.0, p = 0.02). Twenty-four patients had both angiography and MPS. Overall, the agreement between angiography and MPS was poor (κ = 0, p = 0.0008), with 14 (58.3%) patients having perfusion defects and normal angiograms. A proportion of SLE patients with cardiac symptoms do not have plaques on coronary angiography. Overall there is poor agreement between the findings of coronary angiography and MPS in SLE, suggesting mechanisms of ischemia other than plaques.