Normal stress myocardial perfusion imaging has a limited prognostic value in patients with severely reduced renal function: a sub-study of J-ACCESS3

Background: Patients with chronic kidney disease (CKD) have a higher risk of cardiovascular events and death than those without. Coronary artery disease (CAD) in CKD patients is frequently silent. To maximize the effective treatment of cardiovascular disease in patients with CKD, it is important to identify CAD objectively in CKD patients in a noninvasive way as early as possible. Risk stratification is essential for the development of evidence-based strategies for improved patient care in medicine in CKD patients. In general, patients with normal SPECT images had a lower risk of death and hard cardiac events, whereas in patients with abnormal myocardial perfusion, the mortality and hard cardiac event rates became significantly higher. However, the clinical significance of normal SPECT images in CKD patients who might have higher cardiovascular events has not yet been clarified. Therefore, the purpose of this study is to test the hypothesis that a normal myocardial perfusion imaging (MPI) study in chronic kidney disease (CKD) can provide benign prognostic information for the prediction of major cardiovascular events. Results: A multicenter study of Japanese assessment of cardiac events and survival studies by quantitative gated SPECT (J-ACCESS)-3 registry was a prognostic cohort study involving 62 institutions using stress MPI. All institutions employed certified physicians for examination of CAD, and the patients could participate in a 3-year follow-up. Among J-ACCESS3 subjects, this sub-study included subjects with normal perfusion imaging. The study group consisted of 431 CKD patients (males, 64 %; mean age, 72 ± 11 years) with normal SPECT imaging. All SPECT data in the Digital Images and Communication in Medicine format were processed at the J-ACCESS office (Osaka, Japan). An image interpretation committee objectively evaluated defect scores to achieve objective scoring. The committee consisted of seven collaborative physicians who evaluated digitally the submitted SPECT images in a blinded manner. The committee determined defect scores using summed stress/rest/difference scores (SSS/SRS/SDS) with a 17-segment model, confirming computer generated defect scores ranging from 0 (normal uptake) to 4 (defect). Thresholds for scoring were based on the normal database of the Japanese Society of Nuclear Medicine working group. Based on SPECT image and QGS data, 331 had a summed stress score of 3 or less, a summed difference score of 1 or less and normal cardi