Coronary risk equivalence of diabetes assessed by SPECT-MPI.

BACKGROUND: Several publications and guidelines designate diabetes mellitus (DM) as a coronary artery disease (CAD) risk equivalent. The aim of this investigation was to examine DM cardiac risk equivalence from the perspective of stress SPECT myocardial perfusion imaging (MPI). METHODS AND RESULTS: We examined cardiovascular outcomes (cardiac death or nonfatal MI) of 17,499 patients referred for stress SPECT-MPI. Patients were stratified into four categories: non-DM without CAD, non-DM with CAD, DM without CAD, and DM with CAD, and normal or abnormal perfusion. Cardiac events occurred in 872 (5%), with event-free survival best among non-DM without CAD, worst in DM with CAD, and intermediate in DM without CAD, and non-DM with CAD. After multivariate adjustment, risk remained comparable between DM without CAD and non-DM with CAD [AHR 1.0 (95% CI 0.84-1.28), P =0.74]. Annualized event rates for normal subjects were 1.4% and 1.6% for non-DM with CAD and DM without CAD, respectively (P = 0.48) and 3.5% (P = 0.95) for both abnormal groups. After multivariate adjustment, outcomes were comparable within normal [AHR 1.4 (95% CI 0.98-1.96) P = 0.06] and abnormal [AHR 1.1 (95% CI 0.83-1.50) P = 0.49] MPI. CONCLUSIONS: Diabetic patients without CAD have comparable risk of cardiovascular events as non-diabetic patients with CAD after stratification by MPI results. These findings support diabetes as a CAD equivalent and suggest that MPI provides additional prognostic information in such patients.

Characterization of Primary Mitral Regurgitation With Flail Leaflet and/or Wall-Impinging Flow.

BACKGROUND: Echocardiography guidelines note that a flail leaflet is a specific criterion for severe mitral regurgitation (MR) and that regurgitant severity is underestimated in wall-impinging jets (Coanda effect). Both findings are often considered to be pathognomonic of severe MR. OBJECTIVES: In this study, the authors sought to determine the association of flail leaflet and Coanda effect with MR severity quantified by means of cardiac magnetic resonance (CMR). METHODS: The authors enrolled 158 consecutive patients with primary MR according to echocardiography and CMR. The presence of a flail leaflet or Coanda was determined for each patient. CMR regurgitant volume (RV) and regurgitant fraction (RF) were quantified for all patients. RESULTS: There were 55 patients (35%) with a flail leaflet, 52 (33%) with Coanda, and 22 (14%) with a flail leaflet and Coanda. The mean CMR mitral RV and RF progressively increased in patients without a Coanda or flail, a Coanda, a flail, or a Coanda and a flail (RV: 28 ± 21 mL vs 43 ± 23 mL vs 58 ± 29 mL vs 64 ± 25 mL [P < 0.001]; RF: 25% ± 16% vs 34% ± 14% vs 41% ± 12% vs 45% ± 12% [P < 0.001]). With the use of CMR RV, 35%, 46%, and 59% of patients had severe MR with the presence of a Coanda, flail leaflet, or both, respectively. With the use of CMR RF, 25%, 31%, and 40% of patients had severe MR with the presence of a Coanda, flail leaflet, or both, respectively. CONCLUSIONS: While the presence of a flail leaflet and Coanda effect on echocardiography are associated with higher regurgitant volumes and fractions, they are frequently not associated with severe MR as assessed by means of CMR. (Comparison Study of Echocardiography and Cardiovascular Magnetic Resonance Imaging in the Assessment of Mitral and Aortic Regurgitation; NCT04038879).