RESUMEN
BACKGROUND: Determination of myocardial blood flow (MBF) with MRI is usually performed with dynamic contrast enhanced imaging (MBFDCE ). MBF can also be determined from coronary sinus blood flow (MBFCS ), which has the advantage of being a noncontrast technique. However, comparative studies of MBFDCE and MBFCS in large cohorts are lacking. PURPOSE: To compare MBFCS and MBFDCE in a large cohort. STUDY TYPE: Prospective, sequence-comparison study. POPULATION: 147 patients with type 2 diabetes mellitus (age: 56+/-12 years; 106 male; diabetes duration: 12.9+/-8.1 years), and 25 age-matched controls. FIELD STRENGTH/SEQUENCES: 1.5 Tesla scanner. Saturation recovery sequence for MBFDCE vs. phase-contrast gradient-echo pulse sequence (free-breathing) for MBFCS . ASSESSMENT: MBFDCE and MBFCS were determined at rest and during coronary dilatation achieved by administration of adenosine at 140 µg/kg/min. Myocardial perfusion reserve (MPR) was calculated as the stress/rest ratio of MBF values. Coronary sinus flow was determined twice in the same imaging session for repeatability assessment. STATISTICAL TESTS: Agreement between MBFDCE and MBFCS was assessed with Bland and Altman's technique. Repeatability was determined from single-rater random intraclass and repeatability coefficients. RESULTS: Rest and stress flows, including both MBFDCE and MBFCS values, ranged from 33 to 146 mL/min/100 g and 92 to 501 mL/min/100 g, respectively. Intraclass and repeatability coefficients for MBFCS were 0.95 (CI 0.90; 0.95) and 5 mL/min/100 g. In Bland-Altman analysis, mean bias at rest was -1.1 mL/min/100 g (CI -3.1; 0.9) with limits of agreement of -27 and 24.8 mL/min/100 g. Mean bias at stress was 6.3 mL/min/100 g (CI -1.1; 14.1) with limits of agreement of -86.9 and 99.9. Mean bias of MPR was 0.11 (CI: -0.02; 0.23) with limits of agreement of -1.43 and 1.64. CONCLUSION: MBF may be determined from coronary sinus blood flow, with acceptable bias, but relatively large limits of agreement, against the reference of MBFDCE . LEVEL OF EVIDENCE: 1 TECHNICAL EFFICACY STAGE: 2.
Asunto(s)
Seno Coronario , Diabetes Mellitus Tipo 2 , Imagen de Perfusión Miocárdica , Adulto , Anciano , Humanos , Masculino , Persona de Mediana Edad , Circulación Coronaria/fisiología , Seno Coronario/diagnóstico por imagen , Diabetes Mellitus Tipo 2/diagnóstico por imagen , Imagen por Resonancia Magnética/métodos , Imagen de Perfusión Miocárdica/métodos , Estudios Prospectivos , FemeninoRESUMEN
AIMS: Coronary microvascular disease (CMD) is a known complication in type 2 diabetes mellitus (T2DM). We examined the relationship between diabetic complications, left ventricular (LV) function and structure and myocardial perfusion reserve (MPR) as indicators of CMD in patients with T2DM and control subjects. METHODS AND RESULTS: This was a cross-sectional study of 193 patients with T2DM and 25 controls subjects. Patients were grouped as uncomplicated diabetes (n = 71) and diabetes with complications (albuminuria, retinopathy, and autonomic neuropathy). LV structure, function, adenosine stress, and rest myocardial perfusion were evaluated by cardiovascular magnetic resonance. Echocardiography was used to evaluate diastolic function. Patients with uncomplicated T2DM did not have significantly different LV mass and E/e* but decreased MPR (3.8 ± 1.0 vs. 5.1 ± 1.5, P < 0.05) compared with controls. T2DM patients with albuminuria and retinopathy had decreased MPR (albuminuria: 2.4 ± 0.9 and retinopathy 2.6 ± 0.7 vs. 3.8 ± 1.0, P < 0.05 for both) compared with uncomplicated T2DM patients, along with significantly higher LV mass (149 ± 39 and 147 ± 40 vs. 126 ± 33 g, P < 0.05) and E/e* (8.3 ± 2.8 and 8.1 ± 2.2 vs. 7.0 ± 2.5, P < 0.05). When entered in a multiple regression model, reduced MPR was associated with increasing E/e* and albuminuria and retinopathy were associated with reduced MPR. CONCLUSIONS: Patients with uncomplicated T2DM have reduced MPR compared with control subjects, despite equivalent LV mass and E/e*. T2DM patients with albuminuria or retinopathy have reduced MPR and increased LV mass and E/e* compared with patients with uncomplicated T2DM. E/e* and MPR are significantly associated after adjustment for age, hypertension, and LV mass, suggesting a link between CMD and cardiac diastolic function. CLINICAL TRIAL REGISTRATION: https://www.clinicaltrials.org. Unique identifier: NCT02684331.