CT angiography with cardiac MRI: non-invasive functional and anatomical assessment for the etiology in newly diagnosed heart failure.

Exclusion of ischemia is important in patients with newly diagnosed systolic heart failure (HF). We prospectively compared standard-of-care invasive catheter angiography (iCA) and echocardiography to a novel non-invasive strategy of both Coronary Computed Tomographic Angiography (CCTA) and Cardiovascular MRI (CMR) to determine the etiology of myocardial dysfunction Prospective data were collected from consecutive patients referred for iCA to investigate echocardiographically-confirmed new onset HF. CMR (1.5T GE) and dual source CCTA were performed within 2-7 days of iCA. Results were blinded and separately analyzed by expert readers. 426 coronary segments from 28 prospectively enrolled patients were analyzed by CCTA and quantitative iCA. The per-patient sensitivity and specificity of CCTA was 100% and 90%, respectively, negative predictive value (NPV) 100%, positive predictive value (PPV) 78%. Mean ejection fraction by CMR was 24%. Presence of ischemic-type LGE on CMR conferred a 67% sensitivity, 100% specificity, 90% NPV and 100% PPV. Combining CCTA with CMR conferred 100% specificity, 100% sensitivity, 100% PPV and 100% NPV for detection or exclusion of coronary disease. In patients with negative CCTA all invasive angiograms could have been avoided. In addition, two patients with no ischemic LGE by CMR had severe coronary disease on both CCTA and iCA, indicating global hibernation. This is a noteworthy finding in contrast to previous reports which suggested that absence of LGE rules out significant CAD. CCTA with CMR in newly-diagnosed HF enables non-invasive assessment of coronary artery disease, the severity and etiology of myocardial dysfunction and defines suitability for revascularization. Absence of ischemic-type LGE at CMR does not exclude CAD as a cause of LV dysfunction. A first-line strategy of functional and anatomic imaging with CMR and CCTA appears appropriate in newly diagnosed HF.

Cardiac MRI is superior to gated blood pool imaging in the assessment of left ventricular function in patients post-cardiac transplantation.

BACKGROUND: Gated Blood Pool Imaging (GBPI) has low inter-test variability compared to echocardiography, and is often used when accurate repeated measurements of left ventricular ejection fraction are required such as in the surveillance of post-transplant patients. The aim of this study was to determine if cardiac MRI (CMR) could replace Gated Blood Pool Imaging for annual assessment of left ventricular (LV) function in the surveillance of patients post-cardiac transplantation. METHODS: Forty-nine patients at various stages of post-cardiac transplantation presenting for annual review underwent LV functional assessment with GBPI and CMR. LV ejection fractions (EF) obtained from the two methods were compared and limits of agreement determined. RESULTS: The mean EF (plus and minus two standard deviations) was 58.3+/-18% for GBPI and 57.6+/-18% for CMR. The two methods were found to provide clinically equivalent results. CONCLUSIONS: Assessment of LVEF with CMR offers comparable values to GBPI in post-heart transplant patients. However, CMR also allows quantitative volumetric analysis of ventricular volumes and assessment of wall motion and valvular function. As is now accepted in native heart assessment, CMR should be considered the "gold standard" for post-transplant volumetric and functional evaluation. CMR offers information over-and-above traditional imaging modalities.