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Current guidelines recommend an implantable cardioverter-defibrillator (ICD) according to the left ventricular ejection fraction (LVEF). However, they do not mandate volumetric LVEF assessment. We sought to determine whether volumetric LVEF measurement using cardiovascular magnetic resonance imaging (CMR-LVEF) is superior to conventional LVEF measurement using 2-dimensional transthoracic echocardiography (Echo-LVEF) for risk stratifying patients referred for primary prevention ICD. Patients who underwent primary prevention ICD implantation at our institution and had undergone preimplantation CMR-LVEF from November 2001 to February 2011 were identified. Volumetric CMR-LVEF was determined from cine short-axis data sets. CMR-LVEF and Echo-LVEF were extracted from the clinical reports. The end point was appropriate ICD discharge (shock and/or antitachycardia pacing). Of 48 patients, appropriate ICD discharge occurred in 9 (19%) within 29 – 25 months (range 1 to 99, median 20). All patients met the Echo-LVEF criteria for ICD implantation; however 25% (95% confidence interval 13% to 37%) did not meet the CMR-LVEF criteria. None (0%) of these latter patients had received an appropriate ICD discharge. Using CMR-LVEF ≤30% as a threshold for ICD eligibility, 19 patients (40%) with a qualifying Echo-LVEF would not have been referred for ICD, and none (0%) received an ICD discharge. For primary prevention ICD implantation, volumetric CMR-LVEF might be superior to clinical Echo-LVEF for risk stratification and can identify a large minority of subjects in whom ICD implantation can be safely avoided. In conclusion, if confirmed by larger prospective series, volumetric methods such as CMR should be considered a superior “gatekeeper” for the identification of patients likely to benefit from primary prevention ICD implantation.

Purpose: To develop an improved chemical shift-based water-fat separation sequence using a water-selective inversion pulse for inversion recovery 3D contrast-enhanced cardiac magnetic resonance imaging (MRI). Materials and Methods: In inversion recovery sequences the fat signal is substantially reduced due to the application of a nonselective inversion pulse. Therefore, for simultaneous visualization of water, fat, and myocardial enhancement in inversion recovery-based sequences such as late gadolinium enhancement imaging, two separate scans are used. To overcome this, the nonselective inversion pulse is replaced with a water-selective inversion pulse. Imaging was performed in phantoms, nine healthy subjects, and nine patients with suspected arrhythmogenic right ventricular cardiomyopathy plus one patient for tumor/mass imaging. In patients, images with conventional turbo-spin echo (TSE) with and without fat saturation were acquired prior to contrast injection for fat assessment. Subjective image scores (1 = poor, 4 = excellent) were used for image assessment. Results: Phantom experiments showed a fat signal-to-noise ratio (SNR) increase between 1.7 to 5.9 times for inversion times of 150 and 300 msec, respectively. The water-selective inversion pulse retains the fat signal in contrast-enhanced cardiac MR, allowing improved visualization of fat in the water-fat separated images of healthy subjects with a score of 3.7 ± 0.6. Patient images acquired with the proposed sequence were scored higher when compared with a TSE sequence (3.5 ± 0.7 vs. 2.2 ± 0.5, P < 0.05). Conclusion: The water-selective inversion pulse retains the fat signal in inversion recovery-based contrast-enhanced cardiac MR, allowing simultaneous visualization of water and fat. J. Magn. Reson. Imaging 2013;37:484–490. © 2012 Wiley Periodicals, Inc.

Background Chemical shift based water-fat separation methods can be used to reconstruct simultaneous fat and water images, thereby improving the sensitivity of fat detection using a positive fat contrast. The presence of fatty infiltration is a hallmark pathological feature of arrhythmogenic right ventricular cardiomyopathy (ARVC). Furthermore, the presence of fatty infiltration in chronic myocardial infarction has been demonstrated recently [1,2]. To assess for both presence of scar using late gadolinium enhancement (LGE) and fat, two separate scans are needed. In this study, we propose an improved inversion recovery based water-fat separation sequence in which the fat signal is retained by the application of a spectrally selective water inversion pulse, thereby eliminating the need for two separate scans.

Background Women with signs and symptoms of ischemia but no obstructive coronary artery disease (CAD), often have coronary microvascular dysfunction (CMD) evidenced by the Women’s Ischemia Syndrome Evaluation (WISE) studies [1,2]. CMD is associated with higher risk of adverse cardiac events including heart failure compared to healthy women [1,2]. Elevated native T1 values are known to be suggestive of myocardial fibrosis. We hypothesized that the native myocardial T1 would be abnormally elevated indicating fibrosis in WISE subjects with CMD.

Background In conventional prospective respiratory navigator (NAV) acquisitions, 40-60% of the acquired data are discarded resulting in low efficiency and long scan times [1,2]. Compressed-sensing Motion Compensation (CosMo) has a shorter fixed scan time by acquiring the full inner k-space and estimating the NAV-rejected outer k-space lines [3]. Respiratory motion will mainly manifest itself as phase variation in the acquired k-space data. We sought to determine if the addition of the magnitude of the rejected k-space lines as a constraint in image reconstruction will improve the performance of CosMo.