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Background Duchenne Muscular Dystrophy (DMD) is an X-linked recessive disease with an incidence of 1/3500 live male births. Loss of the dystrophin protein leads to progressive muscle degeneration and an absolute genetic risk of developing cardiac disease. Currently there is a lack of a sensitive diagnostic tool to identify cardiac dysfunction in early stages of the disease and standard measures of decreased global function, e.g. ejection fraction (EF), are only detectable when advanced disease is present. We found that myocardial circumferential strain (Ecc, an indicator of local myocardial deformation normalized to its original dimension) can detect occult cardiac disease early in the course of disease despite normal EF, and Ecc magnitude further declines with advancing age and disease progression. DMD associated cardiac disease leads to replacement of normal myocyte with myocardial fibrosis leading to eventual cardiac dysfunction; cardiac magnetic resonance (CMR) has been used to assess for late gadolinium enhancement (LGE, an indicator of myocardial fibrosis) in DMD patients. We sought to determine if Ecc is a predictor of myocardial fibrosis in DMD patients.

Summary A new approach to myocardial first-pass perfusion imaging is presented; this technique, called SSFPP, is based on 3D SSFP sequence whereby magnetization is maintained in constant steady-state, while data acquisition is gated to diastole. This results in high SNR and CNR, and other characteristics that can potentially mitigate dark rim artifacts. The high-blood myocardial contrast of SSFP allows automatic segmentation, which, combined with registration, facilitates image analysis. Background Although introduced in 1990, myocardial first-pass perfusion imaging has not yet become a routine diagnostic tool, primarily because of insufficient image quality, insufficient coverage, and dark rim artifacts (DRA). Current techniques rely on a saturation recovery (SR) preparation for T1 contrast, resulting in poor SNR, low efficiency, and k-space modulation during SR. Further, the post-processing of these images is tedious. In this work, we propose an alternative perfusion imaging technique, called Steady-State First Pass Perfusion (SSFPP). Objective To develop a new 3D first-pass perfusion imaging technique that can potentially address the limitations of current methods. Theory SSFPP is a 3D SSFP sequence in which the magnetization is maintained in constant steady-state while the data acquisition is gated to diastole. The SNR and CNR are similar to those in SSFP cine imaging, allowing the use of automatic segmentation algorithms. Furthermore, the tissue contrast is dependent on T1/T2; serendipitously, this causes blood signal to remain almost constant, whereas the myocardial signal exhibits a nearly linear correlation with contrast agent concentration. Maintenance of steady-state throughout data acquisition avoids k-space modulation, and the elimination of saturation recovery time increases data acquisition efficiency by reducing deadtime. Methods

Background Limb girdle muscular dystrophies (LGMD) are inclusive of 7 autosomal dominant and 14 autosomal recessive disorders featuring progressive muscle weakness and atrophy. Studies of cardiac function have not yet been well-defined in deficiencies of dysferlin (LGMD2B) and fukutin related protein (LGMD2I). In this study of patients with these two forms of limb girdle muscular dystrophy, cardiovascular magnetic resonance (CMR) was used to more specifically define markers of cardiomyopathy including systolic dysfunction, myocardial fibrosis, and diastolic dysfunction. Methods Consecutive patients with genetically-proven LGMD types 2I (n = 7) and 2B (n = 9) and 8 control subjects were enrolled. All subjects underwent cardiac magnetic resonance (CMR) on a standard 1.5 Tesla clinical scanner with cine imaging for left ventricular (LV) volume and ejection fraction (EF) measurement, vector velocity analysis of cine data to calculate myocardial strain, and late post-gadolinium enhancement imaging (LGE) to assess for myocardial fibrosis. Results Sixteen LGMD patients (7 LGMD2I, 9 LGMD2B), and 8 control subjects completed CMR. All but one patient had normal LV size and systolic function; one (type 2I) had severe dilated cardiomyopathy. Of 15 LGMD patients with normal systolic function, LGE imaging revealed focal myocardial fibrosis in 7 (47%). Peak systolic circumferential strain rates were similar in patients vs. controls: εendo was -23.8 ± 8.5vs. -23.9 ± 4.2%, εepi was -11.5 ± 1.7% vs. -10.1 ± 4.2% (p = NS for all). Five of 7 LGE-positive patients had grade I diastolic dysfunction [2I (n = 2), 2B (n = 3)]. that was not present in any LGE-negative patients or controls. Conclusions LGMD2I and LGMD2B generally result in mild structural and functional cardiac abnormalities, though severe dilated cardiomyopathy may occur. Long-term studies are warranted to evaluate the prognostic significance of subclinical fibrosis detected by CMR in these patients.

The clinical presentation of beriberi can be quite varied. In the extreme form, profound cardiovascular involvement leads to circulatory collapse and death. This case report is of a 72 year-old male who was admitted to the Neurology inpatient ward with progressive bilateral lower extremity weakness and parasthesia. He subsequently developed pulmonary edema and high output cardiac failure requiring intubation and blood pressure support. With the constellation of peripheral neuropathy, encephalopathy, ophthalmoplegia, unexplained heart failure, and lactic acidosis, thiamine deficiency was suspected. He was empirically initiated on thiamine replacement therapy and his thiamine level pre-therapy was found to be 23 nmol/L (Normal: 80-150 nmol/L), consistent with the diagnosis of beriberi. Cardiovascular magnetic resonance (CMR) showed severe left ventricular systolic dysfunction, markedly increased myocardial T2, and minimal late gadolinium enhancement (LGE). After 5 days of daily 100 mg IV thiamine and supportive care, the hypotension resolved and the patient was extubated and was released from the hospital 3 weeks later. Our case shows via CMR profound myocardial edema associated with wet beriberi.

Introduction Bariatric surgery has been shown to provide significant and durable weight loss in extremely obese adults and its application and outcomes in the adolescent population is the main focus of several on-going prospective studies in the Unites States and elsewhere. Pre-surgical cardiovascular (CV) screening in the adolescent population is warranted as extreme obesity is an independent predictor of numerous forms of cardiac disease and mortality and is often complicated by practical and technological issues.

Methods A large kindred who exhibit a mixed phenotype of HCM, dilated cardiomypopathy (DCM) and sudden cardiac death segregating in an autosomal dominant inheritance were evaluated. Six individuals from 2 generations the proband, her husband, and their 4 offspring, one son and three daughters, ages 20, 25, 23 and 18 years of age, respectively were followed. The proband had a known history of DCM; offspring had normal cardiac morphology by baseline CMR examination with delayed post-gadolinium enhancement (DME). This cohort was followed with yearly cardiac imaging to detect initial phenotypic expression. Direct DNA sequencing of the coding regions and splice sites of the MYH7, MYBPC3, TNNT2, TNNI3, and TPM1 genes was performed on all 6 members of this nuclear family. Results Genotyping in this selected family revealed a novel heterozygous 2105T>A (I702N) missense mutation in exon 19 of the MYH7 gene in the proband, the son and one daughter. Three unaffected family members tested negative for the mutation. The phenotype in the proband and her 18 year-old daughter progressed to exhibit DCM with evidence of early fibrotic changes by DME. The son progressed to asymmetrical septal hypertrophy, not initially apparent by echocardiography, consistent with early stage HCM. The 3 other members of the family had normal CMR examinations. Figure 1.