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Objectives: The authors determined if E-point septal separation (EPSS) as measured by junior emergency physicians (EPs) correlated with visual estimation of left ventricle ejection fraction (LVEF) by senior EPs and cardiologists in acutely dyspneic patients presenting to an adult emergency department (ED).Methods: Acutely dyspneic patients were enrolled in a prospective, observational study. EPSS was measured using bedside ultrasonography by junior EPs (PGY 3 and PGY 4 residents) with variable ultrasound experience. M-mode measurements of EPSS were recorded in the parasternal long-axis orientation and were calculated during diastole by measuring distance from the tip of the anterior mitral valve leaflet to the septal wall. LVEF was visually estimated at the bedside by emergency medicine (EM) ultrasound fellows and an EM ultrasound fellowship-trained attending physician and was subsequently visually estimated by two cardiologists reviewing video clips obtained by the junior EPs. The correlation between EPSS and visually estimated LVEF was calculated.Results: Of the 58 patients, the median age was 63 years (range = 28 to 90 years) and 66% were women. Interobserver reliability between EPs and cardiologists for the visual estimation of LVEF was excellent (j = 0.75). The correlation between measurements of EPSS by junior EPs and visual estimations of LVEF by the senior EPs was q = )0.844 (p < 0.001).Conclusions: In this study, junior EPs were able to obtain measurements of EPSS that correlated closely with visual estimates of LVEF by clinicians with extensive point-of-care and comprehensive echocardiography experience.

Paravalvular regurgitation is an uncommon but important complication, usually following valve replacement surgery. Early recognition and management are important for reoperations are associated with high morbidity and mortality rates. Presently, little data are available on this topic. The authors review the subject.

Abstract-Emerging evidence illustrates the importance of the positive transcription elongation factor (P-TEF)b in control of global RNA synthesis, which constitutes a major feature of the compensatory response to diverse hypertrophic stimuli in cardiomyocytes. P-TEFb complex, composed of cyclin T and cdk9, is critical for elongation of nascent RNA chains via phosphorylation of the carboxyl-terminal domain of RNA polymerase (Pol) II. We and others have shown that the activity of P-TEFb is inhibited by its association with cardiac lineage protein (CLP)-1, the mouse homolog of human HEXIM1, in various physiological and pathological conditions. To investigate the mechanism of control of P-TEFb activity by CLP-1 in cardiac hypertrophy, we used a transgenic mouse model of hypertrophy caused by overexpression of calcineurin in the heart. We observed that the level of CLP-1 associated with P-TEFb was reduced markedly in hypertrophic hearts. We also generated bigenic mice (MHC-cyclin T1/CLP-1) by crossing MHC-cyclin T1 transgenic mice with CLP-1 heterozygote. The bigenic mice exhibit enhanced susceptibility to hypertrophy that is accompanied with an increase in cdk9 activity via an increase in serine 2 phosphorylation of carboxyl-terminal domain and an increase in GLUT1/GLUT4 ratio. These mice have compensated systolic function without evidence of fibrosis and reduced lifespan. These data suggest that the reduced level of CLP-1 introduced in the background of elevated levels of cyclin T1 elevates derepression of P-TEFb activity and emphasizes the importance of the role of CLP-1 in the mechanism governing compensatory hypertrophy in cardiomyocytes.

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With increasing legalization, marijuana has become the most commonly abused substance in the United States. Together with the introduction of more potent marijuana products over the years, more adverse events are being reported and clinically characterized. Delta-9-tetrahydrocannabinol (THC) is the active psychotropic component of marijuana, which acts mainly on G-protein cannabinoid receptors CB1 and CB2. Multiple isolated cases of arrhythmias associated with marijuana use have been published. In this manuscript we conduct a scoping study of a total of 27 cases of arrhythmia associated with marijuana. Most cases were reported in young males (81%) with a mean age of 28 ± 10.6 years. Atrial fibrillation (26%) and ventricular fibrillation (22%) were the most common arrhythmias reported. Brugada pattern was reported in 19% of the patients. Marijuana associated arrhythmia resulted in a high mortality rate of 11 %. While the exact mechanisms of arrhythmias associated with marijuana are not clear, several hypothesis have been introduced including the effect of marijuana on cardiac ion channels as well as its effects on the central nervous system. In this paper we discuss the possible mechanisms of marijuana induced arrhythmia citing the evidence available to-date.

CVD is a major cause of morbidity and mortality in pediatric patients with CKD. It is unclear whether vascular abnormalities in these patients are reversible, and if transplantation portends salutary effects on arterial function. We compared FMD, PWV, AI75, and CIMT in 15 dialysis (D), 14 transplant patients (T), and 15 controls (C), and their associations with cardiovascular risk factors. There was stepwise lower FMD (p < 0.001), higher AI75 (p < 0.001), higher PWV (p = 0.01), and higher CIMT SDS for age (p = 0.03) and height (p = 0.006) in the D group than T and C groups. FMD, PWV, and CIMT were unrelated to dialysis duration or time from transplantation. On multivariate analysis, group status was independently associated with FMD (β = 3.15, p = 0.002), AI75 (β = -5.95, p = 0.01), PWV (β = -0.57, p = 0.07) and CIMT (β = -0.02, p = 0.04) and CIMT SDS for height (β = -0.541, p = 0.009). FMD is lower and AI75, PWV and CIMT are higher in pediatric patients maintained on D than T/C. T patients have similar AI75, PWV and CIMT to C although FMD remains reduced. These findings suggest that transplantation stabilizes or improves CKD associated arteriopathy.

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