Journal of cardiovascular diseases & diagnosis最新文献

Background: The initial systolic blood pressure (SBP) in patients presenting to the hospital with acute heart failure (AHF) informs prognosis, diagnosis, and guides initial treatment. However, over time AHF presentations with elevated SBP appear to have declined. The present study examined whether the frequency of AHF presentations with systolic hypertension (SBP >160 mmHg) declined over a nearly two-decade time interval.

Methods: This study compares four historical, cross-sectional cohorts with AHF who were admitted to tertiary care medical centres in the North-eastern USA in 1995, 2000, 2006, and 2011-13. The main outcome was the proportion of AHF patients presenting with an initial SBP >160 mmHg.

Results: 2,366 patients comprised the study sample. The average age was 77 years, 55% were female, 94% white, and 75% had prior heart failure. In 1995, 34% of AHF patients presented with an initial SBP >160 mmHg compared to 20% in 2011-2013 (p<0.01). Multivariate logistic regression demonstrated reduced odds of presenting with a SBP >160 mmHg in 2006 (0.64, 95% CI 0.42-0.96) and 2011-13 (0.46, 95% CI 0.28-0.74) compared with patients in 1995.

Conclusion: The proportion of patients with AHF and initial SBP >160 mmHg significantly declined over the study time period. There are several potential reasons for this observation and these findings highlight the need for ongoing surveillance of patients with AHF as changing clinical characteristics can impact early treatment decisions.

Purpose: Tricuspid annuloplasty rings are commonly used to cinch an enlarged tricuspid annulus back to its original shape and size in patients with severe functional tricuspid regurgitation. However, the invasive operation is contraindicated for patients at risk for reoperation. Fortunately, transcatheter repair procedures, currently in the development process, are minimally invasive alternatives to current repair techniques. This study aims to determine the species-dependence of cinching force with the potential of informing transcatheter repair design by quantifying the minimum required cinching force necessary to reduce tricuspid regurgitation.

Methods: The cinching force necessary to reduce the septal-lateral diameter of a dilated annuls was quantified and compared in ten ovine hearts and nine porcine hearts. Additionally, a deparaffinization protocol and Verhoeff-Van Gieson stain were used to compare the microscopic structure of tissue samples at different stages of the experimental procedure in the two species.

Results: The maximum annulus dilation observed for the porcine was 11.2%, and the maximum cinching force was 0.40 ± 0.12 N. As previously demonstrated, ovine hearts yielded a maximum annulus dilation and cinching force of 8.82% and 0.38 ± 0.09 N respectively. Histological stains revealed no gross tissue differences between ovine and porcine septal or free wall tissues.

Conclusion: The cinching force was not species dependent between ovine and porcine models. This study is an essential first step for determining which animal model should be utilized for the development of transcatheter devices.

Alcoholic cardiomyopathy represents one of the main clinical complications in chronic alcoholics. This pathology contrasts the seemingly beneficial effect of small doses of alcohol on the cardiovascular system. Studies carried out in liver cells exposed acutely or chronically to varying doses of EtOH indicate that intrahepatic alcohol metabolism results in a major loss of cellular Mg²⁺. To investigate whether EtOH administration also induced Mg²⁺ extrusion in cardiac cells, H9C2 cells were exposed to varying doses of EtOH for short- or ling-term periods of time. The results indicate that H9C2 cells exposed to EtOH doses higher than 0.1% (v/v, or 15 mM) extruded Mg²⁺ into the extracellular medium on a time- and dose-dependent manner. Consistent with the involvement of cyP4502E1 in metabolizing EtOH, administration of chloro-methiazole (CMZ) as an inhibitor of the cytochrome prevented EtOH-induced Mg²⁺ loss to a large extent. EtOH-induced Mg²⁺ extrusion was also prevented by the administration of di-thio-treitol (DTT) and n-acetyl-cysteine (NAC), two agents that prevent the negative effects of ROS formation and free radicals generation associated with EtOH metabolism by cyP4502E1. Taken together, our data indicate that Mg²⁺ extrusion also occur in cardiac cells exposed to EtOH as a result of alcohol metabolism by cyP4502E1 and associated free radical formation. Interestingly, Mg²⁺ extrusion only occurs at doses of EtOH higher than 0.1% administered for an extended period of time. The significance of Mg²⁺ extrusion for the onset of alcoholic cardiomyopathy remains to be elucidated.

Unlike zebrafish and newt hearts, mammalian hearts have limited capacity to regenerate. Upon injury or disease, the adult mammalian hearts form a fibrotic scar. Recently, it was shown that neonatal mouse hearts can regenerate similarly to adult zebrafish hearts. However, this capacity quickly decreases after postnatal day 7 (P7). Understanding the molecular mechanisms underlying neonatal heart regeneration might lead to therapeutic approaches for regenerating adult mammalian hearts. In this study, we utilized an inducible transgenic mouse model to determine the effects of FGF10 growth factor over expression on neonatal mouse heart regeneration/repair. Over expression of FGF10 in myocardium enhanced the expansion of Wt1 positive epicardial cells at 21 days after heart injury through increased proliferation. However, this expansion of epicardial cells did not lead to increased epithelial-to-mesenchymal transition or affect fibroblast formation or fibrosis, as seen by vimentin expression, after heart injury. Furthermore, neither continuous nor transient expression of FGF10 did not affect scar thickness or length after heart injury in neonatal hearts. Our results suggest that FGF10 can regulate epicardial cell expansion of neonatal mouse hearts after injury; however, FGF10 alone is not sufficient to cause beneficial effects on heart repair.

The PediBooster external cardiac compression device is a minimally invasive, non-blood contacting Biventricular Assist Device (BiVAD) intended for pediatric use. It is being developed as a palliative therapy for acute Postcardiotomy Shock (PCS). The PediBooster extracardiac wrap is pneumatically actuated to circumferentially compress the heart, providing co-pulsation support. Attachment is via a novel hydrogel coating. Early versions of the wrap were tested in vivo using a single ventricle congenital heart disease model with postcardiotomy shock, which proved unstable and demonstrated high peri-operative mortality. The final wrap design was tested in 4 acute studies with piglets (5.1 ± 0.3 kg), where the combination of ASD and PA banding induced acute right ventricular dysfunction. Data collected included routine hemodynamic values, TEE, video of the exposed heart, and cardiac histology. The model proved stable for support durations ranging from 2 to 16 hours. The wrap restricted the heart in 3 of the 4 animals, as evidenced by increased diastolic LVP during support compared to the baseline failure condition. TEE and video data showed good attachment and function of the wrap, particularly during the final 16 hr study. This model of congenital heart disease shows promise for chronic (24-72 hr) studies. Ventricular filling during support may be improved by adjusting wrap dimensions to eliminate end diastolic restriction.