Acute type 5 phosphodiesterase inhibition with sildenafil 25 and 50 mg increases endothelium-dependent, flow-mediated vasodilation in patients with chronic heart failure when compared with placebo.
Although definitive source identification remains elusive, we believe that the majority of bleeding arises in the small bowel, possibly due to angiodysplasias, similar to the pathophysiology encountered in patients with aortic stenosis and GI bleeding. As we move toward wider use of the HMII and other axial continuous-flow devices in both bridge-to-transplant patients and for destination therapy, more studies will be necessary to understand the mechanisms of this obscure GI bleeding and develop treatment strategies to minimize its development.
Background: Left ventricular assist device (LVAD) unloading and hemodynamic support in patients with advanced chronic heart failure can result in significant improvement in cardiac function allowing LVAD removal, however the rate of this is generally considered to be low. This prospective multicenter non-randomized study (RESTAGE-HF) investigated whether a protocol of optimized LVAD mechanical unloading, combined with standardized specific pharmacological therapy to induce reverse remodeling and regular testing of underlying myocardial function, could produce a higher incidence of LVAD explantation. Methods: Forty patients with chronic advanced heart failure from non-ischemic cardiomyopathy receiving the Heartmate II LVAD were enrolled from 6 centers. LVAD speed was optimized with an aggressive pharmacological regimen and regular echocardiograms were performed at reduced LVAD speed (6000rpm, no net flow) to test underlying myocardial function. The primary endpoint was the proportion of patients with sufficient improvement of myocardial function to reach criteria for explantation within 18 months with sustained remission from HF (freedom from transplant/VAD/death) at 12 months. Results: Prior to LVAD age was 35.1±10.8 years, 67.5% were male, heart failure mean duration was 20.8±20.6 months, 95% required inotropic and 20% temporary mechanical support, left ventricular ejection fraction (LVEF) was 14.5±5.3%, end-diastolic diameter (LVEDD) 7.33±0.89cm, end-systolic diameter (LVESD) 6.74±0.88cm, PA saturations were 46.7±9.2% and pulmonary capillary wedge pressure (PCWP) was 26.2±7.6mmHg. Four enrolled patients did not undergo the protocol due to medical complications unrelated to the study procedures. Overall 40% of all enrolled (16/40) patients achieved the primary endpoint, p<0.0001, with 50% (18/36) of patients receiving the protocol being explanted within 18 months (pre-explant LVEF 57±8%; LVEDD 4.81±0.58cm; LVESD 3.53±0.51cm; PCWP 8.1±3.1mmHg; PA sats 63.6±6.8% at 6000rpm). Overall 19 patients were explanted (19/36, 52.3% of those receiving the protocol). The fifteen ongoing explanted patients are now 2.26±0.97years post explant. Post-explantation survival free from LVAD or transplantation was 90% at 1-year and 77% at 2 and 3 years. Conclusions: In this multicenter prospective study, this strategy of LVAD support combined with a standardized pharmacologic and cardiac function monitoring protocol resulted in a high rate of LVAD explantation and was feasible and reproducible with explants occurred in all six participating sites.
The degree of bone loss and the rates of fracture did not differ significantly between the intervention groups. Calcitriol was associated with a higher risk of hypercalciuria. Alendronate-treated patients sustained less bone loss at the spine than those in the reference group, and both intervention groups sustained less bone loss at the hip than the reference group. The requirement for monitoring the serum and urinary calcium levels in calcitriol-treated patients makes alendronate more attractive for the prevention of bone loss early after cardiac transplantation.
Background-Myocardial recovery after left ventricular assist device (LVAD) support has been reported. The LVAD Working Group Recovery Study was a prospective multicenter trial to assess the incidence of myocardial recovery in patients bridged to cardiac transplantation. Methods and Results-After LVAD implantation, patients were evaluated with the use of rest echocardiograms with partial LVAD support and cardiopulmonary exercise testing. Dobutamine echocardiography with hemodynamic measurements was performed in those patients with left ventricular ejection fraction Ͼ40% during resting studies.Histological analysis was performed on myocardial samples taken at LVAD implantation and explantation. Sixty-seven LVAD patients with heart failure participated in the study. 001).Tissue analysis revealed significant reductions in myocyte size, collagen content, and cardiac tumor necrosis factor-␣. Six subjects (9%) underwent LVAD explantation for recovery. Conclusions-Cardiac function improves significantly after device implantation. Although cellular recovery and improvement in ventricular function are observed, the degree of clinical recovery is insufficient for device explantation in most patients with chronic heart failure.
AimsMyostatin inhibits myoblast differentiation/proliferation and may play a role in heart failure (HF) and reverse remodelling after left ventricular assist device (LVAD) support. This study sought to characterize myostatin expression and activation in advanced HF before and after LVAD support. Methods and resultsLeft ventricular tissue pairs were collected at LVAD implantation (core) and at cardiac transplantation/LVAD explantation in patients with advanced ischaemic (ICM-ischaemic cardiomyopathy) and non-ischaemic (DCM-dilated cardiomyopathy) HF. Normal cardiac tissue (control) was obtained from hearts not placed for transplantation. Serum was collected independently from patients with stable DCM HF and from healthy controls. Full-length and cleaved propeptide myostatin levels were quantified by western blot analysis. Dilated cardiomyopathy propeptide levels at core were significantly higher than control and significantly increased after LVAD support. Ischaemic cardiomyopathy propeptide levels were higher than control, but did not change after LVAD support. No changes in full-length levels were seen. Serum myostatin levels were significantly higher in DCM HF patients than in healthy controls. ConclusionThis is the first clinical evidence that myostatin activation is increased in HF. Myostatin may affect cardiac hypertrophy and may mediate regression of cellular hypertrophy after mechanical unloading.--
Autosomal recessive limb girdle muscular dystrophies 2C-2F represent a family of diseases caused by primary mutations in the sarcoglycan genes. We show that sarcospan, a novel tetraspan-like protein, is also lost in patients with either a complete or partial loss of the sarcoglycans. In particular, sarcospan was absent in a gamma-sarcoglycanopathy patient with normal levels of alpha-, beta- and delta-sarcoglycan. Thus, it is likely that assembly of the complete, tetrameric sarcoglycan complex is a prerequisite for membrane targeting and localization of sarcospan. Based on our findings that sarcospan is integrally associated with the sarcoglycans, we screened >50 autosomal recessive muscular dystrophy cases for mutations in sarcospan. Although we identified three intragenic polymorphisms, we did not find any cases of muscular dystrophy associated with primary mutations in the sarcospan gene. Finally, we have identified an important case of limb girdle muscular dystrophy and cardiomyopathy with normal expression of sarcospan. This patient has a primary mutation in the gamma-sarcoglycan gene, which causes premature truncation of gamma-sarcoglycan without affecting assembly of the mutant gamma-sarcoglycan into a complex with alpha-, beta- and delta-sarcoglycan and sarcospan. This is the first demonstration that membrane expression of a mutant sarcoglycan-sarcospan complex is insufficient in preventing muscular dystrophy and cardiomyopathy and that the C-terminus of gamma-sarcoglycan is critical for the functioning of the entire sarcoglycan-sarcospan complex. These findings are important as they contribute to a greater understanding of the structural determinants required for proper sarcoglycan-sarcospan expression and function.
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