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PurposeThe aim of this study was to investigate the use of the electrocardiogram-derived ventricular gradient, projected on the x-axis (VGx), for detection of pulmonary hypertension (PH) and for prediction of all-cause mortality in PH patients.MethodsIn patients referred for PH screening (n = 216), the VGx was calculated semiautomatically from the electrocardiogram and was defined as abnormal when less than 24 mV·ms. The VGx of PH patients was compared with the VGx of patients without PH. The association between a reduced VGx and mortality was investigated in PH patients.ResultsPatients with PH (n = 117) had a significantly reduced VGx: 14 ± 27 vs 45 ± 23 mV·ms, P < .001. Furthermore, a severely reduced VGx (<0 mV·ms) was associated with increased mortality in PH patients: hazard ratio, 1.025 (95% confidence interval, 1.006-1.045; P = .012) per mV·ms VGx decrease.ConclusionReduced VGx is associated with the presence of PH and, more importantly, within PH patients, a severely reduced VGx predicts mortality.  相似文献   
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Cell-based therapy has emerged as a treatment modality for myocardial repair. Especially cardiac resident stem cells are considered a potential cell source since they are able to differentiate into cardiomyocytes and have improved heart function after injury in a preclinical model for myocardial infarction. To avoid or repair myocardial damage it is important not only to replace the lost cardiomyocytes, but also to remodel and replace the scar tissue by "healthy" extracellular matrix (ECM). Interestingly, the role of cardiac stem cells in this facet of cardiac repair is largely unknown. Therefore, we investigated the expression and production of ECM proteins, matrix metalloproteinases (MMPs) and their inhibitors (TIMPs) in human cardiomyocyte progenitor cells (CMPCs) undergoing differentiation towards the cardiomyogenic lineage. Our data suggest that CMPCs have the capacity to synthesize and modulate their own matrix environment, especially during differentiation towards the cardiomyogenic lineage. While undifferentiated CMPCs expressed collagen I, III, IV and fibronectin, but no elastin, during the process of differentiation the expression of collagen I, III, IV and fibronectin increased and interestingly also elastin expression was induced. Furthermore, undifferentiated CMPCs express MMP-1 -2 and -9 and upon differentiation the expression of MMP-1 decreased, while the expression of MMP-2 and MMP-9, although the latter only in the early stage of differentiation, increased. Additionally, the expression of TIMP-1, -2 and -4 was induced during differentiation. This study provides new insights into the matrix production and remodeling capacity of human CMPCs, with potential beneficial effects for the treatment of cardiac injury.  相似文献   
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In the past 20 years, radionuclide scintigraphy has proven to be a sensitive clinical tool in the assessment of myocardial perfusion abnormalities. Magnetic resonance imaging may also be used to study myocardial perfusion, but its potential value still has to emerge in the clinical setting. This review addresses the potential and achievements of both methods in clinical cardiology.  相似文献   
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Beneficial effects of recombinant human GH on cardiac function have been reported in humans with GH deficiency and in patients with idiopathic dilated cardiomyopathy. No randomized controlled trial has been performed on the effects of recombinant human GH on cardiac function in patients with ischemic cardiac failure. We therefore randomly assigned 22 patients with ischemic cardiac failure (left ventricular ejection fraction, <40%; 19 men and 3 women; mean age, 64 yr) to receive 6 months of unblinded therapy with recombinant human GH (2.0 IU/d) or no treatment. Primary end points were left ventricular ejection fraction and left ventricular mass. Left ventricular end-diastolic volume, left ventricular end-systolic volume, and myocardial perfusion, both at rest and during exercise, were assessed as well. Cardiac imaging techniques were electrocardiographically gated single photon emission computer tomography and magnetic resonance imaging. In addition, biochemical and biometric measurements were performed. Nineteen patients completed the study (10 controls and 9 GH-treated subjects). IGF-I and IGF-binding protein-3 increased significantly after recombinant human GH treatment (+24% and +58%, respectively) compared with control values (-14% and +5%; P < 0.05). Left ventricular ejection fraction, left ventricular end-diastolic volume, left ventricular end-systolic volume, left ventricular mass, and myocardial perfusion were not influenced by recombinant human GH therapy. We conclude that 6 months of recombinant human GH treatment in patients with ischemic cardiac failure had no beneficial effect on left ventricular function and mass.  相似文献   
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Background

Fecal incontinence is a common, socially debilitating disorder. Initial management involves dietary manipulation with bulking agents or antidiarrheal medications and pelvic floor biofeedback. For patients failing these modalities, traditional surgical approaches are morbid and of variable efficacy. Sacral nerve neuromodulation (Interstim, sacral nerve stimulation) was approved in May 2011 for management of medically refractory fecal incontinence. This report summarizes our experience with this treatment modality.

Methods

A prospectively maintained database from a colorectal specialty practice was reviewed from December 2011 to June 2013. Patient demographics, incontinence etiology, and medical treatment regimens were reviewed. Outcomes for Interstim placement and surgical morbidity were reviewed.

Results

A total of 330 patients were evaluated in the clinic for fecal incontinence during the study period. A total of 33 patients (10%) were offered Interstim therapy. The mean age was 63 (39 to 91) years, and 91% (30 of 33) were female. The etiology of the incontinence was obstetric (81%), rectal prolapse (11%), neurogenic (5%), and iatrogenic (3%). The entire group failed either supplemental fiber or antidiarrheal medications and 73% (24 of 33) failed pelvic floor biofeedback. The mean number of bowel accidents/2-week bowel diary before implant was 19 (9 to 52). After phase I implant, 88% (29 of 33) experienced a successful test phase and proceeded to phase II permanent implant. The mean number of bowel accidents/2-week diary postimplant was 3 (0 to 12). A trend toward less severe episodes of incontinence postimplant was observed. There were no complications associated with either the phase I or phase II implant. There were no phase II failures although 1 patient underwent device explant 9 months after phase II implant for chronic pain.

Conclusions

Sacral nerve neuromodulation (Interstim, sacral nerve stimulation) is an effective and efficacious tool for management of medically refractory fecal incontinence that offers a less morbid surgical approach to this problem. Interstim should be considered the first-line surgical approach for medically refractory fecal incontinence.  相似文献   
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