16 research outputs found
Left ventricular remodeling and hypertrophy in patients with aortic stenosis:insights from cardiovascular magnetic resonance
<p>Abstract</p> <p>Background</p> <p>Cardiovascular magnetic resonance (CMR) is the gold standard non-invasive method for determining left ventricular (LV) mass and volume but has not been used previously to characterise the LV remodeling response in aortic stenosis. We sought to investigate the degree and patterns of hypertrophy in aortic stenosis using CMR.</p> <p>Methods</p> <p>Patients with moderate or severe aortic stenosis, normal coronary arteries and no other significant valve lesions or cardiomyopathy were scanned by CMR with valve severity assessed by planimetry and velocity mapping. The extent and patterns of hypertrophy were investigated using measurements of the LV mass index, indexed LV volumes and the LV mass/volume ratio. Asymmetric forms of remodeling and hypertrophy were defined by a regional wall thickening <b>≥</b>13 mm and >1.5-fold the thickness of the opposing myocardial segment.</p> <p>Results</p> <p>Ninety-one patients (61±21 years; 57 male) with aortic stenosis (aortic valve area 0.93±0.32cm2) were recruited. The severity of aortic stenosis was unrelated to the degree (r<sup>2</sup>=0.012, P=0.43) and pattern (P=0.22) of hypertrophy. By univariate analysis, only male sex demonstrated an association with LV mass index (P=0.02). Six patterns of LV adaption were observed: normal ventricular geometry (n=11), concentric remodeling (n=11), asymmetric remodeling (n=11), concentric hypertrophy (n=34), asymmetric hypertrophy (n=14) and LV decompensation (n=10). Asymmetric patterns displayed considerable overlap in appearances (wall thickness 17±2mm) with hypertrophic cardiomyopathy.</p> <p>Conclusions</p> <p>We have demonstrated that in patients with moderate and severe aortic stenosis, the pattern of LV adaption and degree of hypertrophy do not closely correlate with the severity of valve narrowing and that asymmetric patterns of wall thickening are common.</p> <p>Trial registration</p> <p>ClinicalTrials.gov Reference Number: NCT00930735</p
Placebo-controlled comparison of candoxatril, an orally active neutral endopeptidase inhibitor, and captopril in patients with chronic heart failure
Aims:
To compare the effects on exercise capacity of the neutral endopeptidase inhibitor candoxatril, and the angiotensin converting enzyme inhibitor captopril, in patients with mild to moderate heart failure.<p></p>
Methods:
In this multi-centre double-blind placebo controlled study, 60 patients with NYHA Class I–III heart failure were randomised to candoxatril 200 mg b.d. (n = 22), captopril 25–50 mg b.d. (n = 23) or placebo (n = 15), Treadmill exercise tests were carried out weekly during a 5-week single-blind placebo run-in phase until a stable baseline was achieved, and repeated at 4 weekly intervals during the 12-week double-blind treatment phase.<p></p>
Results:
Nine patients withdrew from the study — four candoxatril and five captopril. The placebo-adjusted increase in exercise duration after 12 weeks was 56 s (95% CI, −26 to + 137 s; P = 0.12) with candoxatril and 37 s (− 40 to + 117 s; P = 0.29) with captopril.<p></p>
Conclusions:
Both candoxatril and captopril were well tolerated and treadmill exercise duration appeared to increase during 12 weeks of therapy but this did not achieve statistical significance. This study tentatively suggests that in patients with heart failure, neutral endopeptidase inhibition may provide similar symptomatic benefits to angiotensin converting enzyme inhibition.<p></p>
A real-time sound rendering algorithm for complex scenes
Available from TIB Hannover: RR 4367(2003,5) / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische InformationsbibliothekSIGLEDEGerman
Percutaneous device closure of paravalvular leak
Background: Paravalvular leak (PVL) occurs in 5% to 17% of patients following surgical valve replacement. Percutaneous device closure represents an alternative to repeat surgery. Methods: All UK and Ireland centers undertaking percutaneous PVL closure submitted data to the UK PVL Registry. Data were analyzed for association with death and major adverse cardiovascular events (MACE) at follow-up. Results: Three hundred eight PVL closure procedures were attempted in 259 patients in 20 centers (2004-2015). Patient age was 67±13 years; 28% were female. The main indications for closure were heart failure (80%) and hemolysis (16%). Devices were successfully implanted in 91% of patients, via radial (7%), femoral arterial (52%), femoral venous (33%), and apical (7%) approaches. Nineteen percent of patients required repeat procedures. The target valve was mitral (44%), aortic (48%), both (2%), pulmonic (0.4%), or transcatheter aortic valve replacement (5%). Preprocedural leak was severe (61%), moderate (34%), or mild (5.7%) and was multiple in 37%. PVL improved postprocedure (