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BACKGROUND: Cardiac resynchronization therapy (CRT) has been demonstrated to be an effective heart failure (HF) therapy. All pivotal trials of CRT to date have used atrial-synchronous biventricular pacing wherein there is no or minimal atrial pacing. In clinical practice, however, physicians often program CRT devices to have atrial rate support pacing, either by increasing the lower rate limit or by activating the rate sensor. OBJECTIVE: The purpose of this study is to evaluate the effect of empiric atrial support pacing in patients with HF who have received a CRT defibrillator (CRT-D) device. METHODS: PEGASUS CRT is a multicenter, 3-arm, randomized clinical trial of approximately 1200 patients receiving a CRT-D device. For the first 6 weeks after implant, devices are programmed to DDD with a lower rate limit of 40 beats/min. At 6 weeks, patients are randomized to DDD-40, DDD-70, or DDDR-40. All randomized patients are followed for 1 year, and at each visit, mortality, HF events, quality of life, New York Heart Association class, and atrial and ventricular arrhythmic episodes are evaluated. An exercise substudy will also be conducted, enrolling a minimum of 375 patients. Patients in this substudy will complete 2 cardiopulmonary exercise tests to evaluate the effect pacing mode has on exercise capacity. This randomized controlled trial will address whether empiric atrial support pacing is of clinical benefit to patients with HF who receive a CRT-D device.  相似文献   
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Persistent sciatic artery is an unusual anatomical anomaly first noted in 1832. Approximately 60 to 70 cases have been documented in the literature, but none described symptomatic persistent sciatic artery presenting in the neonate. We report a case of a newborn infant who presented after birth with an atrophic right lower extremity and ischemia. Ultrasound with Doppler and magnetic resonance angiography revealed a right persistent sciatic artery with hypoplastic external iliac artery. The common femoral artery was reconstituted above the bifurcation into the superficial femoral and profunda femoral artery via collaterals from the internal iliac and the persistent sciatic artery. The infant's blood flow to the right extremity gradually improved for the next 4 days without treatment and continues to have adequate blood flow.  相似文献   
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AimTo determine predictors of rescue treatment among infants treated for retinopathy of prematurity and to evaluate their ocular outcomes at 18–24 months of corrected age.MethodsThis is a single centre retrospective study of infants who received treatment for type 1 ROP, using laser photocoagulation or anti VEGF agents. Multivariable logistic regression was used to generate a prediction model for rescue treatment of ROP. The primary outcome was an abnormal refractive outcome by 24 months of corrected age, among infants primarily treated with laser therapy.ResultsTwo hundred and eight infants (including 416 eyes) who received single (n = 151) or rescue (multiple) treatments (n = 57) were included. Ninety three percent of the infants were primarily treated with laser photocoagulation. Lower gestational age, small for gestational age, early packed red blood cell transfusion (within 2 weeks of postnatal age), and presence of Zone 1 retinopathy predicted the need for rescue treatment in treated infants [area under the receiver operating characteristic curve: 0.81 (0.73–0.89)]. The incidence of abnormal refractive outcome, assessed in a total of 174 infants, was found to be significantly higher in the rescue treatment group (67% versus 21%, adjusted odds ratio: 7.56 (3.3–17.2), P < 0.001). Myopia, very high myopia and use of spectacles was significantly higher in the rescue treatment group (P < 0.001 for each).ConclusionsRescue treatment for ROP was associated with an increased incidence of refractive errors and requirement of spectacles by 2 years of age. Larger prospective multicentre studies are required to confirm the findings from our study.Subject terms: Paediatrics, Retinal diseases  相似文献   
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Alagille syndrome, also known as arteriohepatic dysplasia, is a multisystem autosomal dominant disorder characterized by chronic cholestasis due to a paucity of intrahepatic bile ducts, peripheral pulmonary artery stenosis with associated vertebral, ocular, and renal anomalies, and characteristic facies. We report a case of Alagille syndrome in a 3‐year‐old boy with associated pruritus, follicular keratoses, palmar pits, and keratoderma‐like changes over the dorsum of the hands. There have been single isolated case reports of phrynoderma and keratoderma. Palmar pits have not been reported in the literature.  相似文献   
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Hypertrophic pachymeningitis (HP) is a rare chronic inflammatory disease of the dura mater, described in association with various infections, systemic vasculitides such as Wegener''s granulomatosis and giant cell arteritis. However, HP in association with Takayasu arteritis (TA) has not been described. We report a young woman who presented with headache, seizures, and right third and fourth cranial neuropathy. Magnetic resonance imaging of the brain showed HP in bifrontal and right temporal region extending to cavernous sinus. She was also found to have systemic hypertension, stenosis of left subclavian, and left renal artery with narrowing of abdominal aorta, satisfying the diagnostic criteria for TA. A detailed evaluation for secondary causes of HP failed to reveal an alternative etiology. This report describes an unusual association of HP in a patient with TA, also emphasizing that seizures and cranial neuropathy may further expand the spectrum of neurological manifestations in patients with TA.  相似文献   
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