Publications by authors named "Prior D"

Background: We evaluated whether the use of glycoprotein IIb/IIIa receptor inhibitors, in addition to heparin and aspirin, imparts an incremental benefit in a subgroup of patients with acute coronary syndromes (ACS) who had congestive heart failure (CHF) symptoms at presentation.

Methods: We analyzed patients enrolled in the Platelet IIb/IIIa in Unstable Angina: Receptor Suppression Using Integrilin Therapy (PURSUIT) trial, a randomized, double-blind, placebo-controlled study evaluating the use of eptifibatide versus placebo for patients with ACS without persistent ST-elevation. We compared the clinical characteristics and 30-day outcomes for 861 patients who had Killip class II or III CHF symptoms with those of 8558 patients who had no CHF symptoms.

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When combined with capillary LC separations, electrospray ionization-Fourier transform ion cyclotron resonance mass spectrometry (ESI-FTICR MS) has demonstrated capabilities for advanced characterization of proteomes based upon analyses of proteolytic digests. Incorporation of external (to the ICR cell) multipole devices with FTICR for ion selection and ion accumulation has enhanced the dynamic range, sensitivity, and duty cycle of measurements. However, the highly variable ion production rate from an LC separation can result in "overfilling" of the external trap during the elution of major peaks and result in m/z discrimination and fragmentation of peptide ions.

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Background: The effects of morbid obesity, pneumoperitoneum (PP) and body position on cardiac function during laparoscopy were studied.

Methods: Transesophageal echocardiography (TEE) was performed on 10 obese patients (body mass index, BMI, 48.1+/-1.

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Unlabelled: We hypothesize that a simplified version of the Euler equation (SEE) utilizing differences in velocity over a distance and time as obtained by Color Doppler M-mode (CMM) echocardiography can approximate actual peak transmitral pressure gradients deltaP(TM).

Methods: In 14 patients undergoing open-heart surgery, deltaP(TM) was measured under various hemodynamic conditions using 2 high fidelity transducers, 5 cm apart. Transesophageal CMM images were simultaneously acquired and a customized image analysis application was used to abstract spatiotemporal velocity characteristics.

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Reconstruction of 3D structures of specimens embedded for light or electron microscopy is usually achieved by cutting serial sections through the tissues, then assembling the images from each section to reconstruct the original structure or feature. This is both time-consuming and destructive, and may lead to areas of particular interest being missed. This paper describes a method of examining specimens which have been fixed in glutaraldehyde and embedded in epoxy resin, by utilising the autofluorescence preserved or enhanced by aldehyde fixation, and by using a confocal laser scanning microscope to section optically such specimens in the block down to a depth of about 200 &mgr;m.

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Objective: Rheumatoid arthritis (RA) is associated with increased rates of cardiovascular disease. Reduced small artery elasticity (SAE) and large artery elasticity (LAE) and increased systemic vascular resistance (SVR) have been found in other high-risk groups. In the present study, we sought to determine whether arterial elasticity was reduced and SVR was increased in RA patients compared with controls matched for coronary artery disease (CAD) status, and to relate the results to vascular disease risk factors, including measures of inflammation.

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In-situ heating experiments have been conducted at temperatures of approximately 1200 K utilising a new design of scanning electron microscope, the CamScan X500. The X500 has been designed to optimise the potential for electron backscatter diffraction (EBSD) analysis with concomitant in-situ heating experimentation. Features of the new design include an inclined field emission gun (FEG) column, which affords the EBSD geometrical requirement of a high (typically 160 degrees) angle between the incoming electron beam and specimen surface, but avoids complications in heating-stage design and operation by maintaining it in a horizontal orientation.

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Background: Newer contrast agents as well as tissue harmonic imaging enhance left ventricular (LV) endocardial border delineation, and therefore, improve LV wall-motion analysis. Interpretation of dobutamine stress echocardiography is observer-dependent and requires experience. This study was performed to evaluate whether these new imaging modalities would improve endocardial visualization and enhance accuracy and efficiency of the inexperienced reader interpreting dobutamine stress echocardiography.

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Caring is an attribute of palliative nursing that is assumed to be fundamental. However, as the sophistication of palliative care increases, the liberal art of caring has become submerged under the weight of medical and pharmacological sciences. The nursing profession defends caring as the essence of its practice yet caring work in the palliative environment receives relatively little attention in research or in literature generally.

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Data-dependent external m/z selection and accumulation of ions is demonstrated in use with ESI-FTICR instrumentation, with two different methods for ion selection being explored. One method uses RF/DC quadrupole filtering and is described in use with an 11.5 tesla (T) FTICR instrument, while the second method employs RF-only resonance dipolar excitation selection and is described in use with a 3.

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Aims: Congestive heart failure (CHF) is associated with a high readmission rate after diagnosis. We assessed the ability of a comprehensive management program (CMP) for CHF to reduce readmissions with secondary endpoints of improving quality of life, exercise capacity and targeted drug doses.

Methods And Results: Patients (pts) with: New York Heart Association Class (NYHA) III or IV CHF; left ventricular ejection fraction <40%; and stable outpatient therapy were assigned to a CMP of cardiology assessment intensive education and referral to a tailored exercise program.

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Objectives: We aimed to validate a new flow convergence (FC) method that eliminated the need to locate the regurgitant orifice and that could be performed semiautomatedly.

Background: Complex and time-consuming features of previously validated color Doppler methods for determining mitral regurgitant volume (MRV) have prevented their widespread clinical use.

Methods: Thirty-nine different hemodynamic conditions in 12 sheep with surgically created flail leaflets inducing chronic mitral regurgitation were studied with two-dimensional (2D) echocardiography.

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Background: Early diastolic intraventricular pressure gradients (IVPGs) have been proposed to relate to left ventricular (LV) elastic recoil and early ventricular "suction." Animal studies have demonstrated relationships between IVPGs and systolic and diastolic indices during acute ischemia. However, data on the effects of improvements in LV function in humans and the relationship to IVPGs are lacking.

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To validate a previously proposed simplified proximal flow convergence method for calculating mitral regurgitant orifice area (ROA), a prospective study was conducted in ambulatory patients and in patients undergoing open heart surgery. Assuming a pressure difference between the left ventricle and left atrium of approximately 100 mm Hg (jet velocity [v(p)] 500 cm/s) and setting the color aliasing velocity (v(a)) to 40 cm/s, we simplified the conventional proximal convergence method formula (ROA = 2pi(r2)v(a)/v(p)) to r2/2, where r is the radius of the proximal convergence isovelocity hemisphere. For 57 ambulatory patients with a wide range of mitral regurgitant severity (1 to 4+), ROA was calculated by the conventional (x) and simplified (y) methods, demonstrating excellent accuracy (r = 0.

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Background And Aim Of The Study: The non-invasive evaluation of mitral valve area is often used in the assessment of patients with mitral stenosis. The pressure half-time method is commonly used to calculate valve area, but is inaccurate in many clinical scenarios. We sought to quantify the effects of changing cardiac output on the accuracy of mitral valve area determination.

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Shortened early transmitral deceleration times (E(DT)) have been qualitatively associated with increased filling pressure and reduced survival in patients with cardiac disease and increased left ventricular operating stiffness (K(LV)). An equation relating K(LV) quantitatively to E(DT) has previously been described in a canine model but not in humans. During several varying hemodynamic conditions, we studied 18 patients undergoing open-heart surgery.

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In national health services, where there is a tendency towards a lack of resources and a continuous increase in demand, it is necessary to implement decisions that promote efficiency. In this paper we focus on potential diversification economies as a strategy to increase efficiency levels. We evaluate the change in efficiency in Catalan hospitals between 1987 and 1992, and analyse the presence of possible diversification economies in each hospital.

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Background: Although some patients report favorable activity levels late after partial left ventriculectomy (PLV), their exercise physiology has not been well described.

Methods And Results: We performed upright bicycle hemodynamics in 10 patients (9 men) aged 56+/-12 years at 1.7 years after PLV.

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We examined the effect of tissue harmonic imaging on the echocardiographic splitability score and valve area measurement of 40 patients with rheumatic mitral stenosis. Planimetered valve areas were unaffected by the use of harmonic imaging, but valve scores were increased, particularly in patients with scores <10.

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The simplified Bernoulli equation relates fluid convective energy derived from flow velocities to a pressure gradient and is commonly used in clinical echocardiography to determine pressure differences across stenotic orifices. Its application to pulmonary venous flow has not been described in humans. Twelve patients undergoing cardiac surgery had simultaneous high-fidelity pulmonary venous and left atrial pressure measurements and pulmonary venous pulsed Doppler echocardiography performed.

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Patients with heart failure exhibit impaired endothelium-dependent vasodilation. Although brief intraarterial administration of L-arginine improves endothelium-dependent vasodilatation in these patients, long-term oral supplementation is ineffective. To resolve these conflicting findings, we examined the effect of a single, short-term oral dose of L-arginine on serial, hourly forearm vascular responses to acetylcholine, sodium nitroprusside, and norepinephrine.

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Background: Transesophageal echocardiography (TEE) is the gold standard for evaluation of the left atrium and the left atrial appendage (LAA) for the presence of thrombi. Anticoagulation is conventionally used for patients with atrial fibrillation to prevent embolization of atrial thrombi. The mechanism of benefit and effectiveness of thrombi resolution with anticoagulation is not well defined.

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A new electrodynamic (rf) ion funnel has been developed and evaluated for use in the interface regions (at approximately 1-10 Torr) of atmospheric pressure ion sources (e.g., electrospray ionization (ESI) for mass spectrometry).

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Strut fracture and disk embolization of a Björk-Shiley convexo-concave valve is uncommon, but it should always be considered as a cause of sudden cardiovascular collapse in patients with such valves. Recognition of this clinical scenario is essential, given the importance of early diagnosis and the prevalence of these valves worldwide. We present a fatal case of disk embolization of a mitral prosthesis presenting with cardiogenic shock and mesenteric ischemia.

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