tbuckley/cabot-search huggingface dataset:
Paroxysmal supraventricular tachycardia in patients with mitral valve prolapse.
Authors: M EJosephson, L NHorowitz, J AKastor
Journal: Circulation (1978)

The mechanism of supraventricular tachycardia was evaluated in twelve patients with mitral valve prolapse utilizing standard intracardiac recording and stimulation techniques. Eight patients had normal electrocardiograms, three had a short PR interval and normal QRS (Lown-Ganong-Levine syndrome) and one had Wolff-Parkinson-White type A. Six of the eight patients with normal electrocardiograms were demonstrated to have atrioventricular bypass tracts. Five patients had A-V nodal re-entrant supraventricular tachycardia. In two patients the bypass tract could be demonstrated to conduct antegradely when the left atrium was paced via the coronary sinus, while in four the bypass tract only conducted retrogradely. In all seven patients with atrioventricular bypass tracts, the accessory pathway was left-sided. We conclude that a) supraventricular tachycardia in the mitral valve prolapse syndrome appears related to a high frequency of bypass tracts; b) electrophysiological studies are required to diagnose these byp...
Technetium-99m hexakis 2-methoxy-2-isobutyl isonitrile and thallium-201 extraction, washout, and retention at varying coronary flow rates in rabbit heart.
Authors: R CMarshall, E MLeidholdt, D YZhang, C ABarnett
Journal: Circulation (1990)

Technetium-99m hexakis 2-methoxy-2-isobutyl isonitrile (Tc-MIBI) and thallium-201 extraction, washout, and retention were investigated and compared in 20 isolated, isovolumic, retrograde blood-perfused rabbit hearts at flow rates ranging from 0.5 to 3.5 ml/g wet wt min-1 in the absence of tracer recirculation. Mean Tc-MIBI peak instantaneous extraction was lower (0.55 +/- 0.10, p less than 0.001) and more affected by flow rate (p less than 0.05) than 201Tl peak instantaneous extraction (0.83 +/- 0.06). In contrast, the rate of 201Tl washout was significantly faster (p less than 0.05) and initially more dependent on perfusion rate (p less than 0.05) than Tc-MIBI washout. Reflecting its higher peak instantaneous extraction, 201Tl retention was 55-79% higher immediately after isotope injection (p less than 0.001) than Tc-MIBI retention, and relative changes in maximal 201Tl net uptake correlated better (p less than 0.05) with relative flow changes than maximal Tc-MIBI net uptake. However, due to its faster w...
The effects of short-term venous congestion on forearm venous volume and reactive hyperemia blood flow in human subjects.
Authors: RZelis, RCapone, EMansour, J MField
Journal: Circulation (1978)

Congestive heart failure is associated with a reduction in limb venous volume at an effective venous pressure of 30 mm Hg (VV[30]). Further, an attenuated arteriolar dilation in response to a metabolic stimulus has been demonstrated. It was the purpose of this study to determine to what extent the chronic elevation in venous pressure seen in heart failure might explain these abnormalities of the limb circulation. Ten normal human volunteers were subjected to venous congestion of one arm for three hours at 70 mm Hg. A mercury-in-rubber strain gauge plethysmograph was used to measure forearm VV [30] and forearm blood flow at rest after release of five minutes of arterial occlusion (the reactive hyperemia response). Congestion reduced VV [30] 22%, resting forearm blood flow 49% and peak reactive hyperemia blood flow 25%. Thus, chronic venous congestion per se may significantly reduce limb venous volume as well as resting and reactive hyperemia blood flow.
Influence of the Number of Endoscopists Performing ERCP on the Outcomes of the Procedure
Authors: A Arrubla, I Rodríguez Mendiluce, N Hervas, J Carrascosa, V Jusue, F Estremera, L Uribarri, V Busto, M Gomez, I Fernandez Urien, E Albeniz, JJ Vila
Journal: Endoscopy (2021)

Aims To evaluate the impact of the number of endoscopists performing ERCP on the outcomes of this procedure in our hospital.
Progression of coronary atherosclerosis.
Authors: J RKramer, YMatsuda, J CMulligan, MAronow, W LProudfit
Journal: Circulation (1981)

Two hundred sixty-two patients with 50% or greater obstruction of at least one coronary artery on the initial study underwent recatheterization 2-182 months later and were evaluated for progressive arterial changes. Progression was considered present if (1) a change from less than total obstruction to total obstruction occurred in any vessel; (2) a change from 70% or less to 90% or more occurred in any vessel; (3) a change from 30% or less to 50% or more occurred in any vessel not initially obstructed by 50%; or (4) a 20% or more increase in obstruction was noted in any vessel already narrowed 50% or more. Of the 262 patients, 116 of 238 men (49%) and 12 of 24 women (50%) met the criteria for progression. Risk factors determined at the time of the initial catheterization in patients who met the criteria for progression were compared with risk factors in patients who did not. No significant difference could be found between the groups in relation to family history, blood pressure, diabetes, smoking habits,...
Covid-19: Brazil’s spiralling crisis is increasingly affecting young people
Authors: Luke Taylor
Journal: BMJ (2021)

19: Brazil's spiralling crisis is increasingly affecting young people Luke TaylorBrazil continues to break records for all the wrong reasons as it faces its deadliest episode of the pandemic yet, amid an escalating political crisis.More than 3780 covid-19 deaths were recorded on 30 March, six days after the country recorded its 300 000th life lost to the illness.At least 60 000 Brazilians died with covid-19 in March as the more transmissible variant known as P.1 spread across the country.
Platelets, immune cells and the coagulation cascade; friend or foe of the circulating tumour cell?
Authors: Mark P. Ward, Laura E. Kane, Lucy A. Norris, Bashir M. Mohamed, Tanya Kelly, Mark Bates, Andres Clarke, Nathan Brady, Cara M. Martin, Robert D. Brooks, Doug A. Brooks, Stavros Selemidis, Sean Hanniffy, Eric P. Dixon, Sharon A. O’Toole, John J. O’Leary
Journal: Molecular Cancer (2021)

Abstract Cancer cells that transit from primary tumours into the circulatory system are known as circulating tumour cells (CTCs). These cancer cells have unique phenotypic and genotypic characteristics which allow them to survive within the circulation, subsequently extravasate and metastasise. CTCs have emerged as a useful diagnostic tool using “liquid biopsies” to report on the metastatic potential of cancers. However, CTCs by their nature interact with components of the blood circulatory system on a constant basis, influencing both their physical and morphological characteristics as well as metastatic capabilities. These properties and the associated molecular profile may provide critical diagnostic and prognostic capabilities in the clinic. Platelets interact with CTCs within minutes of their dissemination and are crucial in the formation of the initial metastatic niche. Platelets and coagulation proteins also alter the fate of a CTC by influencing EMT, promoting pro-survival signalling and aiding in evading immune cell destruction. CTCs have the capacity to directly hijack immune cells and utilise them to aid in CTC metastatic seeding processes. The disruption of CTC clusters may also offer a strategy for the treatment of advance staged cancers. Therapeutic disruption of these heterotypical interactions as well as direct CTC targeting hold great promise, especially with the advent of new immunotherapies and personalised medicines. Understanding the molecular role that platelets, immune cells and the coagulation cascade play in CTC biology will allow us to identify and characterise the most clinically relevant CTCs from patients. This will subsequently advance the clinical utility of CTCs in cancer diagnosis/prognosis.
Long-term yield of pancreatic cancer surveillance in high-risk individuals
Authors: Kasper A Overbeek, Iris J M Levink, Brechtje D M Koopmann, Femme Harinck, Ingrid C A W Konings, Margreet G E M Ausems, Anja Wagner, Paul Fockens, Casper H van Eijck, Bas Groot Koerkamp, Olivier R C Busch, Marc G Besselink, Barbara A J Bastiaansen, Lydi M J W van Driel, Nicole S Erler, Frank P Vleggaar, Jan-Werner Poley, Djuna L Cahen, Jeanin E van Hooft, Marco J Bruno
Journal: Gut (2021)

We aimed to determine the long-term yield of pancreatic cancer surveillance in hereditary predisposed high-risk individuals.From 2006 to 2019, we prospectively enrolled asymptomatic individuals with an estimated 10% or greater lifetime risk of pancreatic ductal adenocarcinoma (PDAC) after obligatory evaluation by a clinical geneticist and genetic testing, and subjected them to annual surveillance with both endoscopic ultrasonography (EUS) and MRI/cholangiopancreatography (MRI/MRCP) at each visit.366 individuals (201 mutation-negative familial pancreatic cancer (FPC) kindreds and 165 PDAC susceptibility gene mutation carriers; mean age 54 years, SD 9.9) were followed for 63 months on average (SD 43.2). Ten individuals developed PDAC, of which four presented with a symptomatic interval carcinoma and six underwent resection. The cumulative PDAC incidence was 9.3% in the mutation carriers and 0% in the FPC kindreds (p<0.001). Median PDAC survival was 18 months (range 1-32). Surgery was performed in 17 individuals (4.6%), whose pathology revealed 6 PDACs (3 T1N0M0), 7 low-grade precursor lesions, 2 neuroendocrine tumours <2 cm, 1 autoimmune pancreatitis and in 1 individual no abnormality. There was no surgery-related mortality. EUS detected more solid lesions than MRI/MRCP (100% vs 22%, p<0.001), but less cystic lesions (42% vs 83%, p<0.001).The diagnostic yield of PDAC was substantial in established high-risk mutation carriers, but non-existent in the mutation-negative proven FPC kindreds. Nevertheless, timely identification of resectable lesions proved challenging despite the concurrent use of two imaging modalities, with EUS outperforming MRI/MRCP. Overall, surveillance by imaging yields suboptimal results with a clear need for more sensitive diagnostic markers, including biomarkers.
Emerging Endoscopic Retrograde Cholangiopancreatography in Severe Acute Cholangitis
Authors: C Macedo, M Sant’anna, D Gomes, L Elvas, N Almeida, M Gravito-Soares, S Mendes, D Perdigoto, E Camacho, P Narra Figueiredo
Journal: Endoscopy (2021)

Aims Acute cholangitis with organ failure has a mortality rate of around 100 % if rapid decompression of the bile duct does not occur. The aim of the present study was to evaluate the role of endoscopic retrograde cholangiopancreatography (ERCP) in emergent drainage at a tertiary referral center.
Myocardial infarction in rats. Infarct size, myocyte hypertrophy, and capillary growth.
Authors: PAnversa, CBeghi, YKikkawa, GOlivetti
Journal: Circulation Research (1986)

To determine the compensatory reserve capacity of the ventricular myocardium following infarction, the left coronary artery in rats was ligated, and the animals were killed 40 days later. Infarcts affecting an average 23% of the left ventricle were characterized by a 27% hypertrophic growth of the remaining myocardium that produced a complete replacement of the necrotic tissue. In contrast, infarcts with an average 50% loss of mass resulted in 83% expansion of the spared myocardium that was inadequate for a complete restoration of ventricular tissue. Myocyte hypertrophy was 26% and 78% in small and large infarcts, respectively. Cellular hypertrophy in both cases involved significant increases in myocyte transverse area and myocyte length. After large infarcts, there was an 18% reduction in capillary surface and a 16% increase in the diffusion distance. Corresponding values for small infarcts were -10% and 9%. These alterations combined with the deficient reconstitution of myocardial mass following large i...
Relation between tobacco use and urinary excretion of thromboxane A2 and prostacyclin metabolites in young men.
Authors: AWennmalm, GBenthin, E FGranström, LPersson, A SPetersson, SWinell
Journal: Circulation (1991)

BACKGROUNDCigarette smoking is a risk factor for cardiovascular disease. The present study addressed the effect of tobacco use on the formation of two eicosanoids, thromboxane A2 and prostacyclin, which have been implicated in both acute and chronic cardiovascular disorders.METHODS AND RESULTSIn 577 randomly sampled 18-19-year-old men, the urinary excretion of the 2,3-dinor metabolites of thromboxane A2 and prostacyclin (Tx-M and PGI-M, respectively) was analyzed and related to the subjects' self-reported use of tobacco. Sixty-five percent of the subjects used no tobacco, 7.5% were cigarette smokers, 22% used wet (oral) snuff, and the rest reported a mixed use of tobacco. The urinary excretion of Tx-M was higher (p less than 0.001) in cigarette smokers than in those not using tobacco (180 versus 128 pg/mg creatinine) and was correlated (r = 0.35, p less than 0.05) with the daily cigarette consumption. Snuff users had no increase in their urinary excretion of Tx-M, despite urinary cotinine levels comparabl...
Offer exercise, therapy, acupuncture, or antidepressants for chronic primary pain, says NICE
Authors: Zosia Kmietowicz
Journal: BMJ (2021)

Chronic primary pain should be managed with exercise programmes, cognitive behavioural therapy, acceptance and commitment therapy, and acupuncture, NICE has said in guidance on the assessment and management of chronic pain.1

The antidepressants amitriptyline, citalopram, duloxetine, fluoxetine, paroxetine, or sertraline are the only drug treatments that should be offered to patients with chronic primary pain because evidence shows these may improve quality of life, pain, sleep, and psychological distress, even in the absence of depression, says NICE.

For many commonly prescribed drugs, including paracetamol, non-steroidal anti-inflammatory drugs, benzodiazepines, or opioids there is little or no evidence that they make any …
Persistent dysfunction of regenerated endothelium after balloon angioplasty of rabbit iliac artery.
Authors: F FWeidinger, J MMcLenachan, M ICybulsky, J BGordon, H GRennke, N KHollenberg, J TFallon, PGanz, J PCooke
Journal: Circulation (1990)

This study investigated the vasodilator function of endothelium that regenerated after balloon angioplasty and the relation of this function to the extent of vascular injury and to subsequent intimal proliferation. Balloon angioplasty was performed in the left iliac artery of 47 New Zealand White rabbits. Vascular responses were examined in vitro 2 and 4 weeks after a severe injury (3.0-mm balloon) or a moderate injury (2.5-mm balloon). Both degrees of balloon injury caused complete endothelial denudation. Endothelial regrowth 2 weeks after either injury was confirmed histologically. Although the regenerated cells had irregular sizes and polygonal shapes and lacked the typical alignment in the direction of blood flow, immunocytochemical staining for factor VIII-related antigen identified these cells as endothelium. To study the vasodilator function of regenerated endothelium, rings of balloon-injured and control (contralateral) iliac arteries were suspended in organ chambers for recording of isometric...
Hormonal Testing and Pharmacologic Treatment of Erectile Dysfunction: A Clinical Practice Guideline From the American College of Physicians
Authors: Amir Qaseem
Journal: Annals of Internal Medicine (2009)

Description: The American College of Physicians developed this guideline to present the available evidence on hormonal testing in and pharmacologic management of erectile dysfunction. Current pharmacologic therapies include phosphodiesterase-5 (PDE-5) inhibitors, such as sildenafil, vardenafil, tadalafil, mirodenafil, and udenafil, and hormonal treatment. Methods: Published literature on this topic was identified by using MEDLINE (1966 to May 2007), EMBASE (1980 to week 22 of 2007), Cochrane Central Register of Controlled Trials (second quarter of 2007), PsycINFO (1985 to June 2007), AMED (1985 to June 2007), and SCOPUS (2006). The literature search was updated by searching for articles in MEDLINE and EMBASE published between May 2007 and April 2009. Searches were limited to English-language publications. This guideline grades the evidence and recommendations by using the American College of Physicians' clinical practice guidelines grading system. Recommendation 1: The American College of Physicians recommends that clinicians initiate therapy with a PDE-5 inhibitor in men who seek treatment for erectile dysfunction and who do not have a contraindication to PDE-5 inhibitor use (Grade: strong recommendation; high-quality evidence). Recommendation 2: The American College of Physicians recommends that clinicians base the choice of a specific PDE-5 inhibitor on the individual preferences of men with erectile dysfunction, including ease of use, cost of medication, and adverse effects profile (Grade: weak recommendation; low-quality evidence). Recommendation 3: The American College of Physicians does not recommend for or against routine use of hormonal blood tests or hormonal treatment in the management of patients with erectile dysfunction (Grade: insufficient evidence to determine net benefits and harms).
Left ventricular passive diastolic properties in chronic mitral regurgitation.
Authors: W JCorin, TMurakami, E SMonrad, O MHess, H PKrayenbuehl
Journal: Circulation (1991)

BACKGROUNDIn chronic mitral regurgitation, the myocardium responds to the increased filling volume by geometric alteration and eccentric hypertrophy. This study was designed to evaluate the effects of a pure volume overload on left ventricular diastolic chamber and myocardial properties and to assess the relation of passive diastolic function to systolic ejection performance.METHODS AND RESULTSBy use of simultaneous cineangiography and left ventricular micromanometry, left ventricular passive diastolic stiffness was evaluated in nine normal controls (group 1), 14 patients with chronic mitral regurgitation and a normal ejection fraction (greater than or equal to 57%, group 2), and 13 patients with mitral regurgitation and a reduced ejection fraction (less than 57%, group 3). Passive diastolic function was evaluated by using a three-constant elastic model. Left ventricular chamber properties were represented by the relation of pressure to volume; myocardial properties were evaluated by relating myocardial m...
The antiarrhythmic efficacy of amiodarone and desethylamiodarone, alone and in combination, in dogs with acute myocardial infarction.
Authors: SNattel, MDavies, MQuantz
Journal: Circulation (1988)

Antiarrhythmic activity of amiodarone's desethyl metabolite, which accumulates during oral amiodarone therapy, has been postulated to explain the delayed onset of antiarrhythmic effects during long-term amiodarone therapy. To determine their relative antiarrhythmic efficacy, amiodarone and its desethyl metabolite, desethylamiodarone, were administered to mongrel dogs with ventricular tachycardia 24 hr after ligation of the left anterior descending coronary artery. Cumulative doses of amiodarone, desethylamiodarone, a combination of amiodarone and desethylamiodarone, or the vehicle for drug administration were given at 1 hr intervals. Both amiodarone and desethylamiodarone suppressed ventricular arrhythmias in a dose-dependent fashion. The metabolite, however, was more potent with a 50% effective concentration for suppression of premature ventricular complexes of 1.4 mg/liter compared with 4.6 mg/liter for the parent compound. Plasma and myocardial drug concentrations were similar to those measured during ...
Observations on the optimum time for operative intervention for aortic regurgitation. I. Evaluation of the results of aortic valve replacement in symptomatic patients.
Authors: W LHenry, R OBonow, J SBorer, J HWare, K MKent, D RRedwood, C LMcIntosh, A GMorrow, S EEpstein
Journal: Circulation (1980)

Fifty consecutive patients undergoing aortic valve replacement for isolated aortic regurgitation were studied prospectively by echocardiography, electrocardiography and cardiac catheterization. Good quality echocardiograms were obtained in 49 of the 50 patients. Left ventricular (LV) dilatation was present in all 49 patients. LV systolic function, as assessed by echocardiographic percent fractional shortening, was normal in many patients but was moderately to severely reduced (less than 25%) in 14 patients (29%). Echocardiographic studies 6 months postoperatively revealed significant reductions in LV end-diastolic dimension (73.8 mm vs 58.7 mm; p less than 0.01), and serial echocardiographic studies early and late after operation revealed that the decrease in LV size had occurred by the time of the early study (8-22 days postoperatively), with little additional change thereafter. Operative deaths occurred in three of the 49 patients (6%). Eight of the 49 patients (16%) died of congestive heart failure (CH...
Survival of the ischemic brain: a progress report.
Authors: PScheinberg
Journal: Circulation (1979)

The number of patients with cerebral infarctions increases as the population ages, despite campaigns against hypertension, the greatest risk factor. Cerebral ischemia initiates events that are presumed to defer the stage of irreversible injury. These events cause an increase of perfusion around the central ischemic zone and trigger the Bohr effect, both of which preserve tissue viability. Almost simultaneously, mitochondrial function fails, resulting in insufficient energy for the enzyme systems to control Na and K ion equilibrium. At the same time, protein synthesis slows and cellular respiratory enzymes decrease their activity, initiating an irreversible state of tissue change. Tissue fatty acids increase as a result of dissolution of cell membrane lipoprotein structure. Barbiturates reduce the extent of experimental infarction. Resperine and aminophylline are also effective, but there are no corroborative clinical trials. That ischemic brain damage may be the result of toxic substances in the ischemic ...
Trial Emulation and Real-World Evidence
Authors: Rolf H. H. Groenwold
Journal: JAMA Network Open (2021)

Devon J. Boyne, PhD; Winson Y. Cheung, MD, MPH; Robert J. Hilsden, MD, PhD; Tolulope T. Sajobi, PhD; Atul Batra, MD; Christine M. Friedenreich, PhD; Darren R. Brenner, PhD
Diagnosis of noninfective cardiac mass lesions by two-dimensional echocardiography. Comparison of the transthoracic and transesophageal approaches.
Authors: AMügge, W GDaniel, AHaverich, P RLichtlen
Journal: Circulation (1991)

This study was conducted in 46 patients with cardiac thrombi, 15 patients with atrial myxomas, and 32 patients with other cardiac or paracardiac tumors. Diagnoses were subsequently proven by surgery, autopsy, computed tomography, magnetic resonance imaging, or angiography in all patients. All patients underwent precordial and transesophageal two-dimensional echocardiography to assess the various mass detection rates. Atrial myxomas and predominantly left-sided cardiac tumors were identified by both echocardiographic techniques with comparable detection rates. Left ventricular apical thrombi were detected more frequently by precordial echocardiography. In contrast, transesophageal echocardiography was superior in visualizing left atrial appendage thrombi, small and flat thrombi in the left atrial cavity, thrombi and tumors in the superior vena cava, and masses attached to the right heart and the descending thoracic aorta. These data indicate that transesophageal echocardiography leads to a clinically relev...