tbuckley/cabot-search huggingface dataset:
Recurrent ischemia more than 1 year after successful percutaneous transluminal coronary angioplasty. An analysis of the extent and anatomic pattern of coronary disease.
Authors: R KBottner, C EGreen, C JEwels, ERecientes, G APatrissi, K MKent
Journal: Circulation (1989)

Of 1,181 consecutive patients who underwent successful percutaneous transluminal coronary angioplasty (PTCA) as an initial revascularization procedure and who had at least 1 year of asymptomatic follow-up, 66 (6%) underwent repeat angiography because of recurrent symptoms or evidence of exercise-induced ischemia. Patients who had revascularization procedures within 1 year of PTCA were not included in the analysis. Mean time to recurrent ischemia was 30.8 +/- 17.4 months (range 12-89 months). At follow-up, 47 patients had angina, 13 had atypical chest pain, two had acute myocardial infarction, and four had positive exercise tests without symptoms. No patient showed spontaneous regression in the extent of coronary artery disease (CAD). As compared with the extent of CAD immediately after PTCA, the extent of CAD at follow-up did not change in 26 patients (39%); it increased by one vessel in 30 (45%), by two vessels in seven (11%), and by three vessels in three (5%). The pattern of CAD seen at follow-up compa...
Doppler echocardiographic assessment of the St. Jude Medical prosthetic valve in the aortic position using the continuity equation.
Authors: E RChafizadeh, W AZoghbi
Journal: Circulation (1991)

To test whether the continuity equation can be applied to the noninvasive assessment of prosthetic aortic valve function, Doppler echocardiography was performed in 67 patients (mean age, 58 +/- 14 years) within 10 +/- 6 days after valve replacement with St. Jude Medical valves. All patients were clinically stable and without evidence of valve dysfunction. Valve size ranged from 19 to 31 mm, and ejection fraction ranged from 30% to 75%. With the parasternal long-axis view, the left ventricular outflow diameter measured just proximal to the prosthetic valve correlated well with valve size (r = 0.92). Doppler-derived maximal gradients ranged from 9 to 71 mm Hg. Effective prosthetic aortic valve area by the continuity equation ranged between 0.73 cm2 for a 19-mm valve and 4.23 cm2 for a 31-mm valve. With analysis of variance, effective orifice area differentiated various valve sizes (p less than 10(-14)) better than did gradients alone (p = 0.003) and correlated better with actual valve orifice area (r = 0.83...
Myocardial infarction in young patients: an analysis by age subsets.
Authors: B DHoit, E AGilpin, HHenning, A AMaisel, HDittrich, JCarlisle, JRoss
Journal: Circulation (1986)

We examined, in age subsets, 2643 patients with acute myocardial infarction. Clinical features and 1 year morbidity and mortality were compared in 203 young patients (less than 45 years), 1671 patients 46 to 70 years old, and 769 elderly patients (greater than 70 years). Ninety-two percent of young patients were men, and a family history of premature coronary artery disease was more common in young patients (41% compared with 28% of middle-aged and 12% of elderly patients). More young patients were currently smoking cigarettes (82% compared with 56% of middle-aged and 24% of elderly patients), and only 8% of young patients had never smoked. Previous myocardial infarction and history of angina pectoris or congestive heart failure were less common (p less than .001) in the young patients than in middle-aged and elderly patients. In-hospital mortality was only 2.5% for young patients, compared with 9.0% in middle-aged and 21.4% in elderly patients (both p less than .001). Postdischarge 1 year mortality was a...
The effect of indomethacin blockade of prostaglandin synthesis on blood pressure of normal rabbits and rabbits with renovascular hypertension.
Authors: J CRomero, C GStrong
Journal: Circulation Research (1977)

Indomethacin inhibits the synthesis of prostaglandin and the release of renin. These effects were studied in normal rabbits and rabbits with two-kidney Goldblatt hypertension (2KGH) and one-kidney Goldblatt hypertension (1KGH) by giving daily intravenous injections of indomethacin (3mg/kg after two initial doses of 9 mg/kg), and in appropriate control rabbits given diluent phosphate buffer without indomethacin. In normal rabbits, indomethacin significantly decreased immunoreactive plasma prostaglandin E-like substance (IPGE) and plasma renin activity (PRA). Indomethacin did not change plasma creatinine (PCr) or mean blood pressure but it decreased renal blood flow (RBF) and glomerular filtration rate (GFR). In 2KGH rabbits, responses depended on the level of renal function and, to a lesser extent, on the level of PRA. In six of10 2KGH rabbits in which hypertension developed without significant changes in PRA, IPGE, PCr, RBF, and GFR, indomethacin produced changes similar to those seen in normals. In the o...
Beneficial actions of N-dimethyl propranolol on myocardial oxygen balance and transmural perfusion gradients distal to a severe coronary artery stenosis in the canine heart.
Authors: G JGross, D CWarltier, H FHardman
Journal: Circulation (1978)

The purpose of the present study was to compare the effects of N-dimethyl propranolol (DMP), the quaternary derivative of propranolol, and propranolol on the transmural distribution (endo/epi) of coronary blood flow in normal and ischemic regions of the myocardium. The distribution of blood flow between subendocardium and subepicardium of a nonischemic region and one distal to a severe left circumflex coronary artery stenosis was determined by use of tracer microspheres (15 microgram) in intact dog hearts. DMP (1,5 and 10 mg/kg I.V.) produced a small dose-related increase in endo/epi of the nonischemic region (1.15 +/- 0.04--1.24 +/- 0.05), whereas a larger increase was observed in the ischemic region (0.61 +/- 0.08--1.09 +/- 0.10). DMP also produced a significant increase in ischemic subendocardial blood flow (0.59 +/- 0.12--0.76 +/- 0.11 ml/min/g). Similarly, propranolol (0.5 and 1.0 mg/kg I.V.) produced a small increase in endo/epi of the nonischemic region (1.18 +/- 0.08--1.30 +/- 0.07) and a larger i...
The effects of beta-adrenergic stimulation on the frequency-dependent electrophysiologic actions of amiodarone and sematilide in humans.
Authors: P TSager, CFollmer, PUppal, CPruitt, RGodfrey
Journal: Circulation (1994)

BACKGROUNDThe autonomic nervous system appears to play an important role in the development of clinical ventricular arrhythmias, and beta-adrenergic sympathetic stimulation may be important in modulating the electrophysiologic effects of class III antiarrhythmic agents. This study prospectively determined the effects of isoproterenol on the frequency-dependent actions of sematilide (a pure class III agent that selectively blocks the delayed rectifier potassium current) and amiodarone (a class III agent with a complex pharmacologic profile) on ventricular repolarization, refractoriness, and conduction.METHODS AND RESULTSThe frequency-dependent electrophysiologic effects of sematilide (n = 11) and amiodarone (n = 22) were determined at (1) drug-free baseline, (2) during steady-state (> 48 hours) dosing with sematilide (455 +/- 5 mg/d [mean +/- SEM]) or after 10.5 days of amiodarone loading (1618 +/- 32 mg/d), and (3) during isoproterenol administration (35 ng/kg per minute) to patients receiving sematilide ...
Value of two-dimensional echocardiography in endomyocardial disease with and without eosinophilia. A clinical and pathologic study.
Authors: HAcquatella, N BSchiller, J JPuigbó, J RGómez-Mancebo, CSuarez, GAcquatella
Journal: Circulation (1983)

Ten patients (six women and four men) with endomyocardial disease, four with and six without hypereosinophilia, were studied by two-dimensional echocardiography (2-D echo). Eight had biventricular congestive heart failure and two had atypical chest pain with ischemic electrocardiographic changes. The patients were 15-50 years old (mean 40 years) and duration of illness was 2-9 years (mean 4.4 years). Nine had cardiac catheterization and three pathologic examination. Characteristic 2-D echo findings included apical obliteration of one or both ventricles by echogenic material suggestive of fibrosis or thrombosis; bright, specular echoes at the cavity surface of the apical obliteration suggesting patchy calcification; preserved left apical systolic inward motion, which differed significantly from the dyskinetic motion of thrombotic apical obliteration of ischemic or Chagasic origin (p less than 0.001); involvement of the papillary muscles and posterior atrioventricular valve; preserved ventricular contractil...
Echocardiographic study of the morphology and growth of the aortic arch in the human fetus. Observations related to the prenatal diagnosis of coarctation.
Authors: L KHornberger, R GWeintraub, EPesonen, AMurillo-Olivas, I ASimpson, CSahn, SHagen-Ansert, D JSahn
Journal: Circulation (1992)

BACKGROUNDIn a study of normal and abnormal growth of the aorta before birth, high-resolution echocardiographic imaging of the aortic arch in 92 normal fetuses aged 16-38 weeks was used to establish normal values for aortic arch dimensions at varying gestational ages.METHODS AND RESULTSFrom long-axis views of the aortic arch, the internal diameter of the aortic root, ascending aorta, transverse aortic arch, aortic isthmus, proximal descending thoracic aorta, and left common carotid artery were measured. Correlation coefficients for the diameter of each aortic arch segment when related to gestational age varied from r = 0.87 to r = 0.94 (p less than 0.001 for each), and growth curves were derived from the third and 97th percentiles around each linear regression analysis. In most of the fetuses, there was progressive tapering of the aortic arch, with the smallest diameter being at the isthmus. The ratio of the transverse aorta, isthmus, descending aorta, and aortic root to the ascending aorta remained relat...
Systolic thickening and thinning of the septum and posterior wall in patients with coronary artery disease, congestive cardiomyopathy, and atrial septal defect.
Authors: B CCorya, SRasmussen, HFeigenbaum, S BKnoebel, M JBlack
Journal: Circulation (1977)

Echocardiographic septal and posterior wall thicknesses and the percent change with systole were measured in 146 patients with the following diagnoses: acute myocardial infarction (40), chronic coronary artery disease (49), congestive cardiomyopathy (8), atrial septal defect (20), and no cardiac disease (29). Mean diastolic thicknesses for the groups of patients with coronary artery disease and congestive cardiomyopathy were not significantly different from normal although there were abnormal values for individual patients within each group. Mean diastolic thickness of the septum was greater than normal for the group with atrial septal defect (P less than 0.02). Wall thinning with systole was associated with acute infarction or ischemia (P less than 0.0001); decreased thickening (less than normal) commonly occurred in patients with acute myocardial infarction, chronic coronary artery disease, and congestive cardiomyopathy. Patients with atrial septal defect had normal thickening with abnormal motion. Resu...
The angiographic effect of ergonovine and nifedipine in coronary artery spasm.
Authors: SRich, L EFord, JAl-Sadir
Journal: Circulation (1980)

In a patient with variant angina, we have shown that the calcium-channel blocker nifedipine inhibits both spontaneous and ergonivine-induced coronary artery spasm. It had no effect, however, on the dose-related diffuse vasoconstriction caused by ergonovine, suggesting two distinct responses of coronary arteries to ergonovine provocation. Nifedipine did not cause epicardial coronary artery dilatation, as did nitroglycerin, supporting the rationale of using both therapies together to treat coronary artery spasm.
A comparison of adenosine-induced cardioprotection and ischemic preconditioning in dogs. Efficacy, time course, and role of KATP channels.
Authors: ZYao, G JGross
Journal: Circulation (1994)

BACKGROUNDAdenosine has been proposed to be an important mediator of ischemic preconditioning. Intracoronary administration of adenosine has recently been shown to mimic the effects of preconditioning in isolated rabbit hearts. However, it is not known whether this agent can duplicate the effects of preconditioning in vivo or in other species. Thus, the first objective of the present study was to determine whether adenosine can limit myocardial necrosis to the same extent as preconditioning in anesthetized dogs. A second objective was to determine whether the duration of the adenosine-induced cardioprotection persisted as long as that of ischemic preconditioning. Finally, a third aim was to determine whether adenosine mediates its cardioprotection via the KATP channel, which has been shown to be an important mediator of preconditioning in several animal species, including dogs.METHODS AND RESULTSBarbital-anesthetized open-chest dogs were subjected to 60 minutes of left anterior descending coronary artery ...
Utility of Fetal Cardiovascular Magnetic Resonance for Prenatal Diagnosis of Complex Congenital Heart Defects
Authors: Daniel Ryd, Katrin Fricke, Misha Bhat, Håkan Arheden, Petru Liuba, Erik Hedström
Journal: JAMA Network Open (2021)

<h3>Importance</h3> Prenatal diagnosis of complex congenital heart defects reduces mortality and morbidity in affected infants. However, fetal echocardiography can be limited by poor acoustic windows, and there is a need for improved diagnostic methods. <h3>Objective</h3> To assess the clinical utility of fetal cardiovascular magnetic resonance imaging in cases in which fetal echocardiography could not visualize all relevant anatomy. <h3>Design, Setting, and Participants</h3> This cohort study was conducted between January 20, 2017, and June 29, 2020, at Skåne University Hospital (Lund, Sweden), a tertiary center for pediatric cardiology and thoracic surgery. Participants were fetuses referred for fetal cardiovascular magnetic resonance examination by a pediatric cardiologist after an inconclusive echocardiograph. <h3>Exposures</h3> Fetal cardiovascular magnetic resonance examination requested by the patient's pediatric cardiologist. <h3>Main Outcomes and Measures</h3> Any change in patient management because of diagnostic information gained from fetal cardiovascular magnetic resonance imaging. <h3>Results</h3> A total of 31 fetuses underwent cardiovascular magnetic resonance examination at a median gestational age of 36 weeks (range, 31-39 weeks). Overall, fetal cardiovascular magnetic resonance imaging had clinical utility, affecting patient management and/or parental counseling in 26 cases (84%). For aortic arch anatomy including signs of coarctation (20 fetuses), fetal cardiovascular magnetic resonance imaging added diagnostic information in 16 cases (80%). For assessment of univentricular vs biventricular outcome in borderline left ventricle, unbalanced atrioventricular septal defect, and pulmonary atresia with intact ventricular septum (15 fetuses), fetal cardiovascular magnetic resonance imaging visualized intracardiac anatomy and ventricular function, allowing assessment of outcome in 13 cases (87%). In 4 fetuses with hypoplastic left heart syndrome, fetal cardiovascular magnetic resonance imaging helped delivery planning in 3 cases (75%). Finally, fetal cardiovascular magnetic resonance imaging provided valuable information for parental counseling in 21 cases (68%). <h3>Conclusions and Relevance</h3> In this cohort study, fetal cardiovascular magnetic resonance imaging added clinically useful information to what was available from echocardiography. These findings suggest that fetal CMR has the potential to affect clinical decision-making in challenging cases of congenital heart defects with inconclusive data from echocardiography. Fetal cardiovascular magnetic resonance imaging showed an association with clinical decision-making, including mode of delivery and early postnatal care, as well as with parental counseling.
Comparative studies of atrial and ventricular myosin from normal, thyrotoxic, and thyroidectomized rabbits.
Authors: S KBanerjee
Journal: Circulation Research (1983)

Changes in enzymatic and structural properties of ventricular myosin in thyrotoxic rabbit hearts have been investigated extensively. However, there is little information regarding the effect of thyroid hormone on the atrial myosin. In this study, we have compared enzymatic and structural changes of ventricular and atrial myosin from euthyroid, hypothyroid, and hyperthyroid rabbits. In euthyroid rabbits, Ca++- and actin-activated ATPase activities of atrial myosin were 2-fold greater than those of the ventricular myosin. The Ca++- and actin-activated ATPase activities of atrial myosin from hypothyroid and hyperthyroid rabbits were identical with the values for atrial myosin from euthyroid rabbits. The same ATPase activities of ventricular myosin decreased in hypothyroid hearts but increased in hyperthyroid rabbits. The K+ (EDTA)-ATPase activities of all myosins were the same, irrespective of the thyroid status of the animal. Pyrophosphate-polyacrylamide gel electrophoresis patterns showed two isoenzymes (d...
TREND Reporting Guidelines for Nonrandomized/Quasi-Experimental Study Designs
Authors: Alex B. Haynes, Jason S. Haukoos, Justin B. Dimick
Journal: JAMA Surgery (2021)

This Guide to Statistics and Methods summarizes the use, required items, and limitations of the Transparent Reporting of Evaluations with Nonrandomized Designs (TREND) reporting guidelines for nonrandomized/quasi-experimental study designs.
Selective enhancement of function of stunned myocardium by increased flow.
Authors: L DStahl, T RAversano, L CBecker
Journal: Circulation (1986)

Although augmentation of flow does not improve the performance of normal myocardium, the hyperemic response after brief coronary occlusion is associated with transient hyperfunction in the previously ischemic region. In this study we assessed the effect of vasodilator-enhanced coronary blood flow on the systolic function of postischemic stunned myocardium. In 18 open-chest, anesthetized dogs the anterior descending artery was occluded for 5 min, followed by a 10 min period of reflow, repeated 12 times with a final 90 min recovery period. After the recovery period, either 0.06 mg/min dipyridamole (n = 6), 1 mg/min papaverine (n = 6), or 1.5 micrograms/kg/min nitroglycerin (n = 6) was infused intravenously for 15 min. Regional myocardial blood flow, which had returned to normal before administration of vasodilator, was increased 150% above baseline by dipyridamole and 80% by papaverine, but was unchanged by nitroglycerin. Segmental shortening decreased after repeated occlusions: from 17.5% to 0.9% in the gr...
Is The Decline In Acute Upper Gastrointestinal Bleeding Associated With The Lockdown During Pandemic Period Of COVID-19?
Authors: M Živković, I Budimir, V Ratkajec, D Bakula, I Budimir jr, A Ratković, M Nikolić
Journal: Endoscopy (2021)

Aims The aim of this prospective cohort trial is to show the change trend of clinical, epidemiological and endoscopic characteristics of upper gastrointestinal bleeding (UGIB) during the "lockdown" pandemic (COVID -19) compared to pandemic-free period.
Mortality from Pulmonary Hypertension in the Pediatric Cardiac ICU
Authors: Emily Morell, Michael Gaies, Jeffrey R. Fineman, John Charpie, Rohit Rao, Jun Sasaki, Wenying Zhang, Garrett Reichle, Mousumi Banerjee, Sarah Tabbutt
Journal: American Journal of Respiratory and Critical Care Medicine (2021)

Rationale: Patients with pulmonary hypertension (PH) admitted to pediatric cardiac ICUs are at high risk of mortality. Objectives: To identify factors associated with mortality in cardiac critical care admissions with PH. Methods: We evaluated medical admissions with PH to Pediatric Cardiac Critical Care Consortium institutions over 5 years. PH was standardly defined in the clinical registry by diagnosis and/or receipt of intensive care–level pulmonary vasodilator therapy. Multivariable logistic regression identified independent associations with mortality. Measurements and Main Results: We analyzed 2,602 admissions; mortality was 10% versus 3.9% for all other medical admissions. Covariates most strongly associated with mortality included invasive ventilation (adjusted odds ratio, 44.8; 95% confidence interval, 6.2–323), noninvasive ventilation (19.7; 2.8–140), cardiopulmonary resuscitation (8.9; 5.6–14.1), and vasoactive infusions (4.8; 2.6–8.8). Patients receiving both invasive ventilation and vasoactive infusions on admission Days 1 and 2 had an observed mortality rate of 29.2% and 28.6%, respectively, compared with <5% for those not receiving either. Vasoactive infusions emerged as the dominant early risk factor for mortality, increasing the absolute risk of mortality on average by 6.4% when present on admission Day 2. Conclusions: Patients with PH admitted to pediatric cardiac critical care units have high mortality rates. Those receiving invasive ventilation and vasoactive infusions on Day 1 or Day 2 had an observed mortality rate that was more than fivefold greater than that of those who did not. These data highlight the illness severity of patients with PH in this setting and could help inform conversations with families regarding the prognosis.
Pulmonary vasodilator responses to catecholamines and sympathetic nerve stimulation in the cat. Evidence that vascular beta-2 adrenoreceptors are innervated.
Authors: A LHyman, PNandiwada, D SKnight, P JKadowitz
Journal: Circulation Research (1981)

We investigated the effects of catecholamines and sympathetic nerve stimulation in the feline pulmonary vascular bed under conditions of controlled pulmonary blood flow. Norepinephrine and nerve stimulation caused dose- and stimulus frequency-dependent increases in pulmonary vascular resistance. However, when pulmonary vascular tone was enhanced and alpha receptors blocked, norepinephrine and nerve stimulation caused dose- and frequency-dependent decreases in pulmonary vascular resistance. The decreases in pulmonary vascular resistance were blocked with propranolol and were of greater magnitude than were constrictor responses observed under basal conditions. Vasodilator responses to nerve stimulation were not modified by atropine. Epinephrine and isoproterenol had marked vasodilator activity in the pulmonary vascular bed when pulmonary vascular tone was elevated. When alpha receptors were blocked, isoproterenol and epinephrine had similar vasodilator activity, and when beta receptors were blocked, epineph...
Ventricular function before and after direct revascularization surgery. A proposal for an index of vascularization to correlate angiographic and ventriculographic findings.
Authors: J ALevine, D JBechtel, P FCohn, M VHerman, RGorlin, L HCohn, J JCollins
Journal: Circulation (1975)

In order to determine the effect of direct bypass surgery on the total coronary arterial supply to the heart, a numerical construct was devised to incorporate the development of new obstructive lesions and the presence of patent or nonpatent grafts. This construct, termed a vascularization index (VI), was used to evaluate left ventricular function and anginal symptoms after coronary artery bypass surgery in 56 patients. Patients with an increase in local or total arterial blood supply (positive delts VI) often had similar directional changes in segmental wall motion and ventricular ejection fraction. Patients with a decrease in local or total arterial blood supply (negative delta VI), due to either nonpatent grafts or progression of atherosclerotic disease, also usually had similar directional changes in segmental wall motion and ventricular ejection fraction. (Although nearly all patients reported a decrease in anginal symptoms after surgery, delta VI could not identify degree of improvement.) Use of an ...