bluuebunny/crossref_metadata_2025_split huggingface dataset:
Assessing the Physiologic Significance of Coronary Artery Disease: Role of Doppler Methodology
Authors: Schlaifer Jay D. , Hill James A. 
Published: February 2009

AbstractIt is important to define both anatomic and functional significance of coronary artery stenoses. Quantitative angiography has decreased the inter‐ and intraobserver variability in interpreting the coronary angiogram, but it is less clinically applicable in assessing functional significance. The coronary Doppler catheter and guidewire can provide considerable information regarding the functional effects and patho‐physiology of coronary stenosis in humans at the time of cardiac catheterization. Clinically, it is a simple and safe technique which makes it feasible in a clinical setting to use it as a tool to assess the physiologic significance of an intermediate stenosis or the functional result of an interventional procedure. Other uses for the intravascular Doppler method, such as the evaluation of cardiac transplant vasculopathy and rejection and evaluation of patients with chest pain syndromes and normal coronary angiograms, are being studied. However, the usefulness of this technique in decision‐making has yet to be fully clarified. Future clinical studies should be directed toward comparing this method with noninvasive methods, that is, exercise treadmill test and thallium studies, and attempt to answer questions regarding its prognostic value.
Atrial fibrillation in acute myocardial infarction: A prospective study based on data from a consecutive series of patients admitted to the coronary care unit
Authors: Madias John E. , Patel Dilip C. , Singh Deovrat 
Published: February 2009

AbstractAtrial fibrillation (AF) is a common and much‐studied arrhythmia in patients with acute myocardial infarction (MI). However, documentation of its occurrence in temporal association with MI has been often neglected in the literature; also, its frequent occurrence with mere advanced age, or in the setting of various cardiac conditions or complications, has prevented the definition of an exact role for AF as a marker or determinant of outcome in patients with ML The purpose of this study was to evaluate prospectively the frequency of AF (present or occurring subsequently) in a consecutive series of patients with MI admitted to the Coronary Care Unit, and to explore for variables associated with this arrhythmia; the role of AF in determining major clinical outcomes of the patients was also examined. A large data base of baseline, clinical, laboratory, and patient outcome variables was generated and continuously updated to examine correlates of AF and its possible role in determining prognosis. AF was found in 72 of 517 patients, of whom 58 experienced this arrhythmia anew. Univariate analyses detected a positive association of AF with age, pulmonary congestion, left ventricular hypertrophy, high admission Killip class, and a large array of complications including in‐hospital mortality. Multivariate analyses showed, however, that AF correlated weakly with age and strongly with left ventricular hypertrophy and occurrence of ventricular tachycardia, but that it was not a determinant of ventricular fibrillation or in‐hospital mortality.
Change of plasma leukotriene c4 during myocardial ischemia in humans
Authors: Takase Bonpei , Kurita Akira , Maruyama Toshiharu , Uehata Akimi , Nishioka Toshihiko , Mizuno Kyoichi , Nakamura Haruo , Katsura Kenichiro , Kanda Yoshikazu 
Published: February 2009

AbstractChanges in leukotriene C4 levels during different degrees of myocardial ischemia in humans were examined by comparing radioimmunoassay measures of leukotriene C4 plasma levels obtained during transient and prolonged myocardial ischemia. Leukotriene C4 levels in systemic arterial and coronary sinus blood were determined in patients with chronic stable angina before and after myocardial ischemia induced either by exercise (supine bicycle ergometer exercise stress testing; n = 14; age, 52 ± 8 years) or by coronary occlusion during angioplasty (n = 14; age 53 ± 7 years). Temporal changes of leukotriene C4 were also followed in arterial and pulmonary artery blood within 24 h after the onset of chest pain (acute phase), and 1 day, 1 week, and 1 month later in 22 patients with acute myocardial infarction (AMI) (12 patients with thrombolytic therapy, age 61 ± 10 years; 10 patients without thrombolytic therapy, age 60 ± 11 years). Clinical characteristics, including coronary risk factors and the severity of coronary artery disease, were not significantly different among the groups. Exercise‐induced myocardial ischemia and coronary occlusion did not induce any significant leukotriene C4 changes in the chronic stable angina patients, whereas AMI patients had significantly higher plasma leukotriene C4 levels in both arterial and pulmonary artery blood in the acute phase compared with those of chronic stable angina patients (arterial blood, 471 ± 164 pg/ml and 477 ±235 pg/ml vs. 275 ± 254 pg/ml or 240 ± 66 pg/ml, p< 0.05; pulmonary artery blood in AMI, 543 ± 162 pg/ml vs. 234 ± 125 pg/ml or 225 ±64 pg/ml, coronary sinus blood in chronic stable angina, p < 0.05). These results suggest that leukotriene C4 is involved more in prolonged myocardial ischemia than in transient myocardial is chemia, and that leukocyte function might play a significant role in the pathogenesis of patients with AMI.
Stress‐induced hemodynamic and hemostatic changes in patients with systemic hypertension: Effect of verapamil
Authors: Gebara Otavio C. E. , Jimenez Alfredo H. , Mckenna Carol , Mittleman Murray A. , Xu Ping , Lipinska Izabella , Muller James E. , Tofler Geoffrey H. 
Published: February 2009

AbstractStress‐induced hemodynamic and hemostatic responses may acutely trigger atherosclerotic plaque disruption and thrombosis leading to myocardial infarction. This study was designed to evaluate the responses to three stressors and to determine if once‐daily sustained release verapamil (Verelan®) modified these responses. We studied 13 patients with mild to moderate hypertension in a randomized, double‐blind, placebo‐controlled crossover trial. After 4 weeks of therapy, patients were evaluated following assumption of the upright posture, mental stress, and cold pressor test. During placebo, the stressors produced an increase in systolic pressure (144 ± 2 to 167 ± 3 mmHg, p < 0.001), heart rate (70 ± 2 to 77 ± 2 beats/ min, p< 0.001), and platelet aggregability to adenosine diphosphate (threshold concentration fell from 2.8 ± 0.4 to 1.9 ± 0.1 μM, p = 0.05)and epinephrine (3.4±0.9 to 1.6 ±0.6 μM, p < 0.001). Verapamil lowered systolic pressure at baseline (144 ± 2 to 134 ± 2 mmHg, p < 0.001), and after stress (167 ± 3 to 154 < 3 mmHg, p < 0.001), but did not alter the absolute increase with stress. During verapamil, platelet reactivity did not increase with stress, and the post‐stress response to epinephrine was reduced (higher threshold concentration) compared with placebo (3.9 ± 1.3 vs. 1.5 ± 0.3 μM, p = 0.05). Verapamil also reduced the response to collagen (increased lag time) at baseline and after stress (111 ± 9 vs. 91 ± 3 s, p < 0.01). We conclude that verapamil blunted potentially harmful stress‐induced hemodynamic and hemostatic changes. Further studies are required to determine whether these effects translate into a lower incidence of acute cardiovascular events.
Transesophageal echocardiography in the detection of inferior vena cava and cardiac metastasis in hepatocellular carcinoma
Authors: Tse Hung‐Fat , Lau Chu‐Pak , Lau Yuk‐Kong , Lai ChinL‐gung 
Published: February 2009

AbstractAntemortem diagnosis of inferior vena cava (IVC) and cardiac metastasis of hepatocellular carcinoma (HCC) is difficult but important before consideration of curative resection. There are only a few cases of cardiac metastasis of HCC which have been diagnosed antemortem by echocardiography. Accordingly, 18 consecutive patients with HCC who were potential candidates for curative resection were studied by transthoracic (TTE) and transesophageal echocardiography (TEE). One (6%) and two (11%) patients had cardiac and IVC metastasis of HCC, respectively, which was detected by two‐dimensional TTE. In contrast, by using TEE, four patients (22%) showed tumor invasion of the IVC, of whom two (11%) had tumor mass extending into the right atrium (RA). There was no significant difference in age, serum level of alpha‐fetoprotein, and percentage of right liver lobar involvement between those with and without cardiac metastasis. Patients without cardiac metastasis detected on TTE or TEE had significantly longer mean duration of survival (5.0 ±2.1 vs. 2.1 ± 1.0 months; p < 0.05). In summary, TEE may be more useful than TTE in the detection of cardiac metastasis of HCC, which occurred in 22% of patients whose primary tumor was considered to be surgically resectable in our series. This can be safely performed in patients with HCC and can provide optimal visualization of the IVC and RA. The high prevalence of subclinical cardiac metastasis in HCC mandates the use of TEE in all patients with HCC prior to surgical intervention.
Reproducibility of head‐up tilt test in patients with syncope
Authors: Ruiz Graciela A. , Scaglione Jorge , González‐Zuelgaray Jorge 
Published: February 2009

AbstractAs the head‐up tilt test (HUT) is employed to verify the efficacy of undertaking a treatment, we prospectively evaluated the reproducibility of positive and negative results, as well as that of the response type in 64 consecutive patients (mean age 34.6 ± 22.9 years) with syncope of unknown cause. Two HUTs (60 min, 75° ), separated by an interval of 9.77 ± 8.21 days, were performed on each patient. Positive responses were reproduced in the second HUT in 54.5% of the patients. A greater reproducibility (84.3%) was observed for negative responses. Of the 31 patients with a negative first test, 5 had a positive response during the second HUT. Using a multivariate analysis, no clinical variable correlated with the reproducibility of positive or negative results. Likewise, neither arterial pressure nor heart rate observed during the test were correlated with reproducibility. Of 18 patients who reproduced positive responses, 12 (66.6%) did so with the same response modality. In three patients with documented monomorphic sustained ventricular tachycardia, which was hemodynamically well tolerated, and in one patient with temporal spike wave activity in the electroencephalogram, HUT was also positive. It was concluded that the low reproducibility of HUT limits its usefulness as a tool for evaluating treatment efficacy. The variability of the type of response suggests a common mechanism leading to cardioinhibitory and vasodepressor reactions. A positive result in only the second study shows the rationale of performing two tests when the first one is negative.
Peripheral artery recanalization in humans using balloon and laser angioplasty
Authors: Barbeau Gérald R. , Seeger James M. , Kaelin Lawrence D. , Abela George S. , Jablonski Sharon , Friedl Stephan E. 
Published: February 2009

AbstractThe treatment of patients with complex peripheral arterial disease and those who have had previous unsuccessful attempted revascularization procedures can be clinically challenging. Initial treatment was begun using therapy by percutaneous balloon and laser angioplasty, then proceeding to bypass surgery if severe ischemia persisted. Both percutaneous and cut‐down approaches were used to access totally occluded arteries. An attempt was made to cross the occlusion mechanically with either a guide wire or an activated laser probe. If laser recanalization was not successful, the patient underwent bypass surgery or was managed with medication unless an amputation was necessary. Following initial screening of 381 patients, 115 procedures were performed on 103 patients. In 31 procedures (28 patients), only balloon angioplasty was performed. In 84 procedures (75 patients), laser recanalization was attempted: 55 percutaneously and 29 by cut‐down. Overall technical success (crossing the obstruction without perforation) was 86/115 (75%). Technically successful procedures were characterized by shorter arterial occlusions than were technical failures (8.4 ± 1 cm vs. 14.3 ± 1.9 cm; p< 0.004). Clinical success (residual stenosis < 50%, symptom relief, improved ankle brachial index ≥ 0.15, and no complications) was achieved in 22/31 (71 %) of balloon angioplasty procedures alone. The stenoses decreased from 98 ± 4% to 31 ± 24%, p < 0.00001. Combined percutaneous laser and balloon angioplasty had a technical success of 36/55 (65%). Stenoses were reduced from 99 ± 2% to 56 ± 14% after laser angioplasty, to 30 ± 15% after balloon angioplasty, p < 0.0001. Laser angioplasty performed via a cut‐down had a clinical success of 9/29 (31%). However, major complications were rare. Device staging for treatment of peripheral vascular disease provides additional options for patients who are at high surgical risk and/or in whom standard therapy has failed.
Endocardial fibroelastosis and primary carnitine deficiency due to a defect in the plasma membrane carnitine transporter
Authors: Bennett Michael J. , Hale Daniel E. , Pollitt Rodney J. , Variend Sadick , Stanley Charles A. 
Published: February 2009

AbstractEndocardial fibroelastosis (EFE) has previously been shown to be associated with tissue carnitine deficiency, although the basis for the carnitine deficiency has not been documented. A patient with the classical features of EFE and marked deficiency of carnitine in heart muscle, skeletal muscle, and liver is presented in this report. Cultured skin fibro‐blasts from both parents demonstrated levels of carnitine uptake at 50% of the normal rate. This is consistent with het‐erozygosity for the plasma membrane carnitine transporter defect, indicating likely homozygosity for this recently recognized inborn error in the index patient.
Anomalous origin of the right coronary artery from the pulmonary trunk: Is surgical reimplantation into the aorta a method of choice?
Authors: Kautzner Josef , Veselka Josef , Rohac Jan 
Published: February 2009

AbstractThe origin of the right coronary artery (RCA) from the pulmonary trunk (PT) is a rare congenital anomaly. Although most of the patients remain asymptomatic, prophylactic reimplantation of the RCA into the aorta has been recommended to prevent an adverse outcome. The report describes postoperative results in two patients following uneventful RCA reimplantation. A 47‐year‐old man, with coexisting diffuse atherosclerotic involvement of the left coronary artery, remained symptomatic despite the establishment of a two‐coronary system. The second patient, a 36‐year‐old woman, with isolated anomalous origin of the RCA from the PT, continued to present with myocardial ischemia on exertion. The original observation of an angiographic “slow‐flow” phenomenon in the reimplanted RCA in both patients implies the impairment of myocardial microvessels. These findings give rise to the question of whether the reimplantation of the anomalous artery is really superior to simple ligation of its origin in order to relieve the “coronary steal” effect.
Antiplatelet and anticoagulant use after myocardial infarction
Authors: Almony Gregory T. , Lefkovits Jeffrey , Topol Eric J. 
Published: February 2009

AbstractCoronary thrombosis leading to myocardial infarction is a complex process involving the interaction of the arterial wall, the coagulation cascade, and platelets. Increased understanding of the molecular biology of thrombosis has prompted an evolution in antithrombotic therapy, from the early use of warfarin following myocardial infarction to agents targeting specific receptors or modulators in the thrombotic process. The complexity of thrombosis allows for numerous sites of pharmacologic intervention the multiple pathways leading to platelet aggregation and thrombin formation provide the opportunity for combined therapies. This review presents the current clinical data on antiplatelet, anticoagulant, and specific antithrombin therapies following myocardial infarction.
Symptoms of hypertrophic cardiomyopathy, with special emphasis on syncope and postprandial exacerbation of symptoms
Authors: Gilligan David M. , Nihoyannopoulos Petros , Sbarouni Eftichia , Dritsas Athanase , Oakley Celia M. , Fletcher Astrid 
Published: February 2009

AbstractWe undertook a prospective study of the symptoms of hypertrophic cardiomyopathy with the aim of profiling symptomatic morbidity in detail, determining the prevalence of anxiety and depression, and describing the prevalence and associations of syncope and postprandial symptom exacerbation. A questionnaire was administered to consecutive outpatients;70 with hypertrophic cardiomyopathy, 43 with coronary artery disease, 32 with idiopathic dilated cardiomyopathy, and to 40 normal subjects. Hypertrophic cardiomyopathy patients underwent exercise testing, echo‐cardiography, and Holter monitoring. Hypertrophic cardiomyopathy patients had a high frequency of cardiac symptoms and, on average, had a level of symptomatic morbidity equivalent to that of chronic stable angina and dilated cardiomyopathy. There was no evidence for an excess of anxiety (14%) or depression (6%) in patients with hypertrophic cardiomyopathy. Syncope and presyncope, especially provoked by exertion or posture change, were characteristic and common symptoms in hypertrophic cardiomyopathy. A history of syncope was associated with an abnormal blood pressure response to exercise in over 50% of cases that may be the mechanism of syncope in some. Postprandial exacerbation of symptoms occurred in over one‐third of hypertrophic cardiomyopathy patients, half of coronary disease patients, and infrequently in dilated cardiomyopathy. Hypertrophic cardiomyopathy patients with postprandial symptoms had a greater frequency of angina, were more symptomatic, and had a reduced exercise capacity, suggesting that postprandial symptoms are a marker for more severe disease.
Acute infarction of the left ventricular papillary muscle: Electrocardiographic pattern and recognition of its location
Authors: Dabrowska Barbara , Prejs Robert , Zdzienicki Marcin , Walczak Ewa 
Published: February 2009

AbstractBackground and hypothesis: ST‐segment depression during acute myocardial infarction (AMI) is known to herald serious hemodynamic complications. Since the mechanism of this dependence is not clear, we reinvestigated the old concept of papillary muscle infarction (PMI) as a cause of marked ST depression.Methods: Autopsies and morpho‐electrocardiographic correlations were performed in 53 patients with AMI involving one or both left ventricular papillary muscles, and in 10 patients with AMI, but without acute PMI.Results: ST‐segment depression ≥l mm in at least two leads (mean 3.6 ± 2.2 mm) was found in 46 (86.8%) patients with, and in one without acute PMI. Thus, the sensitivity and specificity in selecting patients with acute PMI from among those with AMI were 86.8 and 90%, respectively, with an overall accuracy of diagnosis of acute PMI in the course of AMI of 87.3%. Among 26 patients with ST elevation consistent with diagnosis of AMI, ST depression, recorded in 22 patients, was insignificantly greater than in 24 of 27 patients without ST elevation: 4.1 ± 2.9 versus 3.1 ± 1.2 mm. Localization of ST depression in the limb leads allowed recognition of which papillary muscle suffered from acute infarction: ST depression in the inferior leads was seen only in patients with anterolateral PMI, whereas in leads I and/or aVL it was seen only in cases with posteromedial PMI. This rule was also valid in patients without concomitant ST elevation.Conclusion: Patients with acute PMI show marked ST‐segment depression. Its location in the limb leads allows recognition of which papillary muscle has undergone necrosis. This cause of marked ST depression in patients with AMI may explain the high mortality in this particular group.
Intravenous propafenone in paroxysmal atrial fibrillation: A randomized, placebo‐controlled, double‐blind, multicenter clinical trial
Authors: Fresco Claudio , Proclemer Alessandro , Pavan Alessandro , Buia Gianfranco , Vicentini Alfredo , Pavan Daniela , Morgera Tullio ,   on behalf of the Paroxysmal Atrial Fibrillation Italian Trial (PAFIT)‐2 Investigators
Published: February 2009

AbstractBackground: Pharmacological conversion of paroxysmal atrial fibrillation is frequently necessary. The aim of this study was to compare intravenous propafenone, a class Ic antiar‐rhythmic agent, with placebo in paroxysmal atrial fibrillation (AF) of recent onset (<72 h).Patients and methods: We randomly allocated 75 patients, aged 18 to 70 years, with paroxysmal AF to receive intravenous propafenone (2 mg/kg in 15 min followed by 1 mg/kg in 2 h) or the matching placebo. Patients were followed for 3 h. Exclusion criteria were the presence of one of the following: clinical heart failure, recent acute myocardial infarction, hypotension, atrioventricular block, Wolff‐Parkinson‐White syndrome, or current treatment with antiarrhythmic agents or digitalis.Results: No sign of heart disease was found in 74.7% of the patients. Echocardiographically determined left atrium diameter was similar in the two groups. Conversion to sinus rhythm occurred in 24 of 41 patients allocated to propafenone and in 10 of 34 patients allocated to placebo (odds ratio 3.2, 95% confidence intervals 1.3‐7.9;p<0.01). Mean conversion time was 34 ± 29 and 71 ± 55 min, respectively, for propafenone and placebo. Mean heart rate in nonconverters decreased from 146 to 109 beats/min in patients treated with propafenone while it remained virtually unchanged in those treated with placebo. Only minor side effects were noted.Conclusions: Intravenous propafenone is an effective therapeutic option for restoring sinus rhythm in patients with paroxysmal AF of recent onset.
Correlation between left ventricular contractility and relaxation in patients with idiopathic dilated cardiomyopathy
Authors: Kato Ryozo , Ishihara Hitoshi , Sobue Toshikazu , Yokota Mitsuhiro 
Published: February 2009

AbstractBackground and hypothesis: It is not fully understood whether alterations in left ventricular (LV) relaxation in patients with idiopathic dilated cardiomyopathy (DCM) precede or follow alterations in LV systolic function. Accordingly, we investigated the relationship between LV systole and diastolic relaxation in patients with DCM using LV pressure‐volume analysis.Methods: Hemodynamic data were collected for 38 consecutive patients with DCM in normal sinus rhythm and in the resting steady state (New York Heart Association functional class II to III). Continuous simultaneous pressure‐volume relationships were obtained by conductance catheter. Left ventricular end‐systolic elastance (Ees) was determined during transient occlusion of the inferior vena cava.Results: Left ventricular ejection fraction, peak negative dP/dt, and peak positive dP/dt were depressed (31 ± 11%, ‐ 1242 ± 351 mmHg/s, and 1118 ±253 mmHg/s, respectively ). The LV end‐diastolic volume index, the time constants of isovolumic LV pressure decay Tl and Td were increased (141 ±38 ml/m2, 54+14 ms, and 69 ± 17 ms, respectively). Ees was markedly depressed (0.9 ± 0.5 mmHg/ml) and was not correlated with established systolic or diastolic indices except for peak positive dP/dt. Our results showed that abnormalities of relaxation were not correlated with contractile dysfunction in patients with DCM in the resting steady state however, most patients (79%) had both prolonged relaxation and extremely depressed contractility. Abnormal relaxation may have been transient or compensated in some patients (21%) with DCM who had preserved relaxation despite severely depressed contractility.