bluuebunny/crossref_metadata_2025_split huggingface dataset:
Enzymatic analysis and collagen content in endomyocardial biopsy samples of patients with congestive cardiomyopathy of unknown etiology
Authors: Schultheiss H. P. , Bolte H. D. , Fischer S. , Cyran J. 
Published: February 2009

AbstractEndomyocardial biopsy samples from patients suffering from congestive cardiomyopathy of unknown etiology (COCM) were analyzed for lactate dehydrogenase (LDH) isoenzyme distribution by microisoelectric focusing. In addition, the concentration of collagen in the biopsy samples was estimated by determination of hydroxyproline and proline. The results were correlated with the clinical and hemodynamic data of the patients.Increased activities of total LDH and LDH5— the worse the hemodynamic parameters, the higher the concentration of LDH5— indicate an enhanced anaerobic glycolysis in the myocardium of COCM patients. The close correlation between the hemodynamic data and the LDH isoenzyme pattern suggests an association between severity of COCM and impairment of aerobic metabolism. The results of the alteration in the LDH isoenzyme pattern were not influenced by the collagen content in the myocardial biopsy samples.Varying isoenzyme patterns in the different parts and wall layers of the normal heart show the necessity of analyzing biopsy samples only from comparable localizations.
Evaluation of diuretic therapy by impedance cardiography in acute myocardial infarction
Authors: Gabriel S. , Ekelund L. G. , OrÖ L. 
Published: February 2009

AbstractChanges in transthoracic electrical impedance (TEI) were recorded in 20 patients with acute myocardial infarction before, during, and 60 min after intravenous administration of furosemide (Impugan®). The major change was an increase in TEI (Z0) (6.2%, p<0.001). The mean impedance stroke volume (n = 10) decreased by 7.8% (p<0.05) while the mean impedance cardiac output (n = 10) decreased by 6.3% (p>0.05). Heart rate and blood pressure remained unchanged. It was possible to differentiate between two types of TEI changes after furosemide. In 10 patients there was an early and rapid increase in Z0 (type A), while the rest of the patients showed a decreased or unchanged Z0 followed by a slow increase (type B). The line describing the mean Z0 change in type A was significantly higher than that of type B and fell outside ±2 SEM of the line describing the mean Z0 change found in five normal subjects (type C). The Z0 change in type B was similar to that in type C. It is assumed that Z0 change in type A may represent patients with an increased amount of extravascular fluid (heart failure), while the change in type B represents patients without heart failure. This assumption is based on the difference in dependency of TEI on extravascular volume versus intravascular volume changes. It is suggested that the impedance method may be used as a simple noninvasive method to assess the effect of diuretic therapy and may have the value of detecting extravascular thoracic fluids in acute myocardial infarction.
Comparative effects of intravenous dipyridamole and sublingual nitroglycerin on coronary hemodynamics and myocardial metabolism at rest and during atrial pacing in patients with coronary artery disease
Authors: Arrotti J. , Gunnar R. M. , Ward J. , Loeb H. S. 
Published: February 2009

AbstractThe effects of intravenous dipyridamole (20 mg) and sublingual nitroglycerin (0.6 mg) were compared at rest and during rapid atrial pacing in patients with significant coronary obstruction. Dipyridamole, which had no significant effect on resting systolic blood pressure, caused a significant increase in coronary sinus flow (CSF) and reduction of coronary vascular resistance (CVR) and arterial‐coronary sinus oxygen difference (AO2‐CSO2δ), whereas nitroglycerin reduced resting systolic pressure but had no significant effect on CSF, CVR, or AO2‐CSO2°. Although these effects of dipyridamole and nitroglycerin on resting systolic pressure, CSF, CVR, and AO2‐CSO2° were qualitatively similar during rapid atrial pacing, the onset of chest pain and ischemic ECG changes occurred at a lower heart rate following dipyridamole (136±5 beats/min) than following nitroglycerin (149±6 beats/min, p<0.01). However, maximal double product and myocardial oxygen consumption achieved during pacing were similar following both dipyridamole and nitroglycerin and were less than control pacing values. Coronary dilatation following dipyridamole appears to reduce tolerance to pacing‐induced ischemia probably by maldistribution of coronary flow away from ischemic myocardium. Nitroglycerin differs from dipyridamole by improving tolerance to pacing; however, this difference appears to be due to systemic vasodilator effects of nitroglycerin rather than to enhancement of flow to ischemic myocardium.
The resting cardiokymogram: Distribution of morphologies in normal patients and in patients with coronary heart disease
Authors: Tzivoni D. , Diamond G. A. , Vas R. , Silverberg R. A. , Forrester J. S. 
Published: February 2009

AbstractThe cardiokymograph, a relatively new noninvasive device capable of recording anterior left ventricular segmental wall motion, was used to evaluate the frequency and type of wall motion abnormalities in 25 normal patients and in 109 patients with ischemic heart disease. Of the 25 patients with normal coronary arteries and normal left ventriculograms, 24 had smooth systolic inward motion which morphologically resembles the normal pattern of systolic shortening as measured in experimental animals by various length gauges. In patients with angiographically established coronary artery disease but normal left ventriculograms and no previous myocardial infarction (MI), systolic outward motion was significantly more common than in normal patients. The most common systolic outward motion pattern seen in this group was partial outward motion characteristic of early stages of myocardial ischemia in experimental animals. In contrast, holosystolic outward motion, characteristic of severe ischemia in animals, was seen most commonly in patients with MI (72% anterior vs. 28% inferior). Thus, holosystolic outward motion was characteristic of MI especially when acute and involving the anterior wall, while partial systolic outward motion was the more common pattern in ischemic heart disease without MI, and systolic inward motion was the pattern most commonly seen in normals.
Controlled study of intravenous nitroglycerin treatment for two days in patients with recent myocardial infarction
Authors: Bussmann W.‐D. , Barthe G. , Klepzig H. , Kaltenbach M. 
Published: February 2009

AbstractHemodynamic measurements were obtained for 48 h in 46 patients with recent myocardial infarction. Patients were randomized to treatment with (n = 22) and without nitroglycerin (NTG) (n = 24). In patients with diastolic pulmonary arterial pressure (PAEDP) <20 mmHg (group I), NTG decreased PAEDP from 15 to 11 mmHg (n = 13); in the untreated control group PAEDP remained unchanged (n = 15). Cardiac output decreased in the NTG group from 5.4 to 5.0 1/min and in the control group from 4.7 to 4.4 1/min. Mean arterial pressure decreased in both groups, in the NTG group from 106 to 97 mmHg and in the control group from 102 to 94 mmHg.In patients with left ventricular failure and PAEDP >20 mmHg (group II) the decrease in left ventricular filling pressure was significantly greater (25 to 17 mmHg, n = 9) than in the control group (24 to 20 mmHg, n = 9). Cardiac output increased during NTG treatment from 4.2 to 5.1 1/min. In the control group, however, cardiac output decreased from 4.2 to 3.6 1/min. Mean arterial pressure decreased from 103 to 95 mmHg in the NTG group and from 114 to 96 mmHg in the control group. Heart rate did not change significantly.Thus, PAEDP decreased significantly in patients who received NTG treatment for 48 h compared to an untreated control group. Cardiac output increased in treated patients, especially those with left ventricular failure, but decreased in the control group. Mean arterial pressure decreased to the same degree in treated patients and in controls.
Pulmonary hypertension in systemic lupus erythematosus: Hemodynamics and effects of vasodilator therapy
Authors: Santini D. , Fox D. , Kloner R. A. , Konstam M. , Rude R. E. , Lorell B. H. 
Published: February 2009

AbstractA case is reported of a 29‐year‐old woman with systemic lupus erythematosus (SLE) who developed clinical manifestations of pulmonary hypertension at a time when other manifestations of SLE were quiescent. She had a restrictive ventilatory defect but clear lung fields on chest x ray. Cardiac catheterization revealed severe pulmonary hypertension. Calculated pulmonary vascular resistance fell slightly after administration of oxygen and during infusion of vasodilators. Symptomatic improvement and a modest increase in right ventricular ejection fraction, as measured by radionuclide ventriculography, were noted following 1 week of oral hydralazine therapy. Clinically significant pulmonary hypertension is a rare complication of SLE and the increased pulmonary vascular resistance may not be entirely fixed. Cardiac catheterization and radionuclide ventriculography may be useful in assessing response to medical therapy.
Atrioventricular sequential pacing in cardiac amyloidosis: An acute doppler echocardiographic and catheterization hemodynamic study
Authors: Mathew Verghese , Chaliki Hari , Nismmura Rick A. 
Published: February 2009

AbstractBackground and hypothesis: Congestive heart failure due to cardiac amyloidosis is often refractory to conventional medical management and is associated with a high mortality rate. Recently, dual‐chamber pacemaker implantation has been proposed as a therapeutic option in the management of patients with certain forms of cardiomyopathy with persistent heart failure symptoms, despite optimal medical therapy. The present study evaluates the acute hemodynamic response to atrioventricular (AV) pacing in patients with cardiac amyloidosis who presented with refractory heart failure symptoms.Methods: Three patients with medically refractory heart failure due to cardiac involvement of amyloidosis underwent a simultaneous cardiac catheterization/Doppler echocardiography study with acute AV sequential pacing at varying AV intervals.Results: During pacing at various AV intervals, all patients showed an increase in their filling pressures and either no change or decline in their cardiac index.Conclusion: The current study demonstrates an absence of acute hemodynamic benefit with AV sequential pacing in patients with amyloid heart disease and medically refractory heart failure symptoms.
Early presentation of dilated cardiomyopathy as a part of seroconversion illness in human immunodeficiency virus infection
Authors: Fath‐Ordoubadi F. , Van Der WATT M. J. , Noble M. I. M. 
Published: February 2009

AbstractIt has been debated whether dilated cardiomyopathy seen in patients with acquired immune deficiency syndrome is caused by the virus itself or by the combination of other factors such as presence of opportunistic pathogens and/or severe immunosuppression. This paper describes the first reported case of a patient with human immunodeficiency virus (HIV) infection presenting with dilated cardiomyopathy during his acute seroconversion illness. Presence of cardiac involvement at a very early stage of HIV infection with no evidence of opportunistic infections, or immunosuppression with high CD4 count indicates that HIV may itself be a cardiac pathogen. This case also illustrates the importance of testing for HIV infection as part of the assessment of any patient presenting with myocarditis or dilated cardiomyopathy.
Evaluation and treatment strategies in patients at high risk of sudden death post myocardial infarction
Authors: Underwood R. Dent , Sra Jasbir , Akhtar Masood 
Published: February 2009

AbstractOver 50 percent of deaths in patients who survive an acute myocardial infarction are due to fatal ventricular tachyarrhythmias. Patients who survive an episode of sustained ventricular arrhythmia are at highest risk of recurrent cardiac arrest. Electrophysiologic studies have been found to be useful in guiding therapy and reducing mortality in these patients and in patients with syncope due to arrhythmic etiology. Evaluation and treatment of nonsustained ventricular tachycardia post infarction remains somewhat controversial. A recently published trial (MADIT), however, showed improved survival with an implanted defibrillator in patients with coronary disease and asymptomatic nonsustained ventricular tachycardia. Asymptomatic patients post infarction at high risk include those who have significant left ventricular dysfunction, late potentials, high‐grade ventricular ectopy, and abnormal heart rate variability. These tests individually, however, have a low positive predictive accuracy. This, combined with the fact that antiarrhythmic drugs are frequently not effective and can be proarrhythmic, leaves the best treatment for these patients uncertain. It is known, however, that beta‐adrenoreceptor blocking agents do reduce mortality after an acute myocardial infarction. Early studies have shown mixed results relating to sudden death and total mortality with amiodarone. To date, no other antiarrhythmic drug has shown benefit, while several have been shown to be harmful. Recent studies have also shown some beneficial effects of angiotensin‐converting enzyme inhibitors, carvedilol, a third‐generation beta‐blocking agent with vasodilator properties, and the angiotensin II receptor antagonist losartan. However, their precise role in reducing sudden death needs to be defined further.
Direct conversion of atrial flutter to sinus rhythm with low‐output, short‐duration transesophageal atrial pacing
Authors: Ajisaka Hidehiko , Hiraki Tatsuro , Ikeda Hisao , Kubara Ichiro , Yoshida Teruhisa , Ohga Masanobu , Imaizumi Tsutomu 
Published: February 2009

AbstractBackground and hypothesis: Transesophageal atrial pacing (TAP) is useful for terminating paroxysmal non‐selfterminating atrial flutter (RAF); however, high output pacing of long stimulus duration causes severe symptoms such as chest pain. The objective of this study was to investigate the effect of low‐output, short‐duration TAP on the conversion of PAF.Methods: We applied low‐output (within 15 mA with a pulse duration of 10 ms), short‐duration (within 4 s) TAP in 31 patients (50±19 years) with PAF. Transesophageal pacing was delivered with 10 pulses of burst pacing at intervals that were 20 ms shorter than those of the flutter wave length. When the conversion was unsuccessful, we delivered 20 pulses of burst pacing.Results: Sixteen patients (52%) were converted directly to sinus rhythm and 12 (38%) to atrial fibrillation. Transesophageal pacing was ineffective in 3 (10%) patients. The duration of atrial flutter, maximum flutter wave amplitude, effective pacing intervals, underlying heart diseases, and cardiac function were not different between patients who had direct conversion to sinus rhythm and those converted to atrial fibrillation. The patients who had direct conversion to sinus rhythm had longer flutter wave cycle lengths than those converted to atrial fibrillation (248 vs. 221 ms, p<0.005). No patient had complications and complained of any symptoms.Conclusion: Low‐output, short‐duration TAP was useful to convert PAF directly to sinus rhythm without side effects.
Relationship between exercise hyperpnea, hemodynamics, and blood gases before and during glyceryl trinitrate infusion in patients with exercise‐induced elevation of pulmonary artery wedge pressure
Authors: Jørgensen Lars H. , Thaulow Erik , Refsum Harald E. 
Published: February 2009

AbstractBackground: The mechanisms underlying the excessive ventilatory response to exercise in patients with cardiac failure are still not fully understood.Hypothesis: This study was undertaken to investigate the mechanisms behind exercise hyperpnea in patients with exercise‐induced left ventricular dysfunction.Methods: In 18 patients, aged 57–82 years, all with atherosclerotic lumbar aorta aneurysm and pulmonary artery wedge pressure (PAWP) >25 mmHg during supine exercise, ventilation (V), central hemodynamics, and arterial and venous blood gases were examined during supine rest and exercise, before and during infusion of glyceryl trinitrate (GTN).Results: Before GTN, exercise PAWP was 32.2 ± 6.1 mmHg and V/V O2 was 33.8 ± 7.7 1/1 (130% of predicted). With GTN, exercise PAWP was markedly reduced to 15.3 ± 3.8 mmHg (p < 0.001), whereas V/V O2 was only marginally reduced to 32.3 ± 3.0 1/1 (124% of predicted) (p<0.05). Exercise physiologic dead space (VD/VT) declined from 0.31 ± 0.16 to 0.26 ± 0.17 (p<0.05), while PaCO2 was reduced from 5.20 ± 0.31 to 5.10 ± 0.24 kPa (p < 0.05). PvO2 and cardiac output (CO), however, were unchanged, below normal.Conclusion: The data show that exercise‐induced hyperpnea was not substantially reduced by rapid normalization of PAWP and could not be related to preservation of normal PaCO2 in the presence of high VD/VT. The persistence of exercise hyperpnea and reduced PvO2 after GTN is consistent with augmented ventilatory stimuli from hypoxia‐induced metabolic abnormalities in the skeletal muscles, or/and persistently reduced CO, due to changes in the integrated superior command of ventilation and circulation.
Quantitative evaluation of blood row distribution to exercising and resting skeletal muscles in patients with cardiac dysfunction using whole‐body thallium‐201 scintigraphy
Authors: Wada Osamu , Asanoi Hidetsugu , Miyagi Kyoko , Ishizaka Shinji , Kameyama Tomoki , Ishise Hisanari , Inoue Hiroshi , Seto Hikaru 
Published: February 2009

AbstractBackground and hypothesis: Decreased blood flow to working muscles makes an important contribution to exercise intolerance in patients with chronic heart failure. This study was undertaken to examine whether maldistribution of skeletal muscle blood flow is closely related to exercise intolerance in patients with cardiac dysfunction.Methods: Whole‐body thallium scintigraphy was performed during one‐leg exercise in 11 patients with left ventricular (LV) dysfunction (LV ejection fraction <45%). Blood flow distribution to the exercising and resting legs was quantified by expressing regional thallium counts as a percentage of the whole‐body counts at rest, at the level of anaerobic threshold, and at peak exercise.Results: At anaerobic threshold, the thallium activity of exercising muscle increased from 4.2 ± 0.7 to 14.0 ± 2.5% (p< 0.05) in the thigh and from 1.7 ± 0.3 to 4.1 ± 0.9% (p<0.05) in the calf, compared with the resting value. Consequently, the ratio of thallium activity between exercising and resting legs increased to 2.7 ± 0.7 (p<0.05) in the thigh and to 2.3 ± 0.7 (p < 0.05) in the calf. When plotted as a function of anaerobic threshold, thallium activity of the exercising thigh (r = 0.78, p<0.05) and the thallium ratio between exercising and resting thigh (r = 0.69, p<0.05) declined with the reduction of exercise tolerance. These correlations were not observed in calves.Conclusion: Whole‐body thallium scintigraphy demonstrated a maldistribution of leg blood flow in patients with reduced aerobic exercise capacity, suggesting that this abnormality could play an important role in exercising intolerance in these patients.
Cardiac repolarization interval in end‐stage diabetic and nondiabetic renal disease
Authors: Kirvelä Maija , Toivonen Lauri , Lindgren Leena 
Published: February 2009

AbstractBackground and hypothesis: QT interval length is influenced by autonomic nervous activity. In patients with diabetic autonomic neuropathy, both prolongation and shortening of ventricular repolarization has been reported. We studied diabetic and nondiabetic uremic patients to assess the effects of autonomic neuropathy on QT interval length.Methods: 24‐hour electrocardiogram recordings were performed in 12 diabetic and 11 nondiabetic renal transplantation patients, and in 12 control patients. Mean and corrected QT interval (QTc) during the 24‐h period and intervals at predetermined heart rates at day and night periods were determined. The degree of autonomic neuropathy was assessed with cardiovascular autonomic function tests and measurement of heart rate variability.Results: In the diabetic group, severe autonomic neuropathy was present; in nondiabetic uremic patients, abnormalities were less severe. Mean QTc interval during 24 h was 444 ± 24,447 ± 21, and 442 ± 19 ms in the diabetic and nondiabetic uremic patients, and in the control groups, respectively, without any between‐group difference. QT and QTc interval length did not differ among the groups when measured at heart rates of 70, 80, 90, or 100 beats/min.Conclusions: In patients with autonomic failure caused by diabetes and/or uremia, QT interval length cannot be used as a diagnostic indicator of cardiac autonomic neuropathy.
Which fasting triglyceride levels best reflect coronary risk? evidence from the turkish adult risk factor study
Authors: Onat Altan , Sansoy Vedat , Yildirim Beytullah 
Published: February 2009

AbstractBackground: Association between raised low‐density lipoprotein cholesterol (LDL‐C) levels and high risk for coronary heart disease (CHD) is well established and taken into account in guidelines on coronary prevention.Hypothesis: The relationship between risk for coronary heart disease (CHD) and the levels of fasting plasma triglycerides was studied in the cohort of the Turkish Adult Risk Factor Study, a representative random sample of an adult population.Methods: In 829 men and 907 women aged ≥ 27 years (mean 48.5 ± 11), plasma lipids and lipoproteins were measured by the enzymatic dry method in the postabsorptive state. A sample of values was validated in a reference laboratory. Apoliprotein (apo) A‐I and B were measured by the turbidimetric immunoassay using commercial kits in part of the cohort. Blood pressure and anthropometric measurements were made. Criteria for the diagnosis of CHD were based on history, cardiovascular examination, and Minnesota coding of resting electrocardiograms.Coronary heart disease was diagnosed in about 7% of the subjects. Participants were divided into four categories depending on their triglyceride levels: I = < 100 mg/dl (282 men, 400 women), II = 100–139 mg/dl (204 men, 228 women), III = 140–212 mg/dl (188 men, 180 women), and IV = ≥ 212 mg/dl (155 men, 99 women).Results: After adjustment for age, high‐density lipoprotein (HDL) and low‐density lipoprotein (LDL) cholesterol, smoking, and body mass index by logistic regression analysis, and after assigning the CHD risk of 1 to Category I, the relative risk for men and women combined rose to 1.42 in Category III (p<0.045) while it diminished to 0.94 in Category IV (p = 0.79). In women, the odds ratio (OR) rose gradually up to 1.78 (p < 0.025) in Category III, only to decline in Category IV. The OR in men was slightly, insignificantly, and equally elevated in Categories III and IV. Patients with CHD in Category III were not distinguished from those in Category IV by the studied risk parameters. It was suggested that high risk for CHD—particularly in subjects with slightly elevated or normal cholesterol levels—is often not reflected by extreme increases of fasting triglycerides but best by modest elevations (140–212 mg/dl), which serve better as a marker of triglyceride‐rich lipoprotein particles. This knowledge may prove to be of value in population screening and individual risk assessment.