bluuebunny/crossref_metadata_2025_split huggingface dataset:
Early and late potentials in postinfarction patients
Authors: Walczak F. , Kepski R. , Hoffman M. 
Published: February 2009

AbstractInjury within the myocardium may cause disturbances of the intraventricular conduction and may be manifested by altered spectrum of the QRS complex. The purpose of this report is to indicate the existence of microvolt early waves appearing at the beginning of the QRS complex in some postinfarction patients with low ejection fraction. The method used incorporated the high resolution ECG recording, where the “pyramid” electrode location was applied. Results indicated a relationship between high frequency potentials, QRS duration time, and ejection fraction, as well as dependence between ventricular tachycardia/fibrillation (VT/VF) occurrence and early and/or late ventricular activity. In patients with secondary VT/VF where early and late potentials were found, the ejection fraction (EF) was the lowest (26 ±15%). Early waves appeared more often in patients with secondary VT/VF (30%) compared with those with primary VT/VF (8%). In patients without VT/VF and without myocardial infarction (MI) early potentials were not remarked. In those patients late potentials also appeared less often. It could be concluded that existence of early potentials, late activity, and significant prolonged total ventricular activation time is associated with wide dispersion and nonuniform delay of the electrical activity within the myocardium as well as with serious lowering of the ejection fraction. Therefore, existence of early waves seems to be a significant diagnostic factor for the poor hemodynamic condition as well as a serious warning for the recurrent late ventricular tachycardia/fibrillation.
Influence of atenolol on the relationship between heart rate and qt interval in patients with exercise‐induced myocardial ischemia
Authors: Ferraro Sergio , Maddalena Giovanni , D'Agosto Vicente , D'Alto Michele , Chiariello Massimo , Santomauro Maurizio , Romano Massimo , Fazio Serafino 
Published: February 2009

AbstractThe aim of this study was to analyze the relationship between heart rate and QT interval (HR‐QT) during exercise in control subjects (Group A) and in patients with coronary artery disease (CAD) with effort angina and without previous myocardial infarction (MI) (Group B). The diagnosis of CAD was confirmed by coronarographic examination. The correlation HR‐QT was significant (p <0.001) in both groups on effort and at recovery. The analysis of the regression HR‐QT was carried out separately, both on effort in upright position and at rest in supine position, to avoid the influence of posture on QT length. During effort, the regression line showed lower slope and intercept values in Group B (p<0.001) than those for Group A. A similar behavior was also observed at rest. Thus, at the highest heart rate, where ECG signs of ischemia (ST depression >1 mm) frequently occurred, a longer QT interval was present in Group B. Moreover, in Group B, the QT interval in the presence of ECG signs of ischemia was significantly longer (p<0.01) than in Group A at comparable heart rates both on effort and at rest, thereby confirming the result obtained by comparing both regression lines. The same effort protocol was repeated in Group B patients after acute administration of atenolol 100 mg per os. After atenolol administration, the analysis of the regression HR–QT in Group B clearly showed a shorter QT interval than that obtained in washout period during the baseline test at the highest heart rates where the ECG frequently showed signs of ischemia. This was proven by the presence of a higher slope (p < 0.05) of the regression line HR‐ QT during treatment compared with that obtained in the same group without therapy. In conclusion, transient myocardial ischemia provokes a longer QT interval in patients with CAD in comparison with normal subjects. Atenolol affected the HR–QT relationship showing a shorter QT interval at the highest heart rates, particularly when ECG showed signs of ischemia, compared with that achieved in the same patients in washout.
Evaluation of myocardial perfusion defects by means of “bull's eye” images
Authors: Minoves M. , Garcia A. , Pavia J. , Herranz R. , Setoain J. , Magriña J. 
Published: February 2009

AbstractThe purpose of this study was to evaluate the usefulness of so‐called “bull's eye” imaging as a simplified display of tomographic slices in the detection of coronary artery disease (CAD). A total of 64 patients were studied at stress and at rest, by single photon emission computed tomography (SPECT), either with thallium‐201 (201T1) or with technetium‐99m methoxy‐isobutyl‐isonitril (Tc‐MIBI). The myocardial perfusion defects detected by bull's eye image alone and in combination with visual analysis of tomographic images were evaluated in all cases, taking coronary arteriographic results as a gold standard. The overall sensitivity and specificity for detection of CAD were as follows: bull's eye imaging, 100% and 70.8%; tomographic imaging (SPECT), 90% and 91.6%. The results of bull's eye imaging and SPECT interpreted together were 96.6% and 83.3%. The regional sensitivity and specificity of bull's eye for individual coronary arteries were: right coronary artery (RCA), 100% and 73.7%; left anterior descending (LAD), 100% and 87.2%; left circumflex (LCx), 100% and 97.3%. For SPECT they were: RCA, 93.7% and 89.5%; LAD, 86.6% and 92.3%; LCx, 73.3% and 97.4%. For bull's eye with SPECT they were: RCA, 94.4% and 86.1%; LAD, 87.5% and 92.1%; LCx, 82.3% and 97.2%. We conclude that the bull's eye image display allows an easier and more objective assessment of myocardial perfusion defects and shows higher sensitivity. However, it has a relatively low specificity which can cause an over‐estimation of perfusion defects. Thus, visual analysis of bull's eye imaging is a useful diagnostic tool but must be evaluated in conjunction with tomographic imaging.
Duplex sonographic detection of internal jugular venous thrombosis after removal of central venous catheters
Authors: Karnik Ronald , Valentin Andreas , Winkler Walther‐Benedikt , Donath Peter , Slany Jörg 
Published: February 2009

AbstractVenous thrombosis is a very common complication of central venous catheters inserted via the jugular or subclavian vein. The aim of this prospective study is to test the suitability of duplex sonography in detecting thrombi in the internal jugular vein after catheter removal and to analyze the number and extent of such thrombus formations. The study group comprised 64 consecutive patients with an average age of 59 ± 16 years admitted to an internal intensive care unit. In 54 cases the catheters were removed under sonographic control. In 10 cases duplex sonography was carried out within 24 h after removal of the catheters. The data of 63 patients were evaluated. In 40 patients (63.5%), thrombi of varying extent were present in the jugular vein. No significant correlations were found between thrombus formation and the basic disease, duration of cannulation, the type of catheters used, and the mode of heparinization (therapeutic vs. low‐dose). Local inflammation signs and local hematoma showed a significantly higher incidence (p < 0.01) in patients with thrombus formation. Duplex sonography lends itself as a valuable diagnostic tool in the diagnosis of thrombus formation in the internal jugular vein after removal of central venous catheters. Sonographic examinations should be carried out in all long‐stay patients at an intensive care unit, in whom central venous catheters are inserted repeatedly via the internal jugular vein.
Mitral regurgitation following first‐time acute myocardial infarction— early and late findings by doppler echocardiography
Authors: Alam Mahbubul , Thorstrand Curt , Rosenhamer Gunnar 
Published: February 2009

AbstractA total of 61 patients with first‐time mild to moderate acute myocardial infarction and no reinfarction within the following 2 months were studied prospectively by Doppler echocardiography before hospital discharge and after 2 months to evaluate the prevalence of mitral regurgitation. Twenty‐one age‐matched healthy subjects served as controls. At baseline, the prevalence of Doppler‐recorded mitral regurgitation was 74% and 29% in patients and controls, respectively. In the patients, the regurgitant flow measured by color flow Doppler was 1.04 cm2 (range 0.2–8 cm2) and occupied 7.5% (range 2–45%) of the left atrial area. Corresponding figures for controls were 0.35 cm2 (0.1–0.6) and 2.4% (0.7–4.5), respectively. On continuous wave Doppler, most patients (33/45) had Doppler signals similar to those of healthy controls. The prevalence of mitral regurgitation was about the same in anterior and inferior infarction (75 and 72% respectively). In the patients, the prevalence was similar after 2 months (79%) with minor changes in the Doppler characteristics of the regurgitation (regurgitant flow 1.12 cm2 and occupying 8.1% of left atrial area). The study demonstrates that in a group of patients with first‐time mild to moderate myocardial infarction the prevalence of Doppler‐recorded mitral regurgitation is high and mild in severity in the majority of the cases. The changes remain almost similar even after 2 months.
Abnormal qt intervals associated with negative t waves induced by antiarrhythmic drugs are rapidly reduced using magnesium sulfate as an antidote
Authors: Gurfinkel Enrique , Mautner Branco , Pazos Angel Alvarez 
Published: February 2009

AbstractThis study was undertaken to determine whether prolonged QTc interval as a consequence of abnormal repolarization induced by coronary disease or antiarrhythmic drugs could be shortened by intravenous administration of magnesium sulfate. A total of 21 patients with basal prolonged QTc intervals (QTc > 500 ms) were divided in two groups: 7 with ischemic coronary disease and negative T waves (Group A), and 14 treated with antiarrhythmic drugs (Group B). Nine of the latter had negative T waves (Subgroup B‐1) and five had positive T waves (Subgroup B‐2) recorded in precordial leads. Nine patients were taking amiodarone and six quinidine. Magnesium sulfate was given intravenously in a bolus of 3.75 g (25% solution) over 3 min. Patients had normal electrolyte serum levels. The prolonged QTc and JTc intervals were shortened after magnesium sulfate in patients of Subgroup B‐1 from the basal values [QTc 20.7% and JTc 25.4%, (p = < 0.0001 and 0.02, respectively)]. None of the patients in Group A or Subgroup B‐2 experienced altered QTc or JTc intervals. While some antiarrhythmic drugs are capable of altering the refractoriness of ventricular cells, probably by causing changes in the intracellular metabolic pathways, in patients with coronary disease gaps in the membrane induced by ischemic injury let calcium enter the cells parallel with dispersion of ventricular repolarization. When secondary negative T waves are present, magnesium sulfate as an antidote probably acts as a blocking agent at the sarcoplasmic reticulum, thus reducing both QTc and JTc intervals.
Acute myocardial infarction with papillary muscle rupture
Authors: Hackel Donald B. , Wagner Galen S. 
Published: February 2009

AbstractThe subject of this report is a 57‐year‐old obese, hypertensive woman who had been well until the onset of severe chest pain and hypotension. She had to be defibrillated four times on her way to the hospital. The diagnosis of acute inferior‐posterior infarction was made by electrocardiogram (ECG) and there was a markedly elevated serum creatine kinase (CK) (including the MB fraction). The patient had a very low cardiac output and ejection fraction. A lung scan revealed possible pulmonary embolism for which she was anticoagulated. She remained hypotensive and hypoxemic and, on Day 17 of her hospital stay, she had a bout of severe dyspnea. A new systolic murmur was heard and the clinical diagnosis of ruptured papillary muscle was made and confirmed by echocardiography, and later at autopsy. All three coronary arteries were severely atherosclerotic and, in addition, the right coronary artery was completely closed by a thrombus. This case clearly illustrates the major pathological changes in the heart that correlate with the clinical findings in patients with a myocardial infarct that is complicated by left ventricular papillary muscle rupture. The pathophysiological effects of this condition, as illustrated in this case report, include the following:1. The posterior papillary muscle was almost completely separated from its base, with only a thin strip of muscle intact. The mitral valve thus was insufficient (a “flail valve“); this markedly reduced the ejection fraction of the left ventricle, increased its end‐diastolic volume and pressure, produced a damming of blood in the pulmonary circulation, and this resulted in the pulmonary edema seen on the chest x‐ray.2. Cardiac hypertrophy (weight = 561 g) was undoubtedly the result of the increased workload imposed on the left ventricle by the systemic arterial hypertension that this patient had for several years. A high blood pressure that persists after a myocardial infarct predisposes to myocardial rupture, but was probably not a risk factor in her case since it did not persist.3. The cause of the myocardial infarct was the thrombotic occlusion of the right coronary artery (on top of severe three‐vessel coronary atherosclerosis), which resulted in infarction of the right as well as the posterior left ventricle and can partly explain the mistaken clinical impression that she had pulmonary emboli.
Infective endocarditis due to fusobacterium nucleatum: Case report and review of the literature
Authors: Shammas Nicolas W. , Murphy Gerald W. , Eichelberger James , Klee Daniel , Schwartz Ronald , Bachman William 
Published: February 2009

AbstractEndocarditis caused by Fusobacterium nucleatum is exceedingly rare. We report a case of F. nucleatum right‐sided endocarditis in a patient with no known intravenous drug abuse. A detailed computer and manual search of the literature using Med‐Line and Index Medicus, respectively, revealed a total of five cases of endocarditis due to this species. The clinical characteristics and the patient's hospital course are summarized and reviewed.
The puzzle of normal coronary arteries in the patient with chest pain: What to do?
Authors: E. Assey Michael 
Published: February 2009

AbstractOver one million Americans undergo cardiac catheterization each year because of chest pain, with the expectation that coronary artery disease will be found. However, up to 30%—a subgroup that includes patients with both cardiac and noncardiac pathology—will have angiographically normal coronary arteries. While the prognosis of the group as a whole is excellent, successful management requires a clear understanding of the multiple and varied conditions that can cause this syndrome.
Noninvasive detection of coronary artery disease by assessing diastolic abnormalities during low isometric exercise
Authors: Manolas Jan 
Published: February 2009

AbstractThe handgrip‐apexcardiographic test (HAT) is a simple low‐level (40% of maximal voluntary handgrip during 2 min) stress test which can detect left ventricular (LV) diastolic abnormalities. To determine whether it contributes to the diagnosis of coronary artery disease (CAD), HAT was obtained in 68 patients–47 with and 21 without angina pectoris–who prospectively underwent coronary arteriography. According to the highest or lowest individual values of diastolic apexcardiographic indices in 255 healthy volunteers, a pathologic or positive HAT was defined by the presence of at least one of the following new criteria: (1) A wave relative to total height of apexcardiogram during and/or after handgrip>21%, (2) total apexcardiographic relaxation time (TART) during handgrip>TART at rest > 143 ms and/or TART corrected for the duration of diastole (TARTT) during handgrip <0.14, or (3) diastolic amplitude time index (DATI), given by dividing TAR‐TI and A wave relative to total diastolic amplitude of apex tracing during handgrip<0.27. HAT was positive in 20 of 21 patients with single‐vessel disease (sensitivity 95%), 21 of 24 patients with double‐vessel disease (sensitivity 88%), and in 22 of 23 patients with triple‐vessel disease (sensitivity 96%). Furthermore, HAT was positive in 20 of 21 (95%) patients without symptoms. Thus, the overall sensitivity of HAT for detecting CAD was 93%. This study is the first to demonstrate the high sensitivity of HAT in identifying patients with CAD with or without symptoms by assessing diastolic apexcardiographic abnormalities during low‐level isometric stress. Thus, HAT potentially could become an additional simple diagnostic tool for noninvasive detection of patients with CAD.
Anatomy, histology, and pathology of the cardiac conduction system: Part I
Authors: F. Waller Bruce , E. Gering Lawrence , D. Slack John , A. Branyas Nancy 
Published: February 2009

AbstractNormal anatomic and histologic features of the sinus node, atrial myocardium, and interatrial conduction of the cardiac impulse are reviewed. The controversy surrounding atrial conduction via specialized atrial cells versus specific in‐ternodal tracts (between sinus and atrioventricular nodes) is discussed.
Percutaneous mitral balloon valvotomy in a patient with coexistent mitral stenosis and hypertrophic cardiomyopathy
Authors: Chow Wing‐Hing , Chow Tsun‐Cheung , Wat Ming‐Sun , Cheung King‐Loong 
Published: February 2009

AbstractA patient with coexistent mitral stenosis and hypertrophic cardiomyopathy is described, in whom symptoms related to impaired left ventricular diastolic filling improved after successful percutaneous mitral balloon valvotomy.
A simultaneous study of doppler‐echo and catheterization in noninvasive assessment of the left ventricular dp/dt
Authors: Ge Zhiming , Duran Carlos , Zhang Yun , Kang Weigiang , Fan Dongsheng 
Published: February 2009

AbstractTo confirm the feasibility and accuracy of the method for the noninvasive measurement of the left ventricular dp/dt, 53 patients with mitral regurgitation underwent simultaneous determination of left ventricular dp/dt by continuous‐wave Doppler echocardiography and cardiac catheterization. Doppler‐determined left ventricular dp/dt is derived from the Doppler mitral regurgitant spectrum by dividing the magnitude of the left ventricular‐atrial pressure gradient rise between 1 and 3 m/s of the mitral regurgitant velocity signal by the time taken for this change. Left ventricular dp/dt by Doppler ranged from 629 to 3494 mmHg/s (x̄ ± SD, 1971 ± 785 mmHg/s), and that by catheterization varied between 716 and 3650 mmHg/s (x̄ ± SD, 1974 ± 727 mmHg/s). There was a high correlation (r = 0.93, y = 0.862 × + 274.77, SEE = 271 mmHg/s, p < 0.001) of left ventricular dp/dt between the two techniques. It is concluded that left ventricular dp/dt is one of the most commonly used parameters for the evaluation of left ventricular systolic function and that Doppler echocardiography provides a new, accurate and noninvasive method of evaluation.
Stent wire cutting during coronary directional atherectomy
Authors: Meyer T. , Schmidt T. , Buchwald A. , Wiegand V. 
Published: February 2009

AbstractDirectional atherectomy represents one potential approach for the treatment of restenosis in stented coronary arteries. In this case report we demonstrate an important pitfall of this angioplasty technique for stent restenosis—inadvertent entanglement of the stent wire in the device. While cutting and removal of part of the wire was achieved in the case presented, this potential adverse event limits the applicability of directional atherectomy for restenosis in coronary stents.
Low‐dose dobutamine stress test for the evaluation of cardiac function using ultrafast computed tomography
Authors: Yamaoka Osamu , Fujioka Hideyuki , Haque Tuhn , Nakamura Yasuyuki , Mitsunami Kenichi , Kinoshita Masahiko , Morita Rikushi , Murata Kiyoshi 
Published: February 2009

AbstractHigh dose‐dobutamine (DOB) has been previously used as a pharmacological stress test to evaluate wall motion abnormalities. As a result, recent stress echocardiography with low‐dose DOB has been reported to be valuable for investigating stunned myocardium after thrombolysis. However, echocardiography requires an operator's skill and experience to evaluate wall motion abnormalities which are subjectively determined by the observer. In contrast, ultrafast computed tomography (UFCT) does not necessarily require extreme technical skill and experience. To evaluate the feasibility of stress UFCT with low‐dose DOB, we scanned 10 normal subjects along the short‐axis by 8‐slice‐multicine mode. After scanning at rest for baseline, we scanned during the administration of 4 and 8 m̈g/kg/min of DOB, respectively, for 5 min. Ejection fraction, contraction, and thickening were higher during 8 m̈g/kg/min of DOB than during 4 m̈g/kg/min of DOB and baseline, while the above values were higher during 4 m̈g/kg/min of DOB than during baseline (p < 0.01). It was possible to detect changes of cardiac function and wall motion due to low‐dose DOB by UFCT. We therefore conclude that UFCT is a reliable modality for evaluating cardiac function and wall motion for low‐dose DOB stress test because of its excellent spatial and contrast resolution.
Exertional hemodynamics in women with chest pain—an aortic doppler ultrasound study–B. Janerot Sjoberg et al.: Women during exercise
Authors: Sjoberg Birgitta Janerot , Wranne Bengt , Swahn Eva 
Published: February 2009

AbstractAortic ultrasound Doppler recordings of stroke volume, maxima] flow velocity, and acceleration can be used to assess central hemodynamic effects of exercise in coronary artery disease (CAD) and left ventricular dysfunction. We wanted to evaluate the time course and amplitude of changes in aortic Doppler ultrasound parameters in women during supine exercise and the potential diagnostic value of a submaximal supine exercise test. For this purpose, 18 women who had undergone coronary angiography because of incapacitating chest pain (10 with significant coronary stenoses and previous myocardial infarction, 8 without stenoses or infarction) were compared with 10 healthy controls. Pathological electrocardiographic (ECG) ST‐segment depression during supine exercise was common in all groups. In the control group, a significant increase of stroke volume (10%), maximal aortic flow velocity (27%), and acceleration (43%) occurred at low load during exercise. Women with CAD showed no increase and a lower cardiac output during exercise, indicating left ventricular dysfunction. Women with syndrome X resembled the controls but had a higher maximal flow velocity at rest, which may indicate hyperdynamic circulation. We conclude that a test up to 40% of seated maximal load is valuable and often sufficient when assessing the hemodynamic effects of supine exercise by Doppler ultrasound in terms of stroke volume, maximal flow velocity, and acceleration. By characterizing left ventricular function in groups of female patients where false‐positive stress ECG reactions are common, Doppler ultrasound may contribute to the understanding and clinical management of women with chest pain.