bluuebunny/crossref_metadata_2025_split huggingface dataset:
Diastolic heart function—pathophysiology, characterization, and therapeutic approaches
Authors: Modersohn Diethelm , Walde Torsten , Bruch Leonhard 
Published: February 2009

AbstractIn recent years diastolic cardiac function has attracted increasing attention since parameters of diastolic function were found to be altered earlier or more specifically than parameters of systolic function. Diastolic cardiac function is determined by both active (muscular relaxation, redistribution of calcium, synchronization, etc.) and passive (myocardial structure, fibrosis, etc.) factors. As a consequence, a comprehensive assessment of diastolic cardiac function cannot be based on one single parameter. For a complete analysis of diastolic function it is necessary to perform invasive diagnostic procedures involving the measurement of atrial and ventricular pressures, as well as the registration of volume changes with a high time resolution. In addition, it is necessary to measure wall thickness and ventricular configuration, so that apart from filling parameters the stress‐strain relationship can be obtained. Noninvasive techniques (Doppler echocardiography, radionuclear ventriculography, apexcardiography) may suggest alterations in diastolic function as well. They ought to be complemented by additional diagnostic procedures (pulmonary pressure, stress testing, etc.). Therapy must consider potentially harmful effects on diastolic function parameters, particularly if changes in myocardial oxygen consumption may result (heart rate, parietal wall stress). Calcium antagonists (verapamil, diltiazem, nifedipine), phosphodiesterase inhibitors (milrinone), beta‐adrenergic agonists and antagonists with vasodilating effects (e. g., celiprolol) all have beneficial effects on diastolic myocardial function.A range of diastolic function parameters is being reviewed in the following paper. Their role in the estimation of cardiac function and their responsiveness to therapy in hypertrophy, cardiomyopathy, and coronary heart disease is being discussed.
A comparison of the effects of adenosine and verapamil on the conduction and pacemaker system of isolated guinea pig hearts
Authors: Stark Gerhard , Stark Ulrike , Bachernegg Maria , Kasper Karin , Kickenweiz Elisabeth , Decrinis Martin 
Published: February 2009

AbstractAdenosine and verapamil are effective in the treatment of supraventricular arrhythmias. Also, both substances can provoke sinus node arrest or a third‐degree atrioventricular (AV) block with a ventricular escape rhythm. The aim of this study was to compare the effects of adenosine and verapamil on sinus rate and on the rate of the ventricular escape rhythm while a third‐degree AV block was induced by both drugs. Experiments were performed on isolated spontaneously beating guinea pig hearts perfused by the method of Langendorff. A third‐degree AV block was induced by adenosine at a concentration of 30 μm and by verapamil at a concentration of 1 m̈m. Adenosine (30μm) reduced sinus rate only moderately whereas it nearly halved the rate of the ventricular escape rhythm compared with that produced by cutting the AV node. In contrast, verapamil left the rate of the ventricular escape rhythm unchanged but nearly halved the spontaneous sinus rate compared with control conditions. In conclusion, adenosine and verapamil given at dosages with comparable effect on the AV node have markedly different effects on different pacemakers in the same heart. In the treatment of supraventricular arrhythmias, adenosine probably should be used with great caution since it can cause a very slow ventricular escape rhythm.
Long‐Term prognosis after myocardial infarction: Univariate and multivariate analysis of clinical characteristics in 1,000 patients
Authors: Kambara Hirofumi , Nakagawa Masao , Kinoshita Masahiko , Kawai Chuichi 
Published: February 2009

AbstractTo examine the clinical outcome for patients with myocardial infarction and to analyze clinical predictors for long‐term prognosis, 1,000 patients were studied retrospectively. Between January 1983 and December 1987, 1,002 consecutive patients with myocardial infarction, who resided in the Kyoto and Shiga districts, were reviewed after coronary arteriography, but in two patients medical records were not located. During 3.3 ±2.0 years, 75 patients died of cardiac causes and 301 experienced cardiac events (death, reinfarction, and revascularization). Overall 5‐year cardiac mortality was 8% and cardiac event rate was 35%. Among determinants of age, smoking, hypertension, diabetes mellitus, heart failure, postinfarction angina, serious arrhythmia, mitral regurgitation, digitalis and diuretics administration, ejection fraction (EF), left main trunk disease, and number of diseased coronary arteries selected by univariate analysis, multivariate analysis revealed that heart failure, EF, number of coronary vessel disease, diabetes, and mitral regurgitation were the important predictors of cardiac death. For cardiac events, multivariate analysis demonstrated that the number of diseased coronaries, postinfarction angina, and left main trunk disease were significant predictors. Therefore, impaired left ventricular function and myocardial ischemia appear to be important markers for cardiac death, but impaired left ventricular function does not appear to be a predictor for cardiac events. The data obtained in this study will be useful in the assessment of patients with myocardial infarction and will be of clinical significance in predicting mortality and cardiac events.
Minimal residual coronary obstructions in patients who suffered a first myocardial infarction. A prospective study comparing coronary angiography and exercise thallium scintigraphy
Authors: Macieira‐Coelho Eduardo , Cantinho Guilhermina , Da Costa Brás B. , Garcia‐Alves Mário , Lacerda António P. , Dionisio Isabel , Carvalho Madalena , De Pádua Fernando 
Published: February 2009

AbstractThe purpose of the present study was to correlate the presence of minimal coronary obstruction (≤ 50%) assessed by coronary angiography with the presence of myocardial scar and ischemia detected by thallium‐201 myocardial perfusion imaging. The study included 83 consecutive patients (74 men and 9 women) with a mean age 55.4±8.5 years who suffered a first myocardial infarction and did not undergo thrombolytic therapy. In all patients, coronary angiography, left ventriculography, and exercise thallium‐201 tomographic scintigraphy were performed within 3 to 5 months of the myocardial infarction. Coronary arteriograms showed minimal residual obstructions in 37 (45%) patients. Of a total of 54 patients with ≤ 50% obstruction, 18 showed persistent defects and 22 reversible defects on thallium scintigrams. The present study showing estimated angiographic stenosis of ≤ 50% as being responsible either for myocardial scar or myocardial ischemia on postexercise thallium scintigrams leads us to conclude that percent value of stenosis does not accurately predict the pathophysiologic significance of coronary atherosclerotic lesions in patients who suffer a myocardial infarction. After a first myocardial infarction, coronary angiographies and thallium‐201 scintigrams are complementary for an optimal treatment strategy for selected subsets of patients.
Atrioventricular nodal reentry tachycardia: Electrophysiologic comparisons in patients with and without 2:1 infra‐his block
Authors: Willems Stephan , Shenasa Mohammad , Borggrefe Martin , Hindricks Gerhard , Chen Xu , Rotman Brigitte , Kottkamp Hans , Haverkamp Wilhelm , Breithardt GÜNter 
Published: February 2009

AbstractPatients with atrioventricular nodal reentry tachycardia (AVNRT) occasionally may demonstrate a 2:1 infra‐His block during tachycardia. However, the electrophysiologic background of this phenomenon has not been established so far. In the present study we compared the electrophysiologic parameters of 10 consecutive patients with a transient 2:1 infra‐His block during AVNRT of the common type (Group A) with those of 17 consecutive patients without this phenomenon during tachycardia (Group B). Transient 2:1 infra‐His block occurred without termination of the tachycardia in all 10 patients of Group A. The tachycardia sustained despite intermittent or permanent conduction disturbance of the infrahisian tissue in 8 of these 10 patients. In comparison, the electrophysiologic parameters of 17 patients without 2:1 block during AVNRT of the common type (Group B) were analyzed. A significantly longer antegrade (318±58 ms vs. 259±50 ms) and retrograde (308±59 ms vs. 239±20 ms) AV conduction capacity could be demonstrated in these patients. The tachycardia cycle length did not differ significantly between the two groups, although the mean tachycardia cycle length was 48 ms longer in patients of Group B. These observations demonstrate an advanced conduction capacity in patients with a transient infra‐His block during AVRNT of the common type. This study underlines that the reentry circuit in AVNRT is not necessarily dependent on infrahisian tissue.
Atrioventricular junctional reentrant tachycardia utilizing multiple retrograde fibers during ablation of the slow pathway
Authors: Katritsis Demosthenes , Slade Alistair , John Camm A. , Rowland Edward 
Published: February 2009

AbstractThis report deals with a patient with atrioventricular (AV) reentrant junctional tachycardia who, during radiofrequency ablation of her slow pathway, developed both anterior and posterior type of slow‐fast atrioventricular nodal reentry; in both tachycardias different fibers were alternately utilized for retrograde conduction, thus resulting in alternating tachycardia cycle lengths. This observation provides further evidence in favor of the multifiber structure of the AV node in patients with AV reentrant junctional tachycardia.
Bundle‐Branch reentry tachycardia
Authors: Kusniec Jairo , Strasberg Boris , Birnbaum Yochai , Sclarovsky Samuel 
Published: February 2009

AbstractA 21‐year‐old man with aborted sudden death developed bundle‐branch reentry tachycardia at electrophysiologic study. Ablation of the right bundle branch was performed in an attempt to eliminate the recurrence of ventricular arrhythmia. The clinical arrhythmia was no longer inducible; however, a second type of ventricular tachycardia of a different mechanism and origin was induced. Following a new clinical episode of ventricular tachycardia with hemodynamic deterioration, an automatic implantable cardioverter and defibrillator was implanted.
Prognosis during one year of follow‐up after acute myocardial infarction with emphasis on morbidity
Authors: Herlitz Johan , Karlson BJörn W. , Sjölin M. , Ekvall Hans‐Eric , Hjalmarson Årke 
Published: February 2009

AbstractPrevious descriptions of the prognosis after acute myocardial infarction (AMI) have mainly included patients admitted to coronary care units, often with an upper age limit. This study describes the prognosis, with emphasis on morbidity, during 1 year in 921 patients admitted to one single hospital with AMI regardless of age and regardless of whether or not they were admitted to the coronary care unit. During the first year, 29% of the patients died and 16% developed a reinfarction. Fifty‐four percent required rehospitalization for various reasons, mainly for AMI, chest pain of other origins, and congestive heart failure. After 1 year, 52% of the surviving patients had symptoms of angina pectoris. Among patients younger than 65 years, only 37% were back to work full time after 1 year. Of patients alive after 1 year, 25% fulfilled the following criteria: no reinfarction, no rehospitalization, and no angina pectoris. Of patients aged less than 65 years at follow‐up, 12% fulfilled the same criteria and were back to work full time after 1 year. in this unselected, consecutive series of patients with AMI, mortality and morbidity were high during the first year. Only a small percentage of patients were free of events or symptoms of angina pectoris.
Influence of glyceryl trinitrate on venous and arterial effects of chronic, asymmetric isosorbide dinitrate treatment in patients with ischemic heart disease
Authors: Jørgensen LARS H. , Refsum Harald E. , Thaulow Erik 
Published: February 2009

AbstractAsymmetric dosage regimes have been introduced to circumvent development of nitrate tolerance. This study assessed invasively the hemodynamics during supine rest and exercise before and after 4 weeks treatment with 30 mg isosorbide dinitrate (ISDN) or placebo asymmetrically b.i.d. in 14 randomized patients with stable ischemic heart disease in a double‐blinded study. An intravenous infusion of glyceryl trinitrate (GTN) was used to assess possible nitrate tolerance. During the initial, medication‐free exercise all patients had increased pulmonary arterial wedge pressure (PAWP) 31.4 ± 5.56 mmHg (mean ± SD), showing impaired left ventricular function, while mean arterial pressures (MAP) rose from 112 ± 16.3 mmHg at rest to 141 ± 15.9 mmHg during exercise. After 4 weeks ISDN treatment, mean exercise PAWP and MAP, 3 h after morning dose, were reduced to 22.4 ± 7.09 mmHg and 127 ± 18.2 mmHg, respectively. Before the ISDN treatment, GTN reduced exercise PAWP to 13.9 ± 5.27 mmHg and MAP to 119 ± 11.2 mmHg, whereas after 4 weeks ISDN treatment, the addition of GTN did not reduce exercise PAWP and MAP to the same low levels. Thus, the applied ISDN regimen improved the hemodynamics, but induced a definite, partial nitrate tolerance.
Decreased adrenergic response in hypertensive patients without left ventricular hypertrophy
Authors: Sugishita Yasuro , Iida Keiji , Fujieda Kazushi , Yukisada Kimihiko 
Published: February 2009

AbstractTo analyze the adrenergic responses and to compare them between hypertensive patients with and without left ventricular hypertrophy (LVH), left ventricular (LV) fractional shortening (FS) and end‐systolic wall stress (ESS) were measured by echocardiography and the inotropic response to the infusion of isoproterenol (0.02 μg/kg/min for 5 min) was studied in 25 hypertensive patients without LVH [H(‐)] and 30 hypertensive patients with LVH [H(+)]. LVH was determined by echocardiography. Age, gender, heart rate, systolic and diastolic blood pressures, LV end‐systolic and end‐diastolic diameters, and FS were matched between the groups. The tests were performed before introduction of antihypertensi ve treatment or 4 weeks after its discontinuation. ESS showed a significant inverse linear relation with FS in all the subjects before isoproterenol infusion. The inotropic response to isoproterenol was measured as the increase of FS corrected for the decrease of ESS (ΔFS/‐ΔESS), that is, the slope of the change of the relation between FS and ESS. The change in ΔFS/‐ΔESS was significantly smaller (0.49 ± 0.15 cm2/g, mean ± SD) in H(−) than in H(+) patients (1.01 ± 0.57 cm2/g) (p < 0.001). It is concluded that, compared with the H(+) group, adrenergic response is depressed in H (−) patients. This depression might be etioloically related to the phenomenon that LVH did not develop in the H(−) group in spite of the same level of pressure load as in the H(+) group.
Pathology of aortic valve stenosis and pure aortic regurgitation a clinical morphologic assessment—part I
Authors: Waller Bruce , Howard Jane , Fess Stephen 
Published: February 2009

AbstractThis two‐part article examines the histologic and morphologic basis for stenotic and purely regurgitant aortic valves. Part I discusses stenotic aortic valves and Part II will discuss causes of purely regurgitant aortic valves. In over 95% of stenotic aortic valves, the etiology is one of three types: congenital (primarily bicuspid), degenerative, or rheumatic. Other rare causes of stenotic aortic valves include active infective endocarditis, homozygous type II hyperlipoproteinemia, and systemic lupus erythematosis. The causes of pure aortic regurgitation are multiple but can be separated into diseases affecting the valve (normal aorta) (infective endocarditis, congenital bicuspid, rheumatic, floppy), diseases affecting the walls of aorta (normal valve) (syphilis, Marfan's, dissection), disease affecting both aorta and valve (abnormal aorta, abnormal valve) (ankylosing spondylitis), and diseases affecting neither aorta nor valve (normal aorta, normal valve) (ventricular septal detect, systemic hypertension). Diseases affecting the aortic valve alone are the most common subgroup of conditions producing pure aortic valve regurgitation.
Coronary artery‐pulmonary artery fistula associated with hypertrophic cardiomyopathy
Authors: Geist Michael , Rozenman Yoseph , Hasin Yonathan , Gotsman Mervyn S. 
Published: February 2009

AbstractThis report describes two patients with the combination of a coronary artery fistula from the left anterior descending artery (LAD) to the pulmonary artery together with hypertrophic cardioinyopathy.
Beta‐adrenergic blockade following thrombolytic therapy: Is it helpful or harmful?
Authors: Becker Richard C. 
Published: February 2009

AbstractBeta‐adrenergic blockade has been a mainstay in the treatment of patients with acute myocardial infarction for nearly two decades. Clearly, it has withstood the test of time. The emergence of thrombolytic therapy, however, has shifted the medical community's focus, raising questions as to the benefit of beta‐adrenergic blockade. Although further investigation is warranted, the available evidence suggests that beta blockers can be given safely to selected patients following coronary thrombolysis, particularly in the absence of moderate to severe left ventricular dysfunction.
Quantification of infarct size by thallium‐201 single‐photon emission computed tomography using the unfolded map method. Comparison with QRS score and angiographic infarct size at 4 weeks after infarction
Authors: Shimada Tomoyoshi , Tsuda Nobuyuki , Kamihata Hiroshi , Suga Yutaka , Kurimoto Tohru , Iwasaka Toshiji , Inada Mltsuo 
Published: February 2009

AbstractA new technique of data processing, the unfolded map method, was used with thallium‐201 single‐photon emission computed tomography to quantify infarct size in 35 patients with single‐vessel disease at 4 weeks after their first myocardial infarction (24 anterior and 11 inferior infarcts), and the results were compared with those obtained by electrocardiography and contrast left ventriculography. The myocardial borders and the infarcted region were defined using the threshold technique and a cutoff value of 55%. Count profile data for each short‐axis slice were unfolded zonally into single planes with the same ratio, and their areas were calculated from the slice thickness and radius. Thus, the size of the unfolded map represented the actual left ventricular myocardial area Infarct size was quantitated from the ratio of pixels in the infarcted region to those in the whole map, and the ratio itself was used as the percent infarct size. Although a defect 1 cm in diameter (0.8 cm2) could not be detected in a phantom study, defects ≥ 2 cm in diameter (≥3.1 cm2) could be measured satisfactorily. The infarct size and percent infarct size determined by the unfolded map method correlated well with the QRS score (r = 0.841 and r = 0.838), the percentage of abnormally contracting segments on left ventriculography (r = 0.835 and r = 0.87 7), and the ejection traction (r = ‐0.835 andr = ‐0.856). These data indicate that the unfolded map method provides adequate quantification of infarct size, even in the chronic phase, without complicated data processing.
Direct recording of sinus node potentials using electrode catheter techniques
Authors: Lévy Samuel , Lekieffre Jean 
Published: February 2009

AbstractDirect recording of sinus node (SN) potentials using electrode catheter techniques is feasible and may be achieved in 50‐86% of patients, ft takes 15‐30 min using commercially available catheters. However, obtaining stable recordings is often difficult, necessitating direct contact of the distal electrode with the endocardial area underlying the sinus node. There is a wide range in sinoatrial (SA) intervals (30‐150 ms) obtained, and an overlap exists between patients with normal and abnormal SN function. Consequently, measurement of the SA interval alone may not be a reliable tool for diagnosing SN dysfunction. However, direct SN recordings have a theoretic value, allowing differentiation of disorders of SA conduction from disorders of the impulse generation.
Unstable angina: Prognosis, noninvasive risk assessment, and strategies for management
Authors: Mcclellan Joseph R. 
Published: February 2009

AbstractRisk stratification in patients with unstable angina is a major clinical problem with important therapeutic implications. Antiplatelet therapy is clearly effective in reducing the occurrence of myocardial infarction and death in this syndrome. Interventions including coronary bypass surgery and coronary angioplasty are frequently recommended for these patients, but the most appropriate application of these techniques needs to be further defined. After a brief discussion of the value of medical and interventional therapies, this review focuses on the clinical and noninvasive predictors of adverse events in unstable angina. An overall management strategy for these patients, based on current information, will be proposed.
Forearm compartment syndrome following thrombolytic therapy for acute myocardial infarction
Authors: Burnside Joyce , Costello John M. , Angelastro Nicholas J. , Blankenship James 
Published: February 2009

AbstractThrombolytic therapy for myocardial infarction may contribute to bleeding complications when central venous or arterial access is required, but peripheral venous access is usually uncomplicated. We report a patient in whom tissue plasminogen activator and subsequent intravenous heparin exacerbated bleeding from a disrupted intravenous access site, leading to acute compartment syndrome requiring surgical decompression. This case emphasizes the risks associated with iatrogenic trauma during thrombolytic therapy.
The use of activated clotting times to monitor heparin therapy during and after interventional procedures
Authors: Bowers John , Ferguson James J. 
Published: February 2009

AbstractUse of the activated clotting time (ACT) was recommended in the mid 1970s to guide administration and reversal of heparin during cardiopulmonary bypass. As the applications of cardiopulmonary bypass spread, so too did the need for more efficient techniques to assess coagulation status. This led to the development of automated ACT measurements. Today, the importance of coagulation and anticoagulation has been further highlighted by recent advances in the field of interventional cardiology. More and more cardiologists are using in‐laboratory bedside coagulation monitoring to assess heparin requirements during interventional procedures such as percutaneous transluminal coronary angioplasty (PTCA). This review focuses on the development of anticoagulation monitoring and provides historic information on the clinical use of heparin. The application of ACTs in the catheterization laboratory and in other clinical situations is discussed, along with alternative methods for bedside assessment of coagulation status. No definite guidelines have been established for ACT monitoring during invasive intravascular procedures; thus its role continues to be refined. in the meantime, the ACT appears to be an extremely useful method for monitoring heparin therapy and the adequacy of anticoagulation.
Intrapulmonary artery coiling of a permanent pacing lead
Authors: Trigano J. A. , Batsou R. , Lauribe P. , Paganelli F. , Gérard R. , Lévy S. 
Published: February 2009

AbstractIntrapulmonary artery displacement of a permanent ventricular lead is reported to be a severe form of lead coiling and is attributed to the failure of the fixation procedure. The lead instability indicated a need for surgical correction.