bluuebunny/crossref_metadata_2025_split huggingface dataset:
Prediction of in‐hospital cardiac events using dipyridamole‐thallium scintigraphy performed very early after acute myocardial infarction
Authors: Bosch Xavier , Magriñá Jordi , March Remei , Sanz GinéS , García Alicia , Betriu Amadeo , Navarro‐López Francisco 
Published: February 2009

AbstractBackground and Hypothesis: Ischemic complications occur frequently during hospitalization after acute myocardial infarction. Dipyridamole‐thallium scintigraphy performed early after admission can detect residual ischemia, may have additional prognostic value and be useful in the management of these patients.Methods: Dipyridamole infusion and 201thallium imaging were performed on the third day of infarction in 114 consecutive patients. Coronary angiography was performed before hospital discharge in 90% of patients and exercise testing was performed at the time of discharge in patients without contraindications.Results: Side effects occurred in 28 patients, but they were mild and transient or rapidly reversed with intravenous aminophylline. During hospitalization, three patients died and four had a nonfatal reinfarction. Patients with these major cardiac events had previously shown a higher prevalence of reversible perfusion defects during testing (71 vs. 31 %, p < 0.05). In addition, 19 patients had early recurrent ischemia requiring early in‐hospital revascularization. Overall, cardiac events defined as death, reinfarction, or early myocardial revascularization occurred in 22 patients. Of the patients with these events, 68% had thallium redistribution on initial myocardial scanning compared with 25% of patients without events (p = 0.0001). Patients with cardiac events also showed a higher number of myocardial segments with reversible perfusion defects (1.8 ± 2.2 vs. 0.6 ± 1.3, p = 0.001). Logistic regression analysis revealed that among all the other clinical, scintigraphic, and an‐giographic variables, the presence of thallium redistribution on the dipyridamole‐thallium scan was the only independent predictor of cardiac events, increasing the risk by sixfold. Furthermore, during a 1‐year follow‐up, 14 other patients had ischemic events. Of these, 64% had previously shown thallium redistribution during early dipyridamole testing compared with 19% of patients without cardiac events (p < 0.001).Conclusions: Intravenous dipyridamole‐thallium‐scintigraphy performed very early after myocardial infarction is safe and useful to predict in‐hospital ischemic events.
Assessment of posterior aortic wall motion using echocardiogram in patients with atrial fibrillation
Authors: Nobuoka Sachihiko , Hatano Seiji , Yoshida Akihiro , Nagashima Junzo , Noda Kiyohito , Takada Hideomi , Miyake Fumihiko , Murayama Masahiro 
Published: February 2009

AbstractBackground and hypothesis: Noninvasive evaluation of left ventricular (LV) diastolic function was performed on 12 patients with atrial fibrillation (AF) using posterior aortic wall echocardiogram and a parameter for determining the optimal heart rate in patients with chronic atrial fibrillation was considered.Methods: Subjects were divided into two groups; one with no underlying cardiac disease (AF only group; n = 7) and the other with dilated cardiomyopathy (DCM group; n = 5). Left atrial emptying index (LAEI) obtained from the posterior aortic wall echocardiogram was used as the parameter of LV diastolic function, and R‐R interval‐LAEI relation and minimum R‐R interval showing LAEI = 1.0 were investigated and compared between the two groups.Results: There was a good correlation between R‐R interval and LAEI until LAEI of 1.0 was obtained in all patients. Slope of the regression line was significantly steeper in the AF only group than in the DCM group, and minimum R‐R interval showing LAEI = 1.0 was significantly shorter in the AF only group.Conclusion: Assessment of R‐R interval‐LAEI relation was useful for the noninvasive evaluation of LV diastolic function, and this parameter could be used for clinical application to determine the optimal heart rate in atrial fibrillation.
Left ventricular outflow tract obstruction as a cause for hypotension and symptoms during dobutamine stress echocardiography
Authors: Sorrentino Matthew J. , Marcus Richard H. , Lang Roberto M. 
Published: February 2009

AbstractBackground: Hypotension has been found to occur in more than one‐third of patients during DBSE. Unlike traditional treadmill exercise stress testing, hypotension does not appear to be associated with significant coronary artery disease or left ventricular (LV) dysfunction. Several ischemic and nonis‐chemic mechanisms such as dynamic LV intracavitary obstruction have been implicated in the pathogenesis of hypotension and the induction of symptoms during DBSE.Hypothesis: The purpose of this study was the prospective evaluation of patients referred for dobutamine stress echocardiography (DBSE) to determine (1) the frequency of hypotension during DBSE, (2) the underlying mechanisms responsible for the induction of hypotension, and (3) to describe the cardiac chamber sizes and mass of patients in whom hypotension occurs.Methods: Seventy‐eight consecutive patients were studied during DBSE. Pulsed and continuous‐wave Doppler echocardiography were performed at baseline and at each dobutamine infusion stage. Maximum velocities were recorded. Cardiac output was determined noninvasively at each stage in patients who developed an outflow tract gradient. Echocardiography was used to characterize LV dimensions and mass.Results: During dobutamine infusion, 14 of 78 (18%) patients developed a left ventricular outflow tract (LVOT) velocity ≥ 2.5 m/s. Pulsed Doppler echocardiography verified that the maximal velocity originated in the LVOT. Of the patients who developed an LVOT gradient, 57% had a concomitant hypotensive response to dobutamine compared with 33% of patients without a gradient (not significant). Four of nine patients had a simultaneous fall in cardiac output. Patients who developed an LVOT gradient had smaller LV dimensions and increased wall thicknesses compared with those who did not develop a gradient.Conclusions: Dobutamine stress echocardiography precipitates LVOT obstruction in certain patients. The development of a gradient corresponded with a fall in blood pressure and a decline in cardiac output in nearly half of the patients. These findings suggest that stress‐induced LVOT obstruction may be responsible in part for the hemodynamic changes and symptoms experienced by these patients during exercise.
Cost‐effective management of heart failure
Authors: Parmley William W. 
Published: February 2009

AbstractHeart failure affects more than 2 million Americans, and about 400,000 new cases are diagnosed each year. The direct economic cost is over $10 billion/year. About 75% of this cost is spent on hospitalization, and almost 20% on nursing home care. Drugs such as angiotensin‐converting enzyme (ACE) inhibitors reduce mortality and hospitalization and are thus very cost effective in the management of heart failure. Cost‐effective strategies should focus on keeping patients out of the hospital. Additional savings can be obtained by more appropriate utilization of tests.
Clinical evaluation of algorithms for st measurement during exercise test
Authors: Petrucci Ettore , Balian Vruyr , Ghiringhelli Sergio , Mainardi Luca T. , Bertinelli Maurizio 
Published: February 2009

AbstractHypothesis:Computer processing of the exercise electrocardiogram (ECG) has many advantages, but the reliability of the analysis algorithms is not easily evaluable. No standard annotated database, nor recommended practice for testing and reporting performance results is available: thus, performance evaluation of such devices can be accomplished only by using a set of unannotated recordings, obtained in clinical practice. We evaluated the accuracy of an original microcomputer‐based exercise test analyzer comparing the ST computer output with the measurements obtained by two experienced cardiologists.Methods:Six hundred ECG strips were randomly selected from the exercise test recordings of 60 patients. The ST shift (at J + 80 ms) was blindly assessed by two observers (with the aid of a calibrated lens) and compared with computer measurements. Correlation coefficients, linear regression equations, percent of discrepant measurements, and 95% confidence limits of the mean error were calculated for all leads, peripheral leads, precordial leads, and “stress‐test” leads (II, III, aVF, V4, V5, V6).Results:The computer did not analyze five samples on a total of 600 (0.83%) ECG strips because of excessive noise or signal loss, while 51 (8.5%) were considered unreadable by both observers and 67 (11.2%) were rejected by at least one observer. Correlation between the measurements taken by computer and observer(s) measurements was statistically significant (p < 0.001 for all lead groups), no systematic measurement bias was found, and the mean difference was lower than human eye resolution.Conclusions:Our algorithms provide results as good as those provided by trained cardiologists in measuring ST changes occurring during exercise test. However, this study did not evaluate whether computer improvement of the signal‐to‐noise ratio would allow accurate measurements even on cardiologists' uninterpretable ECG. This potential advantage of computer‐assisted analysis could be assessed only by using a dedicated exercise test database, in which different patterns of noise are superimposed on noise‐free recordings previously annotated for ST level.
Silent ischemic cardiomyopathy and left coronary ostial stenosis secondary to radiation therapy
Authors: Aronow Herbert , Kim Michael , Rubenfire Melvyn 
Published: February 2009

AbstractA 55‐year‐old woman presented with profound congestive heart failure 23 years following mediastinal radiation. Ejection fraction (EF) was 35%. Symptoms markedly improved and EF increased to > 55% following saphenous vein bypass for > 80% ostial left main stenosis. Radiation therapy, a known risk factor for coronary atherosclerosis, may present with reversible severe silent ischemia.
Complete atrioventricular block due to large cell lymphoma: Resolution with chemotherapy
Authors: Guidici Michael C. , Sadler Richard L. , Robken Jon A. , Ahearn Michael A. , Sekharan Raj , Kovach George 
Published: February 2009

AbstractMalignant lymphoma commonly involves the heart. Previous studies have found cardiac metastases in up to 20% of patients dying with lymphoma. Cardiac signs and symptoms of lymphoma are relatively rare, however, and in most cases, the diagnosis is made either postmortem or too late to affect the clinical course. This report presents the first case of complete heart block due to lymphoma that responded to surgery and chemotherapy with return of normal atrial ventricular conduction.
Restenosis—an open file
Authors: Gottsauner‐Wolf Michael , Moliterno David J. , Michael Lincoff A. , Topol Eric J. 
Published: February 2009

AbstractThe main procedural drawback to percutaneous coronary angioplasty is restenosis of the treated site within 6 months. Despite advances in equipment, technique, and adjunctive therapies, restenosis has occurred in approximately one‐third to one‐half of all patients. The biology of restenosis can be divided into plaque persistence and recoil, thrombus formation and transformation, and cellular proliferation and vascular remodeling. Animal models of restenosis have helped to elucidate these mechanisms of restenosis and provide a means to test pharmacologic and mechanical strategies to reduce stenosis recurrence. While numerous agents have been tested in animal models, until recently none has translated into benefit in large‐scale clinical trials. Two therapeutic “hopefuls” which have recently emerged in clinical practice are the potent platelet inhibitors, glycoprotein IIb/IIIa receptor antagonists, and intracoronary metallic stents. The IIb/IIIa receptor antagonists target thrombus formation at the angioplasty site, thereby minimizing abrupt vessel closure acutely and neointimal growth chronically, while intracoronary stents safely produce a large coronary arterial lumen acutely and prevent vessel recoil. Separately, these therapeutic strategies have been shown to reduce clinical restenosis 20‐30% at 6‐month follow‐up. With these encouraging results, the future will certainly provide more pharmacologic and mechanical therapies targeting restenosis. With increased understanding of the restenotic process and continued refinement of effective treatments, it may be possible one day to prevent stenosis recurrence.
Clinical importance of viability assessment in chronic ischemic heart failure
Authors: Calhoun W. B. , Mills Roger M. , Drane Walter E. 
Published: February 2009

AbstractBackground and hypothesis: Revascularization has provided an effective treatment of depressed left ventricular function in patients with chronically ischemic or “viable” myocardium. Assessment of viable myocardium can be achieved by several noninvasive techniques including dobutamine stress echo or radionuclides such as flurodeoxyglucose (F18DG). F18DG uptake studies are based on the assumption that enhanced glucose uptake in areas of diminished blood flow provides evidence of viable myocardium. To determine the clinical utility of viability assessment in the management of chronic ischemic left ventricular dysfunction, we reviewed the findings and short‐term treatment of a series of patients referred for heart failure evaluation who had subsequent F18DG uptake scans.Methods: We retrospectively reviewed 59 consecutive F18DG viability studies in a series of patients who had documented coronary artery disease and depressed left ventricular function. Single photon emission computerized tomography (SPECT) with F18DG was performed in the patients and these images were compared to SPECT images of resting myocardial perfusion using thallium, sestamibi, or teboroxime. Clinical decisions based on the results of these scans were obtained from chart review. Thirty‐day mortality was determined from chart review or contact with the patient's physician. The patients were divided into those without and with F18DG uptake consistent with viable ischemic myocardium. Further analysis included subgroups of patients who were advised to undergo transplantation, revascularization, or to continue medical therapy.Results: Of 34 patients referred for cardiac transplantation, 18 had viable myocardium and 13 underwent revascularization. In the entire study group, 34 of 59 (58%) had evidence of viable myocardium and 29 had subsequent revascularization procedures. Thirty‐day survival for all revascularization patients was 86%.Conclusion: Assessment of myocardial viability with F18DG SPECT imaging in patients with ischemic left ventricular dysfunction led to a clinical decision for revascularization in approximately half the patients with severe coronary disease and left ventricular dysfunction who were evaluated for myocardial viability in our institution.
Relationship between regional abnormality of left ventricular rapid filling and coronary microcirculation disturbance in hypertrophic cardiomyopathy
Authors: Kakoi Hideo , Inoue Teruo , Morooka Shigenori , Hayashi Terumi , Takabatake Yutaka 
Published: February 2009

AbstractBackground and hypothesis: To investigate the mechanism of regional left ventricular diastolic filling disturbance in hypertrophic cardiomyopathy (HCM), we assessed the relationship between abnormalities of regional ventricular rapid filling and regional coronary microcirculation using radionuclide ventriculography and exercise 201thallium (201Tl) myocardial scintigraphy with sector analysis.Methods: Thirty patients with HCM and 14 patients with atypical chest pain syndrome (controls) were studied. Left ventricular images (left anterior oblique view) were obtained by electrocardiogram‐gated 99mtechnetium radionuclide an‐giography and were divided into three sectors radiating from the geometric center. The time‐activity curves and their first derivative curves were analyzed, and the peak filling rate (PFR), the ratio of the time‐to‐peak filling rate per diastolic interval (TPFR/T) were calculated for the global left ventricle and for the lateral and septal sectors. Exercise stress 201Tl myocardial scintigraphy was also performed, and early and delayed images were obtained. The regional washout rate (WR) was then evaluated for the lateral and septal sectors.Results: In HCM patients, the regional PFR in the septal sector (corresponding to the region of hypertrophic myocardium) was 285 ± 76%/s, and was significantly lower than that in the controls (398 ± 90%/s, p <0.01). The regional TPFR/T in the septal sector (32 ± 10%) was prolonged compared with the value of 21 ± 5% in the controls (p <0.05). The regional WR in the septal sector was 21 ± 9%, and was significantly lower than that in the controls (43 ± 5%, p <0.01). Moreover, regional WR correlated positively with regional PFR (r = 0.5, p < 0.05) and showed a weak negative relationship with regional TPFR/T (r = ‐0.4, p <0.07) in the septal sector.Conclusions: These results suggest that regional impairment of rapid filling might be related to a disturbance of the coronary microcirculation in HCM.
Acute hemodynamic deterioration during rapid atrial pacing in patients with hypertrophic cardiomyopathy
Authors: Nakatani Makoto , Yokota Yosiyuki , Yokoyama Mitsuhiro 
Published: February 2009

AbstractBackground and hypothesis: Supraventricular tachycardia and ventricular tachycardia are often observed in patients with hypertrophic cardiomyopathy (HCM) and they often alter the clinical features of HCM. We examine the influence of supra‐ventricular tachycardia on cardiac function and assess the clinical characteristics of patients with HCM.Methods: We studied 32 patients with HCM and 8 normal volunteers using echocardiography under transesophageal rapid atrial pacing.Results: Presyncope‐associated hypotension was observed during rapid atrial pacing in 8 HCM patients, but in none of the normal controls. During rapid atrial pacing (144 ± 8 beats/min in HCM, 146 ± 5 beats/min in controls), systolic blood pressure (SBP), the product of left ventricular filling volume (FV) and heart rate, and fractional shortening (%FS) in the HCM patients decreased significantly compared with the basal values (138 ± 19 mmHg vs. 99 ± 24 mmHg, 5.0 ± 1.21/min vs. 2.9 ± 0.91/min, 41.7 ± 6.2 % vs. 35.2 ± 6.0%, respectively), but these decreases were not observed in normal controls. The decrement of SBP during rapid atrial pacing in HCM patients with a history of syncope was more marked than that in those without such history. The decrement correlated positively with the indices of left ventricular hypertrophy (maximal wall thickness and wall thickness index) and with %FS, and correlated negatively with the endsystolic left ventricular diameter at rest.Conclusions: In some patients with HCM, supraventricular tachycardia causes marked hemodynamic deterioration that may be related to a history of syncope, marked hypertrophy, hyperkinesis, small cavity size, and small filling volume of the left ventricle.
Time to dp/dtmax, a useful index for evaluation of contractility in the catheterization laboratory
Authors: Adler David , Scott Monrad E. , Sonnenblick Edmund H. , Hess Otto M. , Krayenbuehl Hans P. 
Published: February 2009

AbstractHypothesis: The time from onset of contraction to dP/dtmax, td, is suggested as an index of contractility in the catheterization laboratory.Methods: We studied 22 normal patients and 18 patients with myocardial failure in the catheterization laboratory. The two groups were completely separated on the td‐heart rate (HR) plane. In the normal patients, HR = 73 ± 19 beats/min, td= 73 ± 11 ms, and an inverse linear relation td = 109‐0.49 × HR (p<0.001) exist. In the patients with myocardial failure, despite significantly higher HR than in normal patients (HR = 93 ± 14 beats/min) (p <0.001), td paradoxically increased (td = 89 ±11 ms, p<0.0001).Conclusions: These findings support a mathematical analysis of the left ventricular pressure (LVP) during isovolumic contraction in the time domain which shows that td and (dP/dt)/P reflect the time‐dependent aspects of contraction and, hence, decrease with increasing contractility. This study shows that td, at any given HR, is a reliable index of contractility. Thus, a ready‐to‐use td‐HR plot containing a well‐based separation line can provide a reliable and simple method for determining contractility in the catheterization laboratory by examining whether a patient's td value at any HR is below (normal) or above (impaired contractility) the separation line.
Chronotropic incompetence—part i: Normal regulation of the heart rate
Authors: John Camm A. , Fei L. 
Published: February 2009

AbstractKnowledge of normal adjustment of heart rate and its response to exercise is essential for understanding and management of chronotropic incompetence. The autonomic nervous system plays an important role in the modulation of normal heart rate. Chronotropic responses of a normal heart to exercise are associated with parallel hemodynamic changes in order to meet the metabolic demand of the body. Determination of chronotropic incompetence is widely based on the assessment of maximal heart rate. However, maximal effort should always be confirmed before an attempt to measure a maximal heart rate is made.
Hemopericardium with cardiac tamponade after intravenous thrombolysis for acute myocardial infarction
Authors: Mohammad Saeed , Austin Stephen M. 
Published: February 2009

AbstractThis report presents 2 patients with hemopericardium and tamponade encountered among a group of 26 patients who had received intravenous thrombolytic therapy for acute myocardial infarction during an 8‐month time span. Both responded promptly to pericardiocentesis and pericar‐dial catheter drainage. It is suggested that this rarely reported complication has the potential of occurring more frequently with increasing use of thrombolytics followed by aggressive anticoagulant regimens.
Management of intracoronary thrombosis complicating percutaneous transluminal coronary angioplasty
Authors: Boston David R. , Barry William H. , Malouf Assaad 
Published: February 2009

AbstractWith technological advances in equipment and increased experience of operators, the success rates of percutaneous transluminal coronary angioplasty (PTCA) now exceed 90%. However, acute periprocural occlusion continues to complicate approximately 6% of all procedures, and many of these occlusions are due to intracoronary (IC) thrombus. Patients at highest risk for this complication include those with acute ischemic syndromes or with angiographically apparent thrombus. These individuals may be candidates for the use of prolonged heparin infusions prior to dilatation, intracoronary thrombolytic therapy, or monoclonal antibody directed against the platelet glycoprotein IIb/IIIa receptor. All patients undergoing PTCA should receive adequate anti‐platelet therapy, including aspirin, and heparin with dosing monitored by activated clotting times (ACT). In addition, some recommend the use of ionic contrast material. When IC thrombus accumulates following intervention, initial therapy should include IC nitroglycerin followed by a combination of redilatation and IC urokinase infusion. Prolonged balloon inflations may be useful, particularly with the use of autoperfu‐sion catheters. Platelet glycoprotein IIb/IIIa receptor antagonists may prove to be beneficial in this situation as well. If the patient's clinical status deteriorates in spite of these measures, emergency coronary artery bypass graft surgery may be required.