bluuebunny/crossref_metadata_2025 huggingface dataset:
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

Background: 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

Heart 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

Hypothesis: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

A 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

Malignant 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

The 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

Background 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

Background 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

Background 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

Hypothesis: 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

Knowledge 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

This 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

With 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.
Effect of enalapril initiated early after acute myocardial infarction on heart failure parameters, with reference to clinical class and echocardiographic determinants
Authors: Edner Magnus , Bonarjee Vernon V. S. , Nilsen Dennis W. T. , Berning Jens , Carstensen Steen , Caidahl Kenneth
Published: February 2009

Background and hypothesis: Although the angiotensin‐converting enzyme inhibitor enalapril has recently been shown to reduce mortality and the need for hospitalization in patients with left ventricular dysfunction and congestive heart failure, this drug was found to have no significant impact on short‐term mortality after acute myocardial infarction (AMI) in the CONSENSUS II trial. The effect of enalapril initiated early after AMI on clinical and echocardiographic determinants of left ventricular (LV) function was studied in a subset of patients from CONSENSUS II

Methods: Symptoms and signs of heart failure were classified as NYHA and dyspnea classes. Echocardiography included LV end‐systolic volumes (ESV) and end‐diastolic volumes (EDV), as well as ejection fraction (EF). wall motion index (WMI), and mitral flow indices. In all, 428 patients were included and followed for an average of 5.1 months by serial examinations, starting 2–5 days after myocardial infarction (MI) and repeated after 1 month and at the completion of the study.

Results: There was no beneficial effect of enalapril on clinically determined function. Changes (i.e. changes in NYHA class) in the functional status remained correlated with changes in echocardiographic determinants throughout the study in patients belonging to the placebo group: EDV index (r=0.36, p = 0.002, ESV index (r = 0.49, p < 0.001), EF (r = ‐0.41, p < 0.001), and WMI (r=0.29, p = 0.008). In a stepwise logistic regression model, the best baseline parameters to predict NYHA class at final visit in all patients were age (p = 0.014) and ESV index (p = 0.001).

Conclusion: Enalapril treatment for an average period of 5.1 months following MI resulted in no clinically significant beneficial effects on NYHA and dyspnea class. Changes in clinical function class were correlated with changes in echocardiographic determinants in placebo‐treated patients, but not in patients given enalapril.
Coagulation and fibrinolytic parameters in patients with pulmonary hypertension
Authors: Altman Raul , Scazziota Aleiandra , Rouvier Jorge , Gurfinkei Enrique , Favaloro Roberto , Perrone Sergio , Fareed Jawed
Published: February 2009

Background: Vascular endothelium reacts to various patho‐physiologic stimuli by releasing several autocoids and cyto‐kines that can be used along with the coagulation and fibrinolytic markers for the diagnosis of hemostatic alterations. Several newer markers for vascular distress, such as tissue plasminogen activator (TPA), tissue plasminogen activator inhibitor‐ I (PAI‐1), TPA/PAI‐1 complex, and the newly reported inhibitor of the coagulation process, namely, tissue factor pathway inhibitor (TFPI), have been implicated in the pathogenesis of pulmonary hypertension.

Methods: To investigate the behavior of endothelial cells at basal and time‐dependent venous stasis‐induced changes, various markers were measured in patients with primary and secondary pulmonary hypertension and compared with healthy human volunteers (controls) without any family history of thromboembolism or history of hypertensive disorders. The right atrial pressure (RAP) and pulmonary arterial pressure were measured and the hemostatic parameters were correlated to determine the relevance of these parameters with the alterations in the present indices.

Results: A fibrinolytic deficit exists in patients with pulmonary hypertension, indicated by the prolongation of the euglobulin clot lysis time at basal conditions and after the venous occlusion test. This defect was mainly due to increased production of PAI‐1 by endothelium (patients 59.8 ± 22.3 AU/ml; controls 30.3 ± 14.5 AU/ml; p = 0.005). We also report for the first time that a decrease in tissue factor pathway inhibitor antigen was also observed in these patients when RAP was >9 mmHg [controls 95.6 ± 61.6 ng/ml; patients with RAP >9 mmHg 47.2 ± 19.2 ng/ml (p = 0.044); patients with RAP <9 mmHg 96.6 ± 32.4 ng/ml (p = 0.002 compared with patients with RAP > 9 mmHg)], indicating endothelial cell and hemostatic disturbances.

Conclusions: We conclude that the euglobulin clot lysis time was prolonged in patients with pulmonary hypertension compared with controls. The impairment of the fibrinolytic system was due to an elevated concentration of PAI‐1. In RAP > 9 mmHg, an additional prothrombotic factor is the decrease in plasma tissue factor pathway inhibitor antigen. It appears from this study that antithrombotic treatment is indicated in these patients.
Influence of gender on survival, mode of death, reinfarction, use of medication, and aspects of well being during a period of five years after onset of acute myocardial infarction
Authors: Herlitz John , Bångr Angela , Hartford Marianne , Karlson Björn W.
Published: February 2009

Background and hypothesis: This study was undertaken to describe prognosis during a period of 5 years after an acute myocardial infarction (AMI) in relation to gender.

Methods: All patients studied were hospitalized in a single hospital during a period of 21 months due to AMI, regardless of age and whether they were admitted to the coronary care unit or another ward. A total of 862 AMI patients [581 (67%) men and 281 (33%) women] were prospectively evaluated. Males were younger and less frequently had a history of congestive heart failure and hypertension.

Results: The overall 5‐year mortality rate was 48% among men compared with 61 % among women (p < 0.001). However, in a multivariate analysis considering age, gender, and a previous history of cardiovascular diseases, female gender was not independently associated with death. Revascularization in terms of coronary artery bypass grafting and percutaneous transluminal angioplasty did not differ significantly between men and women. The rate of reinfarction was 34% among men and 38% among women (p > 0.2).

Conclusion: During 5 years of follow‐up in a consecutive series of 862 AMI patients, women had a worse prognosis than men, with a mortality of 61 % compared with 48% (p < 0.001). However, after controlling for a number of potentially confounding prognostic factors, female gender was not independently associated with mortality.
Intravenous amiodarone is safe and seems to be effective in termination of paroxysmal supraventricular tachyarrhythmias
Authors: Cybulski J. , Kulakowski P. , Makowska E. , Czepiel A. , Sikora‐Frąc M. , Ceremużyńki L.
Published: February 2009

Background: Paroxysmal atrial fibrillation (PAF) and paroxysmal supraventricular tachycardia (PSVT) leading to hemodynamic compromise are among the most common reasons for admission to the coronary care unit (CCU) and need prompt and efficient therapy. Direct current cardioversion is the therapy of choice, but if found contraindicated or unavailable some antiarrhythmie agents are usually given to restore sinus rhythm. Many of these drugs have obvious limitations, especially in patients with acute myocardial infarction and/or heart failure.

Hypothesis: The aim of the present study was to assess the safety and efficacy of intravenous amiodarone in the acute termination of PAF or PSVT refractory to other antiarrhythmie agents in a large group of patients consecutively admitted to our CCU.

Methods: In the present study, we evaluated the safety and efficacy of amiodarone given intravenously in 142 consecutive patients with PAF or PSVT lasting < 24 h. In 37% of patients no evidence of underlying heart disease which may have caused arrhythmias were defined. A median of two other antiarrhythmic agents given prior to the first amiodarone injection had been ineffective.

Results: Sinus rhythm was restored in 91 patients (64%) (65% in the PAF group and 61% in the PSVT group). The mean time to rhythm conversion was 5.5 ± 6.1 h for patients with PAF and 1.2 ± 1.2 h for patients with PSVT. The mean dose of amiodarone administered up to conversion was 340 ± 220 mg for PAF and 220 ± 105 mg for PSVT. Except for transient first‐degree atrioventricular block in two patients, no adverse effects possibly related to amiodarone were observed (including proarrhythmia and incidence or aggravation of heart failure symptoms).

Conclusion: Amiodarone given intravenously for acute termination of supraventricular tachyarrhythmias is completely safe and seems effective. The results of this study, which is the largest ever made, indicate a need of randomized, controlled trials for the ultimate assessment of the efficacy of amiodarone in this clinical setting.
Dose‐dependent appearance and disappearance of amiodarone‐induced skin pigmentation
Authors: Kounis Nicholas G. , Frangides Christos , Papadaki Paraskevi J. , Zavras George M. , Goudevenos John
Published: February 2009

A 66‐year‐old man suffering from atrial flutter developed cutaneous blue‐gray pigmentation while receiving 600 mg of amiodarone daily for 15 months. With reduction of the dose to 100 mg, skin discoloration disappeared within 16 months, to reappear within 7 months after increasing the dose to 400 mg. Finally, the discoloration disappeared within 13 months with a dose reduction to 200 mg daily. It seems that a tissue threshold level for amiodarone exists in this patient, above which skin discoloration appears and below which it fades. Dose, duration, metabolism, macrophage transfer, and spillover saturation‐excretion may be relevant in amiodarone‐induced skin pigmentation.
Hemoptysis and unilateral intra‐alveolar hemorrhage complicating intravenous thrombolysis for myocardial infarction
Authors: Hammoudeh Ayman J. , Haft Jacob I. , Eichman Gerard T.
Published: February 2009

This report deals with a patient who developed hemoptysis due to unilateral intra‐alveolar hemorrhage after receiving tissue‐type plasminogen activator (TPA) for acute myocardial infarction; the patient had sustained an ipsilateral lung injury 2 years earlier.
Oversensing of atrial flutter in the recipient atrium of a heart transplant patient with a permanent atrial pacemaker
Authors: Woodard David A. , Conti Jamie B. , Curtis Anne B.
Published: February 2009

Sinus node dysfunction requiring permanent pacemaker implantation is a common problem following heart transplantation. There are unique problems to consider in pacing the transplanted heart. This report describes a case of far‐field sensing of atrial flutter in the recipient atrial remnanl, with resultant inhibition of the atrial pacemaker in the donor atrium, and symptomatic bradycardia. Although postulated to be a potential problem, oversensing of the recipient atrium has not been reported prior to this case. Awareness of this problem will provide for more effective pacemaker troubleshooting.
The use of dobutamine stress echocardiography for the determination of myocardial viability
Authors: Hansen Todd H. , Segar Dogglas S.
Published: February 2009

Determining the presence of viable myocardium has prognostic and therapeutic implications in the treatment of ischemic heart disease. Dobutamine stress echocardiography (DSE) is one possible technique to help identify both hibernating and stunned but viable myocardium. Low‐dose dobutamine infusion has an increased inotropic effect, while higher doses cause both inotropic and chronotropic effects. Thus, at lower doses cardiac augmentation occurs, and at higher doses regions of ischemia may be produced in the presence of significant coronary artery disease. This is manifested echocardiographically as changes in segmental wall motion. in theory, therefore, areas of viable myocardium should show improved wall motion at low doses, and areas of irreversible myocardial damage will remain akinetic. Five studies have investigated DSE for determining viability in the setting of acute myocardial infarction, thus looking for stunned but viable myocardium. DSE was shown to compare favorably with positron emission tomography and was highly sensitive and specific for predicting functional myocardial recovery. Five additional studies examined DSE for determining the presence of hibernating myocardium. The sensitivity and specificity of DSE were found to range from 71 to 92% and from 73 to 93%, respectively. The benefits of DSE include lower cost, convenience to both patient and physician, additional ancillary information, and determination of the possible need for urgent revascularization. Limitations of DSE include occasional technical difficulty in obtaining and interpreting studies and the need for larger volumes of viable myocardium to detect changes predictive of functional recovery. Larger trials are currently underway to confirm DSE as a reliable technique for determining myocardial viability.
Effects of heart rate on coronary circulation and external mechanical efficiency in elderly hypertensive patients with left ventricular hypertrophy
Authors: Ishibashi Yutaka , Shimada Tosfflo , Umeno Tetsuhiro , Yoshitomi Hiroyuki , Morioka Shigefumi , Sano Kazuya , Oyake Nobuyuki , Nosaka Susumu , Kobayashi Shigeo
Published: February 2009

Background and hypothesis: Mechanisms of heart failure in elderly hypertensive patients with hypertrophy have not been studied sufficiently. We hypothesized that impaired increment of coronary blood flow in response to increases in heart rate could be responsible for the occurrence or aggravation of heart failure.

Methods: To test this hypothesis, we measured coronary hemodynamics and lactate balance during basal conditions and atrial pacing in 21 elderly patients aged ≥ 65 years (mean 74 ± 6 years) without coronary arterial disease: 7 normoten‐sive control patients (Group 1), 7 hypertensive hypertrophic patients without a history of congestive heart failure (Group 2), and 7 patients with such history (Group 3). Coronary sinus blood flow (CSBF) was measured in coronary sinus using a thermodilution catheter.

Results: During basal conditions, heart rate did not differ among the three groups (67 ± 3 in Group 1,65 ±11 in Group 2, and 63 ± 6 beats/min in Group 3). CSBF was significantly higher in the two hypertrophic groups than in the control group, but CSBF normalized by left ventricular mass was significantly lower in both hypertrophic groups. External mechanical efficiency (EME) obtained as left ventricular work divided by myocardial oxygen consumption did not differ among groups during basal conditions (36 ± 9% in Group 1, 35 ± 8% in Group 2, and 29 ± 9% in Group 3, NS). During atrial pacing to increase heart rate by 25 ± 5% (lower) and 54 ± 6% (higher), the increases in CSBF were markedly limited in both hypertrophic groups, and the response in Group 3 was more depressed than that in Group 2. EME did not change in the control group or in Group 2, but did decrease to 21 ± 5% in Group 3 during the higher pacing rate (p <0.01 vs. basal conditions). in this group, the relationship between EME and heart rate showed a significant negative correlation (r = —0.56, p = 0.02). Lactate balance in coronary sinus blood showed a tendency to production in Group 3 during the higher pacing rate, suggesting myocardial ischemia.

Conclusion: These findings suggest that in hypertensive hypertrophic patients with a history of heart failure, the coronary circulation system is vulnerable to increasing heart rate. in medical treatment of elderly hypertensive patients, control of heart rate in addition to blood pressure control should be considered to minimize the occurrence or aggravation of heart failure.
Myocardial infarction in men aged 40 years or less: A prospective clinical‐angiographic study
Authors: Fournier J. A. , Sanchez A. , Quero J. , Fernandez‐Cortacero J. A. P. , González‐Barrero A.
Published: February 2009

Hypothesis: The study was undertaken to characterize acute myocardial infarction (AMI) in young patients.

Methods: in all, 108 consecutive Mediterranean patients with AMI (102 men and 6 women), aged ≤ 40 years, were prospectively included in this study over a period of 6.5 years. Coronary angiography was carried out within the first month and data from these patients with normal or diseased coronary arteries were compared. Clinical features, risk factors, and in‐hospital and late morbidity and mortality were evaluated.

Results: Young patients with AMI represent 4.1 % of the 2,644 patients admitted because of definite AMI during this period. The most common risk factors were cigarette smoking (94.5%) and hypercholesterolemia (48%). Location of the AMI was anterior in 37%, inferior in 57.5%, and non‐Q in 5.5%. A history of previous angina was present in 42.5% of the patients, including all seven patients with previous myocardial infarction (6.5%). However, in 52% of the patients the anginal episodes started in the week prior to the AMI. in hospital mortality and mortality during a mean follow‐up of 41 ± 23 months were 3.7 and 3.8%, respectively. The Kaplan‐Meier actuarial curve assessed on 97 of 104 survivors was 100 and 94% at 1 and 5 years, respectively. Coronary arteries were angiographically normal in 17 (20%) of 87 survivors. Compared with young patients who had obstructive lesions, this subset had a lower age and fewer risk factors, reinfarction (p<0.05), and late angina (p<0.01), but development of congestive heart failure and survival were similar in both groups.

Conclusion: These data suggest that young patients with AMI are very frequently heavy smokers, have a high incidence of angiographically normal coronary arteries, and that the short‐ and long‐term prognosis is excellent.
Nonatherosclerotic causes of coronary artery narrowing—Part III
Authors: Waller Bruce F. , Fry Edward T. A. , Hermiller James B. , Peters Thomas , Slack John D.
Published: February 2009

Approximately 5% of patients with acute myocardial infarction do not have atherosclerotic coronary artery disease but have other causes for their luminal narrowing. The third part of this three‐part review of nonatherosclerotic causes of coronary narrowing focuses on coronary vasculitis, infectious diseases, Kawasaki's disease, metabolic disorders, metastatic disease, and substance abuse (cocaine). coronary arteritis: (1) focal artery necrosis with or without calcification, (2) acute coronary artery thrombosis or recanal‐ized thrombus unassociated with underlying atherosclerotic plaque, (3) rupture of the vessel wall unassociated with trauma or an interventional procedure, (4) coronary artery wall thickening with secondary luminal narrowing, and (5) wall thinning with aneurysm formation.3 Specific coronary lesions also may be seen in specific systemic diseases (e.g., pol‐yarteritis nodosa).
Sustained ventricular tachycardias associated with myotonic dystrophy
Authors: Tamura Koji , Tsuji Hisako , Matsui Yumie , Masui Akira , Hikosaka Makoto , Karakawa Masahiro , Iwasaka Toshiji , Inada Mitsuo
Published: February 2009

Patients with myotonic dystrophy are reported to have a higher frequency of sudden death than the general population. Although causes of sudden death in myotonic dystrophy are suggested to be due to conduction defects progressing, the HV interval cannot predict whether conduction system disease would develop or progress. We report two cases of myotonic dystrophy complicated with sustained monomorphic ventricular tachycardias (VT), which can cause sudden death. in Case No. 1, although the patient was treated successfully for sustained VT with verapamil in elec‐trophysiologic studies, another sustained VT was confirmed 2 years later. in Case No. 2, the patient showed decreased left ventricular ejection fraction and late potentials, and induced sustained VT that was identical to clinically documented VT. Although VT is believed to be rare in patients with myotonic dystrophy, these cases suggest that VT is a possible cause of sudden death.
Evaluation of left ventricular relaxation using the continuous‐wave doppler velocity profile of aortic regurgitation: Noninvasive measurement of left ventricular negative dP/dt and time constant
Authors: Honda Yuka , Yokota Yoshiyuki , Yokoyama Mitsuhiro
Published: February 2009

Background: The maximal negative dP/dt [max (‐)dP/dt] and time constant (T) are useful indices for evaluating left ventricular (LV) relaxation, but they require invasive procedures.

Hypothesis: The purpose of this study was to obtain max (‐)dP/dt and T using the continuous‐wave Doppler aortic regurgitation velocity curve (AR‐CW) noninvasively. Using the Bernoulli equation, the AR‐CW allows accurate determination of the pressure gradients (PG) between the aorta and the left ventricle.

Methods: In 10 patients with trivial to mild AR, the rising segment of the AR‐CW reflecting LV pressure decrease was digitized with the cardiac image analysis system. Transpulmonary contrast‐enhanced Doppler echocardiography was used in three patients to obtain intense velocity envelope. The PG curve and the first derivative curve were reconstructed and the maximal point of the first derivative curve, which is consistent with max (‐)dP/dt, was termed as maximal rate of pressure fall (maxRPF). As T (calculated according to the method of Weiss) can be obtained from T=Pm/max (‐)dP/dt [Pm: LV pressure at the phase of max (‐)dP/dt], we calculated T from Pm/maxRPF (Pm=dicrotic notch pressure ‐ 4Vm2) (Vm: AR velocity at the phase of maxRPF).

Results: The Doppler‐derived maxRPF and T (Td) approximated the catheter‐derived max (‐;)dP/dt and T (y=0.85x+ 245, r=0.97, p<0.001, y=0.79x+4, r=0.87, p<0.001). In addition, dobutamine echocardiography was performed in nine patients showing increased maxRPF and decreased Td, indicating improvement of LV relaxation.

Conclusion: These Doppler‐derived new indices are sufficiently useful to evaluate LV relaxation noninvasively.
Hemodynamic time course of acute and chronic isosorbide dinitrate treatment at rest and during exercise in patients with stable ischemic heart disease
Authors: Jørgensen Lars H. , Thaulow Erik , Refsum Harald E.
Published: February 2009

Hypothesis: The study was undertaken to establish differences between venous and arterial isosorbide dinitrate (ISDN) effects during acute and chronic treatment, hemodynamics at rest, and during supine exercise.

Methods: These effects were assessed invasively in 16 patients with stable ischemic heart disease before and at hourly intervals for 4 h after administration of peroral 30 mg ISDN. Eight patients were previously untreated (acute group), and eight were treated with 30 mg ISDN asymmetrically b.i.d. for two weeks (chronic group).

Results: Prior to ISDN administration, right atrial, mean pulmonary artery, pulmonary artery wedge, and mean arterial pressure (RAP, MPAP, PAWP, and MAP) rose from normal resting to pathologic values during exercise. One h after ISDN administration, all exercise pressures were normalized (p<0.001). During the following 3 h, exercise RAP rose similarly in both groups (p<0.01), while MPAP rose particularly in the chronic group (p<0.001). Exercise PAWP and MAP, however, remained low in the acute group, but increased markedly in the chronic group (p<0.01), particularly from the third to the fourth hour after ISDN.

Conclusion: The daily, asymmetric administration of 30 mg ISDN b.i.d. maintained beneficial, anti‐ischemic effects for 2 to 3 h after a morning dose of the drug, but thereafter attenuation of the effects occurred in the arteries but not in the veins.
High prevalence of repolarization abnormalities in children with simple ventricular ectopy
Authors: Miga Daniel E. , Case Christopher L. , Gillette Paul C.
Published: February 2009

Background: Premature ventricular contractions (PVCs) may occur in 0.3 to 2.2% of routine resting electrocardiograms (ECGs) in children with structurally normal hearts.

Hypothesis: This study tests the hypothesis that repolarization abnormalities are present more frequently on the surface ECG in pediatric patients with benign ventricular ectopy.

Methods: A retrospective study was performed examining 32 children with benign ventricular ectopy and structurally normal hearts. The surface ECG was carefully reviewed, concentrating on repolarization abnormalities as evidenced by a prolonged QTc, a prolonged JTc, and/or an abnormal T‐wave vector. QTc was calculated using Bazett's formula and considered prolonged if >440ms, and the JTc was calculated using a formula analogous to Bazett's formula and considered prolonged if >340 ms. The T‐wave vector was considered normal if between 0 to +90°, concordant with the frontal QRS axis and within 60°of the QRS axis. There were 13 females (41%) and 19 males (59%) with an average age of 9.1 years (range 1‐16.1 years). These patients were then compared with age‐ and gender‐matched controls. Fourteen of 32 study patients (44%) and 2 of 32 controls (6%) had evidence of repolarization abnormalities.

Results: Using $cH2 analysis, there was a significant difference between groups (p=0.0005). No patient had an abnormal T‐wave vector and there were no other significant ECG abnormalities. There was no significant relationship between repolarization abnormalities and patient gender or age.

Conclusion: A significant percentage (44%;p=0.0005) of children with benign ventricular ectopy have associated repolarization abnormalities as evidenced by a prolonged QTc and/or JTc. This finding suggests that children with “benign PVCs” may have repolarization changes indicative of underlying substrate abnormalities.
On‐line evaluation of systolic performance by densitometry in digital left ventriculography
Authors: Lehmkuhl Hans , Altstidl Robert , Machnig Thomas , Bachmann Kurt , Blunck Birgit , Barth Karl
Published: February 2009

The angiocardiographic evaluation of left ventricular end‐diastolic (LVEDV) and end‐systolic (LVESV) volumes and ejection fraction (EF) is routinely performed by the area‐length method (ALM) but may lead to erroneous results. Digital imaging in real time allows densitometric procedures of determining left ventricular (LV) performance to be applied alternatively. In this study, we present densitometric algorithms for the analysis of LVEDV, LVESV, and EF from digital image data, establish accuracy and reproducibility, and determine value and limitations in comparison with ALM in single‐plane 30°right anterior oblique (RAO) projection. A linear relationship between iodine depth and measured densities is mainly burdened with scatter radiation and beam hardening which reduce primary radiation and suppress iodine depth. However, facilities such as deconvolution and correction algorithms are capable of reducing these sources of error. In the present study, computer‐analyzed contrast images of iodine‐filled wedges and spheres showed a near‐linear relationship between iodine depth between 50‐100 mg/cm2 and measured densities. Contrast images of heart casts and LV an‐gio‐grams of 54 patients were obtained with a digital image acquisition and processing system, and evaluated by two in dependent observers. The phantom study resulted in significantly (p≤0.01) better densitometric standard errors of estimate for volumes [3.3 ml densitometry (DENS) vs. 8.9 ml (ALM)] and simulated EF [4.3% (DENS) vs. 7.8% (ALM)] than ALM. The standard error of estimate for the comparison between both methods was 8.4 ml for volumes and 7.5% for EF. Densitometric volumes tended to underestimate volumes calculated by ALM. The angiographic study of patients demonstrated significant correlations between both methods (LVEDV r = 0.78, LVESV r = 0.83, total volumes: r = 0.89;EF r = 0.88). The standard errors of estimate can be ascribed to systematic, method‐related errors of both DENS and ALM (LVEDV ± 28.9 ml, LVESV ± 23.4 ml, total volumes (EDV and ES V) ± 27.1 ml; EF ± 8.1 %). The intra‐ and interobserv‐er variability, respectively, exhibited significantly smaller (p ≤0.01 and p ≤0.05, respectively) standard errors of estimate for densitometric EF [4.6% (DENS) vs. 8.5% (ALM) and 7.1% (DENS) vs. 10.3% (ALM), respectively]. Inclined but not significant differences were found for LVEDV and LVESV. In conclusion, the data presented indicate that the calculation of LV volumes and EF in digital left ventriculography may be performed accurately by densitometric calculation in single‐plane 30°RAO projection. Minor underestima‐tions in densitometric volume determination may be anticipated in the evaluation of LV geometry.
Coronary artery and saphenous vein graft remodeling: A review of histologic findings after various interventional procedures—Part I
Authors: Waller Bruce F. , Orr Charles M. , Vantassel James , Fry Edward , Hermiller James , Grider Larry D.
Published: February 2009

Catheter balloon angioplasty is a well accepted form of nonsurgical treatment of acutely and chronically obstructed coronary artery vessels. It is also the centerpiece for various new intervention techniques. Their morphologic effects on the site of obstruction has been termed “remodeling.” Part I of this six‐part series focuses on mechanisms of remodeling after various interventional techniques, particularly balloon angioplasty.