bluuebunny/crossref_metadata_2025_split huggingface dataset:
Amiodarone: The expanding antiarrhythmic role and how to follow a patient on chronic therapy
Authors: Singh Bramah N. 
Published: February 2009

AbstractAmiodarone was introduced as an antiarrhythmic compound in the early 1970s and was approved in the U.S. for the treatment of refractory ventricular arrhythmias in late 1984. Since that time the drug has become the most widely studied antiarrhythmic compound with expanding potential indications, including maintaining stability of sinus rhythm, secondary prevention in the survivors of myocardial infarction, and prolongation of survival in certain subsets of patients with congestive heart failure. Intravenous amiodarone was introduced in the U.S. in 1995 for the control of recurrent destabilizing ventricular tachycardia or ventricular fibrillation resistant to conventional therapy. The level of comfort in its use has risen considerably in the recent past. This has stemmed from the reasonably decisive evidence that class I agents increase mortality in patients with structural heart disease. In contrast, amiodarone either reduces mortality or its effect is neutral; this is consistent with its low to negligible proarrhyfhmic actions. The drug does not aggravate heart failure and it may even increase left ventricular ejection fraction and improve exercise capacity. Above all, it is becoming increasingly evident from wider experience and from controlled clinical trials that the side‐effect profile of the drug is not as compelling an issue as it appeared to be when first used in much higher doses. Therefore, the overall objective of amiodarone therapy is to use the lowest dose that produces a defined therapeutic end point without causing serious side effects. Careful clinical surveillance in conjunction with monitoring of certain laboratory parameters and indices of efficacy at regular intervals permits the drug to be used effectively in a large number of patients who fail to respond to, or are intolerant of other antiarrhythmic compounds. Many experienced clinicians have begun to consider the use of amiodarone as first‐line therapy in certain disorders of rhythm, especially in patients with severely compromised ventricular function.
Circadian rhythmic fractal scaling of heart rate variability in health and coronary artery disease
Authors: Qtsuka Kuniaki , Cornélissen Germaine , Halberg Franz 
Published: February 2009

AbstractBackground: In clinical cardiology, heart rate variability is a putative index of autonomic cardiovascular function. Signs of reduced vagal activity are not only associated with an enhanced risk of sudden cardiac death, but such impaired heart rate variability became a new predictor of sudden cardiac death and other mortality in patients with a variety of diseased states.Hypothesis: It is postulated (1) that the time structure (chronome) of heart rate variability in clinical health includes a circadian rhythm and deterministic chaos, the latter gauged by the correlation dimension of RR intervals; and (2) that this chronome is altered in patients with coronary artery disease (CAD).Methods: From 24‐h Holter records of 11 healthy controls and 10 patients with CAD, 500‐s sections around 02:00, 06:00, 10:00, 14:00, 18:00 and 22:00 hours were analyzed for smoothed RR intervals sampled at 4 Hz. Correlation integrals were estimated for embedding dimensions from 1 to 20 with a 1.0‐s time lag, using an algorithm modified from Grassberger and Procaccia. The Wilcoxon signed‐rank test compares circadian end points assessed by cosinor between the CAD patients and age‐matched controls.Results: A circadian rhythm characterizes the correlation dimension of healthy subjects peaking during the night (p «0.005). Patients with CAD have a lowered correlation dimension (p « 0.05) and an altered circadian variation which requires the consideration of an approximately 12‐h (circasemidian) component.Conclusion: The results demonstrate the sensitivity of circadian rhythms for the detection of disease. A partial 24‐ to 12‐h (circadian‐to‐circasemidian) frequency multiplication (or partial variance transposition) in CAD of the correlation dimension, apart from being a potential clue to the etiology of the disease, adds a new feature to a chronocardiology combining, with the fractal scaling, an assessment of circadian and circasemidian components as measures of predictable variability to be tested for use in diagnosis, prognosis, and as putative guides to treatment timing.
Atrial fibrillation: A review of mechanism, etiology, and therapy
Authors: Mackstaller Lorraine L. , Alpert Joseph S. 
Published: February 2009

AbstractThe prevalence of elderly individuals in the populations of developed countries is increasing rapidly, and atrial fibrillation (AF) is quite common in these elderly patients: currently, 11% of the U.S. population is between the ages of 65 and 85 years; 70% of people with AF are between the ages of 65 and 85 years. AF causes symptoms secondary to hemodynamic derangements that are the result of increased ventricular response and loss of atrial booster function. AF can lead to reversible impairment of left ventricular function, cardiac chamber dilatation, clinical heart failure, and thromboembolic events. AF requires treatment in order to prevent these potential complications. Type Ia, Ic, and III antiarrhythmics are capable of converting AF to normal sinus rhythm (NSR). Amiodarone has the greatest efficacy and safety for converting AF and maintaining NSR while digoxin and verapamil are ineffective in restoring NSR. Quinidine, flecainide, disopyramide, and sotalol have also been shown to maintain NSR after conversion of AF. Proarrhythmia is a definite concern with the latter four agents. Alternative therapy for AF includes anticoagulation with warfarin or aspirin for the prevention of thromboembolic events, and a variety of agents to control the ventricular response. All medications used to treat AF carry significant risks in the elderly, whether from proarrhythmia, overdosing because of compliance errors, or hemorrhage secondary to anticoagulation. Treatment of AF must be based on a careful risk‐benefit evaluation. The physician must know the capability of the particular patient as well as drug mechanisms and effects in the elderly. The decision to convert patients from AF to NSR or to leave the patient in AF and control the ventricular response represents a complex intellectual challenge. Factors favoring one or the other of these two clinical strategies are discussed. Multicenter clinical trials, for example, the Atrial Fibrillation Follow‐up Investigation Rhythm Management (AFFIRM) trial, are currently underway to assess various clinical strategies for maintenance of NSR following conversion from AF. Amiodarone is one of the drugs under investigation.
Pulmonary hypertension: Newer concepts in diagnosis and management
Authors: Moraes Denzil , Loscalzo Joseph 
Published: February 2009

AbstractPulmonary hypertension comprises a family of disorders occurring as a primary disease or as a complication of a large number of respiratory and cardiac diseases. Pulmonary hypertension is present when pulmonary artery pressure or mean pressure exceeds 30 mmHg or 20 mmHg, respectively. Underlying the hemodynamic changes that result in pulmonary hypertension, whether from hypoxia, acidosis, increased pulmonary blood flow, increased shear stress, or idiopathic causes, is a dysfunctional vascular endothelium. In this review, the role of the history and physical examination in the initial assessment is emphasized. Newer diagnostic modalities, such as subselective pulmonary angiography and ultrafast computed tomography scanning, are reviewed. Low‐flow oxygen, anticoagulation, and calcium‐channel blockade are presented as accepted therapeutic modalities. Inhaled nitric oxide and prostacyclin infusion are presented as newer therapies that may be useful given the limited availability of donor organs for heart‐lung transplantation. Future therapeutic strategies are likely to develop from advances in vascular biology.
What can we learn from exercise testing beyond the detection of myocardial ischemia?
Authors: Weber Karl T. 
Published: February 2009

AbstractNoninvasive cardiopulmonary exercise (CPX) testing has proven useful in the assessment of heart and lung disease, including cardiac and ventilatory reserves. CPX includes the monitoring of respiratory gas exchange, O2 uptake and CO2 production, together with minute ventilation and its components—tidal volume and respiratory rate—together with surveillance of electrocardiography and blood pressure during supervised, incremental exercise. Exercise responses in anaerobic threshold and/or maximal O2 uptake are used to grade functional capacity objectively and to predict cardiac reserve (exercise cardiac output), which grades the severity of chronic cardiac or circulatory failure. CPX also serves to distinguish primary cardiac from ventilatory‐based exertional dyspnea.
Reverse remodeling in heart failure with intensification of vasodilator therapy
Authors: Levine T. Barry , Levine Arlene B. , Keteyian Steven J. , Narins Barbara , Lesch Michael 
Published: February 2009

AbstractBackground: Heart failure therapy with beta‐receptor blockade has been shown to effect a partial reversal of left ventricular (LV) remodeling in heart failure.Hypothesis: We tested the hypothesis that, in the absence of beta blockade, uptitration of angiotensin‐converting enzyme (ACE) inhibitor and nitrate therapy over conventional dosages would improve symptoms as well as LV function in patients with severe heart failure.Methods: For patients with nonischemic or ischemic cardiomyopathy, intensive high‐dose angiotensin‐converting enzyme inhibitor and nitrate therapy was uptitrated. Echocardiograms were obtained semiannually and evaluated in a blinded fashion. Of 99 patients in the study, aged 55 ± 13 years, with heart failure for 5.2 ± 3.1 years, 74 were men, 69 were Caucasian, and 34 had ischemic cardiomyopathy. The final dosage of enalapril was 40 ± 23 mg/day and of isosorbide dinitrate it was 153 ±127 mg/day.Results: Initial New York Heart Association classification improved from 2.8 ± 0.9 to 1.7 ± 0.9 (p<0.001) in 2.7 years of follow‐up. Of the 99 patients, 72 further improved their ejection fraction. For the whole group, ejection fraction increased from 21 ± 9% to 30 ± 13% in 6 months (p>0.001), with are‐duction in LV end‐diastolic size from 6.6 ± 0.9 to 6.3 ± 1.0 cm (p = 0.002), and a decrease in the severity of mitral regurgitation from mild/moderate to only mild. Resting heart rate declined with no change over time in systemic systolic blood pressure. Final ejection fraction for nonischemic patients (n = 65) was 36 ± 16% versus 23 ± 9% for the ischemic population.Conclusion: Uptitration of high‐dose ACE inhibitor and nitrate therapy to higher doses is well tolerated in severe heart failure, further improves both clinical status and LV systolic function, and is more effective in nonischemic than in ischemic cardiomyopathy.
Nitric oxide and cardiac failure
Authors: Ikeda Uichi , Shimada Kazuyuki 
Published: February 2009

AbstractCardiac myocytes express two types of nitric oxide (NO) synthase, eNOS and iNOS. eNOS activity is regulated by the contractile state of the heart, while iNOS expression is induced by cytokines. Nitric oxide induced by cytokines causes negative inotropic and lethal effects on cardiac myocytes. Expression of iNOS in the myocardium is increased in patients with dilated cardiomyopathy with clinical evidence of heart failure. Several neurohumoral factors activated in chronic heart failure augment cardiac iNOS expression and could cause cardiac dysfunction and cell damage.
Nonneoplastic diseases of aorta and pulmonary trunk—Part iv
Authors: Waller Bruce , Waller Bruce F. , Clary James D. , Rohr Todd 
Published: February 2009

AbstractThis five‐part review focuses on selected nonneoplastic diseases of the aorta and pulmonary trunk. Because many more diseases affect the aorta compared with the pulmonary trunk and right and left main pulmonary arteries, most of this review will be devoted to disorders of the aorta. Part IV of the series discusses cystic medial degeneration, trauma, and congenital diseases of the aorta.
Hemodynamic action of captopril in coronary patients with heart failure tolerant to nitroglycerin
Authors: Störk Thomas , Eichstädt Hermann , Möckel Martin , Gareis Ragnar , Bodemann Thomas , Möller Reinhold 
Published: February 2009

AbstractBackground:At present there is little dispute that clinical tolerance of organic nitrates occurs during long‐term treatment of patients with stable angina pectoris and congestive heart failure.Hypothesis:Captopril exerts a favorable hemodynamic effect in coronary patients with heart failure who are clinically tolerant to nitroglycerin.Methods: Development of nitrate tolerance was observed during intravenous nitroglycerin treatment (10 mg/h) in 16 of 19 patients (7 women, 12 men; mean age 56 ± 8 years) with coronary heart disease [stenosis ≥ 75%, New York Heart Association (NYHA) classes II–III). The criterion applied was a loss of efficacy of at least 50% with regard to mean pulmonary capillary wedge pressure compared with the maximum effect of nitrate. The effect of captopril (50 mg p.o.) was determined in a blank test. Captopril (50 mg p.o.) was administered again at the stage of clinically manifest nitrate tolerance.Results:Compared with the effect of captopril alone, significantly more pronounced reductions in mean pulmonary capillary wedge pressure (33% compared with 27%) and in mean pulmonary arterial pressure (36% compared with 17%) and significantly greater increases in cardiac index (14% compared with 7%) and stroke work index (34% compared with 18%) (p < 0.05 in each case; Wilcoxon test for linked random samples) were measured. Maintaining nitroglycerin infusion, the effect of captopril (at least 90% of the maximum effect) lasted for 123 ± 24 min. The baseline values (at least 75% decline in the effect of captopril) were only reached after 369 ± 34 min.Conclusion:The results document a favorable hemodynamic effect of captopril in nitrate tolerance which is significantly better than that of captopril alone.
Increased adhesiveness of white blood cells in patients with unstable angina: Additional evidence for an involvement of the immune‐inflammatory system
Authors: Leibovitz Eyal , Hertz Yizhak , Liberman Eliezer , Sclarovsky Samuel , Berliner A.S. 
Published: February 2009

AbstractBackground: Data are being accumulated on the presence of inflammatory response in patients with acute coronary syndromes.Hypothesis: The study was undertaken to confirm that the adhesive state of the peripheral blood leukocytes can provide information on an inflammatory process in patients with unstable angina pectoris.Methods: The study included 21 patients with unstable angina, 32 patients with stable angina, and 13 patients with chest pain and no evidence of coronary artery disease.Results: The percentage of aggregated leukocytes in patients with unstable angina (5.8 ± 3.2%) was significantly (p < 0.02) increased compared with that of patients with no evidence of active coronary disease (3.2 ± 2.6%).Conclusion: Additional evidence for an existing smoldering inflammatory process in unstable angina pectoris can be provided by testing the percentage of aggregated leukocytes in peripheral blood.
Nonneoplastic diseases of aorta and pulmonary trunk—Part V
Authors: Waller Bruce F. , Clary James D. , Rohr Todd 
Published: February 2009

AbstractThis five‐part review focuses on selected nonneoplastic diseases of the aorta and pulmonary trunk. Because many more diseases affect the aorta compared with the pulmonary trunk and the right and left main pulmonary arteries, most of this review will be devoted to disorders of the aorta. Part V of this five‐part series on diseases of the aorta and the pulmonary trunk focuses on nonneoplastic diseases of the pulmonary trunk and the right and left main pulmonary arteries.
The Importance of lowering cholesterol in patients with coronary heart disease
Authors: Eisenberg Daniel 
Published: February 2009

AbstractPatients with prior manifestations of cardiovascular disease account for about 50% of all myocardial infarctions and 70% of deaths due to coronary disease. The benefits of lowering elevated cholesterol levels in patients with coronary disease are well documented. Recent clinical trials indicate that these benefits, in terms of reduced risk of cardiovascular morbidity and mortality, extend even to patients with “average” cholesterol levels and support the importance of reaching a target low‐density lipoprotein cholesterol level of ≤ 100 mg/dl. These findings argue in favor of attaining and maintaining optimal lipid targets for secondary (and primary) prevention of atherosclerotic vascular disease in patients at risk.
Colchicine for large pericardial effusion
Authors: Adler Yehuda , Finkelstein Yaron , Assali Abid , Guindo Josep , Bayes‐Genis Antoni , Luna Antony Bayes De , Khouri Asaad 
Published: February 2009

AbstractOn the basis of our reported experience with colchicine for recurrent pericarditis, we administered colchicine to two patients with large pericardial effusions complicating idiopathic pericarditis. The first was a 26‐year‐old male who showed clinical deterioration following emergency pericardiocentesis and aspirin (3 g/day) for 10 days; the second was a 2‐year‐old girl who was unsuccessfully treated with aspirin (100 mg/kg/day) for 2 weeks, followed by corti‐costeroids for 7 months. Administration of colchicine (1 mg/ day) instead of aspirin in the first case, and with a rapid tapering‐off of the corticosteroids in the second case, led to complete regression of the pericardial effusion on echocardiography within 1 week and 1 month, respectively. Colchicine was discontinued after 1 month in the first patient and was continued for 6 months in the child. Neither has had a recurrence at 24 and 6 months of follow‐up, respectively. No side effects of colchicine were observed. We conclude that colchicine may be effective in the treatment of large pericardial effusion when therapy with nonsteroidal anti‐inflammatory drugs and/or corticosteroids fails.
Identifying high yield sources of patients with coronary artery disease for clinical trials: Lessons from the asymptomatic cardiac ischemia pilot (ACIP) experience
Authors: Handberg‐Thurmond Eileen , Baker Ann , Coglianese Mary Ellen , Forman Sandra , Pepine Carl J. , Geller Nancy , Chaitman Bernard ,   For The ACIP Study Group
Published: February 2009

AbstractBackground and hypothesis: Successful recruitment strategies for ischemic heart disease (IHD) clinical trials must identify high yield sources and efficient methods for selecting patients likely to have coronary artery disease (CAD) and ischemia, but such information is lacking.Methods: Data from the recently completed Asymptomatic Cardiac Ischemia Pilot (ACIP) Trial were used as a model contemporary CAD/IHD trial to determine the relative patient yields, within a specific time frame, for various recruitment sources.Results: Over 15 months, a total of 88,881 patient records was screened at 10 sites. The highest yield source was found by screening records of patients directly referred by a physician for possible study entry. This source accounted for 595 of 814 or 73% of potential patients and for 30% of patients eventually randomized. The largest volume of potential patients was observed from coronary angiographic laboratory record screening, and this source accounted for 39% (n = 7,542) of potential patients and for 24% of those randomized. The exercise electrocardiography (ECG) laboratory patient records yielded only 16% (5,340/33,784) of potential patients and 35% of patients randomized, but this source required considerably more time and resources for screening.Conclusions: Considering that time and resources for screening are fixed by budget in any trial, there is a need to balance high volume‐moderate yield sources with low volume‐high yield sources in order to optimize recruitment in future larger scale trials, and these data provide information and direction to focus such screening efforts.
Electrocardiographic crotchets or common errors made in the interpretation of the electrocardiogram
Authors: Willis Hurst J. 
Published: February 2009

AbstractIrritating errors are called crotchets. This paper discusses the following electrocardiographic crotchets: memorizing patterns rather than using basic principles, failure to use the electrocardiogram as a diagnostic tool, failure to correlate all available data, failure to appreciate the limitation of the computer interpretation, failure to appreciate the diagnostic value of P‐wave abnormalities, the identification and misuse of abnormal Q waves, the misuse of left or right axis deviation of the QRS complexes, the misuse of the amplitude of the QRS complexes as a sign of left ventricular hypertrophy, identification of left ventricular hypertrophy, failure to identify uncomplicated and complicated bundle‐branch block, failure to identify secondary and primary T‐wave ibnormalities, failure to identify secondary and primary S‐T abnormalities, and lack of knowledge of the U waves.
Left ventricular diastolic collapse in low‐pressure cardiac tamponade
Authors: Dwivedi Sudhanshu Kumar , Saran Ramkirti , Narain Varun Shanker 
Published: February 2009

AbstractA case of systemic hypotension with volume depletion not responding to intravenous fluids was found to have features of cardiac tamponade on two‐dimensional (2‐D) echocardiography. Intracardiac pressures were normal on cardiac catheterization. An interesting observation was the presence of left ventricular (LV) collapse on 2‐D echocardiography. To the authors' best knowledge, such a case of low‐pressure cardiac tamponade with LV collapse has not been reported earlier.
Hypocalcemic heart failure: A reversible form of heart muscle disease
Authors: Suzuki Takaaki , Ikeda Uichi , Fujikawa Hideyjuki , Shimada Kazuyuki , Saito Ken 
Published: February 2009

AbstractThis paper reports the case of a 53‐year‐old woman with hypocalcemia‐induced reversible cardiomyopathy. Laboratory tests showed hypocalcemia caused by idiopathic hypoparathyroidism. Her left ventricular dysfunction persisted for a long period even after normalization of the serum calcium level. Observations suggest that physicians should be aware that hypocalcemia can be a reversible cause of cardiomyopathy and congestive heart failure.