bluuebunny/crossref_metadata_2025_split huggingface dataset:
Are technetium‐99m‐labeled myocardial perfusion agents adequate for detection of myocardial viability?
Authors: Caner Biray , Beller George A. 
Published: February 2009

AbstractThe noninvasive assessment of myocardial viability in patients with coronary artery disease and depressed left ventricular function has proven clinically useful for identifying those patients with ischemic cardiomyopathy who benefit most from coronary revascularization. Thallium‐201 (201T1) imaging at rest has been the radionuclide imaging technique most often utilized for distinguishing viable myocardium from scar. However, new technetium‐99m (99mTc) perfusion agents such as 99mTc‐sestamibi and 99mTc‐tetrofosmin have emerged as alternatives to 201T1 for imaging of regional myocardial perfusion. Whether these new agents, which have better physical properties for imaging with a gamma camera than 201T1, are valid for use in assessing myocardial viability is still uncertain. Recent clinical studies have demonstrated that these agents, when imaged using quantitative SPECT, can identify patients with myocardial hibernation who exhibit improved regional systolic function following revascularization. Experimental laboratory studies have shown that the uptake of 99mTc‐sestamibi and 99mTc‐tetrofosmin in ischemic myocardium is only slightly lower than the uptake of 201T1. These 99mTc‐labeled agents remain bound intracellularly in mitochondria of viable myocytes under conditions of myocardial stunning and short‐term hibernation, producing severe myocardial asynergy. With respect to determination of viability, the inferior wall region is at times problematic since attenuation of 99mTc‐sestamibi and 99mTc‐tetrofosmin is greatest in this area. Demonstration of preserved systolic thickening on ECG‐gated SPECT images is indicative of viability in the instance of decreased regional 99mTc counts due to attenuation and not scar. Administration of nitrates prior to tracer injection improves the sensitivity for identifying viable myocardial segments using rest imaging with 99mTc‐sestamibi or 99mTc‐tetrofosmin.Thus, it appears that the new 99mTc perfusion imaging agents can be successfully employed for the determination of myocardial viability in the setting of severe regional dysfunction and chronic coronary artery disease. The greater the myocardial uptake of these agents in the resting state, the greater the probability of improved systolic function after coronary revascularization.
Dextrocardia and corrected transposition of the great arteries (I, D, D) in a case of kartagener's syndrome: A unique association
Authors: Bitar Fadi F. , Shbaro Roula , Mroueh Salman , Yunis Khalid , Obeid Mounir 
Published: February 2009

AbstractKartagener's syndrome (KS) usually includes mirror‐image dextrocardia. The incidence of congenital heart disease in KS is comparable with that in the general population. This paper reports on a case of Kartagener's syndrome associated with dextrocardia, corrected transposition of the great arteries (I, D, D), ventricular septal defect, and valvar pulmonary stenosis in an 8‐year‐old girl.
Noninvasive coronary angiography by contrast‐enhanced electron beam computed tomography
Authors: Achenbach Stephan , Moshage Werner , Bachmann Kurt 
Published: February 2009

AbstractElectron beam computed tomography (EBCT) is a cross‐sectional imaging method with high temporal and spatial resolution. So far, it has mainly been applied for the detection of coronary artery calcifications which permit the very sensitive detection of coronary atherosclerosis even in the very early stages. However, after intravenous injection of a contrast agent, EBCT also permits the direct visualization of the coronary artery lumen. For these investigations, a volume data set is acquired that consists of 40 axial cross‐sections of the heart (3 mm slice thickness). To evaluate the coronary arteries as to the presence of stenoses and occlusions, various forms of postprocessing, including shaded surface display, maximum intensity projection, and multiplanar reconstruction, are applied. The sensitivities and specificities for the detection of coronary artery stenoses and occlusions are about 90%. Best results are obtained for coronary artery bypass grafts, the left main coronary artery, and the left anterior descending coronary artery, while reduced image quality impairs the results for the right coronary artery and the left circumflex coronary artery.
Influence of smoking status on progression of endothelial dysfunction
Authors: Pepine Carl J. , Schlaifer Jay D. , Mancini G. B. John , Pitt Bertram , O'Neill Blair J. , Haber Harry E. 
Published: February 2009

AbstractBackground: Cigarette smoking is a major risk factor for developing coronary artery disease and is associated with increased coronary morbidity and mortality in patients with established atherosclerosis. This report describes the influence of smoking on coronary endothelial function in normotensive patients with coronary artery disease, but without left ventricular dysfunction, severe hypercholesterolemia, or insulin‐dependent diabetes mellitus.Methods: Placebo‐treated patients (n = 54) from a larger study assessing coronary endothelial function were classified at baseline as smokers or nonsmokers for this subgroup analysis. Patients underwent coronary angiography at baseline and again after 6‐month follow‐up.Results: At baseline, there was a trend for a greater decrease in target segment diameter (n = 54) in smokers compared with nonsmokers (‐ 17.2 ± 5.3% vs. ‐8.0 ± 2.5%, acetylcholine 10−4 mol/1). All measured coronary artery segments (n = 202) showed similar responses (‐ 7.3 ± 2.7% vs. ‐ 3.8 ± 1.3%, acetylcholine 10−4 mmol/1, for smokers vs. nonsmokers, respectively). After 6 months, smokers showed an even greater vasoconstrictor response to acetylcholine whereas nonsmokers did not (‐ 21.7 ± 5.3% vs. ‐ 8.3 ± 2.5%, acetylcholine 10−4 mmol/1). The vasodilatory response to nitroglycerin was similar in smokers and nonsmokers.Conclusions: In current smokers, a marked decline in endothelium‐dependent vasomotor response was observed over a 6‐month period.
Atheromatous plaque reflects serum total cholesterol levels: A comparative morphologic study of endarterectomy coronary atherosclerotic plaques removed from patients from the southern part of India and caucasians from Ottawa, Canada
Authors: Varghese P. Jacob , Walley Virginia , Arumugam Sarasa Bharati , Cherian K. M. , Farb Andrew , Virmani Renu 
Published: February 2009

AbstractBackground: Natives of South India have a very high incidence of coronary artery disease, despite low calorie and fat intake.Hypothesis: This study was undertaken to determine whether morphologic features of atheromatous plaque reflect the serum total cholesterol.Methods: Fifty‐three endarterectomy specimens from patients (mean age 47 ± 9 years, mean cholesterol 203 ± 47 mg/dl) obtained from one cardiac surgeon working in a single institution in South India were evaluated. Morphologic findings were compared with 40 endoarterectomy specimens obtained from age‐matched Caucasians from Ottawa, Canada, with a reported mean cholesterol of 262 ± 47 mg/dl. Morphometric measurements of the vessel size, percent stenosis, and the various components of the atherosclerotic plaque were determined by computerized planimetry.Results: The vessel size was smaller in the Indian than in the Canadian population (4.6 ± 2.9 vs. 5.6 ± 3.0 mm2, p = 0.07), the plaque area was less (4.3 ± 2.3 vs. 5.3 ± 2.8 mm2, p = 0.055) and the calculated percent stenosis was significantly less (93 vs. 96%, p = 0.028). Of all the parameters evaluated, only necrotic core in the Indian population (7.1 ± 10.9% vs. Canadian 16.7 ± 19.7%, p <0.001) and proteoglycan deposition (7.9 ± 11.2% vs. Canadian 3.7 ± 5.3%, p<0.023) were significantly different. Despite the Indians having low total cholesterol, there was greater diffuse double and triple‐vessel disease and at a younger age than in the Caucasians.Conculsions: From our data, it appears that the mechanism of development of atherosclerotic disease in the Indians may be different because they have smaller vessels, smaller necrotic core, and greater proteoglycan deposition. Other etiologies, especially those related to a high carbohydrate diet (which is typical for South Indians), should be considered.
Acute coronary syndromes in the united states and united kingdom: A comparison of approaches
Authors: Adams Philip C. , Skinner Jane S. , Cohen Marc , Mcbride Ruth , Fuster Valentin ,   The Antithrombunc Therapy In Acute Coronary Syndromes Research Grow
Published: February 2009

AbstractBackground: Patients with coronary artery disease are managed differently in different countries.Hypothesis: These variations in patient management may affect clinical outcome, a possibility that should be taken into consideration in multicenter studies.Methods: In a binational, 3 months study of antithrombotic treatment of patients with unstable angina and non‐Q‐wave infarction (ATACS), we compared the experience in the four enrollment centers in the United States (US) with the three centers in the United Kingdom (UK). The 59 US patients and the 299 UK patients were similar with regard to age, rates of prior revascularization, prior positive exercise tests, medication use, and aspirin use.Results: US patients were more commonly women (45 vs. 28%), diabetic (30 vs. 4%), or hypertensive (52 vs. 31%), and had a prior coronary angiogram (30 vs. 18%). After enrollment, coronary angiography was performed more frequently in the US than in the UK (61 vs. 22%). Although the distribution of coronary disease was similar, revascularization without recurrent angina (19 vs. 4%, p<0.001), or following recurrent angina (8 vs. 3%), was significantly more frequent in the US. Combined primary end points (recurrent angina, myocardial infarction, or death) did not differ between US (29%) and UK (25%) patients.Conclusion: Therefore, international studies of acute coronary disease need to account for different treatments in different countries. These differences, in the small ATACS study, did not have a major impact on the composite primary outcome variables.
Adjunctive therapy after reperfusion therapy in acute myocardial infarction
Authors: Dries Daniel L. , Solomon Allen J. , Gersh Bernard J. 
Published: February 2009

AbstractThe current era has witnessed dramatic improvement in the treatment of acute myocardial infarction, due in large part to the more widespread use of thrombolytic therapy aimed at quickly restoring perfusion in the infarct‐related artery. This review addresses the role of adjunctive pharmacologic therapy in the thrombolytic era, recognizing that much of the available clinical trial data supporting the role of adjunctive pharmacologic treatment strategies was conducted in patient populations not widely exposed to reperfusion therapy. This review, therefore, explores the data supporting the incremental benefit of therapy with beta blockers, nitrates, angiotensin‐converting enzyme inhibitors, or magnesium in addition to thrombolytic therapy. Heparin and aspirin will not be discussed.
Evaluation of hemolysis in patients with prosthetic heart valves
Authors: Maraj Rajiv , Jacobs Larry E. , Ioli Alfred , Kotler Morris N. 
Published: February 2009

AbstractThe primary mechanism and most common cause of hemolytic disease in patients with prosthetic heart valves are mechanical trauma to red blood cells and paraprosthetic valvular regurgitation, respectively. Presenting features in patients with this condition include anemia, congestive heart failure, fatigue, jaundice, dark urine, and a regurgitant murmur. Various laboratory studies can be utilized to diagnose hemolytic anemia and to assess the severity of hemolysis. Transthoracic echocardiography, transesophageal echocardiography, and Doppler studies including color Doppler are useful imaging methods to assess valve function. Treatment is usually medical (oral iron); however, in patients with paravalvular regurgitation, surgery is often required to correct the anemia.
Inducible nitric oxide synthase and atherosclerosis
Authors: Ikeda Ulchi , Maeda Yoshikazu , Shimada Kazuyuki 
Published: February 2009

AbstractNitric oxide (NO) synthase induction in vascular smooth muscle cells may play a role in local vascular injury associated with atherosclerosis or postangioplasty restenosis by inhibiting smooth muscle cell proliferation and contraction, as well as by preventing leukocyte and platelet adhesion. The expression of inducible NO synthase is increased in balloon‐injured arteries of experimental animals or in human atherosclerotic lesions. Replacement therapy with NO donors or NO synthase gene transfer may improve the clinical course of atherosclerosis or restenosis.
Restoration of coronary blood flow by single bolus injection of the gpiib/iiia receptor antagonist c7e3 fab in a patient with acute myocardial infarction of recent onset
Authors: Domanovits Hans , Janata Karin , Laggner Anton N. , Hornykewycz Stephan , Nikfardjam Mariam , Maurer Gerald , Huber Kurt 
Published: February 2009

AbstractIt has been debated that primary coronary angioplasty could be more effective if immediate antithrombotic therapy would contribute to a faster recanalization of the infarct‐related artery. This is the first report of a patient who presented at the emergency department with acute anterolateral myocardial infarction, in whom a single bolus injection of c7E3 Fab (0.25 mg/kg body weight) led to complete reperfusion of the infarct‐related coronary artery during organization time for planned acute coronary angioplasty. Pain relief 15 min after initiation of therapy and ST‐segment resolution of >50%, as well as occurrence of idioventricular rhythm 30 min thereafter, were suggestive of successful recanalization before the coronary intervention was started. Diagnostic coronary angiography at 90 min revealed TIMI‐grade 3 flow in the infarctrelated coronary artery with only moderate luminal irregularities. Bolus administration of c7E3 Fab could be effective for dissolving platelet‐rich thrombi in the early stage of acute myocardial infarction (AMI) and may therefore represent a promising “bridging” therapy in patients with AMI elected for primary coronary angioplasty.
Relative value of clinical and transesophageal echocardiographic variables for risk stratification in patients with infective endocarditis
Authors: Lancellotti Patrizio , Soyeur Daniel , Piérard Luc A. , Galiuto Leonarda , Albert Adelin 
Published: February 2009

AbstractBackground: Infective endocarditis remains a life‐threatening disease, and its optimal management is of paramount importance. Transesophageal echocardiography (TEE) is useful for the diagnosis of endocarditis‐induced lesions, but the prognostic significance of the method remains controversial.Hypothesis: The purpose of this study was to relate clinical and TEE characteristics to the occurrence of mortality and/or systemic embolization in a consecutive series of 45 patients with a diagnosis of infective endocarditis.Methods: All patients underwent at least one monoplane TEE. Clinical data, episodes of embolization, and echocardiographic characteristics were prospectively recorded. Stepwise logistic discriminant analysis was performed to identify the independent variables that best predicted three binary outcomes: systemic embolization, death, and systemic embolization and/or death.Results: Twelve of the 45 patients (27%) died from the endocarditis. Significant univariate predictors of death were the presence of paravalvular abscess (p = 0.025), number of vegetations (p = 0.021), Staphylococcus aureus isolated in blood cultures (p = 0.002), medical treatment alone (p<0.002), and systemic embolism (p<0.001). In multivariate analysis, systemic embolism (χ2 = 29.3; p<0.01), echocardiographic evidence of paravalvular abscess (χ2 = 5.6; p = 0.018), Staphylococcus aureus endocarditis (χ2 = 5.5; p = 0.016), and medical treatment alone (χ2 = 5.11; p = 0.024) emerged as optimal predictors of death. Systemic embolization occurred in 12 patients. Independent variables predicting systemic embolization were a total length of vegetations > 14 mm (p = 0.01), greater age (p = 0.02), and medical treatment alone (p = 0.03). When two or more vegetations were observed, the total length is the sum of the individual sizes. Independent risk factors for the development of systemic emboli and/or death as a combined end point were total length of vegetations on TEE (χ2 = 6.4; p = 0.003) and medical treatment alone (χ2 = 4,1; p = 0.047).Conclusions: High‐risk patients may be identified by the combination of clinical variables and TEE characteristics.
Ischemia‐induced reflex sympathoexcitation during the recovery period after maximal treadmill exercise testing
Authors: Dilaveris Polychronis E. , Zervopoulos George A. , Michaelides Andreas P. , Sideris SKEVOS K. , Psomadaki Zoi D. , Gialafos ELIAS J. , Gialafos John E. , Toutouzas Pavlos K. 
Published: February 2009

AbstractBackground: Heart rate variability (HRV) analysis is problematic during maximal treadmill exercise testing (ET) due to rapidly changing heart rate.Hypothesis: The aim of this study was to assess HRV spectral components during treadmill ET in patients with coronary artery disease (CAD) and in healthy controls, and to search for possible differences between the two groups.Methods: Thirty patients with CAD and 30 age‐matched healthy controls underwent symptom‐limited ET and continuous electrocardiographic monitoring. For adequate assessment of HRV during maximal ET, we calculated the HRV measures [normalized units (NU)]—low‐frequency (0.040‐0.150 Hz) power (LF), high‐frequency (0.150‐0.400 Hz) power (HF), and the LF/HF ratio—from all the sequential stages of the ET with limited changes (20 beats/min) in heart rate (stress 80‐100, 100‐120, 120‐140, 140‐160, 160‐180/ recovery 180‐160, 160‐140, 140‐120, 120‐100, 100‐80).Results: Both LF and HF were found to decrease gradually during ET and to increase during the recovery period in both patients and controls (p<0.001). LF values were higher during the recovery period than during the respective stages of exercise time in both patients and controls, and LF/HF ratio was higher during recovery in patients only.Conclusions: During maximal ET (1) vagal tone withdraws during the exercise time and increases during the recovery period; (2) the sympathetic activity predominates during the recovery period, especially in patients with CAD and exercise‐induced myocardial ischemia. This finding raises the possibility of ischemia‐induced cardiocardiac sympathetic excitatory reflexes.
Potential cardiovascular applications of glutamate, aspartate, and other amino acids
Authors: Arsenian Michael 
Published: February 2009

AbstractCardioplegic solutions rich in the hydrophilic, basic amino acids, glutamate and aspartate, have enhanced myocardial preservation and left ventricular function. This has been demonstrated in assorted animal preparations involving ischemia with and without reperfusion. Published clinical data, though limited, strongly support the contention that these amino acids have myocardial protective properties. Several biochemical mechanisms exist by which certain amino acids may attenuate ischemic or reperfusion injury. Glutamate and aspartate may become preferred myocardial fuels in the setting of ischemia. They may also reduce myocardial ammonia production and reduce cytoplasmic lactate levels, thereby deinhibiting glycolysis. Some amino acids may become substrate for the citric acid cycle. Glutamate and aspartate also move reducing equivalents from cytoplasm to mitochondria where they are necessary for oxidative phosphorylation and energy generation. A rationale exists for the use of an amino acid‐rich cardioplegia‐like solution in myocardial infarction. These solutions are safe and inexpensive.
Comparison of epirubicin and doxorubicin cardiotoxicity induced by low doses: Evolution of the diastolic and systolic parameters studied by radionucide angiography
Authors: Cottin Yves , Louis Pierre , Wolf Jean Eric , Touzery Claude , Dalloz Florence , Coudert Bruno , Toubeau Michel , Riedinger Alina , Brunotte Francois 
Published: February 2009

AbstractBackground: Previous studies have demonstrated that epirubicin (EPI) has a lower propensity to produce cardiotoxic effects than doxorubicin (DXR) at high doses.Hypothesis: The aim of the study was to compare the cardiotoxicity induced by low doses of EPI and DXR in patients before and 1 month after the end of chemotherapy.Methods: In a prospective study, 99 patients with a mean age of 51 ± 12 years and without cardiac disease were studied before and 1 month after the end of chemotherapy. Group 1 included 38 patients receiving 246 ± 96 mg/m2 of DXR and Group 2 included 61 patients receiving EPI with an equivalent dose of 219 ± 92 mg/m2 of DXR. Ejection fraction (EF) of the left ventricle (LV), peak ejection rate (PER), and peak tilling rate (PFR) [expressed in end‐diastolic volume/s (EDV/s)] were evaluated by gated radionuclide angiography; PFR/PER were also calculated.Results: Moderate and similar alterations of left ventricular ejection fraction were shown for low doses of anthracyclines. The EF of the LV decreased from 57 ± 6% to 54 ± 6% for DXR group (Group 1) (p = 0.005), and from 58 ± 5% to 55 ± 5% for the EPI group (Group 2) (p = 0.001). The PER of the left ventricle fell from 3.08 ± 0.46 EDV/s to 2.79 ± 0.49 in Group 1 (p = 0.004) and from 2.98 ± 0.50 to 2.73 ± 0.34 EDV/s in Group 2 (p = O.001). In contrast, no significant alteration of PFR appeared in Group 2 (from 2.72 ± 0.51 to 2.62 ± 0.41 EDV/s) for the equivalent dose of anthracycline, while PFR of the LV dropped from 2.82 ± 0.76 (EDV/s) to 2.41 ± 0.55 after doxorubicin (p = 0.004). No difference was found between 1 and 12 months after the end of the treatment in 25 patients in Group 1 and 28 patients in Group 2. These results confirm the advantage of EPI over DXR in terms of cardiotoxicity and help explain the relationship of cellular damage mechanisms with the functional parameters of nuclear investigation.Conclusion: A possible explanation for specific alteration after DXR could be the increased production of semiquinone free radicals, which are known to induce membrane damage and, consequently, myocardial edema and diastolic alteration.
Acute myocardial infarction in two adolescent males
Authors: Duvernoy Claire S. , Bates Eric R. , Fay William P. , Farrehi Peter M. , Werns Steven W. 
Published: February 2009

AbstractAcute myocardial infarction in previously healthy children is rare in the absence of congenital anomalies. We describe two cases of acute anterior myocardial infarction in adolescent males with no congenital heart disease, without prior history of or risk factors for coronary heart disease, and with no history of drug abuse. These cases illustrate that myocardial infarction in the absence of systemic illness or coronary anomalies can occur in an adolescent population.
Doxorubicin‐induced cardiomyopathy treated with carvedilol
Authors: Fazio Serafino , Palmieri Emiliano Antonio , Ferravante Beatrice , Bon È Filomena , Biondi Bernadette 
Published: February 2009

AbstractEven today, heart failure due to doxorubicin‐induced dilated cardiomyopathy seems to have a poor prognosis, as it is often irreversible and relatively unresponsive to standard medical treatment. This paper describes the first case of a patient complaining of severe symptoms of congestive heart failure due to doxorubicin‐induced dilated cardiomyopathy unresponsive to standard medical treatment (digoxin, diuretics, and angiotensin‐converting enzyme inhibitor), who showed complete clinical recovery and significant improvement of left ventricular dysfunction after carvedilol treatment. It also illustrates the possibility that carvedilol may be a first‐choice drug for the treatment of this disease.