bluuebunny/crossref_metadata_2025_split huggingface dataset:
Quantitative Coronary Arteriography and Its Assessment of Atherosclerosis
Authors: Fleming Richard M. , Harrington Gordon M. 
Published: July 2008

Background. Assessment of coronary artery disease by quantitative coronary arteriog raphy (QCA), while highly accurate, is more expensive than visual estimates of disease and involves the measurement of numerous variables requiring specialized equipment and personnel, thereby reducing its clinical applicability. In part 1 of this paper, the indepen dent variables that influence flow of 1040 coronary artery segments were analyzed. Methods and Results. Using the information previously reported in part 1 of this paper, we set out to determine the importance of each of the independent variables (percent diameter and area stenosis, length, absolute diameter, entry and exit angles) in the prediction of stenosis flow reserve (SFR). Analysis of variance (ANOVA) was used to determine the importance of each of these variables, as well as their interactions, on the determination of SFR. Only percent diameter stenosis (%DS) demonstrated statis tical significance (P < 0.001) in determining stenosis flow reserve. When the results of SFR were plotted against %DS, a quadratic relationship was demonstrated with an R2 value of 0.903 (r = 0.95). To verify the quadratic equation, the %DS of 100 different arterial stenoses was measured and used to calculate an SFR by the quadratic formula. The QCA and quadratic (calculated) determined SFRs compared favorably, with a correlation of 0.97. (continued on next page) Conclusions. The ability to calculate SFR directly from measured %DS allows the incor poration of calculated SFR into the clinical setting, where cardiologists can interpret lesion severity both anatomically and hemodynamically. This incorporation can be done without additional cost to the physician, hospital, patient, or third-party payers. ABSTRACT Contemporary quantitative coronary arteriography (QCA) methods accurately measure stenosis flow reserve (SFR) under conditions of coronary artery disease but are too expensive for practical clinical use. A simple laminar flow (Poiseuille) model was fitted to 1040 stenotic lesions and cross-validated on an independent sample of 100 lesions. This simple model was found adequate for practical use with a cross-validated correlation of 0.97 with QCA measurement. Turbulence and other known complexities had no practical effect.
The Potential Impact of the Thrombolytic Era on Cardiac Rupture Complicating Acute Myocardial Infarction
Authors: Salem Bakr I. , Lagos Julio A. , Haikal Maged , Gowda Siddhesh 
Published: July 2008

Cardiac rupture complicating acute myocardial infarction (AMI) remains a serious diag nostic and therapeutic challenge. The authors present 27 consecutive patients who died from cardiac rupture following AMI. These included 22 patients from 1975 through 1983 (prethrombolytic era) and 5 patients from 1984 through 1992 (postthrombolytic era) and all had postmortem examination. There were 16 men and 11 women with a mean age of seventy-two years. Myocardial infarction was anterior/anterolateral in 10 and inferior/inferoposterior in 17. Cardiac rupture followed AMI within one day in 14 (52%), two to five days in 8 (30%), and six to fourteen days in 5 (18%). Chest pain followed by sudden hypotension leading to electromechanical dissociation was the common terminal event. Cardiopulmonary resus citation was unsuccessful in all patients. Postmortem findings showed three-vessel coronary disease in 21 (78%) and two-vessel disease in 6 (22%). Isolated free left ventric ular wall rupture was found in 22 (81%), was anterior/anterolateral in 13 (48%), posterior in 9 (33%), and in conjunction with interventricular septum or papillary muscle in 5 (18%). Patients encountered in this series were mostly elderly hypertensives with multivessel coronary disease and postinfarction angina. Furthermore, cardiac rupture commonly occurred within the first five days of AMI and cardiopulmonary resuscitation was uniformly unsuccessful. During the thrombolytic era at their institution, this complication is now being seen much less often. These observations suggest that such interventions are expected to have a favorable impact on reducing the incidence of this catastrophic event.
Hypertension and Ischemic Heart Disease Role of Dipyridamole Echocardiography Test
Authors: Gulizia Michele M. , Lo Giudice Pietro , Doria Giuseppe , Valenti Rosalba , Circo Antonio G. 
Published: July 2008

The aim of this study is to try to evaluate the relationship between arterial hypertension and ischemic heart disease (IHD) in the light of the physiopathologic response pattern to the dipyridamole echocardiography test (DET) in hypertensive patients, in pharmaco logic washout, without any electrocardiographic ST segment depression during exercise tests or at rest. Sixty patients affected by mild to moderate asymptomatic essential arterial hypertension were studied: the subjects had a sitting diastolic blood pressure ≥95 ≤ 114 mmHg; there were 38 men and 22 women with a mean age of 49.8 ± 7.6 years (range twenty-nine to sixty-eight). All patients had undergone high-dose DET (0.84 mg/kg in ten minutes). No patients developed side effects or asynergy in cardiac contractility during the test. In the absence of any significant coronary artery obstruction assessed angio graphically, 18 patients (30%) showed ST segment depression > 1.0 mV during DET, sometimes with the presence of ventricular and/or supraventricular extrasystoles. In this group of patients the left ventricular mass index (LVMI) and duration of hypertension (in (continued on next page) months) were higher as compared with those of the other 42 patients (respectively: 160.2 ±5.1 vs 129.2 ±9.2 g/m2, P < 0.02; and 30 ±4.8 vs 9 ±5.4 months, P < 0.007). In conclusion it is reasonable to speculate from these data that the ischemic-like" dipyridamole-induced ST segment depression, like that shown by patients affected by Syndrome X, might involve a worse prognosis in hypertensive patients. This may be because of increased coronary resistance due to structural modification or anatomic background.
Pheochromocytoma with Echocardiographic Features of Obstructive Hypertrophic Cardiomyopathy
Authors: Balthazar Jacob José Luiz , da Silveira Luiz Carlos , de Freitas Claudia Giovanna , Pereira Cêntola Crescêncio Alberto , Nicolau Jose Carlos , Menezes Lorga Adalberto 
Published: July 2008

The authors report a case of pheochromocytoma in which the echocardiographic features suggested obstructive hypertrophic cardiomyopathy. The angiographic study and the computed tomography showed the tumor and its arterial supply. One month after resection of the tumor the echocardiographic features showed a tendency to normalization. The preoperative echocardiographic aspect was probably due to excessive produc tion of catecholamines by the tumor. José Luiz Balthazar Jacob, M.D.
Measurements of Human Coronary Vascular Impedance
Authors: Chauhan Anoop , Potter Charles D. , Mullins Paul A. , Wheeldon Derek R. , Petch Michael C. , Schofield Peter M. 
Published: July 2008

The aim of this study was to develop a method of measuring human coronary circulation impedance in a clinical setting. The authors measured coronary flow reserve (CFR) in 27 patients with chest pain and normal coronary arteries. A Judkins-style, 8F Doppler-tipped angiographic catheter was positioned in the left coronary ostium. Resting coronary flow velocity (RFV) and response to a hyperemic 12 mg intracoronary dose of papaverine (PFV) were measured. The signals were recorded by a recorder connected to a micro processor with analogue-to-digital converter and a maths coprocessor. Using this the authors could obtain values for impedance at RFV (IR) and at PFV (IP). The CFR was defined as the ratio: PFV/RFV An impedance index (II) was obtained as the ratio of coronary vascular impedance at peak hyperemia to the impedance at rest. The CFR was 3.2 ±1.2 and the II was 0.33 ±0.11. There was a strong inverse correlation between the CFR and the II (r = -0.9). The authors conclude that this new approach may allow a further insight into the coronary pathophysiology and may become useful in clinical cardiology, eg, in the assess ment of heart transplant and Syndrome X patients.
Inferior Vena Caval Thrombosis Associated with Acute Pancreatitis: An Unusual Vascular Complication—Its Presentation and Management
Authors: Antony Suresh J. , Loomis Terri , Brumble Lisa , Hannis Mark D. 
Published: July 2008

Vascular thrombosis and systemic hypercoagulable states are known complications of acute pancreatitis. They are thought to be secondary to the release of proteolytic enzymes of the pancreas. Inferior vena caval thrombosis is an extremely rare complication of chronic pancreatitis and has, to the authors' knowledge, never been reported in acute pancreatitis. The clinical presentation and radiographic findings are reviewed to illustrate the disease spectrum. Early treatment with intravenous heparin appears to be an effective therapy. Familiarity with this complication will aid physicians in its early diagnosis. However, a high degree of suspicion for this complication is necessary to make a diagnosis.
Prevalence of Infection from Subclavian Dialysis Catheters with Two Different Postinsertion Catheter Cares: A Randomized Comparative Study
Authors: Huraib Sameer , Askar Akram , Abu-Aisha Hassan , Al-Wakeel Jamal 
Published: July 2008

A comparison of the outcome of two different protocols concerning the postinsertion catheter care are reported and the literature of the subject is reviewed. Forty patients had the "Quinton" double-lumen catheter in the subclavian vein for hemodialysis. These catheters were kept in place for a total of 1392 days. The patients were divided randomly into two groups (A and B), each consisting of 20 patients. The care of group A catheters was done by the hospital intravenous (IV) team using heparin flushing three times/day The care of group B catheters was done by dialysis nurses using heparin 1 mL of 2500 units in each lumen only after dialysis, ie, three times/week. The bacteremia rate of group A was 15% while that of group B was 5%. In conclusion, flushing the catheter with heparin 1 mL/2500 units in each lumen of the catheter at the end of dialysis, ie, three times/week along with changing the dressing once per week were found valuable in decreasing the rate of bacteremia from catheter infection.
Determinants of Left Ventricular Function Two Weeks and One Year After an Acute Myocardial Infarction
Authors: Brzostek Tomasz , Van de Werf Frans , Scheys Ilse , Mortelmans Luc , Aubert André , Dubiel Jacek S. , De Geest Hilaire 
Published: July 2008

This study examines possible covariates of left ventricular function two weeks and sixteen months after an acute infarction. It was performed in a group of 312 patients randomized double blindly to recombinant tissue plasminogen activator (rt-PA) (n=156) or placebo treatment and followed thereafter for at least one year. Two weeks after the infarction, enzymatic infarct size, infarct-related vessel, and number of diseased coronary arteries were significant determinants of the infarct-related regional wall motion (centerline method) (R2=0.25 to 0.60, P=0.0001). Enzymatic infarct size, regional wall motion of both infarct-related and remote areas, reinfarction, and treatment allocation were significant independent correlates of ejection fraction (R2=0.76), end-diastolic volume (R2 =0.20), and end-systolic volume (R2=0.69, P < 0.0001). Infarct-related coronary artery and predischarge end-systolic volume were significant independent covariates of ejection fraction at rest (R2=0.47) after sixteen months. Age, enzymatic infarct size, and predischarge end-diastolic volume were independent determinants of the maximal (R2=0.49, P < 0.0001) and peak exercise ejection fraction (R2=0.49, P < 0.0001).
Doppler Ultrasound in the Diagnosis of Venous Thrombosis
Authors: Markel Arie , Weich Yehuda , Gaitini Diana 
Published: July 2008

Deep vein thrombosis (DVT) has known morbidity and mortality. New noninvasive techniques such as B-mode scanning and Doppler ultrasonography (duplex) are highly accurate in the diagnosis of this problem but are relatively expensive and time consuming. Continuous-wave Doppler, a precursor noninvasive technique, is simple, cheap, and easy to perform at the patient's bedside. To test the effectiveness of this technique the authors prospectively studied patients with clinical suspicion of DVT by Doppler ultrasound and compared the results with those from venography. During fourteen consecutive months, patients with a clinical suspicion of DVT underwent continuous-wave Doppler examination of both inferior limbs. Each case was diagnosed as positive, negative, or inconclusive. In addition, the patients underwent a questionnaire regarding risk factors, symptoms, and mean relevant physical findings. Doppler examination was blinded to venography results. A total of 116 patients with clinical suspicion of DVT were examined by Doppler ultrasound. Their mean age was fifty-five years (range: eighteen to eighty-eight). There were 57 men and 59 women, and from this group a total of 40 patients underwent both Doppler ultrasound examination and venography in the course of forty-eight consecutive hours. When cases with an inconclusive result were excluded, Doppler ultrasound showed a sensitivity of 89%, a specificity of 100%, and an accuracy of 94% for the diagnosis of DVT when compared with venography. When a similar analysis was done for the proximal named veins, continuous-wave Doppler examination showed a very high specificity and positive predictive value and a moderate sensitivity and negative predictive value. (continued on next page) In the entire group of patients with a Doppler ultrasound examination (n=116), 48 cases had a positive study. Prolonged bed rest, previous surgery, and previous DVT were the most frequent risk factors, pain and swelling the most frequent symptoms, and edema and tenderness the main clinical signs. In patients without DVT (n=57), trauma, malignant obstructing tumors, and cellulitis were the most frequent final diagnoses. The study was inconclusive in 11 patients. In conclusion, continuous-wave Doppler is accurate and may be used as the initial technique in the diagnosis of DVT. Cases that are inconclusive, or cases in which clinical findings are in evident contradiction to Doppler findings, should undergo duplex examination or venography.
Enhanced Migratory Activity of Vascular Smooth Muscle Cells with High Expression of Platelet-Derived Growth Factor A and B
Authors: Köster Ralf , Windstetter Ulrich , Überfuhr Peter , Baumann Günther , Nikol Sigrid , Höfling Berthold 
Published: July 2008

Proliferation and migration of vascular smooth muscle cells (SMCs) are major events in atherogenesis. It is known that platelet-derived growth factor (PDGF) stimulates both of these processes in a paracrine fashion, whereas autocrine stimulation has been shown only for proliferation. The aim of this study was to investigate the influence of PDGF expression in SMCs on migratory activity of these cells. SMCs were cultivated from the vascular tissue of 23 patients. Cellular motility was analyzed by a computer-assisted motion analysis system; 54 images per sample, obtained during an observation period of eighteen hours, were analyzed. PDGF-A and PDGF-B mRNA levels were determined by quantitative polymerase chain reaction (PCR) following reverse transcription. To quan titate mRNA content of SMCs, the authors coamplified cDNA copies of mRNA from cells and from a synthetic reference RNA in the same reaction vessel. Cells derived from ather osclerotic lesions produced a 1.6-fold increase of PDGF-A (P < 0.05) and a 5-fold increase of PDGF-B mRNA (P < 0.05) as compared with those from normal vessels. The migratory velocity (range 11.1-49.2 μm/hr) was independent of PDGF-A and PDGF-B mRNA expression. A significant correlation between levels of PDGF-A mRNA and PDGF-B mRNA and the degree of directional changes of SMCs on the covered track (klinokinesis) was found (P < 0.05). Conclusion: PDGF-A and PDGF-B mRNA expression is significantly correlated with positive klinokinesis without affecting migratory velocity. This finding reflects enhanced migratory activity of SMCs. Besides its known mitogenic effects, the authors present evidence that PDGF may act as an autocrine motogen* in SMCs.
Ankle/Arm Pressure Index in Asymptomatic Middle-Aged Males: An Independent Predictor of Ten-Year Coronary Heart Disease Mortality
Authors: Kornitzer M. , Dramaix M. , Sobolski J. , Degre S. , De Backer G. 
Published: July 2008

Purpose of the study: to evaluate the predictive power of a reduced ankle/brachial pressure index (ABPI) (≤ .90) in an asymptomatic middle-aged male working population free of coronary heart disease. Materials and Methods: 2023 subjects forty to fifty-five years old were screened at their work place. Standard techniques were used. Blood was drawn in the fasting state. Ankle and brachial blood pressures were measured by Doppler signals and all measures were done by one observer, duly trained in epidemiologic methodology Results: in univariate analysis, an ABPI ≤ .90 was significantly associated with age, total serum cholesterol, body mass index, smoking, and awareness of diabetes. In multi- variate analysis, it was associated with awareness of diabetes, age, Ln triglycerides (P=.073), and smoking (P=.088). Relative risks for reduced versus normal ABPI are 2.77 (P=.010), 4.16 (P=.011) and 4.97 (P=.006) for ten-year all causes, cardiovascular, and coronary mortality, respec tively. In a multiple logistic regression analysis, the following variables were significant independent predictors of coronary mortality: smoking (odds ratio [OR] =4.84), reduced ABPI (OR=3.63), and low density lipoprotein cholesterol (OR for 1 SD=1.69). Reduced ABPI is also an independent predictor of cardiovascular mortality Conclusion: a reduced ABPI is an independent risk factor for coronary and cardio vascular mortality in asymptomatic middle-aged Belgian males.
Short-Term Evaluation of Plaque Area Measurement Reproducibility from Computer-Assisted Sonography
Authors: Massonneau M. , Caillard Ph. , de Chassey L. , Mouren X. , Thebault B. , Cloarec M. 
Published: July 2008

One reason why quantifying plaque regression is difficult is the poor spatial control of the shooting angle whether in angiography or ultrasonography techniques. A computer-assisted technique has been developed to assess absolute carotid plaque dimensions from B-mode ultrasonography, with enhanced capability of comparative examinations at large time intervals. Plaque area is measured from arterial lumen to adventitia with a real-time tissular detection program. Further measurements on the same patient are made using an echo-specific mask automatically generated by the computer from the original section. For an average sonographer, the manipulation takes no more than ten minutes for each view. In order to determine the reproducibility of this technique, a repeated measurement study (TO, T1, T2) was carried out on 8 patients with moderate to severe atherosclerotic lesions at carotid localizations. The plaque areas ranged from 52.7 to 202.3 mm2 (120.7 ±61). The coefficients of correlation between the measurements (T0-T1, T0-T2) were respectively 0.93 and 0.96 (P < 0.0001). The mean coefficient of variation (±SD) was 9.8% ±4.8. This study shows the feasibility of an accurate follow-up for atherosclerotic patients, with a two-dimensional plaque quantification, closer to the reality of the evolution of the pathology than the usual scoring system.
Combined Left Ventricular Wall Motion and Myocardial Perfusion Stress Imaging in the Initial Assessment of Patients with a Recent Uncomplicated Myocardial Infarction
Authors: Flamen Patrick , Dendale Paul , Bossuyt Axel , Franken Philippe R. 
Published: July 2008

The aim of the study was to examine the ability to simultaneously assess left ventricular function and myocardial perfusion by using a single injection of technetium-99m Sestamibi at rest and during submaximal exercise to identify high-risk patients with left main, proximal left anterior descending (LAD), or three-vessel coronary artery disease (CAD) after an uncomplicated acute myocardial infarction (AMI). Multiple studies have evaluated the separate value of the exercise ECG, myocardial perfusion scintigraphy, and radionuclide angiocardiography (RNA) for identifying patients with severe CAD. The availability of technetium-99m (Tc99m)-labeled myocardial imaging agents offers the opportunity to evaluate simultaneously ventricular function and myocardial perfusion during a single exercise session. Only limited data are available about the value of this combined technique in the workout of patients early after an uncomplicated AMI. Combined first-pass RNA and myocardial perfusion tomoscintigraphy (SPECT) at rest and during submaximal exercise were performed in 52 patients, less than six weeks after an uncomplicated AMI, with use of Tc99m Sestamibi. Patients were classified in two subgroups according to the presence of left main, proximal LAD, or three-vessel CAD. Stepwise logistic regression analysis was used to determine the independent predictors of severe CAD. All patients underwent the exercise testing without any medical complica tion. On univariate analysis, the global left ventricular ejection fraction (LVEF), wall motion score, and myocardial perfusion score, both at rest and at submaximal exercise, were significantly associated with the presence of severe CAD. The response of LVEF to exercise, and the presence of exercise-induced wall motion or myocardial perfusion abnormalities, were not associated with the severity of CAD. On multivariant analysis only the wall motion score during exercise was an inde pendent predictor for the presence of severe CAD (P < 0.001, r=0.6). In analyzing patients with anterior AMI separately, LVEF at submaximal exercise was the most accurate predictive parameter. If a cutoff value of 40% was chosen, the LVEF at exercise had a sensitivity of 85% and a specificity of 78% for the detection of severe CAD. In patients with inferior AMI, neither LVEF nor wall motion or myocardial perfusion scores were useful for differentiating the two subgroups. In these patients the presence of an additional perfusion defect during exercise in one of the anterior wall segments yielded a sensitivity of 70% and a specificity of 75% for the presence of severe CAD. In conclusion: simultaneous evaluation of LV function and myocardial perfusion at submaximal exercise, using a single injection of Tc99m-Sestamibi, is a safe and accurate technique for selecting patients with severe CAD after an uncomplicated AMI.