bluuebunny/crossref_metadata_2025_split huggingface dataset:
Fully automated ambulatory blood pressure in the diagnosis and therapy of hypertension
Authors: Corsi V. , GermanÓ G. , Appolloni A. , Ciavarella M. , De ZORZI A. , Calcagnini G. 
Published: February 2009

AbstractTechnical characteristics of a fully automatic apparatus* for ambulatory semicontinuous blood pressure monitoring are described. Initially, we ascertained the reliability and the fidelity in the reproduction of studied events (blood pressure, heart rate, ECG). Good results were obtained, even in comparison with other methods (blood pressure semiautomatic or invasive monitoring). We then studied the results of the research on 200 hypertensive subjects. The easy applicability of this method allowed us to demonstrate blood pressure variability over a 24‐h patient period. We now can evaluate the factors contributing to blood pressure variability and the alterations contributing to the meaning of circadian rhythm. We are now able to comment on the prevalent incidence of organic or neurogenic components in single hypertensive states, the possible coexistence of asymptomatic coronary heart disease, and on the choice and efficacy of hypotensive drugs.
Simultaneous assessment of segmental and global left ventricular function by two‐dimensional echocardiography in acute myocardial infarction
Authors: Charuzi Y. , Davidson R. M. , Barrett M. J. , Beeder C , Marshall L. A. , Loh I. K. , Prause J. A. , Meerbaum S. , Corday E. 
Published: February 2009

AbstractBoth segmental and global left ventricular performance were assessed simultaneously in 29 patients with acute myocardial infarction using two‐dimensional echocardiography. Comparisons were made between left ventricular wall motion versus peak CK‐MB, site of infarction, and occurrence of heart failure. Two‐dimensional echocardiography identified areas of dyssynergy which corresponded to electrocardiographic areas of infarction in 89% of all cases. Patients with heart failure had more dyssynergic segments, and these segments manifested more severe dyssynergy than patients without heart failure. Patients with severe global dysfunction manifested higher peak CK‐MB values, and those with anterior infarction had more global dyssynergy than did those patients with inferior infarction.These observations suggest that two‐dimensional echocardiography is a useful technique for localization and assessment of segmental and global dyssynergy in acute myocardial infarction. Information so derived correlates with the clinical status of patients with acute myocardial infarction, and may offer important insights into both prognosis and treatment.
Mechanism of reduced cardiac stroke volume at high altitude
Authors: Alexander J. K. , Grover R. F. 
Published: February 2009

AbstractTwo postulates have been advanced to account for reduced stroke at high altitude: (1) diminished venous return secondary to contracted plasma volume and (2) left ventricular (LV) dysfunction secondary to hypoxia. To test these hypotheses, we assessed LV dimensions and contractility indices by M‐mode echocardiography and systolic time intervals in 11 young men at sealevel and serially for 10 days at 3100 m altitude. Mean LV end‐diastolic dimension fell 16% after 6‐8 days, with a 20% decrease in plasma volume reflected by hematocrit rise. Pre‐ejection period to LV ejection time (PEP/LVET) ratio was increased after 1‐2 days. All indices of contractility were unchanged at rest, and slightly enhanced during exercise. Thus stroke volume falls and PEP/LVET ratio rises at 3100 m because of diminished venous return despite preservation of LV systolic performance.
Ventricular tachycardia: Newer insights
Authors: Schwartz A. B. , Scheinman M. M. 
Published: February 2009

AbstractElectrophysiology has provided insights into our understanding of ventricular tachycardia. The techniques of electrophysiology which were useful as a research tool have only recently come to be appreciated in clinical practice. As a result, we have expanded our knowledge of the mechanisms of ventricular arrhythmias; we can distinguish among tachycardias masquerading as ventricular tachycardia; we can predict the response to drug and pacemaker treatment, and we can select out those who require surgical management.
The value and limitation of radionuclide angiocardiography with stress in women
Authors: Greenberg P. S. , Berge R. D. , Johnson K. D. , Ellestad M. H. , Ilijas E. , Hayes M. 
Published: February 2009

AbstractThe radionuclide angiograms (RNA) with exercise of 64 females were reviewed. There were 30 patients with coronary artery disease, 5 normal controls, 6 patients with normal coronary arteries and hemodynamics, and 23 patients with cardiomyopathy (left ventricular end‐diastolic pressure ⩾15 or ⩾18 pre‐ and postangiogram). In the coronary artery disease group, 12 of the 30 (40%) had ST‐segment depression and another 12 (40%) had a wall motion abnormality with exercise. In the cardiomyopathy group, 8 of the 23 (35%) had ST‐segment depression, and (26%) developed wall motion abnormality with exercise. In the normal coronary group, 2 of the 6 (33%) had a positive ST‐segment response, and none had a wall motion abnormality with exercise. The ejection fraction (EF) response with exercise in the normal coronary group was 65.4‐72% (p<0.02), in the coronary artery disease group 59.1‐56.2% (p<0.025), and in the cardiomyopathy group 62‐58.8% (p<0.03). If °EF⩾5 units with exercise was the normal response, then 5 of 11 (45%) normals were misclassified. If °EF>0 was a normal response, then the specificity was 10 of 11 (91%) for normals or 5 of 6 (83%) for the normal coronary group at angiography. The sensitivity for coronary artery disease was 23 of 30 (77%) and 17 of 23 (74%) for cardiomyopathy. Of the cardiomyopathy patients 3 of 4 (75%) had a positive TL‐201 scan with exercise consistent with reversible ischemia. In summary, many females with chest pain have abnormal hemodynamics despite normal coronary arteries. Use of °EF>0 as the criteria for a normal response to exercise is more specific than °EF⩾5 with exercise for separating normals from abnormals. A wall motion abnormality that develops with exercise can be seen with cardiomyopathy or with coronary artery disease in females. The radionuclide angiographic studies with exercise can separate normal from abnormal, but not cardiomyopathy from coronary artery disease. The positive TL‐201 response with exercise in the cardiomyopathy group would suggest that a regional process could be present and only cardiac catheterization can separate cardiomyopathy from coronary artery disease.
Exercise two‐dimensional echocardiography: A technique for improving ultrasound images during exercise stress
Authors: Simard M. , Heng M. K. , Udhoji V. N. , Weber L. 
Published: February 2009

AbstractA system of exercise stress echocardiography was developed in which, during exercise on a bicycle ergometer in a semirecumbent position, the echocardiographic transducer is held by a special device which maintains a relatively constant position between the transducer and the heart. The system was evaluated in 21 healthy subjects and technically satisfactory studies were obtained in 20. In these, the resolution and relative position of the cardiac image remained stable throughout exercise. Blood pressure and heart rate increased appropriately with our protocol with supine exercise; 95% of the subjects reached 90% of their predicted maximum heart rate for age. Ejection fraction measured by echocardiography increased from 54±1% to 70±1%. It is concluded that the use of our transducer‐holding device in subjects performing exercise in the supine position significantly improves ultrasonic image quality and should enhance the clinical usefulness of exercise stress echocardiography.
Report: Association of coronary artery disease and valvular heart disease in chile
Authors: Marchant E. , Pichard A. , Casanegra P. 
Published: February 2009

AbstractThis study analyzes the prevalence of coronary artery disease (CAD) among patients with rheumatic valvular heart disease (VHD) in Chile. Coronary angiography was performed in all patients referred to cardiac catheterization with VHD who were over age 50 years and who had angina or ECG signs of ischemia. A total of 100 patients entered the study. Significant CAD (greater than 50% obstruction) was found in 14% of the cases: 7% in patients with mitral valve disease (MVD), 18% in aortic valve disease (AVD), and 21% in combined mitral and aortic valve disease (MAVD). Angina was present in 14% of the patients with MVD, 63% with AVD, and 53% with MAVD. Only 57% of patients with CAD had angina pectoris; 20% with angina had CAD. Hemodynamic parameters and left ventricular ejection fraction were not correlated with the presence or absence of CAD. We conclude that in patients with valvular heart disease, the incidence of CAD is lower in Chile than previously reported in the English literature. We confirmed the fact that angina is often not associated with CAD, and that CAD is often present in the absence of angina.
Early and late morphologic changes in human coronary arteries after percutaneous transluminal coronary angioplasty
Authors: Waller B. F. 
Published: February 2009

AbstractCertain clinical and morphologic observations are described in 6 men who had percutaneous transluminal coronary angioplasty (PTCA) of the left anterior descending (LAD) or right (R) coronary artery early (4 hours to 7 days) or late (80, 90, and 150 days) before coronary endarterectomy and aortocoronary bypass grafting or death. Histologically, each of the 3 early patients had the site of PTCA narrowed 76–95% in cross‐sectional area by atherosclerotic plaque, and each had either coronary dissection or plaque hematoma or both at the site of PTCA. Each of the 3 late patients had a decrease in the mean trans‐stenotic coronary gradient (17, 38, and 43 mmHg, respectively) and an angiographic increase in the LAD luminal diameter (55, 60, and 65%, respectively) at the time of PTCA. At necropsy, 80, 90, and 150 days later, the LAD coronary artery in the area of the PTCA in each patient was narrowed 76–95% in cross‐sectional area by plaques. No cracks in plaques or other lesions which may have resulted from the PTCA procedure were identified histologically in the LAD coronary artery of any late patient.
A Double‐Blind Study of Oxprenolol Once and Twice Daily in Hypertensive Patients
Authors: Glazer N. , Friedman B. , Gerlings J. E. , Gross S. , Lowney C. , Solomon R. 
Published: February 2009

AbstractIn a randomized double‐blind study of 175 patients with mild‐to‐moderate hypertension, oxprenolol hydrochloride (160‐480 mg) given once daily was compared with the same drug given twice daily for efficacy, safety, and tolerability. Of these patients, 123 (58 receiving the once daily regimen and 65 receiving the twice daily regimen) were included in the analysis of efficacy. Both groups showed similar significant (p<0.01) reductions in mean blood pressure during the 6‐week titration period and for the remainder of the trial. A comparison of mean standing diastolic blood pressure and supine systolic and diastolic blood preses showed no significant difference between groups during the fixed dosage period. The number of patients reporting adverse experiences was not significantly different for the two regimens. Plasma triglycerides increased in both groups, but there were no other laboratory abnormalities related to treatment. This study shows that oxprenolol given once daily is effective, safe, and well tolerated in the treatment of mild‐to‐moderate hypertension.
Effect of calcium antagonists on cardiac performance in patients with dilatative cardiomyopathy evaluated by noninvasive methods
Authors: Maurer E. , Nicoletti R. , Brandt D. , Klein W. 
Published: February 2009

AbstractWe present 14 patients with dilatative cardiomyopathy, proven by hemodynamic and angiographic assessment who received in a single‐blind, randomized study, equipotent doses of the three calcium blockers: verapamil (0.1 mg/kg i.v., followed by an infusion of 0.01 mg/kg/min), nifedipin (20 mg sublingually), or diltiazem (0.2 mg/kg i.v., followed by infusion of 0.02 mg/kg/min). Before and after treatment in 8 patients systolic time intervals were recorded with an AVL‐Myocard‐Check (Q‐S2, pre‐ejection period, left ventricular ejection time, and pre‐ejection period/left ventricular ejection time) and end‐systolic and end‐diastolic diameter, fractional shortening, and circumferential fiber shortening velocity were measured by M‐mode echocardiography. In another 6 patients radionuclide ventriculography was performed before and after each treatment (ejection fraction, cardiac index). PEP/LVET increased slightly after verapamil (+15%) and decreased after nifedipin (—5%) and diltiazem (—3%), the changes being not significant. Fractional shortening and circumferential fiber shortening velocity however, decreased after verapamil (‐5%, resp. ‐15%) and increased after nifedipin (+14%, resp. +25%) and after diltiazem (+23%, resp. +16%). In the radionuclide studies ejection fraction increased after verapamil (+9%), nifedipin (+14%), and diltiazem (+13%), while cardiac index remained unchanged with verapamil and nifedipin and increased with diltiazem (+14%). In conclusion there are no significant changes in myocardial performance with the calcium blockers verapamil, nifedipin, and diltiazem. However, under verapamil there is a tendency to deterioration of myocardial performance, while it was slightly improved after nifedipin and diltiazem. Calcium antagonists may be used safely, therefore, also in patients with impaired myocardial performance.
Electrophysiological effects of quinidine alone and of the combination quinidine‐verapamil on av conduction in humans
Authors: Theisen K. , Scheininger M. 
Published: February 2009

AbstractThe influence of 320 mg quinidine administered intravenously (i.v.), as well as subsequent administration of 5 mg verapamil i.v. on atrioventricular conduction was studied in 8 patients during sinus rhythm and atrial stimulation with the aid of His bundle electrography. Among the electrophysiologic parameters of the atrium the sinus rate increased significantly after quinidine and again increased slightly after subsequent administration of verapamil. During sinus rhythm the PA interval was not influenced by either substance. Conversely, during atrial stimulation the STA interval increased significantly under the effect of quinidine, while verapamil had no further influence. As an indicator of conduction time in the AV node, the AH interval was decreased significantly by quinidine during sinus rhythm and atrial stimulation. This effect was significantly counteracted by the additional administration of verapamil. The HV interval as a measure of the His‐Purkinje conduction was not significantly affected. The QRS duration was increased significantly by quinidine and was not further influenced by verapamil. The QTCand QT intervals increased significantly after administration of quinidine and were again slightly, but significantly shortened by verapamil. Our investigations show that the combination of quinidine and verapamil, which has clinically been found to have a higher conversion rate than quinidine alone, is well justified from an electrophysiologic point of view and that undesirable quinidine‐related effects, such as rapid AV conduction in cases of atrial fibrillation and flutter, can be avoided by the subsequent administration of verapamil.
Value of treadmill exercise test in pre‐ and postoperative children with valvular aortic stenosis
Authors: Barton C. W. , Katz B. , Schork M. A. , Rosenthal A. 
Published: February 2009

AbstractTo determine the utility of graded treadmill exerise test (ETT) in estimating severity of obstruction in postoperative patients with aortic stenosis, we compared results to a nonoperated aortic stenosis group. Cardiac catheterization was performed in all patients. The interval between surgery and ETT in the postoperative group was 7.5 years (range 1.1–12.9). Mean and range values for postoperative versus nonoperative aortic stenosis groups respectively were: age 14.5 (7.9–20.8) versus 12.5 years (5.9–19.7); peak left ventricular pressure 150 (101–190) versus 144 mmHg (100–183); peak systolic ejection gradient (PSEG) 41 (15–75) versus 38 mmHg (14–80); left ventricular end‐diastolic pressure (LVEDP) 13.4 (7–20) versus 13.5 mmHg (8–20); and cardiac index 3.7 (2.4–5.6) versus 3.8 liters/min/m2 (2.6–4.9) (p for each = NS). ETT in the nonoperated patients correctly identified all those with PSEG ≥ 50 mmHg (sensitivity 100%), but specificity was 56%, (i.e., the proportion correctly identified with PSEG <50 mmHg). By contrast, sensitivity and specificity for postoperative aortic stenosis patients were 67% and 63%, respectively. Furthermore, among nonoperated aortic stenosis patients ST depression on ETT identified those with increased left ventricular end‐diastolic pressure. For LVEDP ≥ 12 mmHg, sensitivity was 75% and specificity 100%; corresponding values for postoperative aortic stenosis patients were 45% and 33%, respectively. In the nonoperated aortic stenosis group with a PSEG ≥50 mmHg, sensitivity and specificity for ETT‐induced change in systolic blood pressure of ≤30 mmHg were 100% and 56%, respectively. The data suggest that in patients with valvar aortic stenosis, ETT‐induced ST depression and systolic blood pressure change ≤30 mmHg are excellent indicators of obstruction (PSEG ≥50 mmHg) or diminished compliance (LVEDP ≥12 mmHg) in the nonoperated state but less sensitive indicators of severity in the postoperative state.
Left ventricular dysfunction in rocky mountain spotted fever
Authors: Marin‐Garcia J. 
Published: February 2009

AbstractRocky Mountain spotted fever is a serious infectious disease that continues to occur with increasing incidence in various areas of the United States. A high case‐fatality ratio (11%) persists in spite of availability of adequate chemotherapeutic agents, and the cardiac involvement may play an important role in the final outcome of some cases. To assess the effect of the disease on left ventricular function 13 patients underwent Mmode echocardiographic examination on admission to a children's hospital. Increased left ventricular dimension was found in 3 patients and decreased left ventricular shortening fraction in 9. Diminished mean velocity of circumferential fiber shortening and increased left ventricular systolic time interval ratios were found in 8 patients and increased mitral valve E point to ventricular septal separation in 9. One patient died and biventricular dilatation with diffuse myocarditis was seen at autopsy. Repeat echo examination was available in 11 patients at follow‐up (mean 5 months). Abnormal E mitral point to ventricular septal separation remained in 4 patients and decreased left ventricular shortening fraction in 2. The long‐term prognosis for this group is unknown. Myocardial involvement is frequently present in Rocky Mountain spotted fever; close monitoring and aggressive therapeutic approach are essential if the high case‐fatality ratio is to be reduced.
Continuous intracoronary nitroglycerin infusion for spasm after angioplasty
Authors: Kern K. B. , Temkin L. P. , Fenster P. E. 
Published: February 2009

AbstractA patient with reversible coronary artery spasm superimposed on fixed atherosclerotic coronary disease was treated with percutaneous transluminal angioplasty. The procedure successfully dilated the atherosclerotic lesion. However, 20 minutes later, the patient developed coronary artery spasm at the angioplasty site. Sublingual nitroglycerin, sublingual nifedipine, intravenous nitroglycerin, and repeated boluses of intracoronary nitroglycerin alleviated episodes of spasm, but failed to prevent recurrence. The patient was successfully treated with a continuous intracoronary infusion of nitroglycerin. Patients with coronary artery spasm in addition to fixed obstructive coronary disease may be at higher risk for spasm after percutaneous transluminal angioplasty. Continuous intracoronary infusion of nitroglycerin may be an effective therapy for recurrent coronary artery spasm occurring in the catheterization laboratory.
Acute massive (pericardial effusive) pulmonary thromboembolism‐pulmonary embolectomy revisited
Authors: Stang J. M. , Vanaman M. E. , Magorien R. D. , Wooley C. F. , Ruff P. D. , Mcenany M. T. 
Published: February 2009

AbstractThe most recent patient in a 13‐year experience with 14 patients suffering massive pulmonary thromboembolism requiring pulmonary thromboembolectomy is the focus of this report. This 40‐year‐old woman not only survived life‐threatening acute hypoxemia and right heart failure, but was also found to have developed a unique transudative 700 cc pericardial effusion. Pulmonary artery pressure was 90/30 (mean 50 mmHg), accompanied by 17 mm right ventricular alternans. Systemic alternans and tamponade physiology were absent. This unusual natural model for acute right heart failure illustrates a novel mechanism for pericardial effusion physiology.
Mitral annular calcification and coarctation of aorta
Authors: Nair C. K. , Ahmed I. , Sketch M. H. 
Published: February 2009

AbstractAlthough coarctation of the aorta is associated with various cardiac abnormalities, its association with mitral annular calcification (MAC) is not reported. We therefore report a 37‐year‐old patient with postductal coarctation of the aorta and MAC. Considered to be a degenerative process, MAC is usually seen in elderly patients. It is uncommon in patients less than 50 years old and rare before the age of 40 years. Previous studies have reported increased frequency of cardiac conduction disturbances in patients with MAC compared to age‐ and sex‐matched controls. This is in agreement with complete right bundle‐branch block noted on the electrocardiogram of our patient. Clinicopathologic correlative studies and long‐term follow‐up may determine how such conduction distrubances develop and progress.
Intravenous Labetalol for the Control of Hypertension Following Repair of Coarctation of the Aorta
Authors: Bojar R. M. , Weiner B. , Cleveland R. J. 
Published: February 2009

AbstractParadoxical hypertension is a relatively common complication of surgical repair of coarctation of the aorta. An early phase of systolic hypertension has been ascribed to elevated levels of norepinephrine. Activation of the renin‐angiotensin system from sympathetic stimulation has been implicated in a later phase of systolic and diastolic hypertension that can result in mesenteric arteritis. The use of a rapidly acting, titratable intravenous alpha‐ and beta‐adrenergic blocker, such as labetalol hydrochloride, addresses both of these neurohormonal mechanisms. in the intravenous form, it would appear to be an excellent choice for the management of early postoperative hypertension and it can be converted to the oral form in cases of persistent hypertension. We report for the first time the use of labetalol in two young patients for the control of paradoxical hypertension following coarctation repair.