bluuebunny/crossref_metadata_2025_split huggingface dataset:
Effects of verapamil on left ventricular diastolic function at rest and during isometric exercise in patients with hypertrophic cardiomyopathy
Authors: Bryhn M. , Eskilsson J. 
Published: February 2009

AbstractTen patients with hypertrophic cardiomyopathy were examined with echocardiography before and during verapamil treatment to evaluate short‐term and long‐term effects of verapamil on left ventricular diastolic function. All patients were in sinus rhythm and in NYHA functional class I. Effects on filling and myocardial relaxation were documented by digitized echocardiography obtained at rest and during isometric exercise before treatment, after two weeks (short‐term) and four months (long‐term) treatment, respectively. At rest a significant decrease of the myocardial relaxation time was found during verapamil treatment. A few patients, however, returned to almost baseline conditions after an initial improvement. A small increase in the peak rate of dimension change, a parameter of filling, reached statistical significance at the end of the long‐term treatment period. Isometric exercise did not induce any changes in the diastolic parameters during verapamil treatment. A positive effect of verapamil was thus seen on both myocardial relaxation and left ventricular filling, but only in resting conditions.
Right atrial vegetation in left ventricular‐right atrial communication
Authors: Murata T. , Fujino M. , Sasaki J. , Takii M. , Arakawa K. 
Published: February 2009

AbstractWe report a case of right‐sided endocarditis with left ventricular‐right atrial communication in which right atrial vegetation was demonstrated by two‐dimensional echocardiography. The present case demonstrates that the right atrial vegetation in ventricular septal defect is suggestive of left ventricular‐right atrial communication.
Position as a variable for cardiovascular responses during exercise
Authors: Cotsamire D. L. , Sullivan M. J. , Bashore T. M. , Leier C. V. 
Published: February 2009

AbstractTwenty‐one normal young male subjects underwent resting and exercise (bicycle) radionuclide angiography in the full supine and 70$$ upright tilt positions in order to examine the effects of position on left ventricular size and performance, hemodynamics, and exercise duration. All subjects also underwent full (90$$) upright bicycle ergometry with respiratory gas analysis to establish the level of maximal exercise capacity for each. Body position significantly (p<0.05) affected resting and exercise cardiovascular parameters. End‐diastolic and endsystolic left ventricular volumes and stroke volume were larger in the supine position, both at rest and during exercise. The cardiac output at rest and during exercise were comparable for the two positions; an increase in resting and exercise heart rate in the 70$$ tilt position compensated for the reduced stroke volume of this posture. At maximal exercise, the 70$$ upright position was associated with a greater response in left ventricular ejection fraction, otherwise this parameter was not position related. Exercise capacity, in terms of duration and workload, was significantly higher in the supine (1870$$390 s) and full upright (1830$$250 s) positions than in the 70$$ tilt position (1730$$260 s). Changes in body position significantly alter parameters of ventricular, cardiovascular, and exercise performance.
Bidirectional flow in congenital ventricular septal defect: A doppler echocardiographic study
Authors: Zeevi B. , Berant M. , Blieden L. C. , Keren G. , Sherez J. , Laniado S. 
Published: February 2009

AbstractThe purpose of this study was to demonstrate the value of combined two‐dimensional and pulsed Doppler echocardiography (echo) in localizing and recording bidirectional flow in congenital ventricular septal defect. Eight children, aged 8 months to 16 years, with clinical signs of a ventricular septal defect, underwent two‐dimensional and pulsed Doppler echo study prior to cardiac catheterization. The ventricular septal defect was documented anatomically by two‐dimensional echo in all eight patients. Flow patterns in systole and diastole through the ventricular septal defect and on both sides of the defect were carefully studied. In all eight children, systolic, high velocity, pathologic, left to right flow was documented when the sampling volume was positioned on the right ventricular side of the defect. When the sampling volume was positioned inside the defect, to and fro flow, left to right in systole and right to left in diastole, was observed. In children with moderate to large defects, the diastolic flow had a peak in early diastole. Increased pressure in the right ventricle over the left ventricle during the same period was demonstrated by cardiac catheterization and coincided with the Doppler flow. The direction of flow across the defect was affected by the size of the defect and the magnitude of the net shunt. Two‐dimensional and pulsed echo Doppler were shown to be useful in demonstrating the ventricular septal defect and estimating its size and hemodynamic significance noninvasively.
Does “Physiologic” mitral valve prolapse occur with acute blood loss?
Authors: Konicek S. , Guntheroth W. G. , Cyr D. R. , Sylvester C. E. , Mack L. A. , Reichler R. J. 
Published: February 2009

AbstractIntravascular volume changes are reported to affect the clinical and echocardiographic spectrum of patients with known mitral valve prolapse syndrome (MVPS). We tested whether acute blood loss can produce MVP in normal adults. Twenty‐one subjects were studied with Doppler echocardiography before and after donating 550 ml whole blood. Two subjects demonstrated minimal (1+) prolapse postphlebotomy, but in only one echocardiographic view, and without mitral regurgitation by Doppler. Three subjects demonstrated slight, early (not late or pansystolic) mitral regurgitation after phlebotomy, but without prolapse. Left atrial dimensions decreased significantly after the blood donation but the left ventricular size was not significantly smaller. The 1+ MVP is within the range of superior systolic motion found in 35% of a normal population, free of heart disease, and without intervention. We find no evidence in our study or in the literature that pathologic degrees of MVP can be produced in normal subjects by physiologic alteration in blood volume.
The relationship of ventricular arrhythmias to the angiographically and scintigraphically estimated extent of ventricular damage late after myocardial infarction
Authors: Huikuri H. V. , Korhonen U. R. , Linnaluoto M. K. , Takkunen J. T. 
Published: February 2009

AbstractIn order to study the quantitative relationship of ventricular arrhythmias to myocardial damage and ischemia, 61 patients with a previous myocardial infarction (at least 6 months previously) were studied by 24‐hour ambulatory ECG monitoring, cardiac catheterization, and thallium‐201 scintigraphy. Thirty‐five patients (57%) had no ectopic beats or only infrequent, unifocal ones and 26 patients (43%) had complex ventricular arrhythmias. Left ventricular function was lower in the latter (p<0.05), but the number of diseased vessels did not differ in the two groups. The reduction of thallium activity in the infarct area was more marked in patients with complex arrhythmias (p<0.001). Multiple thallium defects were not more common in arrhythmia patients, however. These data support the view that complex ventricular arrhythmias are more closely related to the severity of ventricular damage than the presence of myocardial ischemia remote to the area of previous infarction.
Current review of exercise testing: applicatiOn and interpretation
Authors: Fuller T. , Movahed A. 
Published: February 2009

AbstractExercise testing has changed dramatically in scope over the past 50 years. While initially used to assess functional capacity, it is now also utilized to detect the presence and severity of coronary artery disease (CAD), to evaluate postmyocardial infarction patients at risk for future cardiac events, to screen certain asymptomatic populations for CAD, and to evaluate dysrhythmias, peripheral vascular disease, and lung disease. Dynamic exercise in continuous multistage protocols is most popularly employed because of the more easily measured workload. The safety of exercise testing, its contraindications and termination end points are summarized. The sensitivity of exercise testing ranges between 60 and 70% while specificity has been reported between 85 and 90%. Both sensitivity and specificity are enhanced through use of radionuclide exercise thallium imaging and ventricular angiography.
Continuing medical education
Authors: Kaplan Samuel , Strong W. B. 
Published: February 2009

AbstractDrug Therapy in Infants and Children with Cardiovascular Disease By A. Schneeweiss Lea and Febiger, Philadelphia (1986) 398 pages, $45.00 ISBN: 0‐8121‐1001‐3Causation of Cardiovascular Risk Factors in Children: Prospectives on Cardiovascular Risk in Early Life Edited by Gerald S. Berensen Raven Press, New York (1985) 428 pages, illustrated, $69.50 ISBN: 0‐88167‐138‐XPediatric Cardiology, Volume 6 Edited by C. Marcelletti, R. H. Anderson, A. E. Becker, A. Corno, D. di Carlo, E. Mazzera Churchill Livingstone, Inc., New York (1986) 272 pages, illustrated, $75.00 ISBN: 0443‐0319‐24
Clinical experience with urokinase in intracoronary thrombolysis
Authors: Cernigliaro C. , Sansa M. , Campi A. , Bongo A. S. , Rossi P. 
Published: February 2009

AbstractA prospective nonrandomized study of the thrombolytic efficacy and dose‐response effect of a highmolecular‐weight urokinase, administered into the coronary artery, was conducted in 63 patients with acute myocardial infarction. Urokinase was infused (up to 180 min) at rates of 2000, 4000, 6000, and 10,000 IU/min in four consecutive groups of patients within 184±70 min following onset of chest pain. Of 54 patients with complete occlusion of the infarct‐related vessel, 48 (89%) exhibited complete reperfusion. In 9 patients with incomplete occlusion, the degree of coronary stenosis was reduced with concomitant improvement in antegrade flow. The median effective dosage requirement of urokinase to reperfuse 50% of the treated patients was 180,000 IU. A relationship between the four infusion regimens and successful reperfusion was not found. The time to reperfusion, however, ranging from 42±30 to 60±41 min, appeared to be dose dependent. The reocclusion rate at follow‐up (10–14 days) was 18%. Ejection fraction improved (40±8 vs. 47±8%, p=0.002) in patients with low pretreatment values and in those treated within 2 h of the onset of symptoms. In‐hospital mortality was 9%. Hemorrhage requiring transfusion occurred in 8% of the patients. None of the patients had levels of circulating fibrinogen inferior to 100 mg/dl. We conclude that urokinase can induce timely coronary reperfusion in patients with evolving myocardial infarction, at moderate infusion rates, and with concomitant induction of an only mild systemic lytic state.
Electrophysiological studies in thyrotoxicosis with and without associated sick sinus syndrome
Authors: Talwar K. K. , Gupta V. , Kaul U. , Ahuja M. M. S. , Bhatia M. L. 
Published: February 2009

AbstractElectrophysiological studies in 13 patients with thyrotoxicosis (5 men and 8 women, aged 17 to 76 years) are reported. Five patients presented with features of sick sinus syndrome (SSS) (Group A) while the remaining 8 patients (Group B) had no detectable cardiovascular abnormality. Sinus node function (corrected sinus node recovery and sinoatrial conduction time) was abnormal in all Group A but normal in Group B patients. Intra‐atrial, atrioventricular (AV) nodal, and infranodal conduction time and effective refractory period of atrium were normal in all patients in both groups. Effective refractory period of AV node was decreased in 6 patients (3 in each group). All Group A patients received radioiodine with complete clinical remission of sick sinus state in 4 subjects. Repeat electrophysiological studies in two of these patients, 6 and 12 months after treatment, showed complete normalization of sinus node function. This is the first reported electrophysiological study documenting the occurrence of SSS in thyrotoxicosis reversed by effective antithyroid treatment. We suggest that attempts should be made to identify underlying thyrotoxicosis in all patients with SSS, especially in the older age group. Appropriate medical treatment may prevent unnecessary implantation of permanent pacemakers in such patients.
Psychological response to an acute coronary event and its effect on subsequent rehabilitation and lifestyle change
Authors: Guiry E. , Conroy R. M. , Hickey N. , Mulcahy R. 
Published: February 2009

AbstractWe assessed anxiety, depression, body image, motivation, and coping ability in 264 patients admitted with a first myocardial infarction. They were followed over 1 year to determine the relationship between psychological factors and subsequent return to work, smoking cessation, weight reduction, and adoption of a leisure exercise program. Females showed a poorer reaction to illness than did males. The better‐educated, and patients in white‐collar occupations showed less depression and expressed greater motivation. Anxiety and poor body image, however, tended to be least common in the intermediate educational and occupational group. All psychological factors predicted leisure exercise change, and all but anxiety predicted smoking cessation. Poor body image was linked with failure to reduce weight. Low expressed motivation was the only factor predicting delayed return to work.
Gap in bundle‐branch conduction elicited by programmed his bundle stimulation
Authors: Littmann L. , Tenczer J. 
Published: February 2009

AbstractThe gap phenomenon in right bundle‐branch conduction was elicited during programmed stimulation of the His bundle. Premature beats with short and long coupling intervals showed undisturbed intraventricular conduction, while the premature beat with intermediate coupling interval blocked within the right bundle branch. The electrophysiologic mechanism of “supernormal” conduction of the earliest beats was conduction delay at a proximal site within the His bundle which allowed recovery of the right bundle branch. This study shows that programmed His bundle stimulation is a valuable method in analyzing conduction characteristics of the distal atrioventricular conduction system in cases where atrioventricular nodal refractoriness would preclude this by atrial stimulation.
Usefulness of anatomic parameters derived from two‐dimensional echocardiography for estimating magnitude of left to right shunt in patients with atrial septal defect
Authors: Chen C. , Kremer P. , Schroeder E. , Rodewald G. , Bleifeld W. 
Published: February 2009

AbstractThe ability of two‐dimensional echocardiography (2DE) to quantitate the atrial septal defect size and left‐to‐right shunt magnitude was examined in 75 adult patients with simple ostium secundum atrial septal defect (ASD) with left‐to‐right shunts of 19–92% of systemic flow as determined by oximetry. The ASD was visualized in 71 of 75 (95%) patients utilizing subcostal 2DE, and the end‐systolic atrial septal defect diameters in subcostal 2DE (ASDe) were measured. The maximal diameters of ASD measured during operation (ASDop) were obtained in 45 of these patients, who then underwent surgical ASD repair. The correlation between ASDe and ASDop was high (r=0.91, p<0.001), indicating accuracy of quantitating defect size via subcostal 2DE approach. However, the correlation between the left‐to‐right shunt magnitude and ASDe was only fair (r=0.76, p<0.01). In large ASDe the shunts varied greatly, while in small ASDe the shunts increased proportionally with increasing sizes of ASD. In addition, the ratio of left‐to‐right ventricular diameter (RVD/LVD) was determined. The RVD/LVD correlated relatively well with the shunt magnitudes (r=0.83, p<0.001). Using the two new echocardiographic parameters of ASDe and RVD/LVD, a high percentage (85%) of patients with a large left‐to‐right shunt requiring surgical closure can be identified. All 43 patients with ASDe >2.0 cm and RVD/LVD >1.1 had a left‐to‐right shunt >40%. In conclusion: (1) ostium secundum atrial septal defect size can be reliably quantitated by subcostal 2DE, and (2) ASDe >2.0 cm and RVD/LVD >1.1 are highly predictive of a left‐to‐right shunt >40%.
Hemodynamic effects of intravenous diltiazem in patients with acute myocardial infarction
Authors: Ogawa H. , Yasue H. , Nakamura N. , Obata K. , Sonoda R. 
Published: February 2009

AbstractExperimentally, diltiazem has demonstrated favorable effects on acute myocardial infarction in animals. In this study, we administered diltiazem intravenously to 11 patients with acute myocardial infarction within 24 hours from the onset and examined the hemodynamic changes. Dose was 20 minutes of 0.5 mg/min and 20 minutes of 1.0 mg/min (i.e., total 30 mg). Hemodynamic results were decrease in heart rate, blood pressure (systolic, diastolic), mean arterial pressure, double product (p<0.01), and systemic vascular resistance (p<0.05). On the other hand, stroke volume index increased (p<0.01). There were no significant changes in mean pulmonary capillary wedge pressure, cardiac index, and stroke work index. Serum diltiazem concentrations during intravenous administration in our study were near the steady‐state plasma concentrations in which oral multiple‐dose administration of diltiazem 60 mg twice or thrice daily resulted in 2 to 3 days. It is concluded that diltiazem can be administered safely to patients with acute myocardial infarction in acute phase and has two favorable hemodynamic effects on acute myocardial infarction. One is decrease of afterload, as evidenced by the decrease in systemic vascular resistance and in mean arterial presure. Second is the decrease of double product as an index of myocardial oxygen consumption.
Effect of captopril on left ventricular end‐systolic pressure‐volume and stress‐shortening relations in severe cardiac failure
Authors: Lewis B. S. , Halon D. A. , Rodeanu M. E. , Merdler A. , Saggie Y. , Schneider H. , Rosenfeld T. , Hardoff R. 
Published: February 2009

AbstractThe effects of captopril on cardiovascular dynamics and left ventricular (LV) contractility were studied in 11 patients with severe congestive heart failure and very poor global LV function. Pressures were measured using a flow‐guided catheter, cardiac output by thermodilution, and LV contraction and ejection fraction by simultaneous radionuclide angiography. Ventricular loading conditions were altered by sublingual isosorbide dinitrate to facilitate construction of LV pressure‐volume and stress‐shortening curves. Captopril decreased mean arterial pressure (p<0.02) and systemic vascular resistance, while stroke and cardiac index increased in most patients. Left ventricular ejection fraction increased from 18±5 to 22±7% (p<0.05), but contractility, assessed from endsystolic pressure‐volume and end‐systolic pressure‐shortening relations, was unchanged or decreased slightly. Heart rate and double product also tended to decrease. In contrast, arteriovenous oxygen difference widened and calculated total oxygen consumption increased during captopril therapy (p<0.05). The study showed that captopril improved forward blood flow, total oxygen extraction, and LV ejection fraction following the decreased impedance to LV emptying but not at the expense of an increase in ventricular contractility. This makes captopril an attractive drug for patients with end‐stage cardiac failure and a severely damaged myocardium.
Efficacy of nisoldipine combined with beta‐adrenergic‐blocking drugs in the treatment of chronic stable angina
Authors: O'Keefe J. C. , Creamer J. E. 
Published: February 2009

AbstractA double‐blind, placebo‐controlled study was performed to assess whether a new calcium antagonist, nisoldipine, in doses of either 5 mg or 10 mg daily, in combination with beta‐adrenergic‐blocking drugs (combination therapy) was more effective than beta‐adrenergicblocking drugs alone (single therapy) in the treatment of chronic stable angina. Treatments were assessed at two‐week intervals, using exercise electrocardiography and patients' anginal diaries. A significant improvement in exercise capacity and reduction in anginal attacks occurred only during nisoldipine (10 mg daily) combination therapy compared with single therapy. Mean exercise time increased from 419±146 s (single) to 454±158 s (p<0.02) after combination therapy. Exercise time to onset of 1 mm ST‐segment depression improved from 326±145 s (single) to 331±139 s after combination therapy, although the change was not significant. Mean number of anginal attacks decreased from 21±22 (single to 15±19 (p<0.01) during combination treatment, with an associated significant reduction in glyceryl trinitrate consumption. Adverse effects during combined therapy were minor and tolerable. Thus patients limited by exertional angina despite beta‐adrenergic‐blocking drugs may obtain supplemental relief of angina and myocardial ischemia with the addition of nisoldipine in a dose of 10 mg daily.
Magnesium infusion reduces the incidence of arrhythmias in acute myocardial infarction. A double‐blind placebo‐controlled study
Authors: Rasmussen H. S. , Suenson M. , Mcnair P. , Nørregård P. , Balslev S. 
Published: February 2009

AbstractIn a double‐blind placebo‐controlled study, 130 patients with verified acute myocardial infarction were given magnesium or placebo treatment intravenously immediately upon admission to hospital. The incidence of arrhythmias requiring treatment during the initial week of hospitalization was registered. Serum magnesium concentrations were increased from 0.7 mmol/1 to 1.3 mmol/1 as a result of the magnesium infusions. This pharmacologically induced hypermagnesemia resulted in a reduction in the incidence of arrhythmias from 47 % in the placebo group to 21 % in the magnesium group (p=0.003). In the magnesium‐treated patients, increments in serum concentrations of magnesium and potassium correlated positively (r=0.47, p<0.001). It is concluded that magnesium infusion in the postinfarct period reduces the incidence of supraventricular tachyarrhythmias, and possible pathophysiological mechanisms involved are discussed.
Antiarrhythmic effects of oral indecainide in patients with ventricular tachyarrhythmias
Authors: Macina G. , Turitto G. , Stavens C. , Fontaine J. , Hariman R. , Ursell S. , El‐Sherif N. 
Published: February 2009

AbstractIn order to assess the efficacy and safety of oral indecainide in patients with serious ventricular arrhythmias we studied 11 patients with high‐grade ventricular ectopy and ventricular tachycardia (VT) which were refractory to therapy with at least one standard antiarrhythmic drug. Spontaneous arrhythmias were quantitated by 24‐h Holter monitor before and during therapy with indecainide. Spontaneous VT was sustained in 4 patients and nonsustained in 7. Ten patients underwent baseline electrophysiologic study (EPS) and VT was induced in 9. The mean ejection fraction was 25±14%. Indecainide was given orally at a dose of 211±118 mg/day. The frequency of ventricular premature beats (VPBs) was significantly (>85%) decreased in 90% of patients, while ventricular couplets frequency decreased in 78%. Spontaneous VT was abolished in 5 of 11 (45%). Sustained VT was induced in 5 of 7 (71 %) patients who underwent follow‐up EPS. The QRS duration was significantly prolonged during therapy (0.13±0.04 s) compared to control (0.10±0.02 s). The PR, QTc, and JTc intervals were not significantly changed. Indecainide was well tolerated, but 2 patients died of ventricular tachyarrhythmias while receiving the drug. Indecainide suppressed VPBs in a high percentage of patients, but was much less successful in controlling VT. Caution is necessary when using this drug because of its potential for exacerbation of arrhythmia.