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Bjurstedt H - - 1980
We studied the respiratory and circulatory effects in six healthy supine volunteers of continuous negative-pressure breathing (CNPB) at -15 and -30 cmH2O at rest and during dynamic leg exercies at 50% of individual working capacity. CNPB had no significant effects on respiratory minute volume, tidal volume, or arterial carbon dioxide ...
Benge W - - 1980
Normal or near-normal exercise capacity has been thought to reflect normal left ventricular function. Many compensatory mechanisms could preserve exercise capacity in patients with severe left ventricular dysfunction. We evaluated exercise capacity using a treadmill exercise test in 26 patients with severe left ventricular dysfunction defined by a left ventricular ...
Alpert B S - - 1980
Exercise, a physiologic stress, has been used in adults to unmask abnormalities of left ventricular hemodynamics not detectable at rest. Similar data in children are not available. An evaluation was made of the feasibility, safety and value of a graded upright and supine ergometer stress test to assess exercise hemodynamics ...
Mokotoff D M - - 1980
To determine the clinical status, the occurrence of chronic ambulatory arrhythmias, and the prognosis of patients with exercise-induced ventricular tachycardia, 26 patients with ventricular tachycardia during or immediately following exercise on a treadmill were evaluated. Of the 26 patients, 16 had coronary arterial disease, two had nonischemic cardiomyopathy, and eight ...
Francis C K - - 1980
The effect of symptom-limited maximal treadmill exercise was evaluated in 34 patients with sickle cell trait (SCT) and 43 controls. Systolic time intervals were measured before and after exercise in 15 of the sickle cell trait subjects, and in 11 controls. Rate pressure product, degree of ST segment depression and ...
DeBacker G - - 1980
Effective future research on the significance of ventricular premature beats (VPB) and their therapeutic suppression require improved and simpler methods for arrhythmia detection, characterization, and measurement. This study considers the comparative yield, repeatability, and validity of several methods of VPB detection and induction in a sample of the general population ...
Winkler R B - - 1980
Twenty-five children and young adults with complete heart block and 50 normal control subjects were maximally exercised on a treadmill and their electrocardiograms were analyzed for the presence and degree of ventricular ectopy activity. Sixty-eight % (17 of 25) of the heart block patients and significant ventricular ectopy (frequent unifocal ...
Carlens P - - 1979
The successive deterioration of left ventricular pump function during exercise-induced angina pectoris was studied in 20 candidates for aortocoronary bypass surgery. Left ventricular stroke work and power were calculated from continuous left ventricular pressure recordings and repeated measurements of cardiac output every 30 sec using the thermodilution technique. The average ...
Lehrman K L - - 1979
The effect of coronary arterial bypass surgery on exercise-induced ventricular arrhythmias and their relation to sudden death was examined in 102 patients with stable angina pectoris randomly assigned to medical and surgical therapy (54 and 48 patients, respectively). Symptom-limited treadmill tests were performed at entry and at 1 and 5 ...
Rubin S A - - 1979
Changes in left ventricular performance were evaluated in 14 patients with functional New York Heart Association class III or IV chronic heart failure before and after the addition of oral hydralazine to conventional therapy. With conventional therapy, cardiac output increased from 3.4 +/- 0.8 (mean +/- 1 standard deviation) at ...
Paulsen W J - - 1979
The effects of supine isometric handgrip and graded isotonic bicycle ergometer exercise on left ventricular performance were studied echocardiographically in 20 normal subjects, aged 18 to 36. Measurements of the left ventricular minor axis diameter were taken from recordings performed at rest, during each form of exercise, and during recovery. ...
Amon K W - - 1979
A simple technique for obtaining high-quality echocardiograms of the left ventricle during upright bicycle exercise is described. The use of this method has resulted in left ventricular dimension data that are consistent with the results of studies in conscious, previously instrumented dogs during running. Careful subject selection is important, however, ...
Dawson A K - - 1979
The risk of instantaneous death due to ventricular fibrillation was compared in resting and exercised dogs. Three weeks before testing, all dogs had bipolar left ventricular stimulating electrodes implanted and a reversible snare was placed around the anterior descending coronary artery. The dogs were randomly assigned to either an exercise ...
Goldstein R E - - 1979
Changes in left ventricular size may be of importance in the development of angina and in its amelioration by glyceryl trinitrate, but left ventricular dimensions have not been measured during exercise in the upright position, the circumstance in which angina most often occurs. To assess changes in left ventricular end-systolic ...
Cahill N S - - 1979
Left ventricle dimensions and wall stress were measured echocardiographically before and immediately after exercise in 14 athletes and 7 control subjects. Our findings suggest that afterload is an important determinant of cardiac performance and wall hypertrophy in athletes. In spite of major changes in heart rate and blood pressure, left ...
Liang C - - 1979
We studied the conditioning effects of chronic infusion of dobutamine and exercise training in three groups of chronically instrumented dogs. One group was infused with normal saline, a second group was infused with dobutamine (40 mug/kg per min), and the third group was exercised on a treadmill at 4 mph, ...
Viitasalo M T - - 1979
The occurrence of ventricular arrhythmias during exercise testing, jogging, and sedentary life with and without preceding exercise was studied with the aid of ambulatory electrocardiographic monitoring in healthy physically active men, healthy sedentary men, and men with previous myocardial infarction (15 men in each group). Ventricular premature beats of the ...
Bruce R A - - 1979
Noninvasive measurements of maximal oxygen intake and invasive measurement of systemic and pulmonary arterial pressures, arterial and mixed venous oxygen contents and direct Fick cardiac output are reported for 3 healthy men and 14 men with coronary heart disease. Observations were obtained at supine and sitting rest, during graded levels ...
Wolfe L A - - 1979
Echocardiography was employed to measure the serial effects of jogging on resting left ventricular dimensions and function. Twelve men were exercised (mean age 36.8 yr) and 10 served as controls (mean age 34.8 yr). Increases of 14 and 18% were observed for predicted aerobic capacity in the training group (TG) ...
Antman E - - 1979
Exercise stress testing is being increasingly used to verify exercise-induced arrhythmia and to aid in assessing antiarrhythmic drug efficacy. The true prevalence of ventricular arrhythmia during exercise testing is underestimated by means other than continuous monitoring. We compared the yield of ventricular premature beats (VPBs) between a continuous recording system ...
Sonnhag C - - 1979
Ten patients with persistent ventricular arrhythmia were studied in a comparison of the antiarrhythmic efficacy of N-acetylprocainamide (NAPA) and procainamide (PA). Each patient performed three exercise tests for 40 min., on different days, with submaximal and fixed work loads. During the first exercise test no drug was administered. During the ...
DeBacker G - - 1979
The influence of a 6-week intervention on factors thought to be related to ectopic cardiac rhythms was tested in normal men with frequent ventricular premature contractions (VPCs), using a randomized, controlled and partial crossover design. The VPC intervention trial experimental regimen included total abstinence from caffeine and smoking, reduction of ...
Hirota Y - - 1979
The hemodynamic effects of daily treadmill exercise were evaluated in hamsters with experimental thiamine deficiency to test the hypothesis that increased energy consumption might be a contributory factor in the pathogenesis of beriberi heart disease. Daily exercise enhanced thiamine deficiency and was manifested by earlier development of symptoms of neuropathy ...
Katkov V E - - 1979
Five healthy male volunteers were subjected to graded exercise tests on a bicycle ergometer (600 kpm/min for 8 minutes) with simultaneous catheterization of the right cardiac ventricle and radial artery, first before immobilization and them after five-day bed rest in the head-down posture (the foot bed end was elevated 4.5 ...
Kesteloot H - - 1979
Moxaprindine, a new anti-arrhythmic drug, with characteristics similar to aprindine, has been demonstrated to be highly effective in suppressing ventricular arrhythmias occurring before, during and after maximal exercise stress testing. This effect was obtained both in subjects with clinically normal hearts and in a limited number of patients with ischemic ...
Boudoulas H - - 1979
Twenty-four hour outpatient monitoring was compared with maximum multi-stage Treadmill exercise testing for the detection of dysrhythmias producing syncope or near syncope in 119 patients. All patients had cardiovascular disorders; only 21% had coronary artery disease. Patients with obvious cause of syncope and/or significant dysrhythmias by resting electrocardiograms (ECGs) were ...
Gollan F - - 1978
Current systolic time interval techniques have limited clinical applicability since patient co-operation and attention to the carotid pulse and phonocardiogram transducers are required. Therefore only surface electrodes were used to monitor the electrocardiogram and electrical impedance cardiogram first derivative (dZ/dt) in the acquisition of the timing signals. dZ/dt motion artefacts ...
Cocco G - - 1978
Lorcainide is a promising antiarrhythmic agent that belongs to the class of local anesthetics. It was tested in 7 patients with malignant ventricular arrhythmias that were resistant to other antiarrhythmic agents. Lorcainide was effective in all cases (complete disappearance of arrhythmias in 6 cases and more than 50% disappearance in ...
Swedberg K - - 1978
Tocainide is a new antiarrhythmic drug with a chemical structure related to that of lidocaine. In the present study, healthy volunteers were investigated after infusion of tocainide 450 mg over 45 min. In nine subjects His bundle electrograms, sinus recovery time and ventricular effective refractory periods were recorded. No major ...
Vecht R J - - 1978
Blood was collected simultaneously from the left ventricle and pulmonary artery in 12 patients undergoing routine cardiac catheterisation and was analysed for noradrenaline concentrations at rest, during, and after isometric stress (hand grip). Moderate isometric exercise resulted in a significant rise in plasma noradrenaline with a return to basal values ...
Talbot S - - 1978
Although ventricular tachycardia is a well-known complication of myocardial ischaemia and may be provoked by exercise, many patients may appreciate only the angina and be unaware of the unduly rapid heart rate that precipitates it. Exercise testing is needed to show this arrhythmia and to enable treatment to be started.Twenty-three ...
Borer J S - - 1978
In patients with aortic regurgitation,, left ventricular dysfunction at rest, which is associated with a poor long-term prognosis, often develops before severe symptoms. To determine whether evidence of left ventricular dysfunction could be detected before it appeared at rest, 43 patients with severe aortic regurgitation were studied using radionuclide cineangiography ...
Khalsa A - - 1978
Adequate control of ventricular rate in patients with chronic atrial fibrillation (AF) may not be achieved with digitalis alone. In the present study the additional effect of two different doses (50 mg and 50 +/- 50 mg) of oral metoprolol, a new selective beta-blocking agent, on ventricular rate in patients ...
Koch G - - 1978
The anti-arrhythmic effect of oral mexiletine on exercise-induced ventricular arrhythmia was studied in a double blind trial of 10 patients suffering from ventricular ectopic beats of different origins. There was a good reproducibility of the amount of ectopic ventricular activity between consecutive exercise tests when no active drug was given. ...
Stanley T H - - 1978
Cardiovascular dynamics and left ventricular work were evaluated in 15 resting, standing, and treadmill-exercised calves before and at periodic intervals after their natural hearts (NH) were replaced with an artificial heart (AH). Standing produced increases in heart rate, cardiac output, oxygen uptake, and left ventricular work and decreases in mean ...
Horwitz L D - - 1978
The effect of brief periods of regional ischemia upon left ventricular pump performance was studied in nine dogs standing quietly at rest and during running exercise on a treadmill. Transient occlusions of the left circumflex coronary artery resulted in increase in heart rate at rest (+30 beats/min) but not during ...
Markiewicz K - - 1978
The left ventricular systolic function was studied in 123 healthy men aged 23-24 years under the influence of exercise and during a two-hour restitution period. Left ventricular systolic time intervals (LVSTI) were evaluated by means of the Blumberger method with Holldack's modification before the exercise, immediately after its termination and ...
James F W - - 1978
This chapter has demonstrated the diagnostic capability and feasibility of documenting functional abnormalities during dynamic stress in a pediatric population. The overview confirms that a controlled exercise procedure can be performed routinely in ambulatory children with or without cardiovascular disease and should be included in the clinical evaluation of specific ...
Nixon J V - - 1978
The effect of propranolol on exercise-induced or augmented ventricular ectopy was studied in sixteen male patients, six of whom had documented coronary artery disease. Fifteen patients were exercised after two weeks of oral therapy, fourteen after single oral therapy and eight patients after intravenous therapy. Propranolol dosage was titrated to ...
Hirschhaut E - - 1978
The EKG response to exercise and the working capacity in a group of 70 patients with positive serology for Chagas' disease has been determined by stress testing on a bicycle-ergometer, in order to establish the usefulness of such a test in the early diagnosis of Chagas' cardiomyopathy. The exercise EKG ...
Fletcher G F - - 1977
Five patients with ischemic heart disease were resuscitated after experiencing ventricular fibrillation in a medically supervised exercise program. Four subsequently had successful myocardial revascularization (three prior to hospital discharge), and three have returned to an exercise prescription of reduced intensity. Multivessel operative coronary disease is common in patients experiencing ventricular ...
Horwitz L D - - 1977
The effect of ouabain on left ventricular function in nonfailing hearts was assessed in 14 chronically instrumented dogs during graded treadmill exercise. At rest, ouabain increased the maximum first derivative of the left ventricular pressure (dp/dtmax) and stroke volume by 38% and 16%, respectively. No change occurred in end-diastolic left ...
Kennedy H L - - 1977
To determine if maximal exercise treadmill testing influences the occurence of ventricular arrhythmia in the hours after exercise, 45 myocardial infarction and 22 angina pectoris patients (New York Heart Association Class I-II), and 23 normal subjects were examined with 24-hour ambulatory electrocardiographic Holter recordings before and after exercise testing. Comparison ...
Gilbert C A - - 1977
Adaptive cardiac responses to isotonic training were studied with echocardiographic measurement of cardiac dimensions and function in 20 endurance runners whose maximal aerobic capacity on the treadmill was 4.88 +/- 0.13 (mean standard error of mean) liters of oxygen/min. They were compared with 26 young sedentary control subjects whose capacity ...
Yasui H - - 1977
The effects of complete right bundle branch block (CRBBB) on the early postoperative course and long-term follow-up results of closure of ventricle septal defect (VSD) were investigated. (1) Postoperative change in cardiothoracic ratio (CTR); In patients whose ratio of total pulmonary resistance to total systemic resistance (Rp/Rs) was larger than ...
Sheps D S - - 1977
Two exercise tests were performed with an intervening rest period of 45 minutes in a group of 13 subjects with previously identified exercise-induced ventricular arrhythmias and no resting arrhythmias. Both normal subjects and patients with heart disease were included in the group. The level of stresss was equal in both ...
Stone H L - - 1977
Exercise training (T) was accomplished in 21 mongrel dogs. The animals were instrumented to measure ascending aortic flow, left ventricular pressure, and left atrial pressure. They were allowed to recover for 4 wk following surgery before accomplishing a standardized submaximal test (SMT). The exercise program alternated daily between sprint and ...
McHenry P L - - 1977
Maximal treadmill exercise tests were performed by 586 male members of the Indiana State Polic Force who were free of clinical evidence of cardiovascular disease. The study population was categorized into groups according to cigarette smoking experience and subgroups according to age and number of pack-years of exposure. There were ...
Pickering T G - - 1977
Two people with frequent premature ventricular contractions and bigeminal rhythm not associated with other signs of heart disease, learned to suppress the arrhythmia using a biofeedback technique. In both cases, physical exercise and atropine suppressed the arrhythmia, and in both the learned control was related to the development of tachycardia. ...
Karlsson E - - 1977
Ten patients with a persistent ventricular arrhythmia, but no other sign of heart disease, were studied by means of an exercise test performed 4 times with a fixed work load, over 30--40 min. No drug was given in the first exercise test and in the others phenytoin, procainamide or practolol ...
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