Search PubMed⌕ Search

Biomedical subjects

D E Manyari

Publications and source records attributed to D E Manyari.

At least 55 records · Page 3Linked to original sources
PubMed1984

The clinical and hemodynamic effects of propranolol, pindolol and verapamil in the treatment of exertional angina pectoris.

The efficacy of two beta-receptor antagonists, propranolol and pindolol, was compared with that of a calcium antagonist, verapamil, in the treatment of exertional angina pectoris in 22 men (mean age 51 years). The clinical response and left ventricular function were evaluated with treadmill exercise and with radionuclide ventriculography performed while the patient was at rest or exercising supine with a bicycle ergometer. All the treatments significantly prolonged exercise duration (p less than 0.001) and reduced the number of patients terminating treadmill exercise because of angina (p less than 0.05). The resting heart rate was decreased markedly (p less than 0.001) by propranolol but only slightly (p less than 0.05) by pindolol and verapamil. The left ventricular ejection fraction during rest was unchanged by any treatment, but that during exercise was improved (p less than 0.05) by all the treatments. Patients who failed to gain relief from angina with one of the drugs often responded to another, and adverse reactions occurring with one drug did not necessarily occur with another. In summary, pindolol and verapamil were safe and effective alternatives to propranolol in the treatment of the exertional angina pectoris of these patients.

Adrenergic beta-Antagonists↗
PubMed1983

Left and right ventricular function at rest and during bicycle exercise in the supine and sitting positions in normal subjects and patients with coronary artery disease. Assessment by radionuclide ventriculography.

To assess the hemodynamic influence of posture during radionuclide cardiac studies, rest and exercise electrocardiographically gated blood pool cardiac scintigraphy was performed in the supine and sitting positions in 22 normal subjects and in 20 patients with coronary artery disease (CAD). In normal subjects, left ventricular ejection fraction was higher in the sitting position both at rest (67 +/- 6% versus 64 +/- 5%, p less than 0.01) and during exercise (79 +/- 9% versus 76 +/- 6%, p less than 0.05). Left ventricular end-diastolic volume in the sitting position was smaller at rest (by 19 +/- 26%, p less than 0.001), but this variable was similar in both positions during exercise (p greater than 0.05). Left ventricular end-systolic volume was smaller in the sitting position both at rest, by 26 +/- 31 percent, and during exercise, by 14 +/- 20% (p less than 0.001). Left ventricular end-diastolic volume increased from rest to exercise, in the sitting position by 31 +/- 23% (p less than 0.001) and in the supine position by 6 +/- 22% (p greater than 0.05). In patients with CAD, similar left ventricular ejection fractions in both postures were found at rest and during exercise. Left ventricular end-diastolic volume in the sitting posture was smaller at rest by 16 +/- 22% (p less than 0.01) and during exercise by 8 +/- 18% (p less than 0.05). Sitting left ventricular end-systolic volume was smaller by 18 +/- 20% (p less than 0.001) at rest and by 14 +/- 21% (p less than 0.01) during exercise. Left ventricular end-diastolic volume increased from rest to exercise, in the sitting position by 45 +/- 36% (p less than 0.001) and in the supine position by 32 +/- 51% (p less than 0.01). Despite significant hemodynamic differences, the value of rest-exercise radionuclide cardiac studies to detect CAD was similar in the 2 positions.

Adult↗
PubMed1983

Resting and exercise left ventricular function in patients with hypertrophic cardiomyopathy.

Left ventricular ejection fraction (EF) at rest and during exercise was measured in 19 patients with hypertrophic cardiomyopathy (HCM) by means of radionuclide angiography. The results were compared to those in 20 normal subjects. Based on hemodynamic data, patients with HCM were divided into three groups. In group I, no demonstrable left ventricular outflow obstruction, there were five patients; their mean EF increased from 68% +/- 8.9 (+/- SD) at rest to 74% +/- 9.2 during exercise (p less than 0.05). In group II, latent obstruction, there were six patients; their mean EF at rest (75.2% +/- 8.2) and at peak exercise (78.7% +/- 6.7) was not statistically different (p greater than 0.05). Group III, obstruction present at rest, consisted of eight patients; EF at rest (82.6% +/- 8.5) decreased significantly during exercise (75.6% +/- 7.7, p less than 0.01). In normal subjects resting EF was 66.3% +/- 7.6; it increased to 76.4% +/- 7 (p less than 0.001). Exercise duration and heart rate-blood pressure product were lower in groups II and III. Thus there are significant differences in left ventricular systolic function both at rest and during exercise between these three major hemodynamic subgroups. These findings emphasize the importance of such a hemodynamic classification of HCM.

Adult↗
PubMed1983

Effect of pericardiocentesis on right and left ventricular function and volumes in pericardial effusion.

To assess the effects of pericardial effusion on ventricular performance and volumes, electrocardiographically gated blood pool cardiac scintigraphy was performed immediately before and after 14 pericardiocenteses in 10 patients, 7 men and 3 women, aged 28 to 73 years (mean 50). Cardiac tamponade was present in 5 patients. After removal of 140 to 1,100 ml of pericardial fluid (527 +/- 305 ml [mean +/- standard deviation]), left ventricular (LV) ejection fraction increased from 63 +/- 5 to 64 +/- 4% (p greater than 0.05) and right ventricular (RV) ejection fraction decreased from 47 +/- 4 to 46 +/- 2% (p greater than 0.05). LV end-diastolic and end-systolic volumes increased (p less than 0.01) by 28 and 33%, and RV volumes by 40 and 43%, respectively. There were 8 patients with normal LV function (ejection fraction greater than 60%) and 6 patients with subnormal LV function. Changes in ejection fraction were nonsignificant in the 4 subgroups. LV end-diastolic volume changes were more marked (p less than 0.01) in patients with cardiac tamponade (+ 56%) than in those without tamponade (+ 17%), and in those with normal LV function (+ 36%) than in those with subnormal LV function (+ 21%). RV end-diastolic volume increased more markedly (p less than 0.05) in patients with tamponade (+ 72%) than in those without tamponade (+ 23%), but were similar in patients with normal (+ 38%) and abnormal (+ 43%) LV function. After pericardiocentesis, RV volume increased more markedly than did LV volume. Thus, hemodynamic and clinical improvement after pericardiocentesis may be related only to an increase in stroke volume. RV and LV ejection fraction, a measure of myocardial contractility, was not affected significantly by the presence of pericardial effusion, even in those patients who had cardiac tamponade.

Adult↗
PubMed1983

Pindolol and propranolol in patients with angina pectoris and normal or near-normal ventricular function. Lack of influence of intrinsic sympathomimetic activity on global and segmental left ventricular function assessed by radionuclide ventriculography.

To investigate the role of intrinsic sympathomimetic activity on left ventricular (LV) function during antianginal therapy with beta-adrenoreceptor antagonists, 23 patients with chronic, exercise-induced angina pectoris and normal or near normal LV function underwent radionuclide ventriculography at rest and during exercise, during 3 randomly allocated periods: (a) treatment with oral propranolol, a drug without intrinsic sympathomimetic activity, 40 to 80 mg 4 times a day; (2) treatment with pindolol, a drug with marked intrinsic sympathomimetic activity, 5 to 10 mg 2 times a day; and (3) a control period. During the control period, the LV ejection fraction decreased from rest (58.9 +/- 8.2%) to exercise (54.3 +/- 10.7%), and the wall motion score decreased from 0.57 +/- 1.08 at rest to 2.39 +/- 2.10 during exercise, p less than 0.001. After propranolol, the ejection fraction did not change significantly at rest (57.2 +/- 8.1%) but improved during exercise (56.8 +/- 11.8%), compared with control values. After pindolol, the ejection fraction did not change at rest (57.9 +/- 8.6%) but improved during exercise (56.9 +/- 8.1%), compared with control values. Similarly, the wall motion score after administration of both agents did not change significantly at rest, but improved during exercise (p less than 0.001). The number of anginal episodes, nitroglycerin tablets consumed, and magnitude of S-T segment depression decreased significantly with both pindolol and propranolol. With both drugs, a similar improvement in exercise tolerance and a similar decrease in exercise heart rate and blood pressure were obtained. It is concluded that pindolol and propranolol, beta-adrenoreceptor antagonists with and without intrinsic sympathomimetic activity, respectively, have similar effects on global and regional LV function in patients with angina pectoris, at doses producing equal suppression of exercise heart rate and similar antianginal effect.

Adult↗
PubMed1983

Electrocardiographic recognition of variant angina during permanent pacing.

We present a patient with a permanent ventricular pacemaker who was investigated for episodes of chest pain associated with syncope. Ambulatory electrocardiographic monitoring showed essentially paced rhythm. ST segment elevation of the paced beats was observed during spontaneous chest pain, but the significance of this finding was initially unclear in the context of the abnormal repolarization associated intrinsically with paced rhythm. At angiography, coronary spasm was demonstrated after ergonovine, and this was associated with ST segment elevation during paced rhythm and with chest pain. We conclude that ST segment elevation may indicate myocardial ischemia even when observed in the face of abnormal repolarization associated with paced rhythm.

Angina Pectoris, Variant↗
PubMed1982

A simple echocardiographic method to detect atrioventricular dissociation. A useful aid in the differential diagnosis of regular tachycardia with wide QRS complexes.

Regular tachycardia with wide QRS complexes may be difficult to classify as supraventricular (SVT) or ventricular (VT) without electrophysiologic studies. We felt that hemodynamic differences between VT and SVT should allow their distinction by echocardiography. In this study, we utilized high speed M-mode echocardiography in the usual projections in eight patients during tachycardia. Two patients had spontaneous VT and three had spontaneous SVT with aberrant conduction. The remaining three were patients in sinus rhythm undergoing electrophysiologic studies in whom right ventricular (RV) pacing (induced VT), right atrial (RA) pacing (induced SVT) and sequential RV-RA pacing (induced VT with 1:1 retrograde conduction) were carried out. The echocardiographic parameters studied included: left ventricular internal dimensions, time during which the mitral valve remained open (MVOT), left ventricular ejection time (LVET) and pre-ejection period. We measured 20 consecutive beats and for each parameter defined its variability. During A-V dissociation (VT, RV pacing) there was always a striking beat-to-beat variability in the values of MVOT (68 percent to 129 percent) and in LVET (41 percent to 175 percent). In contrast, during A-V association (SVT, sequential RV-RA pacing, sinus rhythm) the maximal variability of MVOT and LVET was 22 percent and 12 percent, respectively. Variability during A-V dissociation could be explained by asynchronous timing of atrial systole. We conclude that echocardiography can readily identify atrioventricular dissociation, a feature heavily in favor of a diagnosis of VT.

Adult↗
PubMed1982

Quantitative assessment of aortic valvular insufficiency by radionuclide angiography.

Gated blood pool cardiac scintigraphy was used to assess quantitatively the degree of aortic insufficiency in 25 patients. The difference between the number of counts, corrected by time and background, at end-diastole and end-systole (stroke counts) in the left ventricle and right ventricle were used as indices of total (forward plus regurgitant) stroke volume and forward stroke volume respectively. From these, two radionuclide parameters were measured: 1) regurgitant fraction = 100 x (left ventricular stroke counts--right ventricular stroke counts)/left ventricular stroke counts; and 2) left ventricular/right ventricular stroke volume ratio = left ventricular stroke counts/right ventricular stroke counts. A good correlation was found between the regurgitant fraction calculated by contrast and Doppler studies and the two radionuclide parameters: regurgitant fraction (r = 0.81) and stroke volume ratio (r = 0.80). In 20 patients without valvular heart disease studied by the radionuclide method, the results of regurgitant fraction (11 +/- 10 percent, mean +/- SD) and stroke volume ratio (1.13 +/- 0.12) closely approached the theoretical normal values of 0 and 1.00, respectively. These results validate previous observations and demonstrate the value of blood pool cardiac scintigraphy in the noninvasive quantitation of aortic insufficiency in the clinical setting.

Adult↗
PubMed1981

Left ventricular function during graded exercise in patients with coronary artery disease and in control subjects.

The left ventricular function of 30 patients with coronary artery disease and 11 control subjects was studied by electrocardiography gated cardiac blood pool scintigraphy as the participants lay on their backs and either rested or exercised on a cycle ergometer at graded levels on intensity. The control subject showed a progressive increase in ejection fraction from rest (51% +/- 7%) to intermediate (56% +/- 10%, P less than 0.05) and maximum levels of exercise (64% +/- 10%, P less than 0.001). All the patients showed a decrease in ejection fraction from rest (42% +/- 16%) to their maximal level of exercise (36% +/- 11%, P less than 0.001). However, the response of some of the patients to intermediate exercise ranged from a decrease or no change to an increase in ejection fraction. Thus, exercise at maximal intensity is necessary to induce the left ventricular dysfunction that is diagnostic of coronary artery disease.

Coronary Disease↗
PubMed1981

Quinidine therapy and digitalis toxicity.

In a 90-year-old man undergoing prolonged digitalis therapy, digitalis toxicity was precipitated by the administration of quinidine. The electrocardiogram revealed supraventricular bidirectional tachycardia, a rare but characteristic arrhythmia associated with digitalis toxicity. Upon withdrawal of digoxin, the clinical and ECG signs disappeared. A diagnosis of digitalis toxicity rather than quinidine intolerance led to appropriate treatment.

Aged↗
PubMed1981

Left ventricular function and volume during supine exercise in subjects with coronary artery disease.

Left ventricular function and volume changes during supine isotonic exercise were assessed in 32 patients with coronary artery disease (CAD) and 12 normal subjects by electrocardiographically gated blood pool cardiac scintigraphy. Ejection fraction (EF) in normal subjects was 49 +/- 10% at rest, 54 +/- 10% during intermediate exercise (P less than 0.05 vs. rest), and 62 +/- 14% during maximal exercise (P less than 0.01 vs. rest). In patients with CAD the resting EF was 42 +/- 14%, 43 +/- 23% at intermediate exercise (P = nonsignificant vs. rest) and 36 +/- 11% at maximal exercise (P less than 0.01 vs. rest). Changes of average and maximal ejection rates from rest to exercise were similar to those of EF but had a lesser degree of statistical significance. End-diastolic volume index (EDVI) in patients with CAD, at intermediate exercise was equal to that at rest, but it increased during maximal exercise (P less than 0.01). In normal subjects EDVI did not change with exercise. Thus, during supine exercise the Frank-Starling mechanism is apparent in patients with CAD but not in normal subjects. Analysis of EF response to exercise is a highly sensitive technique to detect CAD provided that adequate exercise is achieved.

Adult↗
PubMed1980

Radionuclide left ventricular angiography during exercise in ischemic heart disease.

Radionuclide angiocardiography during exercise is one of the latest advances in nuclear cardiology and is being introduced into clinical practice. In this article the pathophysiological principles of this technique and the method with which it is used to evaluate patients with ischemic heart diseases are outlined, the various patterns of response in these patients are illustrated, and factors that limit the interpretation of the results, including the level of exercise achieved, are discussed.

Cardiac Volume↗
PubMed1978

Detection of pericardial effusion by chest roentgenography and electrocardiography versus echocardiography.

To determine the sensitivity and specificity of chest roentgenography and electrocardiography in the detection of pericardial effusion, echocardiography was used as the diagnostic standard. Chest roentgenograms and electrocardiograms of 124 patients, 57 of whom had pericardial effusion, were read without knowledge of the echocardiographic interpretation. The sensitivity of roentgenographic diagnosis was low (20%), as was that of diagnosis from decreased voltage on the electrocardiogram (26%). The specificity of the chest roentgenogram was 89% and that of the low-voltage electrocardiogram 97%. The high specificity of the low-voltage electrocardiogram may have been due in part to the exclusion of obese and emphysematous subjects from the study. When cardiomegaly detected roentgenographically or a low-voltage electrocardiogram or both were considered as evidence of pericardial effusion, sensitivity improved to 82% but specificity declined to 29%. It is concluded the chest roentgenography and electrocardiography are unsatisfactory as screening investigations for the detection of pericardial effusion.

Echocardiography↗
PubMedDate not supplied

Virtual congresses.

A new form of scientific medical meeting has emerged in the last few years--the virtual congress. This article describes the general role of computer technologies and the Internet in the development of this new means of scientific communication, by reviewing the history of "cyber sessions" in medical education and the rationale, methods, and initial results of the First Virtual Congress of Cardiology. Instructions on how to participate in this virtual congress, either actively or as an observer, are included. Current advantages and disadvantages of virtual congresses, their impact on the scientific community at large, and future developments and possibilities in this area are discussed.

Cardiology↗