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Query: UMLS:C0011570 (depression)
 172,036 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Atrial pacemaking under conditions of relative constancy (40 or 50% of the preceding cycle) enables us to calculate the immediate sino-atrial conduction time (retrograde and antegrade) (SACT). 17 patients were chosen for their normal sino-atrial function under spontaneous changes of the sinus cycle (SC). In each case, a significant inverse linear relationship was found between SACT and the corresponding SC. The mean correlation slope was -0.36 in 10 patients with no post-pacing depression (PPD). The slope was greater in 7 patients with a PPD (-0.89); if this depression is taken into account when the SACT is calculated, the slope decreases. In 5 patients, atropine (1 mg I.V. reduced the mean value of SC, and shortened (constant relative value) the SACT. The mechanisms for the spontaneous and induced variations in the sinus output are discussed; it may be that there are substitute pacemakers within the cells of the sino-artrial node, which are affected by variations in sympathetic or parasympathetic activity or by pacing. In clinical practice, automatism and conduction with the sinus node should be interpreted as inter-related functions, both under normal conditions and after vagal block.
Arch Mal Coeur Vaiss 1978 Oct
PMID:[Evaluation of sino-atrial function using the method of extrasystole induced by constant-relative premature impulses. 1. Method and normal results]. 8 56

The total immediate sino-atrial conduction time (SACT) as calculated by constant relative pacing, 40 or 50% of the immediate sinus cycle (SC), normally varies inversely with the SC. 50 patients were investigated by this method. In 38 patients without sino-atrial block (SAB) on the surface ECG, it was found that the mean slope of correlation between SACT and SC varied with the shape of the curve of Strauss and with the presence or absence of a post-pacing depression. The smallest slope was found in the group in which the curve of Strauss was horizontal in zone II, and in which there was no depression. In the groups with a rising zone II, comparative use of pacing with a fixed relationship in milliseconds suggested a phenomenon of decreasing retrograde conduction. In cases with sinus arrhythmia and a Strauss curve with scattered coordinates, the relationship between SACT and SC was maintained. 1st degree right-sided SAB should therefore be defined as a function of the immediate SC. In 12 other patients with SAB on the surface ECG, the immediate SACT was greatly lengthened so as to be immeasurable, and bore no relationship to the SC.
Arch Mal Coeur Vaiss 1978 Oct
PMID:[Evaluation of sino-atrial function using the method of extrasystole induced by constant-relative premature impulses. 2. Application in 50 normal and abnormal studies]. 8 57

The various factors influencing the result of treatment have been studied in a series of 100 consecutive patients undergoing aorto-coronary bypass graft surgery. There were three operative deaths and twelve cases of post-operative infarction. Longterm, 85% of them were three year survivors, clinical improvement being maintained in 84% of them. Post-operative tests showed that 70% of patients have no pain on the maximal exercise test, but 48% had ischaemic depression of the ST segment. From among the 47 patients who had follow-up arteriography, 78% of the grafts were patent, but no improvement of the contractility of the left ventricle could be demonstrated (pre-operative ejection fraction 47 +/- 3%, post-operative 49+/- 3%). The pre-operative clinical features rarely give any indication of the prognosis. The same is true in the present series of the condition of the left ventricle, bearing in mind the fact that patients with grossly impaired ventricular contractility (ejection fraction below 30%) were routinely excluded from surgery. It is essentially the state of the coronary arterial network, as assessed by a score made up from the degree and number of stenoses, the quality of the distal bed, and the anatomical distribution, which will pick out those patients more at risk both from the surgery and from post-operative death and in whom the longterm result is likely to be disappointing with no improvement in function, with obstruction of the grafts, or with secondary death.
Arch Mal Coeur Vaiss 1978 Jul
PMID:[Analysis of factors which can influence results of aortocoronary bypass surgery]. 10 77

A hundred cases have been studied and divided into three categories:--60 normal subjects;--30 coronary subjects with a positive exercise test;--10 subjects with defective nervous control of the circulation; using the exercise test, we studied the effects of hyperventilation on repolarisation of the ventricle. In the normal subjects there was no ischaemic depression of the ST segment, but there were minor changes in repolarisation which affected the T wave in 73% of subjects and were essentially posterior in distribution. In the coronary subjects, we found three with ischaemic depression of the ST segment and one with ST elevation of 2.5 mm (6.7% of the coronary subjects). This last finding is evidence against the commonly held hypothesis that reproduction of ST depression by hyperventilation during the exercise test indicates a false positive test. In the patients with defective nervous control of the circulation, 9 had an ischaemic type of ST depression, either as a new feature or as a more severe one compared with that found at rest. The mechanism by which these depressions are produced has not been totally explained:--in the cases with defective nervous control of the circulation, it appears that latent increased sympathetic activity is increased by the hyperventilation;--in the coronary subjects, it may be caused by true ischaemia or by an associated defect in nervous control of the circulation.
Arch Mal Coeur Vaiss 1978 Jul
PMID:[Hyperventilation test in coronary disease: a comparison with a bicycle ergometer exercise test. Report of 100 cases]. 10 78

We have seen a case with spasm of the right coronary artery coming on during exercise ergometry in the course of a coronary arteriogram. The patient had angina pectoris spontaneously and on exercise. Bicycle ergometry was repeated four times by the same method, and was positive in three; in two of these there was angina and ST elevation in II, III, aVF, and ST depression in I, aVL and V2 to V5. On one occasion the test was negative, the patient having taken a trinitrin tablet one hour before the test. Repeating the exercise test during coronary arteriography showed spasm of the right coronary artery and elevation of the segment ST in II, III and aVF; this disappeared after trinitrin treatment.
Arch Mal Coeur Vaiss 1978 Jul
PMID:[Coronary spasm on exercise. Demonstration of a case by coronary angiography]. 10 83

Sixty-five patients, convalescent from a first myocardial infarction (anterior in 24 cases; inferior in 41 cases), underwent an effort electrocardiogram on a treadmill and coronary arteriography. In the anterior infarcts, coronary arteriography showed single vessel disease (anterior descending artery) in 54% of cases and double or triple vessel disease in the others. The effort test was positive in only 25% of patients with an anterior infarct. The presence of stenotic lesions of the circumflex artery and/or right coronary artery was unsuspected in 63% of patients. In the inferior infarcts, there was a significant stenosis of the anterior descending artery in 51% of the cases. The effort test was positive in 54% of patients and in 77% of those the anterior descending artery showed a significant stenosis. The appearance (or increase) of ST elevation greater than or equal to 1 mm in the leads facing the infarcted zone was an indication of more severe deterioration in left ventricular function as shown by a more marked reduction in ejection fraction and a more extensive akinetic region. The co-existence of ST elevation in the leads facing the infarcted zone and of ST depression greater than or equal to 1 mm in the reciprocal leads always indicated that another major vessel was involved, but this was only found in 25% of cases in this series.
Arch Mal Coeur Vaiss 1978 Sep
PMID:[Effort electrocardiography and coronary arteriography following a 1st myocardial infarction. Critical study of the effort test]. 10 91

We have studied the fate of 49 patients with stenosis of the trunk of the left coronary artery of more than 50%. The follow-up period extends from 1,5 years to 5 years (with a mean of 33.83 +/- 13.55 months). The clinical picture was not characteristic. Unstable angina was found in 59% of cases. The exercice test (29 patients) was positive in 100%, with a mean depression of 3.3 mm. Stenosis of the trunk, which is rarely an isolated condition (8% of cases), is usually associated with disorders of the other main coronary vessels. Twenty six patients underwent surgery. Thirteen patients who were operable were treated medically. The performance of the left ventricle and the degree of involvement of the coronary arteries were comparable in these two groups. Seven inoperable patients were treated medically. Actuarial survival curves show a significant difference (p less than 0.01) in survival after two years between the operated cases (88%), the operable cases treated medically (60%), and the inoperable cases (57%). The decreased mortality of the operated cases corresponds also with a greater functional capacity in the survivors compared with that of the cases treated medically.
Arch Mal Coeur Vaiss 1978 Oct
PMID:[The fate of patients with stenosis of the trunk of the left coronary artery]. 10 83

31 patients presenting with Prinzmetal variant angina were divided into three groups according to their angiographic appearances. Group I comprised 9 patients with normal or coronary arteries with lesions less than 50% narrowing. Group II comprised 12 patients with single vessel disease. Group III comprised the other 10 patients with significant lesions on two or all three principal arteries. No clinical or electrocardiographical differences were found between the groups as to age, sex or the clinicapresentation of the chest pain. Most patients with normal or nearly normal coronary arteries had normal electrol cardiogrammes between attacjs (8 out of 9) and electrical changes mainly over the inferior wall (8 out of 9). Exercise electrocardiography reproduced ST elevation in 4 of the 9 patients but, in contrast to the patients in the other two groups, never ST depression. However, these features are not specific for patients in Group I as they were observed in 4 patients in the other two groups. Spontaneous or induced coronary spasm were observed in 27 patients, confirming its role as the mechanism of Prinzmetal angina, whatever the anatomical appearance of the coronary tree.
Arch Mal Coeur Vaiss 1979 Jan
PMID:[Clinical and angiographic study and pathogenic mechanism of Prinzmetal's angina. Apropos of 31 cases]. 10 80

The electrophysiological effects of anti-arrhythmic drugs in man may be classified in three groups: -- Group I: comprising drugs whose characteristic action is on the AV node (beta blockers, verapamil, digitalis) The nodal conduction time (A-H interval) and refractory periods are increased. -- Group II: comprising drugs acting on the His-Purkinje system, the AV nodal conduction staying unchanged. This group has two sub-groups. Sub-group A: these drugs delay the His-Prukinje conduction (increased H-V interval). Examples are quinidine, procainamide, disopyramide, ajmaline, chloro-acetyl-ajmaline. In addition these drugs usually increase the atrial refractory periods and those of accessory pathways. Sub-group B: the His-Purkinje conduction is unchanged but the refractory periods are modified: lengthened (bretylium tosylate) or shortened (diphenylhydantoin, lignocaine, mexiletine). -- Group III: which includes amiodarone and aprindine whose effects are mixed: on the one hand AV nodal depression, and on the other, alteration of the His-Purkinje conduction manifested by an increased H-V internal (aprindine) or refractory periods (amiodarone). These preparations also increase the refractory periods of accessory AV pathways and amiodarone increase the refractory periods of the atria. This type of classification could help towards a more rational clinical approach to the use of anti-arrhythmic drugs.
Arch Mal Coeur Vaiss 1979 Jan
PMID:[Electrophysiological effects of anti-arrhythmia agents in man. Attempt at classification]. 10 85

The direct action of nitrate derivatives on myocardial contractility is not fully understood. The effects of Glyceryl Trinitrate (1 mM/L.) and Sodium Nitro prussiate (3 X 10(-5) M/L.) on papillary muscle were studied during 30 minutes hypoxia followed by 60 minutes reoxygenation: Both conditions were analysed every 5 minutes: 1. Contractility was assessed by maximal shortening velocity with no load (Vmax), maximal isometric force (PF), number of active cross-bridges and peak time (TPF), a characteristic of the period of activity. 2. Relaxation was assessed by the relaxation velocity (V relax) and the 1/2 relaxation time (THR). The two nitrate derivatives had the same effects: during anoxia, a notable reduction of the maximal force was observed; myocardial depression continued during the first 15 minutes of reoxygenation. After the 30th minute of investigation all parameters increased significantly (107-110 p. 100, p less than 0,01); TPF and THR returned to normal. A positive inotropic effect and improvement of the relaxation phase were observed at the end of reoxygenation. This effect is not attributed to improved segmental performance especially as it occurred at dosages close to those used in therapeutics.
Arch Mal Coeur Vaiss 1979 Apr
PMID:[Effect of nitrate derivatives on the contractility and relaxation of papillary muscle in hypoxia and reoxygenation]. 11 41


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