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R Adamec

Publications and source records attributed to R Adamec.

At least 55 records · Page 3Linked to original sources
PubMed1985

[Triggering of paroxysmal auricular fibrillation. Study using continuous electrocardiographic recording (Holter system)].

Recent studies of the mode of initiation of atrial fibrillation (AF) have emphasises the role of the autonomic nervous system, vagal and sympathetic, in the development of this arrhythmia. Continuous 24 hour electrocardiographic recording (Holter monitoring) is a good method of studying arrhythmias. The role of vagal or sympathetic stimulation was evaluated by retrospective analysis of 3 000 Holter recordings performed in our department. Three groups of patients were identified: Group I, patients with bradycardia at the time of onset of AF (sinus rhythm less than 60/min); Group II, patients with sinus rhythms greater than or equal to 60/min at the time of onset of AF. Some of the rapid atrial arrhythmias encountered in the sick sinus syndrome may be confused with AF on Holter monitorings; patients with signs of sinus node dysfunction were therefore set apart (Group III). The following features were studied in all patients: the morphology of the sinus P wane, the duration of the PR interval, the permeability of the atrioventricular node at the start of AF, the presence of arrhythmias before AF and the time of day of the episodes of AF. The highest incidence of prolongation and abnormalities of the P wave and increased AV conduction at the beginning of AF was observed in Group I. There was also a marked prevalence of supraventricular beginning before AF and most episodes of AF were observed during the night. In groups II and III no attacks of AF were observed at sinus rhythm greater than 94/min. The extrasystole initiating AF had the same average coupling interval in all three groups.(ABSTRACT TRUNCATED AT 250 WORDS)

Aged↗
PubMed1985

[Late potentials: non-invasive detection in coronary disease and relation to severe ventricular arrhythmia].

Using high-gain amplification and signal averaging techniques, we tried to determine the clinical significance of ventricular late potentials (LP). 85 subjects were included in this study. No LP were detected in normal subjects (n = 25), nor in patients with various non-coronary cardiopathies who had presented ventricular tachycardia and/or fibrillation (VT/VF) (n = 10). LP were recorded only in patients with coronary heart disease (CHD) (n = 50). The prevalence of LP was 50% (9/18) in patients with a history of VT/VF (vs 12.5% = 4/32 in patients without such a history, p less than 0.02). We also found a prevalence of 50% (11/22) in patients with a ventricular aneurysm (vs 7.1% = 2/28 in patients without an aneurysm, p less than 0.01). The prevalence reached 80% (8/10) in patients with VT/VF and a ventricular aneurysm and it was only in this latter group of patients that the interval between the peak of the R wave and the end of ventricular electrical activity exceeded 100 ms (mean 111.2 +/- 12 ms, vs 50 +/- 8 ms in normal subjects, p less than 0.001). In all the cases submitted to surgery, the LP disappeared after resection of the aneurysm. In conclusion, LP, when of long duration, should be considered as a hallmark of malignant ventricular arrhythmias in patients with CHD.

Adolescent↗
PubMed1984

[Prognostic value of the late potentials of ventricular activation in coronary disease].

Identification of subsets of patients with coronary artery disease (CAD) who are prone to ventricular tachycardia or fibrillation (VT/VF) and to sudden arrhythmic death still represents one of the major problems in clinical cardiology today. Ninety-two patients with CAD were included in this prospective study, which was designed to assess the prognostic significance of ventricular late potentials (VLP) detected non-invasively using high-gain electrocardiography and signal averaging. The results clearly demonstrate that the presence of VLP increases the risk of VT/VF and the risk of sudden arrhythmic death in CAD patients. Because of its high sensitivity and non-invasiveness, high-gain electrocardiography should be included among the various electrophysiological investigations used to assess prognosis in CAD patients.

Adult↗
PubMed1984

[Evaluation of a delayed-action beta blocker by 24-hour ambulatory recording of the arterial pressure].

Twelve students aged 21 to 39 years (mean age 26) with borderline hypertension underwent three 24 hours ambulatory recordings of blood pressure using an Avionics Pressurometer II device: the first recording under basic conditions, the second after taking placebo and the third after being treated for 3 days with a betablocker of long acting effect (oxprenolol R 160 mg) in a randomized study. The blood pressure mean profile showed a double peak during daily activity with a progressive lowering of the blood pressure during sleep. The effect on the blood pressure of long acting oxprenolol begins four hours later, remains for about ten hours and may be still present next day. The shape of the circadian blood pressure profile is not modified. No significant difference between the pressure profiles on the basic conditions and placebo is noticed.

Adult↗
PubMed1984

[1:1 atrial flutter in an elderly patient: one of the methods of discovering Wolff-Parkinson-White syndrome. Apropos of a case in an adult].

Atrial flutter with 1:1 atrioventricular conduction giving rise to a ventricular rhythm of 240/min in an 80 year old man was the first sign of the Wolff-Parkinson-White syndrome; all previous electrocardiogrammes had shown no evidence of pre-excitation. It was only on the fifth day of hospitalisation that the ECG showed a short PR interval with a delta wave. This case illustrates that: --all supraventricular arrhythmias with abnormally high ventricular rates (over 220/min in adults) should alert to the possibility of an accessory atrioventricular pathway; --rapid atrioventricular conduction may be the first sign of an accessory pathway; --the differential diagnosis lies between an accessory atrioventricular pathway and an atriohisian tract; --digitalis, which may shorten the refractory period of the accessory pathway, is contraindicated in patients with a Kent bundle.

Aged↗
PubMed1983

[Non-invasive detection of late potentials of ventricular activation: identification and significance in coronary disease].

Using a high-amplification electrocardiograph with signal averaging, an attempt has been made to determine the prevalence of delayed potentials of ventricular activation (DPVA) in coronary heart disease (CHD) and their relation to ventricular tachycardia and/or fibrillation (VT/VF). No DPVA could be recorded in normal subjects (n = 25) or in patients with various cardiopathies with VT/VF but without CHD (n = 10). DPVA have been recorded only in patients with CHD (n = 50) (all patients having undergone ventriculography and coronarography). The prevalence of DPVA is 12.5% without VT/VF, 50% with VT/VF, and 80% when these arrhythmias are associated with the presence of a ventricular aneurysm. The duration of the DPVA is also important, since it is only in the group with VT/VF and with aneurysm that the R-EVEA duration (interval between the peak of the R wave and the end of electrical ventricular activity) exceeds 100 ms. DPVA disappeared in all the cases after aneurysmectomy. The DPVA, when of long duration, can be considered a hallmark of serious ventricular arrhythmias in patients with CHD and a ventricular aneurysm.

Action Potentials↗
PubMed1983

The effects of kindling on GABA-mediated inhibition in the dentate gyrus of the rat. I. Paired-pulse depression.

Double-pulse stimulation of the perforant path input to the dentate gyrus was used in the following experiments to produce paired pulse depression in that site. This effect provided an estimate of GABA-mediated recurrent inhibition. The depression was enhanced by drugs that facilitate or mimic GABA action and attenuated by drugs which block GABA transmission. Paired-pulse depression was significantly increased following amygdala kindling and was further enhanced to near maximal levels by subsequent kindling in the dentate. In addition, kindling did not increase the rate at which inhibition failed under conditions of excessive activation. Trains of 5 Hz stimulation, applied to the perforant path, caused paired-pulse depression to disappear and elicited a brief AD. Following kindling, the latency to AD onset tended to be increased rather than shortened, suggesting an enhanced resistance to inhibitory failure. These results indicated that kindling increased, rather than reduced, inhibition in the dentate gyrus.

Amygdala↗
PubMed1983

[Continuous electrocardiography monitoring during esophago-gastro-duodenoscopy].

Continuous ECG recording has been carried out during oesophagogastroduodenoscopy without premedication in 44 unselected patients. 8 of whom had cardiac diseases. Thirty-six had sinus tachycardia. Supraventricular and ventricular ectopic beats occurred in 11 patients, 5 of whom had cardiopathy. Two patients without known cardiac disease or rhythm disturbance developed a transient attack of paroxysmal atrial fibrillation. In both cases the fibrillation occurred against the background of a slow basal sinus rhythm which was considered to be the result of vagal stimulation. All arrhythmias were transient and symptom-free, but their occurrence poses problem of the indication for premedication before upper gastrointestinal endoscopy.

Adolescent↗
PubMed1983

[Evaluation of a method for ambulatory and automatic measurement of nyctohemeral arterial pressure].

This study was designed to evaluate a method of automatic non-invasive ambulatory blood pressure monitoring. Using a Del Mar Avionics Pressurometer II, we tested 12 normal subjects at rest and during exercise in our laboratory, and 12 patients with borderline hypertension during 24 hours of normal activity. At rest correlation coefficient of sequential measurements between pressurometer and a standard mercury sphygmomanometer were 0.96 for individual systolic measurements, 0.65 for individual diastolic measurements, and 0.99 for sequentially coupled diastolic or systolic measurements. The same correlation coefficients were found during a low level exercise test on cycloergometer (50 watts); at a higher level (75 watts), the correlation coefficient for systolic measurements is still high (0.93), whereas for diastolic measurements the correlation coefficient is low (0.45) in our experimental conditions. Fifty-eight non-invasive ambulatory recordings were obtained during normal daily activities. About 10% of the measurements were eliminated because of artefacts. We conclude that the nycthemeral fluctuations of the blood pressure can be reasonably estimated by the Del Mar Avionics Pressurometer II, but that such results can be obtained only if special attention is given to the positioning of the pressurometer on a motivated patient.

Adult↗
PubMed1982

Damaging effect of therapeutic radiation on programmable pacemakers.

Two series of present-day pacemakers were tested in vitro with pulsed x-ray radiation. The first series of 12 pacemakers consisted of 10 different types and models of demand pacemakers (VVI). The second series of 13 pacemakers had 9 different types and models of programmable pacemakers. Unlike the first series which showed only mild changes in frequency and pulse width, all but four of the programmable pacemakers presented sudden complete failure after different radiation doses. We conclude that direct pulse radiation at therapeutic levels of programmable pacemakers should be avoided.

Computers↗
PubMed1982

[Value of echocardiography in the diagnosis of Uhl's disease. Apropos of a case in an adult].

Uhl's anomaly, or paper thin right ventricle is a rare congenital malformation which may present with variable degrees of hypoplasia. The most severe forms are encountered in infants and children, but a less serious form occurs in adolescents and adults which, clinically. There are a number of echocardiographic features common to both diseases but paper-thin right ventricle may be distinguished by the finding of premature opening of the pulmonary value. The increased atrial contraction in these patients with right ventricles of reduced compliance is directly transmitted to the pulmonary artery, leading to end diastolic opening of the pulmonary value before tricuspid closure. The case presented underlines the value of M mode echocardiography in the diagnosis of Uhl's anomaly and in the differential diagnosis with Ebstein's anomaly.

Diagnosis, Differential↗
PubMed1982

[Spontaneous cardiac rhythm in patients wearing cardiac stimulators].

Cutaneous electrical stimulation allows inhibition of permanent on-demand cardiac pacemakers. The evolution of the spontaneous cardiac rhythm was studied, using this technique of inhibition in 164 patients paced for 4 to 16 years. At implantation, 117 patients (70 p. 100) had atrioventricular block, 45 patients (27 p. 100) had sinoatrial dysfunction and 2 patients had a carotid sinus syndrome. Of these 164 patients, 153 were symptomatic. Three groups were distinguished: - 41 patients (25 p. 100) with a spontaneous ventricular rhythm at each check-up; - 75 patients (46 p. 100) with an underlying ventricular rhythm recorded when the pacemaker was inhibited by cutaneous electrical stimulation; - 48 patients (29 p. 100) with no underlying ventricular rhythm during 3 successive inhibitions of their pacemakers of 3 to 4 seconds duration on each occasion. All these patients had atrioventricular block at implantation; none had sinoatrial disease. In conclusion, disease of the atrioventricular conduction pathway, contrary to sinoatrial disease, leads to a prolonged absence of the spontaneous ventricular activity. This seems to be related to a longer survival of patients without associated pathology, and also suggests a degenerative cause of the atrioventricular block.

Adult↗
PubMed1980

[Pseudo Q waves in myocardial necrosis: a pitfall with a Wolff-Parkinson-White appearance].

The diagnosis of inferior myocardial infarction was wrongly made in a patient with a history of chest pain and Q waves in Leads 3 and aVF. Despite a normal PR interval, ventricular preexcitation was suspected on the deformation of the upstroke of the QRS complex, suggestive of a delta wave. Ventricular and coronary angiography and exercise Thallium 201 myocardial scintigraphy allowed the diagnosis of myocardial infarction to be eliminated. Endocavitary electrophysiological recordings confirmed the presence of an accessory atrioventricular conduction pathway (Kent bundle) and explained the intermittent appearances of the WPW syndrome on ECG. The patient was investigated after the acute episode, and the absence of cardiac enzyme estimations at that time made the rectification of the diagnosis more difficult.

Adult↗