PubMed Health⌕ Search

Biomedical subjects

M Pleskot

Publications and source records attributed to M Pleskot.

At least 37 records · Page 2Linked to original sources
PubMed1991

[Significance of invasive electrophysiologic examination in the diagnosis of ventricular tachyarrhythmia in Wolff-Parkinson-White syndrome].

The authors assessed basic clinical and electrophysiological indicators (using invasive electrophysiological examination) in 15 patients (11 men and 4 women) with symptomatic Wolff-Parkinson-White syndrome. In 47% of the examined patients they detected artificial ventricular tachyarrhythmias during programmed ventricular stimulation. They found that there is a risk of the development of spontaneous ventricular tachyarrhythmias under the following conditions: 1. transfer of impulses from the atria with an increased excitability (in two patients), 2. in the ventricular heart muscle (in one patient). In general they proved a high risk (in 20%) in patients with ventricular fibrillations and ventricular tachycardias leading to sudden death.

Adolescent↗
PubMed1991

[Programmed ventricular stimulation in the evaluation of the clinical significance of premature ventricular contractions].

The authors subjected 34 patients (27 men and 7 women) to invasive electrophysiological examination. All patients had early ventricular contractions class 3-5 according to Lown which were recorded during ECG monitoring in bed or by Holter's system. A pathological excitability of the ventricular myocardium was found during programmed stimulation in 29% of the subjects. The excitability of the heart muscle was substantially enhanced by the incidence of ischaemic heart disease and reduced left ventricular function. The decreased frequency and severity of early ventricular contractions during bicycle ergometry, the absence of palpitations and syncopes increases the probability of normal excitability of the ventricular myocardium.

Adolescent↗
PubMed1991

[Arrhythmic syncope and invasive electrophysiologic heart function tests].

The authors submitted to electrophysiological examination a total of 100 patients (66 men and 34 women) with brief disorders of consciousness where they ruled out extracardiac causes of unconsciousness, impaired blood flow through the heart and the syndrome of s-a node dysfunction. Forty-three subjects had severe arrhythmias during ECG monitoring in bed or by Holter's system (20 subjects paroxysms of ventricular tachycardia, 14 subjects ventricular extrasystoles according to Lown class 3-5, six subjects had transient high-grade a-v blocks, three subjects had symptomatic paroxysms of supraventricular tachycardia). In 57 patients ECG monitoring did not reveal ectopic arrhythmias and high-grade a-v blocks. Invasive examination confirmed or diagnosed arrhythmic syncopes in 49% of the entire group of 100 patients. It assessed the arrhythmic cause of syncopes in 33% of 57 subjects without severe arrhythmias and in 70% of 43 subjects with severe arrhythmias detected during ECG monitoring.

Adolescent↗
PubMed1990

[Use of Doppler ultrasonography in the diagnosis of aortic coarctation].

Coarctation may be suspected on two-dimensional echocardiography upon notation of an apparent narrowing of the lumen of the aorta, but sometimes the picture is not clear. The purpose of this study was the assessment the detection of coarctation in children with associated defects and if pressure gradient through the obstruction could be accurately estimated from Doppler. Methods. The study included 45 children (38 with coarctation of aorta and 7 with recoarctation) between the ages of 3 days to 14 years. The diagnosis was confirmed by cardiac catheterization and angiocardiography. Doppler echocardiographic studies were performed in all patients before surgery and in 40 patients after surgery. Doppler examination were performed with the use of continuous-wave flow meter Kardiodop KD-84 (Sonopan) with estimation of maximal velocity with histograph Doma HSD-83 (Domar) or with the use of Ultramark 4 Ultrasound System (ATL). The pressure gradient across the stenosis was calculated by using modified Bernoulli equation, and was defined as the subtraction of the square of the maximal velocity x 4 the descending and ascending aorta. Arm and tight cuff sphygmomanometer measurements were performed at the rest. Pressure drop in the descending aorta was measured by sphygmomanometry in 19 children and by catheterization in 10 children. The results were compared with Doppler calculated pressure gradients. Results. The maximal velocity in descending aorta increased on the average to 3.6 +/- 1.2 m/s was recorded in 43 children. With increasing severity velocities were higher, and with severe obstruction a pressure drop across the coarctation may persist throughout diastole and continuous forward flow was seen.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed1990

[Application of doppler ultrasound in diagnosis of aortic and pulmonary valve stenosis].

120 children (58 boys, 62 girls) aged 2 days-12 years (mean 3.5 +/- 3 years) with pulmonary or aortic valve stenosis underwent the study. Diagnosis was proved by a cardiac catheterization and angiography. There were determinated maximal flow velocities and pressure gradients through stenosed valve using the doppler ultrasound method. Values were compared with those obtained from cardiac catheterization. There were no statistically significant differences between these two methods. Increased blood flow velocities through the aortic or pulmonary valves were stated in the examined group comparing with healthy individuals. Obtained results prove Doppler method usefulness in diagnosis of aortic and pulmonary valve stenosis. In pulmonary valvular and subvalvular stenosis the Doppler method is useful for estimation of outflow tract obstruction while in a extreme case a results can be incompetent.

Aortic Valve Stenosis↗
PubMed1990

[Electrophysiologic effects of orally administered amiodarone].

The authors made an invasive electrophysiological examination of the heart before and after administration of amiodarone by the oral route in 18 patients (15 men and 3 women). Amiodarone was administered in maintenance doses of 200 or 400 mg/day for 3 to 13 months (mean 4.7 months). Comparison of values revealed a significant protraction of R-R, P-Q and QRS intervals on the surface ECG. A-H and H-V intervals on the electrogram of the bundle of His as well as effective refractory periods of the ventricular myocardium were significantly protracted. During high-frequency stimulation of the atria the frequency at which an a-v block grade II type I develops declined. No significant changes developed in Q-Tc intervals on the surface ECG, the PA-A on the electrogram of the bundle of His and in the corrected recovery period of the s-a node.

Administration, Oral↗
PubMed1989

[Monitoring the effectiveness of amiodarone in the treatment of ventricular ectopic arrhythmias].

The authors included in their investigation a total of 18 patients (15 men and 3 women) with electric instability of the ventricular heart muscle during programmed stimulation of the ventricles. They administered amiodarone to the patients by the oral route, 200 or 400 mg per day for a period of 3 to 13 months. They compared the subjective symptomatology, the finding on monitoring of the ECG with the patient in bed or by means of Holter's system and the results of programmed stimulation of the ventricles before and after amiodarone administration. There was a marked decline in the frequency of subjective symptoms reported by the patients (above all syncopes disappeared completely) and there was a marked decline or complete disappearance of serious ventricular ectopic dysrhythmias. Amiodarone eliminated electric instability of the ventricles as proved by programmed stimulation of the ventricles completely in 39% and partly in 11% of the subjects.

Adult↗
PubMed1989

[Relation between the surface ECG and the bundle of His electrogram in 200 patients].

The relationship was assessed between different types of conduction disorders in surface ECG and pathological changes of intervals in electrograms of the His bundle during spontaneous cardiac action and during artificial right atrial stimulation in 200 patients (130 men, 70 women). For the detection of prognostically less favourable intra- and infraHisal conduction disorders it was found important to study the bundle of His electrographically in the following types of surface ECG: complete block of the right Tawara node with left posterior and left anterior hemiblock, complete block of the left Tawara node, left posterior hemiblock, atrio-ventricular block of the 1st degree (particularly when associated with intraventricular conduction disorder), IInd - degree atrio-ventricular block 2:1 (3:1), less so atrio-ventricular block of the IIIrd degree. Even apparently normal surface ECG can sometimes conceal major damage to the His-Purkinje system. Invasive electrophysiological tests are justified by the presence of syncopes or their equivalents due to unknown causes.

Adolescent↗
PubMed1989

[Sensitivity and specificity of programmed stimulation of the cardiac ventricles].

The authors used programmed pacing of the ventricles in a total of 55 subjects (41 men and 14 women). In a group of 36 patients with chronic relapsing ventricular tachycardias they assessed the sensitivity of this method as 83.3%. In 19 subjects without serious organic heart disease and without clinically confirmed tachyarrhythmias programmed pacing of the ventricles did not reveal diagnostic ventricular tachycardias. The specificity of the method was 100%. The highest detection rate of diagnostic ventricular tachycardias was obtained when four extrastimuli were applied during the sinus rhythm and 2-4 extrastimuli, using the basic stimulation rate of 100/min.

Adolescent↗