[Non-invasive programmed transthoracic ventricular stimulation]. / Neinvazívní programovaná transtorakální stimulace komor.

In 10 healthy volunteers programmed transthoracic stimulation of the ventricles was performed using two commercially available non-invasive pacemakers. The connection of the oesophageal stimulator SP-5 with the transthoracic ventricular stimulator NP-4D made it possible to obtain a two-lead ECG tracing without artefacts. The quality of the obtained tracings (surface tracing and oesophageal tracing) made it possible to assess accurately the ventriculo-atrial conduction. The examinations performed indicate the practical use of combined oesophageal and transthoracic stimulation during non-invasive diagnosis.

[A new multipolar transesophageal electrode for assessment of activation sequence in the left atrium]. / Nowa, wielobiegunowa elektroda przelykowa do badania sekwencji pobudzenia lewego przedsionka.

A new multipolar transoesophageal electrode is described. Two patients were analysed. One with recurrent coronary sinus rhythm and the other with concealed WPW syndrome. Obtained recordings showed difference of sequence of left atrial depolarisation during recovery of the sinus rhythm after its overdrive suppression and during provoked tachycardia. Results are very promising and require further investigation.

[Comparison of the properties of spot and ring electrodes in transesophageal cardiac pacing]. / Srovnání vlastností bodové a prstencové elektrody pri jícnové kardiostimulaci.

The authors compare diagnostic oesophageal pacing of the left atrium by a ring and spot electrode using poles with an area of 20 mm2 oriented towards the left atrium. The examination was made in 15 volunteers, aged 37 +/- 5 years (range 28-43 years). In different depths of the oesophagus the threshold of stimulation was assessed (PS) and the threshold of perception of stimulation (PV) of the left atrium. At each of the examined levels the amplitude of waves A and V was determined as well as the A/V ratio. The change from a ring to a spot electrode reduces the PS from 12.2 +/- 2:3 (8.0-15.0 O) mA to 8.0 +/- 1.3 (6.0-10.0) mA. When the spot electrode is used, the difference between PS and PV is markedly reduced; one third of the examined subjects can be stimulated without subjective perception. The amplitude of the A wave recorded by means of the spot electrode was not reduced, as compared with the ring electrode and the optimal A/V ratio above 2:1 was recorded by the spot electrode on a longer section of the oesophagus. Evidence was also provided that the lowest PS is 3-4 cm beneath the site of recording of the maximum amplitude of wave A.

[Programmed noninvasive stimulation of the heart ventricle transcutaneously]. / Programowana nieinwazyjna stymulacja komór serca droga przezskórna.

Possibility of performing of a programmed transcutaneous heart stimulation by combining two, easily purchasable noninvasive cardiac stimulators was examined in 4 healthy volunteers. Combining of a SP-5 transesophageal stimulator with a transcutaneous NP-4D stimulator made conduction of the programmed cardiac stimulation possible as well as two undisturbed ECG recordings. The quality of the obtained recordings (surface and transesophageal) made estimation of the retrograde AV conductivity possible. The performed examinations point out to a practical utility of the applied combination of transesophageal and transcutaneous stimulation-for conducting of noninvasive diagnostic heart examination.

[Esophageal stimulation of the heart: importance of the artifact inhibition system impulse in the quality of the ECG tracing from the stimulating electrode in the esophagus]. / Jícnová stimulace srdce: význam systému tlumení artefaktu stimulacního impulsu pro kvalitu EKG-záznamu z jícnové stimulacní elektrody.

The use of diagnostic possibilities of oesophageal stimulation of the heart depends on obtaining a readable and stable electrocardiogram from the stimulating electrode. The objective of the evaluating the importance of the electronic system eliminating the artefact of the stimulating impulse from the oesophageal tracing was to compare the quality of records obtained by the new and the traditional method. For stimulation an oesophageal cardiostimulator SP-5 manufactured by OBR, TEMED Zabrze was used. The atria and ventricles were stimulated by a fixed frequency and individual timed stimuli. In 58 subjects the tracings of the oesophageal ECG during stimulation of the atria were compared and in 45 subjects during oesophageal stimulation of the ventricles. The quality of the obtained tracings was evaluated by four grades where the first three grades include tracings not suitable for diagnostic interpretation. Contrary to the traditional method, the new method for obtaining tracings made it possible to obtain tracings the quality of which was in all instances suitable for interpretation. The assembled results provide evidence, due to the new system of recording, that there are great opportunities to extend diagnostic possibilities of oesophageal stimulation of the heart.

[Carotid sinus syndrome diagnosed by transcutaneous cardiac pacing]. / Zespól nadwrazliwej zatoki szyjnej diagnozowany przezskórna stymulacja serca.

The diagnostic usefulness and safety of non-invasive heart stimulation has been tested on 20 persons with full symptomatic cardiodepressive type of carotid sinus syndrome. The estimation of the cardiodepressive syndrome has been conducted on the grounds of electrophysiological tests of the heart with the method of endocavitary stimulation introduced by Stryjer and adopted by us for non-invasive heart stimulation. Massage of the carotid sinus was performed during sinus rhythm, during transesophageal atrial stimulation and during transcutaneous ventricle stimulation. In 17 persons massage of the carotid sinus caused sinus node inhibition. In this group carotid sinus massage during atrial stimulation revealed a group of 10 persons with only sinus node inhibition (type A) and a group of 7 persons with the coexistence of sinus node inhibition and an AV III block (type C). Only in 3 persons massage of the carotid sinus merely caused an AV III block (type B). Massage of the carotid sinus during transcutaneous ventricle stimulation showed retrograde AV conduction suppression in type B and C of the carotid cardiodepressive syndrome. To recapitulate the obtained results, it can be assumed that electrophysiological estimation of the carotid sinus syndrome is also possible and safe with the non-invasive method. Such procedure can also facilitate the selection of patients for permanent stimulation of AAI type for the type A syndrome or DVV for types B and C.

[Effect of propranolol on electrophysiologic features of the heart in patients with hyperthyroidism]. / Wplyw propranololu na wlasciwosci elektrofizjologiczne serca u chorych z nadczynnoscia tarczycy.

The effect of increasing doses of intravenously administered propranolol on electrophysiological features of heart was studied in 17 patients with untreated hyperthyroidism by using the transesophageal stimulation method. A positive and dose-dependent effect of propranolol on the studied parameters was found with the normalization of the majority of disturbances taking place after the administration of 6 mg of propranolol. This dose was safe and well tolerated by the patients. The sensitivity of the auriculo-ventricular junction to propranolol was less pronounced during the stimulated rhythm than during the sinus rhythm.

The effect of suppression of the distortion artifact during transcutaneous pacing on the shape of the QRS complex.

The quality of the ECG recording during transcutaneous pacing was evaluated in six healthy volunteers. The transcutaneous pacing stimulator was an NP4D special unit to which was attached an electronic suppressor of artifact generated by the transcutaneous stimulating impulse. The relationship between this suppression of artifact distortion and the resulting QRS complex was analyzed. The results revealed that the suppression time (described as a 2-mm oscillation from 100-Hz frequency) was required for ECG distortion elimination and that this is dependent on the threshold of ventricular pacing. The width of the resulting QRS complex diminishes as the suppression is extended over 110 ms. These results suggest the necessity of individual adjustment of the suppression time so that the efficacy of transcutaneous pacing is adequately assessed.

A method of esophageal electrogram recording for diagnostic atrial and ventricular pacing.

This study evaluates improvement of the electrogram sensed via an esophageal catheter with the sensing electrode adjacent to the stimulating electrode with and without a specialized artifact suppression system. In 100 patients (65 men and 35 women) aged 16-60 years (mean 48 years), esophageal recordings of left atrial activity were obtained during simultaneous transesophageal atrial pacing. Transesophageal ventricular pacing was performed in an additional 34 patients. Without the suppression system, ventricular paced activity, recorded from the esophagus, was not suitable for interpretation. About 10% of the atrial electrogram response could be recorded and evaluated during atrial pacing. With the stimulus artifact suppression system, interpretable recordings were obtained 100% of the time during atrial and ventricular recordings. The method described allows use of transesophageal diagnostic testing where previously only the intracardiac route was possible.

[Trans-esophageal stimulation of the heart: electrophysiological properties of the heart of healthy subjects IV]. / Stymulacja przezprzelykowa serca: wlasciwosci elektrofizjo- logiczne serca ludzi zdrowych. Czesc IV.

The aim of the study to compare left atrial and ventricular electrophysiological properties determined by transesophageal stimulation with those of right atrium and ventricle measured by other authors using transvenous cardiac stimulation. 45 healthy persons (13 females and 32 males) with average age 37 years underwent the study. Transesophageal pacemaker SP-5 made by TEMED and an universal diagnostic electrode for atrial as well as ventricular stimulation were used to obtain ++noise-free recordings. ECG was recorded by 6-channel Mingograph 61 (Simens-Elema) with a paper speed - 100 mm/s. Left atrial effective refractory period (ERP LA), left ventricular effective refractory period (ERP LV), ERP of a-v conduction system measured from atrium and ventricle (ERP AVCS A, ERP AVCS R) were determined basing on generally acceptable criteria. Parameters were measured during sinus rhythm as well as atrial and ventricular stimulation with a pacing cycle length of 700 and 500 ms. There were also determined maximal antero- and retrograde 1:1 conduction via a-v node and a-v conduction time in both directions during atrial and ventricular pacing with a cycle length of 600 ms. No retrograde a-v conduction was stated in 33% of patients. Shortening of left atrial and ventricular effective refractory periods was respective to shortening of pacing cycle length from 700 to 500 ms: ERPLA-256-245-235 ms, for ERPLV-278-248-241 ms for ERP AVCS A-301, 405, 360 ms and for ERP AVCS R during sinus rhythm-312 ms. Maximal anterograde 1:1 a-v conduction was 162/min and retrograde one 156/min.(ABSTRACT TRUNCATED AT 250 WORDS)

[Latent retrograde atrioventricular conduction in healthy persons]. / Utajone przewodzenie komorowo-przedsionkowe u osób zdrowych.

45 patients (13 females and 32 males; mean age-37 years) without an organic heart disease underwent the study, on condition that effective transesophageal, ventricular stimulation was achieved. The transesophageal pacemaker SP-5 made by OBR TEMED ZABRZE was used. Ventricular stimulation threshold and a lock of evident retrograde conduction was estimated during ventricular stimulation with a constant cycle length of 500 ms. To assess concealed retrograde atrioventricular conduction, programmed ventricular stimulation of a 50 ms cycle length was applied between late diastole and left ventricular refraction. Concealed retrograde atrioventricular conduction was diagnosed of a sinus impulse reached later ventricles than that during sinus rhythm preceding an examination. There was no evident atrioventricular retrograde conduction in 15 patients (33%). In 9 of them (60%) programmed stimulation revealed concealed retrograde atrioventricular conduction reaching atrioventricular node. Obtained results indicate, that the transesophageal programmed ventricular stimulation enables to examine concealed a-v conduction phenomenon and can be helpful in approximate localization of retrograde atrioventricular block.

[Supraventricular arrhythmia imitating ventricular ectopy due to simultaneous conduction in dual AV nodal pathways--a therapeutic problem]. / Podwójna odpowiedz komór imitujaca ektopie komorowa po jednoczesnym pobudzeniu szybkiej i wolnej drogi wezla p-k--jako problem terapeutyczny.

In 3 post-MI patients with multiple premature ventricular complexes, programmed transoesophageal pacing generated the arrhythmia and an ecg tracing was taken. Analysis of the ecg suggested that simultaneous activation of two pathways within the A-V node maybe the cause of the arrhythmia. The activation signal reaches the ventricle through both pathways but as the conduction time differs the ventricles can be twice activated. However the second activation is aberrantly conducted leading to an ecg picture of ventricular ectopy. Verapamil suppressed the arrhythmia which further indicates the non-ventricular origin of these wide QRS complexes.

[Transcutaneous stimulation of the heart ventricles: its effectiveness, comfort during the examination and new diagnostic possibility]. / Przezskórna stymulacja komór serca: skutecznosc, komfort badania i nowa mozliwosc diagnostyczna.

An attempt of assessment of transcutaneous cardiac pacing tolerance in healthy volunteers was carried out as well as abilities of this method utilization for examination of retrograde atrioventricular conduction. Ventricles were paced through highohm electrodes positioned on the chest wall with simultaneous recordings of transoesophageal ecg at the level of the left atrium and the sphygmogram of the right common corotid artery. Pacing perception threshold, skeletal muscle stimulation threshold, cardiac pacing threshold, algesic and myo-respiratory threshold of examination tolerance were estimated. Effective ventricular pacing within the range of stimulation tolerance was obtained in 10 of 15 patients (67%). Mean ventricular pacing threshold was higher than pacing perception and skeletal muscles stimulation thresholds (42 mA; 9.4 mA and 20.2 mA). Ventricular pacing threshold was lower than algesic and muscles thresholds of examination tolerance (60-70 mA) warranting relatively good tolerance of transcutaneous cardiac ventricular pacing. In 8 of 10 persons with effective ventricular stimulation retrograde a-v nodal conduction was stated which proved that transcutaneous cardiac ventricular stimulation can be used for noninvasive assessment of retrograde a-v nodal conduction.

[Cardiac trans-esophageal pacing: significance of systemic damping of artifacts from stimulating impulses for ECG trace recordings recorded from a pacing trans-esophageal electrode. III]. / Stymulacja przezprzelykowa serca: znaczenie ukladu tlumienia artefaktu impulsu stymulujacego dla jakosci zapiscu ekg ze stymulujacej elektrody przelykowej. Czesc III.

Utilization of diagnostic abilities of the cardiac trans-esophageal pacing is related to necessity of obtaining the readable and stable ecg tracing from a pacing electrode. For that reason to evaluate the value of an electronic artifact suppression circuit of a pacing impulse from oesophageal ecg recording authors compared quality of obtained recordings using a new method with a traditional one. Trans-esophageal cardiac pacemaker SP-5 made by OBR, Temed, Zabrze was used. Atria and ventricles were stimulated using a constant pacing cycle length and a single programmable impulse. In 58 persons ecg transoesophageal recordings were compared during atrial pacing, and in 45 during ventricular one. Quality of obtained ecg recordings was estimated using 4-degree scale of which first three degrees comprised recordings the esophageal pacing electrode by a traditional method were unfit for diagnostic interpretation. As opposed to the pacing electrode allowed to obtain recordings with quality of which was suitable for diagnostic interpretation in all patients. Obtained results indicate on, thanks to the new recording circuit, existence of conditions to substantial extension of diagnostic abilities of transoesophageal cardiac pacing.

[Effect of various beta-adrenolytic drugs on heart rate and changes in left-ventricular systolic time intervals in patients with hyperthyroidism and simple goiter]. / Wplyw róznych leków beta-adrenolitycznych na czestosc akcji serca i zachowanie sie podokresów skurczu lewej komory serca u chorych z nadczynnoscia tarczycy oraz wolem obojetnym.

The effects of a short-term application of various beta-adrenolytic drugs on heart rate and on the changes in subperiods of left ventricle contraction have been studied in 71 patients with untreated hyperthyroidism and in 72 patients with simple goiter. The following drugs were used: propranolol, metoprolol, atenolol, pindolol, nadolol and acebutolol. It was found that those betaadrenolytic drugs which have no sympathomimetic action cause a significant decrease in heart rate both in patients with hyperthyroidism and in those with simple goiter. The effect of these drugs on heart rate was not related to the changes in blood serum concentrations of thyroxine and triiodothyronine. None of the drugs tested influenced appreciably the contraction subperiods of left heart ventricle, both in the patients with hyperthyroidism and in those with simple goiter.