Maciej Wielusiński

The effect of atrial pacing site on electrophysiological properties of the atrioventricular junction and induction of atrioventricular nodal reentry in patients with typical atrioventricular nodal reentrant tachycardia

BACKGROUND Clinical studies in humans have shown the site of atrial stimulation to influence atrioventricular (AV) conduction times and refractory periods, the demonstration of dual AV nodal (AVN) pathways, and induction of AVN reentry. These studies often found conflicting results. Moreover, among enrolled patients a minority of them were found to have AVN reentrant tachycardia (AVNRT). AIM The purpose of this study was to investigate the effect of right and left atrial pacing on the electrophysiological properties of the AV junction in the typical AVNRT population. METHODS Ninety-two consecutive patients with typical AVNRT were included. Atrial pacing was performed from the high right atrium (HRA) and the left atrium via the proximal coronary sinus (CS). RESULTS Stimulation from either the HRA or the CS could result in dual AVN physiology and AVNRT. No site-dependent differences in the ease of induction of dual AVN pathways with variability of initiation from either site were found. However, AVNRT was easier to induce from the HRA. With CS pacing the leftward but not the rightward AVN approaches were the entry point to the AV node because of significantly shorter AH conduction times compared to HRA pacing. Conduction over the leftward AVN extensions could initiate the tachycardia with significantly shorter critical AH interval compared to conduction over the rightward AVN extensions; however, the AH interval during AVNRT and its cycle length were not significantly different. CONCLUSIONS Rightward and leftward AVN extensions are regular features of the AV node. Their different electrophysiological properties lead to variation in the demonstration of discontinuous AVN conduction and AVNRT during right and left atrial pacing. Despite the observation that the left AVN extensions could compose the entry point to the reentrant circuit, there is no evidence that they constitute the critical component of sustained typical AVNRT.

Śluzak prawego przedsionka u pacjenta z twardziną układową

The myxoma makes 80–90% of benign cardiac neoplasms. The first symptom in 50% of patients is an embolism resulting from relocation of tumor fragments or blood clots into the bloodstream. Elevated values of acute phase proteins in these patients are results of non-specific immune response to an antigen causing the disease. Interleukin 6 (IL-6) plays a role in this reaction, modifying inflammatory response by: influence on lymphocyte T differentiation, lymphocyte B to plasmocyte transformation, and stimulation of the liver to produce acute phase proteins. Elevated IL-6 is found in 80% of patients with diagnosed myxoma, which causes it to be an important marker in diagnostic and post-operational monitoring. The role in non-specific inflammatory response played by IL-6 in myxoma and autoimmune disorders was a cause of many diagnostic mistakes. Available literature does not suggest a coincidence of cardiac myxoma and systemic sclerosis. This is why we would like to present a case report, with special regard to correlation between IL-6 values and activity/stage of diagnosed disorders.

Ocena przebiegu klinicznego i czynników wpływających na historię naturalną typowego częstoskurczu węzłowego nawrotnego

Introduction. Atrioventricular nodal reentrant tachycardia (AVNRT) is the most common regular tachyarrhythmia; however, its clinical presentation has not been investigated in detail. The aim of the study was to assess the clinical presentation and identify the potential factors significantly affecting the natural history of AVNRT in patients undergoing RF ablation. Material and methods. Ninety-two consecutive patients with invasive diagnosis of typical AVNRT who underwent RF ablation were included. All patients were actively screened for the presence of structural heart disease (SHD). The retrospective, arrhythmia focused interviews regarding its clinical history, affecting factors and treatment were conducted. The medical records and tachycardia ECG tracings data were included, if available. Results. Seventy-five percent of patients had evidence of the arrhythmia exacerbation. No relationship between the coronary (66%) or brain (33%) hypoperfusion symptoms and clinical factors was found. Time to the tachycardia diagnosis was significantly longer in women (13 ± 11 vs 7 ± 8 years, p = 0.006). Pharmacological AVNRT management was not consistent with the ESC guidelines. The arrhythmia symptoms were occurring later if SHD was present (44 ± 13 vs 30 ± 5 years, p = 0.001). The longer AVNRT cycle length (CL), modified by the age when symptoms appeared and the presence of impaired myocardial contractility, the longer time to the arrhythmia diagnosis and exacerbation. Mitral valve prolapse (MVP) was more common in female patients compared with the general population and was found to be the factor delaying AVNRT diagnosis. Conclusions. In the majority of patients AVNRT exacerbation takes place. The coronary and brain hypoperfusion symptoms that patients often experience are nonspecific. There is a significant delay in the arrhythmia diagnosis, especially in women. SHD, AVNRT CL and MVP were identified as factors that significantly modify the arrhythmia clinical presentation.

Ocena EKG i parametrów holterowskich u pacjentów z zapaleniem wielomięśniowym i skórno-mięśniowym

Introduction. The aim of our study was to determine the electrocardiography (ECG) and holter abnormalities among patients with dermatomyositis (DM) or polymyositis (PM). Material and methods. We examined 19 patients with PM and 11 patients with DM (23 females) and 30 healthy subjects (22 females). Mean disease duration was 6.5 ± 4.7 years. ECG parameters (QRS, PQ, P wave, conduction disturbances) and heart rate variability data, QT/QTc, ventricular extra beats, creatine kinase, aldolase and lactate dehydrogenase activities were assessed. Results. We did not observe any statistically significant differences in parameters assessing the autonomic system function, the QT/QTc, ventricular rhythm disorders. Intraventricular conduction disturbances were observed in 16.6% of patients with PM/DM. Finally, there were significant differences when comparing enzyme activities. Higher enzyme activities in DM/PM did not correlate with the diurnal variability of cardiac rhythm. Conclusions. This suggests no tendency of DM and PM to involve the autonomic nervous system. Conduction disturbances in DM and PM affect mainly the His-Purkinje system.

Cryoballoon ablation of paroxysmal atrial fibrillation and underlying atrial tachycardia and ectopy arising from a common trigger focus limited to a right inferior pulmonary vein

A 69-year-old woman (case 1) and a 36-year-old man (case 2) without comorbidities, normal pulmonary veins (PV) anatomy and atrial, mitral, PV dimensions were referred for cryoballoon ablation of paroxysmal atrial fibrillation (AF). Although atrial tachycardia (AT) and a frequent atrial ectopy (AE) had never been documented, ongoing AT or AE mimicking sinus rhythm (SR) were noticed at admission. An electrophysiological study, in a drug free state, with catheters placed into the coronary sinus, in the right atrium (RA) and His bundle was performed. The positive P wave in lead V1, superimposed on the negative T wave and the negative P wave in lead aVL in case 1 (Figs. 1A, B), and similarities in the P wave morphology during AE and SR and negative P waves in lead aVL in case 2 (Figs. 2A–C), suggested PV AT/AE. Activation mapping with a circular catheter within each PV was performed. Right inferior PV (RIPV) depolarisation preceded the onset of the ectopic P wave by 60 ms (Fig. 1A) and 50 ms (Fig. 2B), respectively. During cryoapplication with a 28 mm cryoballoon catheter (Fig. 3), SR was restored (Figs. 1B, 2C). We did not notice PV electrical activity within other PVs during AT/AE and SR. Although a single culprit PV was found, isolation of the remaining PVs was performed. Post-ablation, there was a bidirectional block within all PVs and no AT/AF was induced. No recurrences of any atrial arrhythmias were seen during the 18 month drug free post ablation follow-up. Focal AT/AE is a rare arrhythmia mainly arising from the RA (83%). The most frequent foci within the left atrium (LA) are superior PV ostia. Their origin from RIPV and coexisting AF with a trigger limited to the same PV, while it is commonly associated with multiple triggers from multiple veins (94%), is uncommon. Although AT and AF may be initiated by PV triggers, it is unclear whether in the presented cases there were two independent arrhythmogenic foci within one PV or a single AT/AE focus that resulted in a long-term AF. Many authors have suggested that PV AT and PV AF represent distinct entities. PV foci initiating AF have been identified to be located deep within the PV, in contrast to a more ostial location for AT. PV AT patients have a discrete, in contrast to diffuse, process involving PVs and the LA seen in AF. In PV AT patients without a history of AF following a focal ablation, AF episodes have not been documented during long-term follow-up. A single documented episode of a PV AT/AE indicates that the supposed previous episodes were short lasting and self-terminating, or just initiated AF.