Stepwise transvenous lead extraction due to pacemaker pocket infection following lactational mastitis complicated with breast abscess

BACKGROUND

Lactational mastitis is a common painful and debilitating inflammation of breast tissue, generally treated conservatively or with pus puncture in case of breast abscess. However, treating mastitis in patients with implantable surgical material located in the affected breast region can be extremely challenging. We present an unusual case of lactational mastitis complicated by pacemaker pocket infection in a breastfeeding mother.

CASE PRESENTATION

A 35-year-old pacemaker-dependent female developed lactational mastitis seven weeks postpartum. Initially, the condition was treated conservatively with analgesics and antibiotics. After abscess formation, pus was aspirated using fine-needle aspiration technique. Four weeks after mastitis resolution, pacemaker pocket infection developed. According to current cardiovascular implantable electronic device infection treatment guidelines a complete surgical extraction of the entire electronic system, followed by targeted antibiotic treatment and reimplantation of a new device after infection resolution, was recommended. However, after thorough discussion with the young woman and her family and after detailed review of surgery-related risks, she declined a potentially high-risk surgical procedure. Thus, only the pulse generator was explanted; pacing leads positioned in the sub-pectoral pocket; new pacemaker implanted on the contralateral side and broad-spectrum antibiotic therapy continued for six weeks. After breastfeeding cessation, and with chronic fistula development at the primary pacemaker implantation site, the possibility of delayed surgical intervention including complete extraction of retained pacemaker leads was again thoroughly discussed with her. After thoughtful consideration the woman consented to the proposed treatment strategy. A surgical procedure including transvenous lead extraction through the primary implantation venous entry site, using hand-powered bidirectional rotational sheaths, was successfully performed, removing all retained leads through the left subclavian venous entry site, and leaving the fully functional and clinically uninfected pacemaker on the contralateral site intact.

CONCLUSION

Although patients' decisions for delayed extraction in a case of cardiovascular implantable electronic device infection should be discouraged by attending physicians and members of interdisciplinary teams, our case shows that a stepwise treatment strategy may be successful as a bailout clinical scenario in patients with specific requests, demands and / or clinical needs.

Age and Gender Impact on Heart Rate Variability towards Noninvasive Glucose Measurement

Heart rate variability (HRV) parameters can reveal the performance of the autonomic nervous system and possibly estimate the type of its malfunction, such as that of detecting the blood glucose level. Therefore, we aim to find the impact of other factors on the proper calculation of HRV. In this paper, we research the relation between HRV and the age and gender of the patient to adjust the threshold correspondingly to the noninvasive glucose estimator that we are developing and improve its performance. While most of the literature research so far addresses healthy patients and only short- or long-term HRV, we apply a more holistic approach by including both healthy patients and patients with arrhythmia and different lengths of HRV measurements (short, middle, and long). The methods necessary to determine the correlation are (i) point biserial correlation, (ii) Pearson correlation, and (iii) Spearman rank correlation. We developed a mathematical model of a linear or monotonic dependence function and a machine learning and deep learning model, building a classification detector and level estimator. We used electrocardiogram (ECG) data from 4 different datasets consisting of 284 subjects. Age and gender influence HRV with a moderate correlation value of 0.58. This work elucidates the intricate interplay between individual input and output parameters compared with previous efforts, where correlations were found between HRV and blood glucose levels using deep learning techniques. It can successfully detect the influence of each input.

Relationship Between Azithromycin and Cardiovascular Outcomes in Unvaccinated Patients With COVID-19 and Preexisting Cardiovascular Disease

Background Empiric antimicrobial therapy with azithromycin is highly used in patients admitted to the hospital with COVID-19, despite prior research suggesting that azithromycin may be associated with increased risk of cardiovascular events. Methods and Results This study was conducted using data from the ISACS-COVID-19 (International Survey of Acute Coronavirus Syndromes-COVID-19) registry. Patients with a confirmed diagnosis of SARS-CoV-2 infection were eligible for inclusion. The study included 793 patients exposed to azithromycin within 24 hours from hospital admission and 2141 patients who received only standard care. The primary exposure was cardiovascular disease (CVD). Main outcome measures were 30-day mortality and acute heart failure (AHF). Among 2934 patients, 1066 (36.4%) had preexisting CVD. A total of 617 (21.0%) died, and 253 (8.6%) had AHF. Azithromycin therapy was consistently associated with an increased risk of AHF in patients with preexisting CVD (risk ratio [RR], 1.48 [95% CI, 1.06-2.06]). Receiving azithromycin versus standard care was not significantly associated with death (RR, 0.94 [95% CI, 0.69-1.28]). By contrast, we found significantly reduced odds of death (RR, 0.57 [95% CI, 0.42-0.79]) and no significant increase in AHF (RR, 1.23 [95% CI, 0.75-2.04]) in patients without prior CVD. The relative risks of death from the 2 subgroups were significantly different from each other (Pinteraction=0.01). Statistically significant association was observed between AHF and death (odds ratio, 2.28 [95% CI, 1.34-3.90]). Conclusions These findings suggest that azithromycin use in patients with COVID-19 and prior history of CVD is significantly associated with an increased risk of AHF and all-cause 30-day mortality. Registration URL: https://www.clinicaltrials.gov; Unique identifier: NCT05188612.

Association of the Polymorphism rs3918242 of the Matrix Metalloproteinase-9 Gene with Coronary Artery Disease in a Younger Population

Coronary artery disease (CAD) is a complex disease resulting from the interaction of numerous so-called traditional risk factors and comorbid conditions on the one side (such as dyslipidemia, smoking, obesity, diabetes, hypertension) and genetic factors on the other. The evidence of a genetic contribution to the development of CAD, especially in the last 2 decades is consistent. It is important that a number of established gene polymorphisms in the younger CAD population are in the genes involved in the inflammatory response and tissue maintenance and remodeling processes. The aim of this study is to investigate the association of the rs3918242 polymorphism of the matrix metal-loproteinase 9 (MMP9) gene with the coronary artery disease in the younger population. In this observational genetic-association study of cases and controls, the demographic, clinical, laboratory and genetic data of the younger population in a group of selected 70 CAD patients aged up to 45 years were analyzed, of which 35 patients have negative and 35 have positive coronary angiography finding, and 43 are men and 27 are women. The analysis of the genotypic and allelic frequency determined an association of the polymorphism and the occurrence of the positive coronary angiographic findings in the population of patients under the age of 45. The carriers of the heterozygous genotype CT have almost 5 times higher probability of having a positive coronary angiography finding compared to the carriers of the reference homozygous genotype CC (p=0.012). Thus, this parameter could be used for clinical risk assessment for the development of CAD.

Sex differences and disparities in cardiovascular outcomes of COVID-19

BACKGROUND

Previous analyses on sex differences in case fatality rates at population-level data had limited adjustment for key patient clinical characteristics thought to be associated with COVID-19 outcomes. We aimed to estimate the risk of specific organ dysfunctions and mortality in women and men.

METHODS AND RESULTS

This retrospective cross-sectional study included 17 hospitals within 5 European countries participating in the International Survey of Acute Coronavirus Syndromes (ISACS) COVID-19(NCT05188612). Participants were individuals hospitalized with positive SARS-CoV-2 from March 2020 to February 2022. Risk-adjusted ratios(RR) of in-hospital mortality, acute respiratory failure(ARF), acute heart failure(AHF), and acute kidney injury(AKI) were calculated for women versus men. Estimates were evaluated by inverse probability of weighting and logistic regression models. The overall care cohort included 4,499 patients with COVID-19 associated hospitalizations. Of these, 1,524(33.9%) were admitted to ICU, and 1,117(24.8%) died during hospitalization. Compared with men, women were less likely to be admitted to ICU (RR:0.80; 95%CI: 0.71-0.91). In general wards (GW) and ICU cohorts, the adjusted women-to-men RRs for in-hospital mortality were of 1.13(95%CI: 0.90-1.42) and 0.86(95%CI: 0.70-1.05; pinteraction=0.04). Development of AHF, AKI and ARF was associated with increased mortality risk (ORs: 2.27; 95%CI; 1.73-2.98,3.85; 95%CI:3.21-4.63 and 3.95; 95%CI:3.04-5.14, respectively). The adjusted RRs for AKI and ARF were comparable among women and men regardless of intensity of care. By contrast, female sex was associated with higher odds for AHF in GW, but not in ICU (RRs:1.25; 95%CI0.94-1.67 versus 0.83; 95%CI:0.59-1.16, pinteraction=0.04).

CONCLUSIONS

Women in GW were at increased risk of AHF and in-hospital mortality for COVID-19 compared with men. For patients receiving ICU care, fatal complications including AHF and mortality appeared to be independent of sex. Equitable access to COVID-19 ICU care is needed to minimize the unfavourable outcome of women presenting with COVID-19 related complications.

Cohort profile: the ESC EURObservational Research Programme Non-ST-segment elevation myocardial infraction (NSTEMI) Registry

AIMS

The European Society of Cardiology (ESC) EURObservational Research Programme (EORP) Non-ST-segment elevation myocardial infarction (NSTEMI) Registry aims to identify international patterns in NSTEMI management in clinical practice and outcomes against the 2015 ESC Guidelines for the management of acute coronary syndromes in patients presenting without ST-segment-elevation.

METHODS AND RESULTS

Consecutively hospitalised adult NSTEMI patients (n = 3620) were enrolled between 11 March 2019 and 6 March 2021, and individual patient data prospectively collected at 287 centres in 59 participating countries during a two-week enrolment period per centre. The registry collected data relating to baseline characteristics, major outcomes (in-hospital death, acute heart failure, cardiogenic shock, bleeding, stroke/transient ischaemic attack, and 30-day mortality) and guideline-recommended NSTEMI care interventions: electrocardiogram pre- or in-hospital, pre-hospitalization receipt of aspirin, echocardiography, coronary angiography, referral to cardiac rehabilitation, smoking cessation advice, dietary advice, and prescription on discharge of aspirin, P2Y12 inhibition, angiotensin converting enzyme inhibitor (ACEi)/angiotensin receptor blocker (ARB), beta-blocker, and statin.

CONCLUSION

The EORP NSTEMI Registry is an international, prospective registry of care and outcomes of patients treated for NSTEMI, which will provide unique insights into the contemporary management of hospitalised NSTEMI patients, compliance with ESC 2015 NSTEMI Guidelines, and identify potential barriers to optimal management of this common clinical presentation associated with significant morbidity and mortality.

Epidemiology and impact of frailty in patients with atrial fibrillation in Europe

BACKGROUND

Frailty is a medical syndrome characterised by reduced physiological reserve and increased vulnerability to stressors. Data regarding the relationship between frailty and atrial fibrillation (AF) are still inconsistent.

OBJECTIVES

We aim to perform a comprehensive evaluation of frailty in a large European cohort of AF patients.

METHODS

A 40-item frailty index (FI) was built according to the accumulation of deficits model in the AF patients enrolled in the ESC-EHRA EORP-AF General Long-Term Registry. Association of baseline characteristics, clinical management, quality of life, healthcare resources use and risk of outcomes with frailty was examined.

RESULTS

Among 10,177 patients [mean age (standard deviation) 69.0 (11.4) years, 4,103 (40.3%) females], 6,066 (59.6%) were pre-frail and 2,172 (21.3%) were frail, whereas only 1,939 (19.1%) were considered robust. Baseline thromboembolic and bleeding risks were independently associated with increasing FI. Frail patients with AF were less likely to be treated with oral anticoagulants (OACs) (odds ratio 0.70, 95% confidence interval 0.55-0.89), especially with non-vitamin K antagonist OACs and managed with a rhythm control strategy, compared with robust patients. Increasing frailty was associated with a higher risk for all outcomes examined, with a non-linear exponential relationship. The use of OAC was associated with a lower risk of outcomes, except in patients with very/extremely high frailty.

CONCLUSIONS

In this large cohort of AF patients, there was a high burden of frailty, influencing clinical management and risk of adverse outcomes. The clinical benefit of OAC is maintained in patients with high frailty, but not in very high/extremely frail ones.

Sex-related differences regarding cephalic vein lead access for CIEDs implantation

Background

Minimally invasive and safe central venous access is imperative for lead insertion of cardiac implantable electronic devices (CIEDs). The purpose of this trial was to explore and compare the usability of the cephalic vein (CV) between both sexes.

Methods and results

This single-center prospective study included 102 consecutive patients in a period of six months. Pre-procedural contrast-enhanced venographic images of the upper arm were performed in all included patients. Our attention was focused on comparing several morpho-anatomical CV characteristics such as venous diameter, presence of valves and angle of entrance of the CV into the subclavian vein (SV). Study results concerning the CV morpho-anatomical differences were more favorable regarding the female patient group, with significant differences in CV diameter (p-0.030). There was also a difference in favor of the female group regarding the favorable CV angle of entrance into the SV, found in the 61.7% versus 54.4% in the male patient group. The comparison of usability of the CV and CVC technique was explored by comparing the number of leads inserted through the CV in both sexes. Two leads were implanted in 11.7% in the female group versus 5.8% in the male group, and 0 leads through the CV in 38.2% of the female patients versus 50% of male group.

Conclusion

Female patients have more favorable cephalic vein morpho-anatomical futures and better usability for lead placement than male patients.

Comparison of 24 h ECG Holter Monitoring with Real-time Long-term ECG Monitoring System using ECGalert Software and Savvy Single-Lead Patch

AIM: The aim of the study was to show non-inferiority of the single-channel ECGalert system to the gold standard (ECG Holter) in the detection of arrhythmias over the total wear time of both devices. METHODS: A prospective study enrolled a total of 165 patients hospitalized at the University Clinic of Cardiology, who underwent simultaneous single-channel ECG recording with ECGAlert system and a conventional 24 h Holter monitor on the 1st day and continued ECGAlert monitoring for few more days, under assignment of the doctor or at the wish of the patient. RESULTS: A total of 165 patients were included in the study, 61.2% male, mean age of 58.4 ± 12.7 years. Mean duration of ECG Holter monitoring was 23.2 ± 0.5 h and mean duration of ECGalert/Savvy monitoring was 64.6 ± 31.2. During the first 24 h of simultaneous ECG monitoring with both methods, no statistically significant difference was found in arrhythmia detection. Over the total wear time of both devices, the ECGalert system detected significantly more AF episodes as compared to Holter (p < 0.000). ECGalert demonstrated significantly lower detection rate of false pauses (0.001). However, false detection of episodes of VT or AF was significantly higher in ECGalert system versus Holter (p < 0.000 and p < 0.000 respectively). Patients were more satisfied with ECGalert system, due to lesser interference in daily activities. CONCLUSION: The ECGalert system demonstrated superiority over traditional Holter monitoring in arrhythmia detection in the total monitoring period, but not in the first 24 h.

Myocardial Infarction in Systemic Lupus Erythematosus - the Sex-Specific Risk Profile

BACKGROUND

Accelerated atherosclerosis is widely present in patients with systemic lupus erythematosus.

OBJECTIVE

The aim of this review was to analyze the relationship between systemic lupus erythematosus and cardiovascular diseases, with the emphasis on acute myocardial infarction.

METHODS

We conducted a literature review through PubMed and Cochrane, using keywords: SLE, atherosclerosis, atherothrombosis, coronary artery disease, myocardial infarction, prognosis, sex specifics.

RESULTS

Various molecular mechanisms triggered by infection/inflammation are responsible for endothelial dysfunction and the development of atherosclerosis at an earlier age. A contributing factor is the cumulative effect of traditional cardiovascular risk factors interaction with disease-related characteristics. Myocardial infarction rates are 2- to 10-fold higher compared to the general population. Young women have the highest relative risk, however, men carry at least 3-fold higher risk than women. Coronary involvement varies from normal coronary artery with thrombosis, coronary microartery vasculitis, coronary arteritis, and coronary atherosclerosis. Typical clinical presentation is observed in men and older women, while atypical is more frequent in young women. Treatment is guided by the underlying mechanism, engaging invasive procedures alone, or accompanied with immunosuppressive and/or anti-inflammatory therapy. There are significant gender differences in pathophysiology and clinical presentation. However, they receive the same therapeutic treatments.

CONCLUSION

Systemic lupus erythematosus is a major contributor to atherosclerotic and non-atherosclerotic mechanisms involved in the development of myocardial infarction, which should be taken into account during therapeutic treatment. Although systemic lupus erythematosus per se is a "female" disease, males are at increased cardiovascular risk and worse outcomes.

Chloroquine and Hydroxychloroquine in Treatment of Coronavirus Disease-19

At present, we are facing coronavirus disease (COVID)-19 pandemic caused by the severe acute respiratory syndrome coronavirus-2 with several treatment choices and reports of different treatment outcomes. Chloroquine and hydroxychloroquine use for the management of severely ill patients started as a quite enthusiastic treatment option, following several small clinical trials, case series reports, public authorities, and media affirmation. However, the evidence we have so far is conflicting and some national societies and professional institutions implicate that we should wait for definite treatment recommendations until there are solid data for or against the use of these drugs. Until we have more powerful evidence in our hands, we should be aware of safety issues of the old drugs for the new application in the emergency state we are facing today with the COVID-19 pandemic. We performed a concise review of strengths, limitations, and awareness for chloroquine and hydroxychloroquine use for COVID-19 infection treatment based on the evidence the science has today.

Coronavirus Disease-19 and Cardiovascular Disease

 We are facing serious coronavirus disease-19 pandemic, caused by the severe acute respiratory syndrome coronavirus-2. Among infected individuals, there is a higher prevalence of the cardiovascular disease, which leads to their poor prognosis. Myocardial injury is present in more than 15% of critical ill patients in the form of acute myocardial dysfunction or subsequent myocardial injury that develops as disease severity. This new virus pandemic is a global challenge for health-care system which was we still have much to learn.

Scoring System Assessment of Cephalic Vein Access for Device Implantation

The purpose of this study was to explore the usability of the cephalic vein (CV) for cardiac implantable electronic device (CIED) lead access by applying a scoring system to assess the venous anatomy. This prospective, single-center study included 100 consecutive patients who underwent CIED implantation within a period of one year. Contrast-enhanced venography images were obtained for every patient, focused on the CV, "T-junction," and the subclavian/axillary veins (SV/AVs). Though careful examination of the images, an angle, valves, diameter, noncollateral (AVDnC) score was constructed and used to aid in choosing a CV or SV/AV access approach; in all cases, however, the preferred approach was CV independent of the AVDnC score result obtained. Upon use of the scoring system, the majority of patients (54%) had type A score result (≥ 3), indicating a favorable anatomy for CV access. In 48 of these patients, the CV was used for the implantation of at least one lead. The remaining 46 (46%) patients had type B score result (≤ 2). In 41 patients from this group, SV/AV access was used for lead implantation and, in five patients, CV access was used. The number of leads introduced through the CV was associated with larger score and the operator's experience. In conclusion, in more than 50% of patients, at least one lead could be introduced through the CV. The scoring system used herein can simplify the choice between CV and SV/AV access and could eventually increase the efficiency and safety of the procedure, especially when less experienced implanters are involved.

Electrocardiographic Parameters as Predictors of Response to Cardiac Resynchronization Therapy

INTRODUCTION:

Although strict selection criteria are used to select patients for cardiac resynchronisation therapy, up to 30% of patients do not have a positive clinical response.

PATIENTS:

A total of 102 consecutive patients who had biventricular pacemaker/defibrillator (CRT-P or CRT-D) implanted were enrolled in this prospective observational study.

RESULTS:

During the average follow-up period of 24.3 months 5 patients died and 17 (16.7%) patients were hospitalised with the symptoms of heart failure; 75 (73.5%) patients were responders based on the previously defined criteria. Responders in the group of LBBB patients kept the significant difference in a computed variable (S1 + R6) - (S6 + R1) and R6/S6 ratio. Responders in non-LBBB patients kept the significant difference only in the height of R waves in V6. The R6/S6 ratio tended to be higher, but it did not reach a statistical significance.

CONCLUSION:

None of the tested ECG parameters stands out as an independent predictor of response to cardiac resynchronisation therapy, but some of them were different in responder-compared to the non-responder group. The amplitude of R wave in V6, higher R/S ratio in V6 and higher computed variable (S1 + R6) - (S6 + R1) may predict the likelihood of response to CRT therapy in both LBBB-patients and non-LBBB patients.

Anticoagulation Management in Patients with Pacemaker-Detected Atrial Fibrillation

INTRODUCTION:

In patients with an implanted pacemaker, asymptomatic atrial fibrillation (AF) is associated with an increased risk of thrombo-embolic complications. There is still no consensus which duration of episodes of atrial fibrillation should be taken as an indicator for inclusion of oral anticoagulation therapy (OAC).

MATERIAL AND METHODS:

A total of 104 patients who had no AF episodes in the past and have an indication for permanent pacing were included in the study.

RESULTS:

During an average follow-up of 18 months, 33 of the patients developed episodes of AF. Inclusion of OAC was performed in 17 patients, in whom AF was recorded, although in all patients CHA2DS2-VASc score was ≥ 1. The inclusion of OAC showed a statistically significant correlation with increasing duration of episodes of AF (r = 0.502, p = 0.003). During the follow-up period none of the patients developed thrombo-embolic complication.

CONCLUSION:

Considering that our group of patients had no thrombo-embolic events, we could conclude that dividing the AF episodes in less than 1% in 24 hours and longer than 1% within 24 hours could be an indicator for decision-making to include OAK if the CHA2DS2-VASc score is ≥ 1.

Cardiac memory (t-wave memory) after ablation of posteroseptal accessory pathway

BACKGROUND

Cardiac memory is a phenomenon characterized by transient T-wave abnormalities occurring during normal sinus rhythm, after a period of altered ventricular depolarization, where the T-wave vector has the same direction as the vector of the previously altered QRS complex (T-wave inversion). It is a form of electrical remodelling of the ventricular, where the T-wave follows ("remembers") a previously altered QRS vector.

METHODS AND RESULTS

Over a 5-year period (2002-2006), 525 consecutive patients underwent electrophysiological study. One hundred and one patients underwent ablation of the atrioventricular reentry tachycardia (AVRT) with an accessory pathway (AP). Forty-two of them were without delta wave on the electrocardiogram (concealed accessory pathway), and 58 patients had an open form of accessory pathways, with delta wave on EKG (Wolff-Parkinson-White syndrome) and only one patient had an accessory pathway between the right atrium and right bundle branch (Mahaim form). According to the location of the accessory pathway, 17 patients (29.3 %) had an accessory pathway in the right posteroseptal region. There was the highest percentage of the appearance of inversion of the T-wave in patients with this position of accessory pathway. T-wave changes were followed in the frontal plane (leads II, III, and aVF). Electrocardiogram (ECG) signs of cardiac memory were present in 16 of 17 (94.1 %) patients within one day after the ablation. The post-ablation T-wave vector had the same direction as the vector of the pre-excited QRS complex (and delta wave) creating inferior T-wave inversions. There was no correlation between the number or duration of energy applications and the extent of cardiac memory post ablation. A majority (90% of cases) of ECGs recorded 3 months after the procedure showed complete or almost complete normalization. None of the patients with T-wave inversion after ablation had a recurrence of preexcitation or tachycardia during the follow-up period of 12 +/- 4 months.

CONCLUSIONS

T-wave inversion in leads II, III and aVF with the disappearance of the delta wave after ablation of the accessory pathway in patients with Wolff-Parkinson-White syndrome (accessory pathway in the right posteroseptal region of the heart), is the most powerful marker of successful ablation.

Radiofrequency current catheter ablation of accessory atrioventricular pathways

BACKGROUND

The purpose of this study was to evaluate the safety and efficacy of a radiofrequency catheter ablation in the patients with the Wolff-Parkinson-White syndrome or paroxysmal supraventricular tachycardia involving a concealed accessory atrio ventricular connection.

METHODS AND RESULTS

During a 45 month period (1st January 2002 until 30th September 2005) 373 consecutive patients underwent electrophysiological study in our electrophysiological lab at the Institute for Heart Diseases. Of all the patients 171 (45.8%) were ablated for junction depend tachycardia. Ninety-five patients had undergone ablation of atrioventricular nodal reentrant tachycardia (AVNRT), atrioventricular reentry tachycardia (AVRT) with accessory pathway (AP) 76 patients. Ablation of the atrioventricular node (AVN) was performed in 59 patients, because of uncontrolled atrial fibrillation with implantation of pacemakers. Ablation was successful in 206 patients (89.3%), partial successful was achieved in 21 patient (9.4%), and no successful only in 3 patients (1.3%). Ablation successful outcome rate was 98.7% (without clinical supraventricular arrhythmia in the follow up period until September 2005). There was a need for performing a re-do ablation in 11 patients (4.8%). A complication occurred in 8 patients, 4.9% (only one major complication, complete atrioventricular block with narrow QRS complex in the AVNRT group). In the group with accessory pathways (atrio ventricular reentry tachycardia (AVRT), there were 76 patients, 28 without delta way on the electrocardiogram (concealed accessory pathways), 47 patients were with open form of accessory pathways, with delta way on EKG (Wolff-Parkinson-White syndrome) and only in one patient with accessory pathway between right atrio and right bundle branch (Mahaim form of concealed accessory pathway). In two patients with AVRT, another circle movement tachycardia was found after the ablation of the accessory pathways, bystander arrhythmia of AVNRT:

CONCLUSIONS

The success and safety of catheter accessory pathway ablation is so great that we recommend this nonpharmacological approach as an initial option to any patient with AVRT who has recurrent symptomatic arrhythmias.

Induction of atrioventricular node reentry by simultaneous anterograde conduction over the fast and slow pathways

Atrio-ventricular node reentry (AVNRT) is typically induced with an anterograde block over the fast pathway (FP) and conduction over the slow pathway (SP), with subsequent retrograde conduction over the FP. Rarely, a premature atrial complex (PAC) conducts simultaneously over the FP and SP to induce AVNRT. Previous publications have reported that conduction over the fast and slow pathway of the atrioventricular node can occur successively one after the other, thus leading to dual ventricular depolarization from what initially was a single atrial impulse. We report a case of an 18-year-old male patient referred for repeated bursts of ectopic activity. Evaluation of the patient's electrocardiographic recordings suggested the presence of dual ventricular activations for each atrial beat. The electrophysiological study revealed that the patient had simultaneous conduction over the fast and slow pathways of the atrioventricular node giving rise to a non-reentrant tachycardia, along with an absence of retrograde (ventriculoatrial) conduction, and a significant atrio-His bundle jump (A-H jump) through the slow pathway from the fast pathway during programmed electrical stimulation from the right atrium. Ablation of the slow pathway at the base of the Koch triangle yielded a cessation of the dual ventricular response, absence of the nonreentrant tachycardia and no A-H jump.