Focus on malignant ventricular premature contractions

Premature ventricular contractions (PVCs) are common. Although often benign, they can also be associated with increased morbidity and mortality. The aim of this review was to assess the risk evaluation of PVCs in patients with or without structural heart disease and discuss the management of this arrhythmia. Reports published in English were searched in PubMed with the following search terms: premature ventricular contraction, ectopic ventricular beat, ventricular extrasystole, antiarrhythmic drugs, ablation, ventricular arrhythmia, ventricular tachycardia, ventricular fibrillation and torsade de pointe. This analysis suggests that all patients with frequent PVCs should be assessed for PVC burden, symptom status and the presence of structural heart disease. PVCs in patients with structurally normal hearts was once considered a benign phenomenon. Uncommonly, PVCs may provoke life-threatening arrhythmias. Ventricular fibrillation is the initial mode of malignant rapid ventricular arrhythmias (MRVAs). Patients with malignant PVC and PVC burden >10% are at increased risk of MRVA in case of myocardial infarction and heart failure. MRVA is the primary cause of sudden cardiac death in patients with and without structural heart disease. Therapeutic options include medical therapy and catheter ablation, the latter more effective and potentially curable, particularly in patients with left ventricular dysfunction. The timely recognition and effective treatment of malignant PVCs in symptomatic patients with underling cardiomyopathy are mandatory to initiate early therapies before the occurrence of adverse clinical outcomes and to improve the long-term prognosis.

Clinical course of arrhythmogenic right ventricular cardiomyopathy with end-stage heart failure and outcome after heart transplantation

BACKGROUND

Few data exist on the characteristics and outcomes of patients with arrhythmogenic right ventricular cardiomyopathy and advanced heart failure who undergo heart transplantation.

AIM

To explore the pretransplant course and outcomes of patients with arrhythmogenic right ventricular cardiomyopathy after heart transplantation.

METHODS

This observational retrospective monocentric study included all consecutive patients with arrhythmogenic right ventricular cardiomyopathy who underwent heart transplantation during a 13-year period (2006-2019) at Pitié-Salpêtrière University Hospital (Paris).

RESULTS

A total of 23 patients with arrhythmogenic right ventricular cardiomyopathy underwent heart transplantation between 2006 and 2019. The median time from diagnosis to heart transplantation was 9 years, and the median age at transplantation was 50 years. At diagnosis, half of the patients had left ventricular dysfunction, 59% had extensive T-wave inversion and 43% had a history of sustained ventricular tachycardia. Only five patients were involved in intensive sport activity. Indications for heart transplantation were end-stage biventricular dysfunction in 13 patients, end-stage right ventricular heart failure in seven and electrical storm in three. Only three patients had pulmonary hypertension, and half of the patients had atrial arrhythmias. The survival rate 1 year after heart transplantation was 74% (95% confidence interval 53-88%). Eight patients experienced primary graft dysfunction needing extracorporeal membrane oxygenation.

CONCLUSIONS

Patients with arrhythmogenic right ventricular cardiomyopathy who eventually needed heart transplantation mostly exhibited extended disease with biventricular dysfunction at diagnosis. Intensive sport activity did not seem to be a major determinant. Advanced heart failure usually occurred late in the course of the disease. Primary graft dysfunction after heart transplantation was frequent, and should be anticipated. Additional data are needed to identify the optimal timing for heart transplantation and predictors of end-stage heart failure in patients with arrhythmogenic right ventricular cardiomyopathy.

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.

Safety and efficacy of flecainide associated with beta-blockers in arrhythmogenic right ventricular cardiomyopathy

AIMS

Arrhythmogenic right ventricular cardiomyopathy (ARVC) is an inherited cardiomyopathy associated with a high risk of ventricular arrhythmia (VA). Current guidelines recommend beta-blockers as first-line medical therapy and if ineffective, sotalol or amiodarone. We describe our experience, as a tertiary centre for ARVC, with the effectiveness and tolerance of flecainide in addition to beta-blockers to prevent VA in ARVC.

METHODS AND RESULTS

We retrospectively included 100 consecutive ARVC patients who received flecainide with beta-blockers between May 1999 and November 2017. Treatment persistence and related side effects were assessed, as was VA-free survival on treatment, 24-h Holter monitoring and programmed ventricular stimulation (PVS) off- and on-treatment. Tolerance was good, with 10% flecainide discontinuations (lack of efficacy in six, atrial fibrillation in one, and side effects in three). No Brugada-induced electrocardiography pattern on flecainide or haemodynamic impairment was reported. Premature ventricular contraction burden at 24-h Holter monitoring was significantly decreased under treatment [median 415 (interquartile range, IQR 97-730) vs. 2370 (1572-3400) at baseline, P < 0.0001, n = 46]. Among the 33 patients with PVS under treatment, PVS was positive in 40% on-treatment vs. 94% off-treatment (P < 0.001). During a median follow-up of 47 months (IQR 23-73), 22 patients presented sustained VA on treatment, corresponding to an event rate of 5% [95% confidence interval (CI) (0.6-9)] at 1 year and 25% [95% CI (14-35)] at 5 years under treatment. No patient died.

CONCLUSION

This study suggests that flecainide and beta-blockers association is complementary to implantable cardioverter-defibrillator and catheter ablation and is safe for treating persistent symptomatic VA in patients with ARVC.

Incidence, epidemiology, diagnosis and prognosis of atrio-oesophageal fistula following percutaneous catheter ablation: a French nationwide survey

AIMS

Rate, incidence, risk factors, and optimal management of atrio-oesophageal fistula (AOF) after catheter ablation for atrial fibrillation (AF) remain obscure.

METHODS AND RESULTS

All French centres performing AF ablation were identified and surveys were sent concerning the number of procedures, eventual cases of AOF, and characteristics of such cases. Eighty-two of the 103 centres (80%) performing AF ablation in France were included, with a total of 129 286 AF ablations since 2006 (93% of the whole procedures in France). Thirty-three AOF were reported (reported rate 0.026% per procedure) with a stable reported annual incidence despite the increasing number of procedures. Sensitivity of computed tomography (CT) scan for AOF was 81%. Mortality was 60%, significantly lower in case of surgical corrective therapy (31 vs. 93%, P = 0.001).

CONCLUSION

The reported rate of AOF after AF ablation in this nationwide survey was 0.026%, with a stable reported annual incidence over time. A normal CT scan does not rule out the diagnosis and should be repeated in case of suspicion. Prognosis remains poor with a mortality of 60% and crucially dependant of immediate surgical correction. No clear protective strategy has been proven effective.

External Validation of a Risk Prediction Model for Ventricular Arrhythmias in Arrhythmogenic Right Ventricular Cardiomyopathy

The new 5-year ventricular arrhythmia (VA) occurrence risk model is a major breakthrough for arrhythmia risk stratification in the challenging population of patients with arrhythmogenic right ventricular cardiomyopathy (ARVC). In the original study, the model resulted in a 20.6% reduction in implantable cardioverter-defibrillator (ICD) placement compared with the 2015 consensus, for the same protection level. However, only internal validation was performed, limiting generalisation. We externally validated the model in a European tertiary care cohort of 128 patients with ARVC with restrictive indications for primary prevention ICD placement. Overall, 74% were men, none had VA history, and a single patient had an ICD at baseline. Median age at diagnosis was 38 years (interquartile range [IQR] 28-50). During a median follow-up of 7.8 years (IQR 6.1-9.7), 15 patients (12%) experienced VA. The model provided good discrimination, with a C-index for 5-year VA risk prediction of 0.84 (95% confidence interval 0.74-0.93). However, the model led to an overestimation of the 5-year VA risk when applying thresholds < 50%. With a < 10% predicted risk, no patient showed VA. With a 7.5% predicted risk, the ICD:VA ratio was 6.3 vs 3.4 in the original study. The model still outperformed the 2015 International Task Force Consensus. Overall, in a relatively large European ARVC cohort with restrictive indications for ICD placement, the ARVC model for VA prediction successfully identified ARVC patients with VA during follow-up. Yet, our study underscores the need for careful threshold selection, considering the model's associated risk overestimation in low- to intermediate-risk patients.

First clinical experience with the wearable cardiac rhythm long-term monitoring cardioskin device

Background

There are only limited options for long-term cardiac monitoring devices readily available in clinical practice for outpatients. Holter monitoring devices are limited by the uncomfort of wires and patches, the small number of leads for analysis, the quality of recordings or the monitoring duration while insertable cardiac monitors are costly and exposed to potential local complication.

Purpose

To describe a single center experience with a novel wearable device for cardiac rhythm monitoring.

Methods

The Cardioskin™ system is a patch-free, wire-free, wearable device with rechargeable batteries that provides a high quality 15-lead electrocardiogram monitoring over 1 month (Figure 1). Data are sent using a mobile application downloaded in the patient smartphone to a central Corelab where they can be interpreted by an expert and/or the prescribing physician. An alarm signal is readily available within the Cardioskin™ device, to allow patients to indicate the presence of symptoms. In this single center retrospective registry, we provide a first report of the use of this novel device in real world practice, with indication and duration of cardiac monitoring left at the physicans “discretion”.

Results

From January 2019 to December 2019, the Cardioskin™ system was prescribed in 60 patients for an overall median duration of 26.5 (14–32) days. The mean age of the patients was 45±12.2 years and 24 (40%) were male. Indications for cardiac monitoring were post-Stroke, palpitation, syncope and cardiomyopathy assessment in 56%, 30%, 7% and 7% of the cases, respectively. A sustained (&gt;30 seconds) supraventricular tachycardia was detected in 4 cases, including one case of atrial fibrillation, two case of atrial tachycardia and on case of junctional tachycardia. Unsustained ventricular tachycardia and atrial fibrillation burst were detected in another 2 cases (Figure 1). There was no reported case of skin irritation by the Cardioskin™ system or abrupt interruption of the monitoring by the patients.

Conclusion

The Cardioskin™ system is a novel, discreet and comfortable cardiac rhythm wearable long-term monitoring device which can be used in clinical practice for broad diagnostic indications.

Figure 1. Cardioskin system

Funding Acknowledgement

Type of funding source: Public Institution(s). Main funding source(s): ACTION coeur

P1480French experience of SICD implantation

OnBehalf

GPUR

Introduction

The subcutaneous ICD prevents complications of transvenous leads. Its implantation needs a defibrillation test. Performing this test increases the time of procedures..

Purpose

The aim of our study is to describe the experience of subcutaneous ICD of Assitance Publique des Hopitaux de Paris (AP-HP).

Materials and Methods

In a retrospective cohort we included patients who were involved in subcutaneous ICD treatment at the 5 hospitals of AP-HP from December 2012 to April 2018.Analysis used the Kaplan-Meier method and the Mann-Whitney U test.

Results

162 patients were implanted. 76% of implantations were for secondary prevention before 2017, but only 49% after 2017. 126 (77%) tests were successful at first shock, 14 (8.6%) needed a second shock or more, 9 (5.5%) did not have a test. The shock impedance was significantly higher when the shock was not effective at the first test, 82 ohms CI 95% [68; 112] versus 66 ohms CI 95% [64; 70], p &lt;0.05. 6 patients died (3.7%). Late follow up showed 23 (10%) appropriate shocks and 24 inappropriate shocks (11%) mainly due to T wave oversensing (37.5%).

Conclusions

This is the first french experience of SICD implantation. Success of defibrillation test was lower than expected.

Caracteristics of implantation General anesthesia (%) 162 (100) Procedure time (min) Mean ± SD (median)Range 73± 24 (60)20-165 Cameron Health (%) Generator SQ-RX ® 1010 12 (7.4) Boston Scientific (%) Generator EMBLEM ® A209 100 (61.7) Generator EMBLEM ® A219 44 (27.2) VF time (sec) Mean ± SD (median)Range 16.5± 3.4(15)10-37 Shock Impedance (ohm) Mean ± SD (median) Range 72 ± 12.7 (68) 42-130 Success at 1st shock (%) 126 (77.7) Success at 2nd shock or more (%) 14 (8.6) No test performed (%) 12 (7.4) Implantation caracteristics and defibrillation testing. Impedance was significantly higher in patients without success at first shock : 82 ohms CI 95% [68 ;112] vs 66 ohms CI 95% [64 ;70], p &lt; 0.05.

Abstract Figure. Survival without inappropriate shock

Androgenic effects on ventricular repolarization: A translational study from the international pharmacovigilance database to iPSC-cardiomyocytes

BACKGROUND

Male hypogonadism, arising from a range of etiologies including androgen-deprivation therapies (ADTs), has been reported as a risk factor for acquired long-QT syndrome (aLQTS) and torsades de pointes (TdP). A full description of the clinical features of aLQTS associated with ADT and of underlying mechanisms is lacking.

METHODS

We searched the international pharmacovigilance database VigiBase for men (n=6 560 565 individual case safety reports) presenting with aLQTS, TdP, or sudden death associated with ADT. In cardiomyocytes derived from induced pluripotent stem cells from men, we studied electrophysiological effects of ADT and dihydrotestosterone.

RESULTS

Among subjects receiving ADT in VigiBase, we identified 184 cases of aLQTS (n=168) and/or TdP (n=68; 11% fatal), and 99 with sudden death. Of the 10 ADT drugs examined, 7 had a disproportional association (reporting odds ratio=1.4-4.7; P<0.05) with aLQTS, TdP, or sudden death. The minimum and median times to sudden death were 0.25 and 92 days, respectively. The androgen receptor antagonist enzalutamide was associated with more deaths (5430/31 896 [17%]; P<0.0001) than other ADT used for prostate cancer (4208/52 089 [8.1%]). In induced pluripotent stem cells, acute and chronic enzalutamide (25μM) significantly prolonged action potential durations (action potential duration at 90% when paced at 0.5Hz; 429.7±27.1 (control) versus 982.4±33.2 (acute, P<0.001) and 1062.3±28.9ms (chronic; P<0.001), and generated afterdepolarizations and/or triggered activity in drug-treated cells (11/20 acutely and 8/15 chronically). Enzalutamide acutely and chronically inhibited delayed rectifier potassium current, and chronically enhanced late sodium current. Dihydrotestosterone (30nM) reversed enzalutamide electrophysiological effects on induced pluripotent stem cells.

CONCLUSION

QT prolongation and TdP are a risk in men receiving enzalutamide and other ADTs.

CLINICAL TRIAL REGISTRATION

URL: https://www.clinicaltrials.gov. Unique identifier: NCT03193138.

P6590Androgenic effects on ventricular repolarization: a translational study from pharmacovigilance databases to iPSC-cardiomyocytes

Aim

Male hypogonadism, arising from various etiologies including androgen-deprivation therapies (ADT), has been reported as a risk-factor for acquired long-QT (aLQT) and Torsades de pointe (TdP). A full description of clinical features of aLQTS associated with ADT and of underlying mechanisms are lacking.

Method and results

We searched the WHO pharmacovigilance database for men (n=6,560,565) presenting with aLQT, TdP or sudden death (SD) associated with ADT. We identified 184 cases of aLQTS and/or TdP (11% fatal), and 99 with SD. Of the 10 ADT examined, 7 had a disproportional association (reporting-OR=1.4–4.7, p<0.05) with aLQT, TdP or SD. The minimum time to SD was 0.25 days. Enzalutamide (Enza, androgen antagonist) was associated with more deaths (17%, p<0.001) than other ADT used for prostate cancer (8.1%,Table). In cardiomyocytes derived from induced pluripotent stem cells (IPS-CMs) from men, we studied electrophysiological effects of enza and dihydrotestosterone (DHT). Acute and chronic enza (25μM) prolonged action potential durations (APD90-paced0.5Hz; 414±63 (control) vs. 951±67 (acute, p<0.01) and 1028±63msec (chronic, p<0.01), and generated early/delayed afterdepolarizations and/or triggered activity in drug treated cells (4/7 acute and 3/5 chronic). Enza acutely and chronically inhibited IKr, and chronically enhanced INa-L. DHT (30nM) reversed enza effects on IPS-CMs. In 7 men with aLQT and hypogonadism, ECGs showed low amplitude, bifid T-waves typical of IKr block which resolved with testosterone.

Table 1 ndeath/ntotal (%) aLQT TdP SD n/naLQTS±TdP±SD (%) with ADT considered suspect by reporter Leuprorelin 1,871/22,113 (8.5%) 33 16 18 28/55 (50.9%) Goserelin 471/5,821 (8.1%) 8 2 15 17/22 (77.3%) Triptorelin 52/1,517 (3.4%) 6 3 2 5/8 (62.5%) Degarelix 82/2,787 (2.9%) 7 4 3 10/11 (90.9%) Bicalutamide 724/10,144 (7.1%) 23 16 11 28/41 (68.3%) Flutamide 163/4075 (4%) 4 2 3 3/7 (42.9%) Enzalutamide 5,430/31,896 (17%) 19 4 13 30/32 (93.8%) Abiraterone 1,240/14,261 (8.7%) 19 7 10 29/31 (92.5%) Finasteride 1,062/33,877 (3.1%) 52 20 32 20/87 (23%) Dutasteride 248/15,177 (1.6%) 26 7 11 5/38 (13.2%) Total ADT* 10,540/127,385 (8.3%) 168 68 99 137/283 (48.4%) Number (n) of case reports in men in the WHO international pharmacovigilance database (VigiBase) by ADT through 08/09/2018. *Some patients were on combination ADT.

Enzalutamide electrophysiology IPS-CMs

Conclusion

ADT is a risk factor for aLQT and TdP. Androgens may be useful in TdP treatment of hypogonadic men.

Acknowledgement/Funding

INSERM

Androgenic Effects on Ventricular Repolarization: A Translational Study From the International Pharmacovigilance Database to iPSC-Cardiomyocytes

BACKGROUND

Male hypogonadism, arising from a range of etiologies including androgen-deprivation therapies (ADTs), has been reported as a risk factor for acquired long-QT syndrome (aLQTS) and torsades de pointes (TdP). A full description of the clinical features of aLQTS associated with ADT and of underlying mechanisms is lacking.

METHODS

We searched the international pharmacovigilance database VigiBase for men (n=6 560 565 individual case safety reports) presenting with aLQTS, TdP, or sudden death associated with ADT. In cardiomyocytes derived from induced pluripotent stem cells from men, we studied electrophysiological effects of ADT and dihydrotestosterone.

RESULTS

Among subjects receiving ADT in VigiBase, we identified 184 cases of aLQTS (n=168) and/or TdP (n=68; 11% fatal), and 99 with sudden death. Of the 10 ADT drugs examined, 7 had a disproportional association (reporting odds ratio=1.4-4.7; P<0.05) with aLQTS, TdP, or sudden death. The minimum and median times to sudden death were 0.25 and 92 days, respectively. The androgen receptor antagonist enzalutamide was associated with more deaths (5430/31 896 [17%]; P<0.0001) than other ADT used for prostate cancer (4208/52 089 [8.1%]). In induced pluripotent stem cells, acute and chronic enzalutamide (25 µM) significantly prolonged action potential durations (action potential duration at 90% when paced at 0.5 Hz; 429.7±27.1 (control) versus 982.4±33.2 (acute, P<0.001) and 1062.3±28.9 ms (chronic; P<0.001), and generated afterdepolarizations and/or triggered activity in drug-treated cells (11/20 acutely and 8/15 chronically). Enzalutamide acutely and chronically inhibited delayed rectifier potassium current, and chronically enhanced late sodium current. Dihydrotestosterone (30 nM) reversed enzalutamide electrophysiological effects on induced pluripotent stem cells.

CONCLUSIONS

QT prolongation and TdP are a risk in men receiving enzalutamide and other ADTs.

CLINICAL TRIAL REGISTRATION

URL: https://www.clinicaltrials.gov. Unique identifier: NCT03193138.

High risk of heart failure associated with desmoglein-2 mutations compared to plakophilin-2 mutations in arrhythmogenic right ventricular cardiomyopathy/dysplasia

BACKGROUND

Previous studies suggested that genetic status affects the clinical course of arrhythmogenic right ventricular cardiomyopathy/dysplasia (ARVC/D) patients. The aim of this study was to compare the outcome of desmoglein-2 (DSG2) mutation carriers to those who carry the plakophilin-2 (PKP2) mutation, the most common ARVC/D-associated gene.

METHODS AND RESULTS

Consecutive ARVC/D patients carrying a pathogenic mutation in PKP2 or DSG2 were selected from a national ARVC/D registry. The cumulative freedom from sustained ventricular arrhythmia and cardiac transplantation/death from heart failure (HF) during follow-up was assessed, compared between PKP2 and DSG2, and predictors for ventricular arrhythmia and HF events determined. Overall, 118 patients from 78 families were included: 27 (23%) carried a DSG2 mutation and 91 (77%) a PKP2 mutation. There were no significant differences between DSG2 and PKP2 mutation carriers concerning gender, proband status, age at diagnosis, T-wave inversion, or right ventricular dysfunction at baseline. DSG2 patients displayed more frequent epsilon wave (37% vs. 17%, P = 0.048) and left ventricular dysfunction at diagnosis (54% vs. 10%, P < 0.001). During a median follow-up of 5.6 years (2.5-16), DSG2 and PKP2 mutation carriers displayed a similar risk of sustained ventricular arrhythmia (log-rank P = 0.20), but DSG2 mutation carriers were at higher risk of transplantation/HF-related death (log-rank P < 0.001). The presence of a DSG2 mutation vs. PKP2 mutation was a predictor of transplantation/HF-related death in univariate Cox analysis (P = 0.0005).

CONCLUSIONS

In this multicentre cohort, DSG2 mutation carriers were found to be at high risk of end-stage HF compared to PKP2 mutation carriers, supporting careful haemodynamic monitoring of these patients. The benefit of early HF treatment needs to be assessed in DSG2 carriers.

Post-ablation prolongation of atrioventricular nodal refractory period is correlated with long-term success of cryoablation for atrioventricular nodal reentrant tachycardia in the case of the persistence of a residual jump

PURPOSE

A residual slow pathway after successful cryoablation for atrioventricular nodal reentrant tachycardia (AVNRT) is correlated with a higher recurrence rate. We described determinants of recurrence in subjects with a residual jump.

METHODS

We analyzed the data of subjects with acute successful slow pathway cryoablation for AVNRT using a 6-mm-tip cryocatheter. Success was defined as AVNRT non-inducibility. Patients with no baseline elicitable jump, no inducible AVNRT, and transient first atrioventricular (AV) block at the last site were excluded.

RESULTS

From 371 patients who underwent cryoablation from May 2002 to March 2011, 303 fulfilled the entry criteria (mean age, 41 ± 16; 222 women). Baseline AV nodal effective refractory period (ERP) was 272 ± 57 ms, postprocedural 331 ± 64 (P < 0.001), and the mean of the difference (Δ ERP) 60 ± 41. At the end of the procedure, 64 patients (21 %) had a residual jump, of whom 22 with a single echo. At 12 months follow-up, the actuarial recurrence-free rate was 70.3 % in patients with a residual jump and 86 % in those without (P = 0.01). In patients with a jump, only Δ AV nodal ERP was correlated with recurrence (37 ± 41 vs. 68 ± 47 ms; P < 0.04) while a single echo was not. The actuarial rate of recurrence was 60.8 % in patients with a Δ AV nodal ERP ≤ 30 ms and 18.8 % in those with a Δ AV nodal ERP >30 ms (P < 0.01).

CONCLUSIONS

Suppression of slow pathway conduction is the optimal endpoint for AVNRT cryoablation. A residual jump can be tolerated if AV nodal ERP postcryoablation is prolonged >30 ms.

[Survey into cardiac pacing in the Ile-de-France area for the year 2001: evaluation of indications]

A survey into the implantation of cardiac pacemakers during 2001 in the Ile-de-France area was carried out by the French National Insurance Medical Service in order to evaluate performance in all centres performing more than 10 primary implantations per year.

METHODS AND RESULTS

In 2001, 12 centres out of a total of 49 performed less than 50 primary implantations per year, representing 5% of the total regional activity, which was estimated to be 6414 procedures. The remaining 95% of procedures were spread evenly among 8 high-throughput centres (> 200 primary implantations per year) and 29 medium-throughput centres (50 to 200 primary implantations per year). Indications for pacing were analysed retrospectively by a team of regulatory doctors on a sample of 2176 patients with reference to the ACC/AHA/NASPE guidelines. After examination of the medical records, the indication was ranked as being class I, II or Ill (absence of indication). A valid indication was lacking in 8.2% of cases. Sinus node dysfunction represented 74.6% of the non-indications, and this classification had the predictive factors of asymptomatic dysfunction, and treatment with anti-arrhythmic or bradycardic medication. The proportion of class III interventions was significantly lower in the high-throughput centres (5.8 vs 9.9%, p < 0.05).

CONCLUSION

8.2% of primary pacing procedures were not indicated and resulted principally from asymptomatic sinus node dysfunction.