Swiss National Registry on Catheter Ablation Procedures: Changing Trends over the Last 20 Years.

The Swiss Ablation Registry provides a national database for electrophysiologic studies and catheter ablations. We analyzed the database to provide an in-depth look at changing trends over the last 20 years. During the study period a total of 78622 catheter ablations (age 61.0 ± 1.2 years; 63.7% male) were performed in 29 centers. The number of ablations increased by approximately ten-fold in 20 years. Ablation for atrial fibrillation (AF) was the main driver behind this increase, with more than hundred-fold (39.7% of all ablations in 2019). Atrioventricular-nodal-reentrant-tachycardia (AVNRT) and accessory pathways, being the main indications for ablation in 2000 (44.1%/25.1%, respectively), made up of only a small proportion (15.2%/3.5%,) respectively in 2019. Fluoroscopy, ablation, and procedure durations were reduced for all ablations over time. The highest repeat ablations were performed for ventricular tachycardia and AF (24.4%/24.3%). The majority of ablations (63.0%) are currently performed in private hospitals and non-university public hospitals whereas university hospitals had dominated (82.4%) at the turn of the century. A pronounced increase in the number of catheter ablations in Switzerland was accompanied by a marked decrease in fluoroscopy, ablation, and procedure durations. We observed a shift toward more complex procedures in older patients with comorbidities.

Prognostic significance of a low T/R ratio in Brugada syndrome.

OBJECTIVES: To determine the prognostic value of a low T/R ratio, defined as the amplitude ratio between the T waves and the R waves, in patients (pts) with a spontaneous type-1 Brugada pattern (SBT1). BACKGROUND: Abnormalities of myocardial repolarization may play a key role in the initiation of ventricular fibrillation (VF) in Brugada syndrome (BrS). Recent studies have shown that the height of the T waves and the T/R ratio are inversely proportional to sudden cardiac arrest (SCA) risk in early repolarization syndrome and hypertrophic cardiomyopathy. METHODS: In an international retrospective study, we reviewed 115 pts. (105 males, 91.3%). 45 had VF and/or SCA (38.7 ±â€¯11.5 years old, all males), while 70 (49.3 ±â€¯12.0 years, 10 women) remained free of ventricular arrhythmia. 6 ECG markers plus the T/R ratio in leads V5 & II were studied. RESULTS: The T/R ratio among leads II & V5 was significantly lower in the VF/SCA group (0.24 [0.14; 0.38]vs. 0.34 [0.24; 0.45]; p = 0.006). 44.4% of pts. in the VF/SCA group had a lowest T/R ratio among leads II & V5 ≤ 0.17 compared to 11.4% in the non-VF/SCA group (p < 0.001). In multivariate analysis, a lowest T/R ratio among leads II & V5 ≤ 0.17 was independently associated with VF/SCA (OR 6.10, 95% CI 1.92-19.40; p = 0.002). Type 1 Brugada pattern in the peripheral leads (OR 10.78) and early repolarization (OR 3.60) were other independent markers of VF/SCA. CONCLUSION: A low T/R ratio among leads II & V5 is an independent marker for VF/SCA risk in patients with type-1 Brugada pattern.

Prediction of ventricular arrhythmias in patients with a spontaneous Brugada type 1 pattern: the key is in the electrocardiogram.

AIMS: There is currently no reliable tool to quantify the risks of ventricular fibrillation or sudden cardiac arrest (VF/SCA) in patients with spontaneous Brugada type 1 pattern (BrT1). Previous studies showed that electrocardiographic (ECG) markers of depolarization or repolarization disorders might indicate elevated risk. We aimed to design a VF/SCA risk prediction model based on ECG analyses for adult patients with spontaneous BrT1. METHODS AND RESULTS: This retrospective multicentre international study analysed ECG data from 115 patients (mean age 45.1 ± 12.8 years, 105 males) with spontaneous BrT1. Of these, 45 patients had experienced VF/SCA and 70 patients did not experience VF/SCA. Among 10 ECG markers, a univariate analysis showed significant associations between VF/SCA and maximum corrected Tpeak-Tend intervals ≥100 ms in precordial leads (LMaxTpec) (P < 0.001), BrT1 in a peripheral lead (pT1) (P = 0.004), early repolarization in inferolateral leads (ER) (P < 0.001), and QRS duration ≥120 ms in lead V2 (P = 0.002). The Cox multivariate analysis revealed four predictors of VF/SCA: the LMaxTpec [hazard ratio (HR) 8.3, 95% confidence interval (CI) 2.4-28.5; P < 0.001], LMaxTpec + ER (HR 14.9, 95% CI 4.2-53.1; P < 0.001), LMaxTpec + pT1 (HR 17.2, 95% CI 4.1-72; P < 0.001), and LMaxTpec + pT1 + ER (HR 23.5, 95% CI 6-93; P < 0.001). Our multidimensional penalized spline model predicted the 1-year risk of VF/SCA, based on age and these markers. CONCLUSION: LMaxTpec and its association with pT1 and/or ER indicated elevated VF/SCA risk in adult patients with spontaneous BrT1. We successfully developed a simple risk prediction model based on age and these ECG markers.

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.

Cardiac Resynchronisation Therapy (CRT) Survey II: CRT implantation in Europe and in Switzerland.

AIM: Between October 2015 and December 2016, 11,088 patients from 42 countries having cardiac resynchronisation therapy (CRT) devices implanted were included in the CRT II Survey. We compared the characteristics of Swiss CRT recipients with the overall European population. METHODS: Demographic and procedural data from seven Swiss centres recruiting all consecutive patients undergoing either de-novo CRT implantation or an upgrade to a CRT system were collected and compared with the European population. RESULTS: A total of 320 Swiss patients (24.4% female, mean age 71.0 ± 10.2 years, 47% ischaemic cardiomyopathy) were enrolled, which amounts to 38% of all CRT implantations in Switzerland during this period. Of the patients enrolled, 38% had atrial fibrillation, 27% second- or third-degree atrioventricular block, and 68% complete left bundle-branch block. Swiss patients had significantly less often the classical indication of heart failure with a wide QRS complex (40 vs 61%; odds ratio [OR] 0.44, 95% confidence interval [CI] 0.35-0.55; p <0.001). Compared with the European population, Swiss patients were significantly older (71 vs 68.5 years, p <0.001), less symptomatic from heart failure and had more chronic kidney disease. Swiss patients significantly more often received a CRT-pacemaker (37 vs 30%; OR 1.37; 95% CI 1.09-1.73; p = 0.007) and quadripolar left ventricular leads (69 vs 57%; OR 1.67, 95% CI 1.32-2.13; p <0.001). CONCLUSION: Compared with European CRT recipients, Swiss CRT patients are older, less symptomatic and suffer more often from comorbidities. Although two thirds of the implantations were CRT-defibrillator systems, Swiss patients more often received CRT-pacemaker systems than their European counterparts.

Non-sustained ventricular tachycardia in patients with congenital heart disease: An important sign?

BACKGROUND: Sustained ventricular tachycardia (susVT) and ventricular fibrillation (VF) are observed in adult patients with congenital heart disease (CHD). These dysrhythmias may be preceded by non-sustained ventricular tachycardia (NSVT). The aims of this study are to examine the 1] time course of ventricular tachyarrhythmia (VTA) in a large cohort of patients with various CHDs and 2] the development of susVT/VF after NSVT. METHODS: In this retrospective study, patients with VTA on ECG, 24-hour Holter or ICD-printout or an out-of-hospital-cardiac arrest due to VF were included. In patients with an ICD, the number of shocks was studied. RESULTS: Patients (N=145 patients, 59% male) initially presented with NSVT (N=103), susVT (N=25) or VF (N=17) at a mean age of 40 ± 14 years. Prior to VTA, 58 patients had intraventricular conduction delay, 14 an impaired ventricular dysfunction and 3 had coronary artery disease. susVT/VF rarely occurred in patients with NSVT (N=5). Fifty-two (36%) patients received an ICD; appropriate and inappropriate shocks, mainly due to supraventricular tachycardia (SVT), occurred in respectively 15 (29%) (NSVT: N=1, susVT: N=9, VF: N=5) and 12 (23%) (NSVT: N=4, susVT: N=5, VF: N=3) patients. CONCLUSIONS: VTA in patients with CHD appear on average at the age of 40 years. susVT/VF rarely developed in patients with only NSVT, whereas recurrent episodes of susVT/VF frequently developed in patients initially presenting with susVT/VF. Hence, a wait-and-see treatment strategy in patients with NSVT and aggressive therapy of both episodes of VTA and SVT in patients with susVT/VF seems justified.

Electrocardiographic characteristics of patients with funnel chest before and after surgical correction using pectus bar: A new association with precordial J wave pattern.

OBJECTIVE: Abnormal ECG findings suggestive of cardiac disease are frequent in patients with funnel chest, although structural heart disease is rare. Electrocardiographic characteristics and changes following new surgical treatments in young adults are not described so far. The aim of the study was to analyze electrocardiographic characteristics of patients with funnel chest before and after minimally invasive funnel chest correction by the Nuss procedure. METHODS: Twenty-six patients with surgical correction of funnel chest using pectus bar were included. Twelve-lead ECGs before and later than one year after surgery were analyzed. RESULTS: In postoperative ECGs, amplitude of P wave in lead II and negative terminal amplitude of P wave in lead V1 decreased from 0.13 to 0.10mV (p=0.03), and from 0.10 to 0.04mV (p<0.001), respectively. Mean QRS duration decreased from 108ms to 98ms (p=0.003) after correction. A pathological left and right Sokolow-Lyon index was observed in 35% and 23% of patients before, versus 8% (p=0.04) and 0% (p=0.01) after correction, respectively. In contrast, the rate of patients with J wave pattern in precordial leads V4-V6 increased from 8% before to 42% after surgery (p=0.004). CONCLUSIONS: ECG abnormalities in patients with funnel chest are frequent, and can normalize after surgical correction by the Nuss procedure. De novo J wave pattern in precordial leads V4-V6 is a frequent finding after surgical funnel chest correction using pectus bar.

Time Course of Atrial Fibrillation in Patients With Congenital Heart Defects.

BACKGROUND: The incidence of atrial fibrillation (AF) is rising in the aging patients with congenital heart defects (CHD). However, studies reporting on AF in patients with CHD are scarce. The aim of this multicenter study was to examine in a large cohort of patients with a variety of CHD: (1) the age of onset and initial treatment of AF, coexistence of atrial tachyarrhythmia and (2) progression of paroxysmal to (long-standing) persistent/permanent AF during long-term follow-up. METHODS AND RESULTS: Patients (n=199) with 15 different CHD and documented AF episodes were studied. AF developed at 49±17 years. Regular atrial tachycardia (AT) coexisting with AF occurred in 65 (33%) patients; 65% initially presented with regular AT. At the end of a follow-up period of 5 (0-24) years, the ECG showed AF in 81 patients (41%). In a subgroup of 114 patients, deterioration from paroxysm of AF to (long-standing) persistent/permanent AF was observed in 29 patients (26%) after only 3 (0-18) years of the first AF episode. Cerebrovascular accidents/transient ischemic attacks occurred in 26 patients (13%), although a substantial number (n=16) occurred before the first documented AF episode. CONCLUSIONS: Age at development of AF in patients with CHD is relatively young compared with the patients without CHD. Coexistence of episodes of AF and regular AT occurred in a considerable number of patients; most of them initially presented with regular AT. The fast and frequent progression from paroxysmal to (long-standing) persistent or permanent AF episodes justifies close follow-up and early, aggressive therapy of both AT and AF.

Prevalence and significance of rare RYR2 variants in arrhythmogenic right ventricular cardiomyopathy/dysplasia: results of a systematic screening.

BACKGROUND: Arrhythmogenic right ventricular cardiomyopathy/dysplasia (ARVC/D) is a genetic disease predominantly caused by desmosomal gene mutations that account for only ~50% of cases. Ryanodine receptor 2 (RYR2) gene mutations usually cause catecholaminergic polymorphic ventricular tachycardia but have been associated with a peculiar phenotype named ARVC2. OBJECTIVE: We aimed to determine the prevalence and phenotype associated with RYR2 mutations in a large ARVC/D population. METHODS: We analyzed the whole RYR2 coding sequence by Sanger sequencing in 64 ARVC/D probands without desmosomal gene mutations. RESULTS: We have identified 6 rare missense variants: p.P1583S, p.A2213S, p.G2367R, p.Y2932H, p.V3219M, and p.L4670V. It corresponds to a 9% prevalence of rare RYR2 variants in the ARVC/D population (6 of 64 probands), which is significantly higher than the estimated frequency of rare RYR2 variants in controls (Fisher exact test, P = .03). Phenotypes associated with RYR2 variants were similar to desmosome-related ARVC/D, associating typical electrocardiographic abnormalities at rest, frequent monomorphic ventricular tachycardia, right ventricular dilatation, wall motion abnormalities, and fibrofatty replacement when histopathological examination was available. CONCLUSION: In this first systematic screening of the whole coding region of the RYR2 gene in a large ARVC/D cohort without mutation in desmosomal genes, we show that putative RYR2 mutations are frequent (9% of ARVC/D probands) and are associated with a conventional phenotype of ARVC/D, which is in contrast with previous findings. The results support the role of the RYR2 gene in conventional ARVC/D.

Usefulness of electrocardiographic parameters for risk prediction in arrhythmogenic right ventricular dysplasia.

The value of electrocardiographic findings predicting adverse outcome in patients with arrhythmogenic right ventricular dysplasia (ARVD) is not well known. We hypothesized that ventricular depolarization and repolarization abnormalities on the 12-lead surface electrocardiogram (ECG) predict adverse outcome in patients with ARVD. ECGs of 111 patients screened for the 2010 ARVD Task Force Criteria from 3 Swiss tertiary care centers were digitized and analyzed with a digital caliper by 2 independent observers blinded to the outcome. ECGs were compared in 2 patient groups: (1) patients with major adverse cardiovascular events (MACE: a composite of cardiac death, heart transplantation, survived sudden cardiac death, ventricular fibrillation, sustained ventricular tachycardia, or arrhythmic syncope) and (2) all remaining patients. A total of 51 patients (46%) experienced MACE during a follow-up period with median of 4.6 years (interquartile range 1.8 to 10.0). Kaplan-Meier analysis revealed reduced times to MACE for patients with repolarization abnormalities according to Task Force Criteria (p = 0.009), a precordial QRS amplitude ratio (∑QRS mV V1 to V3/∑QRS mV V1 to V6) of ≤ 0.48 (p = 0.019), and QRS fragmentation (p = 0.045). In multivariable Cox regression, a precordial QRS amplitude ratio of ≤ 0.48 (hazard ratio [HR] 2.92, 95% confidence interval [CI] 1.39 to 6.15, p = 0.005), inferior leads T-wave inversions (HR 2.44, 95% CI 1.15 to 5.18, p = 0.020), and QRS fragmentation (HR 2.65, 95% CI 1.1 to 6.34, p = 0.029) remained as independent predictors of MACE. In conclusion, in this multicenter, observational, long-term study, electrocardiographic findings were useful for risk stratification in patients with ARVD, with repolarization criteria, inferior leads TWI, a precordial QRS amplitude ratio of ≤ 0.48, and QRS fragmentation constituting valuable variables to predict adverse outcome.

Different prognostic value of functional right ventricular parameters in arrhythmogenic right ventricular cardiomyopathy/dysplasia.

BACKGROUND: The value of standard 2-dimensional transthoracic echocardiographic parameters for risk stratification in patients with arrhythmogenic right ventricular cardiomyopathy/dysplasia (ARVC/D) is controversial. METHODS AND RESULTS: We investigated the impact of RV fractional area change (FAC) and tricuspid annulus plane systolic excursion (TAPSE) for the prediction of major adverse cardiovascular events (MACE) defined as the occurrence of cardiac death, heart transplantation, survived sudden cardiac death, ventricular fibrillation, sustained ventricular tachycardia, or arrhythmogenic syncope. Among 70 patients who fulfilled the 2010 ARVC/D Revised Task Force Criteria and underwent baseline transthoracic echocardiography, 37 (53%) patients experienced MACE during a median follow-up period of 5.3 (interquartile range, 1.8-9.8) years. Average values for FAC, TAPSE, and TAPSE indexed to body surface area (BSA) decreased over time (P=0.03 for FAC, P=0.03 for TAPSE, and P=0.01 for TAPSE/BSA, each versus baseline). In contrast, median RV end-diastolic area increased (P=0.001 versus baseline). Based on the results of Kaplan-Meier estimates, the time between baseline transthoracic echocardiography and experiencing MACE was significantly shorter for patients with FAC <23% (P<0.001), TAPSE <17 mm (P=0.02), or right atrial short axis/BSA ≥25 mm/m(2) (P=0.04) at baseline. A reduced FAC constituted the strongest predictor of MACE (hazard ratio, 1.08 per 1% decrease; 95% confidence interval, 1.04-1.12; P<0.001) on bivariable analysis. CONCLUSIONS: This long-term observational study indicates that TAPSE and dilation of right-sided cardiac chambers are associated with an increased risk for MACE in patients with ARVC/D with advanced disease and a high risk for adverse events. However, FAC is the strongest echocardiographic predictor of adverse outcome in these patients. Our data advocate a role for transthoracic echocardiography in risk stratification in patients with ARVC/D, although our results may not be generalizable to lower-risk ARVC/D cohorts.

Radio-frequency ablation as primary management of well-tolerated sustained monomorphic ventricular tachycardia in patients with structural heart disease and left ventricular ejection fraction over 30%.

AIMS: Patients with well-tolerated sustained monomorphic ventricular tachycardia (SMVT) and left ventricular ejection fraction (LVEF) over 30% may benefit from a primary strategy of VT ablation without immediate need for a 'back-up' implantable cardioverter-defibrillator (ICD). METHODS AND RESULTS: One hundred and sixty-six patients with structural heart disease (SHD), LVEF over 30%, and well-tolerated SMVT (no syncope) underwent primary radiofrequency ablation without ICD implantation at eight European centres. There were 139 men (84%) with mean age 62 ± 15 years and mean LVEF of 50 ± 10%. Fifty-five percent had ischaemic heart disease, 19% non-ischaemic cardiomyopathy, and 12% arrhythmogenic right ventricular cardiomyopathy. Three hundred seventy-eight similar patients were implanted with an ICD during the same period and serve as a control group. All-cause mortality was 12% (20 patients) over a mean follow-up of 32 ± 27 months. Eight patients (40%) died from non-cardiovascular causes, 8 (40%) died from non-arrhythmic cardiovascular causes, and 4 (20%) died suddenly (SD) (2.4% of the population). All-cause mortality in the control group was 12%. Twenty-seven patients (16%) had a non-fatal recurrence at a median time of 5 months, while 20 patients (12%) required an ICD, of whom 4 died (20%). CONCLUSION: Patients with well-tolerated SMVT, SHD, and LVEF > 30% undergoing primary VT ablation without a back-up ICD had a very low rate of arrhythmic death and recurrences were generally non-fatal. These data would support a randomized clinical trial comparing this approach with others incorporating implantation of an ICD as a primary strategy.

Catheter ablation of stable ventricular tachycardia before defibrillator implantation in patients with coronary heart disease (VTACH): an on-treatment analysis.

BACKGROUND: In the Ventricular Tachycardia Ablation in Coronary Heart Disease (VTACH) study, an intention-to-treat approach was used and may have diminished the observed degree of treatment effect. We present a subanalysis of the VTACH study by treatment actually received. METHODS AND RESULTS: The VTACH study was a prospective, open, randomized controlled trial, undertaken in 16 European centers, comparing defibrillator implantation with and without ventricular tachycardia (VT) ablation in patients with stable VT, previous myocardial infarction, and reduced left-ventricular ejection fraction. Of the 52 patients in the ablation group, 7 (13%) did not receive VT ablation and 19% of patients assigned to implantable cardioverter defibrillator (ICD) only treatment group crossed over and had an ablation. The primary endpoint (first recurrence of any documented VT or ventricular fibrillation [VF]) was reached after a median of 19.5 months in the ablation group and 5.9 months in the ICD only group (P = 0.01). Overall, 685 VT/VF events occurred per year of follow-up in 22 patients of the ablation group and 4,986 events in 43 patients of the control group (P = 0.024). In the ICD only group, median numbers of VT/VF episodes were 25 (IQR 5.8-45.3) and 1.5 (IQR 0-24.8) per patient and year before and after crossover (n = 12), respectively. CONCLUSION: On-treatment analysis of the VTACH study emphasizes the effectiveness of VT ablation in patients receiving ICD treatment because of monomorphic VT post myocardial infarction. VT ablation clearly prolonged time to recurrence of VT/VF episodes and markedly decreased VT/VF burden.

Prevalence of asymptomatic and electrically undetectable intracardiac inside-out abrasion in silicon-coated Riata® and Riata® ST implantable cardioverter-defibrillator leads.

BACKGROUND: Recently, several cases of symptomatic and/or electrically detectable intracardiac inside-out abrasions in silicon-coated Riata® and Riata® ST leads have been described. However, the prevalence in asymptomatic patients with unremarkable implantable cardioverter defibrillator (ICD) interrogation is unknown. The aim of this study was to determine the prevalence of asymptomatic and electrically undetectable intracardiac inside-out abrasion in silicon-coated Riata® and Riata® ST leads. METHODS: All 52 patients with an active silicone-coated Riata® and Riata® ST lead followed up in our outpatient clinic were scheduled for a premature ICD interrogation and a biplane chest radiograph. When an intracardiac inside-out abrasion was suspected, this finding was confirmed by fluoroscopy. RESULTS: Mean time since implantation was 71 ± 18 months. An intracardiac inside-out abrasion was confirmed by fluoroscopy in 6 patients (11.5%). Mean time from lead implantation to detection of intracardiac inside-out abrasion was 79 ± 14 months. In all patients with an intracardiac inside-out abrasion, ICD interrogation showed normal and stable electrical parameters. Retrospectively, in 4 of these 6 patients, a coronary angiography performed 25 ± 18 months before diagnosis of intracardiac inside-out abrasion already showed the defect. Despite undetected intracardiac inside-out abrasion, 2 of these 4 patients experienced adequate antitachycardia pacing and ICD-shocks. ICD leads were replaced in all 6 patients. CONCLUSIONS: The prevalence of asymptomatic intracardiac inside-out abrasion in silicon-coated Riata® and Riata® ST leads is higher than 10% when assessed by fluoroscopy, and most intracardiac inside-out abrasions are not detectable by ICD interrogation.

Atrioventricular conduction after transcatheter aortic valve implantation and surgical aortic valve replacement.

INTRODUCTION: Atrioventricular conduction abnormalities (AVCA) may complicate transcatheter aortic valve implantation (TAVI) and surgical aortic valve replacement (SAVR). The aim of this study was to prospectively evaluate AVCA after TAVI and SAVR. METHODS AND RESULTS: Among 50 patients undergoing TAVI and 25 patients undergoing SAVR a continuous 7-day Holter electrocardiogram (ECG) was recorded after the procedure. ECGs during TAVI and 12-lead ECGs before and 1 and 7 days after TAVI and SAVR were analyzed. At baseline, TAVI patients were older (mean 82.1 vs 75.4, P < 0.001), had a longer PR interval (median 200 milliseconds vs 175 milliseconds, P = 0.004) and broader QRS width (median 100 milliseconds vs 80 milliseconds, P = 0.007) than SAVR patients. New AVCA were observed among 29 TAVI patients (58%), mostly new left bundle branch block (76%). Predilatation induced new AVCA in 14 TAVI patients (28%). New AVCA resolved within 24 hours in 15 TAVI patients (30%), and persisted in 14 TAVI (28%) and 3 SAVR patients (12%, P = 0.12). Among patients with persistent QRS width <120 milliseconds during the first 24 hours after TAVI, QRS width remained stable during the remainder of the observation period. During Holter monitoring complete AV block was observed in 4 TAVI patients (8%) and 3 SAVR patients (12%; P = 0.68). CONCLUSIONS: Almost half of AVCA during TAVI are induced by predilatation, but half of them resolve within 24 hours. Persistent AVCA are more frequently observed after TAVI than SAVR. If QRS width is below 120 milliseconds the first day after TAVI, the risk of late AVCA seems low.

Is 7-day event triggered ECG recording equivalent to 7-day Holter ECG recording for atrial fibrillation screening?

OBJECTIVE: Prolonged ECG monitoring is standard for atrial fibrillation (AF) screening. This study investigated whether 7-day event triggered (tECG) ECG recording is equivalent to 7-day continuous Holter (cECG) ECG recording for AF screening. DESIGN: Both a cECG (Lifecard CF) and a tECG (R.Test Evolution 3) were simultaneously worn for 7 days by patients with known or suspected paroxysmal AF. RESULTS: In 100 corresponding recordings, median effective duration of monitoring was 165 h (range 10-170 h) for cECG and 137 h (0-169 h) for tECG (p<0.001). Median number and total duration of arrhythmias (AF, atrial flutter or atrial tachycardia) of ≥30 s duration recorded by cECG were 10 (1-428) and 1030 min (≤1-10,020), respectively. An arrhythmia was recorded in 42 cECGs (42%) versus 37 tECGs (37%, p=0.56). Triggered ECG failed to record an arrhythmia in cECG positive cases because of interrupted monitoring in four cases and because of recording failure in one case. Sensitivity, specificity, and positive and negative predictive values of tECG therefore were 88%, 100%, 100%, and 92%, respectively. Quantitative cECG analysis required a median of 20 min (3-205 min) and qualitative tECG analysis 4 min (1-20 min; p<0.001). Skin irritation was a frequent side effect (42%) resulting in premature removal of devices in 16% of patients. CONCLUSION: Sensitivity of tECG for AF screening as compared to cECG is lower, mainly because of shorter effective monitoring duration. Qualitative tECG analysis is less time consuming than quantitative cECG analysis. Skin irritation is a frequent side effect and reason for premature device removal.

Long-term outcome of ablative therapy of post-operative atrial tachyarrhythmias in patients with tetralogy of Fallot: a European multi-centre study.

AIM: Post-operative atrial tachyarrhythmias (AT) in patients with tetralogy of Fallot (ToF) are associated with congestive heart failure, stroke, and cardiac death. Effective treatment is therefore essential. The aim of the study is to evaluate long-term outcome of ablative therapy of AT in ToF patients and to study characteristics of AT recurrences. METHODS AND RESULTS: Tetralogy of Fallot patients (N = 38, age 43 ± 12 years) referred for ablation of post-operative AT, appearing 26 ± 10 years after complete repair, were studied. Electro-anatomical/entrainment mapping was performed prior to ablation. Successful ablation was defined as (i) achievement of bi-directional conduction block for isthmus-dependent atrial flutter (IDAF), (ii) termination during ablation for intra-atrial reentrant tachycardia (IART) and focal atrial tachycardia (FAT). Fifty-two AT were ablated, including 37 IDAF [cycle length (CL) 294 ± 70 ms], 11 IART (CL 295 ± 46 ms), and 4 FAT (CL 371 ± 93 ms). Ablation was successful in 98%. Fifty-one of 52 AT involved the cavo-tricuspid isthmus and/or the area between scar tissue related to prior atriotomy incisions and the inferior caval vein. Multiple AT developed in 11 patients, with different mechanisms in 9. After 45 ± 24 months, 32 patients were in sinus rhythm; 5 used anti-arrhythmic drugs. CONCLUSION: Ablative therapy of AT in ToF patients is an effective curative treatment modality with a high procedural success rate. Sinus rhythm during long-term follow-up was obtained in the majority of patients. Fifty-one of 52 AT originated from sites related to surgical incisions created at complete repair, suggesting that extending the atriotomy incision towards the inferior caval vein during cardiac surgery combined with surgical ablation of the cavo-tricuspid isthmus will be effective in preventing development of AT.