Michał Orczykowski

Ventricular fibrillation risk factors in over one thousand patients with accessory pathways

BACKGROUND Published data concerning risk factors of VF in WPW patients are inconsistent or contradictory. METHODS AND RESULTS We included 1007 patient (pts) (mean age 35 years; 45% female) with an accessory pathway (AP) referred for non pharmacological treatment. Group 1 consisted of 56 pts (42M, aged 34 ± 15 yrs) with an AP and documented VF and Group 2-951 pts (513M, aged 35 ± 15 yrs) with an AP and without VF. Univariate predictors of VF were: overt pre-excitation, male gender, multiple AP, large AP. Multivariate predictors were: overt pre-excitation, male gender and MAP. The mean shortest pre-excited RR interval during AF was significantly shorter in Group 1: 205 ± 27 vs. 243 ± 64, P=0.019. VF as an end point of the first arrhythmia episode (AVRT or AF) was observed in 20 pts (15M, 5F). Primary VF (no documented arrhythmia prior to aborted SCD) occurred in 16 pts (13M, 3F). The mean age of primary VF pts was significantly lower than of pts with history of AVRT or AVRT and/or AF (24.5 vs. 36.5 vs. 38 yrs., P<0.005 and P=0.002, respectively). Age at VF occurrence shows a bi-modal distribution with peak occurrences in the 2-nd/3-rd and 5-th decades. CONCLUSION In patients with an accessory pathway, overt pre-excitation, male gender and multiple AP constitute independent risk factors of VF episodes. Young patients in the 2-nd/3-rd and older patients in the 5-th decade might be at higher risk of VF occurrence.

Radiofrequency catheter ablation of accessory pathways in patients with Ebstein’s anomaly: At 8 years of follow-up

BACKGROUND Data regarding long-term follow-up of radiofrequency catheter ablation (RFCA) of accessory pathways (APs) in patients with Ebsteins anomaly (EA) are limited. The procedures are challenging due to multiple or wide APs. METHODS Analysis was performed on clinical and periprocedural data of patients with EA referred to the centre in order to perform catheter ablation of AP. The group consisted of 22 patients (female 40.9%, mean age 33.6 ± 19.1 years). The follow-up utilized electrocardiogram and Holter monitoring. RESULTS Twenty-two patients had 33 accessory pathways (8 patients had multiple APs, 11 patients broad AP). Twenty-nine different arrhythmias were ablated: 20 orthodromic atrioventricular reciprocating tachycardia (O-AVRT), 5 antidromic atrioventricular reciprocating tachycardia (A-AVRT), 3 slow/ fast atrioventricular nodal reentry tachycardia (s/f AVNRT) and 1 cavotricuspid-isthmus-dependent atrial flutter (CTI-AFL). In 3 (13.6%) patients multiple ablation targets for RFCA ablation were observed. The acute procedural success rate after the first RFCA performed was: 100% for AVNRT, 77.3% for APs and 50.0% for CTI-AFL ablation. Follow-up (mean 95.7 ± 49.8 months) was completed in 86.4% of patients. One patient had paroxysmal atrial fibrillation not targeted during ablation. One patient died due to heart failure 12 years after RFCA. Three patients who underwent RFCA of accessory pathways in the mid-1990s were lost in follow-up. CONCLUSIONS Radiofrequency ablation in patients with EA is challenging but safe and have a high short-term as well as long-term success rate.

Ablation of atrial tachyarrhythmias late after surgical correction of tetralogy of Fallot: long-term follow-up

BACKGROUND After the surgical correction of tetralogy of Fallot, surgical scars and natural obstacles form pathways capable of supporting an atrial tachyarrhythmia (AT). Radiofrequency (RF) ablation is effective, although the few studies published on this topic had relatively short follow-up periods. AIM The aims of the study were to evaluate the acute and long-term effects of RF ablation of AT and examine the charac-teristics of arrhythmia recurrence. METHODS Tetralogy of Fallot patients (n = 16, age 44.7 ± 10.7 years) referred for ablation of ATs, appearing 25.7 ± 9.6 years after repair, were studied. RESULTS Twenty-five ATs were ablated, including 16 cavo-tricuspid isthmus atrial flutters (CTI-AFLs) and nine intraatrial reentrant tachycardia (IART). In one patient with paroxysmal atrial fibrillation (PAF), pulmonary vein isolation was also performed. Ten patients had permanent, and six had paroxysmal arrhythmia prior to the first ablation. Four patients had PAF. Regardless of the type of first ablated arrhythmia, all 16 patients required CTI-AFL ablation. The effectiveness of the first RF ablation reached 88%. The acute efficacy of RF ablation was 100% for CTI-AFL and 78% for IART. Long-term follow-up was possible in 15 out of 16 patients (mean follow-up 68.8 ± 36.6 months). Four patients were free of sustained arrhythmia, nine (60%) had AF. After the last RF ablation, an episode suggestive of CTI-AFL/IART was documented only in one patient. CONCLUSIONS Ablation of CTI-AFL/IART in tetralogy of Fallot patients is safe and effective. AF was observed in most patients during the long-term follow-up. Regardless of the type of the first ablated arrhythmia, all patients required CTI-AFL ablation.

Safety of a simplified electrophysiological method of transseptal puncture. A single center’s experience

Introduction Transseptal puncture (TSP) is a part of many interventional cardiology procedures including left-sided arrhythmia catheter ablation, transvenous mitral commissurotomy, left atrial appendage occlusion and other catheter-based structural heart disease procedures [1]. Since 1959, when it was first performed [2], different techniques of TSP have been introduced. Guiding methods include fluoroscopy, pressure monitoring [3], intracardiac echocardiography (ICE) [4], transesophageal echocardiography (TEE) [3] and introduction of a pigtail catheter into the aortic root [5].

Risk factors of atrial fibrillation recurrence despite successful radiofrequency ablation of accessory pathway: At 11 years of follow-up

BACKGROUND Previous reports on patients with radiofrequency catheter ablation (RFCA) of accessory pathway (AP) and atrial fibrillation (AF) include only short follow-up periods. The aim of this study was to analyze predictors of recurrence of AF in patients after successful RFCA of APs over long term follow-up periods. METHODS Of the 1,007 patients who underwent non-pharmacological treatment of APs (between the years 1993-2008), data of 100 consecutive patients were retrospectively analyzed (75 men, mean age 43.6 ± 14.7), with the longest period of follow-up (mean 11.3 ± 3.5 years) after successful RFCA of AP. In Group 1, there were 72 patients (54 men, mean age 40.66 ± 13.85 years) without documented episodes of AF after RFCA of AP. Group 2 consisted of 28 patients (21 men, mean age 50.79 ± 14.49 years) with AF episodes despite successful elimination of AP. RESULTS In univariate analysis, patients from Group 1 were significantly younger at the time of abla-tion than patients from Group 2 (40.66 ± 13.85 vs. 50.79 ± 14.49 years; p = 0.002), had shorter his¬tory of AF episodes (4.11 ± 4.07 vs. 8.25 ± 7.50 years; p = 0.024) and had less frequently documented atrial tachycardia (AT) prior to ablation (3.39 vs. 20.00% years; p = 0.022). In multivariate analysis, the history of AF in years (p = 0.043), was an independent risk factor for AF recurrences. CONCLUSIONS Older patient age, longer history of AF and AT prior to RFCA of APs identified a sub-group of patients who required additional treatment. In the multivariate analysis, the history of AF in years (p = 0.043) was a risk factor for AF recurrence.

Characteristic features of patients with multiple accessory pathways

Abstract Objective Only limited clinical and electrophysiological data concerning patients (pts) with multiple accessory pathways (MAP) in comparison to large control groups are available. The aim of our study was to analyse these data from the largest cohort of patients with multiple accessory pathways and a large control group. Method and results We analysed data from pts with MAP (group 1) and pts with a single accessory pathway (AP) (group 2) referred for radiofrequency catheter ablation (RFCA) at our tertiary centre. Group 1 consisted of 124 pts (M 62.10%, mean age 33.00 ± 5.26) with MAP and RFCA. Group 2 consisted of 376 pts (M 51.20%, mean age 35.87 ± 16.15) with a single accessory pathway and RF ablation. Group 1 exhibited a higher incidence of overt APs (P < 0.0001), Ebstein anomaly (P = 0.001), ventricular fibrillation (P = 0.012), antidromic atrioventricular re-entrant tachycardia (A AVRT) (P = 0.025) and male gender (P = 0.038). The mean age at the first documented atrioventricular re-entrant tachycardia (AVRT) episode was lower in pts with MAP than in pts with single APs: 16.79 ± 13.41 vs 20.84 ± 14.29, respectively (P = 0.001). Concealed accessory pathways (P < 0.0001) occurred more frequently in the control group. Group 1 had more right-lateral (P = 0.0001), mid-septal (P = 0.0001), left-posterior (P = 0.01), left-anterior (P = 0.013) and left-lateral localizations of AP (P < 0.037). Conclusions The MAP group included statistically significantly more men, Ebstein anomaly and overt APs. The mean age of the first episode of atrioventricular re-entrant tachycardia was lower in pts with MAP. Certain distribution patterns are apparent for single and MAP. Pts with MAP are at higher risk of VF and antidromic atrioventricular re-entrant tachycardia.

Endocardial radiofrequency ablation for septal hypertrophy

Endocardial radiofrequency ablation of septal hypertrophy (ERASH) might be a potentially attractive treatment concept of symptomatic hypertrophic obstructive cardiomyopathy (HOCM). However, very few studies have been reported on such treatment. We present the immediate results and 2-year follow-up observation after ERASH. A 47-year-old male HOCM patient, after insertion of dual-chamber implantable cardioverter-defibrillator, with paroxysmal atrial fibrillation, in functional class New York Heart Association (NYHA) III despite optimal medical therapy, was referred for further treatment. Cardiac magnetic resonance revealed 31-mm-thick asymmetric hypertrophy of the basal septal segment (Fig. 1A, B), systolic anterior motion of the mitral valve leaflet with secondary mild mitral regurgitation, and extensive late gadolinium enhancement mostly in the hypertrophied segments. Maximal left ventricular outlet tract obstruction (LVOTO) gradient at rest was 47 mm Hg by continuous wave (CW) Doppler echocardiography and 60 mm Hg at rest in direct invasive measurement, and reached 160 mm Hg after premature ventricular contraction. Suboptimal septal branch anatomy excluded septal alcohol ablation (Fig. 1C, D). As the patient preferred a less invasive approach, ERASH was offered. After transseptal puncture, an ablation catheter was introduced into the left atrium and via mitral annulus into the left ventricle. CARTO-based three-dimensional electro-anatomical mapping of both ventricles was performed. A series of 11 radiofrequency pulses to the septal bulge was delivered from both the left and right ventricles. Direct postprocedural LVOTO gradient decreased to 15 mm Hg. Maximal troponin-I rise was 12 ng/mL (UNL < 0.03 ng/mL). On the seventh postprocedural day reduction of maximal LVOTO gradient to 27 mm Hg was noted by CW Doppler. N-terminal pro-B-type natriuretic peptide (NT-proBNP) decreased from 950 pg/mL to 590 pg/mL. Peak oxygen uptake was 19.7 mL/min/kg (50% of predicted normal value) by cardiopulmonary exercise testing (CPX). At 2-year follow-up the patient remained in functional class NYHA I/II. The maximal CW Doppler LVOTO gradient was 49 mm Hg and during Valsalva rose up to 68 mm Hg. Peak oxygen uptake was 21.4 mL/min/kg (55% of predicted normal value). NT-pro-BNP fluctuated from 1005 pg/mL to 490 pg/mL. However, at 3-year follow-up CW Doppler LVOTO gradient rose to 80 mm Hg at rest. Thus, surgical myectomy together with mitral valve replacement to artificial prosthesis was performed. We failed to show convincing LVOTO gradient reduction in our patient. Despite this, improvement of symptoms was observed and confirmed in objective tests (CPX). Some procedural details should be raised. First, the mean septal thickness in the study by Lawrenz et al. (J Am Coll Cardiol, 2011; 57: 572–576) was 22.5 mm, as opposite to 31 mm in our patient. A thicker septum may limit the ERASH effectiveness. Secondly, the ablation site in that study was either left or right ventricle, and nobody received both ventricle-sided ablation. No differences on LVOTO reduction between left-sided and right-sided ablation were observed and one-side ventricle septum ablation versus both-sides septum ablation was not tested. One may hypothesize that deeper the ablation, higher the risk of conduction system damage. Thus, the aim of our treatment strategy to perform ablation on both ventricle sites was to increase the ablated thickness without deep ablation penetration. ERASH seems to be an attractive catheter-based treatment concept for HOCM patients irrespective of septal vasculature. Although we observed clinical improvement, lack of convincing, long-term LVOTO reduction does not allow us to recommend this treatment approach and warrants further development of dedicated ERASH catheters. Figure 1. A, B. Cardiac magnetic resonance showing excessive hypertrophy of the basal septum in long-axis projection and short-axis view, respectively; C, D. Angiography of the left coronary artery and the left anterior descending coronary artery, respectively D C A

Early stage of left atrium remodelling predicts better outcome in long-term follow-up of atrial fibrillation ablation.

BACKGROUND Radiofrequency catheter ablation (RFCA) has been increasingly used for the treatment of patients with symptomatic atrial fibrillation (AF). AIM To identify simple pre-procedural success predictors of RFCA in patients with AF. METHODS AND RESULTS It comprised 294 consecutive patients (mean age 54 ± 11 years, 71% male) with symptomatic AF (28% - paroxysmal with short episodes (< 12 h); 50% - paroxysmal with episodes ≥ 12 h and < 7 days; 11.5% - persistent; 10.5% - long standing persistent), having undergone the first RFCA. Before RFCA, all patients underwent pulmonary vein (PV) anatomy imaging and echocardiographic left atrium diameter (LAD) evaluation. PV periostial or antral isolation guided by electroanatomical mapping was performed with additional lines or complex fractionated electrograms ablation (if required). Outcomes were defined as clinical success (complete or improvement) or failure. After a mean follow-up of 36.9 ± 13 months, clinical success was observed in 90.5% of patients, made up of 47.3% complete success, and 43.2% improvement. Patients with short AF episodes underwent fewer procedures (1.6 vs. 2, p = 0.026) and had the highest clinical (97.6%) and complete (63.9%) success rates. AF episodes < 12 h (p < 0.001), LAD < 4 cm (p = 0.01) and male gender (p = 0.002) independently predicted RFCA long-term clinical success. PV anatomy did not correlate with RFCA outcome. A trend was observed towards a larger number of procedures in patients with atypical PV anatomy (p = 0.059). CONCLUSIONS AF ablation should be performed in the early stage of AF, before structural remodelling development.

P1-63 FIRST EPISODE OF ATRIAL FIBRILLATION IN OVERT AND CONCEALED WOLF-PARKINSON-WHITE SYNDROME

Background: Long refractory period of the A-V node is a natural barrier, which protects the ventricles from too fast heart rhythm. In WPW syndrome, AF is particularly dangerous when accessory pathway (AP) has short refractory period. The aim of our study was to analyze the occurrence of AF in dependence on sex, age, property of AP and other factors (CHD, HT) Methods: 747 pts, mean age 35.5, underwent non-pharmacological treatment of WPW (years 1988-2005). 221 (39.5%) of them (68 F, 153 M) had documented atrial fibrillation. The results of 12 lead ECG Holter, ECG monitoring, and an echocardiography study were analyzed. Results: 140 pts (63.3%) have had episode of AF and AVRT, 79 (25,5%) only AF. 20 pts (9%) have documented VF. 18% had HT, 7,3% CHD, 13,7% changes in coronary arteries, 8,7% valvular heart disease. 20% underwent cardioversion. Women had the first episode of AF most frequently at 4 decade (25.5%), men at 3rd (27.6%). The mean age of the first AF episode in men was significantly lower than women (32.4 vs 39.6). More frequently AF occured in pts with left sided AP (61%) than right-sided (30%). Midseptal occurs seldom (9%). AF occurred most frequently in overt APs – 81.3% (intermittent – 11%, and concealed – 7.7%). Conclusions: Men have had AF episodes 2,2 times more often than woman. Pts with avrt have had AF earlier than pts without avrt (36 vs 46). Men have had first episode of AF earlier than women (32.4 vs 39.6).