Early markers of atrial fibrillation recurrence after pulmonary vein isolation

Background: Postprocedural atrial extrasystole (AES) frequency predicts atrial fibrillation (AF) recurrence after pulmonary vein isolation (PVI) in patients with paroxysmal AF. However, the predictive value of preprocedural AES frequency is unknown. We investigate whether preprocedural AES frequency is a feasible marker to predict (timing of) AF recurrence after PVI. Methods: Patients (N = 684) with paroxysmal or persistent AF undergoing first-time PVI were evaluated for (a) the frequency of AES/day on Holter recordings without AF prior to PVI, (b) AF episodes during the 90 days blanking period, and (c) AF recurrences afterward. The correlation between AES/day and both development and timing of AF recurrences was tested. Results: Preprocedural AES/day was similar in patients with paroxysmal (66 [20-295] AES/day) and persistent AF (115 [12-248] AES/day, P =.915). During the blanking period, 302 (44.2%) patients showed AF episodes. AF recurred in 379 (55.4%) patients at 203 (105-400) days after PVI. AF recurred more frequently in patients with persistent (N = 104 [69.3%]) than in patients with paroxysmal AF (N = 275 [51.5%], P <.001). Frequency of AES prior to PVI was not correlated with development (P =.203) or timing (P =.478) of AF recurrences. AF recurrences occurred both more frequently (P <.001) and earlier (P <.000) in patients with AF during the blanking period. Conclusion: AES/day prior to PVI is not correlated with (timing of) AF during the blanking period or AF recurrences, and is therefore not a feasible marker for AF recurrences in patients with PAF. AF during the blanking period is correlated with AF recurrence

Impact of ischemic and valvular heart disease on atrial excitation

Background--The influence of underlying heart disease or presence of atrial fibrillation (AF) on atrial excitation during sinus rhythm (SR) is unknown. We investigated atrial activation patterns and total activation times of the entire atrial epicardial surface during SR in patients with ischemic and/or valvular heart disease with or without AF. Methods and Results--Intraoperative epicardial mapping (N=128/192 electrodes, interelectrode distances: 2 mm) of the right atrium, Bachmann's bundle (BB), left atrioventricular groove, and pulmonary vein area was performed during SR in 253 patients (186 male [74%], age 66±11 years) with ischemic heart disease (N=132, 52%) or ischemic valvular heart disease (N=121, 48%). As expected, SR origin was located at the superior intercaval region of the right atrium in 232 patients (92%). BB activation occurred via 1 wavefront from right-to-left (N=163, 64%), from the central part (N=18, 7%), or via multiple wavefronts (N=72, 28%). Left atrioventricular groove activation occurred via (1) BB: N=108, 43%; (2) pulmonary vein area: N=9, 3%; or (3) BB and pulmonary vein area: N=136, 54%; depending on which route had the shortest interatrial conduction time (P < 0.001). Ischemic valvular heart disease patients more often had central BB activation and left atrioventricular groove activation via pulmonary vein area compared with ischemic heart disease patients (N=16 [13%] versus N=2 [2%]; P=0.009 and N=86 [71%] versus N=59 [45%]; P < 0.001, respectively). Total activation times were longer in patients with AF (AF: 136±20 [92-186] ms; no AF: 114±17 [74-156] ms; P < 0.001), because of prolongation of right atrium (P=0.018) and BB conduction times (P < 0.001). Conclusions--Atrial excitation during SR is affected by underlying heart disease and AF, resulting in alternative routes for BB and left atrioventricular groove activation and prolongation of total activation times. Knowledge of atrial excitation patterns during SR and its electropathological variations, as demonstrated in this study, is essential to further unravel the pathogenesis of AF

Intraoperative inducibility of atrial fibrillation does not predict early postoperative atrial fibrillation

Background--Early postoperative atrial fibrillation (EPoAF) is associated with thromboembolic events, prolonged hospitalization, and development of late PoAF (LPoAF). It is, however, unknown if EPoAF can be predicted by intraoperative AF inducibility. The aims of this study are therefore to explore (1) the value of intraoperative inducibility of AF for development of both EPoAF and LPoAF and (2) the predictive value of de novo EPoAF for recurrence of LPoAF. Methods and Results--Patients (N=496, 75% male) undergoing cardiothoracic surgery for coronary and/or valvular heart disease were included. AF induction was attempted by atrial pacing, before extracorporeal circulation. All patients were on continuous rhythm monitoring until discharge to detect EPoAF. During a follow-up period of 2 years, LPoAF was detected by ECGs and Holter recordings. Sustained AF was inducible in 56% of patients. There was no difference in patients with or without AF before surgery (P=0.159), or between different types of surgery (P=0.687). In patients without a history of AF, incidence of EPoAF and LPoAF was 37% and 2%, respectively. EPoAF recurred in 58% patients with preoperative AF, 53% developed LPoAF. There were no correlations between intraoperative inducibility and EPoAF or LPoAF (P > 0.05). EPoAF was not correlated with LPoAF in patients without a history of AF (P=0.116), in contrast to patients with AF before surgery (P < 0.001). Conclusions--Intraoperative AF inducibility does not predict development of either EPoAF or LPoAF. In patients with AF before surgery, EPoAF is correlated with LPoAF recurrences. This correlation is absent in patients without AF before surgery

Dysrhythmias in patients with a complete atrioventricular septal defect: From surgery to early adulthood

Objective: Outcomes after surgical repair of complete atrioventricular septal defect (cAVSD) have improved.

QUest for the Arrhythmogenic Substrate of Atrial fibRillation in Patients Undergoing Cardiac Surgery (QUASAR Study): Rationale and Design

The heterogeneous presentation and progression of atrial fibrillation (AF) implicate the existence of different pathophysiological processes. Individualized diagnosis and therapy of the arrhythmogenic substrate underlying AF may be required to improve treatment outcomes. Therefore, this single-center study aims to identify t

Sinus Rhythm Conduction Properties across Bachmann's Bundle: Impact of Underlying Heart Disease and Atrial Fibrillation

Valvular heart disease (VHD) is a common risk factor for atrial fibrillation (AF). Conduction abnormalities (CA) during sinus rhythm (SR) across Bachmann’s bundle (BB) are associated with AF development. The study goal is to compare electrophysiological characteristics across BB during SR between patients with ischemic (IHD) and/or VHD either with or without ischemic heart disease ((I)VHD), with/without AF history using high-resolution intraoperative epicardial mapping. In total, 304 patients (IHD: n = 193, (I)VHD: n = 111) were mapped; 40 patients (13%) had a history of AF. In 116 patients (38%) there was a mid-entry site with a trend towards more mid-entry sites in patients with (I)VHD vs. IHD (p = 0.061), whereas patients with AF had significant more mid-entry sites than without AF (p = 0.007). CA were present in 251 (95%) patients without AF compared to 39 (98%) with AF. The amount of CA was comparable in patients with IHD and (I)VHD (p > 0.05); AF history was positively associated with the amount of CA (p < 0.05). Receiver operating characteristic (ROC) curve showed 85.0% sensitivity and 86.4% specificity for cut-off values of CA lines of respectively ≤ 6 mm and ≥ 26 mm. Patients without a mid-entry site or long CA lines (≥ 12 mm) were unlikely to have AF (sensitivity 90%, p = 0.002). There are no significant differences in entry-sites of wavefronts and long lines of CA between patients with IHD compared to (I)VHD. However, patients with AF have more wavefronts entering in the middle of BB and a higher incidence of long CA lines compared to patients without a history of AF. Moreover, in case of absence of a mid-entry site or long line of CA, patients most likely have no history of AF

Impact of the arrhythmogenic potential of long lines of conduction slowing at the pulmonary vein area

Background: Areas of conduction delay (CD) or conduction block (CB) are associated with higher recurrence rates after ablation therapy for atrial fibrillation (AF). Objective: Thus far, there are no reports on the quantification of the extensiveness of CD and CB at the pulmonary vein area (PVA) and their clinical relevance. Methods: Intraoperative high-density epicardial mapping of the PVA (interelectrode distance 2 mm) was performed during sinus rhythm in 268 patients (mean ± SD [minimum–maximum] 67 ± 11 [21–84] years) with and without preoperative AF. For each patient, extensiveness of CD (conduction velocity 17–29 cm/s) and CB (conduction velocity <17 cm/s) was assessed and related to the presence and type of AF. Results: CD and CB occurred in, respectively, 242 (90%) and 183 (68%) patients. Patients with AF showed a higher incidence of continuous conduction delay and block (CDCB) lines (AF: n = 37 [76%]; no AF: n = 132 [60%]; P =.046), a 2-fold number of lines per patient (CD: 7 [0–30] vs 4 [0–22], P <.001; CB: 3 [0–11] vs 1 [0–12], P =.003; CDCB: 2 [0–6] vs 1 [0–8], P =.004), and a higher incidence of CD or CB lines ≥6 mm and CDCB lines ≥16 mm (P =.011, P =.025, and P =.027). The extensiveness of CD, CB, and CDCB could not distinguish between the different AF types. Conclusion: Patients with AF more often present with continuous lines of adjacent areas of CD and CB, whereas in patients without AF, lines of CD and CB are shorter and more often separated by areas with normal intra-atrial conduction. However, a considerable overlap in the amount of conduction abnormalities at the PVA was observed between patients with a history of paroxysmal and persistent AF

The Effects of Valvular Heart Disease on Atrial Conduction During Sinus Rhythm

Different arrhythmogenic substrates for atrial fibrillation (AF) may underlie aortic valve (AV) and mitral valve (MV) disease. We located conduction disorders during sinus rhythm by high-resolution epicardial mapping in patients undergoing AV (n = 85) or MV (n = 54) surgery. Extent and distribution of conduction delay (CD) and block (CD) across the entire right and left atrial surface was determined from circa 1880 unipolar electrogram recordings per patient. CD and CB were most pronounced at the superior intercaval area (2.5% of surface, maximal degree 6.6%/cm2). MV patients had a higher maximal degree of CD at the lateral left atrium than AV patients (4.2 vs 2.3%/cm2, p = 0.001). A history of AF was most strongly correlated to CD/CB at Bachmann’s bundle and age. Although MV patients have more conduction disorders at the lateral left atrium, disturbed conduction at Bachmann’s bundle during sinus rhythm indicates the presence of atrial remodeling which is related to AF episodes

Dysrhythmia in Patients with Congenital Heart Disease and exploring the Role of Bachmann’s Bundle in Atrial Fibrillation

This thesis focuses on development and risk factors of dysthyrhmia, in particular atrial fibrillation, in patients with congenital heart disease. Furthermore, with oud unique epicarial mapping methods we investigated conduction across Bachmann's bundle, a bundle of parallel orientated muscle fibers between the right and left atrium, and it's potential role in development of atrial fibrillation

Usefulness of Fragmented QRS Complexes in Patients With Congenital Heart Disease to Predict Ventricular Tachyarrhythmias

Fragmented QRS complexes (fQRS) on 12-lead electrocardiogram are known predictors of ventricular tachyarrhythmia (VTA) in patients with coronary artery disease. There is limited knowledge of the clinical implications of fQRS in patients with congenital heart defects (CHD). Aims of this study were to examine (1) the occurrence of fQRS in patients with various types of CHD and (2) whether fQRS is associated with development of VTA. This study was designed as retrospective case-control study. Patients with CHD with VTA were included and matched with control patients of the same age, gender, and CHD type. Clinical data and fQRS were analyzed and compared. The initial VTA episode developed in 139 patients with CHD at a mean age of 39 +/- 14 years. Compared with controls (n = 219, age 38 +/- 13 years), QRS duration was longer in patients with VTA (110 vs 100 ms; p <0.01). Furthermore, fQRS was more frequently observed in patients with VTA in the last electrocardiogram before VTA (n = 73 [53%] vs n = 67 [31%]; p <0.001), especially in patients with sustained VTA (64%). Multiple conditional logistic regression demonstrated more fQRS (odds ratio [OR] 2.9, 95% confidence interval [CI] 1.5 to 5.8; p = 0.002), nonsystemic ventricular dysfunction (OR 5.1, 95% CI 2.1 to 12.4; p <0.001), and more prolonged QRS complexes (OR 2.8, 95% CI 1.3 to 6.2; p = 0.011) in patients with VTA. Therefore, the presence of fQRS on electrocardiogram may be a useful tool in daily clinical practice to identify patients at risk for developing VTA in patients with CHD, in addition to known predictors of VTA