Conduction system pacing (CSP) is being increasingly adopted as a more physiological alternative to right ventricular and biventricular pacing. Since the 2021 European Society of Cardiology pacing guidelines, there has been growing evidence that this therapy is safe and effective. Furthermore, left bundle branch area pacing was not covered in these guidelines due to limited evidence at that time. This Clinical Consensus Statement provides advice on indications for CSP, taking into account the significant evolution in this domain.

• Klíčová slova
• Biventricular pacing, Cardiac resynchronization therapy, Conduction system pacing, His bundle pacing, Indications, Left bundle branch area pacing,
• MeSH
• akční potenciály MeSH
• kardiologie * normy   MeSH
• kardiostimulace umělá * normy   škodlivé účinky   metody   MeSH
• konsensus MeSH
• lidé MeSH
• převodní systém srdeční * patofyziologie   MeSH
• společnosti lékařské MeSH
• srdeční arytmie * terapie   patofyziologie   diagnóza   MeSH
• srdeční frekvence MeSH
• výsledek terapie MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• směrnice pro lékařskou praxi MeSH
• Geografické názvy
• Evropa MeSH

INTRODUCTION: Left bundle branch area pacing (LBBAP) comprises pacing at the left ventricular septum (LVSP) or left bundle branch (LBBP). The aim of the present study was to investigate the differences in ventricular electrical heterogeneity between LVSP, LBBP, right ventricular pacing (RVP) and intrinsic conduction with different dyssynchrony measures using the ECG, vectorcardiograpy, ECG belt, and Ultrahigh frequency (UHF-)ECG. METHODS: Thirty-seven patients with a pacemaker indication for bradycardia or cardiac resynchronization therapy underwent LBBAP implantation. ECG, vectorcardiogram, ECG belt and UHF-ECG signals were recorded during RVP, LVSP and LBBP, and intrinsic activation. QRS duration (QRSd) was measured from the ECG, QRS area was calculated from the vectorcardiogram, LV activation time (LVAT) and standard deviation of activation time (SDAT) from ECG belt and electrical dyssynchrony (e-DYS16) from UHF-ECG. RESULTS: Both LVSP and LBBP significantly reduced ventricular electrical heterogeneity as compared to underlying LBBB and RV pacing in terms of QRS area (p < .001), SDAT (p < .001), LVAT (p < .001) and e-DYS16 (p < .001). QRSd was only reduced as compared to RV pacing(p < .001). QRS area was similar during LBBP and normal intrinsic conduction, e-DYS16 was similar during LVSP and normal intrinsic conduction, whereas SDAT was similar for LVSP, LBBP and normal intrinsic conduction. For all these variables there was no significant difference between LVSP and LBBP. CONCLUSION: Both LVSP and LBBP resulted in a more synchronous LV activation than LBBB and RVP. Especially LBBP resulted in levels of LV synchrony comparable to normal intrinsic conduction.

• Klíčová slova
• bradycardia pacing, cardiac resynchronization therapy, conduction system pacing, dyssynchrony, left bundle branch area pacing,
• MeSH
• akční potenciály * MeSH
• blokáda Tawarova raménka patofyziologie   terapie   diagnóza   MeSH
• bradykardie patofyziologie   terapie   diagnóza   MeSH
• časové faktory MeSH
• elektrofyziologické techniky kardiologické MeSH
• elektrokardiografie MeSH
• funkce levé komory srdeční * MeSH
• Hisův svazek * patofyziologie   MeSH
• kardiostimulace umělá * MeSH
• lidé středního věku MeSH
• lidé MeSH
• mezikomorová přepážka * patofyziologie   MeSH
• prediktivní hodnota testů * MeSH
• senioři nad 80 let MeSH
• senioři MeSH
• srdeční frekvence * MeSH
• srdeční resynchronizační terapie MeSH
• vektorkardiografie * metody   MeSH
• výsledek terapie MeSH
• Check Tag
• lidé středního věku MeSH
• lidé MeSH
• mužské pohlaví MeSH
• senioři nad 80 let MeSH
• senioři MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• srovnávací studie MeSH

In contrast to left bundle branch pacing, the criteria for left ventricular septal pacing (LVSP) were never validated. LVSP is usually defined as deep septal deployment of the pacing lead with a pseudo-right bundle branch morphology in V1. The case report describes an implant procedure during which this definition of LVSP was fulfilled in four of five pacing locations within the septum, with the shallowest of them present in less than 50% of the septal thickness. The case highlights the need for a more precise definition of LVSP.

• Publikační typ
• časopisecké články MeSH
• kazuistiky MeSH

Biventricular pacing (Biv) and left bundle branch area pacing (LBBAP) are methods of cardiac resynchronization therapy (CRT). Currently, little is known about how they differ in terms of ventricular activation. This study compared ventricular activation patterns in left bundle branch block (LBBB) heart failure patients using an ultra-high-frequency electrocardiography (UHF-ECG). This was a retrospective analysis including 80 CRT patients from two centres. UHF-ECG data were obtained during LBBB, LBBAP, and Biv. Left bundle branch area pacing patients were divided into non-selective left bundle branch pacing (NSLBBP) or left ventricular septal pacing (LVSP) and into groups with V6 R-wave peak times (V6RWPT) < 90 ms and ≥ 90 ms. Calculated parameters were: e-DYS (time difference between the first and last activation in V1-V8 leads) and Vdmean (average of V1-V8 local depolarization durations). In LBBB patients (n = 80) indicated for CRT, spontaneous rhythms were compared with Biv (39) and LBBAP rhythms (64). Although both Biv and LBBAP significantly reduced QRS duration (QRSd) compared with LBBB (from 172 to 148 and 152 ms, respectively, both P < 0.001), the difference between them was not significant (P = 0.2). Left bundle branch area pacing led to shorter e-DYS (24 ms) than Biv (33 ms; P = 0.008) and shorter Vdmean (53 vs. 59 ms; P = 0.003). No differences in QRSd, e-DYS, or Vdmean were found between NSLBBP, LVSP, and LBBAP with paced V6RWPTs < 90 and ≥ 90 ms. Both Biv CRT and LBBAP significantly reduce ventricular dyssynchrony in CRT patients with LBBB. Left bundle branch area pacing is associated with more physiological ventricular activation.

• Klíčová slova
• Biv CRT, Heart failure, LBBAP, UHF-ECG, Ventricular synchrony,
• Publikační typ
• časopisecké články MeSH

AIMS: The field of conduction system pacing (CSP) is evolving, and our aim was to obtain a contemporary picture of European CSP practice. METHODS AND RESULTS: A survey was devised by a European CSP Expert Group and sent electronically to cardiologists utilizing CSP. A total of 284 physicians were invited to contribute of which 171 physicians (60.2%; 85% electrophysiologists) responded. Most (77%) had experience with both His-bundle pacing (HBP) and left bundle branch area pacing (LBBAP). Pacing indications ranked highest for CSP were atrioventricular block (irrespective of left ventricular ejection fraction) and when coronary sinus lead implantation failed. For patients with left bundle branch block (LBBB) and heart failure (HF), conventional biventricular pacing remained first-line treatment. For most indications, operators preferred LBBAP over HBP as a first-line approach. When HBP was attempted as an initial approach, reasons reported for transitioning to utilizing LBBAP were: (i) high threshold (reported as >2 V at 1 ms), (ii) failure to reverse bundle branch block, or (iii) > 30 min attempting to implant at His-bundle sites. Backup right ventricular lead use for HBP was low (median 20%) and predominated in pace-and-ablate scenarios. Twelve-lead electrocardiogram assessment was deemed highly important during follow-up. This, coupled with limitations from current capture management algorithms, limits remote monitoring for CSP patients. CONCLUSIONS: This survey provides a snapshot of CSP implementation in Europe. Currently, CSP is predominantly used for bradycardia indications. For HF patients with LBBB, most operators reserve CSP for biventricular implant failures. Left bundle branch area pacing ostensibly has practical advantages over HBP and is therefore preferred by many operators. Practical limitations remain, and large randomized clinical trial data are currently lacking.

• Klíčová slova
• CSP, HBP, LBBAP, Survey,
• MeSH
• blokáda Tawarova raménka diagnóza   terapie   MeSH
• funkce levé komory srdeční MeSH
• lidé MeSH
• převodní systém srdeční MeSH
• srdeční arytmie terapie   MeSH
• srdeční resynchronizační terapie * MeSH
• srdeční selhání * diagnóza   terapie   MeSH
• tepový objem fyziologie   MeSH
• výsledek terapie MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• randomizované kontrolované studie MeSH

AIMS: Permanent transseptal left bundle branch area pacing (LBBAP) is a promising new pacing method for both bradyarrhythmia and heart failure indications. However, data regarding safety, feasibility and capture type are limited to relatively small, usually single centre studies. In this large multicentre international collaboration, outcomes of LBBAP were evaluated. METHODS AND RESULTS: This is a registry-based observational study that included patients in whom LBBAP device implantation was attempted at 14 European centres, for any indication. The study comprised 2533 patients (mean age 73.9 years, female 57.6%, heart failure 27.5%). LBBAP lead implantation success rate for bradyarrhythmia and heart failure indications was 92.4% and 82.2%, respectively. The learning curve was steepest for the initial 110 cases and plateaued after 250 cases. Independent predictors of LBBAP lead implantation failure were heart failure, broad baseline QRS and left ventricular end-diastolic diameter. The predominant LBBAP capture type was left bundle fascicular capture (69.5%), followed by left ventricular septal capture (21.5%) and proximal left bundle branch capture (9%). Capture threshold (0.77 V) and sensing (10.6 mV) were stable during mean follow-up of 6.4 months. The complication rate was 11.7%. Complications specific to the ventricular transseptal route of the pacing lead occurred in 209 patients (8.3%). CONCLUSIONS: LBBAP is feasible as a primary pacing technique for both bradyarrhythmia and heart failure indications. Success rate in heart failure patients and safety need to be improved. For wider use of LBBAP, randomized trials are necessary to assess clinical outcomes.

• Klíčová slova
• Complications, Conduction system pacing, Distal capture, Left bundle branch pacing, Left bundle fascicular pacing, Left ventricular septal pacing,
• MeSH
• blokáda Tawarova raménka terapie   etiologie   MeSH
• bradykardie terapie   etiologie   MeSH
• elektrokardiografie metody   MeSH
• Hisův svazek * MeSH
• kardiostimulace umělá škodlivé účinky   metody   MeSH
• lidé MeSH
• senioři MeSH
• srdeční selhání * MeSH
• výsledek terapie MeSH
• Check Tag
• lidé MeSH
• senioři MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• multicentrická studie MeSH
• pozorovací studie MeSH

BACKGROUND: Left bundle branch area pacing (LBBAP) has recently been introduced as a novel physiological pacing strategy. Within LBBAP, distinction is made between left bundle branch pacing (LBBP) and left ventricular septal pacing (LVSP, no left bundle capture). OBJECTIVE: To investigate acute electrophysiological effects of LBBP and LVSP as compared to intrinsic ventricular conduction. METHODS: Fifty patients with normal cardiac function and pacemaker indication for bradycardia underwent LBBAP. Electrocardiography (ECG) characteristics were evaluated during pacing at various depths within the septum: starting at the right ventricular (RV) side of the septum: the last position with QS morphology, the first position with r' morphology, LVSP and-in patients where left bundle branch (LBB) capture was achieved-LBBP. From the ECG's QRS duration and QRS morphology in lead V1, the stimulus- left ventricular activation time left ventricular activation time (LVAT) interval were measured. After conversion of the ECG into vectorcardiogram (VCG) (Kors conversion matrix), QRS area and QRS vector in transverse plane (Azimuth) were determined. RESULTS: QRS area significantly decreased from 82 ± 29 µVs during RV septal pacing (RVSP) to 46 ± 12 µVs during LVSP. In the subgroup where LBB capture was achieved (n = 31), QRS area significantly decreased from 46 ± 17 µVs during LVSP to 38 ± 15 µVs during LBBP, while LVAT was not significantly different between LVSP and LBBP. In patients with normal ventricular activation and narrow QRS, QRS area during LBBP was not significantly different from that during intrinsic activation (37 ± 16 vs. 35 ± 19 µVs, respectively). The Azimuth significantly changed from RVSP (-46 ± 33°) to LVSP (19 ± 16°) and LBBP (-22 ± 14°). The Azimuth during both LVSP and LBBP were not significantly different from normal ventricular activation. QRS area and LVAT correlated moderately (Spearman's R = 0.58). CONCLUSIONS: ECG and VCG indices demonstrate that both LVSP and LBBP improve ventricular dyssynchrony considerably as compared to RVSP, to values close to normal ventricular activation. LBBP seems to result in a small, but significant, improvement in ventricular synchrony as compared to LVSP.

• Klíčová slova
• bradycardia pacing, cardiac resynchronization therapy, left bundle branch area pacing,
• Publikační typ
• časopisecké články MeSH