European Society of Cardiology (ESC) clinical consensus statement on indications for conduction system pacing, with special contribution of the European Heart Rhythm Association of the ESC and endorsed by the Asia Pacific Heart Rhythm Society, the Canadian Heart Rhythm Society, the Heart Rhythm Society, and the Latin American Heart Rhythm Society

Figures

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  Figure 1. Relationship between asynchronous ventricular activation leading to reduced pump function. P–V, pressure volume. Reproduced, with permission, from Vernooy et al.14

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  Figure 2. Computer-simulated three-dimensional activation maps following different pacing strategy and their corresponding segmental activation time in bullseye form. Reproduced with permission from Meiburg et al.38

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  Figure 3. Examples of ventricular dyssynchrony assessed by ultra-high-frequency ECG (sampled at 5 KHz and evaluating the 150–1000 hz spectrum of the QRS complex, with V1–V8 electrodes placed in standard positions). In each of the UHF-ECG maps, time is visualized on the x-axis, and chest leads are visualized on the y-axis. Local activations under the specific leads are connected by a black line. The difference between V1 and V8 activations (white circles) indicates interventricular electrical dyssynchrony, whereas the width of the coloured band informs of local activation duration. Note that all CSP methods, as well as LVSP, are associated with less interventricular dyssynchrony than RVSP. CSP, conduction system pacing; ECG, electrocardiogram; HBP, His bundle pacing; LBBP, left bundle branch pacing; LVSP, left ventricular septal pacing; RVSP, right ventricular septal pacing.

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  Figure 4. Electrocardiographic imaging (ECGi) with examples of LVAT shortening and change of activation pattern with CSP and BiVP. All 3 cases show long LVAT with delayed activation of the left ventricle (blue or purple during intrinsic rhythm with left bundle branch block or with right ventricular pacing. With CSP and BiVP, all showed decrease in LVAT and faster activation of the left ventricle (green or red). (A) Maps with an imageless ECGi technology and (B) and (C) maps with ECGi that requires computed tomography. BiVP, biventricular pacing; CSP, conduction system pacing; LVAT, left ventricular activation time.

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  Figure 5. Summary of CSP indications in AVB. AVB, atrioventricular block; BiVP, biventricular pacing; CSP, conduction system pacing; HBP, His bundle pacing; HOT/LOT-CRT, His-optimized or left bundle-optimized cardiac resynchronization therapy; LBBAP, left bundle branch area pacing; LVEF, left ventricular ejection fraction; MVP, minimized ventricular pacing; RVP, right ventricular pacing.

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  Figure 6. Haemodynamic consequences of AF and potential benefits of the ‘pace-and-ablate’ therapy. AF, atrial fibrillation; ATP, adenosine triphosphate; AV, atrioventricular; CSP, conduction system pacing; EF, ejection fraction; QOL, quality of life; RAS, renin-angiotensin system. Reproduced, with permission, from Joza et al.140.

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  Figure 7. Indications for CSP in patients scheduled for AVNA. AVNA, atrioventricular nodal ablation; BiVP, biventricular pacing; CSP, conduction system pacing; HBP, His bundle pacing; HOT/LOT-CRT, His-optimized or left bundle-optimized cardiac resynchronization therapy; LBBAP, left bundle branch area pacing; LVEF, left ventricular ejection fraction; RVP, right ventricular pacing.

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  Figure 8. Indication for CSP-CRT. BiV-CRT, biventricular pacing cardiac resynchronization therapy; BiVP, biventricular pacing; CSP, conduction system pacing; HOT/LOT-CRT, His-optimized or left bundle-optimized cardiac resynchronization therapy; LBBB, left bundle branch block; LVEF, left ventricular ejection fraction; PICM, pacing-induced cardiomyopathy.

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  Figure 9. Schematic illustration of ventricular activation wavefronts BiV-CRT, HOT-CRT, and LOT-CRT. Approximate activation by the right ventricular lead is indicated in blue, by the conduction system pacing lead in green, and by the coronary sinus lead in red. Adapted with permission from Zweerink et al.225 BiV-CRT, biventricular pacing cardiac resynchronization therapy; BiVP, biventricular pacing; CS, coronary sinus pacing; HBP, His bundle pacing; HOT-CRT, His bundle pacing-optimized cardiac resynchronization therapy; LOT-CRT, left bundle branch-optimized cardiac resynchronization therapy; RBBB, right bundle branch block; RVP, right ventricular pacing.

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  Figure 10. Superior electrical resynchronization with LOT-CRT compared with BiVP. Note the presence of QRS notching with BiVP and LBBP, which disappears with LOT-CRT. BiVP, biventricular pacing; LBBP, left bundle branch pacing; LOT-CRT, left bundle branch-optimized cardiac resynchronization therapy.

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  Figure 11. Summary of ongoing RCTs on conduction system pacing. The background colours of the study names represent different types of study endpoints: light grey indicates soft endpoints, dark grey indicates hard endpoints, and medium grey indicates a combination of soft and hard endpoints. AF, atrial fibrillation; AVNA, atrioventricular node ablation; BiVP, biventricular pacing; CRT, cardiac resynchronization therapy; CSP, conduction system pacing; HBP, His bundle pacing; HFrEF, heart failure with reduced ejection fraction; HFmrEF, heart failure with mid-range ejection fraction; HFprEF, heart failure with preserved ejection fraction; LBBAP, left bundle branch area pacing; LBBP, left bundle branch pacing; LOT-CRT, left bundle branch-optimized cardiac resynchronization therapy; LV, left ventricle; LVEF, left ventricular ejection fraction; OMT, optimal medical therapy; RVP, right ventricular pacing.