Clinical Outcomes of Left Bundle Branch Area Pacing in Comparison with Right Ventricular Septal Pacing in Patients with High Ventricular Pacing Ratio ≥40%

Figures & data

Figure 1 The implantation procedure of LBBaP. (A) Fluoroscopic image of 4-pole RV electrode and axillary vein position, RBB potential were recorded (white circle shows). (B) HB potential (white circle shows) was identified at IEGM and fluoroscopic image of the 3830 lead and sheath position were recorded as a mark. (C) PVC (white circle shows) emerging from endometrial surface of the left ventricular septum was observed during the lead implantation and fluoroscopic image of LBB area was confirmed.

Abbreviations: HB, His bundle; IEGM, intracardiac electrogram; LBBaP, left bundle branch area pacing; LBB, left bundle branch; PVC, premature ventricular contraction; RBB, right bundle branch; and RV, right ventricular.

Figure 2 Twelve-lead electrocardiogram and electrogram during LBBaP. (A) Intrinsic rhythm in LBBaP. The change in the notch morphology in lead V 1 (red arrow) during rotating the lead from the right side to the left side of the septum (B-D). (E) Left bundle branch potential. The S-PLVAT in lead V5 with low and high output (F and G).

Abbreviations: LBBaP, left bundle branch area pacing; and S-PLVAT, stimulus to peak left ventricular activation time.

Figure 3 Postoperative images of LBBaP (A and B) and RVSP (D and E), contrast injection through the sheath in LBBaP (C) and RVSP (F).

Abbreviations: IVS, interventricular septum; LBBaP, left bundle branch area pacing; and RVSP, right ventricular septal pacing.

Table 1 Baseline Patient Characteristics and Procedure Outcomes

Groups	RVSP (n = 21)	LBBaP (n = 33)	P value
Demographics
Age (years)	68.14±11.66	73.67±11.87	0.099
Male sex, n (%)	11 (52.4%)	21 (63.6%)	0.412
Comorbidities
Hypertension, n (%)	12 (57.1%)	19 (57.6%)	0.975
Diabetes, n (%)	2 (9.5%)	6 (18.2%)	0.631
Coronary artery disease, n (%)	3 (14.3%)	11 (33.3%)	0.215
Paroxysmal or persistent AF, n (%)	6 (28.6%)	6 (18.2%)	0.371
Diagnosis
SSS, n (%)	2 (9.5%)	3 (9.1%)	0.975
AVB, n (%)	15 (71.4%)	30 (90.9%)	0.134
AF with slow ventricular rate, n (%)	4 (19.1%)	0 (0%)	0.019
LBBB, n (%)	2 (9.5%)	5 (15.2%)	0.853
RBBB, n (%)	3 (14.3%)	0 (0%)	0.054
LBB potential, n (%)		23 (69.7%)
Pacing-R wave peak of V5 lead (ms)		73.18±5.23
Procedure duration (min)	93.19±8.70	120.82±11.46	<0.0001
Fluoroscopy dose (mGy)	53.38±9.02	79.36±8.79	<0.0001

Abbreviations: AF, atrial fibrillation; AVB, atrium ventricular block; LBB, left bundle branch; LBBB, left bundle branch block; LBBaP, left bundle branch area pacing; RBBB, right bundle branch block; RVSP, right ventricular septum pacing; SSS, sick sinus syndrome.

Table 2 Comparison of QRSd and Echocardiographic Parameters Between the LBBaP and RVSP Groups Before and After Pacemaker Implantation

		RVSP	LBBaP	P-value
QRSd (ms)	Baseline	113.48±21.80	113.58±21.22	0.987
	Post implantation	132.90±14.78^ᵻ	110.88±7.37	<0.0001
	At last follow-up	133.11±14.17*	110.91±7.12	<0.0001
RAD (mm)	Baseline	36.48±4.64	36.73±5.29	0.859
	At last follow-up	36.83±3.54	38.00±5.47	0.420
LVEDD (mm)	Baseline	50.62±7.10	47.48±4.69	0.056
	At last follow-up	51.28±7.58	47.09±4.47	0.017
LVEF (%)	Baseline	63.57±9.98	64.97±6.15	0.526
	At last follow-up	60.44±9.28	64.81±5.49	0.041
IVMD (ms)	Baseline	30.05±12.82	30.82±10.77	0.813
	At last follow-up	40.28±6.97*	28.16±4.76	<0.0001
SPWMD (ms)	Baseline	46.95±36.36	44.27±33.96	0.784
	At last follow-up	97.94±12.77*	43.68±26.41	<0.0001

Notes: ^ᵻP < 0.0001 post implantation vs baseline. * P < 0.0001 at last follow-up vs baseline.

Abbreviations: IVMD, interventricular mechanical delay; LBBaP, left bundle branch area pacing; LVEDD, left ventricular end-diastolic diameter; LVEF, left ventricular ejection fraction; QRSd, QRS duration; RAD, right atrial diameter; RVSP, right ventricular septum pacing; SPWMD, septal-posterior wall motion delay.

Table 3 Changes in Pacing Parameters at Follow-Ups

		RVSP	LBBaP	P-value
Capture threshold (V @0.4 ms)	At implantation	0.71±0.30	0.60±0.20	0.103
	1-month	0.62±0.21	0.62±0.15	0.929
	At last follow-up	0.60±0.23	0.60±0.23	0.921
R wave amplitude (mV)	At implantation	12.36±2.99	11.79±3.29	0.523
	1-month	15.41±5.78^a	13.67±2.82^a	0.152
	At last follow-up	15.54±4.20^a	14.70±2.84^a	0.403
Ventricular impedance (Ohms)	At implantation	817.14 ± 104.98	830.61±120.60	0.676
	1-month	667.45±115.58^a	627.25±76.23^a	0.136
	At last follow-up	548.17±89.27^a,b	583.59±69.87^a	0.126

Notes: ^aP < 0.05 at 1-month or at last implantation vs at implantation. ^bP < 0.05 at last follow-up vs 1-month.

Abbreviations: LBBaP, left bundle branch area pacing; and RVSP, right ventricular septum pacing.

Figure 4 Change trend of Capture threshold (A), R-wave amplitude (B), and Pacing impedance (C) between two groups at implantation, 1 month and at last follow-up. LBBaP, left bundle branch area pacing; and RVSP, right ventricular septum pacing.