Left bundle branch pacing (LBBP) provides synchronized contraction of ventricles and overcomes the limitation of His bundle pacing (HBP). The pacing lead is placed deep inside the septum 1-1.5 cm apical to the distal His bundle region. The criteria for capture of left bundle branch (LBB) have been proposed but it has never been validated. LBB potentials may not be demonstrable in all patients. Premature ventricular complexes (PVC) are often noted while positioning the lead in the interventricular septum. The morphology of the PVCs depends on the depth of the lead in the septum. We describe a novel method for lead placement to capture LBB by monitoring the morphology and duration of PVCs in four patients with different pacing indications. Rapid rotations were stopped immediately on observing a PVC with narrow QRS duration and qR (right bundle branch delay) pattern in lead V1. LBB potential and non-selective to selective LBB capture could be demonstrated after placing the lead. PVC guided lead placement would help in final positioning of the lead, avoid perforation into left ventricle cavity and to confirm conduction system capture.
Cardiac pacing is the only effective therapy for patients with symptomatic brady-arrhythmia. Traditional right ventricular apical pacing causes electrical and mechanical dyssynchrony resulting in left ventricular dysfunction, recurrent heart failure and atrial arrhythmias. Physiological pacing activates the normal cardiac conduction thereby providing synchronized contraction of ventricles. Though His bundle pacing (HBP) acts as an ideal physiological pacing modality, it is technically challenging and associated with troubleshooting issues during follow up. Left bundle branch pacing (LBBP) has been suggested as an effective alternative to overcome the limitations of HBP as it provides low and stable pacing threshold, lead stability and correction of distal conduction system disease. This paper will focus on the implantation technique, troubleshooting, clinical implications and a review of published literature of LBBP
Background: Left bundle branch pacing (LBBP) provides physiological pacing at low and stable threshold. The safety and efficacy of LBBP in elderly population is unknown. Objectives: Our study was designed to assess the safety, efficacy and electrophysiological parameters of LBBP in octogenarian (≥80 years) population Methods: All octogenarians requiring permanent pacemaker implantation for symptomatic bradycardia and heart failure were prospectively enrolled. Echocardiography, electrocardiography and pacing parameters were recorded. Results: LBBP was successful in 10 out of 11 patients. Mean age 82.1 ± 2.5 yrs. Male 7 patients. Follow up duration 4.7 months (range1-7months). Indication for pacing included atrioventricular (AV) block 5 patients, Left bundle branch block (LBBB) with low ejection fraction (EF) 4 patients, sinus node dysfunction in 1. LB lead placement fluoroscopic time was 17.9 minutes. QRS duration reduced from 145.9 ±27.7ms at baseline to 107.1 ±9.5ms after LBBP (p value0.00001) LV ejection fraction increased from 47.6 % to 55.9 % after LBBP (p value0.017). Pacing threshold was 0.58 ± 0.22V and sensed R wave 17.35 ± 6.5mV and it remained stable during follow up. LBBB with low EF patients also showed similar reduction in QRS duration along with improvement in LVEF. No major complications noted Conclusion: LBBP is a safe and effective strategy (91% acute success) of physiological pacing in elderly patients. LBBP also provided effective resynchronization therapy in our small group of elderly patients. The pacing parameters remained stable over a period of 7 months follow up.
Background: His bundle pacing (HBP) has evolved as the most physiological form of pacing but associated with limitations. Recently left bundle branch pacing (LBBP) is emerging as an effective alternative strategy for HBP. Objectives: Our study was designed to assess the feasibility, efficacy, electrophysiological parameters and mid-term outcomes of LBBP in Indian population Methods: All patients requiring permanent pacemaker implantation for symptomatic bradycardia and heart failure were prospectively enrolled. Echocardiography, QRS duration, pacing parameters, Left bundle(LB) potentials, paced QRS duration and peak left ventricular activation time (pLVAT) recorded. Results: LBBP was successful in 93 out of 99 patients (94% acute success). Mean age 62.6 ± 13 yrs. Male 59%, diabetes 69%, coronary artery disease 65%. Follow up duration 4.8 months (range1-12 months). Indication for pacing were atrioventricular (AV) block 43%, cardiac resynchronization therapy 40%, AV node ablation 4%. LB potential noted in 37 patients (40%). QRS duration reduced from 144.38 ±34.6ms at baseline to 110.8 ±12.4ms after LBBP (p value 0.0001). Pacing threshold was 0.59 ± 0.22V and sensed R wave 14.14 ± 7.19 mV and it remained stable during follow up. Lead depth in the septum was 9.62 mm. LV ejection fraction increased from 44.96 % to 53.3 % after LBBP (p value 0.0001). One died due to respiratory tract infection on follow up Conclusion: LBBP is a safe and effective strategy (94% acute success) of physiological pacing. The pacing parameters remained stable over a period of 12 months follow up. LBBP can effectively overcome the limitations of HBP