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Aims Left bundle branch pacing (LBBP) recently emerges as a novel pacing modality. We aimed to evaluate the feasibility and cardiac synchrony of permanent LBBP in bradycardia patients. Methods and results Left bundle branch pacing was successfully performed in 56 pacemaker-indicated patients with normal cardiac function. Left bundle branch pacing was achieved by penetrating the interventricular septum (IVS) into the left side sub-endocardium with the pacing lead. His-bundle pacing (HBP) was successfully performed in another 29 patients, 19 of whom had right ventricular septal pacing (RVSP) for backup pacing. The QRS duration, left ventricular (LV) activation time (LVAT), and mechanical synchrony using phase analysis of gated SPECT myocardial perfusion imaging were evaluated. Paced QRS duration in LBBP group was significantly shorter than that in RVSP group (117.8 ± 11.0 ms vs. 158.1 ± 11.1 ms, P < 0.0001) and wider than that in HBP group (99.7 ± 15.6 ms, P < 0.0001). Left bundle branch potential was recorded during procedure in 37 patients (67.3%). Left bundle branch pacing patients with potential had shorter LVAT than those without potential (73.1 ± 11.3 ms vs. 83.2 ± 16.8 ms, P = 0.03). Left bundle branch pacing patients with potential had similar LV mechanical synchrony to those in HBP group. R-wave amplitude and capture threshold of LBBP were 17.0 ± 6.7 mV and 0.5 ± 0.1 V, respectively at implant and remained stable during a mean follow-up of 4.5 months without lead-related complications. Conclusion Permanent LBBP through IVS is safe and feasible in bradycardia patients. Left bundle branch pacing could achieve favourable cardiac electrical and LV mechanical synchrony.

Low to moderate consumption of red wine reportedly has a relatively greater benefit than other alcoholic beverages in the prevention of atherosclerosis and coronary heart disease (CHD). This beneficial effect is increasingly attributed to the polyphenol resveratrol, present in red wine. In the present study, we investigated the effects of resveratrol and red wine on aggregation of platelets isolated from healthy, normotensive male volunteers and in rabbits with experimental hypercholesterolemia. Platelet aggregation rate (PAR) was measured using Born's method. The results showed that aggregation of platelets from healthy subjects induced in vitro by collagen (5 µg/ml), thrombin (0.33 units/ml), and ADP (4 µM) was significantly inhibited by 10-1000 µM resveratrol, in a concentration-dependent manner. Hypercholesterolemic rabbits showed enhanced ADP-induced platelet aggregation; the average PAR increased from 39.5±5.9% in normal animals to 61.0±7.0% in the high-cholesterol fed group (n=8, p<0.001). Resveratrol (4 mg/kg/day) inhibited ADP-induced platelet aggregation in vivo by maintaining the PAR at 35.7±6.3% (vs. 39.5±5.9% for control rabbits, n=8, p=0.228), but had no effect on serum lipid levels. Similarly platelet aggregation in hypercholesterolemic rabbits was also inhibited when animals received intragastrically Chinese red wine (with or without alcohol, 4 ml/kg/day). These results suggest that resveratrol can inhibit platelet aggregation both in vitro and in vivo, which conceivably could be one of the mechanisms by which this red wine polyphenol exerts its cardioprotective effects.

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BackgroundLeft bundle branch area pacing (LBBAP) was reported to improve cardiac function by correcting complete left bundle branch block (CLBBB). Our study aimed to compare the efficacy of LBBAP and biventricular pacing (BIVP) in heart failure patients with CLBBB.MethodsTen patients prospectively underwent LBBAP (LBB‐CRT group) and 30 patients received BIVP (BIV‐CRT group) were matched using propensity score matching. LBBAP was achieved by the trans‐interventricular septum method. Echocardiography, electrocardiogram, NYHA classification, and blood B‐type natriuretic peptide concentration were evaluated at preimplantation and at 6‐month follow up. CRT response was defined as at least 15% decrease in left ventricular end‐systolic volume.ResultsIn the LBB‐CRT group, CLBBB were successfully corrected by LBBAP with no complications. QRS duration (QRSd) significantly decreased after implantation in both groups, and the decrease of QRSd in the LBB‐CRT group was significantly greater than that in the BIV‐CRT group (60.80 ± 20.09 vs. 33.00 ± 21.48 ms, p = .0009). The echocardiographic measurements including left ventricular end‐diastolic diameter, left ventricular end‐systolic diameter, and left ventricular ejection fraction significantly improved after 6 months in both groups. The response rate was significantly higher in LBB‐CRT group than BIV‐CRT group (100.00% vs. 63.33%, p = .038). The percentage of patients in New York Heart Association classification Grades I and II was significantly higher in the LBB‐CRT group compared with that in the BIV‐CRT group (median 1.5 vs. 2.0, p = .029) at 6‐month follow‐up.ConclusionsIt is effective and safe to correct CLBBB with LBBAP in heart failure patients. Compared with BIVP, LBBAP can better optimize electrical synchrony and improve cardiac function.