A randomized comparison of HBP versus RVP: Effect on left ventricular function and biomarkers of collagen metabolism

Background: Right ventricular pacing (RVP) can result in pacing-induced cardiomyopathy (PICM). It is unknown whether specific biomarkers reflect differences between His bundle pacing (HBP) and RVP and predict a decrease in left ventricular function during RVP. Aims: To compare the effect of HBP and RVP on the LV ejection fraction (LVEF) and to study how they affect serum markers of collagen metabolism. Methods: Ninety-two high-risk PICM patients were randomized to HBP or RVP. Their clinical characteristics, echocardiography, and serum levels of TGF-β1, MMP-9, ST2-IL, TIMP-1, and Gal-3 were studied before and six months after pacemaker implantation. Results: Fifty-three patients were randomized to HBP and 39 patients to RVP. HBP failed in 10 patients, which crossed over to the RVP group. Patients with RVP had significantly lower LVEF compared to HBP after six months of pacing (−5% and −4% in as-treated and intention-to-treat analysis, respectively). Levels of TGF-β1 after 6 months were lower in HBP than RVP (mean difference −6 ng/ml; P = 0.009) and preimplant Gal-3 and ST2-IL levels were higher in RVP patients with a decline in the LVEF ≥ 5% compared to those with a decline of < 5% (mean difference 3 ng/ml and 8 ng/ml; P = 0.02 for both). Conclusion: In high-risk PICM patients, HBP was superior to RVP in providing more physiological ventricular function, as reflected by higher LVEF and lower levels of TGF-β1. Among RVP patients, LVEF declined more in those with higher baseline Gal-3 and ST2-IL levels than those with lower levels

Close Proximity of Left Anterior Descending Artery to the Right Ventricular Lead Apparently Implanted into the Mid-septum

Right ventricular (RV) mid-septal pacing should have fewer negative effects on left ventricular function compared to apical pacing. However, targeting the mid-septum may be technically challenging since it is usually done with two-dimensional fluoroscopy. The rotation of the heart and various shapes of the RV make it difficult to assess, whether the lead is really anchored in the septum. Many leads, apparently anchored in the septum, are in fact anchored in the anterior wall or anteroseptal groove, and some can get anchored in close proximity to the left anterior descending artery (LAD). We report three cases from our series of 51 patients, in whom the RV lead thought to be implanted in the mid-septum was in fact anchored in close proximity of LAD when assessed using computed tomography

Left bundle branch area pacing outcomes : the multicentre European MELOS study

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