Permanent His-bundle pacing in the right atrium in a patient with a Mobitz II atrioventricular block: a case presentation

Background This case report presents a patient diagnosed with sick sinus syndrome who was successfully treated with permanent His-bundle pacing (PHBP). Case presentation A 36-year-old man was transferred to our hospital due to recurrent syncope. He was diagnosed with sick sinus syndrome based on the 24-h Holter and a history of syncope. He was admitted to hospital and successfully treated with PHBP. The postoperative examination showed that the pacing rhythm, pacemaker pacing and perception function were normal. He was discharged without any complications after a successful pacemaker implantation. Conclusions We described a case in which PHBP may become an optimal approach to the management of patients with sick sinus syndrome. Right ventricular pacing has been attempted with inconsistent efficacy outcomes. HBP provides a promising alternative pacing option that might provide symptom resolution to patients with sick sinus syndrome.

Conduction System Pacing: Basis and Scope

Long-term right ventricular pacing (RVP) is associated with more cardiovascular death, atrial fibrillation (AF), thromboembolic complications and heart failure(HF). RVP often results in prolonged QRS duration(QRSd) and ventricular desynchronization. The ventricular desynchronization as a result of RVP leads to an increased risk of heart failure hospitalization (HFH) and AF, and this effect is dependent on cumulative percent ventricular paced ( % VP). In the sub-study from the MOST trial, it was evident that % VP >40% was associated with a 2.6-fold increased risk of HFH compared with pacing < 40% of the time despite preserved atrioventricular synchrony. Moreover this adverse effect of RVP induced ventricular desynchrony was more pronounced in patients with left ventricular ejection fraction( LVEF) of 40% or less resulting in increased death or HFH.

302 Impact of right ventricular pacing in patients with TAVI underwent permanent pacemaker implantation: the Pace-TAVI International Multicentre Study

Aims Permanent pacemaker implantation after transcatheter aortic valve implantation (TAVI) has emerged as a relevant issue, being more frequent than after surgery and the progressive shift towards low-risk patients stressed the importance to reduce the risk of complications that could impact patient’s long-term prognosis. Long-term right ventricular pacing has been related to an increased risk of electromechanical asynchrony, negative left-ventricular remodelling, atrial fibrillation and heart failure, but there is a lack of evidence regarding the prognostic impact on TAVI patients. The aim of this international multicentre study is to assess the impact of right ventricular pacing on prognosis of TAVI patients undergone pacemaker implantation after the procedure due to conduction disorders. Methods and results All the consecutive patients with severe aortic stenosis treated with TAVI and subsequently underwent pacemaker implantation in each participating centre were enrolled. Patients were divided into two subgroups according to the percentage of ventricular pacing (VP cut-off: 40%) at pacemaker interrogation. The primary endpoint was the composite of cardiovascular mortality and hospitalization for heart failure in subgroups based on the percentage of ventricular stimulation. All cause and cardiovascular mortality in the subgroups according to the percentage of ventricular pacing were the secondary endpoints. In total, 427 patients were enrolled, 153 patients with VP &lt; 40% and 274 with a with VP ≥ 40%. Patients with VP ≥ 40% were older (81.16 ± 6.4 years vs. 80.51 ± 6.8 years), with higher NYHA class, a lower EF (55.26 ± 12.2 vs. 57.99 ± 11.3 P = 0.03), an increased end diastolic ventricular volume (112.11 ± 47.6 vs. 96.60 ± 40.4, P = 0.005) and diameter (48.89 ± 9.7 vs. 45.84 ± 7.5 P = 0.01). A higher incidence of moderate post-procedural paravalvular leak was observed in patients with VP ≥ 40% (37.5% vs. 26.85%, P = 0.03). Ventricular pacing ≥40% was associated with a higher incidence of the composite primary endpoint of CV mortality and HF hospitalization (p at log rank test = 0.006, adjusted HR: 2.41; 95% CI: 1.03–5.6; P = 0.04). Patients with ventricular pacing ≥ 40% had also a higher risk of all-cause (p at log rank test = 0.03, adjusted HR = 1.57; 95% CI: 1.03–2.38; P = 0.03) and cardiovascular (p at log ank test =0.008, adjusted HR: 3.77; CI: 1.32–10.78; P = 0.006) mortality compared to patients with a VP &lt; 40%. Conclusions TAVI Patients underwent permanent pacemaker implantation after the procedure due to conduction disorders and with a VP ≥ 40% at follow-up are at increased risk of cardiovascular death and HF hospitalizations and of all-cause mortality compared to patients with a VP &lt; 40%. It is mandatory to reduce the percentage of ventricular pacing at follow-up when possible or consider left ventricular branch pacing and biventricular pacing in TAVI patients.

Conduction System Pacing for Post Transcatheter Aortic Valve Replacement Patients: Comparison With Right Ventricular Pacing

Introduction: For patients who develop atrioventricular block (AVB) following transcatheter aortic valve replacement (TAVR), right ventricular pacing (RVP) may be associated with adverse outcomes. We assessed the feasibility of conduction system pacing (CSP) in patients who developed AVB following TAVR and compared the procedural and clinical outcomes with RVP.Methods: Consecutive patients who developed AVB following TAVR were prospectively enrolled, and were implanted with RVP or CSP. Procedural and clinical outcomes were compared among different pacing modalities.Results: A total of 60 patients were enrolled, including 10 who were implanted with His bundle pacing (HBP), 20 with left bundle branch pacing (LBBP), and 30 with RVP. The HBP group had significantly lower implant success rate, higher capture threshold, and lower R-wave amplitude than the LBBP and RVP groups (p &lt; 0.01, respectively). The RVP group had a significantly longer paced QRS duration (153.5 ± 6.8 ms, p &lt; 0.01) than the other two groups (HBP: 121.8 ± 8.6 ms; LBBP: 120.2 ± 10.6 ms). During a mean follow-up of 15.0 ± 9.1 months, the LBBP group had significantly higher left ventricular ejection fraction (LVEF) (54.9 ± 6.7% vs. 48.9 ± 9.1%, p &lt; 0.05) and shorter left ventricular end-diastolic diameter (LVEDD) (49.7 ± 5.6 mm vs. 55.0 ± 7.7 mm, p &lt; 0.05) than the RVP group. While the HBP group showed trends of higher LVEF (p = 0.016) and shorter LVEDD (p = 0.017) than the RVP group. Four patients in the RVP group died—three deaths were due to progressive heart failure and one was due to non-cardiac reasons. One death in the LBBP group was due to the non-cardiac reasons.Conclusions: CSP achieved shorter paced QRS duration and better cardiac structure and function in post-TAVR patients than RVP. LBBP had a higher implant success rate and better pacing parameters than HBP.

Medium- and Long-Term Lead Stability and Echocardiographic Outcomes of Left Bundle Branch Area Pacing Compared to Right Ventricular Pacing

The long-term lead stability and echocardiographic outcomes of left bundle branch area pacing (LBBAP) are not fully understood. This study aimed to observe the mid-long-term clinical impact of LBBAP compared to right ventricular pacing (RVP). Consecutive bradycardia patients undergoing LBBAP or RVP were enrolled. Pacing and electrophysiological characteristics, echocardiographic measurements, and procedural complications were prospectively recorded at baseline and follow-up. LBBAP was successful in 376 of 406 patients (92.6%), while 313 patients received RVP. During a mean follow-up of 13.6 ± 7.8 months, LBBAP presented with similar pacing parameters and complications to RVP, except a significantly narrower paced QRS duration (115.7 ± 12.3 ms vs. 148.0 ± 18.0 ms, p < 0.001). In 228 patients with ventricular pacing burden >40%, LBBAP at last follow-up resulted in decreased left atrial diameter (LAD) (40.1 ± 8.5 mm vs. 38.5 ± 8.0 mm, p < 0.001) while RVP produced decreased left ventricular ejection fraction (62.7 ± 4.8% vs. 60.5 ± 6.9%, p < 0.001) when compared to baseline. After adjusting for age, the presence of atrial fibrillation, and other clinical factors, LBBAP was still associated with a decrease in LAD (−1.601, 95% CI −3.094–−0.109, p = 0.036). We conclude that LBBAP might result in more preserved echocardiographic outcomes than RVP.

Atrial fibrillation and stroke risk factors in patients with cardiac implantable electronic devices

Purpose. Determination the proportion and burden of new-onset atrial fibrillation (AF) in patients with cardiac implantable electronic devices (CIED) and without prior AF and assessing the incidence of risk factors for stroke in patients with AF.Methods. The medical history of 111 patients with CIED with remote monitoring function were analyzed. AF diagnosed by the device was interpreted by an arrhythmologist and cases of significant AF were selected. The group of patients with and without AF was compared for several factors. To clarify the influence of risk factors on the duration of AF, all AF cases were divided into 3 categories depending on the AF burden per day. The first group included patients with an AF burden per day of 0.1% or less (n=10, (45.5%)), the second - from 0.3% to 12.2% (n=7, (31.8%)), and the third group - with 100% (n=5, (22.7%)). Patients with a burden of 0.2%, 12.3-99.9% were absent.Results. Newly diagnosed AF was registered in 19.8% of cases. The risk of stroke among these patients was high - 2 [1; 3] points on the CHA2 DS2 -VASc for men, and 3 [2,75; 3,75] points for women. Hypertension of 2 and 3 degrees was recorded in all patients in the group with an AF burden of 100% per day. That significantly differed from the other 2 groups (p=0.043). In the group with an AF burden of 100%, the levels of NT-proBNP, D-dimer, and creatinine were significantly higher than in the other groups (p=0.037, p=0.031 and p=0.036, respectively). When analyzing the dependence of creatinine level on the presence of AF, the area under the ROC-curve was 0.653 with 95% confidence interval 0.528-0.779 (p=0.017). The proportion of right ventricular pacing in patients with ICD was higher in the group of patients with AF.Conclusion. AF occurs in 1/5 of patients with CIED. All patients with AF were potential candidates for anticoagulation due to their high risk of stroke. The daily burden of AF is positively correlated with the presence and degree of hypertension, as well as with markers of renal dysfunction, chronic heart failure, and thrombosis. Elevated creatinine levels are a predictor of AF.

Predictors of Right ventricular Pacing induced Left Ventricular dysfunction in Pacemaker Recipients with Preserved Ejection Fraction

Background Pacemaker (PM) has been an effective treatment in the management of patients with brady-arrhythmias. Chronic RV pacing may cause electrical and mechanical dyssynchrony which lead finally to reduced left ventricular ejection fraction (LVEF). This deterioration of LVEF has been defined as pacemaker induced cardiomyopathy (PICM). The incidence of PICM was described by many studies and ranged between 10% to 26%. The predictors for PICM have not been well studied. These studies were limited by variation in follow-up period and definition of PICM. Objective to study the incidence and predictors of PICM in patients who underwent pacemaker implantation in Ain shams University hospital. Patients and Methods This retrospective study included 160 patients who underwent single or dual chamber pacemaker implantation in Ain shams university hospital between 2010 and 2017 with the mean period 4.7±2.0 years. Implantable cardioverter defibrillator (ICD) and cardiac resynchronization therapy (CRT) patients were excluded. Individuals who had baseline transthoracic echocardiography (TTE) with normal LVEF ≥ 50% before implantation were included. Results This study included 160 patients who had single or dual chamber pacemaker implantation between 2010 and 2017. 45% were males and 55% were females, mean age was 55.5 years. It showed that the incidence of PICM is 7.5%. Wider native QRS durations, particularly &gt;140 ms (p &lt; 0.001), wider pQRS duration &gt;150 ms (p &lt; 0.001), Low normal ejection fraction &lt;56 % preimplantation (p = 0.023) and increased LVEDD&gt;53 mm and LVESD&gt;38 mm (p &lt; 0.001) are predictors for the development of PICM. Female gender was independent predictor for PICM (p = 0.058). There was no association between burden of right ventricular pacing (p = 0.782) or pacing site (p = 0.876) with the risk of development of left ventricular dysfunction. Conclusion The incidence of right ventricular pacing-induced left ventricular dysfunction is not uncommon, with an observed incidence of 7.5% in the current study. Wider native and paced QRS durations, Low normal ejection fraction (&lt; 56 %) pre-implantation and increased LVEDD /LVESD post implantation are the most important predictors for the development of PICM. List of abbreviations PM= pacemaker, RV= Right ventricle, PICM = pacemaker induced cardiomyopathy, TTE= transthoracic echocardiography, DM= Diabetes Mellitus, HTN= Hypertension, BMI= Body Mass index, pQRSd= Paced QRS duration, SWMA= segmental wall motion abnormality, AF= Atrial fibrillation, SSS= Sick sinus syndrome, CHB= Complete heart block, AVB= Atrioventricular block, LVEF = left ventricular ejection fraction, LVEDD= Left ventricular end diastolic diameter, LVESD= Left ventricular end systolic diameter, ms= milli second.