Electrogram-only guided approach to His bundle pacing with minimal fluoroscopy: A single-center experience.

INTRODUCTION: His bundle pacing (HBP) is the most physiological pacing. The standard technique based on fluoroscopic approach might be challenging and fluoro consuming. Targeting the His guided exclusively by the electrical signals could enable a precise lead implant, thus reducing fluoroscopy time (FT) and X-ray dose, desirable both for patients and operators. The aim of the study is to evaluate the feasibility, efficacy, and safety both acutely and at 30 days of the electrogram (EGM)-guided HBP with minimal or no fluoroscopy. METHODS AND RESULTS: Between October and December 2018, 41 consecutive patients underwent EGM-guided HBP. Successful HBP was obtained in 39 (95%) patients, (30 males, 78 ± 10 years). Selective HBP (S-HBP) was achieved in 23 (59%), nonselective HBP (NS-HBP) in 16 (41%) patients. The final HBP lead position was reached in 31 (79.4%) patients without fluoroscopy, only guided by electrical signals. In eight patients a minimal fluoroscopy (mean, 8 seconds) has been required. The sheath's cutting and the slack of the lead were routinely performed under fluoroscopy. No difference was observed in FT for HBP lead placement in S-HBP and NS-HBP (mean, 8.1 ± 25 vs 7.5 ± 20 seconds, P = .8; median value 0 vs 0 seconds). No differences were observed in FT for the entire procedure, total dose area product and total procedural time in S-HBP and NS-HBP. Lead dislodgement occurred in one (2.6%) patient 1 day after the procedure. CONCLUSIONS: HBP could be performed safely and efficiently using the EGMs, with minimal or no fluoroscopy. Fluoroscopy was required during sheath removal and atrial lead placement.

Long term performance and safety of His bundle pacing: A multicenter experience.

INTRODUCTION: Several single-center short-term studies have demonstrated the feasibility, safety, and positive clinical outcomes of permanent His bundle pacing (HBP). We performed a retrospective study to evaluate long-term technical and safety performances of HBP in a large population of pacemaker patients from two different centers. METHODS AND RESULTS: The analysis includes 844 patients (345 female, mean age = 75 ± 9 years) who underwent successful permanent HBP for pacemaker indications from 2004 to 2016. The main endpoints were long term electrical performances including pacing threshold, sensing, impedance, and freedom from pacing related complications. The pacing indication was AV Block in 348 (41.2%) patients, sinus node disease in 147 (17.4%), any bradycardia indication in patients with atrial fibrillation in 335 (39.7%) patients and need for cardiac resynchronization therapy in 14 (1.7%) patients. Mean pacing capture thresholds and sensed R waves were 1.6 V and 5.8 mV, respectively at implant and 2.0 V and 6.1 mV at chronic follow-up. During the median follow up of 3 years (interquartile range = 1-6 years), HBP was free of any complication in 91.6% of patients. In the first 368 patients, HBP was achieved using a deflectable curve delivery system, while in 476 using the fixed curve sheath. A significant difference was found in the thresholds (2.4 ± 1.0 V and 1.7 ± 1.1 V, P < .001, respectively) and complications (11.9% and 4.2%, P < .001, respectively) between the two groups. CONCLUSIONS: Permanent HBP was safe and effective during long-term follow-up. The fixed curved delivery sheath offered significantly better electrical parameters and reliability over time. The results of this multicenter study are consistent with recent studies.

The risk of atrial fibrillation during right ventricular pacing.

AIMS: Right ventricular pacing adversely affects left atrial (LA) structure and function that may trigger atrial fibrillation (AF). This study compares the occurrence of persistent/permanent AF during long-term Hisian area (HA), right ventricular septal (RVS), and right ventricular apex (RVA) pacing in patients with complete/advanced atrioventricular block (AVB). METHODS AND RESULTS: We collected retrospective data from 477 consecutive patients who underwent pacemaker implantation for complete/advanced AVB. Ventricular pacing leads were located in the HA, RVS, and RVA in 148, 140, and 189 patients, respectively. The occurrence of persistent/permanent AF was observed in 114 (23.9%) patients (follow-up 58.5 ± 26.5 months). Hisian area groups presented a lower rate of AF occurrence (16.9%) compared with RVS and RVA groups (25.7 and 28.0%, respectively), P = 0.049. Cox's proportional hazard model was used to estimate HR. The risk of persistent/permanent AF was significantly lower in the patients paced from HA compared with those paced from RVA, HR = 0.28 (95% CI 0.16-0.48, P = 0.0001). The RVS and RVA pacing groups showed a similar AF risk: HR 1.04 (95% CI 0.66-1.64, P = 0.856). Other independent predictors of persistent/permanent AF occurrence included previous (before device implantation) paroxysmal AF (HR = 4.08; 95% CI 3.15-7.31, P = 0.0001), LA diameter, and age, whereas baseline bundle-branch block was associated with a lower risk of AF occurrence (HR = 0.56; 95% CI 0.35-0.81, P = 0.003). CONCLUSIONS: HA pacing compared with RVA or RVS pacing seems to be associated with a lower risk of persistent/permanent AF occurrence. The risk of persistent/permanent AF was similar in the RVA vs. RVS groups.

In-hospital follow-up of implantable cardioverter defibrillator and pacemaker carriers: patients' inconvenience and points of view. A four-hospital Italian survey.

AIMS: The increasing volume of pacemaker (PM) and implantable cardioverter defibrillator (ICD) implants and problems related to their functioning have highlighted the issue of device follow-ups. Patients' convenience regarding device visits has been little investigated. This work aims at surveying patients' efforts in attending the in-office PM/ICD follow-ups and at evaluating their expectations. METHODS AND RESULTS: In four Italian referral centres, over a 3-month period, a 20-point questionnaire was completed by all consecutive patients at in-hospital PM/ICD visits. In total, 1109 questionnaire/patients were evaluated. Pacemakers were 68%, ICDs 16%, and cardiac resynchronizations (CRTs) (PM + ICD) 16%; 38% were females; mean age was 75 ± 11 years. Almost all were scheduled visits. There was frequent reprogramming and clinical examination, even after 6 months from implant. Perceived inconvenience for the in-office follow-up was relevant in 35% of cases; attitudes towards remote monitoring were positive in 88% of cases. Inter-group analysis showed some significant difference: PM patients were older and more frequently female; ICD carriers were younger, had the highest rate of clinical evaluation, a longer journey time, and the most positive opinion about remote follow-up. Cardiac resynchronization patients had a longer waiting time and the lowest inconvenience. Overall inconvenience was independently predicted by increasing age, lengthy travelling times, and being accompanied; favourable opinions about remote monitoring were predicted by overall inconvenience, and, in ICD carriers only, by lack of clinical examination. CONCLUSIONS: Patients' perceptions of in-hospital PM/ICD visits were affected by age and by journey modalities. Individual factors seem to affect both opinions about in-office visits and expectations towards a possible remote follow-up.

Implantation technique of His bundle pacing.

His bundle pacing (HBP) preserves physiological ventricular synchrony, with clinical benefits particularly evident when a high percentage of ventricular pacing is required. First experiences with standard leads and manually shaped stylets produced the impression that HBP is highly complex and time-consuming. However, with dedicated leads and sheaths, reliable HBP can be achieved in routine clinical practice. Implantation success in more than 90% of patients can be reached with current technology and has been shown to be reliable and effective, both at implantation and during long-term follow-up. At the same time, fluoroscopy and total procedural time can be reduced. New customized technologies will continue to improve the implant success rate and system performance. Large randomized trials will prove the long-term clinical benefits of HBP definitively and may render HBP the first choice in patients requiring ventricular pacing.

Ventricular-arterial coupling in patients with heart failure treated with cardiac resynchronization therapy: may we predict the long-term clinical response?

OBJECTIVE: To evaluate the effects of cardiac resynchronization therapy (CRT) on ventricular-arterial coupling (VAC) in patients with refractory congestive heart failure (HF), left bundle brunch block, and sinus rhythm. BACKGROUND: The ratio between arterial elastance (Ea) and left ventricular end-systolic elastance (Ees), the so-called VAC, defines the efficiency of the myocardium in pumping blood. METHODS: Seventy-eight patients were studied with echocardiography before CRT, and 1 year later. End-systolic elastance was calculated according to the method of Chen. Arterial elastance (ratio of the systolic pressure to the stroke volume), end-systolic volume (ESV), and quality of life (QoL) (Minnesota Living with Heart Failure Questionnaire) were assessed at the baseline and after 1 year. Patients with a reduction>15% of ESV or a decrease>33% in QoL score were considered responders to CRT. RESULTS: QRS duration and interventricular delay were significantly reduced with CRT compared with baseline (156+/-2 vs. 195+/-3 ms, P<0.001; and 25+/-2 vs. 55+/-3 ms, P<0.001, respectively). Arterial elastance/Ees decreased significantly on CRT (2.47+/-1.48 vs. 1.41+/-0.87, P<0.0001). The lowering of Ea/Ees was congruent to a decrease in intraventricular delay (83.1+/-55.7 vs. 28.4+/-49.5 ms, P<0.0001) and an increase in ejection fraction (26+/-6.3 vs. 36.9+/-8.0%, P<0.0001). Responders to CRT were 74 and 71% of the overall patient population, considering as endpoint QoL or ESV, respectively. The analysis of VAC showed a baseline cut-off value of 2, above which 88% and 69% of patients responded to CRT, considering as endpoint QoL or ESV, respectively. CONCLUSIONS: The non-invasive assessment of VAC may be proposed as an immediate, easy, and optimal tool for quantifying the effect of CRT in patients with HF.

A feasible approach for direct his-bundle pacing using a new steerable catheter to facilitate precise lead placement.

INTRODUCTION: Much clinical evidence has shown that right ventricular (RV) apical pacing is detrimental to left ventricular function. Preservation of the use of the His-Purkinje (H-P) system may be ideal in heart block that is restricted to the AV node, but may be of no benefit when H-P disease exists. AIM: To investigate the feasibility of direct His-bundle pacing (DHBP) using a new system consisting of a steerable catheter and a new 4.1 F screw-in lead. METHOD: Between May and December 2004, 26 patients (19 male, mean age: 77 +/- 5 years) with a standard pacemaker (PM) indication and preserved His-bundle conduction were enrolled and DHBP was attempted. RESULTS: DHBP was achieved in 24 patients (92%); two patients were paced in the His area, but the paced QRS morphology and duration were different from the native QRS. The mean time for lead positioning was 19 +/- 17 minutes, the mean fluoroscopy time was 11 +/- 8 minutes, and the total procedure time (skin-to-skin including positioning of a quadripolar diagnostic catheter for His recording) was 75 +/- 18 minutes. In DHBP pacing, the acute pacing threshold was 2.3 +/- 1.0 V at a pulse duration of 0.5 msec, and the sensed potentials were 2.9 +/- 2.0 mV. At a 3-month follow-up examination, the same QRS duration and morphology recorded on implantation were observed in all patients. The pacing threshold was 2.8 +/- 1.4 V, and sensed potentials were 2.5 +/- 1.8 mV; the sensing configuration was changed from bipolar to unipolar in 6 patients to resolve undersensing issues. No major complications were observed. CONCLUSIONS: This feasibility study shows that DHBP can be accomplished with a new system consisting of a steerable catheter and an active fixation lead in 92% of the patients in whom it was attempted.

Implantation of left ventricular leads using a telescopic catheter system.

BACKGROUND: Implantation procedures for cardiac resynchronization therapy (CRT) remain challenging with regard to coronary sinus (CS) cannulation and left ventricular (LV) lead positioning. Technologic advances in catheter design may facilitate CS cannulation and LV lead placement. AIMS: To evaluate two different telescoping dual-catheter systems, RAPIDO Guiding Catheter System (Group R) and RAPIDO ADVANCE Guiding Catheter System (Group A) (Guidant Inc., St. Paul, MN, USA), during implantation of a CRT device. METHODS: Seventy-four consecutive patients randomly received a CRT device using the R or A system. RESULTS: An LV lead was successfully implanted in 74 patients (100%). (1) Median times for CS cannulation in groups R and A were 0.3 minutes (range from 0.05 to 14 minutes) and 0.5 minutes (range from 0.05 to 9 minutes), respectively (P = NS). (2) Median times for LV lead placement were 8 minutes (range from 0.8 to 100 minutes) and 3.5 minutes (range from 0.25 to 30 minutes), respectively, for groups R and A (P = 0.032). (3) Median total fluoroscopy times were 12.33 minutes (range from 5 to 70 minutes) and 14.33 minutes (range from 6 to 53 minutes) for groups R and A, respectively (P = NS). (4) Median procedural times for CRT implantation were 80 minutes (range from 40 to 200 minutes) and 75 minutes (range from 45 to 180 minutes) (P = NS) in groups R and A, respectively. There were no major complications. CONCLUSION: CS cannulation and LV lead placement with a telescopic dual-catheter system is a safe and feasible approach that may reduce fluoroscopy and overall CRT implantation times. Our observations suggest that the RAPIDO ADVANCE System is faster than the RAPIDO System in terms of median time for LV lead positioning.