Is Conduction System Pacing a Valuable Alternative to Biventricular Pacing for Cardiac Resynchronization Therapy?

Cardiac resynchronization therapy (CRT) significantly improves clinical outcomes in patients with ventricular systolic dysfunction and dyssynchrony. Biventricular pacing (BVP) has a class IA recommendation for patients with symptomatic heart failure with reduced ejection fraction (HFrEF) and left bundle branch block (LBBB). However, approximately 30% of patients have a poor therapeutic response and do not achieve real clinical benefit. Pre-implant imaging, together with tailored programming and dedicated device algorithms, have been proposed as possible tools to improve success rate but have shown inconsistent results. Over the last few years, conduction system pacing (CSP) is becoming a real and attractive alternative to standard BVP as it can restore narrow QRS in patients with bundle branch block (BBB) by stimulating and recruiting the cardiac conduction system, thus ensuring true resynchronization. It includes His bundle pacing (HBP) and left bundle branch area pacing (LBBAP). Preliminary data coming from small single-center experiences are very promising and have laid the basis for currently ongoing randomized controlled trials comparing CSP with BVP. The purpose of this review is to delve into the emerging role of CSP as an alternative method of achieving CRT. After framing CSP in a historical perspective, the pathophysiological rationale and available clinical evidence will be examined, and crucial technical aspects will be discussed. Finally, evidence gaps and future perspectives on CSP as a technique of choice to deliver CRT will be summarized.

Transvenous lead extraction of lumenless 3830 pacing lead in conduction system pacing: a single-center experience

BACKGROUND

The Medtronic SelectSecure Model 3830 lumenless lead (Medtronic, Inc., Minneapolis, MN) is commonly used for conduction system pacing (CSP). However, with this increased use, the potential need for transvenous lead extraction (TLE) also will increase. While extraction of endocardial 3830 leads is rather well described especially in pediatric and adult congenital heart disease population, there is very limited data on extraction of CSP leads. In the present study, we reported our preliminary experience on TLE of CSP leads and provided technical considerations.

METHODS

The study population comprised 6 consecutive patients (67% male; mean age 70 ± 22 years) with CSP leads (3830 leads), including left bundle branch pacing (LBBP) lead (n = 3) and His pacing lead (n = 3) undergoing TLE. Overall target leads were 17. The mean implant duration time of CSP leads was 97 ± 90 months [range 8-193).

RESULTS

Manual traction was successful in 2 cases and mechanical extraction tools were required in the remaining cases. Sixteen leads (94%) were completely extracted, whereas incomplete removal was observed in one lead (6%) among 1 patient. Of note, in the only lead incompletely removed, we observed retention of < 1-cm remnant of lead material consisting of the screw of 3830 LBBP lead into the interventricular septum. No failure of lead extraction was reported and no major complications occurred.

CONCLUSIONS

Our findings demonstrated that at an experienced center the success of TLE of chronically implanted CSP leads is high in the absence of major complications also when mechanical extraction tools are needed.

Comparative Study of Bioactive Compounds and Biological Activities of Five Rose Hip Species Grown in Sicily

Nowadays, research on plant extracts has attracted increasing interest. The aim of this study was to compare phenolic profile, vitamin C, and carotenoid content, as well as the biological activities of five different rose species, including Rosa canina, R. corymbifera, R. micrantha, R. rubiginosa, and R. rugosa. These species had different morphological characteristics, with R. rugosa showing higher size of flower petals and higher weight of hips. The highest vitamin C content was found in hip extracts of R. rubiginosa and R. rugosa, which also showed the highest carotenoid amount. R. corymbifera showed the highest phenolic content. No significant antimicrobial activity of extracts containing phenolic compounds against different indicator strains could be detected. Cell monolayer integrity was not affected by treatments with the above-mentioned extracts of R. canina, R. micrantha, and R. rugosa at different concentrations for up to 24 h, while those of R. rubiginosa and R. corymbifera affected intestinal permeability at the highest concentration tested. The partial least squares regression analysis generated a predictive model correlating phenolic compounds with cell monolayer integrity, suggesting a relevant role for catechin, quercitrin, and p-coumaric acid. In conclusion, this study highlights how rose hips belonging to different species can have a diverse phenolic profile, differently influencing intestinal monolayer integrity.

Conduction system pacing in difficult cardiac anatomies: Systematic approach with the 3D electroanatomic mapping guide

INTRODUCTION

Restoring physiological cardiac electrical activity in patients with conduction disease can be crucial for the survival and quality of life. Conduction system pacing (CSP) is a valuable option, although it is limited by technical challenges in difficult anatomies. 3D electroanatomical mapping (3D-EAM) can support CSP ensuring high electro-anatomical precision and low fluoroscopy.

OBJECTIVES

We evaluated the feasibility and effectiveness of a systematic 3D-EAM use to guide CSP in difficult anatomical scenarios (highly dilated atria, congenital cardiomyopathies, failed biventricular implants (BiV) and pacing-induced cardiomyopathy (PICM)).

METHODS

Forty-three consecutive patients (27 males, 75 ± 10 years old) with standard pacing indications and difficult anatomical scenarios were included. The right atrium, His cloud, and atrio-ventricular septum were reconstructed by 3D-EAM. The His bundle (HB) was the initial target, while left bundle branch area pacing (LBBAP) was aimed at in case of unsatisfactory parameters, sub-optimally paced QRS, or impossibility of reaching the HB.

RESULTS

CSP was successful in 37 (86%) patients (15 HBP; 22 LBBAP). Mean mapping, fluoroscopy, and procedural times were 18 ± 7 min, 7 ± 5 min, 98 ± 47 min, respectively. The mean pacing threshold, R wave sensing, and pacing impedance of CSP lead were 1.2 ± 0.5V@0.5ms, 11.4 ± 6.2 mV, 736 ± 306 Ω, respectively. Baseline and paced QRS were 139 ± 38 ms and 114 ± 23 ms, respectively. No procedural complications were observed.

CONCLUSIONS

3D-EAM allowed the accurate definition of the His cloud and high ventricular septum and effectively guided CSP. It facilitated CSP in complex anatomies, with a procedural success rate of 86%. The results were satisfactory and reproducible, with acceptable fluoroscopy and procedural times.

Modeling chronic oil pollution from ships

Stochastic simulations of virtual oil spills from ships were performed for the Adriatic Sea over 2017-2020, applying the European Marine Observation and Data Network vessel densities as a proxy for starting locations of operational spillage. The MEDSLIK-II oil spill model was run using high-resolution currents provided by the Copernicus Marine Service and the European Centre for Medium-Range Weather Forecasts winds. Chronic exposure to operational oil spills was reported in terms of hazard indices for five vessel groups: pleasure and passenger ships, cargo and service vessels, the fishing fleet, tankers, and other ships. The northernmost Adriatic expectedly showed the highest hazard values, including the areas of Trieste and Venice, where cargo and service ships were the dominant polluters. The Croatian coastal waters were more chronically polluted than the Italian coastal waters; the predominant contribution was from coastwise pleasure and passenger ships.

The Fate of Chlorophylls in Alkali-Treated Green Table Olives: A Review

This paper reviews the current knowledge regarding modifications to chlorophylls during the processing of green table olives treated with alkali. Particular attention is given to the pheophytinization reactions (substitution of Mg2+ by 2H+ in the chlorophyll chromophore group) that can take place because of pH and/or temperature changes and the possible sequential substitution of the 2H+ with Cu2+ within the chlorophyll porphyrin ring. These reactions may have a direct impact on the commercial value of olive productions as some naturally forming Cu-chlorophylls complexes (i) are identical to strictly forbidden colorants for table olives (E141) and (ii) have been identified as responsible for the unwelcome appearance of the so-called green staining alteration (characterized by bluish-green zones distributed over the olive skin of the drupes).

The weakest point of cardiac resynchronization therapy: new technologies facing old terminology

Patients with symptomatic heart failure (HF) and left bundle branch block (LBBB) are currently treated with biventricular pacing (BiV) which has a Class IA recommendation. Given the possibility to re-establish the inter and intra-ventricular synchrony, BiV is commonly referred to as cardiac resynchronization therapy (CRT). This wording is widely utilized and over time the terms BiV and CRT have become interchangeable. Conduction system pacing (CSP) is emerging as a valid therapeutic opportunity to obtain CRT restoring the native conduction via the Purkinje network. Therefore the acronym CRT is no longer synonymous with BiV only but could also refer to CSP. A terminology update is needed to include the resource of CSP to ensure better communication among all the stakeholders involved in managing recipients of cardiac devices and should be a fundamental step in advancing the quality of patient care. Making use of the NBG code to describe the implantable cardiac device would ease such terminology update, since only the first three positions of the five letters NBG code are commonly utilized, while the last two are rarely used.

The Fate of the Chlorophyll Derivatives in Olives Preserved and/or Packaged in Presence of Exogenous Copper

Chlorophyll pigments are thought to be responsible for the highly appreciated green color of unfermented Castelvetrano-style table olives, but no studies have considered the effects of a controlled addition of copper during storage or packaging at the industrial level. For this purpose, chlorophyll derivatives were analyzed in Nocellara cultivar table olives debittered industrially using the Castelvetrano method, via means of HPLC and MS analyses, following the addition of copper in alkaline brines stored at 4 °C for 3 months in 220 L barrels, and during the subsequent storage in acid brines in commercial 400 g packages at 4 °C for up to 18 months. The presence of copper in storage or in packaging brines both contributed significantly to maintaining the green color of the olives, which was associated with a specific pattern of chlorophyll derivatives, as evidenced by principal component analysis. Notably, re-greening was rapidly achievable also for olives that had yellowed for 18 months at a copper concentration below the limit of EU legislation. Finally, by means of PCA, we also demonstrated that a short-term thermic treatment can work as an accelerated predictive tool in determining the fate of chlorophyll derivatives.

The PhysioVP-AF study, a randomized controlled trial to assess the clinical benefit of physiological ventricular pacing vs. managed ventricular pacing for persistent atrial fibrillation prevention in patients with prolonged atrioventricular conduction: design and rationale

AIMS

In patients with prolonged atrioventricular (AV) conduction and pacemaker (PM) indication due to sinus node disease (SND) or intermittent AV-block who do not need continuous ventricular pacing (VP), it may be difficult to determine which strategy to adopt. Currently, the standard of care is to minimize unnecessary VP by specific VP avoidance (VPA) algorithms. The superiority of this strategy over standard DDD or DDD rate-responsive (DDD/DDDR) in improving clinical outcomes is controversial, probably owing to the prolongation of the atrialventricular conduction (PR interval) caused by the algorithms. Conduction system pacing (CSP) may offer the most physiological-VP approach, providing appropriate AV conduction and preventing pacing-induced dyssynchrony.

METHODS AND RESULTS

PhysioVP-AF is a prospective, controlled, randomized, single-blind trial designed to determine whether atrial-synchronized conduction system pacing (DDD-CSP) is superior to standard DDD-VPA pacing in terms of 3-year reduction of persistent-AF occurrence. Cardiovascular hospitalization, quality-of-life, and safety will be evaluated. Patients with indication for permanent DDD pacing for SND or intermittent AV-block and prolonged AV conduction (PR interval > 180 ms) will be randomized (1:1 ratio) to DDD-VPA (VPA-algorithms ON, septal/apex position) or to DDD-CSP (His bundle or left bundle branch area pacing, AV-delay setting to control PR interval, VPA-algorithms OFF). Approximately 400 patients will be randomized in 24 months in 13 Italian centres.

CONCLUSION

The PhysioVP-AF study will provide an essential contribution to patient management with prolonged AV conduction and PM indication for sinus nodal disease or paroxysmal 2nd-degree AV-block by determining whether CSP combined with a controlled PR interval is superior to standard management that minimizes unnecessary VP in terms of reducing clinical outcomes.

Unraveling the Effects of Carotenoids Accumulation in Human Papillary Thyroid Carcinoma

Among the thyroid cancers, papillary thyroid cancer (PTC) accounts for 90% of the cases. In addition to the necessity to identify new targets for PTC treatment, early diagnosis and management are highly demanded. Previous data indicated that the multivariate statistical analysis of the Raman spectra allows the discrimination of healthy tissues from PTC ones; this is characterized by bands typical of carotenoids. Here, we dissected the molecular effects of carotenoid accumulation in PTC patients by analyzing whether they were required to provide increased retinoic acid (RA) synthesis and signaling and/or to sustain antioxidant functions. HPLC analysis revealed the lack of a significant difference in the overall content of carotenoids. For this reason, we wondered whether the carotenoid accumulation in PTC patients could be related to vitamin A derivative retinoic acid (RA) biosynthesis and, consequently, the RA-related pathway activation. The transcriptomic analysis performed using a dedicated PCR array revealed a significant downregulation of RA-related pathways in PTCs, suggesting that the carotenoid accumulation in PTC could be related to a lower metabolic conversion into RA compared to that of healthy tissues. In addition, the gene expression profile of 474 PTC cases previously published in the framework of the Cancer Genome Atlas (TGCA) project was examined by hierarchical clustering and heatmap analyses. This metanalysis study indicated that the RA-related pathways resulted in being significantly downregulated in PTCs and being associated with the follicular variant of PTC (FV-PTC). To assess whether the possible fate of the carotenoids accumulated in PTCs is associated with the oxidative stress response, the expression of enzymes involved in ROS scavenging was checked. An increased oxidative stress status and a reduced antioxidant defense response were observed in PTCs compared to matched healthy thyroids; this was possibly associated with the prooxidant effects of high levels of carotenoids. Finally, the DepMap datasets were used to profile the levels of 225 metabolites in 12 thyroid cancer cell lines. The results obtained suggested that the high carotenoid content in PTCs correlates with tryptophan metabolism. This pilot provided novel possible markers and possible therapeutic targets for PTC diagnosis and therapy. For the future, a larger study including a higher number of PTC patients will be necessary to further validate the molecular data reported here.

His Bundle Pacing: My Experience, Tricks, and Tips

His Bundle Pacing (HBP) is a form of physiologic pacing achieved through implantation of a pacing electrode into the His bundle. HBP began 20 years ago without any dedicated tools. As specific tools became available HBP quickly spread and proved to be a viable alternative to traditional right ventricle pacing. HBP is reliable and effective in preserving the physiologic ventricular synchrony with clinical benefits particularly evident when a high percentage of pacing is required. Unipolar signals from the lead tip guide the implant. 3D electroanatomical mapping could further assist the procedure.

Conduction system pacing with Selectra 3D Sheath: Technical Results

Funding Acknowledgements

Type of funding sources: None.

Background

Conduction system pacing (CSP) allows physiological electrical activation. The Selectra3D sheath is a new tool able to guide the lead implantation on the His Bundle (HBP) or on the left bundle branch (LBBP). It does exist in 3 different shapes (40-S, 55-M, 65-L).

Objective

To evaluate the effectiveness of different Selectra3D introducers for CSP, considering the procedural success, stability of electrical parameters or need for implant revision at medium-term follow-up.

Methods and results

Selectra3D was used in 113 CSP procedures between Nov 2019 and Nov 2021. Mean patients age was 80±6 years, 54% males. Pacing indications were: AV block 52.2%, slow AF 12.4%; SND 12.4%, ablate&pace 5.3%, implant revision 0.9%, cardiomyopathy 16.8%. Mean EF was 40±15%. Single chamber PM was implanted in 4.8% pts, dual chamber PM in 57.1% pts while 26.2% and 11.9% pts received CRT-P and CRT-D devices respectively. Stylet-driven lead was used in 75 pts, fixed screw lead in 38 pts. HBP was obtained in 34% pts, LBBP in 55% pts, HBP+LBBP in 3% pts, while 8% cases were CSP implant failure (7 lead implanted in the septum; 2 in the coronary sinus). Selectra3D was the first delivery used during the procedure in 88% of cases (55-M in 76%; 40-S in 9%; 65-L in 3%), while was the second tool (after failure of the first delivery utilised) in the other pts. The first Selectra3D utilized during each implant was able to complete the procedure in 64% of cases, while in the other pts a second different tool was required to complete the implant. The Selectra3D 55-M was the mostly used and was able to reach the final position in most cases. In dilated atria the 65-L curve was preferred, while when the target point was more proximal the 45-S curve was the best choice. The baseline QRS duration was 135 ± 34 ms and the paced QRS duration was 113 ± 18 ms (P 0.003). The electrical parameters were optimal with sensing 8.7 ± 8 mV; impedance 562 ± 133 ohm; threshold 0.97 ± 0.47 V. During a median follow-up of 178 [34-402] days, 7 lead dislodgement (3 HBP and 4 LBBP) were recorded. All the others showed stability of the electrical parameters.

Conclusion

The Selectra3D introducers effectively supports CSP ensuring procedural success rate&gt;90%. The 55-M curve fits for most of the anatomies, the 45-S curve allows to reach more proximal target, the 65-L curve more distal target in dilated atria. The electrical parameters were optimal at implant and remained stable during follow-up. 6% lead dislodgement were recorded.

Left Bundle Branch Pacing: procedural outcomes using different sheaths

Funding Acknowledgements

Type of funding sources: None.

Background

Left Bundle Branch Pacing (LBBP) ensures physiologic ventricular activation. Growing experiences are rising on its applicability . Different tools available allow successful implant in different cardiac anatomies.

Objective

To analyse implant success rate and acute electrical parameters in LBBP guided by C315 fixed curve sheath or Selectra3D sheath.

Methods

151 patients (mean age 79.8±8.3 years; 51% males) received LBBP. Pacing indication: AV block 50%, SND 12%, slow AF12%, ablate&pace 9%; HF 14%, revision of previous lead 1%. Coronary disease was present in 31%; hypertension in 93%, diabetes in 30%, severe valvular disease in 5%, persistent AF in 31% pts. Average QRS duration was 136±34 ms. Basal mean EF 52±12%. Different criteria for successful LBBP were analyzed (table 1).

Results

The lead was successfully implanted in the left bundle in 97.3% pts. In 60.5% pts guided by the C315 Medtronic fixed curve sheath while in 39.5% pts by the Selectra3D (40-S, 55-M, 65-L) Biotronik sheaths. 93 (63%) pts received 3830 fixed screw lead, 51 (35%) pts received Solia S 60 stylet-driven lead and 3 (2%) patients received Tendril 58 cm stylet-driven lead. All different criteria analysed to define successful LBBP were comparable in the C315 and Selectra 3D group (table 1). In 61% pts LBBP was the first choice, in 39% LBBP was aimed after unsatisfactory HBP (His threshold&gt;2V or paced QRS&gt;140 ms). The LBBP lead was connected to the RV port in 67% DR and 18% SR PMs; to the LV port in the 22 CRT devices. Mean fluoroscopy time was 10±6 min including implant of all leads, without differences between implants. Electrical parameters were highly favourable in all patients (mean threshold 0.73±0.27V and mean sensing 11±5.8 mV) without differences between the 2 sheaths. Pacing impedance was significantly lower in the Selectra 3D group. Paced QRS duration was 114±15 ms (112±14 vs 116±16 ms; P 0.180). Implant failure were 4 (2 due to severe tricuspid regurgitation and 2 to severe dilated atria).

Conclusion

LBBP is highly reliable in clinical practice. The different sheath available lead to successfully perform the implant in different cardiac anatomies. In our experience there was no differences in technical acute outcome between implant guided by C315 Medtronic sheath and Selectra3D Biotronik sheath.

P80 PROGNOSTIC IMPACT OF NEW ONSET ATRIAL FIBRILLATION AFTER SINGLE OR DOUBLE STENT LEFT MAIN BIFURCATION PCI

Objective

Incidence and prognostic value of new onset atrial fibrillation (NOAF) after single versus double stent strategy in bifurcation Left Main (LM) disease has not been yet investigated.

Methods

We retrospectively analysed the procedural and medical data of patients referred to our center for complex LM bifurcation disease, treated using Cross–over provisional stenting, T or T–and–Protrusion (TAP), Culotte, and Nano–inverted–T (NIT) techniques between January 1st, 2008 to May 1st 2018. Multivariate Cox–regression analysis was used to assess the role of different stent strategies, adjusted for confounders, on the risk of NOAF during the follow–up period.

Results

Five hundred and two patients (316 males, mean age 70.3±12.8 years, mean Syntax score 31.6±6.3) were evaluated. At a mean follow–up of 37.1±10.8 months (range 22.1–39.3 moths), Target lesion failure (TLF) rate was 10.1%. Stent thrombosis and Cardiovascular mortality were observed in 1.2% and 3.6% in of cases, respectively. NOAF occurred in 23 out of 502 patients (4.6%). Patients with NOAF resulted more frequently female, older, obese, diabetic and more frequently experienced TLF and cardiovascular death. NOAF free survival favoured single versus double stent technique and among double stent techniques NIT compared to the others. Single stent strategy had a lower risk of NOAF compared to double stent technique on multivariate analysis (HR: 1.14, 95% CI: 1.10–1.19, p &lt; 0.001 vs HR: 1.28, 95% CI: 1.23–1.32, p &lt; 0.0001).

Conclusions

NOAF in distal LM bifurcation disease treated with PCI had a low incidence but resulted more frequent after double than after single stenting technique and associated with worse outcomes.

3D electro-anatomical mapping to guide conduction system pacing in complex cardiac anatomies

Background

Conduction System Pacing (CSP) includes both His Bundle Pacing (HBP) and Left Bundle Branch Pacing (LBBP). It guarantees physiological cardiac activation and it is essential to avoid pacing-induced dyssynchrony. Markedly dilated atria, up-grading to CRT, and congenital cardiopathies still represent complex anatomical scenarios in which the available tools could often result inadequate and graved by suboptimal results.

Objective

To evaluate the feasibility and effectiveness of 3D electro-anatomical mapping (EAM) to guide CSP (both HBP and LBBP) in patients with characteristics that allows “a priori” classification as complex anatomical scenario with low probability of success using only fluoroscopic guidance and available tools. Left atrium area &gt;40 cm2; post-PICM up-grading and congenital heart disease were considered signs of anatomical complexity.

Methods and results

The study includes 25 patients (19 males, mean age 76–11 years; mean baseline EF 34.2–12.6%; 17 BBB; 5 post-PICM up-grading), candidates for CSP. 16 and 9 were respectively implanted with PM and ICD (13/12 dual/three-chamber devices). CARTO system was used in 6 ptss and EnsiteTM Precision in 19. EAM involved reconstruction of the right atrium and sub-tricuspid septum with the use of a decapolar catheter. Several “tags” have been placed on the His signals, in order to reconstruct the “His Cloud” and distinguish within it the proximal, medium, and distal area (Fig. 1). The sub-tricuspid septum was always reconstructed so that intra-procedurally operator could easily move from HBP to LBBP based on electrical parameters or paced QRS morphology. The mapping catheter was removed after the mapping phase and replaced with the pacing lead. Both exposed fixed screw 3830 leads and standard stylet-driven leads were used. HBP was achieved in 10 pts and LBBP in 13 pts. Three failures were resolved by CS lead implant. The time spend for His cloud mapping was 18±7 min. The mean threshold was 1.1±0.5 V; sensing 11.6±9.3 mV and impedance 786±339 ohm. Baseline QRS 155±19 ms and paced QRS 119±7 ms. In cases of LBBP we were also able to measure on the EAM map the depth of the catheter within the septum, resulting in 11.5±3.1 mm and the distance of the initial screw site from the His of 26.5±10.3 mm.

Conclusions

The electro-anatomical mapping allows the accurate reconstruction of “His cloud” by properly distinguishing proximal, middle, distal His. The sub-tricuspid zone of the interventricular septum is also reconstructed in high definition, so that intra-procedurally it is possible to easily move from HBP to LBBP and vice-versa based on the electrical parameters and paced QRS morphology. This method appears safe and effective even in complex cardiac anatomies possibly saving time and fluoroscopy use. The tags on the His cloud and sub-tricuspid septum can satisfactorily guide lead placement with high reproducibly.

Funding Acknowledgement

Type of funding sources: None. Figure 1. 3D-EAM used to guide HBP implant

Left bundle branch pacing: 2 year single-centre experience

Background

Left Bundle Branch Pacing (LBBP) ensures a physiologic ventricular activation and shows better electrical parameters compared to His bundle pacing (HBP). A growing body of experience is encouraging a large applicability.

Objective

To analyse feasibility and technical outcomes of LBBP in the daily clinical practice.

Methods

During 2019 and 2020, 132 patients (mean age 79±10 years; 72 males) with standard indication for pacing, received the lead deeply intraseptal aiming to pace the left bundle. The indication for pacing were AV block 72 (55%) pts, SND 14 (11%), AF and slow ventricular rate 21 (16%), ablate&pace in 4 (3%); HF in 10 (7.5%), PICM 6 (4%) pts, lead revision in 5 (3.5%). 75% of pts had ischemic cardiopathy; 82% hypertension, 30% diabetes and 21% severe kidney disease. Baseline QRS was 141±38 ms and 68% of pts had bundle branch block. The basal mean EF 49±15%. 91 (69%) of the pts were in sinus rhythm at implant. Criteria for LBBP were: RBB morphology in V1 together with left ventricular activation time (LVAT)&lt;80 ms in V6. Final lead position was always confirmed with injection of 5 ml of dye contrast in left anterior oblique view.

Results

The lead was successfully implanted in the left bundle in 129 (97,7%) patients. In the remaining 3 patients the cathode only penetrated the septum. In 90 cases LBBP was the first choice, in the remaining 42 patients LBBP was aimed after unsatisfactory HBP (His threshold&gt;2V or paced QRS&gt;140 ms). In 107 cases we utilized the 3830 4Fr lumenless lead; in 25 cases the stylet-driven 6 Fr leads. The LBBP lead was connected to the RV port in the 92 dual-chamber PMs; in the LV port in the 22 three-chamber devices as part of cardiac resynchronization therapy; in the only port in 18 single-chamber PM. Mean fluoroscopy time was 10±6 min including implant of all leads. Electrical parameters were highly favourable (R wave sensing 10,5±5 mV; threshold 0,9±0,2 V@0,5 ms; impedance 829±234 ohm). Paced QRS duration was 114±20 ms (P&lt;0.005). The devices were checked 48 hours after implant and 1 month later. Thereafter were remotely monitored. At the 1-month in clinic interrogation all LB lead showed good performance and QRS morphology and duration like the post implant one (115±21 ms). Mean VP% was 81% and mean AP% 28%. VP ≥90% was detected in 42 (32%) of patients. Chronic AF (AT/AF 100%) in 24 (18%) of patients. In 3 cases the LB lead showed early dislodgement requiring lead revision (1 macroscopic dislodgement and 2 rise in threshold), all of them within 7 days after implant.

Conclusion

The new technique of pacing the left bundle of the conduction system (LBBP), is safe and feasible in the clinical practice. It is applicable in all pacing indications including heart failure and resynchronization. In our experience lead dislodgement were 2,2% (3/132, all in the first week after implant) whereas paced QRS duration was significantly shortened and ejection fraction remained normal.

Funding Acknowledgement

Type of funding sources: None.

Selectra 3D- guided conduction system pacing: single-center experience

Background

Conduction system pacing (CSP)is becoming increasingly popular thanks to the ability to both maintain physiological electrical activation in patients with narrow QRS and restore ventricular synchrony in patients with bundle branch block (BBB). The Selectra3D introducer is a new tool able to support the correct positioning and screwing of the catheter on the bundle of His (HBP) or on the left branch (LBBP). It does exist in 3 different shapes: S, M, L (Fig. 1) based on the radius of main curvature. The internal diameter of 7.3 Fr allows it to support both the 3830 lumen-less catheter historically used for CSP, as well as standard 6Fr stylet-driven leads.

Objective

To evaluate the effectiveness of the Selectra3D introducer for CSP (including both HBP and LBBP), considering the procedural success rate and the lead stability (stability of electrical parameters or need for implant revision) in the medium-term follow-up.

Methods and results

The Selectra3D introducer was used in 56 patients' candidates for CSP (mean age 80±6 years). Pacing indications included A-V block in 21 patients, AF with slow ventricular response in 9 patients; SND in 8 patients and HF and severe ventricular dysfunction in 18 patients (of which 4 were PICM). The mean baseline EF was 40±15%. A PM was implanted in 40 patients and an ICD in 16. A standard stylet-driven lead was used in 48 cases, a fixed exposed screw lead was used in 8 patients. HBP was obtained in 21 cases and LBBP in 30 cases, while in 5 cases (8.9%) neither HBP nor LBBP could be obtained. Implants were performed via a left-sided approach in 55 cases and a right-sided approach in 1 case. The baseline QRS duration was 144±38 ms and the paced QRS duration was 118±21 ms. The electrical parameters were optimal with sensing 8.7±8 mV; impedance 625±276 ohm; threshold 1±0.5 V. During follow-up, 2 lead dislodgement (3.9%) (1 HBP and 1 LBBP) were recorded, both within 7 days after implantation. All the others showed stability of the electrical parameters at a mean follow-up of 8.4±4.2 months.

Conclusions

The new Selectra3D introducer supports effectively and safely the lead implant on conduction system catheters (HBP and LBBP), allowing the implant of both exposed fixed screw leads and standard stylet-driven leads, leading to procedural success&gt;90%. The electrical parameters were optimal at implantation and remained stable during follow-up.

Funding Acknowledgement

Type of funding sources: None. Figure 1

Covid-19 and diet: an evaluation of information available on internet in Italy

Background and aim:

during the Coronavirus disease 2019, Italy experienced deep lockdown with closure of almost all activities, with the exception for food shops and few others. During this quarantine, alteration of dietary habits occurred, due to the changes in food availability and mandatory meal house-consumption. The change in dietary habits could somehow be directed by freely accessible information available on internet. Thus, we evaluated the type and the scientific quality of the information provided to the Italian population by the most visible web sites found on Google, relating diet in Covid-19 time.

Methods:

we systematically performed a reliability and content analysis of Italian language websites using Google as search engine and a combination of diet/nutrition/Covid-19 as search terms.

Results:

88 webpages were included in the study, the great part representing newspaper webpages. Institutional webpages, despite having high scientific quality, did not have high visibility. Generally, all the other webpages reported information of medium-quality scientific level.

Conclusion:

finding appropriate solutions to redirect the population’s attention to more reliable and accessible information is mandatory (www.actabiomedica.it).

The Role of Bioactive Phenolic Compounds on the Impact of Beer on Health

This review reports recent knowledge on the role of ingredients (barley, hop and yeasts), including genetic factors, on the final yield of phenolic compounds in beer, and how these molecules generally affect resulting beer attributes, focusing mainly on new attempts at the enrichment of beer phenols, with fruits or cereals other than barley. An entire section is dedicated to health-related effects, analyzing the degree up to which studies, investigating phenols-related health effects of beer, have appropriately considered the contribution of alcohol (pure or spirits) intake. For such purpose, we searched Scopus.com for any kind of experimental model (in vitro, animal, human observational or intervention) using beer and considering phenols. Overall, data reported so far support the existence of the somehow additive or synergistic effects of phenols and ethanol present in beer. However, findings are inconclusive and thus deserve further animal and human studies.

Occurrence of persistent atrial fibrillation during pacing for sinus node disease: The influence of His bundle pacing versus managed ventricular pacing

INTRODUCTION

In patients with sinus node disease (SND), the dual-chamber pacemaker (PM) is programmed in DDDR mode with an algorithm to avoid unnecessary right ventricular (RV) pacing. This pacing mode may prolong PR interval with consequently atrioventricular (AV) asynchrony which is associated with a higher risk of atrial fibrillation (AF). We evaluate whether preserving AV synchrony by setting a fixed AV delay during physiological RV pacing, that is, His bundle pacing (HBP), could reduce the risk of AF occurrence in comparison with a standard pacing mode with an algorithm to avoid unnecessary RV pacing (DDD-VPA).

METHODS AND RESULTS

We collected retrospective data from 313 consecutive patients who had undergone PM for SND. The first occurrence of persistent AF (>7 consecutive days) as a function of the pacing mode was evaluated. HBP and DDD-VPA were implemented in 82 and 231 patients, respectively. Persistent AF occurred in 128 (40.9%) patients over a median follow-up of 70 months (67-105). The DDD-VPA pacing mode was significantly correlated with the occurrence of persistent AF only when the basal PR was long (>180 ms). The risk of persistent AF was significantly lower in patients on HBP than in those on DDD-VPA, adjusted HR = .57 (95% CI, .36- .89, p=.014). Other independent predictors of persistent AF occurrence were: A history of AF (HR = 3.91; 95% CI, 2.48-6.19, p = .001), age, and long PR interval (HR = 2.98; 95% CI, 2.00-4.43, p=.001).

CONCLUSION

In SND patients and long basal PR interval, the HBP may reduce the risk of persistent AF in comparison with the DDD-VPA.

Electrograms guided his bundle pacing implant: moving from radiology to electrical signals

Background

The standard technique to His Bundle Pacing (HBP) based on a fluoroscopic approach might be challenging and fluoro consuming. The electrical signals could lead to a precise and rapid lead implant, thus reducing the fluoroscopy time (FT) and X-ray dose.

Objective

To evaluate the feasibility, efficacy and safety of the electrogram-guided technique to obtain His Bundle pacing (HBP) with minimal or no fluoroscopy use.

Methods

Between October and December 2018, 41 consecutive patients with indication for pacing underwent HBP with the electrogram-guided approach.

Results

Successful HBP was obtained in 39/41 (95%) pts, which is the study population (mean age 78±10 years). S-HBP and NS-HBP were achieved in 23 (59%) and 16 (41%) pts, respectively. Final HBP lead position was achieved in 31/39 (79.4%) pts with zero fluoroscopy, only guided by the electrical signals. In the remaining 8 pts a minimal dose of fluoro (mean 8 sec) has been required to locate the His. Fluoroscopy has been routinely used to remove the sheath and to ensure the slack. The atrial lead has been implanted in a standard fashion. No difference was observed in the FT for HBP lead placement in patients with S-HBP and NS-HBP (mean 8.1±25 sec vs 7.5±20 sec, p=0.8; median value 0 sec vs 0 sec). Moreover, no significant differences were observed in the FT needed for the entire procedure, total Dose Area Product (DAP) and total procedural time among both S-HBP and NS-HBP. The His lead dislodgement occurred in 1 (2.6%) patient one day after the procedure.

Conclusion

HBP could be performed safely and efficiently using the electrograms, with minimal or no fluoroscopy. Fluoroscopy was required during sheath removal and atrial lead placement.

Funding Acknowledgement

Type of funding source: None

The challenge of education in conduction system pacing: results from single or dual operators

Background

The his bundle pacing (HBP) and Left bundle branch pacing (LBBp) techniques are quickly increasing in the cardiovascular interest being the most physiological mode of pacing. Education in these new conduction system pacing (CSP) is mandatory in the modern EP programs. Achieving acceptable implant success rate, together with electrical parameters adequacy is required.

Objective

The aim of the study was to compare clinical and technical outcomes in 2 groups of patients, those implanted by a single operator with large expertise in CSP and those implanted by two operators (one of them during his learning curve).

Methods

Data from 255 consecutive patients (mean age 78±9 years; 186 males) who underwent successful HBP or LBBp implants were collected and analyzed. The operators were classified as expert after performing more than 50 procedures. Baseline caracteristics were not significantly different between the two groups.

Results

After a mean follow-up of 20±10months, we found that there were no differences between patients implanted by 1 single expert operator and 2 operators (1 beginner during his learning cirve supervised by 1 expert operator) in terms of clinical end point (composite of death or heart failure hospitalizations) and technical end point (need for surgical revision of the implant for reason other than battery replacement). Fluoroscopy time (16±17 min vs 9.8±11 min; p 0.004) and procedural time (113±48 min vs 16±17 min; p 0.003) were significantly prolonged when the implant was performed by 2 operators.

Conclusions

Skill acquisition in physiological pacing (both HBP and LBBp) is a nowadays process which cannot put patient's safety at risk. Our experience shows that clinical and technical outcomes were equivalent when the implant was performed by an expert operator or a beginner operator supervised by 1 expert operator. Fluoroscopy time and duration of the procedure were significantly prolonged by the presence of a trainees.

Kaplan Meyer curves

Funding Acknowledgement

Type of funding source: None

The back-up lead in his bundle pacing: evolution over the years

Background

His bundle pacing (HBP) can be affected by high thresholds and low sensing. Thus, in selected patients including a back-up lead is advisable.

Objective

Single-centre retrospective analysis of a large HBP experience, focusing on the back-up lead utilization over the years.

Methods

677 pts (76±8 years; 433 males) were implanted with HBP from 2004 to 2019 July. The pts received S-HBP (67%) or NS-HBP by the 3830 lead. The pacing indications were AV block 54%, sinus node disease 17%, slow atrial fibrillation 23%, heart failure 6%. Ischemic cardiopathy was found in 26%; hypertension in 83%, diabetes in28% pts. Baseline QRS duration was 123±32 ms and EF 56±12%.

Results

266 (39%) pts received the back-up lead. In sinus rhythm we implanted 3-chamber PM (His lead:LV port; VV delay 80 ms: His pulses and apical pacing during the refractory period). 30 pts (11%) received a particular type of 3-chamber PM which provides back-up pacing only if His capture fails, thus saving energy. In atrial fibrillation 2-chamber PM was implanted (His lead: atrial port, DVI). We recorded a significant decrease of back-up lead use over the years, strictly related to operators/centre experience (&gt;70% during the first years, nearly 10% during the last year). The C315 fixed curve sheath, strongly contributed to the rapid reduction of back-up lead use thanks to better lead fixation and stability.

Conclusion

The back-up lead utilization is progressively decreasing. It is strictly related to the operator/centre experience. The presence of the back-up lead could strengthen the Hisian pacing reliability, potentially impacting pacing indication even in advanced conduction disturbances and saving device longevity.

Funding Acknowledgement

Type of funding source: None

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.

P6547The energy cost of His bundle pacing can be curtailed

Introduction

His bundle pacing (HBP) allows physiological ventricular activation and prevents the electrical and mechanical desynchronization generally induced by myocardial stimulation, which can increase the risk of atrial fibrillation and heart failure. On the other hand, reliable HBP capture often requires higher energy than conventional myocardial pacing. This reduces the expected life of the stimulator and might limit the diffusion of HBP in the clinical practice.

Purpose

Decreasing HBP current drain by careful management of stimulation safety margin and pulse duration.

Methods

In 28 patients undergoing DDD pacing with HBP, a third lead was implanted in RV apex to provide back-up pacing on demand. HBP and apical leads were connected, respectively, to the V1 and V2 channels of a 3-chamber stimulator. When HBP was effective, apical sensing occurred within the VV delay and prevented V2 stimulation. In contrast, in case of HBP failure, V2 sensing was missing and apical back-up pacing was promptly delivered at the end of the VV delay. The availability of a back-up pulse on demand allowed reducing the HBP safety margin with no risk. Furthermore, the individual HBP strength-duration curve was derived in the aim of optimizing the Hisian pulse parameters, which are the major determinants of the device current drain.

Results

Correct back-up inhibition by successful HBP and stimulation in the event of capture loss was achieved in all the patients. The latency from Hisian pacing to apical sensing averaged 96±14 ms. According to the pacemaker counters, no back-up pulse was delivered in daily life in 59% of patients. In the remaining, the prevalence of back-up stimulation never exceeded 15% of paced ventricular cycles. The high HBP threshold was essentially due to an increased rheobase (1.2±0.6 V), while the chronaxie ranged from 0.30 to 0.53 ms in 71% of patients (median 0.44 ms), exceeding 0.6 ms only in 29% of the cases. An average current saving of 5.4±3.0 μA was obtained at the expense of a mild reduction in HBP safety margin (from 1.6±0.2 to 1.4±0.1 times).

HBP and apical back-up

Conclusions

Back-up stimulation on demand is a reliable option to decrease HBP current drain and prolong the stimulator service life with full safety. In most of the cases, significant saving can be achieved by pulse shortening, as the chronaxie time is in the same range as with myocardial stimulation and longer pulses are not required. A pulse duration exceeding 0.6 ms is indicated in less than 1/3 of the implants.

Time Trends in Survival of Children with Acute Lymphocytic Leukemia in Piedmont, Italy: A Report from the Population-Based Cancer Registry

Aims and Background

The Childhood Cancer Registry of Piedmont (RTI) periodically updates the life status of each registered child. Given its size, the RTI is the major (albeit geographically limited) Italian source of population-based survival rates of cancer in children. The present report describes time trends in survival of children with acute lymphocytic leukemia (ALL).

Methods

During 1970-87, 429 residents in Piedmont aged 0-14 were diagnosed as having ALL: they have been followed up until 1991.

Results

Five-year survival rates increased from 21% to 72% for children diagnosed ALL respectively in 1970-72 and 1985-87. Major improvements occurred up to the mid-seventies and again between cases diagnosed in the early and late eighties. Improvement in survival was statistically significant for children belonging to classes comprised between 2 and 10 years of age at diagnosis. Period of diagnosis was unrelated to probability of survival among the 13 cases diagnosed ALL at age 0. Survival was unrelated to sex, even in the early seventies and even after consideration of children dying more than 5 years after diagnosis. Between 1976-81 and 1982-87, an improvement in survival was found in all categories of WBC count at diagnosis: the ratio between the two estimates was somewhat higher for children with more than 50,000 WBC/mm3 at diagnosis than for other children.

Conclusions

Present data are compared with those resulting from other population-based series: this exercise can be useful for an overall evaluation of delivery of cancer therapy at the population basis.