DDD Pacemaker Research Articles

Long-term time-course of atrial sensing and incidence of atrial fibrillation in patients with VDD versus DDD pacemakers

Abstract Introduction VDD pacemakers (PM) theoretically have the same advantages with respect to maintaining atrioventricular (AV) synchrony as dual-chamber (DDD) pacemakers, with lower costs and simpler implantation procedure. However, their use is often limited by concerns about the maintenance of atrial sensing (AS) and the occurrence of atrial fibrillation (AF). Purpose We aimed to compare long-term atrial sensing stability, the incidence of AF and complications in VDD and DDD systems. Methods We retrospectively enrolled patients who underwent VDD or DDD PM implantation for AV block between 2014 and 2021 from 2 centers. Clinical, analytical and electrical variables at implantation, their evolution and events at follow-up (25.2±16.2 months) were collected, comparing the groups by Kaplan-Meier and Cox multivariate analysis. Results 487 patients who underwent PM implantation were included, 189 (38,8%) received a VDD PM and 298 (61,2%) a DDD PM. Patients with VDD were older and had a higher prevalence of risk factors and lower atrial voltage at implantation (Table). Complications at implantation and early complications were scarce and without significant differences in both groups. During follow-up, there was a reduction in atrial voltage in the VDD group (implant 1.4+0.8 mV; follow-up 1.2+0.9 mV; p<0.01), with stability in the DDD group (3.8+2.1 vs 3.9+2.2 mV). Total percentages of AS loss were 23.2% (VDD) vs 2.3% (DDD); p<0.01) (Figure 1). In the Cox multivariate analysis the risk of late AS loss was higher in the VDD group (HR=7.6; 95% CI 2.86-20.3; p<0.001) together with the AS values at implant (HR=0.72; 95% CI 0.52-1.00; p=0.052). AS loss was corrected with reprogramming in 23 patients, reintervention was needed in 1 (2%) and VVI was abandoned in 27 (53%). The risk of AF occurrence was lower in the VDD group (HR=0.39 CI 95% 0.18-0.87; p=0.021) (Figure 2). Conclusions In the long term, AS is significantly reduced in VDD MPs, leading to its loss in a quarter of VDD patients. It is usually correctable with reprogramming, rarely requiring abandonment to VVI. AS at implantation is crucial as it is directed related to the AS during follow-up. DDD PMs were independently associated with a higher incidence of AF, with no differences in the remaining complications.TableFigure

Safety and feasibility of left bundle branch pacing for pediatric and congenital heart disease patients

Abstract Background Conduction system pacing (CSP) has evolved and validated in adults. Due to technical challenges, pediatric and congenital heart disease (CHD) patients were excluded from original trials in this field. We report the safety and feasibility results of our initial experience with pediatric and CHD patients undergoing LBBAP (Left bundle branch area pacing). Purpose To analyze the indications, intraoperative outcomes, electrocardiographic and clinical data from the initial follow-up of pediatric and CHD patients who underwent LBBAP. Methods Indications, intraoperative technical issues, electronic parameters of the implant and early complications of consecutive pediatric and CAD patients submitted to stimulation of the conduction system were evaluated. Results This study was performed between February 2022 and November 2023 and recruited 11 consecutive patients with complete AV block (age: 15-43 years; 7 women) who underwent LBBAP. Four patients had congenital heart disease repaired surgically and two patients with congenitally corrected transposition of the great arteries. Upgrading from VVIR to LBBAP underwent in four patients. Right ventricle (RV) leads were extracted in three patients before CSP. DDD pacemakers with Lumneless 3830 pacing leads were implanted in all patients. The pre-implant QRS duration was 146 (104- 200) ms and 120 (110-130) ms after the procedure. The mean left ventricle activation time was 72 (50-90) ms. The R-wave amplitude was 10.00 (6-29) mV, with a stimulation threshold of 0.8 (0.4-1) V x 0.4 ms and impedance of 676 (534-780) ohms. Transition from non-selective to either myocardial or selective capture and fixation beats were respectively demonstrated in five and three patients. The procedure duration was 125 (70-130) min, and the fluoroscopy time was 15.2 (4-23.6) min. LBBAP substantially shortened the QRS duration and improved LV dyssynchrony echocardiographic parameters in four patients with prior epicardial or endocardial pacing. The LBBAP was successful in all patients with no early complications occured. At mean three months follow-up, QRS duration showed no significant changes compared with baseline. Conclusion Our initial experience on cardiac stimulation of the His-Purkinje conduction system through the stimulation of the left bundle branch is a safe and feasible technique in pediatric and CHD patients. The widespread use of this pacing technique is very useful and cost-effective to prevent heart failure in this vulnerable population.

His bundle pacing implantation in octogenarian patients: a substudy of the PACE-CONDUCT trial

Abstract Background His bundle pacing (HBP) is gaining recognition as a valuable alternative for the management of various cardiac conduction disorders. This substudy, conducted within the framework of the PACE-CONDUCT trial, investigates the outcomes of HBP implantation in patients aged 80 years and older, comparing them with a younger cohort. Methods We examined a total of 61 consecutive patients who underwent HBP implantation, utilizing DDD pacemakers, CRT-P, or CRT-D devices, during the years 2021 to 2023. Patients were categorized into two subgroups: those aged younger than 80 years and those aged 80 years or older. The mean age of the entire cohort was 73 years, spanning from 51 to 86 years, with 15 patients (comprising 24.6% of the total) falling into the octogenarian category. His bundle threshold was assessed on the day of implantation, one day post-implantation, and four weeks post-implantation. All HBP implantations were deemed successful, incorporating both selective and non-selective His bundle pacing. Complications were classified as major (necessitating lead or pocket revision) or minor (requiring no revision). Threshold values were converted to volts per milliseconds (volts x milliseconds) for statistical analysis, conducted with IBM SPSS Statistics 29.0. Results Initial analysis revealed a consistent success rate of HBP implantation across all patients, with no discernible differences between the two age groups. Threshold measurements at the day of implantation and after one day indicated no differences between the younger and the older group. However, at the four-week mark, a statistically significant lower threshold of His bundle pacing was observed in the octogenarian group (one-sided p-value 0.028), suggesting a faster stabilization to the chronic threshold of the active fixation His Bundle lead. The comparison of major and minor complications between the age groups, conducted using chi-square tests, revealed no age-related discrepancies. Conclusions This substudy of the PACE-CONDUCT trial underscores the feasibility and safety of His bundle pacing implantation in octogenarian patients, comparable to their younger counterparts. While no initial threshold variations are observed, the octogenarian group demonstrated improved His bundle pacing thresholds approximately four weeks post-implantation. Importantly, the study revealed no heightened complication risk associated with advanced age, affirming that very old patients aged 80 or older can derive the benefits of His bundle pacing without increased complication rates. Given the relatively modest patient cohort in this study, further investigations are warranted to validate and extend these findings.T-tests and Chi square tests

Permanent Pacemaker Implantation in a Patient with Congenitally Corrected Transposition of Great Arteries and Mesocardia: An Infrequent Happenstance

We present a compelling case of a 37-year-old male who, after three decades of asymptomatic living, was diagnosed with congenitally corrected transposition of great arteries (CCTGA). Initially presenting with troubling symptoms of dizziness and syncope, further evaluation revealed complete heart block, a significant finding necessitating intervention. Despite the rarity of symptomatic presentation in CCTGA, the severity of the heart block prompted the implantation of a DDD pacemaker to ensure adequate management. With meticulous care and precision, the implantation procedure was successfully executed, offering hope for improved cardiac function and symptom relief. Remarkably, the patient remained asymptomatic during subsequent follow-up visits, highlighting the effectiveness of the intervention in mitigating the risks associated with high atrioventricular block in CCTGA. This case serves as a testament to the importance of vigilant monitoring and timely intervention in managing complex cardiac anomalies, ultimately enhancing patient outcomes and quality of life.

Single-Chamber and Dual-Chamber Pacemaker Devices in Adults with Moderate and Complex Congenital Heart Disease: A Single Tertiary Referral Center Experience.

The number of device implantation procedures has increased in adult patients with congenital heart disease (ACHD). Despite significant improvements in materials and implantation techniques, these patients are exposed to higher risk of device related complications than general population. Herein, we describe our single tertiary referral center experience on transvenous pacemaker (PM) implantation and follow-up in adult patients with moderate and complex congenital heart disease (CHD) as limited data are available on long-term outcome. We considered all adults with moderate and complex CHD aged more than 16 years who underwent transvenous single-chamber and dual-chamber PM implant for sinus node dysfunction or atrioventricular block between January 2013 to December 2022 at our Unit. Seventy-one ACHD patients were included in the study (mean age 38.6 ± 15.2 years, 64% with moderate CHD, 36% with complex CHD). Among 32 patients implanted with a dual chamber PM (DDD PM), 4 devices were reprogrammed in VDD mode, 3 in VVI and 2 in AAI mode during follow-up because of lead dysfunction or permanent atrial arrhythmia. In addition, 26 patients had a single chamber PM (AAI or VVI PM) and 13 patients had single-lead pacing system with a free-floating atrial electrode pair (VDD PM). Just one of 13 single-lead VDD PM was reprogrammed in VVI mode due to a low atrial sensing. In DDD PM group, 10 re-interventions were needed due to lead dysfunction (8 cases) and lead-related infective endocarditis (2 cases). Only 3 patients in the single-lead PM group developed lead dysfunction with 2 re-interventions needed, but no infective endocarditis was reported. The rate of long-term complications is high in moderate and complex ACHD with transvenous PM devices, and it is mainly lead-related. In our experience, the less leads implanted, the less complications will occur. Considering the heterogeneity of the ACHD population, transvenous single-chamber or dual-chamber PM device implantation should always be tailored on the single patient, balancing risks and benefits in this complex population.

Lead Extraction in Children and Young Adults: When is the Best Time for Lead/System Replacement?

The best strategy for lead management in children is a matter of debate, and our experiences are limited. This is a retrospective single-center study comparing difficulties and outcomes of transvenous lead extraction (TLE) implanted ich childhood and at age < 19years (childhood-implanted-childhood-extracted, CICE) and at age < 19 (childhood-implanted-adulthood-extracted, CIAE). CICE patients-71 children (mean age 15.1years) as compared to CIAE patients (114 adults (mean age 28.61years) were more likely to have VVI than DDD pacemakers. Differences in implant duration (7.96 vs 14.08years) appeared to be most important, but procedure complexity and outcomes also differed between the groups. Young adults with cardiac implantable electronic device implanted in childhood had more risk factors for major complications and underwent more complex procedures compared to children. Implant duration was significantly longer in CIAE patients than in children, being the most important factor that had an impact on patient safety and procedure complexity. CIAE patients were more likely to have prolonged operative duration and more complex procedures due to technical problems, and they were 2-3 times more likely to require second-line or advanced tools compared to children, but the rates of clinical and procedural success were comparable in both groups. The difference between the incidence of major complications between CICE and CIAE patients is very clear (MC 2.9 vs 7.0%, hemopericardium 1.4 vs 5.3% etc.), although statistically insignificant. Delay of lead extraction to adulthood seems to be a riskier option than planned TLE in children before growing up.

Safety of epinephrine-containing local anaesthesia in CIED implantations

Abstract Funding Acknowledgements Type of funding sources: None. Background Cardiac implantable electronic devices (CIED) are common. Permanent pacemaker implantations can improve quality of life of patients with sick-sinus syndrome and prolong survival in those with infranodal high-grade AV block. Nonetheless, pocket haemathoma can be problematic post CIED implantation, especially with the increasing use of oral anticoagulants and antiplatelet agents (especially P2Y12 inhibitors) in the at-risk population. The use of epinephrine in local anaesthetic is common in UK but remains controvesial with 2021 EHRA consensus statement recommending its avoidance(1). Aim To compare the rate of pocket haemathoma and subsequent haemathoma drainage and pocket revisions in CIED patients who have received epinephrine-containing local anaesthetia versus local anesthesia without epinephrine. Methods Retrospective, observational studies across a disctrict general hospital and tertiary cardiology hospital, involving a total of 377 consecutive CIED patients over the course of 2021 - 2022. Patients' demographics, comorbidities, peri-procedural medication use and complication events were retrived from electronic data base. Types of local anaesthesia were recorded. Results and Outcomes Out of 377 patients, 184 patients received 1% epinephrine-containing local anaesthesia (Group 1) and 193 patients received plain local anesthesia only (Group 2). In terms of baseline demographics (age and gender distribution), associated comorbidities (treated hypertension, diabetes type 2, ischaemic heart disease, hypercholesterolemia, smoker) were not statistically different between both groups. Number of leads implanted (DDD vs VVI vs ILR) were not statistically different (26.6% DDD pacemaker and 65.8% VVI pacemaker in Group 1 versus 34.8% DDD and 57.0% VVI in Group 2, p=0.143). Periprocedural usage of oral anticoagulations (38.6% vs 30.5%,p=0.102) and single or dual antiplatelet agents (31.5% vs 29.0%, p=0.796) were not different between both groups. Overall complication rates were low and not statistically different between both groups: 4.35% in Group 1 versus 6.74% in Group2. Only 1 patient received epinephine-containing local anesthesia experienced pocket haemathoma against 6 patients who received plain local anaesthsia (0.543% vs 3.11%,p=0.122). No patients require evacuation of haemathoma, drainage or subsequent pocket revision (p= 1.0). Summary: The results of this retrospective observational study demonstrated that 1% epinephrine-containing local anesthesia for CIED implantation is not associated with increased risk of pocket haemathoma, no increased risk of haemathoma evacuation, drainage or pocket revision. This is despite peri-procedural anticoagulation or antiplatelet use exceeding 70%. This "real-life" result is incongruent with the published MAITRE study which formed the basis for the 2021 EHRA expert consensus statement. Recommendation surrounding epinephrine-containing local anaesthesia in CIED implantation may need to be reviewed.

Reducing radiation exposure and incision time in pacemakers implantation procedures using direct percutaneous axillary vein puncture

Abstract Funding Acknowledgements Type of funding sources: None. Introduction Radiation exposure during device implantation depends overall on the operator experience but also on the type of venous access, type of device and number of leads implanted. Purpose to investigate radiation exposure/incision time for uni/bicameral pacemakers (PM) implantation procedures using direct percutaneous axillary vein puncture without primary fluoroscopy guidance and to assess the safety and the efficiency of this procedure strategy. Methods single center retrospective cohort study of patients implanted with unicameral and bicameral PM between January 2020 and December 2020 using direct percutaneous axillary vein puncture. All pts were given detailed explanations and informed consent. Procedural steps were: (I) direct percutaneous axillary vein puncture (anatomical landmarks: 1 or 2 cm medial and parallel to the deltopectoral groove at the level of the coracoid process); obtain separate vein access: 1 or 2 punctures; (II) skin incision and subcutaneous pocket dissection; (III) right ventricle (RV) ± right atrium (RA) lead placement and fixation. We analyzed the following data: fluoroscopy/incision time, dose area product (DAP) and the outcome related to procedure difficulties and complications. Results We collected data from 209 consecutive implant procedures; 152 patients (pts) underwent bicameral PM implantation, 57 pts received a unicameral device. All the procedures were done by the same operator (54 yo, 22 years of experience in PM implantation) using axillary access alone (2 years' experience in this technique). In 37 patients (18%) fluoroscopy guided puncture was needed. The mean fluoroscopy time was: bicameral PM 1.2±1.0 min (average incision time: 8.4±5.2 min); unicameral PM 0.4±0.3 min (average incision time: 6.5±4.3 min). The mean DAP was: bicameral PM 0.00358±0.00545 mGy/cm2; unicameral PM 0.00285±0.00449 mGy/cm2. In short term follow-up 1 patient (0.4%) developed pneumothorax and subsequent drainage was needed. Total follow-up period 19.7±4.3 months: at 6 months follow-up 1 patient (0.4%) presented lead fracture; 1 patient with DDD PM (0.4%) presented pocket infection; leads extraction were successful performed and another device was implanted. No other complications were noted. Conclusion Single venous access using axillary vein puncture was associated with reduced radiation exposure and decreased incision time. Our data showed a low incidence of complications.

P231 CORONARY VASOSPASM REFRACTORY TO MEDICAL THERAPY AND COMPLICATED BY ASYSTOLE, HOW TO MANAGE IT?

Abstract Vasospastic angina is a form of angina caused by coronary artery spasm. This usually determines rest chest pain and electrocardiogram changes. In some patients severe ventricular tachyarrhythmias or bradyarrhythmias may develop during myocardial ischemia. Vasospastic angina attacks can be prevented by calcium antagonists and nitrates but artery spasm may be refractory to optimal medical therapy. A 66–year–old woman, affected by Hailey–Hailey disease was brought to the emergency department for hemorrhagic shock after anti–conservative purposes. She underwent emergency surgery for haemostasis of the neck lesion, reinsertion of the subhyoid muscles and right parotidectomy. After surgery an electrocardiogram (ECG) showed inferior and posterior ST–segment elevation, total atrioventricular block (AVB) and torsades de pointes (FIG 1), then evolved in asystole and cardiac arrest . ROSC occurred in 4 minutes. Temporary pacemaker (PM) was placed. Coronary angiography showed right coronary artery and left anteriori descending artery vasospasm, slightly reduced after nitroglycein infusion (FIG 2). Transdermal nitrates and calcium channel blocker were started. Hospitalization has been prolonged due to infectious/psychiatric problems, with necessity of percutaneous endoscopic gastrostomy and tracheostomy, A new episode of vasospastic angina developed during hospitalization with recurrence of total AVB and torsades de pointes. Temporary PM was placed but after 24 hours perforated the right ventricle free wall. Echocardiogram showed small circumferential pericardial effusion. The patient underwent transvenous removal of the right ventricular catheter and two lead DDD PM was implanted. She was discharged with nitrate and calcium channel blocker therapy. No recurrence of angina was documented at 6–months follow–up. The management of this clinical case was complex because it was a form of vasospastic angina complicated by 2 cardiac arrests, unresponsive to medical therapy and with temporary PM that perforated the right ventricle. We therefore opted for a definitive PM implant for protection. Few case report describes definitive PM implantation in fatal bradyarrhythmias during vasospastic angina. To date, the best treatment of coronary vasospasm refractory to medical therapy is debated, pecutaneous revascularization and sympathectomy are considered, treatment methods that we will consider at follow–up in case of (probable) anginal recurrences.

434 TAKOTSUBO SYNDROME AFTER PACEMAKER IMPLANTATION

Abstract Introduction Takotsubo syndrome is a clinical syndrome characterized by typical anamnestic features together with typical ECG and echocardiographic findings. Comparing with the available literature not so many cases of takotsubo syndrome after pacemaker implantation can be found. Furthermore, there are only few articles talking about ECG features in these patient. The case we described allows to observe dynamic ECG alterations in a patient with electro-induced ventriculograms Case Description A 90-year-old male was admitted to the emergency room for important fatigue associated with severe bradycardia (25/min). His cardiovascular history was silent, and his past medical history was characterized by high blood pressure, chronic pulmonary obstructive disease and anemia due to iron deficiency. The ECG showed second degree AVB type 2, with phases of 2:1 AVB and paroxysmal third degree AVB on continuous monitoring. The routine blood tests showed normal T troponin and BNP was 420 pg/mL. The echocardiogram revealed normal biventricular dimensions and systolic function with moderate aortic valve stenosis. The patient underwent urgent permanent DDD pacemaker implantation without previous isoproterenol administration. During the procedure he referred important pain on the site of the wound, and he became confused and agitated. The procedure was complicated by massive pneumothorax that needed quick decompression. On the 2nd day after pacemaker implantation the ECG revealed electro-induced atrium-guided ventriculograms and began to modify with only mild ST-segment elevation in V2 and initial T-wave inversion from V3 to V6 and in I - II - aVF. On the next days, T-waves became deeper and QTc prolonged to 540 ms. These abnormalities were then gradually resolved on the 11th day. Mild transient attenuation of the amplitude of the QRS complexes in V2 – V3 leads on day 1 could be reported. Another echocardiogram was then performed, which showed new apical akinesis with “apical ballooning” aspect and EF of 40%. TnT and BNP values increased. Coronary angiogram was not performed due to patient rejection, so that coronaropathy could not be excluded with certainty. Nevertheless, the patient had only high blood pressure as cardiovascular risk factor and that the probability of the diagnosis of takotsubo cardiomyopathy was assessed of 76,9% by InterTAK diagnostic score, so that we considered Takotsubo syndrome the most likely diagnosis. Therefore, the patient's therapy was then optimized with an increase in the dosage of ACE inhibitors. At one month follow-up the ECG remained stable, and the echocardiogram showed a preserved ejection fraction (EF = 55%), without alterations of the segmental contractility. BNP and TnT values were normal. Therapy was left unmodified. Conclusions Takotsubo syndrome should be consider a rare but possible complication of pacemaker implantation. This is true especially for patients affected by frailty and cognitive impairment. There are no specific ECG criteria for takotsubo syndrome in patients with electro-induced ventriculograms, but anomalies of the repolarization are similar to those in patients with spontaneous ventricular activity. Transient attenuation of the QRS complexes voltages could be seen even just in the precordial leads and it is generally present in the very acute phase.

Can we explore AF–pacemakers’ relationship using clinical and echocardiographic parameters in patients with permanent pacemaker? (Echocardiography and subclinical AF in permanent pacemaker)

Patients on implanted permanent pacemakers frequently develop atrial fibrillation (AF). We aimed to determine the Echocardiographic and clinical parameters predicting AF in patients with a dual-chamber (DDD) pacemaker. This retrospective study included 208 patients with permanent pacemaker, classified according to development of AF during follow up into 2 groups: AF (77, 37%) and non AF (131, 63%), baseline: clinical, ECG(P-wave dispersion) and echo {diastolic wall strain (DWS),left arial volume index (LAVI), left ventricular stiffness index(LVSI)} data were assessed. AF group were older with more P wave dispersion, lesser DWS, greater LVSI& LAVI, LVSI at a cut off > 0.13 and DWS at a cut off < 0.34 were predictors of AF in patients with DDD pacemakers. LVSI and DWS could be used as simple good predictors for AF in patients with DDD pacemakers, for timely initiation of anticoagulants according to CHA2DS2VASc score to decrease ischemic stroke burden.

Powikłania po wszczepieniu stymulatora serca u 81-letniej pacjentki

This case report presents the medical history of an 81-year-old woman with heart failure with preserved ejection fraction, sinus node disease in the form of symptomatic bradycardia, persistent atrial fibrillation, acute tricuspid regurgitation surgically repaired in 2013, and moderate mitral regurgitation. The patient had a pacemaker implanted in 1995 which was removed in 2013 due to a pacemaker pocket infection. The procedure was complicated by tricuspid valve injury. The patient underwent valve reconstruction and an epicardial DDD pacemaker implantation. The pacemaker generator was located in a space developed between the muscles and fascia of the abdominal wall. Currently, due to increasing ventricular exit block and pacemaker battery depletion, the decision was made to implant a leadless MICRA pacemaker.

Intermittent positional axillary vein compression – a rare complication of CIED implantation

An 81-year-old male with an implanted DDD pacemaker reported fluctuating edema accompanied by pain and paresthesia affecting the hand and arm on the side the pacemaker had been implanted. These symptoms, which developed several weeks after the procedure, were more pronounced in the morning and resolved during the day. Venography showed axillary vein compression, whose severity varied with different arm positions. Changing the location of the pacemaker pocket restored normal venous blood flow at the site of compression and relieved the patient’s symptoms, which was confirmed during follow-up.

Benefits for clinical outcomes associated with dual-chamber pacing versus ventricular pacing in patients with sinus-node dysfunction: a nationwide matched control study

Abstract Introduction Evidence from randomized trials suggests that, in patients with sinus-node dysfunction (SND), physiologic pacing (dual-chamber, DDD) may be superior to single-chamber (ventricular, VVI) pacing because it is associated with lower risks of atrial fibrillation and stroke, better exercise capacity and lower risk of pacemaker syndrome. However, benefits on mortality and risk of heart failure have not been demonstrated and these issues have not been fully evaluated in large “real life” analyses. The aim of our study was to assess and compare clinical outcomes within the first 30 days and during a longer-term follow-up with the two types of pacing at a nationwide level for patients with SND. Methods Using the administrative hospital database in France 2010–2020, 52,974 patients with SND were included in the analysis: 4,069 patients had VVI pacing and 48,905 had DDD pacing. Patients with leadless VVI pacemakers were excluded of the analysis. After propensity score matching 2,213 patients with VVI pacemaker were matched 1:1 with 2,213 patients treated with DDD pacemaker. Results In the matched analysis, patients with DDD pacemakers had a lower rate of all-cause (hazard ratio HR 0.711, 95% CI 0.61–0.828) and cardiovascular death (HR 0.628, 95% CI 0.48–0.818) within the 30 days after implantation. There were no significant differences for incidence of tamponade (HR 0.666, 95% CI 0.11–3.992), pneumothorax (HR 1.000, 95% CI 0.32–3.105), hemothorax (HR 0.800, 95% CI 0.21–2.982), major bleeding (HR 0.824, 95% CI 0.68–1.005) and transfusion (HR 1.016, 95% CI 0.83–1.243). During subsequent follow-up (mean: 3.0±2.8 years), risk of all-cause death in the matched population was significantly lower in the DDD group than in the VVI pacemaker group (HR 0.683, 95% CI 0.60–0.784). Patients with SND treated DDD pacemakers also had a lower risk of cardiovascular death (HR 0.569, 95% CI 0.44–0.732), new-onset atrial fibrillation (HR 0.638, 95% CI 0.58–0.706), ischemic stroke (HR 0.685, 95% CI 0.53–0.887) and hospitalization for heart failure (HR 0.758, 95% CI 0.68–0.850) than those treated VVI pacemakers, whilst risk of endocarditis was not significantly different (HR 0.986, 95% CI 0.50–1.951). Conclusion Patients with SND treated with DDD pacemakers had better clinical outcomes compared to those treated with VVI pacemakers. DDD pacing was associated with lower risks of death, cardiovascular death, new-onset atrial fibrillation, ischemic stroke, hospitalization for heart failure. DDD pacing was neither associated with a higher risk of complication on the short-term nor of endocarditis on the longer-term. Funding Acknowledgement Type of funding sources: None.

B-PO05-192 DUAL CHAMBER CLOSED LOOP STIMULATION PACING PREVENTS CARDIOINHIBITORY SYNCOPE IN YOUNG PATIENTS

Cardioinhibitory syncope (CIHS) is a subtype of neurocardiogenic syncope (NCS) characterized by abrupt bradycardia/long sinus pauses and syncope with minimal prodrome and is often refractory to standard therapies. The BiotronikTM DDD-CLS (Closed Loop Stimulation) algorithm paces preemptively in response to beat-to-beat surges in cardiac contractility to prevent CIHS syncope. To evaluate the efficacy of DDD-CLS pacing to prevent CIHS syncope in young patients. All patients with CIHS onset before age 18 and treated with DDD-CLS pacemaker at our institution from 2008-2020 were included as well as 2 patients with drug-refractory NCS without long pauses. Retrospective chart review assessed diagnostics and patient reported onset, duration and frequency of syncope. Eleven patients (9 female) received DDD-CLS pacemakers for CIHS (9pts) or drug-refractory NCS with bradycardia (2pts). Long sinus pauses (median 17 sec/range 7-26 sec) were recorded in 9 patients with CIHS. Median age at implant was 16.2 (11-26) years. Onset of syncope was a median of 4.5 (0.3-16.5) years prior to implant and median follow up after implant was 6.9 (0.25-12) years. Patient reported syncope decreased from 7.0/pt-yr to 0.28/pt-yr (p< 0.003 by Wilcoxon Signed-Rank test). Four patients experienced 7 total episodes of syncope after DDD-CLS pacing. Seven pts had no recurrences, including one patient who failed prior DDD pacemaker treatment. DDD-CLS was highly effective at eliminating or reducing CIHS in young patients. Its potential role for patients with typical NCS warrants further evaluation.

Clinical outcomes with ventricular pacing or dual-chamber pacing for sinus-node dysfunction: a nationwide matched control study

Abstract Funding Acknowledgements Type of funding sources: None. Introduction.Evidence from randomized trials suggests that, in patients with sinus-node dysfunction (SND), physiologic pacing (dual-chamber, DDD) may be superior to single-chamber (ventricular, VVI) pacing because it is associated with lower risks of atrial fibrillation and stroke, better exercise capacity and lower risk of pacemaker syndrome. However, benefits on mortality and risk of heart failure have not been demonstrated and these issues have not been fully evaluated in large "real life" analyses. Objective.The aim of our study was to assess and compare clinical outcomes within the first 30 days and during a longer-term follow-up with the two types of pacing at a nationwide level for patients with SND. Methods and results.Using the administrative hospital database in France 2010-2020, 52,974 patients with SND were included in the analysis: 4,069 patients had VVI pacing and 48,905 had DDD pacing. Patients with leadless VVI pacemakers were excluded of the analysis. After propensity score matching 2,213 patients with VVI pacemaker were matched 1:1 with 2,213 patients treated with DDD pacemaker. In the matched analysis, patients with DDD pacemakers had a lower rate of all-cause (hazard ratio HR 0.711, 95%CI 0.61-0.828) and cardiovascular death (HR 0.628, 95%CI 0.48-0.818) within the 30 days after implantation. There were no significant differences for incidence of tamponade (HR 0.666, 95%CI 0.11-3.992), pneumothorax (HR 1.000, 95%CI 0.32-3.105), hemothorax (HR 0.800, 95%CI 0.21-2.982), major bleeding (HR 0.824, 95%CI 0.68-1.005) and transfusion (HR 1.016, 95%CI 0.83-1.243). During subsequent follow-up (mean: 3.0 ± 2.8 years), risk of all-cause death in the matched population was significantly lower in the DDD group than in the VVI pacemaker group (HR 0.683, 95%CI 0.60-0.784). Patients with SND treated DDD pacemakers also had a lower risk of cardiovascular death (HR 0.569, 95%CI 0.44-0.732), new-onset atrial fibrillation (HR 0.638, 95%CI 0.58-0.706), ischemic stroke (HR 0.685, 95%CI 0.53-0.887) and hospitalization for heart failure (HR 0.758, 95%CI 0.68-0.850) than those treated VVI pacemakers, whilst risk of endocarditis was not significantly different (HR 0.986, 95%CI 0.50-1.951). Conclusion.Patients with SND treated with DDD pacemakers had better clinical outcomes compared to those treated with VVI pacemakers. DDD pacing was associated with lower risks of death, cardiovascular death, new-onset atrial fibrillation, ischemic stroke, hospitalization for heart failure. DDD pacing was neither associated with a higher risk of complication on the short-term nor of endocarditis on the longer-term.

Applications designed to successfully implant in challenging left atrial appendage occlusion cases: a new tool for the interventional cardiologist

An 85-year-old patient with permanent atrial fibrillation with a DDD pacemaker, and with indication for left atrial appendage occlusion (LAAO). Sent for LAAO due to recurrent gastrointestinal bleedings even on apixaban and with a CHA 2 DS 2 VASc and HAS-BLED scores of 4 and 3 respectively.

Effect of Dual-Chamber Pacemakers with Various Atrioventricular Intervals on Systolic Function, Diastolic Function, and Plasma Level of NT-pro BNP in a Sample of Iraqi Patients

Background: The use of dual-chambers (DDD) pacemakers is steadily increasing a year after year and oneof the programmable settings for these pacemakers is the duration of the atrioventricular interval (AVI).AVI manipulation is justified for a variety of reasons including better hemodynamic stability and extendingthe battery life of the pacemaker. Since plasma NT-proBNP level reflects the myocardial wall tension, wehypothesized that different durations of AVI may have an effect on cardiomoycytes stretch and myocardialwall tension and hence an effect on plasma NT-proBNP level. So we tried to use plasma NT-proBNP as amarker for that strain, if present. Also, we tried to explore the effect of DDD pacemakers on both the systolicand the diastolic functions of the heart using conventional echocardiographic parameters.Methods: 52 patients with permanent dual-chambers pacemaker were recruited. We exclude those withheart failure, renal impairment, and major valvular or coronary vessels disease. All patients had a thoroughmedical history and examination, ECG, echocardiography (2-D, M-mode, and Doppler) as well as bloodsampling for NT-proBNP. Based on the shape of their E-A waves by pulsed-wave Doppler of transmitralflow, they were grouped in 3 categories. Group-A included those with truncated A-wave, group-B comprisedthose with separated E and A waves, and group-C involved those with fused E-A waves with or withoutdiastolic mitral regurgitation.Results: there was statistically significant difference in the duration of AVI among the 3 groups (p &lt;0.001)with patients having fused E-A waves recorded the longest AVIs. Plasma NT-proBNP levels were significantlyhigher when E-A waves were fused (p &lt;0.001). The systolic parameters such as the cardiac output, the strokevolume and the ejection fraction were higher when there was neither A-wave truncation nor E-A wavefusion (p &lt;0.001). All patients showed evidences of diastolic dysfunction.Conclusion: despite the fact that DDD pacemakers are more physiological mode of pacing, neverthelessthey induce some grade of diastolic heart failure. Manipulating the AVI into longer than the device`s defaultvalues should be carefully judged since it is associated with higher levels of plasma NT-proBNP levels thatreflect cardiac wall tension and strain which in turn may progresses in future into another cardiac problemssuch as atrial fibrillation.

Implantation of an S-ICD in a Patient with a DDD Pacemaker and Congenitally Corrected Transposition of the Great Arteries

Subcutaneous implantable cardioverter-defibrillator (S-ICD) therapy has become a viable alternative to conventional transvenous ICD implantation. Patients with congenitally corrected transposition of the great arteries (ccTGA) have a high risk of sudden cardiac death due to malignant arrhythmia. The interaction between the S-ICD system and the transvenous pacemaker system is not fully understood. We report a case of S-ICD implantation in a patient with ccTGA and a DDD pacemaker. The patient was a 30-year-old man with a previously placed pacemaker with diagnoses of congenital heart disease, ccTGA (SLL), left atrioventricular valve insufficiency, and third-degree atrioventricular block. He presented with an out-of-hospital cardiac arrest, and an S-ICD was implanted to prevent sudden cardiac death. Defibrillation checks were performed successfully. We tested the compatibility of the DDD pacemaker with the S-ICD and found that there was no interference between them. In conclusion, an S-ICD system is a reasonable and safe option in patients with ccTGA.

Effective extension of the pacemaker to the CRT-P with simultaneous percutaneous recanalization of the obstructed left brachiocephalic vein

We present a case of a man with a previously implanted DDD pacemaker, NYHA functional class III heart failure and asymptomatic left brachiocephalic vein obstruction. The DDD pacemaker was extended to the system of resychronization CRT-P despite obstruction of the left brachiocephalic vein.