PM Implantation Research Articles

Predictors of complications and mortality among patients undergoing pacemaker implantation in resource-limited settings: a 10-year retrospective follow-up study

IntroductionPacemakers (PMs) are used to treat patients with severe bradycardia symptoms. They do, however, pose several complications. Even with these risks, there are only a few studies assessing PM implantation outcomes in resource-limited settings like Ethiopia and other sub-Saharan countries in general. Therefore, this study aims to assess the mid-term outcome of PM implantation in patients who have undergone PM implantation in the Cardiac Center of Ethiopia by identifying the rate and predictors of complications and death.MethodologyThis retrospective study was conducted at the Cardiac Center of Ethiopia from October 2023 to January 2024 on patients who had PM implantation from September 2012 to August 2023 to assess the midterm outcome of the patients. Complication rate and all-cause mortality rate were the outcomes of our study. Multivariable logistic regression was used to identify factors associated with complications and death. To analyze survival times, a Kaplan–Meier analysis was performed.ResultsThis retrospective follow-up study included 182 patients who underwent PM implantation between September 2012 and August 2023 and were at least 18 years old. The patients' median follow-up duration was 72 months (Interquartile range (IQR): 36–96 months). At the end of the study, 26.4% of patients experienced complications. The three most frequent complications were lead dislodgement, which affected 6.6% of patients, PM-induced tachycardia, which affected 5.5% of patients, and early battery depletion, which affected 5.5% of patients. Older age (Adjusted Odds Ratio (AOR) 1.1, 95% CI 1.04–1.1, p value < 0.001), being female (AOR 4.5, 95%CI 2–9.9, p value < 0.001), having dual chamber PM (AOR 2.95, 95%CI 1.14–7.6, p value = 0.006) were predictors of complications. Thirty-one (17%) patients died during the follow-up period. The survival rates of our patients at 3, 5, and 10 years were 94.4%, 92.1%, and 65.5% respectively with a median survival time of 11 years. Patients with a higher Charlson comorbidity index before PM implantation (AOR 1.2, 95% CI 1.1–1.8, p = 0.04), presence of complications (AOR 3.5, 95% CI 1.2–10.6, p < 0.03), and New York Heart Association (NYHA) class III or IV (AOR 3.3, 95% CI 1.05–10.1, p = 0.04) were associated with mortality.ConclusionMany complications were experienced by patients who had PMs implanted, and several factors affected their prognosis. Thus, it is essential to identify predictors of both complications and mortality to prioritize and address the manageable factors associated with both mortality and complications.

Permanent epicardial pacing : a first line strategy in children

Abstract Background Permanent cardiac pacing in paediatric patients remains a challenge. According to the European Paediatric and Congenital Society (AEPC) recommendations, below 20 kg epicardial implantation is preferred, while above 20 kg endocardial implantation is given priority unless specific contraindication. In the literature, a weight at 15 kg is also found to be the minimal weight above which an endovascular implantation is considered. However, endovascular systems have been reported to be associated with a high risk of complications. Recent improvements in epicardial leads technology have significantly improved pacing thresholds (1-3), battery life and reduced the risk of re-intervention for epicardial lead dysfunction (4,5). Purpose The aim of the study is to evaluate the long-term results and efficacy of epicardial pacing in children and to investigate risk factors for epicardial lead dysfunction. Method We performed a retrospective, single-centre analysis of consecutive patients aged ˂18 years implanted with an epicardial PM between 2004 and 2020. The data collection included initial pacing parameters, at 1 month, 1 year, 2 years, and at last follow-up, as well as occurrence of early and late complications. Results A total of 101 patients (93 atrial and 131 ventricular epicardial) were analysed. The mean follow-up time was 6.2 years (range 2 days to 16.9 years). Median age at implantation was 4.2 years (IQ 0.3-8.8 years), median weight was 15.2 kg (IQ 5.2-28.0 kg). Congenital heart disease (CHD) was recorded in 59,4% of patients. Reasons for implantation were postoperative complete atrioventricular block (AVB) (40.6%), congenital AVB (37.6%), sinus dysfunction (7.9%), complete AVB with heart disease without surgery (7.9%), others (4%). Four patients had a system infection resulting in device extraction and reimplantation. The mortality rate was 15.8%, but no deaths was directly related to PM implantation or dysfunction. Detection values, impedances were stable over time, and the and average pacing thresholds remained ˂0,98±0,81 volt in the atrium and ˂ 1.57±0,89 volt in the ventricle. Lead survival was 96,7%, 90,7%, 82,3%, 74,5% at 1, 5, 8 and 10 years. The presence of CHD, weight ˂15kg, dual chamber implantation, implantation for postoperative BAV were not significant risk factors for lead dysfunction. In the group of patients implanted above 15kg the presence of a CHD significantly increased the risk of lead dysfunction (p=0.037) and all-cause reimplantation (p=0.010). In the group implanted above 15kg without any cardiopathy, the survival rate without lead dysfunction at 5 and 10 years was 100% and 90.9% respectively. Conclusion Epicardial pacing in children with steroid-eluting leads shows good long-term results with stable pacing parameters and good survival from lead dysfunction. For children implanted at a weight above 15 kg and without cardiopathy results with epicardial stimulation were excellent.Epicardial lead survival

GUIDEWIRE SHAPE MODIFICATION: A SIMPLE TECHNIQUE TO PREVENT CONDUCTION SYSTEM INJURIES DURING TRANSCATHETER VALVE IMPLANTATION

Abstract Background Atrioventricular (AV) conduction abnormalities remain one of the important unsolved issues with transcatheter aortic valve implantation (TAVI). To minimize trauma on the conduction fibers, we introduced a simple technique involving the bending of the stiff guidewire wire at the level of the arch to prevent and minimize contact with the interventricular septum. Aim To report the technique for shape manipulation of the stiff guidewire during TAVI and to evaluate its safety and effectiveness in reducing the need for permanent pace–make implantation after TAVI. Methods and Results Before insertion into the left ventricle the TAVI stiff wire was bended by hand to obtain a ³180° degree curve 15–20cm from its tip. Distance between stiff wire and septum was assessed in cranial–lao cusp overlap projection. Among 26 consecutive patients who underwent TAVI with a bended stiff wire, 13(50%) presented preoperative factors of increased risk for need of PM implantation after TAVI due to LVOT calcification (10, 38.5%), bicuspid aortic valve with raphe opposite to the septum (2, 7.7%) and baseline RBBB (2, 7.7%). Wire was observed to be distant from the septum &amp;gt;5mm in 22/26 (85%) cases. Median distance from septum was 9.0 [6.0, 12.0] mm. Pre–dilatation was required in 20 patients (77%). Balloon was observed to inflate distant from septum in 18 (90%) of them. Self–expandable valves were most frequently employed (n = 21, 81%).No patient required new PM implantation after TAVI. The two patients with baseline RBBB developed transient complete AVB, which recovered before discharge.No major complication (vascular, ventricular perforation, annular rupture, device embolization) was observed. Conclusions In this early preliminary experience stiff wire bending was able not only to keep far from the septum the wire in the majority of patients, without any complication, but also to provide wire stability and prevented inadvertent pressure of the wire over the left ventricular apex. No patient required PM implantation after TAVI. While wire bending seems promising in minimizing trauma on the conduction system, this study is to be considered hypothesis generating and more data are needed to confirm its findings.

When valve needs electrical wires - estimating pacemaker implantation after TAVR

Abstract Introduction Widespread availability and expanded indication of transcatheter aortic valve replacement (TAVR) modified paradigm of aortic stenosis. Despite elevated success rate, there are procedure related complications that need to be considered. One of the most frequent is conduction defects requiring permanent pacemaker (PPM) implantation resulting in prolonged hospital length of stay and hospitalization cost. Several risk factors for PPM implantation after TAVI have been described, and, recently, the Emory Risk Score (ERS) was developed as a predictive tool for need of new PPM implantation post-TAVI in patients who implated a balloon-expandable valve. Purpose Our objective was to evaluate risk factors associated with PPM after TAVR and to validate the ERS in our population after implantation of balloon-expandable but also self-expanding valves. Methods Retrospective, observational and single center study involving patients submitted to TAVR between 2018 and 2021. Clinical, ECG data and procedure characteristics were obtained at time of TAVR and during follow-up. The predictive discrimination of the scoring system for the risk for PPM placement after TAVR was evaluated using ROC curve analysis in SPSS Statistics. To estimate additional predictors of pacemaker implantation we used Cox proportional hazards regression models. Results From January 2018 to December 2021, 416 patients were referred to our centre for TAVR. The mean age was 82,5 ± 6,1 years, 55% female. Most frequently implanted valves were Evolut Pro and Sapien 3 ultra in 39,4% and 26,6% of pts, respectively. During follow-up 110pts (26%) needed device implantation (94 % double chamber pacemaker; 6% CRT-P or CRT-D), most frequently due to AV block. On univariate analysis, QRS width was the only factor that showed a significant correlation with pacemaker implantation (HR 1,018, 95% CI 1,007-1028; p=0.027). We found no other clinical or procedural characteristics to be predictive of PM implantation. ERS is composed of 4 variables – history of syncope, right complete branch block, QRS width &amp;gt; 140mseg and valve oversizing &amp;gt; 16% - and revealed a good sensitivity and specificity in estimating device implantation. We applied this score to our population and ROC curve analysis showed a significant prediction capacity (AUC 0,761 95% CI 0,699-0,822, p=0,031). This analysis was also performed analysing separately both subgroups of self-expandable valves (Medtronic Evolut and Evolut R) and balloon expandable valves (Edwards Sapiens). ROC curve analysis in both showed a good correlation with events – figure 1. Conclusion PM implantation is one of the most common complications following TAVR. In our population, the use of ERS displayed a very positive accuracy in predicting device implantation. Routine use of such tool can select patients at significant higher risk and thus best define patient allocation and resource utilization to reduce number of hospitalization days.

Leadless vs. transvenous single-chamber pacing - propensity-matched comparison of outcomes

Abstract Background Clinical Trials have demonstrated the safety and efficacy of the leadless pacemaker. However, real-world outcome comparisons between patients receiving conventional VVI and leadless pacemakers are still scarce. The aim of this study was to evaluate short and long-term complications of patients receiving leadless pacemakers in comparison to a population of conventional VVI. Methods We conducted a single-centre retrospective study of patients receiving the leadless or a conventional VVI between 2014 and 2022. Propensity score matching was performed on 725 patients (156 leadless and 569 conventional) and according to age, sex, coronary artery disease (CAD), chronic kidney disease (CKD), haemodialysis and AF, with a 1:1 matching protocol without replacement (matching tolerance 5%). Complications that occurred up to one month after implantation were considered acute and included access site BARC ≥ 3 bleeding events, pacemaker pocket hematoma requiring medical intervention (either drainage o antibiotic therapy), femoral access infection, pneumothorax, pericardial effusion, cardiac tamponade, and dysfunction of the implanted device. Long-term complications were defined as those occurring at least one month after implantation and included device infection, need for reintervention, and device upgrades due to left ventricular dysfunction. The primary outcome was a composite of acute and long-term complications. Results A total of 312 patients (80 [73 - 86] years, 63% male, 79% with AF and 7% on dialysis) were included, 156 within each group. The main indication for PM implantation was AF with low ventricular rate (48%), followed by atrioventricular block (31%) and sick sinus syndrome (13%). In total, 19 patients (16%) had a previously implanted device, and 14 (4%) had previously been submitted to lead extraction, of which 10 (71%) were due to device-related infection. All of these were more frequent in patients receiving the leadless pacemaker (p = 0.001). During a median follow-up of 26 [11 - 47] months, a total of 32 patients (10%) had a complication related to the implantation of the device – table 1. While intra-hospital complications showed only a tendency towards higher incidence in the VVI group (5% vs 3%; p = 0.124), overall complications (16% vs 5%) and long-term complications (12% vs 2%) were higher in the VVI group (p &amp;lt; 0.001 for both). The Kaplan-Meier curves for the primary outcome showed a significantly lower event-rate for patients receiving the leadless pacemaker – Figure 1. Conclusions In this propensity-matched study, leadless pacemaker implantation was associated with a lower incidence of complications during follow-up, in comparison to conventional VVI pacemaker.

Pacemaker dependency and conduction system recovery following transcatheter aortic valve implantation.

Transcatheter aortic valve implantation (TAVI)-related conduction system disorders are dynamic and may resolve over time. The purpose of this study was to investigate predictive factors of PM dependency among patients receiving permanent PM implantation after TAVI. We included 37 consecutive patients who underwent PPM implantation within six days after TAVI and who completed a 12-month follow-up. Patients were divided into two groups according to PPM dependency at follow-up: PPM-dependent group and non-PPM-dependent group. Device follow-ups were performed at one, six and 12 months. There were no significant differences in either baseline clinical characteristics or procedural data and results. Analysis of baseline ECGs showed a statistical difference in PR interval (200.1±17.2 ms in the PPM-dependent group vs. 175±23.3 ms in the non PPM-dependent group [P=0,003]) and in the presence of RBBB (four patients in the PPM-dependent group vs. no patients in the non PPM-dependent group [P=0.02]) as well as QRS duration (117.3±27.4 ms in the PPM-dependent group and 99±18.3 msec in the non PPM-dependent group [P=0.04]). The rate of PPM dependency was significantly reduced at 12-month follow-up: from 62,2% at the time of implantation to 35,1%. PR interval and RBBB were the most important predictive factors for PPM dependency. Persistent AVB and alternating BBB were prevalent in the PPM-dependent group. In the absence of persistent AVB or alternating BBB, we suggest that patients without long PR interval and RBBB at baseline ECG be carefully evaluated before permanent PM implantation, as conduction system recovery is possible.

Pacing-induced cardiomyopathy in patients with permanent right ventricular pacing and preserved left ventricle systolic function: characteristics, methods of treatment and prevention

The aim – to determine the frequency of occurrence and describe the characteristics of pacing-induced cardiomyopathy (PICM) in patients with permanent right ventricular pacing (at least 90 %) and preserved left ventricular ejection fraction (LVEF) (≥ 50 %).Materials and methods. The study included 34 patients with indications for permanent ventricular pacing who had pacemaker implantation from 2012 to 2022 (mean follow-up period was 44.97±28.45 months). PICM was defined as a decrease in LVEF &lt; 45 % during follow-up.Results and discussion. The incidence of PICM in this study was 26 %. The average value of LVEF and EDI at the time of the control follow-up was significantly different in the PICM group and non-PICM group: 38.6±5.9 vs. 53.5±5.7 % (p&lt;0.001) and 97.90±20.75 vs. 60.90±19.32 ml/m2 (p&lt;0.001). All patients from the study group during follow-up went through protocol echocardiography, at which intraventricular and interventricular asynchrony were examined, the number of left ventricular segments with reduced deformation were fixed, and the global longitudinal deformation of the left ventricle (GLS) was calculated. The values of these parameters differed significantly in the PICM group and non-PICM group: intraventricular asynchrony was 261.1±61.0 vs. 146.1±62.8 ms (p&lt;0.001), interventricular asynchrony 91.0±36.4 vs. 54.2±22.2 ms (p=0.014), the number of segments with reduced deformation 8.1±2.6 vs. 3.91±2.30 (p&lt;0.001), GLS -9.7±2.6 vs. -14.9±3.4 (p&lt;0.001). At the time of the follow-up examination, sensitivity on ventricular lead in the PICM group was significantly reduced compared to patients with preserved LVEF (6.26±4.02 vs. 11.56±3.86 mV; p=0.045). The paced QRS width in the PICM group was significantly greater (163.0±22.7 vs. 150.8±14.5; p=0.046) and there were more patients with rate-adapted cardiac pacing in the PICM group (4 (40 %) vs. 2 (8 %)), p=0.0305).Conclusions. According to the obtained data, cardiomyopathy due to right ventricular pacing develops rather instantaneously in the first years after PM implantation, rather than slowly progressing over time, although a multivariate regression analysis of risk factors for the development of PICM has yet to be performed on the obtained clinical data. Biventri­­­cular paicng effectively eliminates the consequences of non-physiological right ventricular myocardial paicng, improves LV systolic function. Conduction system pacing may potentially reduce the risk of right ventricular pacing-induced cardiomyopathy in patients with preserved LVEF.

Real-life data on the workload of cardiac implantable electronic device remote monitoring in a large tertiary center.

Cardiac implantable electronic devices (CIED) and implantable loop recorders (ILR) are increasingly monitored by systems allowing remote transmission of data from the patient to the hospital. Remote monitoring (RM) has been shown to increase patient satisfaction and safety. However, real-life data on the number and causes of the RM transmissions, and actions initiated by them are scarce. A total of 3446 patients with CIED and 92 patients with ILR were included in the study. Data on the number of alerts, scheduled and patient-initiated transmissions as well as the causes and actions initiated by the transmissions were systematically collected from March 1 to December 30, 2022. The data was subdivided by the device type. During the study period 7087 remote CIED and 1212 ILR transmissions were generated, (0.2 and 1.3 per patient per month), respectively. Of these transmissions 49% (4084) were automatic alerts, and 29% (2434) and 22% (1781) were scheduled and patient initiated, respectively. Most of the CIED alerts (73%) and the scheduled transmissions (90%) were nonactionable, and only 7% and 5% led to in-office follow-up, respectively. Off all ILR alerts (1011) PM implantation was scheduled to 11 patients. RM transmissions were common, but most of them were nonactionable. These real-life findings indicate that detailed analysis of the causes of the RM transmissions is important for optimization of the remote follow-up workload.

Usefulness of parahisian pacing for risk prediction of pacemaker implantation after TAVI

Abstract Funding Acknowledgements Type of funding sources: None. Background Conduction disturbances determining pacemaker implantation are a significant concern in patients undergoing Transcatheter Aortic Valve Implantation (TAVI), a procedure that is nowadays spreading even in the low-risk population. OBJECTIVE The aim of the study was to evaluate the role of the parahisian pacing, a method to directly identify the conduction system anatomical variability, in predicting the iatrogenic damage risk conditioning pacemaker implantation after TAVI. Methods Between October 2021 and November 2022 we prospectively collected clinical features, ECG, procedural and imaging data (cardiac CT and echocardiography) of every patient who underwent electrophysiological study for pre-existing or worsening conduction disorders within 48 hours after TAVI procedures in our centre. After having recorded the HV interval, parahisian stimulation at decreasing energy output was performed (CL 600 ms, 25V to 0.5V x 2 ms) with definition of the loss of capture pattern related to the three anatomical variations of His bundle described by Kawashima (1). Fisher’s exact test was used for statistical analysis; p-value &amp;lt;0.05 was considered statistically significant. Results Out of 110 TAVI performed, a total of 31 patients with conduction disorders have been studied. Patients who developed permanent 3rd degree AV block after the procedure were excluded. Mean age was 82.6±4.4 years; 21 patients (67.7%) were males. 11 patients (35.5%) had a pre-existing conduction disorder worsened after TAVI, 13 patients (41.9%) developed newly-onset LBBB; 8 (25.8%) also developed 1st degree AV block. The total number of patients who underwent PM implantation was 16 (51.6%). The anatomical variables (membranous septum &amp;lt;3mm and/or septal cusps calcifications) and type of valve implanted were not significantly associated with PM implantation (p = NS). An HV interval &amp;lt;70 ms was registered in 20 (64.5%) patients (Fig. 1); 7 of them underwent PM implantation as they developed paroxysmal 3rd degree AV block. These 7 patients all had type 2 or type 3 pattern during parahisian stimulation. None of the patients undergoing PM implantation presented a type 1 pattern during parahisian stimulation. A significant protective value (p = 0.02) for PM implantation in patients with type 1 pattern was observed (Fig. 2). Conclusions Parahisian stimulation can be a useful tool to define the conduction system anatomical variability. It can also be helpful to predict the conduction system damage risk during TAVI, conditioning PM implantation. Our data need to be confirmed in a larger population.

Feasibility and outcomes of Micra implant after cardiac implantable electronic device extraction

Abstract Funding Acknowledgements Type of funding sources: None. Background The specific and well-known design features of leadless pacing system (Micra Transcatheter Pacing System, M-TPS) have suggested his use in patients that previously underwent transvenous lead extraction (TLE) for any reason. The study aimed to investigate feasibility and long-term outcomes of M-TPS implant in patients underwent TLE. Methods Patients undergone M-TPS implantation in our Institution from May 2014 to September 2022 were included in the study. All patients fulfilled standard criteria for PM implantation (VVI or VDD mode). Follow-up (FU) was scheduled at discharge, after 1 month and every 6 months thereafter and electrical parameters were checked. Major complications were defined as life-threatening events, requiring surgical intervention or any event causing significant hemodynamic instability or resulting in death. Study population was divided between "naïve pacing" and "post-extraction" patients. Results We enrolled 193 patients (76.7% males), 57 (29.5%) received M-TPS implantation after TLE, needed because of infection in 91.4% of cases. Indications for pacing were permanent AF with bradycardia in 107 (55.5%) patients, complete AVB in 59 (30.5%), symptomatic sinus node dysfunction in 20 (10%), and advanced AVB or bifascicular bock in 7 (4%). There were no statistically significant differences between groups for demographics characteristics and primary PM implant indications, except mean age at implant that was significantly inferior in the post-extraction group [80 (IQR 75-84) vs 78 (IQR 72-83), p=0.04]. Implant procedure was successful in all and no complications were recorded. No differences between groups in procedure duration [40 (IQR 30-50) vs 45 (30-65) min, p=0.34], fluoroscopy time [9 (6-14) vs 9 (6-11) min, p=0.31] and single device delivery (64.9% vs 67.9%, p=0.35) were observed. The mean FU was 12 (1-36) months, maximum 8 years. Pacing variables at implantation [pacing threshold 0.5 (0.38-0.63) vs 0.5 (0.38-0.88) V/0.24 ms, p=0.15; impedance 720 (600-837) vs 675 (615-825) Ohm, p=0.51; R wave amplitude 9 (6.25-12.87) vs 8.2 (5.65-12) mV, p=0.47], discharge [pacing threshold 0.38 (0.38-0.63) vs 0.38 (0.38-0.63) V/0.24 ms, p=0.27; impedance 685 (580-770) vs 610 (560-750) Ohm, p=0.16; R wave amplitude 10.25 (7.2-14.5) vs 9.3 (6.5-16.5) mV, p=0.6], and at 6 months [pacing threshold 0.5 (0.38-0.5) vs 0.5 (0.38-1.25) V/0.24 ms, p=0.64; impedance 580 (520-680) vs 570 (510-640) Ohm, p=0.63; R wave amplitude 11.9 (8.2-16.4) vs 11.7 (9-20) mV, p=0.68; battery voltage 3.09 (3.05-3.11) vs 3.09 (3.04-3.13) V, p=0.71] did not show differences. Conclusion M-TPS is an efficacious and safe alternative to conventional PM, with the main advantage of the absence of transvenous leads and a surgically created subcutaneous pocket, avoiding all the related complications. These devices are a reliable alternative after TLE, with similar electrical performances than those observed in patients who did not previously received pacing.

P296 WHAT IF CARDIAC SURGEONS PERFORM TRANS–CATHETER AORTIC VALVE INTERVENTIONS?

Abstract Background and aim Aim of this study is to present the results of our aortic valve interventions program embedding surgical (SAVR) and trans–catheter treatment, both in the hands of cardiac surgeons. Methods Data of patients who had isolated aortic valve interventions during the period 2016–2022 were reviewed. SAVR was performed mainly through a minimally invasive approach . TAVI included either TF or TA access procedures, all performed in a cardiac surgery theatre with fluoroscopy equipment. Results During the study period, 1435 patients underwent isolated aortic valve intervention: 1022 surgical AVR (665 mini AVR, 357 FS) and 413 TAVI (333 TF and 80 TA). TAVI were introduced during 2018 and gained a wider application over the years with the progressive adoption of awake procedures and fully percutaneous access (Figure 1). The global volume of aortic valve procedures increased of 38% comparing the full–years 2021 with 2018 (295 vs 213 cases). Multivariable logistic regression showed that TAVI was significantly associated with increased age, female gender, a higher rate of comorbidities and lower LVEF. Overall in–hospital mortality was 0.6% – mini AVR 0.3%, FS 0.3%, TF TAVI 1% and TA TAVI 3%. Permanent neurologic injury was recorded in 0.7% of the patients. Permanent PM implantation was higher after TAVI (87/413 vs 32/1022 patients who had surgical AVR). Conclusions TAVI procedures can be safely performed by cardiac surgeons. The expertise in both surgical and trans–catheter treatment translated in the possibility of treating aortic valve disease in a higher volume of patients including older and comorbid patients with excellent early results.

P22 AN UNEXPECTED DIAGNOSIS; GEMELLA MORBILLORUM, A POORLY KNOWN KILLER

Abstract 58–year–old woman, previous smoking habit. In medical history holosystolic murmur since childhood. At echocardiogram performed in 2019: "VS with preserved FE, mild–to–moderate IA, likely perimembranous DIV." No major comorbidities. In June 2021, she was admitted to the Mestre NICU for paroxysmal complete atrioventricular block. On echocardiogram, mild worsening of IA was described, with a sub–valvular shunt and doubtful aortic bicuspidia. At 24 hours after admission, the patient underwent definitive bicameral PM implantation. In light of the clinical and echocardiographic suspicious, we began to think of a possible organic genesis of the event; a hypothesis supported by the finding of serotin fever and a dental examination with dental hygiene that the patient reported having performed a month earlier. So, on suspicion of an infectious genesis, cold blood cultures were requested and found to be positive for Gemella Morbillorum. The endocarditis hypothesis was confirmed by performing a TE echo and PET/CT scan. Antibiotic therapy was then set up, and an infectious source was subsequently searched for, through a CT scan of the dental arches, which was positive for foci of periodontopathy, and through a rectosigmoidocolonoscopy finding an adenoma with high–grade dysplasia. HOT TOPIC: infective endocarditis is a disease with a high risk of mortality and complications. Among the complications, conduction disturbances are relatively rare. A–V block is often paroxysmal, driven by inflammation, and therefore potentially reversible. Hence, the paramount importance of performing a thorough echocardiogram and resolving any suspicions before referring the patient for definitive device implantation. The case also turns out to be particularly interesting not only for the onset of symptomatology but also for the etiology of the latter. In fact, the microorganism responsible is not among the most frequent germs but represents a rare cause of which there are few cases described in the literature. The main infectious source in humans is the dental system, but several studies have shown a correlation between Gemella morbillorum and rectal colon cancer. Ultimately, the above case represents a typical example of how a "easy" hospitalization for a conduction disorder can actually reveal a much more complex pathology.

P277 MULTIFACTORIAL RECURRENT CHYLOUS ASCITES: THE CASE REPORT OF A PATIENT WITH HEART FAILURE WITH PRESERVED EJECTION FRACTION (HFPEF), LIVER DISEASE AND PAST ABDOMINAL SURGERY

Abstract Chylous ascites is the accumulation of triglyceride–rich fluid in abdominal cavity. It is caused by lymphatic ducts injury, usually as consequence of surgery, neoplasia, or infection. Rarely, it can also occur from heart failure, pericarditis, or cirrhosis. We report the case of a 66–year–old man electively hospitalized for acute renal failure and anasarca state. The cardiological history was significant due to acute myocardial infarction treated with CABG, PM implantation for complete AV block, atrial fibrillation, and type 2 diabetes mellitus. The entero–hepatological history started in 2019 when, two months after abdominal surgery for an incarcerated hernia, he developed chylous ascites and chylotorax. Starting from 2021, the patient presented recurrent episodes of tense ascites, requiring periodic paracentesis. Haematological and infectious disease evaluation resulted negative, liver biopsy showed congestive hepatopathy with fibrosis, while venous catheterization found high right filling pressure with not portal hypertension. Patient was treated with Apixaban 2.5 mg b.i.d., Furosemide 50 mg b.i.d., Metformin 1500 mg, Enalapril 20 mg, and Simvastatin 20 mg. During the hospitalization other paracentesis confirmed the chylous nature of the effusion, echocardiography (despite very bad acoustic windows) showed preserved left ventricle systolic function (LVEF 55%), 3rd degree LV diastolic disfunction, and dilatation of right ventricle, atria, and inferior Vena Cava. Right heart catheterization confirmed the presence of LV restrictive physiology, combined pulmonary hypertension, and ruled out the diagnosis of constrictive pericarditis. In hospital treatment focused on resolving acute renal failure and hypervolemia through intravenous diuretic and Albumin and on optimizing cardiological therapy. The patient was discharged with the following treatment: Apixaban 2.5 mg b.i.d., Furosemide 50 mg b.i.d., Canrenone 100 mg b.i.d., Empagliflozin 10 mg, Simvastatin 20 mg, and indication to hypo–lipidic diet. This case highlights how the coexistence of different predisposing factors of chylous ascites (past abdominal surgery, heart failure and liver disease) can amplify each other. Recognizing the single role of each of them is of pivotal importance to elaborate targeted treatment. Moreover, in literature, there are some cases of chylous ascites associated with constrictive pericarditis and with severe heart failure, but to our knowledge not with coexistence of HFpEF.

P186 LEADLESS PACEMAKER VERSUS TRANSVENOUS PACEMAKER: THE BEST ALTERNATIVE FOR THE POST–EXTRACTION PATIENT

Abstract Introduction As complications associated with pacemakers or defibrillators implant increase, the number of patients undergoing transvenous lead extraction following infection has increased. This study aims to compare follow–up and to evaluate the incidence of reinfection between post–extracted patients re–implanted with leadless pacemakers and post–extracted patients re–implanted with transvenous device. Materials and Methods From December 2016 to October 2022, 163 patients underwent transvenous lead extraction in our center. Of these patients, 24 were subsequently reimplanted with a leadless pacemaker, while 52 with a traditional device. Instead, 11 were reimplanted with S–ICD, 3 with a loop recorder; 73 are patients who, after cardiological re–evaluation, either didn’t reimplant a new device or were redirected to the first implant center. For each patient has been evaluated the efficacy of the reimplanted device, the appearance of any minor or major complications, the recurrence of infection. Results About the 24 post–extracted patients who were reimplanted with a leadless pacemaker, in no case there was a recurrence of infection and/or complications associated with the device. In the 52 post–extracted patients reimplanted with a traditional device, only 1 case experienced a recurrence of infection (0.02% rate). If we analyze this last class better, we see how in the past some of these had already undergone a pocket overhaul or an extraction of first implant device. Many are also patients with leads abandoned by another center and with new device’s infection. Conclusions Leadless PM implantation in post–extracted patients, when we have patients eligible for this device, proved to be an effective choice in reducing re–infection recurrences compared to the population of patients reimplanted with a transvenous device. However, if we consider the low rate of reinfection in patients re–implanted with transvenous device, we can say that when the patient is well prepared and the implant prophylaxis is correct, the recurrence of infection is low even if one decides to re–implant a traditional device.

P97 AORTIC PSEUDOANEURYSM AS PRESENTATION OF INFECTIVE ENDOCARDITIS FOLLOWING VALVE IN VALVE TAVR: THE IMPORTANCE OF A MULTIMODAL DIAGNOSTIC APPROACH

Abstract Transcatheter aortic valve implantation complicated by infectious endocarditis (TAVI–IE) is an uncommon clinical event with a death rate of 24–46%. Despite several risk factors (young age, sex male, CKD, concurrent PM implantation, residual aortic insufficiency and valve–in–valve implantation) have been reported, the identification of this clinical scenario remains a diagnostic challange due to less sensivity and specificity of echocardiography ascribed to possible imaging artifacts or to a localization of the infectious process that cannot always be evalueted. Clinical case Sixty day after TAVI valve–in–valve procedure, during a rehabilitation recovery, an 80 years old female patient presented intermitted fever with an elevation of flogosis index. In suspicion of urinary tract infection, antibiotic therapy with ciprofloxacin has been started and at the same time the patient has been transferred to our center. At the admission time a blood colture resulted positive for Staphylococcus epidermidis. A complete echocardiogram(TTE+TEE) has been performed and showed an aortic bioprothesis with normal morphology, position and shape and normal gradient at continuos doppler analysis(17/30 mmHg). The distal part of the ascending aorta has not been evalueted due to a masking phenomenon caused by prostetich cage artifact. Considering the high probability of infective endocarditis, a chest CT was performed and showed a 22x11x18mm pseudoaneurism in the extreme distal point of the cranial part of the prosthesis. Therefore, the patient underwent to an emergency cardiac surgery with replacement of the ascending aorta with a prosthetic graft and the aortic valve with a new bioprothesis. The diagnosis of infected pseudoaneurysm was confirmed by the hystologic examination and after 22 days since the intervention, the patient was transferred to the sending rehabilitation center with an indication to continue Daptomicin therapy, started during the recovery, for 6 weeks. Even with non–suggestive ecocardiographic evidence, the presence of positive blood colture test in patients with endocarditis risk factors, need a multimodal imaging approach to diagnosis (for instance, CT or PET) in order to provide prompt and appropriate therapy.

P96 NO PATIENT SELECTION IN TOTALLY ENDOSCOPIC ISOLATED MITRAL VALVE SURGERY: OPERATIVE AND EARLY RESULTS IN DEGENERATIVE MITRAL VALVE REGURGITATION

Abstract Background and aim In high–volume centers MICS can be offered to any patient affected by degenerative mitral valve surgery (MVS). Aim of this study was to evaluate early outcomes in patients undergoing isolated MVS for degenerative mitral regurgitation (MR) using a totally endoscopic technique. Methods From January 2018 to December 2022, 1124 consecutive unselected patients underwent endoscopic MVS at our institution. Among them, 399 patients underwent isolated MVS for degenerative valve pathology. Concomitant surgery and different etiology were excluded. All patients were approached with peripheral cannulation, limited skin incision (peri–areolar/sub–mammary/anterior axillary line) and 5 mm 30° endoscope. Neo–chordae implantation plus annuloplasty ring was the preferred technique for mitral repair. Results Endoscopic MVS was achieved in all patients and no conversion to sternotomy was needed. Median Cross–Clamp and CPB Time were respectively 93 [75 – 11] and 143 minutes [115 – 171]. Overall in hospital mortality was 0.75%. Major Stroke occurred in 1.6%. Replacement for unsuccessful repair occurred in 4 patients (1%). Repeated cross–clamp for residual MR in 13 patients (3,3%). Median intubation time was 5 h [3 – 7], ICU time was 18 h [15 – 21], bleeding requiring revision occurred in 21 patients (5.3%) always through the same access. PM implantation occurred in 3%, vascular complications in 1%. We had 1 case of endocarditis, 1 case of early failure, 1.3% mitral redo. Conclusions In high volume centers isolated endoscopic MVS without preoperative patient selection has proven to be safe with optimal mortality, good fast–track and low incidence of complications.

1155 CORONARY ARTERY DISEASE AND SEVERE AORTIC STENOSIS IN THE COVID-19 ERA: A CASE REPORT

Abstract An 81-years-old with a history of hypertension, dyslipidemia, and chronic ischemic heart disease with prior stent implantation of right coronary artery in 2011. Due to its poor compliance, no recurrent symptoms, and, finally, the COVID-19 pandemic, the patient did not perform any cardiological follow-up during these years. Unfortunately, the last six months he has reported the onset of dyspnea and typical angina due to moderate efforts, undervalued by the patient. Because of the rapid worsening of dyspnea and typical angina in the last 5 days, he went to the local emergency department (ED). The role in/role out routine exams performed in the ED documented a COVID-19 infection. At the ED, his vital signs were normal, with a blood pressure of 135/75 mm Hg, heart rate of 74 regular beats/min, body temperature of 36.5 °C, oxygen saturation of 97% in ambient air, and respiratory rate of 16/min. Of note, the chest x-ray was normal, as well as no alterations were documented at the CT scan performed a few hours later. First-line blood sample tests were within range except for Hb 10 mg/dl. Therefore, a cardiological evaluation was requested. Electrocardiogram (ECG) showed inverted T-waves in V1-4 leads, and echocardiography showed normal left ventricular ejection fraction (FE 55% Simpson), left ventricular anterolateral wall hypokinesia, and severe aortic stenosis (V max 4.78 m/s, Gr max 4.78 m/s, Gr medium 59 mmHg). Since myocardial necrosis enzymes were increased (T-hs 118.7 ng/dl; CK-MB 6.3 ng/L; NT-ProBNP 761 ng/dl), leading to the suspicion of acute coronary syndrome the patient underwent coronary angiography, showing critical stenoses of the left descending artery (LAD), circumflex (LCX), I obtuse marginal (IOM), and patent stent of the right coronary artery. Therefore, the Heart team deemed the patient at high operatory risk choosing, in agreement with the patient, for a percutaneous coronary intervention (PCI) followed by TAVR. Accordingly, the patients underwent PCI of LAD with the implantation of a Xience-Serra 3.0×15 mm and PCI of LCX with the implantation of an Onyx 2.75×18 mm stent. After COVID -19 resolution, which happen 7 days later, the patient was moved to our cardiology department. Two days later in the same procedure, we performed the first PCI of I-OM with the implantation of a Xience Sierra 3.0×18 mm stent following a TAVI with the implantation of Evolute Pro valve 29 mm. The post-procedure echocardiogram showed an optimal valve position with a transvalvular mean pressure gradient of 4 mm Hg. After six days post-TAVI, for a complete atrioventricular block, the patient also underwent a pacemaker implantation. The patient was finally discharged after 10 from TAVI. Discussion This case report offers several foods for thought. First, the COVID-19 pandemic has negatively affected primary and secondary prevention, even for patients affected by cardiovascular disease. Our patient has postponed clinical checks even when the symptoms reappeared, also because of the concerns lead by the COVID-19 pandemic. Second, completeness and timing of coronary disease revascularization, which in this case was staged and performed before TAVI. Finally, the late occurrence of advanced heart block requiring PM implantation. For instance, in an era of fast-track TAVI, more studies are warranted to identify patients who are at higher risk of late PM implantation.

594 HIDDEN CAUSES FOR UNEXPLAINED SINCOPE

Abstract Bicuspid aortic valve (BAV) is a congenital cardiac abnormality, affecting approximately 1%-2% of the general population (male &amp;gt; female). A 33-year-old man was admitted to emergency department (ED) for syncope during exertion. He had a history of cigarette smoking with a known previously discovered BAV with mild stenosis. TTE showed a severely calcified bicuspid aortic valve with severe stenosis and regurgitation. ECGs showed frequent asymptomatic complete hearth block (CHB), unresponsive to isoprenaline infusion. He underwent ministernotomy aortic valve replacement (AVR) with mechanical valve. During hospital stay, the 24h ECG telemetric monitoring did not show any A-V disturbance and TTE demonstrated normal prosthesis function. Pacemaker implantation was delayed, Follow-up was performed at 1, 6 and 10 months after surgery: 24h-ECG recordings were performed showing no A-V conduction disturbances. At 1 year, during routine medical screening, cardiac frequency of 38 bpm was detected (ECG revealed sinus rhythm with CHB and junctional escape rhythm of 38 bpm). ICCU echocardiogram showed good ventricular and prosthesis function. Therefore, a dual-chamber MRI compatible pacemaker was implanted. Few cases are reported in literature of young patients presenting with A-V block having a severely calcified aortic bicuspid valve. Their management is poorly explored, and therapies (medical therapy, aortic valve replacement and pacemaker implantation) are not fully evidence based. In literature, 3 cases of possible reversibility of conducting system disorders after severe stenotic aortic valve surgery are described. Noninvasive strategy was initially successful as demonstrated by both the post-operative absence of any AV conduction disturbance and/or symptoms and the close follow-up monitoring. Despite of previous evidence, our experience demonstrates that a complete heart block can recur following aortic valve surgery, even in young patients. Initial presentation of CHB was intermittent, suggesting that the structural damage to the conducting system could not be irreversible; thus, it could positively respond to valve surgery. Unfortunately, in CHB with calcific aortic stenosis patients should be considered for PM implantation at the time of aortic surgery. When a waiting strategy prevails, especially for young patients, close monitoring and follow-up must be warranted to early detect A-V disturbances recurrence.

968 LYME CARDITIS: COMPLETE AV DISSOCIATION PRESENTING AS DYSPNEA IN THE EMERGENCY DEPARTMENT

Abstract Background Lyme carditis (LC), an early disseminated manifestation of Lyme disease, has important clinical implications for patients. High-degree atrioventricular block is the most common presentation of LC, and usually resolves with antibiotic therapy. Clinical case A 31 years-old man without remote pathological history and cardiovascular risk factors presents for resting dyspnea. In the EKG, findings of paroxysms third-degree atrioventricular block with a junctional escape rhythm were found. No abnormalities found on the transthoracic echocardiogram. After the tick bite reported about 1-2 months earlier, given the suspicion of Lyme carditis, serology for Borrelia Burgdoferi was tested, which was then positive, and empirical antibiotic therapy has been initiated. During the EKG monitoring, paroxysms of second-degree type I atrioventricular block and first-degree AVB were relevated. In few days, we assisted to a complete retrieval of normal atrioventricular conduction. Therefore, a loop recorder was implanted, cardiac resonance was performed and then discharged. About 4 weeks later the patient performed a stress test on the cycloergometer to identify frequency-dependent atrioventricular blocks, which was then negative. Rationale The suspicion and the early diagnosis of Lyme carditis is fundamental to identify this unusual transient condition, thus preventing unnecessary PM implantation in otherwise healthy young individuals.

678 WIDE COMPLEX TACHYCARDIA IN A PATIENT TREATED WITH PERMANENT HIS BUNDLE PACING: A CASE REPORT

Abstract Introduction Differential diagnosis of wide complex tachycardias based only on ECG analysis remains a challenging exercise. But, when intracardiac tracings are available (i.e., pacemaker EGM), electrophysiologists may consider several tricks to make a correct diagnosis. Case Presentation A 73-years-old sporty male was admitted to our hospital for palpitations and dizziness. ECG monitoring revealed AF, typical atrial flutter and asystolic pauses following spontaneous cardioversion of atrial arrhythmias. We diagnosed sick sinus syndrome and implanted a dual-chamber pacemaker with an atrial lead in the right appendage and a stylet-directed active fixation lead in the His region, obtaining non-selective narrow paced QRS. The day after PM implantation, during a new episode of AF, two runs of regular wide-complex tachycardia (LBBB morphology, cycle length of 270 ms) occurred (Fig 1A, B). LBBB morphology, patient's history, and AF favored aberrancy, but couldn't exclude VT or preexcitation (by atrio-fascicular AP). Our diagnostic strategy consisted in adding atrial and His intracardiac electrograms registered by pacemaker to analysis of ECG traces. The device interrogation showed AV dissociation at the time of the wide complex tachyarrhythmia and a negative HV interval (Fig. 2A). These findings ruled out aberrant ventricular conduction and bundle branch reentrant tachycardia, because both these arrhythmias are characterized by HV ≥ HV in sinus rhythm. We performed incremental atrial pacing maneuver, during SR, obtaining decremental AH conduction with constant HV interval (60 ms), excluding atrio-fascicular, nodo-fascicular and nodo-ventricular AP. His bundle activity was identified just after the ventricular activation, producing a relatively short VH interval, suggesting the presence of a retrograde activation of the His bundle, therefore it was possible to hypothesize that the site of origin of the ventricular arrhythmia was within/or very close to RBB (Fig 2B, C). Just in few beats His bundle deflection was missing, probably because of recovery of functional LBBB (Fig 2D). Discussion Our final diagnosis was RBB VT. Patient was treated with Verapamil 80 mg t.i.d., with no further recurrence. This case highlights the diagnostic value of device interrogation in patients with permanent His bundle pacing, for the evaluation of wide complex tachycardias.