P228 WEARABLE DEFIBRILLATOR IN CLINICAL PRACTICE. MULTIANNUAL MULTI–CENTER EXPERIENCE

Introduction

Heart failure with reduced left ventricular ejection function (LVEF) represents a life–threatening condition for patients (pts). A period of time of 40–90 days, in optimal medical therapy, is indicated to evaluate the recovery of the LVEF and the indication to ICD implantation. In this period, from 1% to 5% of pts can experience sudden death. We evaluated the usefulness of the wearable cardioverter defibrillator (WCD) as a temporary antiarrhythmic therapy in the interval from discharge to the three–month follow–up.

Methods

From December 2015 to December 2021, 174 consecutive pts (141 M (81%); mean age 62 years ± 11.6 years) were discharged with reduced FE < 35% in OMT, with WCD and were re–evaluated within 3 months to establish indication for ICD implantation.

Results

110 pts (63.2%) recovered LVEF at 3 months and left the indication to ICD. 9 pts refused and/or returned the WCD due to poor compliance (5.2%); 52 pts (29.9%) did not recover LVEF and were implanted with ICD. The WCD was worn continuously by the majority of pts with good compliance for 87.4 ± 52.0 days (range 1 ÷ 303 days), for 22.08 hours / day. 23 episodes of AF were correctly recognized; 10 TVNS> 10 sec; 1 episode of VF in 1 patient in which 1 shock was correctly delivered. 1 inappropriate shock was delivered on tachycardic AF. During the WCD wearing period, 3 deaths occurred (1.7%): in 2 pts due to refractory HF (one of these pts had VF correctly recognized and treated by the WCD but degenerated into pulseless activities); 1 death for terminal cancer). The use of WCD has progressively increased over the years (from 4.5 LV / yy in 2015–16 to 45 LV / yy in 2020–21).

Conclusions

The use of WCD has gradually increased in clinical practice for patients who have not yet developed clear indications for ICD implantation. In the majority of them, ventricular dysfunction is transient. Wearable cardioverter defibrillator represents additional security during this period. Continuous monitoring makes it possible to identify supraventricular and ventricular arrhythmias, improving therapeutic appropriateness and in general the patients have excellent compliance with the device. Further studies are needed to substantiate this strategy.

P32 SELF–LEARN IMPLEMENTATION OF ULTRASOUND FOR THE STUDY AND ULTRASOUND–GUIDED PUNCTURE OF VASCULAR ACCESSES IN THE IMPLANTATION OF PACEMAKERS AND IMPLANTABLE DEFIBRILLATORS

Background

The vascular access represents a crucial phase in the management of complications related to the implantation of devices. After the use of the axillary vein, which allows the elimination of intrathoracic complications as well as the subclavian crush of the catheters, the ultrasound–guided approach could represent the next step for the reduction of vascular complications.

Experience

All implants performed (n = 86) by an independent operator who implemented ultrasound to minimize complications related to central access were reviewed. During the first phase, the ultrasound–guided approach involved the study of vascular accesses before the start of the implant. The assessment took place before the preparation of the sterile field, for the localization of the axillary approach and for the study of the anatomical variants. It was immediately followed by the use of skin marks. The use of markers made it possible to attempt surgical isolation of the cephalic vein as a first approach. In case of failure, or the need for multiple accesses, the transition to central access could be facilitated by the presence of skin markers. This approach have not significantly modified the probability of successful axillary vein puncture without the use of venography (75% vs 71%, p NS). In the last phase all implants were performed with ultrasound–guided puncture with sterile technique before skin incision (n = 26). The procedures involved dual chamber (61%), single chamber (19%), CRTD (11%), dual chamber ICD. Ultrasound showed all cases of hypoplastic cephalic vein (15%). In the first three months of implementation, the success rate was 71.4% with 1 self–healing case of apical pneumothorax. In the following months the success rate rapidly increased to 94.1% (p < 0.05) with no pneumo or hemothorax. The median time to effective puncture was 28 seconds (8–450sec) in the second phase. It was possible to isolate the cephalic vein in 40% of cases for two or three chamber implants.

Conclusions

The ultrasound study of the accesses performed before the incision allows to identify the anatomy and to define the course of the axillary vascular system and its relationships. When performed with a sterile approach, it allows direct ultrasound–guided puncture before the surgical incision, with a high success rate from the early stages of implementation.

P1470Outcome of leadless pacemaker implantation in a referral centre for lead extraction: a comparison with transvenous pacemaker

Background

Leadless cardiac pacing is a promising technology in terms of efficacy and safety.

Purpose

The aim of the study was to compare the long-term clinical and electrical performance of Micra leadless pacemaker with ventricular single-chamber transvenous pacemaker (VVI TV-PM) in a high-volume centre for transvenous lead extraction (TLE).

Methods

Between May 2014 and April 2019, 100 patients (group 1) underwent Micra implant at our centre. We identified 100 patients (group 2) who underwent VVI TV-PM implant in the same period for a 1:1 comparison matched by age, sex, left ventricular systolic ejection fraction and  previous TLE.

Results

The implant procedure was successful in all patients. In group 1, the procedure duration was lower than in group 2 (43.86 ± 22.38 vs 58.38 ± 17.85 min, p < 0.001), while the fluoroscopy time was longer (12.25 ± 6.84 vs 5.32 ± 4.42 min, p < 0.001). There was no difference about the rate of septal deployment at the right ventricle (group 1 vs group 2: 76% vs 86%, p = 0.10). Patients were followed-up for a median of 12 months. We did not observe any acute and chronic procedure-related complications in group 1, while we reported acute complications in seven patients (0 vs 7%, p = 0.02) and long-term complications in three patients (0 vs 3%, p = 0.24), needing for a system revisions in 6 cases (0 vs 6%, p = 0.038) in group 2. One systemic infection occurred during follow-up in a patient with VVI TV-PM. Electrical measurements were stable during follow-up in both groups, with a longer estimated battery life in group 1 (mean delivered energy at implant group 1 vs group 2: 0.14 ± 0.21 vs 0.26 ± 0.22 μJ, p < 0.001).

Conclusion

Micra pacemaker implant is a safe and effective procedure, with a lower rate of acute complications and system revisions and a longer estimated battery life compared to VVI TV-PM, even in a real life setting including patients who underwent TLE.

P1469Micra pacemaker implant at septal site induces a smaller increase on qrs duration than traditional pacemaker: a single center experience

BACKGROUND

Leadless pacemakers have been introduced into the clinical practice as a breakthrough technology that could tackle most of the major sources of complication of traditional pacemakers (PM). The excellent safety profile and optimal electrical performance of Micra have been already largely described, nevertheless the impact on QRS duration has not been investigated so far. We aimed to compare changes in QRS duration after septal Micra implant in comparison to patients who received transvenous right ventricular leads in the same position.

METHODS

We enrolled all patients who underwent Micra implantation (group 1) at our Center from April 2017 to March 2019. A septal placement was attempted in all cases. Duration of spontaneous and paced QRS and their difference (delta QRS) were measured using a polygraph. To provide a comparison group, we analyzed the QRS duration in a matched group of patients (group 2) who received a traditional single chamber pacing system with a transvenously implanted lead at septal position in the same period. Confounding variables that were used to provide the control group were age, sex, left ventricle ejection fraction, and rhythm at implant. High pacing threshold was defined as ≥1.0 V at pulse duration of 0.24 ms.

RESULTS

Twenty-eight consecutive patients (mean age 78 ± 3 years; 71.43% males) who underwent successful Micra implant were enrolled. A septal position was achieved in all cases with a single device delivery in 17/28 patients (60.7%). Mean pacing threshold at implant was 0.56 ± 0.34V/0.24 ms with only 3/28 patients (10.7%) presenting a high pacing threshold. No significant differences in demographic, clinical characteristics and ventricular pacing site were observed between groups. QRS duration was slightly longer in group 1 compared to group 2 before implant (median 123 ms (IQR 104-146.5 ms) vs median 116 ms (IQR 90-125 ms); p = 0.09). Nevertheless, there was a significantly lower delta QRS after implant in Micra compared to the traditional pacing group (15.82 ± 31.77 ms vs 35.82 ± 22.13 ms, p = 0.008).

CONCLUSION

Right ventricular stimulation induces ventricular dyssynchrony, which is correlated with the amount of QRS enlargement after pacing. Micra implant, in a non-apical position, produces significantly smaller changes on the QRS duration in comparison with transvenous lead implanted at the same site, although larger studies are necessary to confirm these results.

1260Transvenous lead extraction: efficacy and safety of the procedure in octogenarian patients

Introduction

the management of patients with infection or malfunction of a cardiac implantable electronic device (CIED) may be challenging.

Purpose

The aim of the study is to evaluate the safety and efficacy of transvenous lead extraction (TLE) in elderly patients.

Methods

a retrospective analysis of patients who underwent to TLE in our center was performed. Patients were divided in two groups: 1) patients 80 years of age or older, 2) patients younger than 80 years. All patients were treated with manual traction or mechanical dilatation.

Results

our analysis included 1316 patients, with a total of 2513 leads extracted. Group 1 (≥80 years) counted 202 patients and group 2 (<80 years) 1114 patients. The group of elderly patients presented more comorbidities, as hypertension, chronic kidney disease, atrial fibrillation and pulmonary disease. Patients 80 years of age or older had more pacemakers than ICDs, whereas the dwelling time of the oldest lead, the number of leads and the presence of abandoned leads was similar despite patients age. In group 1 the rate of radiological success for lead was higher than in group 2 (99.0% vs 95.9%; P < 0.001). The clinical success was obtained in 1273 patients (96.7%), without significative differences between groups (98.0% vs 96.4%; P = 0.36). Major complications occurred in 10 patients (0.7%), without significative differences (1.5% vs 0.6%; P = 0.24) (figure 1).

Conclusion

TLE in elderly patients is a safe and effective procedure. In patients older than 80 years there are not more major complications than in younger patients, and the efficacy of the procedure seems to be superior.

Abstract Figure 1

P1358Atrial electromechanical interval in patients with arrhythmias: is everyone the same?

Background

Atrial electromechanical delay, assessed calculating the PA-TDI interval using tissue Doppler imaging, is a known and promising determinant for atrial fibrillation recurrence prediction after pulmonary vein isolation and electrical cardioversion.

Purpose

To determine the relationship between atrial electromechanical delay and the presence of atrial fibrillation.

Methods

We prospectively enrolled patients presenting at our Unit in sinus rhythm scheduled for an arrhythmogenic substrate ablation (atrial fibrillation -AF-, supraventricular tachycardia -SVT- and premature ventricular contractions -PVC-). Demographic and echocardiographic characteristics were evaluated upon admission. Atrial electromechanical delay was inferred via the PA-TDI interval, obtained by calculating the time difference between the P wave onset and the A" wave peak on TDI recordings.

Results

From October 2018 to August 2019, 200 patients (60% male, mean age 58,21 ± 14,26, mean BSA 1,9 ± 0,21 m2, mean BMI 26,42 ± 6,28 kg/m2, mean EF 60,91% ± 5,43%) were admitted to our unit to undergo AF (group 1: n = 145; 72,50%), SVT or PVC ablation (group 2: n = 55; 27,5%). Compared with the control group (group 2), patients admitted for AF ablation had a larger LA size (group 1 vs group 2: mean LA area 23,21 ± 5,07 vs 16,87 ± 4,01 cm2, p < 0,001; mean indexed LA volume 46,71 ± 20,41 ml vs 32,04 ± 14,7 ml, p < 0,001; mean LAD 41,77 ± 5,66 vs 33,84 ± 6,06, p < 0,001) and a longer PA-TDI interval (lateral 148,55 ± 28,5 vs 128,57 ± 20,9, p < 0,001; medial 125,34 ± 21,02 vs 109,11 ± 21,49, p < 0,001; average 141,43 ± 27,58 vs 119,08 ± 18,63, p < 0,001).

Conclusion

The PA-TDI interval is a non-invasive and easily achievable echocardiographic parameter, which is demonstrated to be prolonged in patients with a history of AF in contrast with patients with other arrhythmias, as expression of atrial conduction heterogeneity.

Abstract Figure. PA-TDI measurement

P2836Role of pre-procedural CT-imaging on catheter ablation in patients with atrial fibrillation: procedural outcomes and radiological exposure

Introduction

Cardiac computerized tomography (CT) is commonly used to study left atrial (LA) and pulmonary veins (PVs) anatomy before atrial fibrillation (AF) ablation. However, it remains unclear whether pre-procedural imaging actually is associated with an improvement of efficiency, efficacy, and safety.

Purpose

Aim of the the study was to determine the impact of pre-procedural imaging using CT with 3-D reconstruction on procedural outcomes and radiological exposure in patients who undergo radiofrequency catheter ablation (RFA) to eliminate AF.

Methods

In this registry, 493 consecutive patients (age 62±8 years, 70% male) with paroxysmal (316) or persistent (177) AF who underwent RFA were included. A CT scan was obtained in 324 (66%) patients (CT Group) prior to RFA, while 169 (34%) didn't have any pre-procedural imaging (No-CT Group). Antral PVs isolation was performed in all patients along using an open-irrigation-tip catheter with a 3-D electroanatomical navigation system. Additional ablation applications were targeted if required. Procedural outcome, including radiological exposure, and clinical outcomes were compared among patients who underwent RFA with (CT-Group) and without (No CT-Group) pre-procedural imaging.

Results

Acute PV isolation was obtained in all patients. Additional ablation targets were targeted along the CTI (71/324 [22%] vs. 40/169 [24%], P=NS), the roof line (74/324 [23%] vs. 40/169 [24%], P=NS), the mitral isthmus (33/324 [10%] vs. 12/169 [7%], P=NS) and CFAEs (28/324 [8.6%] vs. 12/169 [7.1%], P=NS), without significant differences among groups. Complication rate were comparable between CT and No CT patients (4.3% vs 3%, P=0.7). In one Redo procedure of the No-CT Group, for the impossibility of identifying left PVs, a 3D LA fluoro-angiography was performed, which confirmed a left PVs occlusion. (Figure) No differences were observed about mean duration of the procedure (231±60 vs 233±58 min, P=0.7) and fluoroscopy time (13±10 vs 13±8 min, P=0.6) between groups. Cumulative radiation dose resulted significantly higher in the CT-Group (8.9±24 vs 4.8±15 mSV, P=0.02). Compared to paroxistical AF, persistent AF patients showed a comparable procedural-ED (6.6±26 vs 6±19, P=0.8) but with an higher CT-ED (1.7±2.9 vs 1.1±1.9, P=0.01).At 1 year, 227/324 (70%) and 119/169 (70%) of the patients who did and did not have pre-procedural imaging were free from AF (P = NS).

Figure 1

Conclusions

Pre-procedural CT does not improve safety and efficacy of AF ablation, increasing significantly the cumulative radiological exposure. Considering that patients candidate to AF ablation are often young, the cumulative radiation dose per life span and radiation dose reduction strategies should remain a matter of concern for doctors.

Acknowledgement/Funding

None