Biventricular Implantable Cardioverter-defibrillator Research Articles

Abstract 15242: The Flipside of Flecainide: A Case of Flecainide Induced Loss of Capture

Introduction: Flecainide is a class 1c anti-arrhythmic agent that slows phase 0 of the fast inward sodium (Na) channels in a rate-dependent fashion leading to decreased conduction velocity in the His-Purkinje and ventricular myocardium. Its high affinity and slow unbinding prolong QRS duration on electrocardiogram (EKG). Partial renal excretion and a narrow therapeutic index of 0.2-1mcg/mL can cause drug toxicity. Case: A 72-year-old woman presented with palpitations and weakness. She had a history of non-ischemic cardiomyopathy, biventricular (BiV) implantable cardioverter defibrillator, frequent premature ventricular contractions on flecainide 100 mg twice a day, and chronic kidney disease. She was hypotensive and with acute kidney injury. EKG showed wide complex ventricular rhythm, QRS duration of 305 ms and intermittent ventricular pacing (Fig.1A), changed since EKG 6 months ago (Fig.1B). Device interrogation revealed normal sensing and impedances but failure to capture from all 3 leads. She had stable lead parameters and appropriate BiV pacing 6 months ago. Chest X ray showed stable lead positions. Flecainide toxicity was suspected, and Na bicarbonate infusion was started. Flecainide level was 2.4mcg/mL (normal <1mcg/mL). She went into an idioventricular rhythm which terminated spontaneously (Fig.1C). After 48 hours of Na bicarbonate infusion, lead capture was noted with narrower QRS (198 ms) (Fig.1D) and on day 6, EKG was back to effective BiV pacing with QRS duration 127 ms (Fig.1E). Discussion: This case highlights the EKG manifestations of flecainide toxicity including QRS widening, sine-wave pattern and loss of pacing capture due to prolonged ventricular refractoriness. It also underscores the reversibility of this condition with prompt treatment using Na bicarbonate. Conclusion: Early recognition and rapid treatment of the cardiac effects of flecainide toxicity is critical in managing a life threatening but reversible medical condition.

Abstract 14364: Atrial Fibrillation With Rapid Ventricular Response Induced Ventricular Tachycardia Terminated by Intrinsic Anti-Tachycardia Pacing - A First in Literature Case Report

Background: Intrinsic anti-tachycardia pacing (iATP) is a novel tailored algorithm that has shown increased efficacy against ventricular tachycardia (VT), including fast VT. We describe a case of atrial fibrillation (AF) with rapid ventricular response (RVR) induced VT terminated by iATP. Case description: A 71-year-old male with coronary artery disease, heart failure (EF 30-35%), atrial fibrillation, VT status post biventricular implantable cardioverter defibrillator and failed renal transplant presented with syncope during dialysis. His home medications included amiodarone, metoprolol, apixaban. He was hemodynamically stable on presentation. He had bilateral pitting edema with a systolic murmur and bilateral basilar crackles on exam. His labs were consistent with anemia and end stage renal disease. His device interrogation (Figure) showed AFRVR which degenerated to VT with final cycle length (CL) of 290 msec. First round of ATP with S1x10 burst pulses (88%, CL 250msec) and S2 extra stimuli (CL 230 msec) failed to terminate the VT. Post pacing interval (PPI) was 450 msec. Given calculated remote distance, another five rounds of adaptive iATP with similar S1 pulses but faster S2 and addition of S3 extra stimuli were delivered but were unsuccessful in terminating VT. Finally, the seventh round of iATP (S1x10 at CL 260 msec, S2 at 240 msec) was successful at conversion to sinus rhythm briefly before reverting to AF with controlled ventricular pacing. Discussion: ATP decreases ICD shocks but is programmed empirically and there is less success with fast VT. iATP analyses the PPI of the prior failed sequence to adjust the subsequent ATP therapy by altering the number of burst pulses (S1) and addition of ramp extra stimuli. Computational models and early clinical experience have shown increased efficacy of iATP in terminating fast VT without concomitant increase in VT acceleration. To the best of our knowledge, this is first case report of AFRVR induced VT terminated by iATP.

The Pacemaker and Implantable Cardioverter-Defibrillator Registry of the Italian Association of Arrhythmology and Cardiac Pacing - Report 2022

The Pacemaker (PM) and Implantable Cardioverter-Defibrillator (ICD) Registry of the Italian Association of Arrhythmology and Cardiac Pacing (AIAC) collects information about demographics, clinical characteristics, main indications for PM/ICD therapy and device types from the voluntary Italian collaborating centers. For the year 2022 main data about national PM and ICD implantation activity were obtained on the basis of European Cards and subsequently analyzed to create a standard report. PM Registry: data about 17 800 PM implantations were collected (14 191 first implants and 3609 replacements). The number of collaborating centers was 152. Median age of treated patients was 81 years (75 quartile I; 86 quartile III). Main ECG indications included atrioventricular conduction disorders in 46.0% of first PM implants, sick sinus syndrome in 17.7%, atrial fibrillation plus bradycardia in 7.7%, other unspecified ECG and electrophysiological abnormalities in 43.0%. For first PM implants, pacing in DDDR mode was reported in 42.2%, followed by DDD mode (20.6%), VVIR mode (25.1%), VVI mode (11.1%) and finally VDD-VDDR (5.1%). Median value of longevity of explanted PMs was 8.3 years. ICD Registry: data about 5210 ICD implantations were obtained (3656 first implants and 1554 replacements). The number of collaborating centers was 301. Median age of treated patients was 72 years (63 quartile I; 79 quartile III). Primary prevention indication was reported in 72.4% of first implants, secondary prevention in 27.6% (cardiac arrest in 4.6% of records). A single-chamber ICD was used in 30.3% of first implants, dual-chamber ICD in 30.0% and biventricular ICD in 39.7%. Median value of longevity of explanted ICDs was 7.0 years. In the calendar year 2022, the Italian PM Registry showed stable electrocardiographic and symptom indications, with an important prevalence of dual-chamber pacing. The ICD Registry documented a large use of prophylactic and biventricular ICDs, reflecting a favorable adherence in clinical practice to trials and guidelines. The ICD longevity and the number of recalls demonstrated a favorable trend.

Sacubitril/valsartan effects on arrhythmias and left ventricular remodelling in heart failure: An observational study

AimsConflicting results have been reported in the literature on the potential antiarrhythmic effect of sacubitril/valsartan in heart failure patients with reduced ejection fraction (HFrEF). The objectives of this study were: 1- to evaluate the long term effects of sacubitril/valsartan on arrhythmic burden in HFrEF patients; 2- to evaluate the correlation between the reduction of premature ventricular complexes during f-up and reverse remodelling. MethodsWe identified 255 consecutive HFrEF patients treated with sacubitril/valsartan between March 2017 and May 2020 and followed by the Heart Failure and Cardiac Transplant Unit of IRCCS San Matteo Hospital in Pavia (Italy). Within this subgroup, 153 patients underwent 24 h-Holter-ECG or implantable cardioverter defibrillators (ICD) interrogation at baseline, at 12 months (t1) and at 24 months (t2) and transthoracic echocardiography at baseline and after 12 months after the beginning of sacubitril/valsartan. Cardiac-related hospitalizations were analyzed in the 12 months preceding and during 24 months following the drug starting date. ResultsGlobal burden of 24-h premature ventricular complexes (PVC) was significantly reduced at 12 months (t1) and at 24 months (t2) as compared to the same period before treatment (1043 [304–3360] vs 768 [82–2784] at t1 vs 114 [9–333] at t2, P = 0.000). In the subgroup of patients implanted with biventricular ICD (n = 30), the percentage of biventricular pacing increased significantly (96% [94–99] vs 98% [96–99] at t1 vs 98%[97–100] at t2; P = 0.027). The burden of non-sustained ventricular tachycardia and sustained ventricular tachycardia did not change from baseline to t1 and t2, but a reduction of patients with at least one ICD appropriate shock was reported. The correlations between reduction in 24 h PVC and reduction in LV-ESVi or improvement in LVEF were not statistically significant (respectively R = 0.144, P = 0.197 and R = -0.190, P = 0.074). Heart failure related hospitalizations decreased during follow up (11.1% in the year before treatment vs 4.6% at t1 and 4.6% at t2; P = 0.040). ConclusionSacubitril/valsartan reduced the number of premature ventricular complexes and increased the percentage of biventricular pacing in a cohort of HFrEF patients already on optimal medical therapy. PVC reduction did not correlate with reverse left ventricular remodelling. Whether sacubitril/valsartan has any direct antiarrhythmic effects is an issue to be better explored in future studies.

The Pacemaker and Implantable Cardioverter-Defibrillator Registry of the Italian Association of Arrhythmology and Cardiac Pacing - Report 2021

The Pacemaker (PM) and Implantable Cardioverter-Defibrillator (ICD) Registry of the Italian Association of Arrhythmology and Cardiac Pacing (AIAC) collects information about demographics, clinical characteristics, main indications for PM/ICD therapy and device types from the voluntary Italian collaborating centers. For the year 2021 main data about national PM and ICD implantation activity were obtained on the basis of European Cards and subsequently analyzed to create a standard report. PM Registry: data about 18 631 PM implantations were collected (15879 first implants and 2752 replacements). The number of collaborating centers was 121. Median age of treated patients was 82 years (76 quartile I; 87 quartile III). Main ECG indications included atrioventricular conduction disorders in 26.8% of first PM implants, sick sinus syndrome in 12.2%, atrial fibrillation plus bradycardia in 9.6%, other unspecified ECG and electrophysiological abnormalities in 43.0%. For first PM implants, pacing in DDDR mode was reported in 46.5%, followed by DDD mode (20.6%), VVIR mode (15.0%), VVI mode (9.0%) and finally VDD-VDDR (5.8%). Median value of longevity of explanted PMs was 8.9 years. ICD Registry: data about 6878 ICD implantations were obtained (4708 first implants and 2170 replacements). The number of collaborating centers was 345. Median age of treated patients was 72 years (70 quartile I; 75 quartile III). Primary prevention indication was reported in 86.3% of first implants, secondary prevention in 13.7% (cardiac arrest in 4.4% of records). A single-chamber ICD was used in 32.1% of first implants, dual-chamber ICD in 30.3% and biventricular ICD in 37.6%. Median value of longevity of explanted ICDs was 6.9 years. In the calendar year 2021, the Italian PM Registry showed stable electrocardiographic and symptom indications, with an important prevalence of dual-chamber pacing. The ICD Registry documented a large use of prophylactic and biventricular ICDs, reflecting a favorable adherence in the clinical practice to trials and guidelines. The ICD longevity and the number of recalls demonstrated a favorable trend. In order to increase and optimize the cooperation of Italian PM and ICD implanting centers, the online data entry (https://www.aiac.it/riprid) should be adopted at large scale.

272 A SUDDENLY RIGHT-TO-LEFT SHUNT: THE IMPORTANCE OF EVALUATING PATENT FORAMEN OVALE DURING CARDIOPULMONARY EXERCISE TESTING

Abstract A 55-years-old male affected by heart failure with reduced ejection fraction (HFrEF) was accepted into the Cardiology Department for increasing dyspnea during the last few months. He previously underwent implantation of a biventricular implantable cardioverter defibrillator (ICD) in primary prevention. Medical history included healthy coronary vessels at invasive coronary angiography and an episode of transient ischemic attack (TIA). The patient was referred to our center to evaluate the dyspnea components and to establish an etiology for the novel onset of left ventricular impairment. He underwent a left-right catheterization that did confirm the absence of obstructive coronary disease and signs of pulmonary hypertension (PH) at rest. The transthoracic echocardiogram showed a dilated left ventricle and global hypokinesia (LVEF of 35%). During the stay, the therapy was further optimized according to the latest European guidelines. Before discharge, in order to better assess the dyspnea and the limited tolerance to exercise, a cardiopulmonary exercise testing (CPET) was performed. CPET showed that the VO2 peak was severely reduced compared to the predicted value (16.8 ml/kg/min, corresponding to 51% of the predicted). After 6 minutes of exercise, at around 60 WR, a considerable increase in PETO2 and RER with a concomitant decrease in PETCO2 and a slight oxygen desaturation were observed. Also, a deep increase in VE/VCO2 slope was seen, underlying an exercise-induced pulmonary hypertension. In the suspicion of an inter-atrial shunt, a subsequent rest transthoracic echocardiogram with a bubble test was performed, demonstrating the presence of a patent foramen ovale (PFO). Discussion The foramen ovale is a vestigial communication between the atria that works as a bypass of the pulmonary circulation during fetal life and then seals at birth after the start of breathing in most people. In around 25% of adults, patency of foramen ovale persists and, in some cases, can lead to a source of a right-to-left shunt, particularly in patients with heart failure that can experience PH at rest or during exercise. This may allow a mixture of oxygenated and non-oxygenated blood that affects pulmonary gas exchange efficiency and may allow blood clots formed in the right circulation to embolize into the left circulation. From a pathophysiological point of view, a right-to-left passage of deoxygenated blood induces the activation of chemoreceptors which induce hyperventilation to adequately compensate for the high amount of CO2 in blood from the right sections of the heart. In people not experiencing pulmonary pressure increase during exercise, right-to-left shunt via a PFO is very unlikely since left atrial pressure is higher than right atrial pressure. However, in the presence of PH, right atrial pressure can overcome left atrial pressure and force venous blood through the defect directly into the systemic circulation. The concomitant increase in VE/VCO2 slope underlines exercise-induced PH, which is frequently associated with heart failure and further contributes to exercise intolerance. Conclusions In the presented case, CPET helped diagnose a misunderstood PFO with a right-to-left shunt induced by effort in a patient with a previous TIA. This observation demonstrates that it could be helpful to identify this eventuality during exercise, to discern patients with higher risk of cardiovascular events who would benefit from a percutaneous closure.

Suitability of the left internal jugular vein for CRT-D placement in the setting of extensive venous occlusion: Case report and review of the literature.

Placement of coronary sinus (CS) leads is predominantly accomplished via the left cephalic-axillary-subclavian venous system. However, vein stenosis or occlusion from long-term chronic hemodialysis (HD) in patients with end-stage renal failure can pose a challenge. Cannulation of the CS via the left internal jugular vein (IJV) is technically difficult but often feasible. We report a case in which a patient with end-stage renal disease (ESRD) had extensive left venous system occlusion from prior in dwelling HD catheters, and an AV fistula contralaterally, who underwent biventricular implantable cardioverter defibrillator placement with lead insertion through the left IJV.

Abstract 12732: Cardiac Sarcoidosis With Elevated Cardiac Troponin Mimicking Acute Myocardial Ischemia

Background Cardiac Sarcoidosis (CS) is a disease with variable presentation causing significant morbidity and mortality. Concurrent signs of myocardial injury as evidenced by troponin elevation add to the complexity of an already challenging diagnosis. Case A 48-year-old female with no significant past medical history presented with episodes of presyncope for 2 months. ECG showed a bifascicular block. Troponin I was elevated to 7.29 ng/mL. 2D echo showed Left Ventricular (LV) systolic dysfunction with an LVEF of 40%. Heparin drip was initiated for a possible NSTEMI. Coronary angiography showed no evidence of epicardial coronary artery disease but showed an anomalous right coronary artery which on CT angiogram later showed no hemodynamically significant stenosis. Telemetry monitoring captured intermittent complete atrioventricular blocks. A biventricular implantable cardioverter-defibrillator was inserted. Due to concerns for infiltrative cardiac disease, a cardiac magnetic resonance (CMR) was done showing findings consistent with cardiac sarcoidosis (CS). CT scan of the chest showed radiographic evidence of pulmonary sarcoidosis, however, she declined further invasive workup. She was then started on systemic corticosteroids. 2D echo 6 months later revealed improvement in the LVEF to 55%. Discussion Our case encompasses the variable presentation of CS including cardiac conduction abnormalities and LV systolic dysfunction. Concomitant troponin elevation in CS can mimic myocardial ischemia making the diagnosis more challenging. This highlights the importance of appropriate diagnostic acumen in approaching a case like this. Current guidelines now include non-invasive means for diagnosis including the use of CMR/PET CT, especially since endomyocardial biopsy has a low sensitivity. Treatment strategies aim to mitigate the long-term effects of CS on the heart, however, there is a paucity of data for appropriate pharmacological regimen.

DELAYED LEAD PERFORATION OF THE RIGHT ATRIUM IN THE PRESENCE OF PERSISTENT LEFT SUPERIOR VENA CAVA: A RARE COINCIDENCE

DELAYED LEAD PERFORATION OF THE RIGHT ATRIUM IN THE PRESENCE OF PERSISTENT LEFT SUPERIOR VENA CAVA: A RARE COINCIDENCE

Remote device monitoring shows long-term survival benefit in a propensity matched study of ICD patients

Abstract Funding Acknowledgements Type of funding sources: None. Background Remote monitoring (RM) for implantable cardioverter defibrillators (ICDs) enables early detection of clinical events and reduces inappropriate shocks. However, although RM has been associated with improved clinical outcomes at short to medium-term follow-up, data on long-term survival benefit of RM is currently lacking. Purpose To investigate long-term survival of patients using RM and compare this to a propensity score matched non-RM group. Methods This is a retrospective, observational single-center analysis of patients ≥18 years old implanted with an ICD (single- and dual chamber, biventricular or subcutaneous ICDs) between 1995 and 2021. Data was extracted from the electronic health records. Patients were included in the RM group only if they were started on RM at some point during follow-up. To adjust for differences in baseline characteristics between RM and non-RM patients, propensity score matching was performed in a 1:1 fashion (caliper 0.20) using greedy matching. Estimation of the propensity score was done using logistic regression with RM as the outcome variable, adjusting for 17 covariates (age, gender, year of device implant, type of device, clinical variables and medication at baseline). Time-to-event analysis was performed using Kaplan Meier survival analysis, with significance indicated using a log rank P value. Hazard ratios and 95% confidence intervals (CI) were calculated using a Cox proportional-hazards model. Results A total of 3199 ICD patients were included in this analysis. After propensity score matching for the probability of RM use, 1160 RM patients and 1160 non-RM patients with similar baseline characteristics were selected (mean age 59.1 ±14.8 years, 72.8% male). During a mean follow-up duration of 8.1 ±5.2 years, 363 (31.3%) patients died in the non-RM group and 111 (9.6%) patients died in the RM group (log rank p<0.001, Figure 1). The hazard ratio of RM for mortality was 0.261 (95 CI% 0.211 – 0.323, p=0.001). Conclusion Long-term retrospective analysis indicates a significant survival benefit in ICD patients using RM.

Remote device monitoring for implantable cardioverter defibrillators during the COVID-19 pandemic

Funding AcknowledgementsType of funding sources: None.BackgroundRemote monitoring (RM) for implantable cardioverter defibrillators (ICDs) is recommended as the standard of care in clinical guidelines. Presumably, the restrictions on face-to-face visits that were imposed during the coronavirus (COVID-19) pandemic have further accelerated the adoption of RM. However, quantitative real-world data on the uptake of RM during the COVID-19 pandemic is lacking.PurposeTo assess the uptake of RM during the COVID-19 pandemic to a pre-COVID-19 period, and compare the arrhythmic burden between the two groups.MethodsThis is a substudy of the retrospective, observational single-center DISTANT-study. For this substudy, data from patients who were enrolled in the RM program after de novo ICD implantation (single- and dual chamber, biventricular or subcutaneous ICDs) were analysed. The time until RM was initiated per patient was calculated for patient implanted during the COVID-19 pandemic (March 2020-January 2021) and compared to a similar 10-month period pre-COVID-19 (May 2019-March 2020). ICD therapy (shock and/or anti-tachycardia pacing), non-sustained ventricular tachycardia (NSVT), supraventricular tachycardia (SVT) and mortality were registered for each patient. Patients <18 years old at implantation and patients with a follow-up of <6 months were excluded from this analysis.ResultsA total of 134 patients (72.4 % male, mean age 57.3 ±14.9 years) were eligible for this substudy, of which 61 patients in the COVID-19 group and 73 patients in the pre-COVID-19 group. In both groups there was a similar percentage of primary prevention ICD implantations (COVID-19: 43%, pre-COVID: 44%; p=0.888). During COVID-19, RM was initiated more promptly following ICD implantation compared to pre-COVID-19 (respectively 63 days vs. 131 days; p=0.007). Second, in the COVID-19 group 60.7% patients were enrolled in RM within 30 days following implantation compared to 39.7% in the pre-COVID-19 group (p=0.016). In terms of arrhythmic burden, no differences in the occurrence of ICD therapy (p=0.759), NSVT (p=0.267) and SVT (p=0.454) were observed.ConclusionDuring the COVID-19 pandemic RM was initiated more promptly following ICD implantation compared to before the pandemic, however, no differences in arrhythmic burden between groups were observed.Uptake remote monitoring during COVID-19ICD therapy during 6 months follow-up

PO-672-06 SIMULTANEOUS HIS BUNDLE, LATERAL LV AND LATERAL RV PACING IN A PATIENT WITH REPAIRED TETRALOGY OF FALLOT

Patients with repaired Tetralogy of Fallot (ToF), who have RBBB and predominant right ventricular (RV) dysfunction may benefit from RV electromechanical resynchronization. We describe the case of a patient with repaired ToF, biventricular (BiV) dysfunction and ineffective cardiac resynchronization therapy (CRT) in whom His bundle pacing (HBP) fused with RV wall pacing achieved RV CRT and acute hemodynamic improvement. N/A 58 YOF with repaired ToF and BiV dysfunction presented with decompensated heart failure (HF). BiV implantable cardioverter-defibrillator (ICD) with RA, RV and coronary sinus (CS) leads (Biotronik, Berlin, Germany) was placed at an outside facility one year ago. Underlying EKG showed sinus rhythm with 1stdegree AVB (PR 240 ms), RBBB (QRSd 200ms) and left posterior fascicular block. With presenting CRT, QRS was wider (QRSd 240). Chest Xray revealed RV ICD lead in the right ventricular outflow tract (RVOT) and the CS lead in the anterior interventricular vein with the tip electrode also near RVOT. Given concern for suboptimal CRT, defibrillation vector and limited alternative options, we pursued individualized CRT optimization. Activation mapping showed latest RV activation in the basal lateral tricuspid annulus. Pacing from this site simultaneously with the His Bundle narrowed the QRS significantly and improved RVEF and dyssynchrony on intracardiac echocardiography. Fick cardiac output and index improved to 4.4 and 2.4 respectively from 3.7 and 2.0 at baseline. Thus, we removed the old CS lead and replaced the ICD lead with a new DF-1 defibrillator lead (Medtronic, Minneapolis, MN) in the RV apical septum. Then, we placed a SelectSecureTM His lead (3830 model, Medtronic, Minneapolis, MN). Non-selective His capture threshold was 1.0 V at 0.4 ms. Then, we placed a SelectSecureTM lead (3830 model, Medtronic, Minneapolis, MN) in the RV basal lateral wall and this was Y-adapted to a new LV lead (4196Y model, Medtronic, Minneapolis, MN) which was placed on a lateral branch of the CS. HBP fused with LV and RV lateral wall pacing resulted in a QRS of 120ms. At one year follow up, she has not had HF admissions. Simultaneous HBP and RV basal lateral wall pacing may be a feasible strategy for RV CRT in patients with ToF, RBBB and predominant RV dysfunction.

The Pacemaker and Implantable Cardioverter-Defibrillator Registry of the Italian Association of Arrhythmology and Cardiac Pacing - Report 2020

The Pacemaker (PM) and Implantable Cardioverter-Defibrillator (ICD) Registry of the Italian Association of Arrhythmology and Cardiac Pacing (AIAC) collects information about demographics, clinical characteristics, main indications for PM/ICD therapy and device types from the Italian collaborating centers. For the year 2020, the main data about national PM and ICD implantation activity were obtained on the basis of European Cards and subsequently analyzed to create a standard report. PM Registry: data about 22 080 PM implantations were collected (18 027 first implants and 3803 replacements). The number of collaborating centers was 142. Median age of treated patients was 82 years (75 quartile I; 87 quartile III). ECG indications included atrioventricular conduction disorders in 31.0% of first PM implants, sick sinus syndrome in 13.8%, atrial fibrillation plus bradycardia in 9.9%, other unspecified ECG and electrophysiological abnormalities in 36.6%. Use of single-chamber PMs was reported in 29.0% of first implants, of dual-chamber PMs in 68.2%, of PM with cardiac resynchronization therapy (CRT) in 2.7%. ICD Registry: data about 11 931 ICD implantations were obtained (8266 first implants and 3665 replacements). The number of collaborating centers was 330. Median age of treated patients was 72 years [63 quartile I; 79 quartile III]. Primary prevention indication was reported in 85.0% of first implants, secondary prevention in 15.0% (cardiac arrest in 4.2%). A single-chamber ICD was used in 30.2% of first implants, dual-chamber ICD in 31.2% and biventricular ICD in 38.6%. In the calendar year 2020, the Italian PM Registry showed stable ECG and symptom indications, with an important prevalence of dual-chamber pacing. The ICD Registry documented a large use of prophylactic and biventricular ICDs, reflecting a favorable adherence in clinical practice to trials and guidelines. The ICD longevity and the number of recalls demonstrated a favorable trend. In order to increase and optimize the cooperation of Italian PM and ICD implanting centers, the online data entry (https://www.aiac.it/riprid) should be adopted at large scale.

Comparison of patient and staff temple dose during fluoroscopically guided coronary angiography, implantable cardiac devices, and electrophysiology procedures.

There is a paucity of literature comparing patient and staff dose during coronary angiography (CA), implantable cardiac devices, permanent pacemakers (PPM) and electrophysiology (EP) procedures and little noting dose to staff other than cardiologists. This study sought to compare patient and occupational dose during a range of fluoroscopically guided cardiac procedures. Radiation dose levels for the patients (n=1651), cardiologists (n=24), scrub (n=32) and scout nurses (n=35) were measured in a prospective single-centre study between February 2017 and August 2019. A comparison of dose during CA, device implantation, PPM insertion and EP studies was performed. Three angiographic units were used, with dosimeters worn on the temple of staff. Results indicated that occupational dose during PPM was significantly higher than other procedures. The cardiologist had the highest mean dose during biventricular implantable cardioverter-defibrillators; levels were approximately five times that of 'normal' pacemaker insertions. Transcatheter aortic valve implantations (TAVI) were associated with relatively high mean doses for both staff and patients and had a statistically significant higher (>2 times) mean patient dose area product than all other categories. TAVI workups were also related to higher mean cardiologist and scrub nurse dose. It was observed that the mean scrub nurse dose can exceed that of the cardiologist. The highest mean dose for Scout nurses were recorded during EP studies. Given the significantly higher temple dose associated with PPM insertion, cardiologists should consider utilizing ceiling mounted lead shields, lead glasses and/or skull caps where possible. Efforts should also be made to minimize the use of DSA during TAVI and TAVI workups to reduce cardiologist, nurse and patient dose.

B-PO03-207 THE SHOCKING SECRET BEHIND LEAD NOISE

We present a case of fine ventricular fibrillation (VF) misdiagnosed as right ventricular (RV) lead noise in a patient with left ventricular assist device (LVAD). To demonstrate that fine VF may be misdiagnosed as lead noise. N/A A 66 year old man with non-ischemic cardiomyopathy with Heartmate II LVAD and an Abbott/St Jude biventricular implantable cardioverter-defibrillator (ICD), permanent atrial fibrillation and prior ventricular tachycardia (VT) storm presented with complaints of multiple shocks and was found to be in fine VF. LVAD flow was at 3.2 L/min and pulsatility index (PI) was low at 1.4 indicating lack of myocardial contractility. Amiodarone was initiated and he was transferred to our center. Upon arrival, he remained in VF (Figure 1). Device interrogation revealed VT with appropriate shocks initiating the VF, and that fine VF was labelled as RV lead noise (Figure 1) and therapy withheld. He previously had Secure Sense turned off because of under sensing of VT; due to low amplitude of near field electrogram (EGM), (0.1mV), the device sensed it as RV lead noise. With LVAD support, he remained awake for 7 hours. Due to intolerance of amiodarone or sotalol therapy in the past, lidocaine was added without effect; he was then switched to procainamide drip and was externally cardioverted successfully with 300J. Instantaneously, his mean arterial pressures improved and his LVAD monitor showed a flow of 4.4 L/min and a PI of 2.4. The patient’s device appropriately recognized and shocked his initial VT. However, it has failed to recognize fine VF regardless of appropriate lead function due to low amplitude EGM. LVAD kept him alive for 7 hours.

The Pacemaker and Implantable Cardioverter-Defibrillator Registry of the Italian Association of Arrhythmology and Cardiac Pacing - Annual report 2019

The pacemaker (PM) and implantable cardioverter-defibrillator (ICD) Registry of the Italian Association of Arrhythmology and Cardiac Pacing (AIAC) monitors the main epidemiological data in real-world practice. The survey for the 2019 activity collects information about demographics, clinical characteristics, main indications for PM/ICD therapy and device types from the Italian collaborating centers. The Registry collects prospectively national PM and ICD implantation activity on the basis of European cards. PM Registry: data about 22 889 PM implantations were collected (19 621 first implants and 3268 replacements). The number of collaborating centers was 173. Median age of treated patients was 81 years (75 quartile I; 87 quartile III). ECG indications included atrioventricular conduction disorders in 33.3% of first PM implants, sick sinus syndrome in 16.4%, atrial fibrillation plus bradycardia in 11.6%, other in 38.7%. Among atrioventricular conduction defects, third-degree atrioventricular block was the most common type (18.3% of first implants). Use of single-chamber PMs was reported in 25.5% of first implants, of dual-chamber PMs in 67.1%, of PMs with cardiac resynchronization therapy (CRT) in 1.5%, and of single lead atrial-synchronized ventricular stimulation (VDD/R PMs) in 5.8%. ICD Registry: data about 17 328 ICD implantations were collected (12 129 first implants and 5199 replacements). The number of collaborating centers was 425. Median age of treated patients was 71 years (62 quartile I; 77 quartile III). Primary prevention indication was reported in 83.1% of first implants, secondary prevention in 16.9% (cardiac arrest in 5.9%). A single-chamber ICD was used in 26.1% of first implants, dual-chamber ICD in 28.0% and biventricular ICD in 45.9%. The PM and ICD Registry appears fundamental for monitoring PM and ICD utilization on a large national scale with rigorous examination of demographics and clinical indications. The PM Registry showed stable electrocardiographic and symptom indications, with an important prevalence of dual-chamber pacing. The use of CRT-PM regards a very limited number of patients. The ICD Registry documented a large use of prophylactic and biventricular ICD, reflecting a favorable adherence to trials and guidelines in clinical practice. In order to increase and optimize the cooperation of Italian implanting centers, online data entry (https://www.aiac.it/riprid) should be adopted at large scale.

ATP – A friend with benefits

Anti-tachycardia pacing (ATP) has gained widespread acceptance to treat ventricular tachyarrhythmias and prevent implantable defibrillator shocks. A 63-year-old lady with nonischemic cardiomyopathy underwent insertion of a primary prevention biventricular implantable cardioverter defibrillator (BIV-ICD). Post implant she was found to have recurrent episodes of atrioventricular nodal re-entry tachycardia (AVNRT) based on device electrograms. In this report, we describe the use of anti-tachycardia pacing to manage this tachycardia.

Transient Asystole From Pacing Inhibition During Percutaneous Coronary Intervention

A 68-year-old man with a biventricular implantable cardioverter-defibrillator who was pacemaker dependent was admitted for percutaneous coronary intervention. The patient had an asystolic cardiac arrest as a result of electromagnetic interference during an orbital atherectomy. We should keep electromagnetic interference from the machine in mind when performing orbital atherectomy. (Level of Difficulty: Beginner.)

A hybrid endocardial-epicardial biventricular implantable cardioverter-defibrillator to circumvent the tricuspid valve.

The development of pacing and defibrillator systems that do not involve hardware traversing the tricuspid annulus can be desirable in order to minimize lead-related complications such as tricuspid regurgitation. Occasionally, primary tricuspid valve pathology (ie, infectious endocarditis, nonbacterial thrombotic endocarditis, and carcinoid disease) or congenital heart disease prohibits use of transvenous leads and alternative strategies are required to provide pacing or defibrillation. We describe such a case in which a biventricular implantable cardioverter defibrillator was implanted using a hybrid system involving endocardial and epicardial components.

Reversal of Acute Pacing-induced Cardiomyopathy by Cardiac Resynchronization Therapy in Setting of Post-tavr Heart Block

Introduction Transcatheter aortic valve implantation (TAVR) has emerged as a viable alternative to surgical aortic valve replacement. Due to the anatomical relationship to atrial-ventricular (AV) node and valve implantation site, high grade AV block may happen necessitating pacemaker implantation. Pacing-induced cardiomyopathy may result from sustained, chronic right ventricular (RV) pacing causing electrical dyssynchrony and redistribution of myocardial strain, with subsequent development of left ventricular (LV) systolic dysfunction. Time to onset of heart failure is typically months to years, with rare instances in a matter of days. Case Illustration A 70-year-old woman with a past medical history of severe symptomatic aortic stenosis, pulmonary hypertension, essential hypertension, type 2 diabetes mellitus presented for elective TAVR. Baseline left ventricular ejection fraction (LVEF) was 60-64%. Pre-operative QRS duration was 170 ms (Figure 1a). The procedure was complicated by complete atrial-ventricular block for which a dual chamber pacemaker was implanted emergently. A transthoracic echocardiogram (TTE) performed post-operatively day 1 showed dramatic interval decrease in LVEF from 60-64% to 25-29% with significantly increased end diastolic volume (EDV) and end systolic volume (ESV) suggesting LV dilation (Figure 2). Investigations for potential causes were unrevealing for obvious culprits, including absence of prosthesis dysfunction, unchanged patent coronary anatomy on repeat invasive coronary angiogram. After exclusion of reversible causes, the patient underwent cardiac resynchronization therapy (CRT) with a bi-ventricular implantable cardioverter-defibrillator (ICD) on post-operative day 10. Her symptoms improved and patient was discharged. At one-month follow up, updated TTE showed recovered LVEF of 55-60% with reversal of LV dilation (Figure 2). Electrocardiography (ECG) showed appropriate biventricular pacing (Figure 1b). Device interrogation showed 97% bi-ventricular paced. Conclusion Early recognition of cardiomyopathy induced by pacemaker implantation after TAVR allows prompt appropriate therapy that can reverse the cardiomyopathy process.