Incidence Of Appropriate Therapy Research Articles

Appropriate therapy for implantable cardioverter defibrillators used as primary versus secondary prophylaxis

Abstract Funding Acknowledgements Type of funding sources: None. Background Implantable cardioverter defibrillators (ICD) are used for primary prevention in children highly suspicious of life-threatening arrhythmias due to family history and malignant syncope. This practice might potentially result in a lower incidence of appropriate therapy compared with ICDs implanted for secondary prevention following documented ventricular arrhythmias. Purpose We aimed to compare the rate of appropriate therapy after ICD implantation for primary versus secondary prevention in young children. Method Using national ICD registry, this retrospective nationawide cohort study included children aged ≤15 years who received their first ICD between 1988 and 2020. Patient characteristics, medical history including mortality, device indication, therapy and complications were retrieved from electronic medical files. The primary endpoint was time to appropriate therapy, defined as shock or anti-tachycardia pacing for ventricular tachycardia or fibrillation. Results During the study period, a total of 81 ICDs (39 ICDs pr. million live births) were implanted. Among these, 79 were included in the outcome analysis due to retrievable follow-up data. At baseline, the majority had channelopathies (44%) or structural heart diseases (42%), whereas 25 (32%) and 54 (68%) devices were implanted as primary and secondary prophylaxis, respectively. The median age at primary implantation was 13.9 and 11.6 years (p<0.05), respectively. During a median follow-up of 9.0 (IQR: 4.8–13.9) years, 44 patients experienced appropriate device therapy and 6 died, with no difference for primary and secondary prevention recipients (p=0.34 and p=0.83). The 10-year cumulative incidence of appropriate therapy was 56% for primary prevention recipients and 68% for secondary prevention recipients, whereas 10-year survival probability was 90% (95% CI: 76-100%) and 81 % (95% CI: 63%-99%), respectively. All deaths were of cardiovascular cause. Bleeding occurred in 0 versus 2, infection in 5 versus 4, and inappropriate shock therapy in 2 versus 11 patients, with an overall combined trend towards more events for ICDs implanted as secondary prophylaxis (p=0.08). Conclusions ICD implantation in young children was relatively rare. The rate of appropriate therapy was similar among primary and secondary ICD recipients, indicating too restrictive primary prophylaxis implantation, which should be investigated in future studies. The incidence of complications was highest among secondary ICD recipients.

Outcomes after transvenous defibrillator implantation in cardiac sarcoidosis: A systematic review.

IntroductionSarcoidosis is a systemic inflammatory disorder associated with ventricular arrhythmias (VAs) and sudden death in the context of cardiac involvement. Guidelines advocate implantable cardioverter‐defibrillator (ICD) implantation in specific subcohorts, but there is a paucity of data on outcomes.Methods and ResultsA systematic review was performed to assess outcomes in patients with definite or probable cardiac sarcoidosis (CS) treated with ICD. Observational studies were identified from multiple databases from inception to 21st May 2021. Outcomes of interest included appropriate and inappropriate ICD therapies in addition to all‐cause mortality. Study quality was assessed individually using the Newcastle Ottawa Scale (NOS).Eight studies were identified comprising 530 patients, with follow‐up period of 24–66 months (weighted average 40 months). Mean age was 53.9 years with ejection fraction of 41.3%. Overall incidence of appropriate therapy was 38.1% during follow‐up. Left ventricular systolic dysfunction (LVSD) with ejection fraction <40% was a predictor of appropriate therapy in the majority of studies, as were sustained VAs during electrophysiological testing (EP) in one study. There was no interaction with device indication (i.e. primary or secondary). Where documented, inappropriate therapy was primarily driven by atrial arrhythmias. All‐cause mortality was 6.0% over a median follow‐up period of 42 months. Only three studies achieved good quality in the comparability domain of NOS.ConclusionsAppropriate ICD therapy in patients with CS is commonly associated with LVSD, which can act as a surrogate for scar burden. The utility of EP testing in this setting remains unclear.

A multicentric observational study of patients affected by advanced heart failure with implantable cardioverter defibrillator and left ventricular assist devices

Abstract Funding Acknowledgements Type of funding sources: None. Background Left ventricular assist device (LVAD) implantation is increasingly used in patients with end-stage heart failure. Most patients already have an implantable defibrillator (ICD) at the time of L-VAD implantation. Studies on this patient population are limited by the small sample size and the short duration of follow-up. Purpose The aim of this study was to retrospectively describe the real-world management of patients implanted with both ICD and LVAD. The main objective was to evaluate the incidence and predictors of appropriate and inappropriate therapies of the ICD and the incidence and predictors of ICD related complications. Methods 212 patients were enrolled in four Centers in the period between July 2006 and November 2020. The inclusion criteria were age&amp;gt; 18 years, advanced heart failure, patients with ICD and concomitant or subsequent continuous flow LVAD implantation. ICD therapy was defined as antitachycardia pacing therapy or shock. The data available at the last visit with a median follow up of 21 months were analyzed. Outcome predictors were assessed by univariate logistic regression and the variables of interest included in a multivariate model. Results The rate of appropriate ICD therapies was 29.7%, while the incidence of inappropriate therapies was 10.4%; in the multivariate analysis the presence of a zone therapy with low detection rate (VT zone with median detection rate of 164.5 bpm) was found to be an independent predictor of the composite of appropriate and inappropriate therapies (OR = 19.05; CI = 2.19-165.21; p = 0.007). Interference between ICD and LVAD occurred in 7.5% of cases; the incidence of infectious complications related to the ICD was 7.1% and bleeding complications of 5.2%; in the multivariate analysis, ICD generator replacement was an independent predictor of total complications related to the ICD (interference, infectious and bleeding; OR = 4.45; IC = 1.60-12.36; p = 0.004). 103 patients had CRT defibrillator (48,6%). At follow up there was no statistically significant difference in the incidence of appropriate therapies between those who had CRT-on (n=74) and those who had CRT-off (n=29; p = 0.61). Conclusions Patients with LVAD implanted with an ICD experience a high rate of appropriate and inappropriate ICD therapies. An active VT zone at low heart rate was found to be an independent predictor of ICD therapies. Of more, ICD generator replacement was found to be an independent predictor of total complications related to the ICD. Our findings suggest the importance of tailoring device programming in order to minimize the incidence of ICD therapies, thus sparing the need for generator replacement in this population.

Wearable cardioverter-defibrillator in patients with a transient risk of sudden cardiac death: the WEARIT-France cohort study.

Aims We aimed to provide contemporary real-world data on wearable cardioverter-defibrillator (WCD) use, not only in terms of effectiveness and safety but also compliance and acceptability.Methods and results Across 88 French centres, the WEARIT-France study enrolled retrospectively patients who used the WCD between May 2014 and December 2016, and prospectively all patients equipped for WCD therapy between January 2017 and March 2018. All patients received systematic education session through a standardized programme across France at the time of initiation of WCD therapy and were systematically enrolled in the LifeVest Network remote services. Overall, 1157 patients were included (mean age 60 ± 12 years, 16% women; 46% prospectively): 82.1% with ischaemic cardiomyopathy, 10.3% after implantable cardioverter-defibrillator explant, and 7.6% before heart transplantation. Median WCD usage period was 62 (37–97) days. Median daily wear time of WCD was 23.4 (22.2–23.8) h. In multivariate analysis, younger age was associated with lower compliance [adjusted odds ratio (OR) 0.97, 95% confidence interval (CI) 0.95–0.99, P < 0.01]. A total of 18 participants (1.6%) received at least one appropriate shock, giving an incidence of appropriate therapy of 7.2 per 100 patient-years. Patient-response button allowed the shock to be aborted in 35.7% of well-tolerated sustained ventricular arrhythmias and in 95.4% of inappropriate ventricular arrhythmia detection, finally resulting in an inappropriate therapy in eight patients (0.7%).ConclusionOur real-life findings reinforce previous studies on the efficacy and safety of the WCD in the setting of transient high-risk group in selected patients. Moreover, they emphasize the fact that when prescribed appropriately, in concert with adequate patient education and dedicated follow-up using specific remote monitoring system, compliance with WCD is high and the device well-tolerated by the patient.

Abstract 16519: Meta-analysis of Outcome After Implantable Cardioverter Defibrillator Therapy in Patients With Cardiac Amyloidosis

Introduction: Cardiac amyloidosis is associated with high risk for sudden cardiac death. However, the potential benefit of implantable cardioverter defibrillator (ICD) implantation in CA is unknown due to limited available data regarding outcomes following ICD implantation in this patient population. We sought to perform a meta-analysis of trials that evaluated the outcomes of ICD implantation in CA. Methods: We performed a systematic literature review in PubMed, SCOPUS, and Cochrane to identify all studies that evaluated ICD therapy in CA until May 2020. Outcomes analyzed were all-cause mortality and appropriate ICD therapy rates. A random effects model was used to calculate percentages and 95% confidence intervals (CI) of outcomes. Results: Of the screened articles, 5 observational studies were included for analysis. A total of 151 patients were analyzed. Mean age of population was 61.6 +/- 0.7 years and 79.2% were male. The all-cause mortality rate was 33% (95% CI:16 to 51%) and the incidence of appropriate ICD therapy was 23% (95% CI:16 to 30%) over a mean follow up period of 16 months (Figure). In trials that evaluated ICD therapy in non-ischemic cardiomyopathy such as DANISH, DEFINITE and SCD-HeFT trials mortality rates in the ICD arm were 21.6 % over 67.6 months, 9.4% over 29 months and 16.7% over 45.5 months, respectively. The incidence of appropriate therapy in DANISH, DEFINITE and SCD-HeFT trials were 28.9%, 19.8 % and 21% respectively. Conclusions: CA patients with ICD have equivalent appropriate therapy with disproportionately higher mortality over a shorter follow up compared to randomized trials of primary prevention ICD placement in NICMP. The benefit of ICD placement for mortality reduction in CA remains unclear and further large-scale studies are required to address this issue.

Relationship between episodes of unsustained VTs detected early after an ICD implant and subsequent monomorphic VTs causing appropriate therapy

Abstract Introduction Non-sustained ventricular tachycardias (NSVT) are observed frequently among ICD patients with left ventricular dysfunction (LVD). Purpose To analyze the relationship between episodes of NSVTs and monomorphic VTs (MVTs) that subsequently cause appropriate therapies. Methods 416 ICD patients with LVD (LVEF &amp;lt;45%) followed for 41±27 months. ICD programming (detection and therapies) was standardized. NSVT was defined as any VT of ≥5 beats which did not met the detection criteria occurring within the first 6 months after ICD implant. We analyzed 2201 NSVTs (10+7 beats), which occurred in 250 of the 416 patients (Median=2; IQR=0–7). The mean cycle length (CL) of NSVT was 323±32 ms (adjusted per multiple episodes/patient, generalized estimating equation method (GEEM)). Results During the follow-up, 1441 MVT occurred in 183 patients. After showing a significant correlation between burden of NSVT and the occurrence of appropriate therapies due to MVT (C coefficient=0.68; p&amp;lt;0.001), we observed that subjects with &amp;gt;5 NSVT presented an excess of adjusted risk: HR=1.97 (95% CI=1.45–2.72); p&amp;lt;0.001. However, the adjusted mean CL of NSVTs was similar in patients with (322±34) vs. without MVT (324±26 ms); p=0.3. Among patients who presented NSVTs and MVTs (n=145 subjects), we analyzed the relationship between the adjusted mean CL of the NSVTs (n=1288 episodes) and the CL of the first appropriate therapy due to MVT occurring subsequently. We found a significant and positive correlation between the two (r=0.88; p&amp;lt;0.001); the strongest correlation was observed in subjects with &amp;gt;5 NSVTs (r=0.97, n=52)). The robustness of such correlation was similar in individuals with ischemic (r=0.86; n=91) versus non-ischemic cardiomyopathy (r=0.90; n=54), and in primary (r=0.86; n=75) versus secondary prevention (r=0.90; n=70). The agreement between the CL of first MVT and the adjusted mean CL of NSVT episodes (GEEM) was determined according to the Bland-Altman Method. The difference between the two values was 2±8.3 ms, with only 7.6% (11/145) of patients in whom the difference between the two CL was outside the concordance limits. The agreement was greater, again, in individuals with &amp;gt;5 NSVTs. As shown in the Figure, in more than 95% of patients both values were within the interval of agreement (0.32±4 ms). Conclusions 1-The burden of NSVTs occurring early after an ICD implant, but not their CL, is associated with a higher incidence of appropriate therapies due to MVT at follow-up. 2-The CL of the NSVTs and that of the first and subsequent MVTs is virtually the same in patients with higher NSVT burden. Therefore, it could be the same tachycardia, but with different duration. Figure 1 Funding Acknowledgement Type of funding source: None

P523Incidence of anti tachycardia therapies and mortality at one and two years in patients with and without persistent ICD indication at the time of generator replacement

Abstract BACKGROUND ICD implantation with or without resynchronization is an established therapy for the prevention of sudden cardiac death in patients with LV dysfunction. However, when elective replacement interval (ERI) approaches most patients undergo generator replacement (GR) even in the absence of persistent indication to ICD therapy- Moreover, at the time of GR patients are usually older and with more comorbidities as compared to the time of first implantation. AIM The aim of our work was to evaluate the rate and predictors of mortality and to analyze.the incidence of appropriate ICD therapies after GR. METHODS Our registry includes 323 patients with structural heart disease (SHD) implanted with ICD in primary prevention who underwent GR. Our population was stratified based on the presence or absence of persistent indication to ICD at the time of GR, which was defined as: LVEF ≤ 35% and/o history of appropriate ICD therapies during the first generator"s life. In each group the incidence of appropriate ICD therapies after GR, 1 and 2 years mortality after GR and multivariate predictors of 1 year mortality. Were analyzed. Comparisons between categorical variables were made using χ2 or Fisher Exact test when required and continuous variables were compared using Mann Whitney test. Kaplan-Meier curves with Log Rank test were used to investigate 1 and 2 years mortality. RESULTS In our population, 81% were male, 41% had ischemic heart disease, 60% had CRT-D. Median LVEF at the time of first implantation was 30% (25-35), whereas at the time of GR was 35% (25-45); median age at GR was 64 (56-73) years. Notably 33.6% of our population no longer met ICD indication at the time of GR; this subgroup showed a significantly lower mortality at one and two years as compared to patients with persistent ICD indication: 1% vs 9% and 2.1% vs 13.5% respectively (figure 1 and 2). At multivariable analysis permanent AF (HR: 3.6; 95% CI 1.9-8.6) chronic renal disease (HR 4; 2.3-8.9), and persistent ICD indication were independent predictors of 1-year mortality. When survival analysis was limited to patients implanted with single-chamber and dual-chamber devices only AF an renal insufficiency remained significantly predictors of mortality. Nevertheless, in this subgroup, the absence of persistent indication was associated with a significantly lower rate of appropriate ICD therapies after GR (0% vs 14.8%, p = 0.02). CONCLUSION The absence of persistent indication at the time of generator replacement was associated with a significantly better prognosis and a lower incidence of appropriate therapies after GR. Atrial fibrillation, renal insufficiency and persistent ICD indication significantly predicted 1 year mortality in our population. Our data suggest the importance of an arrhythmic vs. non-arrhythmic risk evaluation in the individual patient at the time of ICD generator replacement Abstract Figure.

A050 Defibrillator Therapy in Patients Receiving a Primary Prevention CRT-D Device: The Wellington Experience

There is no clear consensus on whether to routinely insert a primary prevention defibrillator in patients receiving CRT. Improvement of cardiac status may reduce the likelihood of ventricular arrhythmia and therefore the need for an ICD. This is especially true in patients with a non-ischaemic cardiomyopathy. The risk of inappropriate therapy must also be taken into account. Our aim was to review the incidence of appropriate and inappropriate therapy in patients undergoing CRT-D implantation under active follow up. Patients with an active CRT-D were sampled from the PaceArt database. Those who received a primary prevention device were included in the analysis. Baseline data and therapy received was collected. There were 78 patients in our analysis. 11(14%) had an ischaemic cardiomyopathy, 64 (82%) had a non-ischemic cardiomyopathy and 3(4%) were of mixed aetiology. The average age at implant was 63 years. 27(35%) were female. The mean EF at implant was 23%. In total, 19 (24%) patients received therapy. 4(5%) received inappropriate therapy, 1 received an inappropriate shock. 45% of ischaemic cardiomyopathy patients received therapy vs 22% of non-ischaemic patients. There were no cases of inappropriate therapy in ischaemic patients. The incidence of appropriate therapy is higher with ischaemic cardiomyopathy than with non-ischaemic cardiomyopathy for patients in our data set. The number of patients receiving inappropriate therapy was low. This may help with device selection and inform patients of potential risks and benefits.

2404The use of wearable cardioverter defibrillator in France

Abstract Background The wearable cardioverter defibrillator (WCD) has been shown to be useful during transient periods of high sudden cardiac death risk, and the issue of compliance recently pointed out. This Registry was designed to provide real-world data on WCD use in France, in terms of compliance, potential adverse events, as well as efficacy. Methods and results Multicenter evaluation (WEARIT FRANCE Registry) was conducted in France between January 2017 and March 2018. Overall, 1,157 patients were analyzed: 950 with ischemic heart disease (82%, including 647 patients after myocardial infarction), 119 after ICD explant (10%), and 88 pre-transplant (8%). The median age was 61 years; the median ejection fraction was 25%. Median WCD wear time was 62 days, with median daily use of 23.4 hours. Less than 1% of patients did not wear WCD at least 4 hours per day. During follow-up, a total of 42 sustained ventricular tachyarrhythmias (VT/VF) occurred in 36 patients, of whom 50% (n=18) received appropriate WCD shocks, giving an incidence of appropriate therapy of 1.56%. The rate of all VT/VF episodes were 3.1% among patients with ischemic cardiomyopathy (n=29/950) versus 3.4% for the others (n=7/207). Of the ischemic patients wearing beyond 30 days (N=784), 5 received appropriate therapy of VT/VF episodes. Overall shock survival was 100%. At the end of the WCD period, 586 patients (51%) were implanted with an implantable cardioverter defibrillator. Eight patients (0.69%) received inappropriate WCD shocks. Regarding the apparent very low proportion of women considered for WCD therapy, we aimed to appreciate in which extent Conclusions In this multicenter nationwide WCD evaluation, 3.1% of patients presented with sustained VT/VF with 47% of those patients developing VT/VF after 30 days. The incidence of inappropriate therapy was low. The compliance to WCD in this real life evaluation was very high. These data suggest that the WCD, when worn appropriately, may be helpful in the arsenal to protect high-risk patients against SCD, especially in case of transient risk situations. Acknowledgement/Funding Zoll

Incidence of appropriate implantable cardioverter-defibrillator therapy and mortality after implantable cardioverter-defibrillator generator replacement: results from a real-world nationwide cohort.

The safety of omitting implantable cardioverter-defibrillator (ICD) generator replacement in patients with no prior appropriate therapy, comorbid conditions, and advanced age is unclear. The aim was to investigate incidence of appropriate ICD therapy after generator replacement. We identified patients implanted with a primary prevention ICD (n = 4630) from 2007 to 2016, who subsequently underwent an elective ICD generator replacement (n = 670) from the Danish Pacemaker and ICD Register. The data were linked to other databases and evaluated the outcomes of appropriate therapy and death. Predictors of ICD therapy were identified using multivariate Cox regression analyses. A total of 670 patients underwent elective ICD generator replacement. Of these, 197 (29.4%) patients had experienced appropriate therapy in their 1st generator period. During follow-up of 2.0 ± 1.6 years, 95 (14.2%) patients experienced appropriate therapy. Predictors of appropriate therapy in 2nd generator period was low initial left ventricular ejection fraction (≤25%) [hazard ratio (HR) 1.87, confidence interval (CI) 1.13-1.95] and appropriate therapy in 1st generator period (HR 3.95, CI 2.57-6.06). For patients with appropriate therapy in 1st generator period, 4-year incidence of appropriate therapy was 50.6% vs. 16.4% in those without (P < 0.001). Among patients >80 years with no prior appropriate therapy 8.8% of patients experienced appropriate therapy after replacement. Comorbidity burden and advanced age were associated with reduced device utilization after replacement and a high competing risk of death without preceding appropriate therapy. A significant residual risk of appropriate therapy in the 2nd generator was present even among patients with advanced age and with a full prior generator period without any appropriate ICD events.

Incidence of appropriate anti-tachycardia therapies after elective generator replacement in patient with heart failure initially implanted with a defibrillator for primary prevention: Results of a meta-analysis

BackgroundImplantable cardioverter-defibrillator (ICD) is an effective therapy to reduce mortality in heart failure. When the ICD generator approaches the end of life, most of the patients undergo an elective generator replacement (GR) even if they no longer meet implantation criteria. Whether arrhythmic risk should be re-assessed at the time of GR is still an open question. The aim of our study was to assess, via a meta-analysis, the occurrence of appropriate ICD therapies after GR in patients stratified based on the presence/absence of ICD indication at the time of GR. MethodsVia a systematic literature search for primary prevention studies (January 2000-Sectember 2018), 2976 studies were analyzed. 6 studies were lastly included. Patients were categorized into two groups: “with ICD indication” in case of LVEF≤35% at the time of GR and/or appropriate therapies during the first ICD life; “without ICD indication” in case of a LVEF>35% and no previous ICD therapies. Incidences of appropriate ICD therapies were computed as number of events per 100 person-year. ResultWe included 478 pts. (65%) with and 255 patients (35%) without persistent ICD indication. The incidence of appropriate therapies was 12.3/100-person-year in patients with vs. 3.4 in patients without persistent ICD indication (2.98 fold higher risk of ICD therapies). ConclusionPatients who no longer meet ICD implantation criteria at the time of GR present a significantly lower risk of appropriate ICD therapies after GR. The results of this study underline the importance of an arrhythmic risk re-stratification at the time of GR.

Abstract 16709: Multicenter Assessment of Wearable Cardioverter Defibrillator Use in Patients at Risk of Sudden Cardiac Death: France National Experience

Hypothesis: The wearable cardioverter defibrillator (WCD) has been shown to be useful during transient periods of high sudden cardiac death risk. This Registry was designed to provide real-world data on WCD use in France, in terms of compliance, potential adverse events, as well as efficacy. Methods: Multicenter evaluation (WEARIT FRANCE Registry) was conducted in France between January 2017 and March 2018. Overall, 1013 patients with complete data sets were analyzed: 834 with ischemic heart disease (82%, including 577 patients after myocardial infarction), 111 after ICD explant (11%), and 68 pre-transplant (7%). The median age was 61 years; the median ejection fraction was 25.4%. Results: Median WCD wear time was 61 days, with median daily use of 23.4 hours. Less than 1% of patients did not wear WCD at least 4 hours per day. During follow-up, a total of 35 sustained ventricular tachyarrhythmias (VT/VF) occurred in 30 patients, of whom 56.7% (n=17) received appropriate WCD shocks, giving an incidence of appropriate therapy of 1.7% . The rate of all VT/VF episodes were 2.9% among patients with ischemic cardiomyopathy (n=24/834) versus 3.3% for the others (n=6/179). Of the ischemic patients wearing beyond 30 days (N=657), 7 received appropriate therapy. Overall shock survival was 100%. Supra-ventricular tachycardia occurred in 6 patients. At the end of the WCD period, 564 patients (55.7%) were implanted with an implantable cardioverter defibrillator. Among the patients who had an ejection fraction below 35% at baseline, and were not implanted with an implantable cardioverter defibrillator (N=416), 351 (82%) had an improvement in ejection fraction to &gt;35%. Five patients (0.49%) received inappropriate WCD shocks. Conclusions: In this multicenter nationwide WCD evaluation, 3% of patients presented with sustained VT/VF with 40% of those patients developing VT/VF after 30 days. The incidence of inappropriate therapy was low. These data suggest that the WCD, when worn appropriately, may be helpful in the arsenal to protect high-risk patients against SCD, especially in case of transient risk situations.

Temporal Trends Over a Decade of Defibrillator Therapy for Primary Prevention in Community Practice.

Technology and clinical practice surrounding the use of the primary prevention implantable cardioverter defibrillator (ICD) are in a state of constant evolution. The purpose of the study was to test the hypothesis of significant temporal trends in characteristics and outcomes over a decade of ICD therapy. Between 2002 and 2012, 5,539 consecutive patients (age 62.5 ± 11 years, 84.9% male), with ischemic or nonischemic cardiomyopathy, implanted with a primary prevention ICD from 12 centers in France were included. Information on characteristics and outcomes (including causes of death) were evaluated over a median follow-up of 994 days (466-1,667). In addition to a shift in the type of devices implanted with a significant increase in cardiac resynchronization therapy-defibrillator (CRT-D) over time (43.6 to 60.4%, P = 0.0001), an increase in mean age (from 61.5 ± 11.6 to 63.2 ± 10.9 years, P = 0.0016), proportion of nonischemic cardiomyopathy (31.0 to 44.7%, P <0.0001) and women recipients (11.4 to 15.8%, P = 0.004) was observed. A total of 1,181 patients (22.3%) received ≥1 appropriate therapy, inappropriate therapies occurred in 355 patients (6.7%) and 826 patients (15.2%) died, mainly from cardiovascular causes (49.3%). Annual mortality incidence (5.4% to 4.3%, P = 0.05), as well as incidence of appropriate therapy (10.4% to 7.1%, P = 0.0004), significantly decreased over the decade. By contrast, incidence of ICD-related late (>30 days after implant) complications significantly increased (4.6 to 7.6%, P = 0.003). Our findings demonstrate significant changes in patterns of use and outcomes in primary prevention ICD over the last decade with reductions in mortality and appropriate therapies, counterbalanced by an increase in complications.

Performance of the subcutaneous implantable cardioverter-defibrillator in patients with a primary prevention indication with and without a reduced ejection fraction versus patients with a secondary prevention indication

The subcutaneous implantable defibrillator (S-ICD) provides an alternative to the transvenous ICD for the prevention of sudden cardiac death, but has not been well studied in the most commonly treated transvenous ICD patient population, namely, primary prevention (PP) patients with left ventricular dysfunction. The analyses in the present study were designed to compare clinical outcomes for PP patients with and without a reduced ejection fraction (EF) and secondary prevention (SP) patients implanted with the S-ICD. All patients 18 years and older from the S-ICD IDE study and the EFFORTLESS Registry with available data as of November 18, 2013, were included (n = 856; mean follow-up duration 644 days). Outcomes were evaluated in 2 analyses: (1) comparing all PP patients (n = 603, 70.4%) with all SP patients (n = 253, 29.6%) and (2) comparing all PP patients with an EF ≤35% (n = 379) with those with an EF >35% (n = 149, 17.4%). No differences were observed in mortality, complications, inappropriate therapy, or ability to convert ventricular tachyarrhythmias between SP and PP patients. However, SP patients had a higher incidence of appropriate therapy than did PP patients (11.9% vs 5.0%; P = .0004). In the PP subanalysis, the cohort with an EF ≤35% had significantly older patients with more comorbidities and higher mortality (3.0% annually vs 0.0%). Despite these differences, device-related complications, conversion efficacy, and incidence of inappropriate shock therapies were not significantly different between PP subgroups. The S-ICD performs well in protecting patients with either PP or SP implant indications from sudden cardiac death. Within PP patients, device performance was independent of EF.

Temporal trends and long term follow-up of implantable cardioverter defibrillator therapy for secondary prevention: A 15-year single-centre experience

BackgroundThe aim of this study was to determine overall and aetiology-related incidence of secondary prevention ICD implantation over the last 15years in Canton Ticino and to assess clinical outcome according to time period of implantation. Methods and resultsConsecutive patients treated by implantation of an ICD for secondary prevention from 2000 to 2015 were included in the current study and compared between 5-year cohorts (2000/2004; 2005/2009; 2010/2015). Yearly implantation rate, changing in clinical presentation over years and events during follow-up were evaluated. One-hundred fifty six patients were included. ICD implantation rate increased from 2.1 in 2000–2005 to 5.1 in 2010–2015, respectively (p 0.001). There was an increase in the proportion of non-ischaemic patients and of ventricular tachycardia (VT) as presenting rhythm. No differences in appropriate ICD interventions were observed according to aetiology, presenting arrhythmia or type of device. Reverse remodelling was observed more often in non-ischaemic patients, without any influence on the occurrence of appropriate interventions. Previous myocardial infarction (MI), atrial fibrillation (AF), NYHA class 2–3 and left ventricular ejection fraction (LVEF)<35% were predictors of appropriate therapies during follow-up. ConclusionsRate of implants for secondary prevention indication has almost doubled during the last 15years. Importantly, there has been a progressive increase of non-ischaemic patients receiving an ICD, and of VT as presenting rhythm. Patients had an overall good survival and a relatively low incidence of appropriate therapies. Improvement of ejection fraction did not correlate with risk reduction of ventricular arrhythmias.

Outcome of Primary Prevention Implantable Cardioverter Defibrillator Therapy According to New York Heart Association Functional Classification

We aimed to assess if the outcome of primary prevention implantable cardioverter defibrillators (ICDs) without cardiac resynchronization therapy is dependent on New York Heart Association (NYHA) class. Among the participants of Défibrillateur Automatique Implantable-Prévention Primaire (DAI-PP; NCT01992458) multicenter cohort study, 155patients in NYHA class I, 504 in NYHA class II, and 188 in NYHA class III had a QRSwidth <120ms and were implanted with an ICD without cardiac resynchronization therapy and, thus, were eligible for the purpose of this analysis. Total and specific mortalities and the incidence of appropriate therapies were assessed for every NYHA. During 2,606 patient-years (3.1 ± 2.1years), 104 (12.3%) subjects died and 188 (22.2%) experienced appropriate therapies. After adjustment, overall mortality increased with NYHA class (adjusted hazard ratio [HR] 1.63, 95% confidence interval [CI] 1.11 to 2.41, p= 0.014), driven by an increase in cardiovascular death. Conversely, incidence of appropriate ICDintervention was comparable among the 3 NYHA groups (NYHA class I 7.43, NYHA class II 7.91, and NYHA class III 12.10 per 100 patient-years; HR 1.19, 95% CI 0.89 to 1.59, p= 0.231). Incidence of ICD-unresponsive sudden death was very low and also comparable (NYHA class I 0.22, NYHA class II 0.36, and NYHA class III 0.83 per 100 patient-years (HR 6.34, 95% CI 0.32 to 124.49, p= 0.224). No significant differences were observed in the other specific modes of death. In conclusion, although patients in NYHA class III have higher overall mortality, they experience a comparable incidence of appropriate ICD therapies. The low incidence of ICD-unresponsive sudden death in all assessed NYHA classes also supports the efficacy of ICDs, irrespective of NYHA class.

Increasing age does not affect time to appropriate therapy in primary prevention ICD/CRT-D: a competing risks analysis.

To evaluate the impact of age on the clinical outcomes in a primary prevention implantable cardioverter defibrillator (ICD)/cardiac resynchronization therapy defibrillator (CRT-D) population. A retrospective, multicentre analysis of patients aged 60 years and over with primary prevention ICD/CRT-D devices implanted between 1 January 2006 and 1 November 2014 was performed. Survival to follow-up with no therapy (T1), death prior to follow-up with no therapy (T2), delivery of appropriate therapy with survival to follow-up (T3), and delivery of appropriate therapy with death prior to follow-up (T4) were measured. In total, 424 patients were eligible for inclusion in the analysis, mean follow-up of 32.6 months during which time 44 patients (10.1%) received appropriate therapy. The sub-hazard ratio (SHR) for the cumulative incidence of appropriate therapy (T3) according to age at implant was 1.00 (P = 0.851; 95% CI 0.96–1.04). The SHR for cumulative incidence of death (T2) according to age at implant was 1.06 (P < 0.001; 95% CI 1.03–1.01). Age at implant, ischaemic aetiology, baseline haemoglobin, and the presence of diabetes mellitus were predictors of all-cause mortality. Age has no impact on the time to appropriate therapy, but risk of death prior to therapy increases by 6% for every year increment. As the ICD population ages, the proportion who die without receiving appropriate therapy increases due to competing risks. Characterizing competing risks predictive of death independent of ICD indication would focus therapy on those with potential to benefit and reduce unnecessary exposure to ICD-related morbidity.

Abstract 11447: Low Incidence of Appropriate Therapy Following Defibrillator Implantation for Primary Prevention of Sudden Cardiac Death in Hypertrophic Cardiomyopathy

Introduction: Hypertrophic cardiomyopathy (HCM) is a leading cause of sudden cardiac death (SCD) in young adults. Implantable cardioverter defibrillators (ICD) effectively terminate ventricular tachycardia (VT) and fibrillation (VF) that cause SCD, but the reported prevalence of and patient characteristics leading to appropriate ICD therapy in HCM have been variable. Hypothesis: We hypothesized that some risk factors may be more prevalent than others in patients with HCM who receive appropriate ICD therapy and that the overall incidence of appropriate therapy may be lower than that reported previously. Methods: We retrospectively studied all patients with HCM who were treated with ICDs at our referral center from 2000-2013 to determine the rates of appropriate and inappropriate ICD therapies. Results: Of 1136 patients with HCM, we identified 135 who underwent ICD implantation (125 for primary and 10 for secondary prevention), aged 18-81 years (mean 48±17) at the time of implantation. The mean follow-up time was 5.2±4.5 years. Appropriate ICD intervention occurred in 20 of 135 patients (2.8%/year) by providing a shock or antitachycardia pacing in response to VT or VF. The annual rate of appropriate ICD therapy was 2.4%/year for primary and 7.2%/year for secondary prevention devices. Commonly used risk factors were equally prevalent among patients who received appropriate therapy and those who did not; furthermore, the likelihood of receiving appropriate therapy in the presence of each risk factor was similar (Figure). Inappropriate ICD therapy occurred in 27 patients (3.8%/year). Conclusions: ICDs provide clear benefit to patients who experience life-threatening arrhythmias, particularly those being treated for secondary prevention. However, the appropriate therapy rate for primary prevention was lower than previously reported, and no single risk factor appeared to have stronger association with appropriate ICD therapy than others.

Abstract 12432: Temporal Trends over a Decade of Defibrillator Therapy for Primary Prevention in Community Practice

Aims: Technology and clinical practice surrounding the use of the primary prevention implantable cardioverter defibrillator (ICD) are in a state of constant evolution. Using a multicenter national registry, we evaluated temporal trends in characteristics and outcomes over a decade of ICD therapy. Methods and Results: Between 2002-2012, 5,539 consecutive patients (age 62.5±11 years, 84.9% male, 60.2% with coronary artery disease) implanted with a primary prevention ICD from 12 centers in France were enrolled. Information on characteristics and outcomes (including causes of death) were evaluated over a median follow-up of 994 days [466-1,667]. In addition to a shift in the type of devices implanted with a significant increase in cardiac resynchronization therapy-defibrillator (CRT-D) over time (43.6 to 60.4%, P=0.0001), an increase in mean age (from 61.5±11.6 to 63.2±10.9 years, P=0.0016), proportion of non-ischemic cardiomyopathy (31.0 to 44.7%, P&lt;0.0001) and women recipients (11.4 to 15.8%, P=0.004) was observed. A total of 1,181 patients (22.3%) received ≥1 appropriate therapy, inappropriate therapies occurred in 355 patients (6.7%) and 826 patients (15.2%) died mainly from cardiovascular cause (407 patients corresponding to 49.3%). Annual mortality incidence (5.4 to 4.3%, P=0.05) and annual incidence of appropriate therapy (10.4 to 7.1%, P=0.0004, Figure) significantly decreased over the decade. By contrast, incidences of ICD-related complications increased over the decade (4.6 to 7.6%, P=0.003). Conclusion: Our findings demonstrate significant changes in patterns of use and outcomes in primary prevention ICD over the last decade with reductions in mortality, appropriate therapies, associated with an increase in complications.

Abstract 12621: Gender Differences Among Implantable Cardioverter Defibrillators Recipients in the Setting of Primary Prevention

Background: Data regarding sex specificities in the use, benefits and complications of implantable cardioverter-defibrillators (ICDs) in primary prevention in the real-world European setting are sparse. Methods: Using a large multicentric cohort of consecutive patients referred for ICD implantation for primary prevention (2002-2012), in the setting of coronary artery disease or dilated cardiomyopathy, we examined potential sex differences in subjects’ characteristics and outcomes. Results: Of 5,539 patients, only 837 (15.1%) were women and 53.8% received cardiac resynchronization therapy (CRT-D). Compared to men, women presented a significantly higher proportion of dilated cardiomyopathy (60.2% vs. 36.2%, P120ms: 74.6% vs. 68.5%, P=0.003), higher New York Heart Association functional class (2.5±0.7 vs. 2.4±0.7, P=0.003) and lower prevalence of atrial fibrillation (18.7% vs. 24.9%, P&lt;0.001). During a 16,786 patient-years follow-up, overall, fewer appropriate therapies were observed in women (HR = 0.59, CI95% 0.45-0.76; P&lt;0.001). By contrast, no sex-specific interaction was observed for inappropriate shocks (OR for women = 1.00, 95%CI 0.74-1.35, P=0.997) and mortality (HR = 0.87; 95%CI 0.66-1.15, P=0.324), with similar patterns of cause of deaths. Conclusion: In our real life registry, women account for the minority of ICD recipients. While female ICD recipients present with features of more severe heart failure in the setting of primary prevention of sudden cardiac death, we observed they have a 40% lower incidence of appropriate therapies.