Cardiac Resynchronization Therapy Defibrillator Research Articles

Cardiac Strains As a Tool for Optimization of Cardiac Resynchronization Therapy in Non-responders: a Pilot Study.

BackgroundApproximately 30% of patients do not respond to implantation of Cardiac Resynchronization Therapy – Defibrillators (CRT-D). The aim of this study was to investigate the potential for cardiac strain speckle tracking to optimize the performance of CRT-D in non-responding patients.Methods30 patients not responding to Cardiac Resynchronization Therapy-Defibrillators after 3 months were randomly divided into control and intervention groups. Atrioventricular interval was adjusted so that E and A waves did not overlap, the interventricular interval was subsequently optimized to yield maximum improvement of the sum of longitudinal+radial+circumferential strains. The left ventricular ejection fraction (LVEF) and NYHA improvement 3 months after optimization were evaluated and use of other strain combinations assessed.ResultsA significant correlation between the (combined) strain change and LVEF improvement was detected (p<0.01). 75% of patients with non-ischemic etiology of heart failure who did not respond to the original CRT-D reacted favorably with significant LVEF and NYHA improvement. The area strain was the best predictor of LVEF/NYHA improvement in those patients. No significant improvement was recorded in patients with ischemic etiology.ConclusionsAV and VV optimization based on speckle tracking is a very promising method potentially leading to a significant improvement of the outcome of CRT-D, especially in patients with non-ischemic etiology of heart failure.

Contemporary epidemiology and treatment of hospitalized heart failure patients in real clinical practice in China

Objective: To observe the etiology, comorbidities, clinical features and treatment patterns of hospitalized patients with heart failure (HF) in China. Methods: Data were collected prospectively on hospitalized patients with HF who were enrolled in China Heart Failure Center Registry Study from 169 participating hospitals from January 2017 to August 2018. In this cross-sectional study, patients were stratified by left ventricular ejection fraction (LVEF) category: heart failure with reduced ejection fraction (HFrEF, LVEF<40%); heart failure with mid-ranged ejection fraction (HFmrEF, 40%≤LVEF<50%) and heart failure with preserved ejection fraction (HFpEF, LVEF≥50%). The clinical data were collected, including demographic information, diagnosis, signs, electrocardiogram, echocardiography, laboratory tests, and treatment. Results: A total of 31 356 hospitalized patients with HF were included, 19 072 (60.8%) were males and the average age was (67.9±13.6) years old. The common causes of HF were hypertension (57.2%), coronary heart disease (54.6%), dilated cardiomyopathy (14.7%), valvular heart disease (9.2%). The common complications were atrial fibrillation/atrial flutter (34.1%), diabetes (29.2%), and anemia (26.7%). 32.8% of patients had a history of hospitalization for HF within the previous 12 months. There were 11 034 (35.2%) patients with HFrEF, 6 825 (21.8%) patients with HFmrEF and 13 497 (43.0%) patients with HFpEF. Compared with patients with HFpEF, patients with HFrEF had a lower systolic blood pressure ((124.7±21.1)mmHg(1 mmHg=0.133 kPa) vs. (134.9±22.9)mmHg), faster heart rate ((85±19) beats/minutes vs. (81±19)beats/minutes), and higher percentage of New York Heart Association (NYHA) class Ⅳ, smoking, alcohol, left bundle branch block, and QRS time≥130 ms, and higher levels of blood uric acid, BNP, and NT-proBNP (all P<0.05). Compared with patients with HFmrEF and HFrEF, patients with HFpEF were older, more women, and higher comorbidity burden including hypertension, atrial fibrillation/atrial flutter, anemia and chronic obstructive pulmonary disease (all P<0.05). HFmrEF took a mid-position between HFrEF and HFpEF in age, gender, heart rate, systolic blood pressure, hypertension, atrial fibrillation/atrial flutter, anemia, and chronic obstructive pulmonary disease (all P<0.05). Patients with HFmrEF had the highest proportion of coronary heart disease, myocardial infarction and percutaneous coronary intervention (all P<0.05). During hospitalization, loop diuretics were used in 90.2% of patients, and intravenous inotropics were used in 20.4% of patients. The use of ACEI/ARB/ARNI, β blockers and aldosterone receptor antagonists at discharge were 71.8%, 79.1% and 83.6% in HFrEF and 69.9%, 75.5% and 72.4% in HFmrEF, respectively. The use of digoxin at discharge was 25.3% (HFrEF 36.7%, HFmrEF 23.1%, HFpEF 17.0%). The rates of cardiac resynchronization therapy and implantable cardioverter defibrillator in HFrEF were 2.7% and 2.1%. Conclusions: Among the hospitalized patients with HF in China, coronary heart disease and hypertension are the mostly prevalent causes. HFpEF accounts for a large proportion of hospitalized patients with HF. HFrEF, HFmrEF and HFpEF have different etiology and clinical features. In real-world, there are still large gaps in the effective application of the guideline recommended therapies to HF patients, especially the non-pharmacological therapy option, which needs to be improved further in China.

Time trends in sudden cardiac death risk in heart failure patients with cardiac resynchronization therapy: a systematic review

While data from randomized trials suggest a declining incidence of sudden cardiac death (SCD) among heart failure patients, the extent to which such a trend is present among patients with cardiac resynchronization therapy (CRT) has not been evaluated. We therefore assessed changes in SCD incidence, and associated factors, in CRT recipients over the last 20 years. Literature search from inception to 30 April 2018 for observational and randomized studies involving CRT patients, with or without defibrillator, providing specific cause-of-death data. Sudden cardiac death was the primary endpoint. For each study, rate of SCD per 1000 patient-years of follow-up was calculated. Trend line graphs were subsequently constructed to assess change in SCD rates over time, which were further analysed by device type, patient characteristics, and medical therapy. Fifty-three studies, comprising 22 351 patients with 60879 patient-years of follow-up and a total of 585 SCD, were included. There was a gradual decrease in SCD rates since the early 2000s in both randomized and observational studies, with rates falling more than four-fold. The rate of decline in SCD was steeper than that of all-cause mortality, and accordingly, the proportion of deaths which were due to SCD declined over the years. The magnitude of absolute decline in SCD was more prominent among CRT-pacemaker (CRT-P) patients compared to those receiving CRT-defibrillator (CRT-D), with the difference in SCD rates between CRT-P and CRT-D decreasing considerably over time. There was a progressive increase in age, use of beta-blockers, and left ventricular ejection fraction, and conversely, a decrease in QRS duration and antiarrhythmic drug use. Sudden cardiac death rates have progressively declined in the CRT heart failure population over time, with the difference between CRT-D vs. CRT-P recipients narrowing considerably.

Cardiac resynchronization and implantable defibrillators in adults with congenital heart disease.

Cardiac resynchronization therapy (CRT) and implantable cardioverter defibrillators (ICDs) are well-established therapies for adult patients with heart failure that have been shown to improve morbidity and mortality. However, the benefits and indications for use in adults with congenital heart disease (ACHD) are less defined with no significant large prospective studies in this population. There are, however, multiple retrospective studies that demonstrate the efficacy of these devices in the ACHD population. These indicate a role for both CRT and ICDs in select patients with ACHD. The clinician and patient must balance the risks and benefits, summarized in complex evidence that reflects the heterogeneity of the ACHD patient group, and apply them in a patient-specific manner to optimize the utility of CRT and ICDs.

Implantable cardioverter defibrillator and cardiac resynchronization therapy use in New Zealand (ANZACS-QI 33).

BackgroundThe ANZACS‐QI Cardiac Implanted Device Registry (ANZACS‐QI DEVICE) collects nationwide data on cardiac implantable electronic devices in New Zealand (NZ). We used the registry to describe contemporary NZ use of implantable cardioverter defibrillator (ICD) and cardiac resynchronization therapy (CRT).MethodsAll ICD and CRT Pacemaker implants recorded in ANZACS‐QI DEVICE between 1 January 2014 and 31 December 2017 were analyzed.ResultsOf 1579 ICD implants, 1152 (73.0%) were new implants, including 49.0% for primary prevention and 51.0% for secondary prevention. In both groups, median age was 62 years and patients were predominantly male (81.4% and 79.2%, respectively). Most patients receiving a primary prevention ICD had a history of clinical heart failure (80.4%), NYHA class II‐III symptoms (77.1%) and LVEF ≤35% (96.9%). In the secondary prevention ICD cohort, 88.4% were for sustained ventricular tachycardia or survived cardiac arrest from ventricular arrhythmia. Compared to primary prevention CRT Defibrillators (n = 155), those receiving CRT Pacemakers (n = 175) were older (median age 74 vs 66 years) and more likely to be female (38.3% vs 19.4%). Of the 427 (27.0%) ICD replacements (mean duration 6.3 years), 46.6% had received appropriate device therapy while 17.8% received inappropriate therapy. The ICD implant rate was 119 per million population with regional variation in implant rates, ratio of primary prevention ICD implants, and selection of CRT modality.ConclusionIn contemporary NZ practice three‐quarters of ICD implants were new implants, of which half were for primary prevention. The majority met current guideline indications. Patients receiving CRT pacemaker were older and more likely to be female.

P1631Machine-learning defined predictors of mortality in ischemic and non-ischemic heart failure patients undergoing CRT-P or CRT-D implantation

Abstract Background Both Cardiac Resynchronization Therapy Pacemakers (CRT-P) and CRT Defibrillators (CRT-D) improve mortality in heart failure patients with reduced ejection fraction and wide QRS complex. However, not every patient benefits equally from each type of treatment and determinants of mortality may vary across the subgroups of patients with different etiologies and devices. Purpose Our aim was to investigate the differences in the predictors of long-term mortality in heart failure patients with different etiologies undergoing CRT-P or CRT-D implantation using machine learning. Methods We created 4 separate random forest models to predict 5-year all-cause mortality (models for ischemic and non-ischemic etiology in both CRT-P and CRT-D subgroups). A registry of 1650 patients (66±10 years, 1258 [76%] males, 751 [46%] CRT-D) was used as the training cohort for the prediction models. Forty-seven pre-implant parameters including cardiovascular risk factors and clinical variables were utilized to train our models. For each clinical parameter, we calculated the mean decrease in Gini impurity (dG). Based on the extent of decline, the 10 most important features were selected for each model. To keep the data comparable between the different models, we took the union of these features and plotted the results on radar charts. Results There were 879 (53%) deaths during the follow-up period. The mortality benefit of adding an Implantable Cardioverter Defibrillator could be observed only in ischemic patients (Hazard Ratio = 0.83, 95% Confidence Interval: 0.72–0.97, p&lt;0.005), but not in the entire cohort or in patients with non-ischemic etiology. In patients with non-ischemic etiology, the pattern of mortality predictors were almost similar: in CRT-P patients the most important predictors were age, serum urea levels and left ventricular ejection fraction (LVEF) (dG: 0.114, 0.054 and 0.053, respectively) whereas in the CRT-D subgroup these factors were age, LVEF and serum sodium (dG: 0.116, 0.060 and 0.052, respectively). In CRT-P patients with non-ischemic etiology, the most relevant variables were age serum urea and LVEF in decreasing order (dG: 0.085, 0.060 and 0.050, respectively). The strongest predictors of mortality were age, hemoglobin and serum creatinine in ischemic patients with CRT-D (dG: 0.088, 0.060 and 0.052, respectively). CRT-P vs. CRT-D by ischemic etiology Conclusions In patients with ischemic heart failure, CRT-D was associated with a mortality benefit compared to CRT-P. Our results also suggest that machine-learning may identify distinct patterns in clinical characteristics for a better mortality prediction. Taking these factors into consideration during the management of heart failure patients with CRT, risk stratification and outcomes could be improved.

P5975Diminished LV systolic velocity on tissue Doppler imaging is linked to an amplified risk of lethal arrhythmias independently of LV ejection fraction

Abstract Background Life threatening arrhythmias (LTA) can trigger sudden cardiac death, or provoke implantable cardioverter defibrillator (ICD) discharges that escalate morbidity and mortality. Longitudinal myofibrils predominate in the subendocardium which is uniquely sensitive to arrhythmogenic triggers. Objectives To test the hypothesis that mitral annular systolic velocity (S'), a tissue Doppler index of LV long-axis systolic function, might predict lethal arrhythmias irrespective of LVEF. Methods We analysed data from diverse ICD and cardiac resynchronization therapy defibrillator (CRT-D) patients at 2 London centres. Channelopathies were excluded. S' was averaged from medial and lateral mitral annuli velocities. Primary outcome was time to sustained ventricular tachycardia (VT) or fibrillation (VF) needing device therapy. Results In 302 patients (mean age 68 years, LVEF 32%, 77% male, 52% ischemic, 35% primary prevention, and 53% CRT-D), median S' was 5.1 (IQR: 4.0–6.2) cm/s and lower in CRT-D than ICD subjects. After a median follow-up of 15 months, 56 (19%) subjects had LTA and those who did had a lower S' than those who did not (4.6±1.4 cm/s vs. 5.4±1.7 cm/s, P=0.003-Fig A). Each 1cm/s lower S' correlated to a 43% increased risk of LTA (HR: 0.70, 95% CI: 0.57–0.87, P=0.001) independently of age, gender, β-blocker use, centre, ICD use and LVEF. Adding S' to the baseline model improved net reclassification (P=0.02) implying incremental utility (Fig B). An S' ≤5.6cm/s was the best cut-off, conferring a 2.4-fold higher LTA risk than an S'&gt;5.6 cm/s (95% CI: 1.17–4.37, P=0.02–Fig C). Conclusion A lower S' forecasts an enhanced probability of LTA in cardiac device recipients irrespective of LVEF, and could be used to titrate medical, device and ablative therapies to mitigate future arrhythmic risk.

P5238Rate, cause and costs of Heart Failure hospitalizations following ICD/CRT-D replacement: preliminary data from an Italian multicenter registry

Abstract Background Heart failure hospitalizations (HFHs) likely represent the main health care expenditure also in implantable cardiac defibrillators (ICDs) and cardiac resynchronization therapy defibrillators (CRT-D) recipients yet the event rate of HFH and the associated costs after device replacement or upgrade are unknown. Purpose To report HFH rates and associated costs within 12 months following ICD/CRT-D device replacement or upgrade procedure from ICD to CRT-D. Methods The DEtect long-term COmplications after icD rEplacement (DECODE) was a prospective, single-arm, multicenter cohort study exploring complications in ICD/CRT-D recipients undergoing device replacement or upgrade from ICD to CRT-D. All clinical and survival data of these patients at 12-month follow-up were prospectively analyzed. For each adjudicated HFH, the admission and discharge date were recorded, and ICD-9-CM diagnoses and procedure codes were obtained. The estimated reimbursement for each hospitalization was calculated according to the 2012 Italian national reimbursement rates. Results Between 2013 and 2015, 983 patients (mean age = 71 years, mean LVEF = 35%, NYHA class I/II = 75.6%) were enrolled: 900 (91.6%) patients underwent device replacement (446 ICD/454 CRT-D) and 83 (8.4%) upgrade from ICD to CRT-D. After 12 months, 66 (6.7%) patients died, 40 (60.6%) for cardiovascular reasons. Fifty-five (5.6%) patients experienced at least 1 HFH. Overall, 91 HFH (9.6% event rate 95% CI, 7.7–11.7) occurred. Among the variables tested at univariate analysis, only LVEF ≤35%, AF history and renal disease were confirmed as HFH predictors at multivariate analysis. HFH rate was significantly higher following upgrade procedures and occurrence of HFH was associated with an eleven-fold increased mortality risk (95% CI: 5.9 to 20.5; p&lt;0.0001). The cumulative cost associated with HFHs incurred over the 12 months follow-up was 515305 €. The mean cost per HFH was 5662±9497 € [ranging from 3144 € to 64479 €] while the mean cost per patient with events was 9369±12687 €. Conclusion Underlying cardiac disease and renal failure are the main drivers of HFH and mortality, and of higher healthcare expenditures in ICD/CRT-D recipients following device replacement or upgrade. Accurate clinical assessment is needed to support the decision-maker at the time of ICD replacement to take an appropriate clinical and economic sustainable decision. Acknowledgement/Funding None

P287015 year trend in ICD utilization according to the Italian national administrative database: an analysis of age groups

Abstract To achieve a complete coverage of all Implantable Cardioverter Defibrillator (ICD) performed in Italy between 2001 and 2015, data from the National Hospital Discharge Database (SDO: “Scheda di Dimissione Ospedaliera”) were analyzed. Frequencies and implant rate of ICD and Cardiac Resynchronization Therapy/Defibrillator (CRTD) according to the Italian population were computed. Data were analyzed for the following age classes: &lt;50, 50–80, &gt;80. Results Total number of ICD increased from 3141 in 2001 (implant rate 54/million inhabitants) to 23.540 in 2015 (387/million). From 2009 to 2015 CRT-D increased from 2916 in 2009 (49/million) to 8245 in 2015 (136/million), while the proportion of CRT/total ICD from 17% to 35%. Mean age (from 67±12 in 2001 to 68±12 in 2015) and the proportion of males (from 80% to 79%) remained unchanged. Ischemic heart disease was the most frequent diagnosis (55.6% in 2001, 45.4% in 2015). ICD for secondary prevention have been reducing from 55.6% to 13.6% (ventricular tachycardia, VT) and from 18.1% to 5.9% (ventricular fibrillation, VF). The proportion of patients with heart failure (from 23.9% to 47.9%), hypertension (from 11.2% to 16.2%), diabetes mellitus (6.5% to 11.6%) and renal insufficiency (from 4.4% to 8%) increased. The proportion of CRT/ICD remained constant (except for the 2009, where a possible underdiagnosis is very likely), between 43% and 39%. In patients &lt;50 years old the number of ICD increased from 367 (10/million) in 2001 to 1829 (52/million) in 2015; the most frequent diagnosis was idiopathic cardiomyopathy (30%), while ischemic heart disease was present in 20%. An increase of the proportion of patients with the diagnosis of heart failure (from 13.8% to 33.6%), hypertension (from 4.3% to 8.5%), diabetes mellitus (1.5% to 3.9%) and renal insufficiency (from 1.3% to 2.2%) was observed. In patients &gt;80 years old the number of ICD increased from 195 (82/million) in 2001 to 3902 (981/million) in 2015; ischemic heart disease was the most frequent diagnosis (53.8% in 2001, 43.5% in 2015). ICD for secondary prevention reduced from 50.3% to 14,8% (VT) and from 16.4% to 4.1% (VF), with an increase of the proportion of patients with heart failure (from 22.6% to 46.3%), hypertension (from 11.8% to 17.1%), diabetes mellitus (5.6% to 9.9%) and renal insufficiency (from 7.2% to 12.1%). Conclusions There was a steady increase of ICD and CRTD implantation during the last fifteen years, especially in those &gt;80 years; the proportion of patients treated for secondary prevention dramatically reduced since early 2000; an increase of co-morbidities was observed.

2177Cardiac resynchronization therapy in patients greater than 75 years of age - results from the European Society of Cardiology Survey II with 11 088 patients

Abstract Background Cardiac Resynchronization Therapy (CRT) reduces morbidity and mortality in selected patients with heart failure (HF) and electrical dyssynchrony. The median age for patients included in the CRT landmark trials ranged from 62–68 years, therefore limited trial evidence exists on CRT in patients ≥75 years of age. Purpose To assess similarities and differences in patient demographics and implantation practice in different age groups implanted with a CRT device. Methods Between 2015 and 2017, two European Society of Cardiology (ESC) associations, European Heath Rhythm Society and the Heart Failure Association, conducted the CRT Survey II, a survey of CRT implantations in 11,088 patients in 42 ESC member states. Results In our survey 32% of patients included were ≥75 years of age. These patients were more frequently in NYHA Class III or IV, had more comorbidity (including hypertension, atrial fibrillation, anaemia and renal dysfunction) and had significantly higher NT-pro BNP levels than younger patients. Slightly fewer patients ≥75 years of age had LBBB but all groups had the same median QRS duration. Despite substantially more patients ≥75 years of age having HF of ischaemic aetiology compared with those &lt;65 year of age, far fewer patients in oldest age group category were implanted with a CRT-defibrillator (CRT-D) compared with those in the youngest group. CRT Survey II Patients by Age Categories Demographics Age &lt;65 years Age 65–74 years Age ≥75 years N 3478 (32%) 4025 (36%) 3536 (32%) NYHA class III &amp; IV 52% 59% 66%* Ischaemic HF aetiology 33% 49% 50%* Atrial fibrillation 17% 27% 33* NT proBNP (pg/ml, median, IQR) 1651 (670, 3811) 2319 (1070, 5169) 3510 (1647, 7631)* CRT-D 81% 76% 52%* Peri-procedural complications 5% 6% 6% Adverse Events during hospitalization 4% 5% 5% CRT-D, Cardiac resynchronization therapy – defibrillator; HF, heart failure; IQR, interquartile range. *Differences between groups is significant with p&lt;0.001. Conclusions Patients ≥75 years of age had greater comorbidity and experienced more symptoms from their heart failure. However, they did not suffer more complications or adverse events during the index hospitalization, suggesting that CRT may safely be offered to elderly patients. Acknowledgement/Funding The work was supported by EHRA, the HFA, Biotronik, Boston Scientific, Medtronic, Sorin, St. Jude, Abbott, Bayer, Bristol-Myers Squibb and Servier

P3800Defibrillation for right ventricular dysfunction - An echocardiographic method for therapy selection

Abstract Introduction Cardiac resynchronization therapy (CRT) is recommended for heart failure (HF) patients with left ventricular ejection fraction (LVEF) &lt;35% and QRS&gt;130 mseg. We aim to identify if baseline transthoracic echocardiographic (TTE) data can predict the need for defibrillation therapies in a primary prevention HF population referred for CRT implant. Methods We analyzed 119 consecutive HF patients in primary prevention referred for CRT implantation between 2004 and 2016. All patients underwent TTE before implantation. During a mean follow-up time of 58.4±33.9 months, all patients were evaluated with device interrogation every 6 months. In order to determine which parameters can predict sustained ventricular tachycardia (VT) or ventricular fibrillation (VF) occurrence, a multivariate analysis was performed including previous medical history, baseline laboratorial, electro and echocardiographic data. Results We included 86.6% (n=106) males, mean age at implant 65.5±9.7 years. A CRT-defibrillator (CRT-D) was implanted in 82 (64.2%) patients and a VT or VF was documented in 16 patients (13.4%). Baseline characteristics are presented in the table. After multivariate analysis, baseline right ventricular dysfunction (defined as TAPSE≤18mm) was an independent predictor for VT or VF occurrence (OR=4.83, 95CI 1.67–6.25, p=0.002). Baseline characteristics VT/VF (n=16) No VT/VF (n=103) P-value Age (years, mean ± SD) 62,4±7,9 66,2±9,5 0,135 Female gender (n, %) 2 (12,5) 14 (15,1) 0,572 Ischemic cardiomyopathy (n, %) 7 (43,8) 21 (22,6) 0,073 NYHA III + IV (n, %) 13 (81,3) 76 (73,8) 0,984 QRS width (mseg, mean ± SD) 168,5±19,5 177,6±22,2 0,142 Atrial fibrillation (n, %) 5 (31,3) 17 (18,3) 0,089 LVEF (%, mean ± SD) 24,6±4,8 26,3±6,3 0,302 TAPSE (mm, mean ± SD) 14,9±4,9 17,9±4,3 0,034 PASP (mmHg, mean ± SD) 48,5±9,4 43,5±14,6 0,419 Mitral regurgitation (moderate or greater, n, %) 5 (31,3) 24 (28,9) 0,077 iVol (mL/m2, mean ± SD) 134,2±36,6 128,7±44,1 0,690 CRT-D implantation (n, %) 16 (100,0) 60 (64,5) 0,002 Conclusion In a real-world HF population, right ventricular dysfunction defined by echocardiography was an independent predictor for VT or VF occurrence. This may help more accurate patient selection for CRT-D implantation.

Comparison between cardiac resynchronization therapy with and without defibrillator on long-term mortality: A propensity score matched analysis

BackgroundCardiac resynchronization therapy (CRT)-defibrillator (CRT-D) has been more widely implanted than CRT-pacemaker (CRT-P) in patients of heart failure with reduced ejection fraction and prolonged QRS duration. However, the superiority of CRT-D over CRT-P in improving prognosis has not been well established. MethodsConsecutive patients who underwent CRT implantation between 2005 and 2016 were retrospectively recruited and followed up to December 2017. Baseline characteristics were collected and all-cause mortality was compared between CRT-D and CRT-P recipients. Propensity score matched analysis was further performed to validate the results. ResultsA total of 345 patients (219 CRT-D, 126 CRT-P) were included. During a median follow-up of 36 months, there were 81 deaths (37.0%) in the CRT-D group compared to 56 deaths (44.4%) in the CRT-P group. There was no significant difference in the risk of mortality between CRT-D and CRT-P groups [hazard ratio (HR) 0.99, 95% CI 0.70–1.40, p = 0.95]. Propensity score matching yielded 111 cases per group, and there was no significant difference in the risk of mortality between CRT-D and CRT-P groups (HR 0.87, 95%CI 0.57–1.34, p = 0.53). No significant difference between CRT-D and CRT-P in reducing mortality was observed in any pre-specified subgroups, although the difference between CRT-D and CRT-P was more pronounced in patients with left bundle branch block (p = 0.01 for interaction). ConclusionsCRT-D did not reduce all-cause mortality compared with CRT-P in this retrospective propensity score matched study. A comprehensive score system incorporating multiple factors is needed for risk stratification and guidance on device selection.

Predictors of appropriate interventions and mortality in patients with implantable cardioverter-defibrillators.

Additional risk assessment in patients with heart failure referred for implantable cardioverter‑defibrillator (ICD) implantation as primary prevention is needed. A reduction in left ventricular ejection fraction (LVEF) seems to lack sufficient sensitivity and specificity to be used for identification of patients at the highest risk of sudden cardiac death. The aim of this study was to identify short- and long‑term predictors of appropriate implantable cardioverter‑defibrillator therapy as well as predictors of long‑term mortality in patients with an ICD or cardiac resynchronization therapy defibrillator (CRT‑D). In this retrospective study, data from 457 patients who had an ICD or CRT‑D implanted between 2011 and 2017 were analyzed. During the median follow‑up of 31 months (interquartile range, 17-52 months), 153 patients died (33.9%) and 140 had appropriate interventions (31%). In a multivariate Cox regression analysis, implantation for secondary prevention (hazard ratio [HR], 2.49; P <0.001), severe mitral valve disease (HR, 2.17; P <0.001), and previous myocardial infarction (HR, 1.68; P = 0.009) were predictors of appropriate intervention. Resynchronization therapy (HR, 0.59; P = 0.025) and severe mitral valve disease (HR, 2.42; P <0.001) were predictors of appropriate intervention in primary prevention. Body mass index, hemoglobin concentrations, LVEF, diabetes, and left atrial diameter were significant predictors of death. Implantation of ICD or CRT‑D as secondary prevention was a potent predictor of appropriate intervention, while resynchronization therapy and severe mitral regurgitation predicted ICD therapy in primary prevention. In patients with ICD or CRT-D, independent predictors of mortality included: body mass index, hemoglobin concentrations, LVEF, diabetes, and left atrial diameter.

Atrial Dyssynchrony: A New Predictor for Atrial High-Rate Episodes in Patients with Cardiac Resynchronization Therapy

Background: Heart failure may induce atrial dyssynchrony. We aim to investigate whether preimplantation left atrial (LA) dyssynchrony could predict newly detected atrial high-rate episodes (AHRE) after receiving cardiac resynchronization therapy defibrillator (CRT-D). Methods: We conducted a retrospective analysis of consecutive patients who received CRT-D for standard indications and without a history of atrial fibrillation. The standard deviation of the time-to-peak strain in each LA segment during ventricular systole (SDs) and late diastole (SDa) were calculated to quantify LA dyssynchrony using two-dimensional speckle tracking echocardiography before device implantation. Patients were divided into the AHRE group and the AHRE-free group, depending on the presence of AHRE during device interrogation. Results: Thirty-one patients (28%) had newly detected AHRE during a mean follow-up of 21 ± 9 months. Patients in the AHRE group had higher SDs (8.2 ± 2.6% vs. 6.3 ± 2.3%, p < 0.001) and SDa (5.4 ± 1.8% vs. 4.1 ± 1.4%, p < 0.001) values before implantation than patients in the AHRE-free group. In the multivariate logistic analysis, both SDs (OR 1.325, 95% CI: 1.074–1.636, p =0.009) and SDa (OR: 1.499, 95% CI: 1.071–2.098, p= 0.018) were independent predictors of newly detected AHRE. At a cutoff value of 7.4% for SDs and 5.3% for SDa, the Kaplan-Meier survival analysis showed that patients with higher SDs and SDa had significantly increased risks of newly detected AHRE after receiving CRT-D. Conclusions: Dyssynchronous LA lengthening and contraction could assist in the prediction of newly detected AHRE in patients with CRT-D.

Exercise Interventions in Patients With Implantable Cardioverter-Defibrillators and Cardiac Resynchronization Therapy: A SYSTEMATIC REVIEW AND META-ANALYSIS.

Physical activity improves outcomes across a broad spectrum of cardiovascular disease. The safety and effectiveness of exercise-based interventions in patients with implantable cardioverter-defibrillators (ICDs) including cardiac resynchronization therapy defibrillators (CRT-Ds) remain poorly understood. We identified clinical studies using the following search terms: "implantable cardioverter-defibrillators"; "ICD"; "cardiac resynchronization therapy"; "CRT"; and any one of the following: "activity"; "exercise"; "training"; or "rehabilitation"; from January 1, 2000 to October 1, 2015. Eligible studies were evaluated for design and clinical endpoints. A total of 16 studies were included: 8 randomized controlled trials, 5 single-arm trials, 2 observational cohort trials, and 1 randomized crossover trial. A total of 2547 patients were included (intervention groups = 1215 patients, control groups = 1332 patients). Exercise interventions varied widely in character, duration (median 84 d, range: 23-168 d), and follow-up time (median 109 d, range: 23 d to 48 mo). Exercise performance measures were the most common primary endpoints (87.5%), with most studies (81%) demonstrating significant improvement. Implantable cardioverter-defibrillator shocks were uncommon during active exercise intervention, with 6 shocks in 635 patients (0.9%). Implantable cardioverter-defibrillator shocks in follow-up were less common in patients receiving any exercise intervention (15.6% vs 23%, OR = 0.68; 95% CI, 0.48-0.80, P < .001). (Equation is included in full-text article.)O2 peak improved significantly in patients receiving exercise intervention (1.98 vs 0.36 mL/kg/min, P < .001). In conclusion, exercise interventions in patients with ICDs and CRT-Ds appear safe and effective. Lack of consensus on design and endpoints remains a barrier to broader application to this important patient population.

Projected longevities of cardiac implantable defibrillators: a retrospective analysis over the period 2007-17 and the impact of technological factors in determining longevity.

Implanters of cardiac implantable electronic devices cannot easily choose devices by longevity as usually current models only have projected longevity data since those with known performance are obsolete. This study examines how projected device longevities are derived, the influencing factors, and their roles in guiding model choice. Ninety-eight implantable cardioverter-defibrillator (ICD) and cardiac resynchronization therapy-defibrillator (CRT-D) models released in Europe in 2007-17 were analysed for reported battery capacities, projected longevities for standardized settings stipulated by the French Haute Autorité de Santé (HAS) and manufacturer-chosen settings. Battery capacities and HAS projected longevities increased during the study period. Based on current drain estimation, therapy functions consumed only a small portion (2-7%) of the battery energy for single- and dual-chamber ICDs, but up to 50% (from biventricular pacing) for CRT-Ds. Large differences exist between manufacturers and models both in terms of battery capacity and energy consumption. Battery capacity is not the sole driver of longevity for electronic implantable cardiac devices and, particularly for ICDs, the core function consume a large part of the battery energy even in the absence of therapy. Providing standardized current drain consumption in addition to battery capacity may provide more meaningful longevity information among implantable electronic cardiac devices.

Longest Paced versus Sensed Electrical Delay Programming in Cardiac Resynchronization Therapy Defibrillator Patients with Quadripolar LV Leads: Results from the PASED-CRT Randomized Trial

Introduction Cardiac resynchronization therapy (CRT) is a well-established treatment for patients with drug refractory heart failure. The PASED-CRT trial (NCT-02803775) compared the efficacy of the longest RVsense to LVsense activation time (sLAT) versus the longest RVpace to LVsense activation time (pLAT) as the site of the LV pacing cathode on quadripolar LV leads. Methods The PASED-CRT trial is a single site, double blind, randomized, prospective trial. Patients were randomized to sLAT or pLAT in a 1:1 ratio. The site of Left ventricular pacing was programmed bases on the longest electrical delay measured and maintained thru 3 months. Blinded physicians and assessors compared the 6-minute hall walk test (6MWT), NYHA, MLWHF, and Clinical Composite Score (CCS) at 3 months. Results N=92 patients (20%F) 66 (±11.3 years) were randomized and programmed per protocol. Patients and physicians were blinded to programming assignment. Baseline patient characteristics were comparable between groups. N=38 sLAT and N=34 pLAT completed the 3 month visit for the final analysis. The pLAT group had a greater CCS compared 82.4% vs. the sLAT 55.3% (P=0.016) and had a mean 20.63m increase over the sLAT in 6MWT distance at 3 months. (P=N/S) Conclusions Utilizing the pLAT demonstrated improved 6MWT distance and a significant difference in CCS over the programming to the sLAT. These results should be considered in patients with intrinsic conduction and those without as no measurement is currently available. Future studies with longer follow-ups are warranted to confirm these findings.

Economic Implications of Longer Battery Longevity of Cardiac Resynchronization Therapy Defibrillator Devices in the United States

Introduction The economic impact of generator longevity differs by indicated patient population, as the magnitude of Cardiac Resynchronization Therapy Defibrillator devices (CRT-Ds) survival benefit varies by indication and so does the expected survival of the patient. The objective of this study is to understand cost savings associated with incremental years of battery life from a U.S. payer perspective. Methods Patient data from 7 prospective trials were used to project expected patient survival. Weibull/Gompertz statistical models were fitted to data from: (a) InSync III Marquis, MIRACLE, MIRACLE ICD, PROSPECT and Adaptive CRT for Class III/IV patients, (b) REVERSE for Class II patients, and (c) BLOCK-HF for AV Block patients. Mean battery longevity scenarios used half-yearly increments. A payer perspective based on the 2018 U.S. Centers for Medicare and Medicaid Services (CMS) Medicare program was used. Results Testing mean battery scenarios from 5.5 to 8.5 years, 6 additional months of device longevity result in average Medicare savings of $2,692 for Class III/IV patients, $5,429 for Class II patients and $3,754 for AV Block patients. Additional economic benefits associated with avoiding changeout-related complications were not included in these device cost projections. Conclusions Increasing CRT-D battery life can result in reductions in device-related cost across all indicated patient groups, with economic benefits being maximized among NYHA Class II subjects. But the relative impact lessens as additional battery years are added.

Comprehensive Economic Evaluation of Automatic Optimization in Cardiac Resynchronization Defibrillators (CRT-Ds): Cost-Effectiveness Analysis - A Canadian Perspective

Introduction Innovative algorithms allowing automated optimization of cardiac resynchronization therapy defibrillators (CRT-Ds), have been introduced in Canada. These automatically adjust the A-V interval and appropriately withhold right ventricular (RV) pacing during times it may not be needed. These “adaptive” algorithms may increase response to therapy, as network meta-analyses have demonstrated, reduce hospitalizations, and drastically reduce the need of periodic ultrasound-driven device optimization. We wanted to investigate the cost-effectiveness of these algorithms from a Canadian provincial Healthcare system. Methods Markov Modelling informed by the AdaptivCRT Clinical Trial and propensity score matching with earlier CRT-D trials. Costs of device implantations were achieved from Ontario Case Costing Initiative. Other costs were obtained through Canadian literature reviews. 3% discounting of costs and outcomes was applied. Results The predicted patient survival was 10.97 years with adaptive algorithms and 10.50 years with traditional CRT, a 4.5% increase over lifetime. Deterministic results suggested adaptive algorithms produce 0.31 quality-adjusted life years (QALYs) more than traditional CRT (7.41 vs. 7.10). The cost saving per life-year gained with adaptive algorithms was CAD 2,118.47. The cost saving per QALY was CAD 3,133.83. Conclusions The use of adaptive algorithms was projected to improve average patient survival, quality of life, while avoiding costs. Avoidance of AF-related admissions and cardiac ultrasounds will make the benefits more pronounced.

Association of Remote Monitoring With Survival in Heart Failure Patients Undergoing Cardiac Resynchronization Therapy: Retrospective Observational Study.

BackgroundRemote monitoring is an established, guideline-recommended technology with unequivocal clinical benefits; however, its ability to improve survival is contradictory.ObjectiveThe aim of our study was to investigate the effects of remote monitoring on mortality in an optimally treated heart failure patient population undergoing cardiac resynchronization defibrillator therapy (CRT-D) implantation in a large-volume tertiary referral center.MethodsThe population of this single-center, retrospective, observational study included 231 consecutive patients receiving CRT-D devices in the Medical Centre of the Hungarian Defence Forces (Budapest, Hungary) from January 2011 to June 2016. Clinical outcomes were compared between patients on remote monitoring and conventional follow-up.ResultsThe mean follow-up time was 28.4 (SD 18.1) months. Patients on remote monitoring were more likely to have atrial fibrillation, received heart failure management at our dedicated heart failure outpatient clinic more often, and have a slightly lower functional capacity. Crude all-cause mortality of remote-monitored patients was significantly lower compared with patients followed conventionally (hazard ratio [HR] 0.368, 95% CI 0.186-0.727, P=.004). The survival benefit remained statistically significant after adjustment for important baseline parameters (adjusted HR 0.361, 95% CI 0.181-0.722, P=.004).ConclusionsIn this single-center, retrospective study of optimally treated heart failure patients undergoing CRT-D implantation, the use of remote monitoring systems was associated with a significantly better survival rate.