Ten-year trends in cardiac implantable electronic devices in New Zealand: a national data linkage study (ANZACS-QI 51).

BACKGROUND: Implant rates for cardiac implantable electronic devices (CIED), including permanent pacemakers (PPM) and implantable cardioverter defibrillators (ICD), have increased globally in recent decades. AIMS: This is the first national study providing a contemporary analysis of national CIED implant trends by sex-specific age groups over an extended period. METHODS: Patient characteristics and device type were identified for 10 years (2009-2018) using procedure coding in the National Minimum Datasets, which collects all New Zealand (NZ) public hospital admissions. CIED implant rates represent implants/million population. RESULTS: New PPM implant rates increased by 4.6%/year (P < 0.001), increasing in all age groups except patients <40 years. Males received 60.1% of new PPM implants, with higher implant rates across all age groups compared with females. The annual increase in age-standardised implant rates was similar for males and females (3.4% vs 3.0%; P = 0.4). By 2018 the overall PPM implant rate was 538/million. New ICD implant rates increased by 4.2%/year (P < 0.001), increasing in all age groups except patients <40 and ≥ 80 years. Males received 78.1% of new ICD implants, with higher implant rates across all age groups compared to females. The annual increase in age-standardised implant rates was higher in males compared with females (3.5% vs 0.7%; P < 0.001). By 2018 the overall ICD implant rate was 144/million. CONCLUSION: CIED implant rates have increased steadily in NZ over the past decade but remain low compared with international benchmarks. Males had substantially higher CIED implant rates compared with females, with a growing gender disparity in ICD implant rates.

Regional variation in cardiac implantable electronic device implants trends in New Zealand over the past decade (ANZACS-QI 54).

BACKGROUND: Permanent pacemaker (PPM) and implantable cardioverter defibrillator (ICD) implant rates have increased in New Zealand over the past decade. AIMS: To provide a contemporary analysis of regional variation in implant rates. METHODS: New PPM and ICD implants in patients aged ≥15 years were identified for 10 years (2009-2018) using procedure coding in the National Minimum Datasets, which collects all New Zealand public hospital admissions. Age-standardised new implant rates per million adult population were calculated for each of the four regions (Northern, Midland, Central and Southern) and the 20 district health boards (DHB) across those regions. Trend analysis was performed using joinpoint regression. RESULTS: New PPM implant rates increased nationally by 3.4%/year (P < 0.001). The Northern region had the highest new PPM implant rate, increasing by 4.5%/year (P < 0.001). Excluding DHB with <50 000 people, the new PPM implant rate for 2017/2018 was highest in Counties Manukau DHB (854.3/million; 95% confidence interval (CI): 774.9-933.6/million) and lowest in Canterbury DHB (488.6/million; 95% CI: 438.1-539.0/million). New ICD implant rates increased nationally by 3.0%/year (P = 0.002). The Midland region had the highest new ICD implant rate, increasing by 3.8%/year (P = 0.013). Excluding DHB with <50 000 people, the new ICD implant rate for 2017-2018 was highest in the Bay of Plenty DHB (228.5/million; 95% CI: 180.4-276.6/million) and lowest in Canterbury DHB (90.2/million; 95% CI: 69.9-110.4/million). CONCLUSION: There was significant variation in PPM and ICD implant rates across regions and DHB, suggesting potential inequity in patient access across New Zealand.

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

BACKGROUND: The 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). METHODS: All ICD and CRT Pacemaker implants recorded in ANZACS-QI DEVICE between 1 January 2014 and 31 December 2017 were analyzed. RESULTS: Of 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. CONCLUSION: In 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.

Impact of cardiac resynchronisation therapy on burden of hospitalisations and survival: a retrospective observational study in the Northern Region of New Zealand.

OBJECTIVE: Cardiac resynchronisation therapy (CRT) devices have been shown to improve heart failure (HF) symptoms, survival and improve quality of life (QoL). We evaluated the overall impact of CRT on recurrent hospitalisations and survival in real-world patients with HF. DESIGN: Retrospective observational study. SETTING: Northern region of New Zealand. PARTICIPANTS: Patients with HF who underwent CRT device implantation in between 2008 and 2014 were followed up for 1 year. INTERVENTIONS: CRT. PRIMARY AND SECONDARY OUTCOMES MEASURED: Survival, all-cause hospitalisations, length of stay, from which days alive and out of hospital (DAOH) were calculated. RESULTS: 177patients were included, of whom eight died (4.5%) within 1 year of follow-up. Pre-CRT implantation, 83% of all patients had been hospitalised for a total 248 hospitalisation events. Following CRT, 47 patients (27%) were readmitted to hospital within 1 year (total of 98 admissions; p<0.01 compared with pre-device implant). Length of hospital stay was significantly shorter than in the year prior to CRT implantation at a median of 4 (IQR 2-6) vs 7 (IQR 3.5-10.5) days (p=0.03). An increase in the median number of DAOH was observed from 362 (IQR 355-364) to 365 (IQR 364-365) (p<0.01) after CRT implant. The improvement in DAOH was seen regardless of gender and type of CRT devices. Greater DAOH was also seen in those with non-ischaemic cardiomyopathy and Caucasians. CONCLUSION: After CRT implant, patients with HF have greater DAOH with reduction of total hospitalisation and fewer hospital days. These results support CRT devices use as a treatment option for appropriate HF patients. DAOH represents an easily measured, patient-centred endpoint that may reflect effectiveness of interventions in future CRT studies.

Outcomes of patients with heart failure after primary prevention ICD unit generator replacement.

OBJECTIVE: Data describing outcomes after implantable cardioverter-defibrillator (ICD) unit generator replacement in patients with heart failure (HF) with primary prevention devices are limited. METHOD: Data on patients with HF who underwent primary prevention ICD/cardiac resynchronisation therapy-defibrillator (CRT-D) implantation from 2007 until mid-2015 who subsequently received unit generator replacement were analysed. Outcomes assessed were mortality, appropriate ICD therapy and shock, and procedural complications. RESULTS: 61 of 385 patients with HF with primary prevention ICD/CRT-D undergoing unit generator replacement were identified. Follow-up period was 1.8±1.5 years after replacement. 43 (70.5%) patients had not received prior appropriate ICD therapy prior to unit replacement. The cumulative risks of appropriate ICD therapy at 1, 3 and 5 years after unit replacement in those without prior ICD therapy were 0%, 6.2% and 50% compared with 6.2%, 59.8% and 86.6%, respectively (p=0.005) in those with prior ICD therapies. No predictive factors associated with appropriate ICD therapy after replacement could be identified. 41 (32.8%) patients no longer met guideline indications at the time of unit replacement but risks of subsequent appropriate ICD interventions were not different compared with those who continued to meet primary prevention ICD indications.The 5-year mortality risk after unit replacement was 18.4% and there were high procedural complication rates (9.8%). CONCLUSION: No predictive marker successfully stratified patients no longer needing ICD support prospectively. Finding such a marker is important in decision-making about device replacement particularly given the concerns about the complication rates. These factors should be considered at the time of ICD unit replacement.

Utilization of cardiac resynchronization therapy in patients with heart failure in the Northern Region of New Zealand.

BACKGROUND: Cardiac resynchronization therapy (CRT) has been shown to improve morbidity and mortality for heart failure (HF) patients. Little is known about the trends in CRT use and outcomes of these patients in New Zealand. METHOD: Mortality, hospitalization events and complications in HF patients in the Northern Region of New Zealand implanted with CRT devices from Jan-2007 to June-2015 were reviewed. RESULTS: Two-hundred patients underwent CRT implantation during the study period. There was a gradual increase in CRT-D implantation (n = 157) but the number remained static for CRT-P (n = 43). Patients who received CRT-P were older (mean age 65.9 ± 14.0 years vs 61.5 ± 10.2 years, P < 0.0007) but had a higher left ventricular ejection fraction (LVEF) (33.7 ± 10.5% vs 24.7 ± 6.1%, P < 0.0001) than those undergoing CRT-D implant procedures. During a median follow-up of 4 (2.8) years, 29 (14.5%) patients (14.7% in CRT-D vs 13.9% in CRT-P, P = 0.91) had died. HF was the cause of death in 73.9% of the patients. There was no difference in all-cause mortality between patients with CRT-D and CRT-P. CONCLUSIONS: Despite the proven benefits of CRT in selected HF patients, there continued to be under-utilization of these devices in HF patients in the Northern Region. Reasons for under-utilization of these devices need further exploration. These data should be useful for benchmarking individual patient management and national practice against wider experience in the country.

Long-term outcomes of heart failure patients who received primary prevention implantable cardioverter-defibrillator: An observational study.

BACKGROUND: Implantable cardioverter-defibrillator (ICD) therapy is indicated for selected heart failure patients for the primary prevention of sudden cardiac death. Little is known about the outcomes in patients selected for primary prevention device therapy in the northern region of New Zealand. METHOD: Heart failure patients with systolic dysfunction who underwent primary prevention ICD/cardiac resynchronization therapy-defibrillator (CRT-D) implantation between January 1, 2007, and June 1, 2015, were included. Complications, mortality, and hospitalization events were reviewed. RESULTS: Three hundred and eighty-five primary prevention devices were implanted (269 ICD, 116 CRT-D). Mean age at implant was 59.1 ± 11.4 years. Mean duration of follow-up was 3.64 ± 2.17 years. The commonest cause of death was heart failure (41.8%). Only 2 patients died from sudden arrhythmic death. The 5-year heart failure mortality rate was 6%, whereas the 5-year sudden arrhythmic death rate was 0.3%. Heart failure hospitalizations were commoner in those who received ICD than CRT-D (67.7% vs 25.8%, P < .001). Maori patients have low implant rates (14%) with relatively high rates of admissions with heart failure and ventricular arrhythmia admissions. CONCLUSIONS: Even in appropriately selected heart failure patients who received primary prevention devices, only a small percentage died as a result of sudden arrhythmic death. CRT-D should be the device of choice where appropriate in heart failure patients. Significant challenges remain to improve access to device therapy and maximize benefit to those who do get implanted.

Gender differences in the use of primary prevention ICDs in New Zealand patients with heart failure.

OBJECTIVE: Women have been under-represented in randomised clinical trials for primary prevention implantable cardioverter defibrillators (ICDs), and there are concerns about the efficacy of devices between genders. Our study aimed to investigate gender differences in the use of primary prevention ICD in patients with heart failure from the northern region of New Zealand. METHODS: Patients with heart failure with systolic dysfunction who received primary prevention ICD/cardiac resynchronisation therapy-defibrillator (CRT-D) in the northern region of New Zealand from 1 January 2007 to 1 June 2015 were included. Complications, mortality and hospitalisation events were reviewed. RESULTS: Of the 385 patients with heart failure implanted with ICD/CRT-D, women comprised 15.1% (n=58), and no change in utilisation of these devices was observed over the study period among women. Women were more likely to have non-ischaemic cardiomyopathy and have higher perioperative complications (8.6% vs 2.5%, P=0.02), with non-significant higher trend towards increased lead displacement (5.2% vs 1.8%, P=0.12). Women appeared to have lower all-cause (10.3% vs 18.7%, P=0.12), cardiovascular (5.2% vs 11.9%, P=0.13) and heart failure (3.5% vs 7.9%, P=0.22) mortalities but was not statistically significant. There were no gender differences in all-cause (70.7% vs 67%, P=0.58) or heart failure (19% vs 25%, P=0.32) readmissions. CONCLUSION: Perioperative complications were significantly more common in women referred for ICD/CRT-D. Although there has been a significant increase in ICD implantation rates, gender differences in the use of these devices still exist in New Zealand, in keeping with the demographics of ischaemic heart disease and systolic dysfunction between genders.

Adding Defibrillation Therapy to Cardiac Resynchronization on the Basis of the Myocardial Substrate.

BACKGROUND: Patients with nonischemic dilated cardiomyopathy (DCM) may be at lower risk for ventricular arrhythmias compared with those with ischemic cardiomyopathy (ICM). In addition, DCM has been identified as a predictor of positive response to cardiac resynchronization therapy (CRT). OBJECTIVES: The aim of this study was to investigate the impact of an additional implantable cardioverter-defibrillator over CRT, according to underlying heart disease, in a large study group of primary prevention patients with heart failure. METHODS: This was an observational, multicenter, European cohort study of 5,307 consecutive patients with DCM or ICM, no history of sustained ventricular arrhythmias, who underwent CRT implantation with (n = 4,037) or without (n = 1,270) a defibrillator. Propensity-score and cause-of-death analyses were used to compare outcomes. RESULTS: After a mean follow-up period of 41.4 ± 29.0 months, patients with ICM had better survival when receiving CRT with a defibrillator compared with those who received CRT without a defibrillator (hazard ratio for mortality adjusted on propensity score and all mortality predictors: 0.76; 95% confidence interval [CI]: 0.62 to 0.92; p = 0.005), whereas in patients with DCM, no such difference was observed (hazard ratio: 0.92; 95% CI: 0.73 to 1.16; p = 0.49). Compared with recipients of defibrillators, the excess mortality in patients who did not receive defibrillators was related to sudden cardiac death in 8.0% among those with ICM but in only 0.4% of those with DCM. CONCLUSIONS: Among patients with heart failure with indications for CRT, those with DCM may not benefit from additional primary prevention implantable cardioverter-defibrillator therapy, as opposed to those with ICM.

Prophylactic implantable cardioverter defibrillator in heart failure: the growing evidence for all or Primum non nocere for some?

Heart failure (HF) is a common health problem and has reached epidemic in many western countries. Despite the current era of HF treatment, the risk of sudden cardiac death (SCD) in HF remains significant. Implantable cardioverter defibrillator (ICD) support has been shown to reduce the risk of SCD in patients with HF and impaired left ventricular function. Prophylactic ICD implantation in HF patients seems a logical step to reduce mortality through a reduction in SCD. However, ICD implantation is an invasive procedure, and both short- and long-term complications can occur. This needs to be carefully considered when evaluating the risk-benefit ratio of ICD implantation for individual patients. As the severity of HF increases, the proportion of SCD compared with HF-related deaths decreases. The challenge lies in identifying patients with HF who are at significant risk of SCD and who would most benefit from an ICD in addition to other anti-arrhythmic strategies. This review offers insight on the applicability and practicability of ICD for this growing population.

Sex-specific outcomes with addition of defibrillation to resynchronisation therapy in patients with heart failure.

OBJECTIVE: Among primary prevention patients with heart failure receiving cardiac resynchronisation therapy (CRT), the impact of additional implantable cardioverter defibrillator (ICD) treatment on outcomes and its interaction with sex remains uncertain. We aim to assess whether the addition of the ICD functionality to CRT devices offers a more pronounced survival benefit in men compared with women, as previous research has suggested. METHODS: Observational multicentre cohort study of 5307 consecutive patients with ischaemic or non-ischaemic dilated cardiomyopathy and no history of sustained ventricular arrhythmias having CRT implantation with (cardiac resynchronisation therapy defibrillator (CRT-D), n=4037) or without (cardiac resynchronisation therapy pacemaker (CRT-P), n=1270) defibrillator functionality. Using propensity score (PS) matching and weighting and cause-of-death data, we assessed and compared the outcome of patients with CRT-D versus CRT-P. This analysis was stratified according to sex. RESULTS: After a median follow-up of 34 months (interquartile range 22-60 months) no survival advantage, of CRT-D versus CRT-P was observed in both men and women after PS matching (HR=0.95, 95% CI 0.77 to 1.16, p=0.61, and HR=1.30, 95% CI 0.83 to 2.04, p=0.25, respectively). With inverse-probability weighting, a benefit of CRT-D was seen in male patients (HR 0.78, 95% CI 0.65 to 0.94, p=0.012) but not in women (HR 0.87, 95% CI 0.63 to 1.19, p=0.43). The excess unadjusted mortality of patients with CRT-P compared with CRT-D was related to sudden cardiac death in 7.4% of cases in men but only 2.2% in women. CONCLUSIONS: In primary prevention patients with CRT indication, the addition of a defibrillator might convey additional benefit only in well-selected male patients.

Adherence to the current guidelines for bradycardic pacing in the octogenarian and nonagenarian populations.

AIM: A significant proportion of single-chamber ventricular pacemakers are implanted in octogenarian and nonagenarian patients. We aimed to assess whether the current pacing guideline is adhered for these populations. METHODS: We retrospectively identified patients ≥80 years of age, who received their first pacemaker from July 2010 to June 2013. RESULTS: A total of 356 patients were identified. Mean age was 86.1 years and 82.6 years for single and dual-chamber pacemakers respectively (p<0.05). Total procedure-related complications occurred in 9.5% and were comparable between both groups (p=0.08). At the time of implantation, 185 patients who received single-chamber pacemaker were in sinus rhythm (52%). They were older (86.2±4.3 vs 82.6±2.9, p<0.05), more likely to have ischaemic and valvular heart disease (68 vs 27, p= 0.02 and 22 vs 13, p=0.01, respectively), and cognitive impairment (34 vs 0, p= 0.001). They were also more likely to be discharged to a residential care facility (17 vs 1, p<0.01). CONCLUSION: The utility of dual-chamber pacemaker in this age group remains below expectation and did not comply with current cardiac pacing guidelines. The presence of older age, multiple co-morbidities, cognitive impairment and residential care on discharge likely influenced the type of device implanted.

Applicability of a risk score for prediction of the long-term benefit of the implantable cardioverter defibrillator in patients receiving cardiac resynchronization therapy.

AIMS: The Goldenberg risk score, comprising five clinical risk factors (New York Heart Association class >2, atrial fibrillation, QRS duration >120 ms, age >70 years, and urea >26 mg/dL), may help identify patients in whom the survival benefit of the defibrillator may be limited. We aim at assessing whether this score can accurately predict the long-term all-cause mortality risk of patients receiving cardiac resynchronization therapy (CRT) and identify those who are more likely to benefit from the defibrillator. METHODS AND RESULTS: In this retrospective observational cohort study, 638 patients with ischaemic or non-ischaemic dilated cardiomyopathy who had CRT-defibrillator (CRT-D) (n = 224) vs. CRT-pacemaker (CRT-P) (n = 414) implantation were prospectively followed up for survival outcomes. The long-term outcome of patients with CRT-D vs. CRT-P was compared within risk score categories and in patients with severe renal dysfunction. Mean follow-up in surviving and deceased patients was 62.7 and 32.5 months, respectively. This score showed higher discriminative performance in all-cause mortality prediction in CRT-D vs. CRT-P patients (area under the curve 0.718 ± 0.041 vs. 0.650 ± 0.032, respectively, P = 0.001). In those with scores 0-2, a CRT-D device decreased mortality rates in the first 4 years of follow-up compared with CRT-P (11.3 vs. 24.7%, P = 0.041), but this effect attenuated with longer follow-up duration (21.2 vs. 32.7%, P = 0.078). In this group, the benefit of CRT-D during the follow-up was seen after adjusting for traditional mortality predictors (hazard ratio 0.339, P = 0.001). No significant differences in mortality rates were seen in patients with score ≥3 (57.9% with CRT-D vs. 56.9%, P = 0.8) and those with severe renal dysfunction (92.9% in CRT-D vs. 76.2%, P = 0.17). Similar results were seen following propensity score matching. CONCLUSION: A simple risk stratification score comprising five clinical risk factors may help identify CRT patients who are more likely to benefit from the presence of the defibrillator.

Ventricular arrhythmia storm in the era of implantable cardioverter-defibrillator.

In the era of widespread use of implantable cardioverter-defibrillators (ICDs) for both primary and secondary prevention of sudden cardiac death, a significant proportion of patients experience episodes of multiple ventricular tachycardia/fibrillation over a short period of time requiring device interventions. The episodes are termed ventricular arrhythmia (VA) or electrical storms. VA storm is a tragic experience for patients, with many psychological consequences. Current management for VA storms remains complex. Acutely, administration of ß-blockers, amiodarone and sedation or intubation is generally required to suppress sympathetic tone. Interventional treatment includes catheter ablation and sympathetic blockade by left cardiac sympathetic denervation. Strategies to modify autonomic tone to suppress VAs are the rationale of various novel interventions that have been published in recent studies. All patients with VA storm should be considered for transfer to an experienced high-volume tertiary centre for evaluation and treatment to prevent further recurrence of VA storm.

A minimal or maximal ablation strategy to achieve pulmonary vein isolation for paroxysmal atrial fibrillation: a prospective multi-centre randomized controlled trial (the Minimax study).

AIMS: Pulmonary vein isolation (PVI) is the cornerstone of catheter ablation of atrial fibrillation (AF). The intervenous ridge (IVR) may be incorporated into ablation strategies to achieve PVI; however, randomized trials are lacking. We performed a randomized multi-centre international study to compare the outcomes of (i) circumferential antral PVI (CPVI) alone (minimal) vs. (ii) CPVI with IVR ablation to achieve individual PVI (maximal). METHODS AND RESULTS: Two hundred and thirty-four patients with paroxysmal AF underwent CPVI and were randomized to a minimal or maximal ablation strategy. The primary outcome of recurrent atrial arrhythmia was assessed with 7-day Holter monitoring at 6 and 12 months. PVI was achieved in all patients. Radiofrequency ablation time was longer in the maximal group (46.6 ± 14.6 vs. 41.5 ± 13.1 min; P < 0.01), with no significant differences in procedural or fluoroscopy times. At mean follow-up of 17 ± 8 months, there was no difference in freedom from AF after a single procedure between a minimal (70%) and maximal ablation strategy (62%; P = 0.25). In the minimal group, ablation was required on the IVR to achieve electrical isolation in 44%, and was associated with a significant reduction in freedom from AF (57%) compared with the minimal group without IVR ablation (80%; P < 0.01). CONCLUSION: There was no statistically significant difference in freedom from AF between a minimal and maximal ablation strategy. Despite attempts to achieve PVI with antral ablation, IVR ablation is commonly required. Patients in whom antral isolation can be achieved without IVR ablation have higher long-term freedom from AF (the Minimax study; ACTRN12610000863033).

Cardiac resynchronisation therapy: pacemaker versus internal cardioverter-defibrillator in patients with impaired left ventricular function.

OBJECTIVE: Studies have shown beneficial effects of cardiac resynchronisation therapy (CRT) on mortality among patients with heart failure. However the incremental benefits in survival from CRT with a defibrillator (CRT-D) are unclear. The choice of appropriate device remains unanswered. METHOD: This is a single-centre observational study in a tertiary cardiac centre. Patients (n=500) implanted with a CRT device with pacing alone (CRT-P) (n=354) and CRT-D (n=146) were followed for at least 2 years (mean 29 months, SD 14 months). The primary end point was all-cause mortality. RESULTS: A total of 116 deaths (23.2%) were recorded: 88 (24.8%) and 28 (19.2%), in the CRT-P and CRT-D groups, respectively. At 1 year there was a trend favouring CRT-D (HR 0.54, 95% CI 0.27 to 1.07, p=0.08) but this was attenuated by the 2nd year and became insignificant at the end of follow-up (HR 0.76, 95% CI 0.50 to 1.170, p=0.21). There was no survival benefit from having an internal cardioverter-defibrillator if patients were deemed non-responders to CRT. 27% of the CRT-P patients with ischaemic cardiomyopathy met indications for potential internal cardioverter-defibrillator implantation for primary prevention. These were older patients with poorer baseline function in comparison with CRT-D patients with devices for primary prevention. Once these differences were adjusted for, there was no difference in outcome between the groups. CONCLUSIONS: CRT-D did not offer additional survival advantage over CRT-P at longer-term follow-up, as the clinical benefit of a defibrillator attenuated with time. Further work is needed to define which subset of patients benefit from CRT-D.