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Background The Seattle Heart Failure Model (SHFM) provides accurate estimates of survival in heart failure (HF) patients. The model is, however, not developed for HF patients with cardiac resynchronization therapy (CRT). The aim of this study was to assess the prognostic value of SHFM combined with QRS morphology and CRT-related change in QRS duration in implantable cardioverter defibrillator (ICD) and CRT defibrillator (CRT-D) recipients. Methods All patients who underwent prophylactic ICD implantation at the Leiden University Medical Center since 1996 were included. Baseline SHFM, QRS morphology, and duration before and after device implantation were determined. The regression coefficients of the QRS characteristics derived from a Cox regression analysis were implemented in the SHFM. SHFM-estimated survival was compared with Kaplan-Meier observed survival. Results The current study includes 1,834 defibrillator recipients (63 ± 11 years; 79% male; 53% CRT-D). In 585 (60%) CRT-D recipients a left bundle branch block was present, the mean QRS duration was 147 ± 31 ms before and 151 ± 27 ms after device implantation. After a median follow-up of 4.4 years (25th-75th percentile 2.7-6.4 years), 285 (29%) CRT-D recipients had died. CRT-related decrease in QRS duration adjusted for QRS morphology was associated with improved survival (hazard ratio 1.05/10 ms; 95% confidence interval [CI]: 1.01-1.09; P = 0.02). The estimated 5-year survival of CRT-D recipients after implementation of the QRS characteristic was 70%, and comparable with the observed 5-year survival of 68% (95% CI: 65-72). Conclusion Implementation of native QRS morphology and change in QRS duration due to CRT in the SHFM improves the prognostic value of this model in HF patients with CRT-D. [ABSTRACT FROM AUTHOR]

Aims Mortality and ventricular arrhythmias are reduced in patients responding to cardiac resynchronization therapy (CRT). This response is accompanied by improvement in LVEF, and some patients even outgrow original eligibility criteria for implantable cardioverter-defibrillator ( ICD) implantation. It is however unclear if these patients still benefit from ICD treatment. The current study aimed to evaluate if the incidence of ICD therapy is related to the extent of CRT response. Methods and results All patients who underwent primary prevention CRT-defibrillator implantation were included. They were divided into subgroups according to the reduction in LV end-systolic volume ( LVESV) 6 months after implantation. Pre-defined subgroups were: negative responders (increased LVESV), non-responders (decreased LVESV 0-14%), responders (decreased LVESV 15-29%), and super-responders (decreased LVESV ≥30%). During a median follow-up of 57 months (25th-75th percentile 39-84), 512 patients were studied [101 (20%) negative responders, 101 (20%) non-responders, 149 (29%) responders, and 161 (31%) super-responders]. In the first year of follow-up super-responders received significantly less appropriate ICD therapy (3% vs. 12%; P < 0.001). The 5-year cumulative incidence of appropriate ICD therapy was 31% [95% confidence interval ( CI) 19-43] in negative responders, 39% (95% CI 25-53) in non-responders, 34% (95% CI 25-43) in responders, and 27% (95% CI 18-35) in super-responders, respectively ( p = 0.13). Conclusions The extent of CRT response was associated with a parallel reduction of appropriate device therapy during the first year of follow-up. Thereafter, no association was observed. Furthermore, 23% of super-responders were treated for potentially life-threatening arrhythmias and benefit from ICD treatment. [ABSTRACT FROM AUTHOR]

CKD and ICD Related Complications Introduction Implantable cardioverter defibrillator (ICD) implantation has become an accepted therapy for the prevention of sudden cardiac death. However, serious comorbidities such as chronic kidney disease (CKD) are influencing the beneficial effects of ICD therapy. In this study, the association between kidney function and the occurrence of ICD related complications was assessed. Methods All patients receiving an ICD or cardiac resynchronization therapy-defibrillator between 1996 and 2012 were included. Renal function was categorized as: glomerular filtration rate (GFR) >90, GFR 30-90 or GFR <30 mL/min/1.73 m2. Registered complications were pocket hematoma, pneumothorax, lead complications, and device infection. Results In 3,147 device recipients, 236 patients (7.5%) suffered from at least 1 complication. Patients with a GFR <30 (n = 110) had a higher event rate for hematoma, pneumothorax, and infection. These patients were older, had a higher incidence of hypertension, diabetes, and a lower body mass index (BMI; P < 0.05). After correcting for these risk factors, hematoma remained independently associated with a GFR <30 mL/min (OR 2.7, CI: 1.05-6.9, P = 0.04). Device infection, pneumothorax, and lead complications were not independently associated with a GFR <30 mL/min/1.73 m2. Conclusions Patients with CKD suffered from more ICD related complications than patients without kidney disease. This was partially associated with kidney dysfunction itself as was the case with the occurrence of hematoma. However, the high burden of risk factors associated with device complications in patients with renal disease played an important role as well. [ABSTRACT FROM AUTHOR]

Background: The performance of small diameter implantable cardioverter defibrillator (ICD) leads is questionable. However, data on performance during long-term follow-up are scarce. The aim of this study is to provide an update for the lead failure and cardiac perforation rate of Medtronic's Sprint Fidelis ICD lead (Medtronic Inc., Minneapolis, MN, USA) and St. Jude Medical's Riata ICD lead (St. Jude Medical Inc., St. Paul, MN, USA). Methods: Since 1996, all ICD system implantations at the Leiden University Medical Center, the Netherlands, are registered. For this study, data up to February 2011 on 396 Sprint Fidelis leads (follow-up 3.4 ± 1.5 years), 165 8-French (F) Riata leads (follow-up 4.6 ± 2.6 years), and 30 7-F Riata leads (follow-up 2.9 ± 1.3 years) were compared with a benchmark cohort of 1,602 ICD leads (follow-up 3.4 ± 2.7 years) and assessed for the occurrence of lead failure and cardiac perforation. Results: During follow-up, the yearly lead failure rate of the Sprint Fidelis lead, 7-F Riata lead, 8-F Riata lead, and the benchmark cohort was 3.54%, 2.28%, 0.78%, and 1.14%, respectively. In comparison to the benchmark cohort, the adjusted hazard ratio of lead failure was 3.7 (95% confidence interval [CI] 2.4-5.7, P < 0.001) for the Sprint Fidelis lead and 4.2 (95% CI 1.0-18.0, P < 0.05) for the 7-F Riata lead. One cardiac perforation was observed (3.3%) in the 7-F Riata group versus none in the 8-F Riata and Sprint Fidelis lead population. Conclusion: The current update demonstrates that the risk of lead failure during long-term follow-up is significantly increased for both the Sprint Fidelis and the 7-F Riata lead in comparison to the benchmark cohort. Only one cardiac perforation occurred. (PACE 2012; 35:652-658) [ABSTRACT FROM AUTHOR]

ICD Replacement After a Therapy-Free First Service-Life. Introduction: In primary prevention implantable cardioverter defibrillator (ICD) patients, the relatively low incidence of ventricular arrhythmias (VA) combined with the limited battery service-life potentially results in a large group of patients who have had no benefit of the ICD during first service-life. Data on the occurrence of VA after device replacement remain scarce. The purpose of this study was to give clinicians better insight in the dilemma whether or not to replace an ICD after an event-free first battery service-life. Methods and Results: All patients treated with an ICD for primary prevention who had a replacement because of battery depletion and who did not receive appropriate therapy before device replacement were included in this analysis. Of 154 primary prevention ICD patients needing replacement because of battery depletion, 114 (74%) patients (mean age 61 ± 11 years, 80% male) had not received appropriate ICD therapy for VA. Follow-up was 71 ± 24 months after the initial implantation and 25 ± 21 months after device replacement. Following replacement, 3-year cumulative incidence of appropriate therapy in response to ventricular tachycardia or ventricular fibrillation was 14% (95% CI 5-22%). Conclusion: The majority of primary prevention ICD patients do not experience VA during first battery service-life. However, a substantial part of these patients does experience appropriate ICD therapy after replacement. (J Cardiovasc Electrophysiol, Vol. 22, pp. 1346-1350, December 2011) [ABSTRACT FROM AUTHOR]

Aims Changes in left ventricular (LV) diastolic function after cardiac resynchronization therapy (CRT) in relation to LV reverse remodelling and heart failure aetiology have not been extensively characterized. The aims of the study were to evaluate changes in LV diastolic function with speckle-tracking echocardiography in relation to: (i) cardiac resynchronization therapy response (LV remodelling) and (ii) heart failure aetiology. Methods and results A total of 192 heart failure patients undergoing CRT implantation were evaluated. Speckle-tracking echocardiography was performed before and 6 months after implantation and reliable analysis was obtained in 188 patients. Left ventricular diastolic function was assessed by measuring diastolic strain rate during the isovolumic relaxation period (SRIVR) and by calculating the ratio of peak transmitral E-wave to SRIVR (E/SRIVR). Changes in LV diastolic parameters were evaluated in responders and non-responders and in patients with ischaemic and non-ischaemic cardiomyopathy. Response to CRT was defined as ≥15% reduction in LV end-systolic volume at 6 months follow-up. One-hundred and nine patients (58%) were defined as responders. Significant improvements in LV diastolic performance were observed in responders with improvement in SRIVR (from 0.14 ± 0.08 to 0.18 ± 0.12 s−1, P= 0.001) and E/SRIVR (from 834 ± 840 to 641 ± 612, P= 0.04). In addition, LV relaxation improved in patients with non-ischaemic aetiology (SRIVR: from 0.15 ± 0.08 to 0.19 ± 0.13 s−1, P= 0.004). In contrast, LV relaxation did not improve in non-responders and in patients with ischaemic heart disease. Conclusions Novel diastolic strain rate indices are useful for evaluating changes in LV diastolic function after CRT. Improvement in diastolic function was only observed in responders to CRT and patients with non-ischaemic aetiology. [ABSTRACT FROM AUTHOR]

Background: Despite beneficial effects of implantable cardioverter-defibrillator (ICD) therapy, limited service life results in replacement within the majority of patients. Data concerning the effect of replacement procedures on the occurrence of pocket-related adverse events are scarce. In this study, the requirement for pocket-related surgical re-interventions following ICD treatment and the effect of device replacement were evaluated. Methods: From 1992 to 2008, 2,415 patients receiving an ICD at the Leiden University Medical Center were analyzed. Pocket-related complications requiring surgical re-intervention following ICD implantation or replacement were noted. Elective device replacement, lead failure, and device malfunction were not considered pocket-related complications. Results: A total of 3,161 ICDs were included in the analysis. In total, 145 surgical re-interventions were required in 122 (3.9%) ICDs implanted in 114 (4.7%) unique patients. Three-year cumulative incidence for first surgical re-intervention in all ICDs was 4.7% (95% confidence interval [CI] 3.9–5.5%). Replacement ICDs exhibited a doubled requirement for surgical re-intervention (rate ratio 2.2, 95% CI 1.5–3.0). Compared to first implanted ICDs, the occurrence of surgical re-intervention in replacements was 2.5 (95% CI 1.6–3.7) times higher for infectious and 1.7 (95% CI 0.9–3.0) for noninfectious causes. Subdivision by the number of ICD replacements showed an increase in the annual risk for surgical re-intervention, ranging from 1.5% (95% CI 1.2–1.9%) for the first, to 8.1% (95% CI 1.7–18.3%) for the fourth implanted ICD. Conclusions: ICD replacement is associated with a doubled risk for pocket-related surgical re-interventions. Furthermore, the need for re-intervention increases with every consecutive replacement. (PACE 2010; 1013–1019) [ABSTRACT FROM AUTHOR]

Background: The Medtronic Sprint Fidelis (SF) implantable cardioverter defibrillator (ICD; Medtronic Inc., Minneapolis, MN, USA) lead has a higher than expected failure rate. Because of patient safety, Medtronic announced two advisories consisting of (1) adjustments in device settings (October 2007) and (2) installation of a lead integrity algorithm (May 2008). The objective of this study was to evaluate the effect of Medtronic's announcements on patient safety. Methods: To comply with the advisories, two clinical evaluations were conducted. The effect of the advisories was assessed by the lead failure rate and the occurrence of inappropriate shocks due to lead failure. Three periods were distinguished in the comparison of event rates: lead implantation to advisory 1 (period A), in-between both advisories (period B), and advisory 2 to follow-up (period C). Results: Since 2004, 372 patients received a Medtronic ICD and SF lead and were followed from first implant (December 2004) to April 2009. Cumulative incidence rate of lead failure was 3.6%[95% confidence interval (CI) 1.6–5.6] at 21 months and increased to 11.0% (95% CI 6.1–15.9) at 42 months. After implementation of both advisories, the occurrence of inappropriate shocks due to lead failure decreased from 1.5 (95% CI 0.59, 3.00) per 100 lead-years in period A to 0.8 (95% CI 0.02, 4.25) per 100 lead-years in period C. Conclusion: The current study demonstrates that despite an increasing risk for SF lead failure, implementation of the advisories decreased the occurrence of inappropriate shocks due to lead failure. (PACE 2010; 431–436) [ABSTRACT FROM AUTHOR]

Background: Besides implantation of an implantable cardioverter-defibrillator (ICD), a proportion of patients with left ventricular (LV) dysfunction due to ischemic cardiomyopathy are potential candidates for surgical LV reconstruction (Dor procedure), which changes LV ejection fraction (LVEF) considerably. In these patients, LVEF as selection criterium for ICD implantation may be difficult. This study aimed to determine the value of LVEF as criterium for ICD implantation in heart failure patients undergoing surgical LV reconstruction. Methods: Consecutive patients with end-stage heart failure who underwent ICD implantation and LV reconstruction were evaluated. During admission, two-dimensional (2D) echocardiography (LV volumes and LVEF) was performed before surgery and was repeated at 3 months after surgery. Over a median follow-up of 18 months, the incidence of ICD therapy was evaluated. Results: The study population consisted of 37 patients (59 ± 11 years). At baseline, mean LVEF was 23 ± 5%. Mean left ventricular end-systolic volume (LVESV) and left ventricular end-diastolic volume (LVEDV) were 175 ± 73 mL and 225 ± 88 mL, respectively. At 3-month follow-up, mean LVEF was 41 ± 9% (P < 0.0001 vs. baseline), and mean LVESV and LVEDV were 108 ± 65 mL and 176 ± 73 mL, respectively (P < 0.0001 vs. baseline). During 18-month follow-up, 12 (32%) patients had ventricular arrhythmias, resulting in appropriate ICD therapy. No significant relations existed between baseline LVEF (P = 0.77), LVEF at 3-month follow-up (P = 0.34), change in LVEF from baseline to 3-month follow-up (P = 0.28), and the occurrence of ICD therapy during 18-month follow-up. Conclusion: LVEF before and after surgical LV reconstruction is of limited use as criterium for ICD implantation in patients with end-stage heart failure. [ABSTRACT FROM AUTHOR]

Introduction: Diagnosis of arrhythmogenic right ventricular dysplasia/cardiomyopathy (ARVD/C) is based on a set of criteria proposed by the International Task Force (TF) for Cardiomyopathies in 1994. To fulfill these criteria, presence of both electrocardiographic and anatomical abnormalities must be assessed with ECG and imaging techniques, respectively. This may be difficult in patients with early/mild forms of the disease as detectable structural abnormalities may still be absent. We evaluated in which patients presenting with right ventricular tachycardia (VT) serial reevaluation for ARVD/C is indicated. Methods and Results: Sixty consecutive patients (41 men, mean age 40±15 years) were evaluated by the TF criteria for possible ARVD/C because of presentation with a left bundle branch block (LBBB) VT, representing 1 minor criterion. The presence on the ECG of a T-wave inversion beyond lead V2 (1 minor), right precordial QRS prolongation (1 major), or an epsilon wave (1 major) was assessed together with the visualization of severe regional/global right ventricle dysfunction (1 major) or mild segmental dilatation/regional hypokinesia (1 minor) by standard imaging techniques. Initially, 22 (37%) patients were diagnosed as having ARVD/C. After 47±39 (range 6–146) months, 23 initially TF-negative patients were reevaluated because of recurrent symptoms, with 12 (52%) additional patients now meeting the TF criteria. Eleven of these 12 (92%) patients presented initially with ECG abnormalities only, but developed structural abnormalities on imaging at follow-up. Conclusion: ECG abnormalities may precede structural abnormalities warranting serial reevaluation for ARVD/C in initially TF-negative patients presenting with LBBB VT with only ECG abnormalities. [ABSTRACT FROM AUTHOR]

Objective: Evaluation of the relation between clinical characteristics and incidence of recurrent ventricular arrhythmias (VAs) or death during long-term follow-up in a cohort of 300 consecutive ischemic heart disease (IHD) patients who had survived an episode of sudden cardiac arrest (SCA). Background: Survivors of life-threatening VA are at high risk for recurrent events. Methods: A total of 300 consecutive survivors of SCA with IHD were included in a standardized screening and evaluation protocol. Multivariable Cox regression analysis was performed to determine the relation between clinical variables at baseline and the incidence of recurrent VA, all-cause mortality and the composite of both (composite endpoint). Results: The presenting arrhythmia was VT in 156 (52%) patients and VF in 144 (48%) patients. Revascularization was performed in 78 (26%) patients and an ICD was implanted in 216 (72%) patients. During follow-up (mean 30 ± 21 months) 37 (12%) patients died and 88 (29%) patients experienced a recurrence. Advanced age (adjusted hazard ratio (HR) 2.0; 1.2–3.3), history of heart failure (HR 1.8; 1.2–2.6), and amiodarone use (HR 3.1; 2.1–4.6) were independent predictors for the composite endpoint. VT as presenting arrhythmia was an independent predictor for all-cause mortality only (HR 2.4; 1.2–4.8). A decreased risk of recurrences was determined by beta-blocker use (HR 0.5; 0.4–0.8) and coronary revascularization (HR 0.3; 0.2–0.6). Conclusion: In a cohort of 300 consecutive survivors of SCA the incidence of recurrent VA and death is dependant on patient age, history of heart failure, and use of amiodarone. In contrast, use of beta-blockers and aggressive coronary revascularization improve the outcome. [ABSTRACT FROM AUTHOR]

Long-Term Follow-Up of Cardiac Resynchronization Therapy . Introduction: Cardiac resynchronization therapy (CRT) has been introduced to treat patients with end-stage heart failure, and results of this technique are promising. The aim of our study was to assess the sustained benefit of CRT in a large patient cohort with end-stage heart failure at long-term follow-up. In addition, the prognosis of responders and nonresponders was evaluated. Methods and Results: 125 patients with end-stage heart failure, NYHA class III or IV, LVEF <35%, QRS duration >120 msec and left bundle branch block morphology received a biventricular device. At baseline and 6 months after implantation the following parameters were evaluated: NYHA class, Minnesota Quality of life score, QRS duration on surface ECG, 6-minute walking distance and LVEF. Follow-up was obtained up to 3 years. After 6 months, patients were divided in clinical responders and nonresponders according to improvement in NYHA class. All clinical parameters improved significantly at 6-month follow-up. Hospitalization for heart failure was 3.8 ± 4.9 days/year before and 0.7 ± 1.6 days/year after CRT. Survival at 1-, 2-, and 3-year follow-up was 93%, 88%, and 85%, respectively. Responders (78%) showed a significantly better survival than nonresponders at 2- and 3-year follow-up (96% and 93% for responders versus 81% and 73% for nonresponders, P < 0.05). Conclusion: The improvement in functional status and symptoms after CRT is maintained at long-term follow-up (up to 3 years). The clinical improvement was associated with a significant reduction in hospitalization rate which was also maintained over the years. Preimplantation selection of responders may result in even better long-term survival. (J Cardiovasc Electrophysiol, Vol. 16, pp. 1-7, July 2005) [ABSTRACT FROM AUTHOR]

Introduction: Radiofrequency ablation (RFCA) of ventricular tachycardia (VT) is a potential curative treatment modality. We evaluated the results of RFCA in patients with VT. Methods and Results: One hundred fifty-one consecutive patients (122 men and 29 women; age 57 ± 16 years) with drug-refractory VT were treated. Underlying heart disease was ischemic heart disease in 89 (59%), arrhythmogenic right ventricular cardiomyopathy (ARVC) in 32 (21%), and idiopathic VT in 30 (20%; left ventricle in 9 [30%]; right ventricle in 21 [70%]). Ablation was performed using standard ablation techniques. Three hundred six different VTs were treated (cycle length 334 ± 87 msec, 2.0 ± 1.4 VTs per patient). Procedural success (noninducibility of VT after RFCA) was achieved in 126 (83%) patients (70 ischemic heart disease [79%]; 28 ARVC [88%]; 27 idiopathic VT [93%]). Procedure-related complications (<48 hours) occurred in 11 (7%) patients: death 3 (2.0%), cerebrovascular accident 2 (1.3%), complete heart block 4 (2.6%), and pericardial effusion 3 (2.0%). Thirty-three (22%) patients received an implantable cardioverter defibrillator (because of hemodynamic unstable VT, failure of the procedure, or aborted sudden death). During follow-up (34 ± 11 months), VT recurrences occurred in 38 (26%) patients (recurrence rate: 19% in successfully ablated patients and 64% in nonsuccessfully ablated patients; P < 0.001). During follow-up, 12 (8%) patients died (heart failure 8, unknown cause 1, noncardiac cause 3). Conclusion: RFCA of VT can he performed with a high degree of success (83%). The long-term outcome of successfully ablated patients is promising, with a 75% relative risk reduction compared with nonsuccessfully ablated patients. During follow-up, only one patient died suddenly, supporting a selective ICD placement approach in patients with hemodynamically stable VT. [ABSTRACT FROM AUTHOR]