Efficacy of implantable cardioverter defibrillator therapy for primary and secondary prevention of sudden cardiac death in hypertrophic cardiomyopathy

Risk stratification and effectiveness of implantable cardioverter-defibrillator (ICD) therapy are unresolved issues in hypertrophic cardiomyopathy (HCM), a cardiac disease that is associated with arrhythmias and sudden death. We assessed ICD therapy in 132 patients with HCM: age at implantation was 34 +/- 17 years, and 44 (33%) patients were aged 相似文献   

Patient understanding of disease and the use and outcome of implantable cardioverter defibrillators in hypertrophic cardiomyopathy

Hypertrophic cardiomyopathy (HCM) is the most common cause of sudden cardiac death (SCD) in young individuals. Implantable cardioverter defibrillators (ICD) are the primary therapy for sudden death prevention; however, are associated with both physical and psychological complications. We sought to determine factors associated with ICD understanding and patient satisfaction. This was a cross‐sectional study, using patient/parent answered questionnaires distributed to patients enrolled in the Hypertrophic Cardiomyopathy Association. Patient characteristics and satisfaction data were obtained via questionnaire. Patients were compared based on age at diagnosis and presence of ICD. ICD patients with high satisfaction were compared to those with low satisfaction to determine factors associated with poor satisfaction. A total of 538 responses were obtained (53 ± 16 years); 46% were females. Seventy patients (13%) were diagnosed with HCM < 18 years of age and 356 (66%) had an ICD. Compared to those without an ICD, patients with ICDs were younger at age of diagnosis (P = 0.001) and time of study (P = 0.008). Patients with ICDs were more likely to have presented with syncope and have family history of ICD, SCD, or HCM‐related death. Nineteen patients (5%) felt that issues surrounding their ICD outweighed its benefit. Compared to patients with a favorable satisfaction, the only significant difference was the preimplant ICD discussion (P < 0.001) and history of lead replacement (P = 0.01). In conclusion, the majority of HCM patients with ICDs are satisfied with their ICD management and feel the benefits of ICDs outweigh issues associated with ICDs. Additionally, these data highlight the importance of the preimplant patient‐physician discussion around the need for ICD prior to implantation.     

植入型心律转复除颤器在心脏性猝死一级预防中的应用

目的随访观察植入型心律转复除颤器（ICD）／心室再同步心律转复除颤器（CRT．D）在中国单中心心脏性猝死（SCD）高危患者一级预防中的临床应用。方法入选2009年1月至2011年12月入住浙江大学医学院附属第一医院心内科符合一级预防适应证并植入ICD／CRT．D的患者共80例,其中33例植入单腔／双腔ICD,47例植入CRT．D。基础病因主要为扩张性心肌病（55．0％）和冠状动脉性心脏病（27．5％）。植入ICD／CRT．D后第1个月末和第3个月末各随访1次,以后每6个月随访1次,若患者发生电击等ICD治疗事件,则即时进行检查。结果80例患者平均随访（23±7）个月,非计划性再入院11例（13．7％）,死亡4例（5．0％）。记录ICD治疗事件共38次,其中有26次（68．4％）为ICD识别持续性VT／VF发作而进行的适当治疗,12次（31．6％）为由于心房颤动而进行的不适当治疗事件。结论ICD,CRT—D能在短时间内对发生恶性快速性心律失常的患者进行识别及实施治疗,在SCD一级预防中疗效明确,可使SCD的高危患者获益。     

Global longitudinal strain and left atrial volume index improve prediction of appropriate implantable cardioverter defibrillator therapy in hypertrophic cardiomyopathy patients

Accurate predictors of appropriate implantable cardioverter defibrillator (ICD) therapy in hypertrophic cardiomyopathy (HCM) patients are lacking. Both left atrial volume index (LAVI) and global longitudinal strain (GLS) have been proposed as prognostic markers in HCM patients. The specific value of LAVI and GLS to predict appropriate ICD therapy in high-risk HCM patients was studied. LAVI and 2-dimensional speckle tracking-derived GLS were assessed in 92 HCM patients undergoing ICD implantation (69 % men, mean age 50 ± 14 years). During long-term follow-up, appropriate ICD therapies, defined as antitachycardia pacing and/or shock for ventricular arrhythmia, were recorded. Appropriate ICD therapy occurred in 21 patients (23 %) during a median follow-up of 4.7 (2.2–8.2) years. Multivariate analysis revealed LAVI (p = 0.03) and GLS (p = 0.04) to be independent predictors of appropriate ICD therapy. Both LAVI and GLS showed higher accuracy to predict appropriate ICD therapy compared to presence of ≥1 conventional sudden cardiac death (SCD) risk factor(s) [area under the curve 0.76 (95 % CI 0.65–0.87) and 0.65 (95 % CI 0.54–0.77) versus 0.52 (95 % CI 0.43–0.58) respectively, p < 0.001]. No patient with both LAVI <34 mL/m² and GLS <?14 % experienced appropriate ICD therapy. Assessment of both LAVI and GLS on top of conventional SCD risk factors provided incremental clinical predictive value for appropriate ICD therapy, as shown by likelihood ratio test (p < 0.001) and integrated discrimination improvement index (0.17, p < 0.001). LAVI and GLS provide high negative predictive value for appropriate ICD therapy in high-risk HCM patients. Additionally to conventional SCD risk factors, both parameters may be useful to optimize criteria and timing for ICD implantation in these patients.     

Right Ventricular Dysfunction and the Incidence of Implantable Cardioverter‐Defibrillator Therapies

Introduction: Implantable cardioverter‐defibrillator (ICD) therapy is well established in preventing sudden cardiac death in patients with left ventricular dysfunction. The influence of right ventricular (RV) function on ICD therapy for sudden cardiac death (SCD) is not known. Methods: We retrospectively studied 222 patients receiving an ICD for primary prevention of SCD. Baseline clinical and echocardiographic data were gathered. RV systolic function was qualitatively assessed as normal or abnormal (described as mildly, moderately, or severely reduced). Primary endpoint was combined ICD therapy or death and secondary endpoint was ICD therapy alone. Results: The mean follow‐up was 940 ± 522 days. The mean left ventricular ejection fraction was 0.23 ± 0.07. By Kaplan‐Meier analysis, RV dysfunction was predictive of combined ICD therapy or death when comparing between normal and abnormal RV function (P = 0.008) and among qualitative ranges of RV function (P = 0.012). RV dysfunction was not predictive of ICD therapy alone with either type of classification. After adjusting for clinical covariates, severe RV dysfunction was predictive of the combined endpoint of ICD therapy or death (HR 2.02, 95% CI 1.04–3.92, P = 0.037). Conclusion: Severe RV dysfunction appears to be an independent predictor of the combined endpoint of ICD therapy or death. RV dysfunction does not reliably predict the incidence of ICD therapy alone.     

The clinical challenge of preventing sudden cardiac death immediately after acute ST-elevation myocardial infarction

Unfortunately, of all patients experiencing acute myocardial infarction (MI), usually in the form of ST-elevation MI, 25–35% will die of sudden cardiac death (SCD) before receiving medical attention, most often from ventricular fibrillation. For patients who reach the hospital, prognosis is considerably better and has improved over the years. Reperfusion therapy, best attained with primary percutaneous coronary intervention compared to thrombolysis, has made a big difference in reducing the risk of SCD early and late after ST-elevation MI. In-hospital SCD due to ventricular tachyarrhythmias is manageable, with either preventive measures or drugs or electrical cardioversion. There is general agreement for secondary prevention of SCD post-MI with implantation of a cardioverter defibrillator (ICD) when malignant ventricular arrhythmias occur late (>48 h) after an MI, and are not due to reversible or correctable causes. The major challenge remains that of primary prevention, that is, how to prevent SCD during the first 1–3 months after ST-elevation MI for patients who have low left ventricular ejection fraction and are not candidates for an ICD according to current guidelines, due to the results of two studies, which did not show any benefits of early (<40 days after an MI) ICD implantation. Two recent documents may provide direction as to how to bridge the gap for this early post-MI period. Both recommend an electrophysiology study to guide implantation of an ICD, at least for those developing syncope or non-sustained ventricular tachycardia, who have an inducible sustained ventricular tachycardia at the electrophysiology study. An ICD is also recommended for patients with indication for a permanent pacemaker due to bradyarrhythmias, who also meet primary prevention criteria for SCD.     

Implantable Cardioverter Defibrillator Therapy for Primary Prevention of Sudden Cardiac Death after Myocardial Infarction:

Study Objective: To estimate the proportion of patients eligible for implantable cardioverter defibrillator (ICD) therapy for the primary prevention of sudden cardiac death after a myocardial infarction (MI), according to the current guidelines.
Methods: Eligibility was assessed retrospectively at 6 weeks in 513 post-MI survivors (age 66 ± 13 years, left ventricular ejection fraction 48.2 ± 17%) on the basis of an electrocardiogram and an echocardiogram.
Results: LVEF was ≤ 40% in 37% and ≤ 35% in 30%, and QRS duration was <120 ms in 89% and ≥120 ms in 11% of patients. The proportion of post-MI patients meeting the criteria set by guidelines were 37% for 2006 American College of Cardiology/American Heart Association/European Society of Cardiology (ACC/AHA/ESC) 26.5% for 2008 ACC/AHA/Canadian Heart Rhythm Society 16.3% for 2005 US Centers for Medicare and Medicaid Services (CMS), and 5.8% for the 2006 United Kingdom (UK) National Institute of Clinical Excellence (NICE). According to 2005 CMS and 2006 UK-NICE guidelines, Holter monitoring was required in 7% and 18%, respectively. For the United States (700,000 MI in 2006), the 2006 ACC/AHA/ESC guidelines equate to 216,783 ICD implantations/year. For UK (60,499 MI in 2006), the 2006 NICE guidelines equate to 2,941 ICD implantations, 10,488 Holter studies, and 1,065 VT induction tests/year.
Conclusions: Current ICD therapy guidelines for primary prevention of SCD post-MI demand a substantial increase in service provision worldwide.     

Implantable Cardioverter-Defibrillators in Children

Implantable cardioverter-defibrillators (ICD) in adults have shown to be safe and effective for both primary and secondary prevention of sudden cardiac death (SCD). In children and patients with congenital heart disease prospective trials to evaluate the safety and efficacy of these devices are still lacking. This review will discuss the different aspects of ICD therapy in children with regard to current indications, effectiveness, problems related to size and growth, inappropriate shock therapy, and quality of life.     

Ventricular tachyarrhythmias in patients receiving an implantable cardioverter-defibrillator for primary versus secondary prophylaxis indications

Introduction: Data on the mechanisms of sudden cardiac death are limited and may be biased by delays in rhythm recording and selection bias in survivors. As a result, the relative contributions of monomorphic ventricular tachycardia (VT) (cycle length [CL] > 260 ms), monomorphic fast VT (FVT) (CL ≤ 260 ms), and polymorphic VT (PMVT)/ventricular fibrillation (VF) have not been well characterized nor compared in patients with and without prior arrhythmic events. Methods: A retrospective cohort study of implantable cardioverter‐defibrillator (ICD) recipients with primary or secondary implant indications was used to evaluate intracardiac electrograms (EGMs) for the first spontaneous VT/VF resulting in appropriate ICD therapy. EGMs were categorized into VT, FVT, and PMVT/VF based on CL and morphologic criteria. Results: Of 616 implants, 145 patients (58 [40%] primary indications) received appropriate ICD therapy for VT/VF over mean follow‐up of 3.8 ± 3.2 years. Primary implants had more diabetes (28% vs 12%; P = 0.02) and less antiarrhythmic use (15% vs 33%; P = 0.02). In those patients with spontaneous arrhythmia, PMVT/VF occurred in 20.7% of primary versus 21.8% of secondary implants, FVT in 19.0% versus 21.8%, and VT in 60.3% versus 56.4%, respectively (P = 0.88). Spontaneous VT CL was similar regardless of implant indication (284 ± 56 [primary] vs 286 ± 67 ms [secondary]; P = 0.92). Conclusions: Monomorphic VT is the most common cause of appropriate ICD therapy regardless of implant indication. These results provide insight into the mechanisms of sudden cardiac death and have implications for the use of interventions designed to limit ICD shocks. (PACE 2011; 34:571–576)     

The Role of Implantable Cardioverter Defibrillators in Non VT/VF Sudden Deaths

Implantable cardioverter defibrillator (ICD) therapy has been an impressive success in preventing sudden cardiac death (SCD). Electrocardiographic documentation of SCD in ICD patients has been rare, but usually arrhythmias other than ventricular tachycardia/ventricular fibrillation (VT/VF; asystole and electromechanical dissociation [EMD]) have been implicated. This raises the question whether backup bradycardia pacing can prevent deaths due to asystole and EMD in such patients. We studied the outcome of 88 patients with permanent bradycardia pacemakers and compared them to 500 consecutive nonpacemaker patient controls, sustaining out-of-hospital cardiac arrest and undergoing resuscitation by paramedics. Mean age of the pacemaker patients was 73.5 ± 10.3 years and 64% males, compared to mean age of 68.2 ± 6.7 years and 67% males in the control group. Overall success of resuscitation and survival rates were similar. When the documented rhythm was VT/VF or asystole there were no differences in resuscitation or survival rates for the pacemaker or nonpacemaker patients. However, resuscitation rate was significantly higher in pacemaker patients than nonpacemaker patients with EMD: 47% versus 20% ( P < 0.03). For EMD, survival rate for the pacemaker patients was 13% compared to 5% in the nonpacemaker patients, but this difference was not statistically significant. Backup bradycardia pacing in future generation devices may improve the outcome of non VT/VF sudden cardiac death in at least some of the ICD recipients.     

Cardiac defibrillation and resynchronization therapies: principles, therapies, and management implications

Patients with heart failure remain at high risk for sudden cardiac death (SCD) and death due to heart failure progression, despite the incorporation of pharmacologic agents into clinical practice that have been shown to decrease mortality in clinical trials. Most patients experience SCD as their first dysrrhythmic event. The implantable cardioverter defibrillator (ICD) effectively terminates ventricular tachycardia/fibrillation (VT/VF) aborting SCD. Cardiac resynchronization therapy (CRT) complements pharmacologic therapy improving cardiac performance, quality of life, functional status, and exercise capacity in patients with systolic dysfunction despite optimal medical therapy who have a prolonged QRS duration; furthermore, it decreases mortality when compared with optimal medical therapy alone. Implantation of a combination CRT and ICD device, a CRT-D, reduces mortality by aborting SCD and providing the functional benefits of CRT. This article discusses the evolution of CRT-D therapy, the mechanism of operation of a CRT-D device, and nursing implications.     

Sustained polymorphic arrhythmias induced by programmed ventricular stimulation have prognostic value in patients receiving defibrillators

BACKGROUND: Patients with ischemic cardiomyopathy (ICM) who have monomorphic ventricular tachycardia (VT) induced by programmed ventricular stimulation (PVS) are at increased risk of sudden cardiac death (SCD). Among a primary prevention population, the prognostic significance of induced polymorphic ventricular arrhythmias is unknown. METHODS: A total of 105 consecutive patients who received an implantable cardioverter-defibrillator (ICD) for primary prevention of SCD in the setting of ICM and non-sustained VT were retrospectively evaluated. Seventy-five patients (group I) had induction of monomorphic VT and 30 patients (group II) had a sustained ventricular arrhythmia other than monomorphic VT (ventricular flutter, ventricular fibrillation, and polymorphic VT) induced during PVS. RESULTS: Baseline characteristics were similar between group I and group II except for ejection fraction (25% vs. 31%, P = 0.0001) and QRS duration (123 milliseconds vs. 109 milliseconds, P = 0.04). Sixteen of 75 (21.3%) patients in group I and 6 of 30 (20%) patients in group II received appropriate ICD therapy (P = 0.88). Survival free from ICD therapy was similar between groups (P = 0.54). There was a trend toward increased all-cause mortality among patients in group I by Kaplan-Meier analysis (P = 0.08). However, when adjusted for age, EF, and QRS duration mortality was similar (P = 0.45). CONCLUSIONS: There is no difference in rates of appropriate ICD discharge or mortality between patients dichotomized by type of rhythm induced during PVS. These results suggest that patients in this population who have inducible VF or sustained polymorphic VT have similar rates of subsequent clinical ventricular tachyarrhythmias as those with inducible monomorphic VT.     

Scar heterogeneity on cardiovascular magnetic resonance as a predictor of appropriate implantable cardioverter defibrillator therapy

Background

Despite the survival benefit of implantable-cardioverter-defibrillators (ICDs), the vast majority of patients receiving an ICD for primary prevention do not receive ICD therapy. We sought to assess the role of heterogeneous scar area (HSA) identified by late gadolinium enhancement cardiovascular magnetic resonance (LGE-CMR) in predicting appropriate ICD therapy for primary prevention of sudden cardiac death (SCD).

Methods

From September 2003 to March 2011, all patients who underwent primary prevention ICD implantation and had a pre-implantation LGE-CMR were identified. Scar size was determined using thresholds of 4 and 6 standard deviations (SD) above remote normal myocardium; HSA was defined using 3 different criteria; as the region between 2 SD and 4 SD (HSA_2-4SD), between 2SD and 6SD (HSA2-6SD), and between 4SD and 6SD (HSA_4-6SD). The end-point was appropriate ICD therapy.

Results

Out of 40 total patients followed for 25 ± 24 months, 7 had appropriate ICD therapy. Scar size measured by different thresholds was similar in ICD therapy and non-ICD therapy groups (P = NS for all). However, HSA_2-4SD and HSA_4-6SD were significantly larger in the ICD therapy group (P = 0.001 and P = 0.03, respectively). In multivariable model HSA_2-4SD was the only significant independent predictor of ICD therapy (HR = 1.08, 95%CI: 1.00-1.16, P = 0.04). Kaplan-Meier analysis showed that patients with greater HSA_2-4SD had a lower survival free of appropriate ICD therapy (P = 0.026).

Conclusions

In primary prevention ICD implantation, LGE-CMR HSA identifies patients with appropriate ICD therapy. If confirmed in larger series, HSA can be used for risk stratification in primary prevention of SCD.     

Implantable cardioverter-defibrillator in patients with chronic heart failure

Sudden cardiac death (SCD) is a major cause of death in patients with chronic heart failure. The implantable cardioverter-defibrillator (ICD) effectively treats malignant ventricular tachyarrhythmias and reduces significantly the total mortality as well as the incidence of SCD in heart failure patients. It is evident that ICD is indicated for the secondary prevention of SCD. There is growing evidence for the use of the ICD for the primary prevention of SCD in patients with LV systolic dysfunction without documented arrhythmia. However, the efficacy of ICD seems to be modest in patients with advanced heart failure. Individualized combined therapies such as ICD plus amiodarone and ICD plus cardiac resynchronization therapy are necessary for advanced heart failure patients. It is doubtful whether ICD is indicated for MADIT II and SCD -HeFT population in Japan, where the incidence of SCD is thought to be lower than the Western countries.     

Left ventricular apical aneurysm in hypertrophic cardiomyopathy as a risk factor for sudden death at any age

In hypertrophic cardiomyopathy (HCM) aging has proved protective against sudden death (SD) risk and aggressive recommendations for prophylactic ICDs are uncommon in patients ≥60 years. Nevertheless, we present a patient with an unexpected but aborted sudden death event at the advanced age of 71 years due to a left ventricular apical aneurysm (LVAA) which has emerged as a novel SD marker. Subsequent reappraisal of the Tufts HCM database, specifically the 118 LVAA patients, showed that 36% of SD events occurred at ≥60 years. Of HCM patients ≥ 60 years, SD was 8‐fold more common with aneurysm than without aneurysms (16% vs 2%; P < 0.001). Risk in HCM with LVAA persists throughout life and senior LVAA patients should also be considered for primary prevention of SD with the ICD.     

Current perspectives in hypertrophic cardiomyopathy with the focus on patients in the Finnish population: a review

Hypertrophic cardiomyopathy (HCM) is the most common inherited heart disease, with the prevalence of about 1/500. During the last two decades, the knowledge of the etiology, pathogenesis, risk stratification and prevention of sudden death in HCM has substantially advanced. Most often, HCM is familial and caused by mutations in sarcomere genes, inherited in an autosomal dominant manner. In Finland, genetic background of HCM is unique, with a few founder mutations in cardiac sarcomere genes accounting for a considerable proportion of the disease. Pathogenic mechanisms induced by disease-causing mutations are still poorly understood, although alterations in intracellular calcium handling and inefficient generation of contractile force in myocytes are considered key features in triggering the hypertrophic response. Clinical features of the disease are highly variable from no symptoms to the spectrum of exertional dyspnea, angina, palpitations, syncope and sudden death. In the current patient care, implantable cardioverter defibrillators (ICDs) are successfully used to prevent sudden cardiac death in high risk subjects. Targeted genetic testing is recommended to confirm the diagnosis in patients with HCM and to identify family members with the disease. Future research is needed to elucidate key cellular mechanisms leading to HCM, which may allow specific prevention and treatment of the disease.

• Key messages

• Hypertrophic cardiomyopathy, most often caused by defects in sarcomere genes, is the most common inherited heart disease, and a common cause of sudden cardiac death (SCD) in athletes and young subjects.

• Cardiac imaging, ECG and genetic testing are pivotal in the diagnosis of the disease in patients and first-degree relatives.

• Implantable cardioverter defibrillators in patients with high risk for SCD and tailored pharmacotherapy are efficient tools in patient care, but so far, exact mechanisms leading to cardiac hypertrophy in HCM are only partially understood, and there is no curative treatment for the disease.

     

Outcomes of Elderly Recipients of Implantable Cardioverter Defibrillators

Aims of the Study: To examine the patterns of use, complication rates, and survival in elderly recipients of implantable cardioverter defibrillators (ICD).
Methods and Results: We followed 500 consecutive patients included in the Marburg Defibrillator database for 48 ± 39 months. There were 40 patients (8%) ≥75 and 460 (92%) <75 years of age at the time of implant. The 5-year Kaplan-Meier estimate for appropriate treatment of VT or VF by ICD was 49% among patients <75- versus 57% among patients ≥75-years-old (P = 0.17). The 5-year sudden death rate was similarly low in both groups of patients (2% versus 3%). The 5-year overall mortality rate was significantly higher in patients ≥75 than in patients <75 years of age (55% versus 21%, P = 0.001), due to a higher mortality from heart failure (HF). All procedure-related, lead-related, and pulse generator-related complications were similar in both patient groups (23% versus 25%).
Conclusions: ICD therapy was equally effective in patients ≥75 and patients <75 years of age in the prevention of sudden cardiac death. While the complication rates were similar in both age groups, the long-term mortality was considerably higher in elderly patients, due to a higher mortality from HF. The current ICD therapy guidelines appear applicable to elderly patients who are otherwise medically stable and without advanced HF.     

Implantable Cardioverter Defibrillator for Prevention of Sudden Cardiac Deatb in Patients with Ventricular Tachycardia and Ventricular Fibrillation: ICD Therapy In Sudden Cardiac Death

Among the various therapy options for survivors of ventricular tachycardia-ventricular fibrillation (VT-VF), the implantable cardioverter defibrillator (ICD) seems most promising. It reliably terminates VT-VF and thus significantly impacts sudden cardiac death (SCD) survival. It is more effective than any of the known antiarrhythmic drugs in prevention of SCD, particularly among survivors of cardiac arrest. Compared to VT surgery, the ICD therapy can be offered to a larger pool of patients and can be placed at a lower surgical risk. With proper patient selection, ICD therapy is of major benefits to its recipients since it markedly reduces the chances of VT-VF relaled mortality; the main cause of premature death in this population. The ICD therapy is cost effective when compared to other medical interventions and could be more so if the implant is carried out early in the course of VT-VF management.     

Late Gadolinium Enhancement in Patients with Nonischemic Dilated Cardiomyopathy

One‐third of all patients with heart failure have nonischemic dilated cardiomyopathy (NIDM). Five‐year mortality from NIDM is as high as 20% with sudden cardiac death (SCD) as the cause in 30% of the deaths. Currently, the left ventricular ejection fraction (LVEF) is used as the main criteria to risk stratify patients requiring an implantable cardioverter defibrillator (ICD) to prevent SCD. However, LVEF does not necessarily reflect myocardial propensity for electrical instability leading to ventricular tachycardia (VT) or ventricular fibrillation (VF). Due to the differential risk in various subgroups of patients for arrhythmic death, it is important to identify appropriate patients for ICD implantation so that we can optimize healthcare resources and avoid the complications of ICDs in individuals who are unlikely to benefit. We performed a systematic search and review of clinical trials of NIDM and the use of ICDs and cardiac magnetic resonance imaging with late gadolinium enhancement (LGE) for risk stratification. LGE identifies patients with NIDM who are at high risk for SCD and enables optimized patient selection for ICD placement, while the absence of LGE may reduce the need for ICD implantation in patients with NIDM who are at low risk for future VF/VT or SCD.     

Safety and effectiveness of primary prevention cardioverter defibrillators in octogenarians

Background: Implantable cardioverter‐defibrillators (ICDs) reduce the rate of sudden cardiac death (SCD) in patients with cardiomyopathy and reduced left ventricular systolic function. It is unclear if this benefit extends to the very elderly patient population. Methods: Patients who underwent initial ICD implantation at age 80 or older between January 1995 and April 2010 for primary SCD prevention were identified. Clinical data were collected from the medical record, including periprocedural complications, device type, and therapies delivered. Results: Three‐hundred eighty patients were identified; 84 patients met eligibility criteria. The mean age was 82.68 years; mean follow‐up was 34 months. Mean left ventricular ejection fraction was 28.1%. Mortality during follow‐up was 17.9%. One‐ and 5‐year survival estimates were 100% and 60%, respectively. Periprocedural complications occurred in 9.4% of patients; serious complications occurred in 4.8% with no periprocedural deaths. Device therapies occurred in 11.9% (n = 10) of patients (9.5% appropriate, n = 8; 2.4% inappropriate, n = 2). Cardiac resynchronization therapy‐defibrillator (CRT‐D) implantation was associated with prolonged median survival and decreased risk of death (hazard ratio 0.212; 95% confidence interval 0.048?.942, P = 0.042) compared to ICD alone. Conclusions: Implantation of primary prevention ICDs in patients 80 years of age or older was associated with a low risk of serious complications and a 5‐year survival estimate of 60%. Inappropriate therapies after implantation were uncommon. CRT‐D implantation was associated with a decreased risk of death compared to ICD alone. These data suggest that, in selected patients in this age group, ICD implantation is safe and effective. (PACE 2011; 34:900–906)