Prevalence and persistence of depression in patients with implantable cardioverter defibrillator: a 2-year longitudinal study

Background: It is unclear whether depression persists in patients with implantable cardioverter defibrillators (ICDs). We evaluated the prevalence and persistence of depression in ICD patients over a 2‐year period. Methods: The study included 90 consecutively hospitalized patients. Patients underlying heart disease was 24% coronary artery disease, 29% idiopathic dilated cardiomyopathy, 24% hypertrophic cardiomyopathy, 13% idiopathic VF/long QT syndrome and miscellaneous conditions 11%. A secondary indication for ICD implantation was present in 20 patients. All patients completed the Zung Self‐Rating Depression Scale (SDS) at study baseline and at the their routine follow‐up visit 2 years after the baseline questionnaire. Delivery of ICD therapies was tracked throughout the 2 years. Results: Depression, indicated by a Zung SDS index score exceeding 60, was present in 29 (32%) of patients at study baseline. Depression was present in 11/51 (21%) patients scheduled to undergo ICD implantation, 2/2 (100%) patients whose device was upgraded to a CRT‐D, 3/14 (21%) patients who had undergone pulse generator replacement, 7/14 (50%) patients who experienced electrical storm and 6/9 (66%) patients hospitalized with acute decompensated heart failure. NYHA functional class III was significantly associated with depression at baseline (HR 6.7, 95% CI 1.68–27.2, p = 0.0007). No differences were noted for female gender, demographics, β‐blocker use, or LVEF ≤35% (p = ns). Depression was present in 25 (28%) of patients at 2 years follow‐up, persisting in 21 (72%) of patients whose Zung SDS scores were elevated at baseline. The median time from ICD shock therapy to completion of the 2 year questionnaire was 9 months (range, 1–22). Patients who were depressed (9/25, 36%) experienced more shocks than non‐depressed patients (6/65, 9%) after 2 years (p = 0.002). Conclusions: Depression is not uncommon among patients who meet criteria for ICD implantation and persists over time particularly when functional status is impaired. Depression is associated with a higher incidence shock therapy. (PACE 2010; 33:1455–1461)     

Phantom shocks in patients with an implantable cardioverter defibrillator

Phantom shock is the sensation of shock in the absence of an actual implantable cardioverter-defibrillator (ICD) discharge. The ICD is now the first-line therapy for patients with ventricular tachycardia and fibrillation. There has been a significant increase in the number of patients with an ICD and patients presenting to the Emergency Department (ED) after a shock for evaluation and device interrogation. Phantom shock is more likely to be nocturnal in the first 6 months after implantation, and patients are more likely to be clinically depressed and have higher levels of anxiety. There is no specific treatment. We report 3 patients who presented to the ED with the sensation of ICD discharges, however, on device interrogation had no shocks and no dysrhythmias.     

Urgent implantable cardioverter defibrillator deactivation by unconventional means

Increasing numbers of patients are receiving implantable cardioverter defibrillators (ICDs); the devices remain fully functional in most terminally ill patients at the time of death. We describe a case of a terminally ill patient with repeated defibrillations who requested urgent ICD deactivation. Nonmedical magnets available in the facility were used to deactivate the ICD and terminate the defibrillations. We then studied various magnetic field sources commonly available in homes, such as ceramic magnets, cell phones, computer hard drives, headsets, and earbuds that potentially may be used to temporarily deactivate an ICD until a device technician is available for reprogramming. We conclude that commonly available magnetic sources may potentially be used to deactivate an ICD. The clinical usefulness of this is speculative and limited to conditions when the need to turn off the device is urgent, and a delay in reprogramming is anticipated.     

Measurement of patient fears about implantable cardioverter defibrillator shock: an initial evaluation of the Florida Shock Anxiety Scale

BACKGROUND: Psychological distress is both a precipitant and a consequence of ICD shock. Therefore, the assessment of patient anxiety and concerns related to receiving an ICD shock may prompt appropriate psychological referrals and treatment. METHODS: The purpose of this study is to assess the initial validity and clinical utility of the Florida Shock Anxiety Scale (FSAS). Seventy-two ICD recipients completed the FSAS. RESULTS: Exploratory factor analysis revealed a two-factor structure with items loading such that Factor 1 could be conceptualized as a Consequence Factor (e.g., fearing creating a scene if the device were to fire) and Factor 2 as a Trigger Factor (e.g., fearing sexual activity). Alpha coefficients suggest good reliability (Cronbach's alpha= 0.91, split-half = 0.92), and FSAS Total Score was moderately correlated (r =-0.65) with total score on the Multidimensional Fear of Death Scale. CONCLUSIONS: Two subscales, labeled consequence of shock and trigger of shock, were established via factor analysis. Collectively the FSAS demonstrates potential utility to assess shock distress and warrants additional investigation.     

Inappropriate detection and therapy from an implantable cardioverter defibrillator due to atrial undersensing

We present a case of inappropriate detection and therapy in a patient with an implantable cardioverter defibrillator. The device interpreted a supraventricular tachycardia as ventricular tachycardia due to unsensed P waves as a result of a relatively high level of atrial sensitivity setting. Subsequently, inappropriate therapy was delivered. The problem was resolved by decreasing the atrial sensitivity value.     

Complications of implantable cardioverter defibrillator therapy in 440 consecutive patients

BACKGROUND: Although more than 150,000 implantable cardioverter defibrillators (ICDs) are implanted yearly worldwide, only few studies systematically examined complications of ICD therapy in large patient cohorts. METHODS: We prospectively analyzed ICD-related complications in 440 consecutive patients who underwent first implantation of an ICD system for primary or secondary prevention of sudden cardiac death within the last 10 years at our institution. All study patients received pectoral nonthoracotomy ICD lead systems with the exception of one patient who had an artificial tricuspid valve. RESULTS: During 46 +/- 37 months follow-up, 136 of 440 patients (31%) experienced at least one complication including implant procedure-related complications in 43 patients (10%), ICD generator-related complications in 28 patients (6%), lead-related complications in 52 patients (12%), and inappropriate shocks in 54 patients (12%). The most serious complications included one perioperative death due to heart failure (0.2%), two ICD system infections necessitating device removal (0.5%) and two perioperative cerebrovascular strokes (0.5%). CONCLUSIONS: We conclude that more than one quarter of ICD patients experience complications during a mean follow-up of almost 4 years, although serious complications such as intraoperative death or ICD system infections are rare in patients with nonthoracotomy ICD systems. Recognition of these complications is the prerequisite for advances in ICD technology and management strategies to avoid their recurrence.     

Inappropriate tachycardia detection by a biventricular implantable cardioverter defibrillator

This case describes "double counting" of intrinsic conduction due to the combination of intraventricular conduction delay and the merging of the electrograms from the right and left ventricle (coronary sinus) leads in a biventricular cardioverter defibrillator. This situation prompted asymptomatic antitachycardia pacing. Lengthening of AV conduction by betablocker solved the problem.     

Inappropriate sensing of pectoral myopotentials by an implantable cardioverter defibrillator system

A case of inappropriate detection of pectoral myopotentials by an implantable cardioverter defibrillator (ICD) system due to inadvertent reversal of the high voltage pins in the ICD header is reported. Inappropriate high voltage connections can result in malfunction of both sensing and defibrillation functions of some ICDs.     

Hyperkalemia diagnosed by implantable cardioverter defibrillator T wave sensing

A patient with congestive heart failure and an ICD had undergone atrioventricular nodal ablation and optimization of heart failure medical therapy. Intracardiac T wave sensing by the ICD drew attention to the new development of asymptomatic hyperkalemia. Surface ECG features of hyperkalemia were not readily identified due to pacemaker dependence.     

Effect of depression on mortality in implantable cardioverter defibrillator recipients--findings from the prospective LICAD study

Introduction: Depression predicts mortality in patients with coronary artery disease and heart failure. However, its effect on patient outcome in the presence of an implantable cardioverter defibrillator (ICD) has not been investigated. Methods: A total of 236 ICD patients (76 females, 58.6 ± 14.0 years) were screened for depressive symptoms using the Hospital Anxiety and Depression Scale (HADS). The outcome measure was all‐cause mortality and the prognostic effect of depression was evaluated with Cox proportional hazards regression analysis. Results: Fifty (21%) patients reported depressive symptoms (HADS score ≥ 8). Renal failure (odds ratio [OR]= 4.0, 95% confidence intervals [CI]= 1.47–10.87, P = 0.007), prior angina (OR = 2.1, 95% CI = 1.07–4.12, P = 0.03), but not the experience of ICD shocks were associated with baseline depressive symptoms. In a mean follow‐up period of 6.1 ± 2.5 years, 74 patients (31%) died. Mortality significantly increased from 45.1 deaths per 1,000 person‐years among patients without depression to 80.3 deaths per 1,000 person‐years in patients with depressive symptoms (P = 0.039). In the univariate model, depression (HADS score ≥8) was a significant predictor of mortality (OR = 1.81, 95% CI = 1.1–3.0, P = 0.02). However, in the multivariate model, depression lost its prognostic significance. Conclusions: In our prospective patient cohort, one‐fifth of ICD recipients reported depressive symptoms. Depression increased the absolute mortality risk but was not an independent predictor of mortality. (PACE 2011; 34:991–997)     

Depression and anxiety status of patients with implantable cardioverter defibrillator and precipitating factors

BACKGROUND: Implantable cardioverter defibrillators (ICDs) are life-saving devices in treatment of life-threatening arrhythmia. We evaluate the emotional status of Turkish patients with ICD and try to explain factors that affect emotional status of the patients. METHODS: Ninety-one patients with previously implanted ICD were included in the study. Follow-up periods, presence of ICD shock, shock frequency, time of the recent shock, age, and gender were noted. Depression and anxiety scores were evaluated according to Hospital Anxiety and Depression (HAD) chart. RESULTS: Mean anxiety and depression scores were found as 9.1 +/- 5.3 and 7.2 +/- 5.1, respectively. According to HAD charts, 42 patients (46%) had anxiety and 37 patients (41%) had depression. Depression scores indicated significant difference between subgroups divided on the basis of follow-up periods (P = 0.026) and on the basis of time of recent shock (P = 0.028). There was significant difference in anxiety scores (P = 0.016) between patients with ICD shocks and patients with no shocks. When the patients were divided into subgroups according to shock frequency, both depression (P = 0.024) and anxiety (P = 0.016) scores presented significant difference. In female patients, depression and anxiety scores were found significantly higher compared to male patients (P = 0.046 and P = 0.016, respectively). In multivariate analysis, gender and shock frequency were found as predictors for anxiety scores (P = 0.019 and P = 0.044, respectively). However same analysis revealed no predictive factor for depression score. CONCLUSION: Our study indicates presence of depression and anxiety in nearly half of the patients with ICD. Consultation with psychiatry should be a part of the treatment for patients with ICD, especially for those who constitute high-risk groups.     

Prospective survey of implantable defibrillator shock anxiety in Japanese patients: Results from the DEF‐Chiba study

Background

Patient‐reported outcomes of implantable cardioverter defibrillator (ICD), such as those with shock anxiety, have emerged as important endpoints that are related to quality of life (QOL), but they have not been well studied in a sample of the Japanese population. Therefore, we prospectively examined changes in shock anxiety in a large sample of Japanese patients with an ICD.

Methods

We recruited 214 consecutive patients with an ICD who visited the outpatient clinic. At registration and 12 months later, all patients completed the Florida Shock Anxiety Scale (FSAS) questionnaire to allow us to examine changes in shock anxiety over the course of the first year after registration.

Results

During the 12‐month follow‐up period, 10.5% of the patients received ICD shock therapy. Female sex, secondary prevention, and experience of ICD shock therapy were associated with high FSAS scores at registration. The FSAS scores in both patients with appropriate and inappropriate shock were significantly higher at the 12‐month follow‐up interval than at registration, and there was no significant difference in the extent of changes in FSAS scores (Δ = 5.2 ± 5.1 and Δ = 6.3 ± 9.9, respectively, P  = 0.62).

Conclusions

Female sex, secondary prevention, and experience of ICD shock therapy are important risk factors affecting shock anxiety in Japanese patients. Attention should be paid to the after‐effects of ICD shock in these patients, regardless of the shock type, with particular attention to women and patients who require secondary prevention.

     

Right pneumothorax resulting from an endocardial screw-in atrial lead in an implantable cardioverter defibrillator system

This report describes a rare case of a patient undergoing implantation of a cardioverter defibrillator in whom a right pneumothorax resulting from an endocardial screw-in atrial lead was observed. Pericardial effusion, substantial changes in lead impedance, andpacing and sensing thresholds were not observed. Pneumothorax disappeared spontaneously and has not reoccurred during follow-up with conservative therapy alone.     

Functional similarity between electrograms recorded from an implantable cardioverter defibrillator emulator and the surface electrocardiogram

Clinical use of stored electrogram (EGM) configurations currently used in ICDs is limited. The hypothesis that EGMs recorded from electrodes on the ICD surface may improve diagnostic capabilities of the device was tested in the present study. The Buttons on Active Can Emulator (BACE), an ICD-sized device containing four button electrodes, was temporarily placed into a subcutaneous or submuscular left pectoral pocket in 16 patients during ICD implantation. Simultaneous recordings were obtained from the ECG lead II, bipolar EGMs using BACE electrodes, and a bipolar atrial EGM during sinus rhythm (SR), ventricular pacing (VP) at cycle lengths of 500 and 400 ms, and VT. Visible P waves were present in all patients during SR (n = 15), in 5 (33%) of 15 patients during VP, and none of the patients during VT (n = 4) using BACE EGMs and lead II. P and QRS amplitudes and the P:QRS ratio during SR in BACE EGMs were significantly lower than those in lead II. BACE EGMs showed prominent changes in QRS morphology and duration during VP and VT compared to SR, and the magnitude of QRS prolongation during VP was similar to that in lead II. Measurements of PR, QRS, and QT duration during SR showed good agreement between BACE EGMs and lead II. In conclusion, EGMs recorded from electrodes embedded on the ICD housing may potentially improve visual discrimination between supraventricular and ventricular arrhythmias. They also may be useful as a surrogate of the ECG for analysis and monitoring of different components of P-QRS-T complex.     

R wave undersensing caused by an algorithm intended to enhance sensing specificity in an implantable cardioverter defibrillator

This article reports on a case of ventricular undersensing despite normal R wave amplitudes during sinus rhythm in an ICD patient. Undersensing of ventricular signals was noted without any evidence of lead dislocation or variation in signal amplitude. Undersensing was due to an exceptionally small R wave signal width and a feature of the Biotronik sensing algorithm designed to avoid oversensing. This algorithm, intended to enhance the sensing specificity of the device, requires registration of two consecutive points above the maximum programmed sensitivity for a ventricular sense event. After modifying the algorithm to a single point registration undersensing disappeared.     

Young at heart: understanding the unique psychosocial adjustment of young implantable cardioverter defibrillator recipients

This article reviews the data related to psychosocial adjustment of young ICD recipients, postulates theories to explain potential adjustment difficulties to ICD therapy experienced by younger recipients, and suggests clinical management techniques for addressing the unique psychosocial concerns of young ICD recipients. Studies of young ICD recipients suggest that a wide range of psychosocial adjustment issues are prominent in the post-ICD implantation period and that the issues may be different from older ICD recipients. The disability-stress-coping model and the transactional-stress-coping model are postulated as explanations for the unique adjustment concerns of children and adolescents with ICDs. Social comparison theory is also applied to the concerns of young adults with ICDs such that they often lack same age peers to compare experiences with cardiac difficulties. Brief, clinic-based interventions by health care providers, like a screening and referral heuristic and an "ICD Buddy" system, are suggested to increase effective coping and decrease social isolation for young ICD recipients.