Psychological indices and phantom shocks in patients with ICD

Understanding Phantom Shocks in Implantable Cardioverter-Defibrillator Recipients

Phantom shocks in implantable cardioverter-defibrillator (ICD) recipients create a complex nexus between cardiac treatment and psychological distress. These sensations, mimicking therapeutic shocks without device activation, deeply affect patients' functionality and well-being. Heightened anxiety, depression, and hopelessness predispose individuals to these occurrences, posing significant challenges. This article delves into the intricate nature of phantom shocks, highlighting subtle clinical cues to differentiate them from genuine therapy shocks. Through a case study of a 75-year-old male with recurrent ICD shocks, diagnosed eventually with phantom shocks, the interplay between psychological distress and physical sensations is underscored. Urgent intervention to address the patient's anxiety and depression using psychotherapy and antidepressants became imperative. The case underscores the immense psychological toll of phantom shocks, exacerbating fear, hopelessness, and post-traumatic stress disorder (PTSD). Despite treatment attempts, their impact persisted, leading to a shift to comfort-focused care. While research identifies factors such as education levels and prior therapy, predicting and managing phantom shocks remains challenging. This article stresses the need for clinician vigilance, urging proactive identification and tailored interventions to mitigate the profound effects of phantom shocks. The current research landscape lacks comprehensive strategies, necessitating further exploration and targeted therapies to restore patient well-being. In conclusion, comprehensive understanding and specialized care for phantom shocks in ICD recipients, addressing both cardiac and psychological aspects, are imperative. Early recognition and tailored interventions offer promise in alleviating their adverse effects, reinstating patient control, and improving their quality of life.

Addressing PTSD in Implantable Cardioverter Defibrillator Patients: State-of-the-Art Management of ICD Shock and PTSD

PURPOSE OF REVIEW

This paper reviews the unique processes and treatments of post-traumatic stress in implantable cardioverter-defibrillator (ICD) patients and posits specific clinical management recommendations.

RECENT FINDINGS

PTSD is a common presenting problem for a prospective ICD patient and is a common response to ICD shocks. Approximately 32% of patients with sudden cardiac arrest report significant PTSD symptoms. Following ICD shock, approximately 20% experience PTSD from the shocks. Regardless, PTSD can interrupt and undermine clinical management from a cardiologist perspective and create significant disturbance in patients and families. Few cardiology clinics are outfitted to effectively manage psychological distress, in general, and PTSD, in particular. Effective management of PTSD patients can be achieved with both direct care in the cardiac clinic, as well as indirect care via multidisciplinary consultation and expertise. The importance of emotional validation, return to physical activity, and family engagement is emphasized in current management.

Impact of ultra-conservative ICD programming in patients with LVADs: Avoiding potentially unnecessary tachy-therapies

BACKGROUND

Patients with left ventricular assist devices (LVAD) often tolerate ventricular arrhythmias (VA). We aim to assess the frequency and outcomes of ICD therapies averted by ultraconservative ICD programming (UCP) in LVAD patients.

METHODS

This single center, retrospective cohort study included patients with LVADs and ICDs implanted from 2015 to 2019 that had UCP. The aim for UCP was to maximally delay VA treatments and maximize anti-tachycardia pacing (ATP) prior to ICD shocks. VA events were reviewed after UCP and evaluated under prior conservative programming to assess for potentially averted events (that would have resulted in either ATP or defibrillation with prior programming).

RESULTS

Fifty patients were included in the study with follow-up of median 16 ± 10.2 months after UCP. The median time from LVAD implantation to reprogramming was 7 days (IQR 5-9 days). Fourteen patients (28%) had potentially averted VA events that would have been treated with their prior ICD programming (82 total events, median two events per patient, IQR 1-10 events). Treated VA events occurred in 15 patients (30%). Eleven of the 14 patients with potentially averted VAs had treated events as well. Only one patient reported definitive symptoms of self-limited "dizziness" during a potentially averted event that did not result in hospitalization. No patients died of complications from or needed emergent care/hospitalization due a potentially averted VA.

CONCLUSIONS

UCP in LVAD patients likely prevented unnecessary VA treatments in many patients with minimal reported symptoms during these potentially averted events. Prospective studies are necessary to confirm these findings.

Phantom shocks in implantable cardioverter-defibrillator recipients: impact of education level, anxiety, and depression

BACKGROUND

Implantable cardioverter defibrillators (ICDs) are designed to deliver shocks in the event of ventricular arrhythmias. Some ICD recipients experience the sensation of ICD discharge in the absence of an actual discharge (phantom shock, PS).

OBJECTIVES

The aim of this study was to evaluate the incidence, predictors, and consequences of PS in ICD recipients.

MATERIALS AND METHODS

Consecutive ICD recipients were examined during a routine outpatient follow-up (FU) visit. Subjects completed a written survey; their level of depression and anxiety was assessed with the hospital anxiety and depression scale (HADS). Quality of life (QOL) was assessed using the Minnesota living with heart failure questionnaire.

RESULTS

Of 434 patients invited to the study, 423 (97.5%) ICD recipients agreed to and completed the survey; 349 (83%) had a primary prevention indication and 339 (80%) ischemic cardiomyopathy. A total of 27 patients (6.4%) reported a PS during a mean FU of 64 ± 44 months (5.4% in the primary prevention group and 10.8% in the secondary prevention group; p = 0.11). PS were related to higher education (≥bachelor's degree 41% versus 20%; p = 0.03), and more frequent in patients receiving adequate shocks during FU (34% versus 0.5%; p < 0.001). HADS score levels were higher following PS (15 ± 6 versus 8.8 ± 7.4; p < 0.001). The majority of patients reporting PS felt that the information provided to them prior to ICD placement was insufficient (22.2% versus 5.0%), that they needed psychological support after ICD implantation (26% versus 3%), and considered ICD deactivation in near end-of-life situations (59% versus 29%; p < 0.001 for all).

CONCLUSIONS

PS occur in 6.4% of all ICD recipients and are related to higher education and to patients that experienced adequate shocks during FU.

Treatment of phantom shocks: A case report

Implantable cardioverter-defibrillators have become standard preventive treatment for patients with ventricular arrhythmias and other life-threatening cardiac conditions. The advantages and efficiency of the device are supported by multiple clinical trials and outcome studies, leading to its popularity among cardiologists. Implantation of the device is not without adverse outcomes. Implantable cardioverter-defibrillator placement has been found to lead to negative psychological and psychosocial sequelae such as apprehension to engage in physical activity, chronic anxiety, decreased physical and social functioning, a nagging fear of being shocked by the device, and the development of "phantom shocks." Defined as patient-reported shocks in the absence of evidence that the implantable cardioverter-defibrillator device has discharged, phantom shocks could impact the mental health of those affected. This article reviews the case of Mr. L, a 47-year-old man with ischemic cardiomyopathy who was seen by the psychiatry consultation team while under cardiologic care because he reported that his implantable cardioverter-defibrillator device had been shocking him despite no objective evidence after interrogating the device. A literature review of phantom shocks, their associated symptomatology, and psychological consequences are outlined and discussed.

Posttraumatic stress disorder and mortality in VA patients with implantable cardioverter-defibrillators

BACKGROUND

The association between posttraumatic stress disorder (PTSD) and mortality in patients undergoing implantable cardioverter-defibrillator (ICD) placement has not been evaluated in US veterans.

HYPOTHESIS

PTSD in veterans with ICD is associated with increased mortality.

METHODS

We studied a retrospective cohort of 25 678 veterans who underwent ICD implantation between September 30, 2002, and December 31, 2011. Of these subjects, 3280 carried the diagnosis of PTSD prior to ICD implantation. Primary outcome was all-cause mortality between date of ICD implantation and end of follow-up (September 30, 2013). We used Cox proportional hazard models to compute multivariable adjusted hazard ratios with corresponding 95% confidence intervals for the relation between PTSD diagnosis and death following ICD placement.

RESULTS

During a mean follow-up of 4.21 ± 2.62 years, 11 015 deaths were reported. The crude incidence rate of death was 87.8 and 103.9/1000 person-years for people with and without PTSD, respectively. We did not find an association between presence of PTSD before or after ICD implantation and incident death when adjusted for multiple risk factors (hazard ratio: 1.003, 95% confidence interval: 0.948-1.061). In secondary analysis, no statistically significant association was found.

CONCLUSIONS

In this retrospective cohort study among more than 25 000 veterans undergoing ICD implantation, almost 13% had a diagnosis of PTSD. Subjects with PTSD were significantly younger, yet they had a higher incidence of coronary heart disease, major cardiac comorbidities, cancer, and mental health conditions. We found no association between presence of PTSD before or after ICD implantation and incident death when adjusting for all covariates.

Nocturnal phantom shock cessation with zolpidem

A 77 year old man with a biventricular ICD-pacemaker complained of painful, electric jolts disturbing him nightly from sleep. Extensive work-up including device interrogation revealed no defibrillations or arrhythmia, and he was subsequently diagnosed with phantom shocks (PS). His nightly PS symptoms terminated after starting zolpidem 10 mg each night. To date, literature review reveals fifteen articles reporting 163 phantom shock (PS) cases. PS affects 5-9% of ICD recipients. Risk factors include psychiatric disease, atrial fibrillation, NYHA functional status III or greater, prior shock storm, and intraoperative awareness during ICD placement, with defibrillation threshold testing. This report describes a successful PS intervention, and reviews the current knowledge available in the pathophysiology and treatment of PS.

Inappropriate Implantable Cardioverter-Defibrillator Shock from QRS Double Counting in the Setting of Hyperkalemia

This case shows the complexity of arrhythmia management in patients with implantable cardioverter-defibrillators (ICDs) who present with hyperkalemia. In order to prevent inappropriate ICD shock, consideration should be given to the suspension of ICD therapies while intensive care treatment of extreme electrolyte derangements is being pursued. Patients in these setting should be closely monitored until their electrocardiograms have normalized, after which the device can safely be reactivated.

Do implantable cardioverter defibrillators contribute to new depression or anxiety symptoms? A retrospective study

OBJECTIVE

In this retrospective cross-sectional study, we evaluated the existence of psychiatric symptoms which appeared after implantation of an implantable cardioverter defibrillator (ICD).

METHODS

Patients with ICDs were diagnosed using the Mini International Neuropsychiatric Interview (MINI) and were excluded if they had any psychiatric diagnosis prior to ICD implantation. Depression and anxiety were evaluated using the HAM-D and HAM-A rating scales and their attitude towards the ICD using a visual analog scale (VAS). Ninety five ICD patients with mean age of 66 years (±11.5) were recruited, 80 (84%) were men.

RESULTS

Four (4%) patients were diagnosed with new-onset MDD and one patient (1%) with anxiety. Twenty seven (28%) were found to have significant depressive symptoms (HAM-D >8), without MDD diagnosis; half of them attributing these symptoms to the device. Seven (8%) patients experienced phantom shocks and had relatively higher depressive scores (HAM-D 10.3 vs. 5.8; F = 3.696; p = 0.058). The MDD rates in our study were rather consistent with those reported for cardiac patients.

CONCLUSIONS

We suggest that ICD contributed little, if any, additional depressive or anxiety symptoms after implantation. We found that the overall attitude towards the device was positive and that shocks and phantom shocks were related to depressive symptoms.

Pilot study of the effect of lipophilic vs. hydrophilic beta-adrenergic blockers being taken at time of intracardiac defibrillator discharge on subsequent PTSD symptoms

A pathophysiological model of posttraumatic stress disorder (PTSD) posits that an overly strong stress response at the time of the traumatic event leads to overconsolidation of the event's memory in part through a central β-adrenergic mechanism. We hypothesized that the presence of a β-blocker in the patient's brain at the time of the traumatic event would reduce the PTSD outcome by blocking this effect. The unpredictable, uncontrollable discharge of an implantable intracardiac defibrillator (ICD) is experienced by most patients as highly stressful, and it has previously been shown to be capable of causing PTSD symptoms. The present pilot study evaluated a convenience sample of 18 male cardiac patients who had been taking either a lipophilic β-blocker (which penetrates the blood-brain barrier) or a hydrophilic β-blocker (which does not) at the time of a discharge of their ICD. The self- report PTSD Checklist-Specific Version quantified 17 PTSD symptoms pertaining to the ICD discharge during the month preceding the evaluation. There was a statistical trend for patients who had been taking a lipophilic β-blocker at the time of the ICD discharge to have (35%) less severe PTSD symptoms than patients who had been taking a hydrophilic β-blocker (one-tailed p=0.07, g=0.64). Further, prospective, randomized, controlled studies are suggested.

Incidence and predictors of phantom shocks in implantable cardioverter defibrillator recipients

BACKGROUND

Implantable cardioverter defibrillators (ICDs) are designed to deliver shocks or antitachycardia pacing (ATP) in the event of ventricular arrhythmias. During follow-up, some ICD recipients experience the sensation of ICD discharge in the absence of an actual discharge (phantom shock). The aim of this study was to evaluate the incidence and predictors of phantom shocks in ICD recipients.

METHODS

Medical records of 629 consecutive patients with ischaemic or dilated cardiomyopathy and prior ICD implantation were studied.

RESULTS

With a median follow-up of 35 months, phantom shocks were reported by 5.1 % of ICD recipients (5.7 % in the primary prevention group and 3.7 % for the secondary prevention group; p=NS). In the combined group of primary and secondary prevention, there were no significant predictors of the occurrence of phantom shocks. However, in the primary prevention group, phantom shocks were related to a history of atrial fibrillation (p=0.03) and NYHA class <III (p=0.05). In the secondary prevention group, there were no significant predictors for phantom shocks.

CONCLUSION

Phantom shocks occur in approximately 5 % of all ICD recipients. In primary prevention patients, a relation with a history of atrial fibrillation and NYHA class <III were significant predictors for the occurrence of phantom shocks. In the secondary prevention patients, no significant predictors were found.

Risk stratification for prevention of sudden cardiac death

OPINION STATEMENT

Sudden cardiac death (SCD) is a very prevalent cause of death in the United States. The majority of individuals who experience SCD do not survive the episode. Although there are ongoing efforts to improve resuscitation (ie, training in cardiopulmonary resuscitation, easy access to automatic external defibrillators), the primary modality addressing this public health problem is prevention by identification and treatment of high-risk cohorts. Current screening techniques have focused on identifying patients for primary prevention of ventricular tachyarrhythmias. Primary prevention therapies include medications, such as beta-blockers, statins, and angiotensin-converting enzyme inhibitors, and the implantable cardioverter defibrillator (ICD), whose use is currently focused on only the highest-risk subpopulations. The high-risk groups that are currently screened for consideration of an ICD for either primary or secondary prevention of SCD include those with a variety of cardiomyopathies, those with a history of previous aborted SCD, and those with genetic predispositions. In patients with ischemic cardiomyopathy and nonischemic dilated cardiomyopathy, the primary screening parameter to identify the highest-risk group (which is then subsequently screened for consideration of an ICD) is left ventricular ejection fraction (LVEF). Various other clinical factors and noninvasive test results are often combined with this information, but the optimal way in which this should be done has not been established. The array of noninvasive tests available includes those focusing on depolarization abnormalities, repolarization abnormalities, disturbed autonomic responses, and imaging. Unfortunately, current risk-stratification paradigms do not identify the majority of patients who will experience SCD. The fundamental reason for this is that the risk of SCD is truly lower in those without high-risk features such as depressed LVEF; however, the much larger number of patients with these lower-risk features translates into a larger absolute number of SCDs in this lower-risk group. In order to widen the scope of risk stratification, careful clinical study will be needed to develop appropriate testing strategies that can reliably identify patients at significant risk for ventricular tachyarrhythmias in the broader population.

Phantom shocks unmasked: clinical data and proposed mechanism of memory reactivation of past traumatic shocks in patients with implantable cardioverter defibrillators

BACKGROUND

Implantable cardioverter defibrillators (ICD), despite an unequivocal clinical benefit, are known to have a complex psychosocial impact on the patients. ICD shocks and the resultant psychobiological changes are known to contribute to increased levels of anxiety, depression, and post-shock stress symptoms in these patients. Phantom shock is a patient-reported perception of an ICD shock in the absence of any actual shock; however, its pathophysiological understanding is poor.

METHODS

A retrospective chart review of the University hospital ICD patients' database from June 2006 to April 2010 was conducted. A total of 38 patients with documented phantom shocks as cases and 76 age- and sex-matched patients with no phantom shocks as controls were selected from the database. Patient characteristics were analyzed for their potential association with the occurrence of phantom shocks.

RESULTS

Phantom shock patients had higher prevalence of documented depression (31.6%), anxiety (23.7%), and cocaine use (42.1%). Additionally, patients who had previous ICD shock storms were more likely to have phantom shocks (39.5%; p = 0.001). More importantly, no phantom shocks were reported in patients who did not receive defibrillation threshold testing or past ICD shock storms.

CONCLUSIONS

Phantom shocks are primarily observed in ICD patients who had prior exposure to traumatic device shocks and are more common in patients with a history of depression, anxiety, or substance abuse. A pathophysiological mechanism is proposed as a guide to potential prevention.

Chronic posttraumatic stress and its predictors in patients living with an implantable cardioverter defibrillator

INTRODUCTION

Patients with an implantable cardioverter defibrillator (ICD) show clinically relevant depression and anxiety, but little is known about their levels of posttraumatic stress. We assessed chronic posttraumatic stress attributable to a traumatic cardiac event and its predictors in patients at two time points after ICD placement.

METHODS

We investigated 107 consecutively enrolled patients (57 ± 14 years, 62% men) on average 24 ± 21 months after ICD placement (baseline) and again 41 ± 18 months later (follow-up). All patients completed the Impact of Event Scale-Revised (IES-R) to self-rate the severity of posttraumatic stress (range 0-110). The 30% of patients with the highest IES-R scores (≥ 25) at baseline were defined as PTSD cases; the same threshold was applied to define PTSD caseness at follow-up.

RESULTS

Posttraumatic stress increased from baseline to follow-up (19 ± 22 vs. 25 ± 19, p < 0.001); 19% of patients had PTSD at both assessments, 12% at baseline only, and 18% at follow-up only. Female gender as well as greater peritraumatic dissociation and depression predicted greater posttraumatic stress at baseline (p-values ≤ 0.041). Greater baseline posttraumatic stress, helplessness, alexithymia, and ≥ 5 shocks during follow-up all predicted greater posttraumatic stress at follow-up (p-values ≤ 0.029). Female gender, helplessness, and depression predicted PTSD at baseline (p-values ≤ 0.022); low education and posttraumatic stress at baseline predicted PTSD at follow-up (p-values ≤ 0.003).

CONCLUSIONS

Between 2 and 5.5 years post-ICD placement chronic posttraumatic stress slightly increased and nearly one-fifth of patients had newly developed PTSD. The identified psychological predictors of long-term chronicity of posttraumatic stress might particularly inform behavioral interventions for ICD recipients.

Gender disparities in psychological distress and quality of life among patients with an implantable cardioverter defibrillator

A subset of patients with an implantable cardioverter defibrillator (ICD) reports psychological distress and poor quality of life (QoL). Gender is one of the factors that has been proposed to explain individual differences in these outcomes. In this viewpoint, we (1) review the evidence for gender disparities in psychological distress and QoL in ICD patients by means of a systematic review, and (2) provide recommendations for future research and clinical implications. A systematic search of the literature identified 18 studies with a sample size ≥ 100 that examined gender disparities in anxiety/depression and QoL in ICD patients (mean prevalence of women = 21%; mean age = 62 years). Our review shows that there is insufficient evidence to conclude that gender per se is a major autonomous predictor for disparities in psychological distress and QoL in ICD patients. Women had a higher prevalence of anxiety and poorer QoL in some studies, but there was no statistically significant gender effect in relation to 80% (26/32) of the outcomes reported in the 18 studies. Studies are warranted that are designed a priori and sufficiently powered to examine gender disparities in distress and QoL outcomes in order to establish the exact gender-specific effect. Due to a need to explore the complexity of this issue further, at this time, caution is warranted with respect to the clinical implications.

The impact of anxiety on conversion from mild cognitive impairment to Alzheimer's disease

OBJECTIVE

To compare state and trait anxiety in mild cognitive impairment (MCI) patients and matched control subjects, and to assess the impact of these variables in predicting conversion to Alzheimer's disease.

METHODS

One hundred and forty-eight patients with MCI, broadly defined, were assessed and followed systematically. Baseline predictors for follow-up conversion to AD (entire sample: 39/148 converted to Alzheimer's disease (AD)) included the Spielberger State-Trait Anxiety Inventory (STAI).

RESULTS

At baseline evaluation, MCI patients had higher levels of state and trait anxiety than controls, with no differences between future AD converters (n = 39) and non-converters. In age-stratified Cox proportional hazards model analyses, STAI State was not a significant predictor of conversion to AD (STAI State < or =30 vs. > 30 risk ratio, 1.68; 95% CI, 0.75, 3.77; p = 0.21), but higher Trait scores indicated a lower risk of conversion when STAI State, education, the Folstein Mini-Mental State Examination and HAM-D (depression score) were also included in the model (STAI Trait < or =30 vs. > 30 risk ratio, 0.36; 95% CI, 0.16, 0.82; p = 0.015).

CONCLUSIONS

In contrast to two other recent studies that showed anxiety predicted cognitive decline or conversion to AD, in this clinic-based sample, state anxiety was not a significant predictor. However, higher Trait anxiety predicted a lower risk of future conversion to AD. Further research with systematic long-term follow-up in larger samples is needed to clarify the role of state and trait anxiety in predicting MCI conversion to AD.

Patient expectations from implantable defibrillators to prevent death in heart failure

BACKGROUND

Indications for implantable cardioverter-defibrillators (ICDs) in heart failure (HF) are expanding and may include more than 1 million patients. This study examined patient expectations from ICDs for primary prevention of sudden death in HF.

METHODS AND RESULTS

Study participants (n = 105) had an EF <35% and symptomatic HF, without history of ventricular tachycardia/fibrillation or syncope. Subjects completed a written survey about perceived ICD benefits, survival expectations, and circumstances under which they might deactivate defibrillation. Mean age was 58, LVEF 21%, 40% were New York Heart Association Class III-IV, and 65% already had a primary prevention ICD. Most patients anticipated more than10 years survival despite symptomatic HF. Nearly 54% expected an ICD to save >or=50 lives per 100 during 5 years. ICD recipients expressed more confidence that the device would save their own lives compared with those without an ICD (P < .001). Despite understanding the ease of deactivation, 70% of ICD recipients indicated they would keep the ICD on even if dying of cancer, 55% even if having daily shocks, and none would inactivate defibrillation even if suffering constant dyspnea at rest.

CONCLUSIONS

HF patients anticipate long survival, overestimate survival benefits conferred by ICDs, and express reluctance to deactivate their devices even for end-stage disease.

Psychological intolerance to implantable cardioverter defibrillator

BACKGROUND

Implantable cardioverter defibrillators (ICD) are mobile implantable cardiac devices for immediate treatment of live threatening ventricular arrhythmias. However, these devices can affect patients, physiologically, psychologically and have effects on electrical devices.

CASE REPORT

The case of a 61-year-old patient is reported. The patient came for regular 3-months visits with his ICD and complained about electromagnetic interference with all household electrical appliances, especially refrigerator and digital television set-top box. He described several phantom shocks when he came close to the electrical appliances. He noted the exact times and symptoms of the episodes but the device memory did not record anything.

CONCLUSION

This case demonstrates the rare occurrence of psychological intolerance to implanted ICD shortly after implant. The device was programmed for higher sensitivity. The patient was calmed and reassured about the reprogramming.

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.

An updated review of implantable cardioverter/defibrillators, induced anxiety, and quality of life

During the past 2 years the number of studies examining psychopathology and quality of life after ICD implantation has increased dramatically. Variables assessed have included recipient age, gender, and social support network. How recipients respond to having the device, particularly after experiencing firing, has been evaluated in light of new depression and anxiety disorder diagnoses as well as premorbid personality structure. Now the picture of what is known is, if anything, cloudier than it was 2 years ago, with little definitive and much contradictory data emerging in most of these categories. It still seems clear that in a significant minority of ICD recipients the device negatively affects quality of life, probably more so if it fires. Education about life with the device before receiving it remains paramount. Reports continue to appear of patients developing new-onset diagnosable anxiety disorders such as panic and posttraumatic stress disorder. Until recently the strongest predictors of induced psychopathology were considered to be the frequency and recency of device firing. It now seems that preimplantation psychologic variables such as degree of optimism or pessimism and an anxious personality style may confer an even greater risk than previously thought. Certainly many variables factor into the induction of psychopathology in these patients. Among these factors are age, gender, and perception of control of shocks, as well as the predictability of shocks and psychologic attributions made by the patient regarding the device. Another source of variability is this population's medical heterogeneity. Some patients receive ICDs after near-death experiences; others get them as anticipatory prophylaxis. Some have longstanding and entrenched heart disease; others were apparently healthy before sudden dangerous arrhythmias. Diagnoses as diverse as myocardial infarction in the context of advanced coronary artery disease and dilated cardiomyopathy after acute viral infection may warrant ICD placement. Moreover the course of cardiac disease after ICD placement may vary from relative stability to continuing disease progression and severe functional compromise. Unless these and other pre- and postimplantation differences are taken into account, it is almost impossible to make meaningful comparisons between studies. Ideally, future research would consist either of large-scale, randomized, prospective studies using validated structured-interview tools to supplement a literature dominated by self-report measures, unstructured assessments, and anecdotal reports, or of smaller studies designed to focus on particular diagnostic subsets. As ICDs become the standard of care for potentially life-threatening arrhythmias, the rate of implantations continues to increase. Because negative emotions have been linked to an increased incidence of arrhythmias, and untreated or unrecognized psychiatric illness can interfere with adaptation to an ICD, assessing and managing both pre-existing and induced psychiatric disorders becomes even more critical. Greater research attention should be paid to determining which patients meet criteria for anxiety disorders before and after implantation and what premorbid traits predispose to postimplantation psychopathology. The authors predict that psychiatrists will be involved increasingly in caring for this population, offering insights into treatment options that increase the likelihood of successful ICD acceptance and decrease the psychosocial costs of these devices.