Incidence and predictors of phantom shocks in implantable cardioverter defibrillator recipients

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.

Effects of renal denervation therapy on cardiac function and malignant arrhythmia in patients with reduced left ventricular ejection fraction and narrow QRS complexes treated with implantable cardioverter defibrillator

Objective: The purpose of this study was to explore the effects of renal denervation (RDN) on cardiac function and malignant arrhythmia in patients with reduced left ventricular ejection fraction (HFrEF) and narrow QRS treated with an implantable cardioverter defibrillator (ICD).

Methods: A total of 20 eligible HFrEF patients [left ventricular ejection fraction (LVEF) <40%] and narrow QRS complexes (QRS duration <120 ms) were randomized into either the ICD plus RDN group or the ICD only group during 17 April 2014 to 22 November 2016. Clinical data, including clinical characteristics, blood biochemistry, B-type natriuretic peptide, echocardiographic indexes, 6-min walk distance (6MWD), New York Heart Association (NYHA) classification, and count of ICD discharge events before and after the operation were analyzed. Patients were followed up for up to 3 years post ICD or ICD plus RDN.

Results: Baseline clinical data were comparable between the two groups. Higher LVEF (%) (mixed model repeated measure, p = 0.0306) (39.50% ± 9.63% vs. 31.20% ± 4.52% at 1 year; 41.57% ± 9.62% vs. 31.40% ± 8.14% at 3 years), systolic blood pressure (p = 0.0356), and longer 6MWD (p < 0.0001) as well as reduction of NYHA classification (p < 0.0001) were evidenced in the ICD plus RDN group compared to ICD only group during follow-up. Patients in the ICD plus RDN group experienced fewer ICD discharge events (2 vs. 40) and decreased diuretic use; rehospitalization rate (30% vs. 100%, p = 0.0031) and cardiogenic mortality rate (0% vs. 50%, p = 0.0325) were also significantly lower in the ICD plus RDN group than in the ICD only group during follow-up.

Conclusion: ICD implantation plus RDN could significantly improve cardiac function and cardiac outcome as well as increase exercise capacity compared to ICD only for HFrEF patients with narrow QRS complexes.

Phantom Shocks Associated With a Wearable Cardioverter Defibrillator

Wearable cardioverter defibrillators (WCDs) are external devices capable of continuous cardiac rhythm monitoring as well as automatic detection and defibrillation of potentially life-threatening arrhythmias such as ventricular tachycardia (VT) and ventricular fibrillation (VF). They are an alternative approach for patients when an implantable cardioverter defibrillator (ICD) is not appropriate. Although treatment with ICD is considered highly effective for the primary and secondary prevention of sudden cardiac death (SCD) in high-risk patients susceptible to VT and VF, patients may still experience psychological difficulties such as fear of shock, avoidance of normal behaviors and reduced quality of life. One of these phenomena is phantom shock (PS), which is defined as a perception of having received a shock with no evidence of recorded defibrillation upon device interrogation. While PS has been reported in the ICD literature, to the best of our knowledge, we present the first known case of WCD-related PS. We also present a review of the current literature to explore the prevalence of PS, the factors associated with its pathogenesis and interventional studies aimed at reducing its occurrence. We highlight this case because PS is considered a phenomenon that few recognize, which should be discriminated from real device shocks before clinicians initiate treatment, device reprogramming or device discontinuation. We describe the psychosocial factors associated with PS to emphasize the importance of managing any associated psychiatric disorders and psychosocial factors both before and after initiation of device treatment.

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.

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.

Perceptions and experiences of patients living with implantable cardioverter defibrillators: a systematic review and meta-synthesis

Background

Sudden cardiac deaths have become a growing major public health concern that affects the world. Despite the various etiologies, life-threatening cardiac arrhythmias attribute the main cause of sudden cardiac deaths. Therefore in certain groups of high-risk patients, the Implantable Cardioverter Defibrillator (ICD) has been recommended as either a secondary or primary prophylactic method of prevention.

Objective

To summarise the perceptions of ICD recipients and provide an overview of their experiences with regards to the quality of life, coping strategies, and learning needs.

Methods

A systematic search was conducted using CINAHL, MEDLINE, PsycINFO, Scopus, Cochrane Library, and Web of Science. Primary research articles published from January 2005 to January 2016 that met the inclusion criteria were selected and assessed for methodological quality.

Results

Thirty-nine articles consisting of 16 qualitative studies, 22 quantitative studies, and 1 mixed methods study were included for the meta-synthesis. Findings extracted from these studies were grouped into eight subthemes with ‘living the ICD experience: a constant process of redefining oneself’ emerging as an over-arching theme.

Conclusion

This review provides insight into the perspectives and experiences of ICD recipients. Current evidence highlights the need for healthcare professionals to improve future care standards and develop a patient-centric holistic program that meets the specific needs of ICD recipients. Moreover, future studies are required to address the research gaps identified and also explore the perceptions of patients living with ICD in the Asian context.

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.

Antitachycardia pacing for reduction of implantable cardioverter-defibrillator shocks

Antitachycardia pacing (ATP) strategies represent safe, effective, and painless therapy for ventricular tachyarrhythmias, with a large body of clinical evidence supporting their routine use in both primary and secondary implantable cardioverter-defibrillator recipients. This article details the evidence supporting the use of standardized and validated ATP strategies for primary prevention patients and the conceptual framework to design effective ATP strategy for secondary prevention patients.

Follow-up of implantable cardioverter-defibrillator therapy: comparison of coronary artery disease and dilated cardiomyopathy

PURPOSE

Since several large trials have proven the effectiveness of implantable cardioverter-defibrillators (ICDs) in patients with left ventricular dysfunction, disadvantages have become more apparent. As the prognosis of patients with cardiovascular diseases is improving, assessment of ICD patients and re-evaluation of the current guidelines is mandatory. We aimed to evaluate differences in mortality and occurrence of (in)appropriate shocks in ICD patients with coronary artery disease (CAD) or dilated cardiomyopathy (DCM).

METHODS

In a large teaching hospital, all consecutive patients with systolic dysfunction due to CAD or DCM who received an ICD with and without resynchronisation therapy, were collected in a database.

RESULTS

A total of 320 consecutive patients (age 67 ± 10 years) were classified as CAD patients and 178 (63 ± 11 years) as DCM patients. Median follow-up was 40 months (interquartile range [IQR] 23─57 months). All-cause mortality was 14 % (CAD 15 % vs DCM 13 %). Appropriate shocks occurred in 13 % of all patients (CAD 15 % vs DCM 11 %, p = 0.12) and inappropriate shocks occurred in 10 % (CAD 8 % vs DCM 12 %, p = 0.27). Multivariate analysis demonstrated impaired left ventricular ejection fraction, QRS >120, age ≥75 years and low estimated glomerular filtration rate as predictors for all-cause mortality. Predictors for inappropriate shocks were permanent and paroxysmal atrial fibrillation.

CONCLUSION

Mortality rates were similar in patients with CAD and DCM who received an ICD. Furthermore, no differences were found in the occurrence of appropriate and inappropriate ICD interventions between these patient groups.

State of the art of ICD programming: Lessons learned and future directions

The lifesaving benefits of implantable cardioverter defibrillator (ICD) therapy are more and more weighted against possible harm (e.g. unnecessary device therapy, procedural complications, device malfunction etc.) which might have adverse effects on patients' perceived health status and quality of life. Hence, there has been an increasing interest in the optimisation of ICD programming to prevent inappropriate and appropriate but unnecessary device therapy. The purpose of the current report is to give an overview of research into the optimisation of ICD programming and present the design of the on-going ENHANCED-ICD study. The ENHANCED-ICD study is a prospective, safety monitoring study enrolling 60 primary and secondary prophylactic ICD patients at the University Medical Center Utrecht. Patients implanted with any type of ICD with SmartShock technology(TM), and between 18-80 years of age, were eligible to participate. In all patients a prolonged detection of 60/80 intervals was programmed. The primary objective of the study is to investigate whether enhanced programming to further reduce ICD therapies is safe. The secondary objective is to examine the impact of enhanced programming on (i) antitachycardia pacing and shocks (both appropriate and inappropriate) and (ii) quality of life and distress. The first results of the ENHANCED-ICD study are expected in 2015.

Pre-hospital discharge testing of defibrillator without anesthesia: effects on psychological symptoms during clinical follow-up

OBJECTIVE

After the implantation of an implantable cardioverter-defibrillator (ICD), patients often fear therapeutic shock. The extent to which the experience of pre-hospital discharge (PHD) testing without anesthesia after ICD implantation, under observation by a physician, affects shock-related anxiety symptoms on follow-up has not been investigated as yet.

METHODS

In a prospective, randomized controlled trial, 44 patients with a primary prevention indication for an ICD were randomly assigned to experience PHD testing without anesthesia (n = 23) or with anesthesia (n = 21). Patients were longitudinally evaluated before (T(1)), shortly after (T(2)), and 3 months after (T(3)) PHD testing. During the respective PHD testings, the course of patients' serum cortisol release was measured.

RESULTS

During PHD testing, patients without anesthesia showed a significantly higher serum cortisol release than patients with anesthesia (F(4,152) = 22.227, p < .001). Patients who experienced PHD testing without anesthesia felt significantly safer with the ICD (U = 165.000, p = .040), would significantly more often recommend other patients to undergo PHD testing without anesthesia (χ(2) = 12.013, p = .002), and showed significantly lower levels of general shock-related anxiety shortly afterward (F(1,42) = 6.327, p = .02) and 3 months after PHD testing (F(1,41) = 8.603, p = .005).

CONCLUSIONS

The implementation of PHD testing without anesthesia is associated with lower anxiety concerning therapeutic shock. Patients should be advised about the effects of PHD testing without anesthesia on their psychological well-being in the long run.