Defibrillator Patients Research Articles

P1026The correlation between the PRAETORIAN Score in Subcutaneous Implantable Defibrillator Patients and the Defibrillation Threshold

P1026The correlation between the PRAETORIAN Score in Subcutaneous Implantable Defibrillator Patients and the Defibrillation Threshold

CorVue algorithm efficacy to predict heart failure in real life: Unnecessary and potentially misleading information?

Heart failure (HF) hospitalizations have a negative impact on quality of life and imply important costs. Intrathoracic impedance (ITI) variations detected by cardiac devices have been hypothesized to predict HF hospitalizations. Although Optivol™ algorithm (Medtronic, Minneapolis, MN, USA) has been widely studied, CorVue™ algorithm's (St. Jude Medical, St. Paul, MN, USA) long-term efficacy has not been systematically evaluated in a "real-life" cohort. CorVue™ was activated in implantable cardioverter defibrillator (ICD)/cardiac resynchronization therapy defibrillator (CRT-D) patients to store information about ITI measures. Clinical events (new episodes of HF requiring treatment and hospitalizations) and CorVue™ data were recorded every 3 months. Appropriate CorVue™ detection for HF was considered if it occurred in the 4 prior weeks to the clinical event. Fifty-three ICD/CRT-D (26 ICD and 27 CRT-D) patients (67 ± 1 years old, 79% male) were included. Device position was subcutaneous in 28 patients. At inclusion, mean left ventricular ejection fraction was 25 ± 7% and 27 patients (51%) were in New York Heart Association class I, 18 (34%) in class II, and eight (15%) in class III. After a mean follow-up of 17 ± 9 months, 105 ITI drops alarms were detected in 32 patients (60%). Only six alarms were appropriate (true positive) and required hospitalization. Eighteen patients (34%) presented 25 clinical episodes (12 hospitalizations and 13 emergency room/ambulatory treatment modifications). Nineteen of these clinical episodes (76%) remained undetected by the CorVue™ (false negative). Sensitivity of CorVue™ resulted in 24%, specificity was 70%, positive predictive value of 6%, and negative predictive value of 93%. CorVue™ showed a low sensitivity to predict HF events. Therefore, routinely activation of this algorithm could generate misleading information.

Será a implantação de desfibrilhador menos útil nos doentes com cardiopatia não isquémica?

Introduction and ObjectiveThe benefits of implanted defibrillators in patients with ischemic heart disease (IHD) are well known. However, the evidence is less robust in patients with non‐ischemic heart disease (non‐IHD). We aimed to determine whether patients with non‐IHD have a similar incidence of appropriate shocks and all‐cause mortality compared to those with IHD. MethodsIn a retrospective single‐center study we analyzed all patients with implantable cardioverter‐defibrillators or cardiac resynchronization therapy‐defibrillators implanted for primary prevention between 2004 and 2014. The population was divided into two groups: patients with IHD and patients with non‐IHD. The composite endpoint was appropriate shock and all‐cause mortality. ResultsTwo hundred and eighty‐one patients were studied, of whom 187 (66%) had IHD. Patients with IHD were older, more frequently male and with more cardiovascular risk factors. Mean follow‐up was 55±42 months. Thirty‐four patients (18%) with IHD and 20 patients (21%) with non‐IHD had an appropriate shock (p=0.64). Eighty‐nine patients (47%) with IHD and 36 (38%) with non‐IHD died during follow‐up (p=0.19). The rate of shocks or death over time was similar in patients with IHD and non‐IHD according to Kaplan‐Meier survival curve analysis (log‐rank p=0.10). ConclusionIn this population, there were no differences in appropriate shocks or all‐cause mortality in the two groups.

The incidence and impact of implantable cardioverter defibrillator shocks in the last phase of life: An integrated review.

Background:Although the implantable cardioverter defibrillator is successful in terminating life threatening arrhythmias, it might give unwanted shocks in the last phase of life if not deactivated in a timely manner.Aims:This integrated review aimed to provide an overview of studies reporting on implantable cardioverter defibrillator shock incidence and impact in the last phase of life.Methods and results:We systematically searched five electronic databases. Studies reporting on the incidence and/or impact of implantable cardioverter defibrillator shocks in the last month of life were included. Fifteen studies were included. Two American studies published in 1996 and 1998 reported on the incidence of shocks in patients who died non-suddenly: incidences were 24% and 33%, respectively, in the last 24 hours, and 7% and 14%, respectively, in the last hour of life. Six American studies and one Danish study published between 1991–1999 reported on patients dying suddenly: incidences were 41% and 68% in the last 24 hours and 22–66% in the last hour. Four American studies and two Swedish studies published between 2004–2015 did not distinguish the cause of death: incidences were 17–32% in the last month, 3–32% in the last 24 hours, and 8% and 31% in the last hour of life. Three American studies published between 2004–2011 reported that shocks in dying patients are painful and distressing for patients, and distressing for relatives and professional caregivers.Conclusion:If the implantable cardioverter defibrillator is not deactivated in a timely manner, a potentially significant proportion of implantable cardioverter defibrillator patients experience painful and distressing shocks in their last phase of life.

Exploring the patients' experiences of living with a subcutaneous implantable cardioverter defibrillator.

The implantable cardioverter defibrillator provides effective treatment for the prevention of sudden cardiac arrest but significant risks associated with transvenous implantation persist. The subcutaneous implantable cardioverter defibrillator has proven to be an alternative and innovative treatment option for select patients to mitigate these risks. Obtaining the patients' perspectives can provide clinicians with essential information to guide implant selection, procedural decision-making, and support patient management. Conventional implantable cardioverter defibrillator patients have reported shock-related anxiety, fear, insufficient education, and challenges adapting to physical and psychological changes. Little evidence exists to determine whether differences between the subcutaneous implantable cardioverter defibrillator and conventional implantable cardioverter defibrillator allow for the transferability of our current knowledge to the care and management of this population. The purpose of this study was to explore patients' experiences of living with a subcutaneous implantable cardioverter defibrillator including the decision-making process, implant, and follow-up care processes. Using an exploratory qualitative approach, semi-structured interviews were conducted by telephone with 15 participants who underwent subcutaneous implantable cardioverter defibrillator implant. Analysis revealed five main themes: (a) influences on decision-making; (b) unmet education needs; (c) physical impact; (d) psychological impact; and (e) recommendations. As a new technology, little knowledge of the subcutaneous implantable cardioverter defibrillator exists outside of the tertiary implanting sites, therefore developing new strategies to increase learning and dissemination is essential. Although similarities exist in our findings to those of conventional implantable cardioverter defibrillators, there are significant differences in the decision-making process and physical impact which require individualized care planning and development of strategies to provide a patient-centered approach to care.

P029: A descriptive analysis of defibrillation vector change for prehospital refractory ventricular fibrillation

Introduction: Patients in ventricular fibrillation (VF) who do not respond to standard Advanced Cardiac Life Support treatments are deemed to be in refractory VF (rVF). The ideal prehospital treatment for patients with rVF remains unknown. Double sequential external defibrillation (DSED) has been proposed as a viable option for patients in rVF. Although the mechanism by which DSED terminates rVF remains unknown, one theory is that the change in defibrillation vector that occurs may contribute. The objective of this study was to describe clinical outcomes for patients presenting in rVF during out-of-hospital cardiac arrest (OOHCA) for those who underwent vector change defibrillation, compared to those who received standard treatment. Methods: This was a retrospective chart review of adult (18 years) patients presenting in rVF during OOHCA over 15 months beginning in March 2016. Patients who underwent vector change defibrillation had a change in pad position (anterior-anterior to anterior-posterior) after 3 or more consecutive shocks. Termination of rVF was defined as the absence of VF after a vector change or standard shock during the next rhythm analysis. Results: There were 372 OOHCA, with 25 (6.7%) patients meeting our definition of rVF. Of these, 16 (64.0%) patients (median age 62 years, 81.3% male) had vector change after a median (IQR) of 3 (3.0-4.0) paramedic defibrillation attempts. Median (IQR) time to vector change defibrillation was 8.8 (7.1-11.1) minutes. Eight (50%) patients had termination of rVF after the first vector change shock, 6 (37.5%) had prehospital return of spontaneous circulation (ROSC) and 5 (31.3%) patients survived to hospital discharge. Of the 9 rVF patients who did not have vector change, median age was 63 years and 88.9% were male. The median (IQR) number of defibrillations within this group was 5 (4.5-7.0). No patients converted after the 4th defibrillation. Prehospital ROSC was achieved in 3 (33.3%) patients and 5 (55.5%) patients were transported while in rVF . Three patients (33.3%) survived to hospital discharge. Conclusion: This is preliminary evidence that vector change defibrillation in patients with rVF may result in VF termination. A randomized controlled trial is warranted to test whether or not vector change has a role in the termination of rVF.

Vagus Nerve Stimulation and External Defibrillation during Resuscitation; a Letter to Editor.

Dear Editor; External defibrillation in patients with implanted neuromodulatory devices is a crucial therapeutic challenge. We report a 63-year-old male patient with refractory epilepsy (RE) after recurrent ischaemic strokes in the middle cerebral artery and in the anterior cerebral artery territory 26 and 23 years ago. He received various therapeutic interventions to achieve seizure control with insufficient success. Therefore, vagus nerve stimulation (VNS) (model Pulse 102, Aspire SR, Cyberonics Inc, Houston, Texas) was applied via insertion of a pulse generator in the left upper chest in 2011. VNS stimulation settings were: output current 1.0 mA, pulse width 500 µs, frequency 30 Hz, 30s ON, 3.0 minute OFF. A reduction of seizure frequency was achieved. Last antiepileptic therapy consisted of levetiracetam 1500 mg td, valproate 1000 mg td, and eslicarbazepine 800 mg td. In 2016, he was admitted because of generalized seizure and aspiration pneumonia. During hospital stay he suffered a cardiac arrest (CA) with pulseless ventricular tachycardia (VT) caused by fulminant pulmonary artery embolism. After successful resuscitation, the patient experienced return of spontaneous circulation (ROSC). During resuscitation, biphasic electric shocks were applied using 150 Joule and subsequently 360 Joule with patches placed approximately 10 cm parasternal and at the left chest below the VNS. After successful ROSC the VNS was checked again and no malfunction could be detected. Stimulation settings were not changed. Impedance was normal. Seizures were not observed during the remaining day. Unfortunately, the patient died within one day after successful resuscitation and ROSC because of therapy refractory circulatory insufficiency. VNS is an established therapeutic approach in treatment of TRE in children and adults to achieve reduction of seizure frequency with proven safety and efficacy. The safety of VNS in emergency situations like cardiac arrest due to VF with need of external defibrillation and application of large amounts of electrical energy is not clear. External defibrillation in VNS patients may potentially be harmful. The literature concerning external defibrillation during resuscitation or external cardioversion (EC) in patients with implanted electronic devices in neurological disorders is sparse. In patients with cardiac pacemakers external defibrillation may damage the cardiac device. EC applied to deep brain stimulation (DBS) patients may cause thalamotomy or DBS failure. Application of electroconvulsive therapy in psychiatric disorders seems to be safe. Two cases of electroconvulsive therapy (ECT) in VNS have been reported by Sharma et al. The first patient was a 66-year old female with major depression and the second one, a 57-year-old male with a history of bipolar disorder. Both had VNS for therapy refractory psychiatric illness. ECT was applied because of further worsening of the mental state without malfunction of the VNS device. To our knowledge, this is the first case of external defibrillation in a patient with VNS for TRE without alteration of the neurostimulator’s function. External defibrillation applied to VNS patients seem to be safe and effective. Several steps should be taken to minimize the electrical current flowing through the neurostimulator. First, position the patches as far away as possible from the VNS at least 10 cm each. Second, position the patches perpendicular to the VNS; use the lowest clinically appropriate output setting, and, finally, confirm that the VNS is functioning properly after defibrillation.

Abstract 249: Quality of Medical Advice Provided Online Between Anonymous Members of a Message Board for Implanted Defibrillator Patients

Background: As therapeutic interventions across medicine increase in complexity, most patients use the internet to research health issues to inform decisions, including whether or not to accept certain tests, medications, or devices. Online information is available any time and can be reviewed indefinitely by patients, filling some educational needs outside of appointments with care providers. The quality of information patients encounter online varies, and we found no models for examining anonymously-created medical advice in extant literature. We used implanted defibrillator (ICD) treatment, characterized by patient educational and supportive needs across the trajectory of care, as a model. We sought to characterize the quality of medical information provided between commenters on a typical patient-facing internet message board discussing ICDs. Methods: Two years’ of discussions appearing on a dedicated message board for ICD patients were qualitatively analyzed using a mixed-deductive framework. Discussions were first analyzed for instances in which members provided medical advice. This advice was then characterized for 1) topical area and 2) quality. Results: We identified 82 instances of medical advice within 127 discussions. Advice covered six topical areas: 1) Device Information, 2) Programming, 3) Cardiovascular Disease, 4) Lead Management, 5) Activity Restriction, and 6) Management of Other Conditions. Across all advice, 50.0% was deemed Generally Appropriate, 24.4% Inappropriate for Most Patients, 6.1% Controversial, and 19.5% Without Sufficient Context. Proportions of quality categories varied between topical areas. Representative examples of advice provided between members will be included. Conclusions: Patients use online medical information to understand conditions and treatment options. A number of efforts have been made to understand the quality of professionally-created educational content, while ours describes the quality of advice being provided between anonymous members of an online message board. The quality of advice varied considerably, both by topical area and the specificity of advice. This analysis provides a methodologic model by which to describe the quality of patient-generated material available online.

Incidence and Clinical Significance of New-Onset Device-Detected Atrial Tachyarrhythmia: A Meta-Analysis.

Despite the clear association between atrial fibrillation and risk for thromboembolic events (TEs), the clinical significance of new-onset device-detected atrial tachyarrhythmia (DDAT) and TE remains disputed. We aimed to determine the risk of TE in patients with new-onset DDAT. The OVID Medline, Cochrane, and Scopus databases (inception to November 2016) were searched. Randomized controlled trials, prospective, or retrospective studies of pacemaker or defibrillator patients reporting incidence of DDAT were selected. Summary statistics were used for analysis. Of 4893 reports identified, 28 studies following 24 984 patients were included: average age 69.9 years, 34.7% women, mean study duration 21.8±18.6 months. New-onset DDAT was observed in 23% of patients. Among 9 studies (n=8181) reporting TE, the absolute incidence was 2.1%. TE risk was significantly greater among patients with new-onset DDAT (relative risk [RR], 2.88; 95% CI, 1.79-4.64; P<0.001). TE risk was correlated with DDAT duration, with an increased risk associated with DDAT ≥5 minutes (RR, 3.86; 95% CI, 2.04-7.30; P<0.001) compared with <1 minute (RR, 1.77; 95% CI, 1.15-2.74; P=0.01). Notably, the risk of TE was also increased in patients with adjudicated atrial electrograms (RR, 3.60; 95% CI, 2.06-6.30; P<0.001) compared with nonadjudicated electrograms (RR, 2.05; 95% CI, 1.06-3.97; P=0.03), even when lower mean thresholds for detection were used. New-onset DDAT is common, affecting close to one quarter of all patients with implanted pacemakers or defibrillators. Adjudication of atrial electrograms further identifies at-risk patients, even when relatively short detection thresholds are used.

Implantable Defibrillators in Patients with Chronic Kidney Disease: Think Twice

Implantable cardioverter-defibrillators (ICDs) can prolong survival in various patient populations, as shown in secondary prevention trials and primary

Clinical outcomes after upgrading from pacemakers to cardiac resynchronization therapy.

Right ventricular pacing may lead to heart failure (HF). Upgrades from pacemakers to cardiac resynchronization therapy (CRT) were excluded from most randomized, controlled trials. We sought to determine the long-term outcomes of upgrading from pacemakers to CRT with (CRT-D) or without (CRT-P) defibrillation in patients with no history of sustained ventricular arrhythmias. In this observational study, clinical events were quantified in relation to the type of implant (de novo or upgrade) and device type at upgrade (CRT-P or CRT-D). Patients underwent CRT implantation (n=1,545; 1,314 [85%] de novo implants and 231 [15%] upgrades) over a median of 4.6 years [interquartile range: 2.4-7.0]. In analyses of crude event rates, upgrades had a higher total mortality (adjusted hazard ratio [aHR]: 1.33; 95% confidence interval [CI] 0.10-1.61), a higher total mortality or HF hospitalization (aHR: 1.26; 95% CI 1.05-1.51), but similar mortality or hospitalization for major adverse cardiac events (MACEs, aHR: 1.15; 95% CI 0.96-1.38). No group differences emerged in any of these endpoints after propensity score matching. After inverse probability weighting in upgrades, total mortality (HR: 0.55; 95% CI 0.36-0.73), total mortality or HF hospitalization (HR: 0.56; 95% CI 0.34-0.79), and total mortality or hospitalization for MACEs (HR: 0.61; 95% CI 0.40-0.82) were lower after CRT-D than after CRT-P. Upgrading from pacemakers to CRT was associated with a similar long-term risk of mortality and morbidity to de novo CRT. After upgrade, CRT-D was associated with a lower mortality than CRT-P.

Wearable Cardioverter Defibrillators in Patients with Recent Cardiac Surgery

Wearable Cardioverter Defibrillators in Patients with Recent Cardiac Surgery

Magnetic resonance imaging-conditional devices: Where have we reached today?

Scientific growth in the field of magnetic resonance imaging (MRI) and cardiac devices has been exponential in recent decades. Cardiac implantable electronic devices due to their ferromagnetic constituents in leads and device body have always been an issue if patients need MRI. MRI is relatively safe. Recent introduction of changes in leads and device body constituents renders them less ferromagnetic, making MRI less frightening to a certain extent. Simultaneously, there is increasing research interest in MRI. Not only anatomy and pathology but also physiology of cardiac and nervous structures can be imaged. It is estimated that 53%–64% of intracardiac defibrillator (ICD) patients will require an MRI determination over a 10-year time horizon, highlighting the importance of MRI-conditional devices for this patient population. In this article, we briefly describe evolution and current status of conditioning of cardiac devices to make them MRI-friendly and briefly discuss where we are in terms of our physician role with respect to MRI-conditional devices.

Psychological distress and health-related quality of life in implantable cardioverter defibrillator patients with coronary artery disease

Psychological distress and health-related quality of life in implantable cardioverter defibrillator patients with coronary artery disease

Sleep disturbance in patients with an implantable cardioverter defibrillator: Prevalence, predictors and impact on health status.

Background:Sleep disturbances are highly prevalent in patients with cardiac diseases and associated with poor health outcomes. However, little is known about sleep disturbance in patients with an implantable cardioverter defibrillator.Aims:We examined the prevalence and predictors of sleep disturbance and the impact on perceived health status in a Dutch cohort of implantable cardioverter defibrillator patients.Methods:Patients (n=195) enrolled in the Web-based distress program for implantable cardioverter defibrillator patients (WEBCARE) trial completed questionnaires at the time of implantable cardioverter defibrillator implantation, three, six and 12 months afterwards. Sleep disturbance was assessed with the corresponding item #3 of the Patient Health Questionnaire 9.Results:At baseline, 67% (n=130) reported sleep disturbance (cut off ≥1). One year later, the prevalence was 57% (n=112). Younger age (odds ratio=0.96, 95% confidence interval 0.92–0.99; p=0.012) and high negative affectivity/low social inhibition (odds ratio=4.47, 95% confidence interval 1.52–13.17; p=0.007) were associated with sleep disturbance at 12 months in adjusted analyses. Sleep disturbance was not associated with health status at 12 months. Charlson Comorbidity Index, anxiety, Type D personality and high negative affectivity/low social inhibition were associated with impaired health status at follow-up.Conclusions:Sleep disturbance was highly prevalent in patients with an implantable cardioverter defibrillator. Younger age and high negative affectivity predicted sleep disturbance 12 months post-implantation independent of other demographic, clinical, intervention and psychological covariates. Sleep disturbance was not associated with impaired health status at the 12-month follow-up.

Appropriate implantable cardioverter-defibrillator interventions in cardiac resynchronization therapy-defibrillator (CRT-D) patients undergoing device replacement: time to downgrade from CRT-D to CRT-pacemaker? Insights from real-world clinical practice in the DECODE CRT-D analysis.

Ventricular tachycardia (VT)/ventricular fibrillation (VF) occurrence after cardiac resynchronization therapy-defibrillator (CRT-D) replacement is unknown; hence, there is no practical guideline to recommend either CRT-D or CRT-pacemaker at the time of device replacement. We observed the 1-year VT/VF occurrence after CRT-D replacement in a subanalysis of the Detect Long-term Complications after ICD Replacement (DECODE) registry. A total of 332 consecutive patients who had undergone CRT-D replacement from 2013 to 2015 were enrolled in 36 Italian centres. The primary endpoint was the number of patients with any appropriate implantable cardioverter-defibrillator (ICD) interventions during 12-month follow-up. The secondary endpoint comprised death from any cause and appropriate ICD interventions. At replacement, 214 (64.5%) patients had a left ventricular ejection fraction ≤ 35% and 138 (41.6%) patients had a secondary prevention indication for ICD. Seventy (21.1%) patients had no longer indication to ICD therapy. During a median follow-up period of 406.5 (362-533) days, VT/VF requiring therapy delivery occurred in 57 (17%) patients, specifically in 7% of those who no longer had an ICD indication. On multivariate analysis, number of criteria for ICD replacement independently predicted appropriate ICD intervention during follow-up [hazard ratio (HR) = 1.62, 95% confidence interval (CI) 1.07-2.46; log-rank P = 0.02]. The combined endpoint of death from any cause or appropriate ICD therapy occurred in 76 (23%) patients. Only NYHA class remained associated with this combined endpoint (HR = 1.97, 95% CI 1.23-3.14; P = 0.005). The DECODE registry showed the 'real-world' experience of CRT-D recipients approaching device replacement, in which 7% of patients who no longer had an indication for ICD therapy experienced appropriate ICD interventions.

Increased Hospitalizations and OverallHealthcare Utilization in PatientsReceivingImplantable Cardioverter-Defibrillator Shocks Compared With Antitachycardia Pacing.

The purpose of this study was to evaluate the effect of these therapies on healthcare utilization in a large patient cohort. Antitachycardia pacing (ATP) terminates ventricular tachycardia and avoids delivery of high-voltage shocks. Few data exist on the impact of shocks on healthcare resource utilization compared with ATP. PROVIDE (Programming Implantable Cardioverter Defibrillators in Patients With Primary Prevention Indication) was a prospective study of patients who received an implantable cardioverter-defibrillator (ICD) for primary prevention at 97 U.S. centers (2008 to 2010). We categorized the PROVIDE patients by the type of therapy delivered:notherapy, ATP only, or at least 1 shock. All ICD therapies, hospitalizations, and deaths were adjudicated. Cumulativecardiac hospitalizations, risk of all-cause death or cardiac hospitalization, and annual costs were comparedbetween groups. Of the 1,670 patients in PROVIDE, followed up for 18.1 ± 7.6 months, 1,316 received no therapy, 152 had ATPonly, and 202 received at least 1 shock. Patients receiving no therapy and those receiving only ATP had a lowercumulative hospitalization rate and were at lower risk for death or hospitalization (hazard ratio: 0.33 [p< 0.001] and 0.33 [p< 0.002], respectively). The cost of hospitalization was $2,874 per patient-year (95% confidence interval:$877 to $5,140; p= 0.002) higher for those receiving at least 1 shock than for those who received ATP only. There was no difference in outcomes or cost between patients receiving only ATP and those without therapy. Among patients implanted with an ICD for primary prevention, those who received only ATP therapyhad reduced hospitalizations, mortality, and cost compared with those who received at least 1 high-voltage shockandhad equivalent outcomes to patients who did not require any therapy. (Programming Implantable CardioverterDefibrillators in Patients With Primary Prevention Indication [PROVIDE]; NCT00743522).

Web-Based Intervention to Improve Implantable Cardioverter Defibrillator Patients' Shock-Related Anxiety and Quality of Life: A Randomized Controlled Trial.

In spite of its effectiveness, implantable cardioverter defibrillator (ICD) patients face psychological problems such as shock-related anxiety due to device shocks. The aim of this study was to evaluate whether a web-based intervention program for ICD patients would reduce shock-related anxiety and improve quality of life compared with usual care. This was a randomized controlled trial study including a total of 76 patients. Data were collected using Turkish versions of the Florida Shock Anxiety Scale and Short Form Health Survey (SF-36) at 0 (baseline), 3, and 6 months. Following intervention, there was a significant decrease in shock anxiety levels of patients and a statistically significant increase in social functioning, role-physical, mental health, vitality, and bodily pain subdimensions of SF-36. While no statistically significant difference was found between groups in terms of summary scores of SF-36, our results suggest that web-based interventions can be useful for ICD patients.

Impact of Moderate to Severe Chronic Kidney Disease for Long Term Survival of Implantable Cardioverter Defibrillator Patients in Taiwan

Summary Background The influence of renal impairment on long-term mortality in Taiwanese patients with an ICD was uncertain. The aim of our study was to examine the impact of moderate to severe CKD on outcome in patients with ICD implantation for secondary prevention in Taiwan. Methods From 2005 to 2013, patients who underwent ICD implantation who were survivors of sudden cardiac arrest or unstable hemodynamics due to ventricular arrhythmia at a single medical center were included in this registry. We divided the patients into two groups, group 1 with estimated glomerular filtration rates (eGFRs) of ≥60 mL/(min⋅1.73 cm2) and group 2 with eGFRs of Results 84 consecutive patients were enrolled in this registry. The mean age of the patients was 62.7 ± 13.2 years, and 54.8% were male. The patients of group 2 were older (mean age: 66.4 vs. 56.2 years) and had worse renal function (42 ± 12.3 vs. 89.0 ± 18.5 mL/(min⋅1.73 cm2)). They more often had hypertension (56.5% vs. 31.6%), diabetes mellitus (52.2% vs. 15.8%), and previous hospitalization for congestive heart failure as comorbidity (71.7% vs. 28.9%). During the mean follow-up duration of 952 days, 19 patients (22.6%) died. After adjustment for the parameters, eGFRs Conclusion Moderate to severe CKD is independently associated with increased mortality in Taiwanese patients who underwent ICD implantation for secondary prevention.

Ventricular Tachycardia with ICD Shocks: When to Medicate and When to Ablate.

Ventricular tachycardia occurrence in implantable cardioverter defibrillator (ICD) patients may result in shock delivery and is associated with increased morbidity and mortality. In addition, shocks may have deleterious mechanical and psychological effects. Prevention of ventricular tachycardia (VT) recurrence with the use of antiarrhythmic drugs or catheter ablation may be warranted. Antiarrhythmic drugs are limited by incomplete efficacy and an unfavorable adverse effect profile. Catheter ablation can be effective but acute complications and long-term VT recurrence risk necessitating repeat ablation should be recognized. A shared clinical decision process accounting for patients' cardiac status, comorbidities, and goals of care is often required. There are four published randomized trials of catheter ablation for sustained monomorphic VT (SMVT) in the setting of ischemic heart disease; there are no randomized studies for non-ischemic ventricular substrates. The most recent trial is the VANISH trial which randomly allocated patients with ICD, prior infarction, and SMVT despite first-line antiarrhythmic drug therapy to catheter ablation or more aggressive antiarrhythmic drug therapy. During 28months of follow-up, catheter ablation resulted in a 28% relative risk reduction in the composite endpoint of death, VT storm, and appropriate ICD shock (p=0.04). In a subgroup analysis, patients having VT despite amiodarone had better outcomes with ablation as compared to increasing amiodarone dose or adding mexiletine. There is evidence for the effectiveness of both catheter ablation and antiarrhythmic drug therapy for patients with myocardial infarction, an implantable defibrillator, and VT. If sotalol is ineffective in suppressing VT, either catheter ablation or initiation of amiodarone is a reasonable option. If VT occurs despite amiodarone therapy, there is evidence that catheter ablation is superior to administration of more aggressive antiarrhythmic drug therapy. Early catheter ablation may be appropriate in some clinical situations such as patients presenting with relatively slow VT below ICD detection, electrical storms, hemodynamically stable VT, or in very selected patients with left ventricular assist devices. The optimal first-line suppressive therapy for VT, after ICD implantation and appropriate programming, remains to be determined. Thus far, there has not been a randomized controlled trial to compare catheter ablation to antiarrhythmic drug therapy as a first-line treatment; the VANISH-2 study has been initiated as a pilot to examine this question.