Randomised trial of effect of amiodarone on mortality in patients with left-ventricular dysfunction after recent myocardial infarction: EMIAT. European Myocardial Infarct Amiodarone Trial Investigators

Adverse events in different administration routes of amiodarone: a pharmacovigilance study based on the FDA adverse event reporting system

Background

Arrhythmias are prevalent cardiac disorders with significant impacts on patient quality of life and mortality. Amiodarone, a class III antiarrhythmic agent, is widely used to manage both atrial and ventricular arrhythmias due to its efficacy in prolonging the cardiac action potential and its multiple antiarrhythmic properties. While clinical trials have highlighted the safety and efficacy of amiodarone, there is limited real-world data on adverse events (AEs) associated with different administration routes. This study aims to address this gap by utilizing the U.S. Food and Drug Administration's Adverse Event Reporting System (FAERS) to investigate the spectrum and timing of AEs related to amiodarone administration through disproportionality analysis and stratification methods.

Methods

Data from the FAERS database were analyzed using disproportionality analysis and reporting odds ratio (ROR) methods for comparative analysis, and the Weibull distribution for time-to-adverse-event analysis. The study examined data from 2004 through the first quarter of 2024 to analyze adverse event signals and the time of occurrence between intravenous and oral amiodarone administration.

Results

A total of 16,749 records of adverse reactions associated with amiodarone were identified. Among these, 2,412 events were related to intravenous amiodarone, and 8,220 events were related to oral amiodarone. The analysis revealed that cardiac and hepatic AEs were more common with intravenous administration, while pulmonary and thyroid-related AEs were more frequent with oral administration. Furthermore, the onset of adverse reactions varied significantly between the routes. The Weibull distribution analysis showed a median onset time of 5 days for intravenous administration compared to 74 days for oral administration. Both routes exhibited early failure-type signals, indicating a decreasing risk of AEs over time.

Conclusion

Amiodarone exhibits varying adverse drug reactions and onset times across different routes of administration. Clinicians should carefully consider these differences when selecting the administration route to balance the risks of adverse reactions with therapeutic benefits.

Effects of SZV-2649, a new multiple ion channel inhibitor mexiletine analogue

The antiarrhythmic and cardiac electrophysiological effects of SZV-2649 that contains a 2,6-diiodophenoxy moiety but lacks the benzofuran ring system present in amiodarone, were studied in mammalian cell line, rat and dog cardiac preparations. SZV-2649 exerted antiarrhythmic effects against coronary artery occlusion/reperfusion induced ventricular arrhythmias in rats and in acetylcholine- and burst stimulation induced atrial fibrillation in dogs. SZV-2649 inhibited hERG and GIRK currents in HEK cells (IC50: 342 and 529 nM, respectively). In canine ventricular myocytes, SZV-2649 (10 µM) decreased the densities of IKr, and Ito outward and INaL and ICaL inward currents. The compound (2.5-10 µM) elicited Class IB type Vmax reducing and Class III type action potential duration prolonging effects in dog right ventricular muscle preparations. In canine atrial muscle, SZV-2629 (2.5-10 µM) moderately prolonged action potential duration and this effect was greatly augmented in preparations pretreated with 1 µM carbachol. In conclusion, SZV-2649, has antiarrhythmic effects based on its multiple ion channel blocking properties. Since its chemical structure substantially differs from that of amiodarone, it is expected that SZV-2649 would exhibit fewer adverse effects than the currently used most effective multichannel inhibitor drug amiodarone and may be a promising molecule for further development.

Effect of perioperative intravenous amiodarone on cardioversion of atrial fibrillation early after video-assisted thoracoscopic surgical ablation: Study protocol for a double-blind randomized controlled trial

Introduction

Video-assisted thoracoscopic surgical (VATS) ablation is widely performed in surgical areas to treat atrial fibrillation (AF), which is minimally invasive and highly effective. Amiodarone, known as a class III antiarrhythmic agent, has the greatest potential to maintain sinus rhythm of AF. At present, few studies focused on the efficacy of perioperative intravenous amiodarone in the VATS ablation of AF. Therefore, the trial is designed to investigate the effect of perioperative amiodarone infusion on cardioversion of AF early after VATS ablation.

Methods

and analysis: This will be a prospective, randomized, double-blind, controlled trial. The trial is to enroll 182 patients aged 18–70 years who will undergo VATS ablation of AF. All eligible participants will be randomly allocated to either the amiodarone or placebo group by using the block randomization in a 1:1 ratio. The primary endpoint will be freedom from atrial arrhythmias 24 h after the VATS procedure and be assessed using the Kaplan-Meier method. All data will be analyzed in accordance with the intention-to-treat principle.

Discussion

The clinical trial has been designed to investigate the efficacy of perioperative intravenous amiodarone on cardioversion of AF early after VATS ablation. We are hoping to demonstrate that perioperative infusion of amiodarone could improve the maintenance of sinus rhythm 24 h after VATS ablation.

Ravichandran A, Bhat G, Al Ahmad A, Natale A, Di Biase L, Slaughter MS, Lakkireddy D. Amiodarone Use and All-Cause Mortality in Patients With a Continuous-Flow Left Ventricular Assist Device

Background

Atrial and ventricular arrhythmias are commonly encountered in patients with advanced heart failure, with amiodarone being the most commonly used antiarrhythmic drug in continuous‐flow left ventricular assist device (CF‐LVAD) recipients. The purpose of this study was to assess the impact of amiodarone use on long‐term all‐cause mortality in ptients with a CF‐LVAD.

Methods and Results

A retrospective multicenter study of CF‐LVAD was conducted at 5 centers including all CF‐LVAD implants from 2007 to 2015. Patients were stratified based on pre–CF‐LVAD implant amiodarone use. Additional use of amiodarone after CF‐LVAD implantation was also evaluated. Primary outcome was all‐cause mortality during long‐term follow‐up. Kaplan‐Meier curves were used to assess survival outcomes. Multivariable Cox regression was used to identify predictors of outcomes. Propensity matching was done to address baseline differences. A total of 480 patients with a CF‐LVAD (aged 58±13 years, 81% men) were included. Of these, 170 (35.4%) were on chronic amiodarone therapy at the time of CF‐LVAD implant, and 310 (64.6%) were not on amiodarone. Rate of all‐cause mortality over the follow‐up period was 32.9% in the amiodarone group compared with 29.6% in those not on amiodarone (P=0.008). Similar results were noted in the propensity‐matched group (log‐rank, P=0.04). On multivariable Cox regression analysis, amiodarone use at baseline was independently associated with all‐cause mortality (hazard ratio, 1.68 [95% CI, 1.1–2.5]; P=0.01).

Conclusions

Amiodarone use was associated with significantly increased rates of all‐cause mortality in CF‐LVAD recipients. Earlier interventions for arrhythmias to avoid long‐term amiodarone exposure may improve long‐term outcomes in CF‐LVAD recipients and needs further study.

Pharmacologic Management for Ventricular Arrhythmias: Overview of Anti-Arrhythmic Drugs

Ventricular arrhythmias (Vas) are a life-threatening condition and preventable cause of sudden cardiac death (SCD). With the increased utilization of implantable cardiac defibrillators (ICD), the focus of VA management has shifted toward reduction of morbidity from VAs and ICD therapies. Anti-arrhythmic drugs (AADs) can be an important adjunct therapy in the treatment of recurrent VAs. In the treatment of VAs secondary to structural heart disease, amiodarone remains the most well studied and current guideline-directed pharmacologic therapy. Beta blockers also serve as an important adjunct and are a largely underutilized medication with strong evidentiary support. In patients with defined syndromes in structurally normal hearts, AADs can offer tailored therapies in prevention of SCD and improvement in quality of life. Further clinical trials are warranted to investigate the role of newer therapeutic options and for the direct comparison of established AADs.

Incidence and predictors of sudden cardiac arrest in the immediate post-percutaneous coronary intervention period for ST-elevation myocardial infarction: a single-center study

BACKGROUND

Data on the incidence, predictors, and outcomes of sudden cardiac arrest (SCA) in the immediate post-percutaneous coronary intervention (PCI) period for ST-elevation myocardial infarction (STEMI) are limited.

OBJECTIVES

The study aimed to investigate the trends and predictors of SCA occurring within 48 h post PCI for STEMI.

METHODS

We systematically reviewed data from the electronic medical records of 403 patients who underwent PCI for STEMI between January 2014 and December 2019. Trends in the incidence of SCA 48 h post PCI for STEMI were assessed using the Cochrane-Armitage test. Multivariable logistic regression was used to determine the predictors of SCA within 48 h post PCI for STEMI.

RESULTS

Of the 403 patients who underwent PCI for STEMI, 44 (11%) had SCA within 48 h post PCI. The incidence of SCA within 48 h post PCI decreased from 22% in 2014 to 8% in 2019; P = 0.03. After adjusting for underlying confounding variables in the multivariable logistic regression models, out of hospital cardiac arrest [adjusted odds ratio (aOR), 23.9; confidence interval (CI), 10.2-56.1], left main coronary artery disease (aOR, 3.1; CI, 1.1-9.4), left main PCI (aOR, 6.6; CI: 1.4-31.7), new-onset heart failure (aOR, 2.0; CI, 4.3-9.4), and cardiogenic shock (aOR, 5.8; CI, 1.7-20.2) were statistically significant predictors of SCA within 48 h post PCI for STEMI.

CONCLUSION

We identified essential factors associated with SCA within 48 h post PCI for STEMI. Future studies are needed to devise effective strategies to decrease the risk of SCA in the early post-PCI period.

Mexiletine for ventricular arrhythmias in patients with chronic coronary syndrome: a cohort study

BACKGROUND

The pharmacological therapy of ventricular arrhythmias in patients with unsuccessful or not feasible catheter ablation and contraindication or inefficacy to amiodarone and beta-blockers, is controversial. The present study investigated the effectiveness and tolerability of mexiletine in patients with recurrent ventricular arrhythmias and ischaemic heart disease, when the conventional antiarrhythmic therapy failed.

METHODS

We enrolled all consecutive patients with unsuccessful/not feasible catheter ablation and ineffective/contraindicated amiodarone or beta-blockers, which started the mexiletine treatment for refractory ventricular tachycardia (VT) or ventricular fibrillation (VF) between January 2010 and January 2020. The primary endpoint was the total number of VT/VF episodes after the beginning of mexiletine therapy. The 2 secondary endpoints were the overall number of therapies released by implantable cardioverter-defibrillators (ICDs) and the discontinuation of the pharmacological therapy. The events occurring during the mexiletine treatment period were compared with those observed in a matched duration interval before the initiation of therapy.

RESULTS

Thirty-four consecutive patients (27 males, 79.4%; mean age 74.0 ± 9.5 years) with ischaemic heart disease were finally analysed. The median of mexiletine treatment was 26.5 months (interquartile range: 18.75-38.25 months). After the mexiletine start, VT/VF episodes and ICD interventions significantly decreased (respectively: 74 vs 33 episodes, p = 0.002; 116 vs 52 interventions, p = 0.02) in comparison with a matched period without mexiletine. Six patients (13.9%) discontinued the treatment because of severe side effects.

CONCLUSIONS

The treatment period following the mexiletine start was associated with a significant reduction of ventricular arrhythmias. The rate of side effects requiring dosage reduction or interruption was not neglectable.

OCT2013, an ischaemia-activated antiarrhythmic prodrug, devoid of the systemic side effects of lidocaine

BACKGROUND AND PURPOSE

Sudden cardiac death (SCD) caused by acute myocardial ischaemia and ventricular fibrillation (VF) is an unmet therapeutic need. Lidocaine suppresses ischaemia-induced VF, but its utility is limited by side effects and a narrow therapeutic index. Here, we characterise OCT2013, a putative ischaemia-activated prodrug of lidocaine.

EXPERIMENTAL APPROACH

The rat Langendorff-perfused isolated heart, anaesthetised rat and rat ventricular myocyte preparations were utilised in a series of blinded and randomised studies to investigate the antiarrhythmic effectiveness, adverse effects and mechanism of action of OCT2013, compared with lidocaine.

KEY RESULTS

In isolated hearts, OCT2013 and lidocaine prevented ischaemia-induced VF equi-effectively, but OCT2013 did not share lidocaine's adverse effects (PR widening, bradycardia and negative inotropy). In anaesthetised rats, i.v. OCT2013 and lidocaine suppressed VF and increased survival equi-effectively; OCT2013 had no effect on cardiac output even at 64 mg·kg^-1 i.v., whereas lidocaine reduced it even at 1 mg·kg^-1 . In adult rat ventricular myocytes, OCT2013 had no effect on Ca²⁺ handling, whereas lidocaine impaired it. In paced isolated hearts, lidocaine caused rate-dependent conduction slowing and block, whereas OCT2013 was inactive. However, during regional ischaemia, OCT2013 and lidocaine equi-effectively hastened conduction block. Chromatography and MS analysis revealed that OCT2013, detectable in normoxic OCT2013-perfused hearts, became undetectable during global ischaemia, with lidocaine becoming detectable.

CONCLUSIONS AND IMPLICATIONS

OCT2013 is inactive but is bio-reduced locally in ischaemic myocardium to lidocaine, acting as an ischaemia-activated and ischaemia-selective antiarrhythmic prodrug with a large therapeutic index, mimicking lidocaine's benefit without adversity.

The value of wearable cardioverter defibrillator in adult patients with recent myocardial infarction: Economic and clinical implications from a health technology assessment perspective

AIMS

Sudden cardiac death (SCD) causes high mortality and substantial societal burdens for healthcare systems (HSs). The risk of SCD is significantly increased in patients with reduced left ventricular ejection fraction after myocardial infarction (MI). Current guidelines recommend re-evaluation of cardioverter-defibrillator implantation 40 days post-MI, earliest. Medical therapy alone does not provide sufficient protection against SCD, especially in the first month post-MI, and needs time. Consequently, there is a gap in care of high-risk patients upon hospital discharge. The wearable cardioverter defibrillator (WCD) is a proven safe, effective therapy, which temporarily protects from SCD. Little information on WCD cost-effectiveness exists. We conducted this research to demonstrate the medical need of the device in the post-MI setting defining WCD cost-effectiveness.

METHODS & RESULTS

Based on a randomized clinical trials (RCTs) and Italian and international data, we developed a Markov-model comparing costs, patient survival, and quality-of-life, and calculated the Incremental Cost-Effectiveness Ratio (ICER) of a WCD vs. current standard of care in post-MI patients. The rather conservative base case analysis - based on the RCT intention-to-treat results - produced an ICER of €47,709 per Quality Adjusted Life Year (QALY) gained, which is far lower than the accepted threshold of €60,000 in the Italian National HS. The ICER per Life Year (LY) gained was €38,276.

CONCLUSION

WCD utilization in post-MI patients is clinically beneficial and cost-effective. While improving guideline directed patient care, the WCD can also contribute to a more efficient use of resources in the Italian HS, and potentially other HSs as well.

Oral procainamide as pharmacological treatment of recurrent and refractory ventricular tachyarrhythmias: A single-center experience

Background

Antiarrhythmic therapy for recurrent ventricular arrhythmias in patients who have undergone catheter ablation, and in whom amiodarone and/or beta-blockers were ineffective or contraindicated, is a controversial issue.

Objective

The present study sought to evaluate the efficacy and tolerability of oral procainamide in patients with recurrent ventricular arrhythmias when the standard therapy strategy had failed.

Methods

All patients treated with procainamide for recurrent ventricular tachycardia (VT) or ventricular fibrillation (VF) in our institution between January 2010 and May 2019 were enrolled. The primary endpoint was the total number of implantable cardioverter-defibrillator (ICD) interventions after the beginning of procainamide therapy. Secondary endpoints were the total number of VTs and VFs recorded on the ICDs' controls and discontinuation of therapy. The events occurring during procainamide treatment were compared with a matched-duration period before the initiation of therapy with procainamide. Patients therefore served as self-controls.

Results

A total of 34 consecutive patients (32 male, 94.1%; mean age 74.4 ± 9.7 years) were included in the retrospective analysis. The mean time of procainamide treatment was 12.9 ± 13.7 months (median 9 [2-20] months). The mean dose of procainamide was 1207 ± 487 mg/day. Procainamide therapy significantly decreased ICD interventions (median 5 [0-22.5] vs 15.5 [3-32.25], P < .05). Procainamide also decreased the total number of VT/VF episodes (median 5.5 [0.75-30] vs 19 [7.5-30], P < .05). Only 3 patients (8.8%) presented severe side effects (dyspnea or hypotension), requiring discontinuation of therapy.

Conclusion

Oral procainamide was associated with a significant decrease in ICD therapies and ventricular arrhythmias, showing an acceptable profile of tolerability.

Sudden cardiac death - a known unknown?

Sudden cardiac death (SCD) is a major medical, economic and social problem. The estimated annual number of SCDs is approximately 4 million cases worldwide. Approximately 50% of SCDs are unexpected first manifestations of cardiac disease. The survival rate after out-of-hospital cardiac arrest is low even in countries with the most advanced health care systems. It all emphasizes the importance of prevention, in which implantable cardioverter-defibrillators play a dominant role. However, our ability to recognize high-risk patients remains insufficient. Moreover, a declining rate of shockable rhythm as the initial recording has been reported in the last decades. Despite numerous SCD studies and undisputed progress, there are still many unanswered questions.

Ablation Versus Drug Therapy for Atrial Fibrillation in Racial and Ethnic Minorities

BACKGROUND

Rhythm control strategies for atrial fibrillation (AF), including catheter ablation, are substantially underused in racial/ethnic minorities in North America.

OBJECTIVES

This study sought to describe outcomes in the CABANA trial as a function of race/ethnicity.

METHODS

CABANA randomized 2,204 symptomatic participants with AF to ablation or drug therapy including rate and/or rhythm control drugs. Only participants in North America were included in the present analysis, and participants were subgrouped as racial/ethnic minority or nonminority with the use of National Institutes of Health definitions. The primary endpoint was a composite of death, disabling stroke, serious bleeding, or cardiac arrest.

RESULTS

Of 1,280 participants enrolled in CABANA in North America, 127 (9.9%) were racial and ethnic minorities. Compared with nonminorities, racial and ethnic minorities were younger with median age 65.6 versus 68.5 years, respectively, and had more symptomatic heart failure (37.0% vs 22.0%), hypertension (92.1% vs 76.8%, respectively), and ejection fraction <40% (20.8% vs 7.1%). Racial/ethnic minorities treated with ablation had a 68% relative reduction in the primary endpoint (adjusted hazard ratio [aHR]: 0.32; 95% confidence interval [CI]: 0.13-0.78) and a 72% relative reduction in all-cause mortality (aHR: 0.28; 95% CI: 0.10-0.79). Primary event rates in racial/ethnic minority and nonminority participants were similar in the ablation arm (4-year Kaplan-Meier event rates 12.3% vs 9.9%); however, racial and ethnic minorities randomized to drug therapy had a much higher event rate than nonminority participants (27.4% vs. 9.4%).

CONCLUSION

Among racial or ethnic minorities enrolled in the North American CABANA cohort, catheter ablation significantly improved major clinical outcomes compared with drug therapy. These benefits, which were not seen in nonminority participants, appear to be due to worse outcomes with drug therapy. (Catheter Ablation vs Anti-arrhythmic Drug Therapy for Atrial Fibrillation Trial [CABANA]; NCT00911508).

Chronic Amiodarone Use and the Risk of Cancer: A Systematic Review and Meta-analysis

Background

Observational studies have identified inconsistent associations between chronic use of amiodarone and cancer-related outcomes. We performed a systematic review and meta-analysis to evaluate cancer risk among patients receiving amiodarone.

Methods

We searched MEDLINE, Embase, and the Cochrane Central Register of Controlled Trials (CENTRAL) to May 1, 2020. We included randomized controlled trials (RCTs) with follow-up ≥2 years that compared amiodarone (any dose) to any comparator (placebo, active pharmacologic or interventional comparator, or usual care), and reported ≥1 outcome of interest. We contacted authors of published chronic amiodarone trials for potentially unreported cancer outcomes. The primary outcome was cancer incidence. Secondary outcomes were cancer-related death and site-specific cancers. We determined risk ratios and 95% confidence intervals using a fixed-effect model, and statistical heterogeneity using I². We conducted prespecified subgroup and sensitivity analyses for amiodarone indication, amiodarone dose, duration of therapy, and trial-level risk of bias.

Results

From 1439 articles, we included 5 RCTs (n = 4357). Mean follow-up duration ranged from 21 to 37 months. We included previously unpublished cancer outcome data from 1 RCT. Our primary outcome was not reported in any RCT. There was no significant difference in cancer-related death between amiodarone (1.69%) and the comparator (1.75%) (risk ratio 0.96, 95% confidence interval 0.57-1.63; I² = 0%). There were no significant interactions from our subgroup or sensitivity analyses.

Conclusions

Chronic amiodarone use did not increase cancer-related deaths. Data from RCTs do not support an increased risk of cancer-related harms with amiodarone use, and these concerns should not deter use of amiodarone when indicated.

Sudden death and its predictors in myocardial infarction survivors in an Indian population

Objective

This study was conducted to assess the incidence of sudden cardiac death (SCD) in post myocardial infarction patients and to determine the predictive value of various risk markers in identifying cardiac mortality and SCD.

Methods

Left ventricular function, arrhythmias on Holter and microvolt T wave alternans (MTWA) were assessed in patients with prior myocardial infarction and ejection fraction ≤ 40%. The primary outcome was a composite of cardiac death and resuscitated cardiac arrest during follow up. Secondary outcomes included total mortality and SCD.

Results

Fifty-eight patients were included in the study. Eight patients (15.5%) died during a mean follow-up of 22.3 ± 6.6 months. Seven of them (12.1%) had SCD. Among the various risk markers studied, left ventricular ejection fraction (LVEF) ≤ 30% (Hazard ratio 5.6, 95% CI 1.39 to 23) and non-sustained ventricular tachycardia (NSVT) in holter (5.7, 95% CI 1.14 to 29) were significantly associated with the primary outcome in multivariate analysis. Other measures, including QRS width, heart rate variability, heart rate turbulence and MTWA showed no association.

Conclusions

Among patients with prior myocardial infarction and reduced left ventricular function, the rate of cardiac death was substantial, with most of these being sudden cardiac death. Both LVEF ≤30% and NSVT were associated with cardiac death whereas only LVEF predicted SCD. Other parameters did not appear useful for prediction of events in these patients. These findings have implications for decision making for the use of implantable cardioverter defibrillators for primary prevention in these patients.

Wenn die Weste einige Nummern zu groß ist: Sinn und Unsinn der LifeVest bei Postinfarktpatienten

Die LifeVest ist eine tragbare Kardioverter-Defibrillator-Weste (WCD), die eine zeitlich limitierte diagnostische und therapeutische, nicht invasive Option für Patienten mit einem hohen Risiko für den plötzlichen Herztod (PHT) auf dem Boden von lebensbedrohlichen anhaltenden ventrikulären Tachyarrhythmien darstellt. Hierbei hat sich die LifeVest sowohl bei Patienten mit transienter höhergradiger linksventrikulärer Dysfunktion als auch bei Patienten zur Überbrückung bis zur endgültigen Versorgung mit einem implantierbaren Kardioverter-Defibrillator (ICD) in der klinischen Praxis etabliert. Unklar waren bislang die Effektivität und der zusätzliche Benefit der WCD innerhalb der ersten Wochen nach stattgehabtem Myokardinfarkt bei Patienten mit reduzierter linksventrikulärer Pumpfunktion. In der prospektiven, randomisierten und kontrollierten VEST-Studie konnte kein Zusatznutzen der WCD bezüglich der Verhinderung des PHT in dieser Patientengruppe aufgezeigt werden.

Comparable risk of recurrent ventricular tachyarrhythmias in implantable cardioverter-defibrillator recipients treated with single beta-blocker or combined amiodarone

This study sought to assess the prognostic impact of treatment with single beta-blocker (BB) compared to combined therapy with BB plus amiodarone (BB-AMIO) on recurrences of ventricular tachyarrhythmias in implantable cardioverter-defibrillator (ICD) recipients. A large retrospective registry was used including consecutive ICD recipients with index episodes of ventricular tachyarrhythmias from 2002 to 2016. Patients treated with BB were compared to patients treated with BB-AMIO. Kaplan-Meier and Cox regression analyses were applied for the evaluation of the primary end-point defined as first recurrences of ventricular tachyarrhythmias at five years. Secondary end-points comprised first appropriate ICD therapies, first cardiac rehospitalization and all-cause mortality at five years. Among 512 ICD recipients, 81% were treated with BB and 19% with BB-AMIO. BB and BB-AMIO were associated with comparable risk of first recurrences of ventricular tachyarrhythmias (46% vs. 43%; log rank P = .941; HR = 1.013; 95% CI 0.725-1.415; P = .941) and appropriate ICD therapies (35% vs. 37%; log rank P = .389; HR = 0.852; 95% CI 0.591-1.228; P = .390). BB was associated with decreased long-term all-cause mortality within an univariable analysis only (20% vs. 28%; log rank p = 0.023). In conclusion, BB and BB-AMIO were associated with comparable risks regarding recurrences of ventricular tachyarrhythmias at five years.

Cardiac arrhythmias in the emergency settings of acute coronary syndrome and revascularization: an European Heart Rhythm Association (EHRA) consensus document, endorsed by the European Association of Percutaneous Cardiovascular Interventions (EAPCI), and European Acute Cardiovascular Care Association (ACCA)

Despite major therapeutic advances over the last decades, complex supraventricular and ventricular arrhythmias (VAs), particularly in the emergency setting or during revascularization for acute myocardial infarction (AMI), remain an important clinical problem. Although the incidence of VAs has declined in the hospital phase of acute coronary syndromes (ACS), mainly due to prompt revascularization and optimal medical therapy, still up to 6% patients with ACS develop ventricular tachycardia and/or ventricular fibrillation within the first hours of ACS symptoms. Despite sustained VAs being perceived predictors of worse in-hospital outcomes, specific associations between the type of VAs, arrhythmia timing, applied treatment strategies and long-term prognosis in AMI are vague. Atrial fibrillation (AF) is the most common supraventricular tachyarrhythmia that may be asymptomatic and/or may be associated with rapid haemodynamic deterioration requiring immediate treatment. It is estimated that over 20% AMI patients may have a history of AF, whereas the new-onset arrhythmia may occur in 5% patients with ST elevation myocardial infarction. Importantly, patients who were treated with primary percutaneous coronary intervention for AMI and developed AF have higher rates of adverse events and mortality compared with subjects free of arrhythmia. The scope of this position document is to cover the clinical implications and pharmacological/non-pharmacological management of arrhythmias in emergency presentations and during revascularization. Current evidence for clinical relevance of specific types of VAs complicating AMI in relation to arrhythmia timing has been discussed.

Pharmacological management of atrial fibrillation in patients with heart failure with reduced ejection fraction: review of current knowledge and future directions

Introduction: Both heart failure with reduced ejection fraction (HFrEF) and atrial fibrillation (AF) independently cause significant morbidity and mortality. The two conditions commonly coexist and AF in the setting of HFrEF is associated with worse mortality, hospitalizations, and quality of life compared to HFrEF without AF. Despite the large burden of these conditions, there is no clear optimal management strategy for when they occur together.Areas covered: This review focuses on the pharmacological management of AF in HFrEF. Studies were identified through PubMed search of relevant keywords. The authors review key clinical trials that have influenced management strategies and guidelines. The authors focus on the classes of drugs used to treat AF for both rate and rhythm control strategies including beta-blockers, digoxin, amiodarone, and dofetilide. Additionally, the authors discuss select non-antiarrhythmic medications that affect AF in HFrEF. The authors highlight the strengths and weakness of the data supporting the use of these medications and suggest future directions.Expert opinion: The pharmacological treatment of AF in HFrEF will need further refinement alongside the emerging role of catheter ablation. Novel HF medications and antiarrhythmics offer new tools to prevent the development of AF, as well as for rate and rhythm control strategies.

Enhanced Inflammation is a Marker for Risk of Post-Infarct Ventricular Dysfunction and Heart Failure

Acute ST-segment elevation myocardial infarction (STEMI) activates inflammation that can contribute to left ventricular systolic dysfunction (LVSD) and heart failure (HF). The objective of this study was to examine whether high-sensitivity C-reactive protein (CRP) concentration is predictive of long-term post-infarct LVSD and HF. In 204 patients with a first STEMI, CRP was measured at hospital admission, 24 h (CRP24), discharge (CRPDC), and 1 month after discharge (CRP1M). LVSD at 6 months after discharge (LVSD6M) and hospitalization for HF in long-term multi-year follow-up were prospectively evaluated. LVSD6M occurred in 17.6% of patients. HF hospitalization within a median follow-up of 5.6 years occurred in 45.7% of patients with LVSD6M vs. 4.9% without LVSD6M (p < 0.0001). Compared to patients without LVSD6M, the patients with LVSD6M had higher CRP24 and CRPDC and persistent CRP1M ≥ 2 mg/L. CRP levels were also higher in patients in whom LVSD persisted at 6 months (51% of all patients who had LVSD at discharge upon index STEMI) vs. patients in whom LVSD resolved. In multivariable analysis, CRP24 ≥ 19.67 mg/L improved the prediction of LVSD6M with an increased odds ratio of 1.47 (p < 0.01). Patients with LVSD6M who developed HF had the highest CRP during index STEMI. Elevated CRP concentration during STEMI can serve as a synergistic marker for risk of long-term LVSD and HF.

Immunohistochemical expression of autophagosome markers LC3 and p62 in preneoplastic liver foci in high fat diet-fed rats

Nonalcoholic fatty liver disease (NAFLD) is characterized by excessive deposition of droplets in hepatocytes. Patients with NAFLD can be at risk for nonalcoholic steatohepatitis, which can lead to hepatocellular carcinoma. Autophagy is a cellular pathway that is crucial for survival and homeostasis, and which protects against pathophysiological changes like obesity and cancer. We determined the expression of autophagy markers in preneoplastic hepatic lesions and the effects of an autophagy repressor chloroquine (CQ) or inducer amiodarone (AM) in a steatosis-related hepatocarcinogenesis model. Male F344 rats were fed a control diet or high fat diet (HFD), and subjected to initiation and promotion steps with N-nitrosodiethylamine injection at week 0 and a partial hepatectomy at week 3. Several HFD-fed rats were administered 0.1% CQ and 0.5% AM in their drinking water during week 2 and 8. CQ and AM did not improve HFD-induced obesity. AM, but not CQ, significantly decreased the number of glutathione S-transferase placental form-positive preneoplastic liver foci in the liver. Autophagosome markers LC3 and the LC3-binding protein p62 were heterogeneously expressed in the preneoplastic foci. CQ might inhibit autophagy by significantly increased p62/LC3 ratio, while AM might have a potential of inducing autophagy by showing an increased gene expression of the autophagy regulator, Atg5. These results suggest that preneoplastic lesions express autophagosome markers and that AM might decrease steatosis-related early hepatocarcinogenesis by potentially inducing autophagy in HFD-fed rats, while inhibition of autophagy by CQ did not alter the hepatocarcinogenesis. However, an immunohistochemical trial revealed a technical limitation in detecting autophagosome markers because there were variations in each preneoplastic lesion.

A Novel Lipidomics-Based Approach to Evaluating the Risk of Clinical Hepatotoxicity Potential of Drugs in 3D Human Microtissues

The importance of adsorption, distribution, metabolism, excretion, and toxicity (ADMET) analysis is expected to grow substantially due to recent failures in detecting severe toxicity issues of new chemical entities during preclinical/clinical development. Traditionally, safety risk assessment studies for humans have been conducted in animals during advanced preclinical or clinical phase of drug development. However, potential drug toxicity in humans now needs to be detected in the drug discovery process as soon as possible without reliance on animal studies. The "omics", such as genomics, proteomics, and metabolomics, have recently entered pharmaceutical research in both drug discovery and drug development, but to the best of our knowledge, no applications in high-throughput safety risk assessment have been attempted so far. This paper reports an innovative method to anticipate adverse drug effects in an early discovery phase based on lipid fingerprints using human three-dimensional microtissues. The risk of clinical hepatotoxicity potential was evaluated for a data set of 22 drugs belonging to five different therapeutic chemical classes and with various drug-induced liver injury effect. The treatment of microtissues with repeated doses of each drug allowed collecting lipid fingerprints for five time points (2, 4, 7, 9, and 11 days), and multivariate statistical analysis was applied to search for correlations with the hepatotoxic effect. The method allowed clustering of the drugs based on their hepatotoxic effect, and the observed lipid impairments for a number of drugs was confirmed by literature sources. Compared to traditional screening methods, here multiple interconnected variables (lipids) are measured simultaneously, providing a snapshot of the cellular status from the lipid perspective at a molecular level. Applied here to hepatotoxicity, the proposed workflow can be applied to several tissues, being tridimensional microtissues from various origins.

Who Should Receive a Wearable Defibrillator Vest at Hospital Discharge?

PURPOSE OF REVIEW

To discuss the role of wearable cardioverter defibrillator (WCD) vests in preventing sudden cardiac death (SCD) in at-risk populations.

RECENT FINDINGS

The impact of randomized-controlled trials with implantable cardioverter-defibrillators (ICD) therapy is well established in randomized clinical trials in ischemic cardiomyopathy. Although the benefits are not as clear in non-ischemic cardiomyopathy, meta-analyses show significant mortality benefits from immediate electrical cardioversion strategies. The role of WCDs in at-risk populations in whom ICD therapy is temporarily not indicated is not as well-established. Smaller cohort trials have shown efficacy in patients with newly-diagnosed cardiomyopathy, requiring temporary ICD explantation, and others with less common indications for WCD therapy. The Vest Prevention of Early Sudden Death Trial was a landmark randomized control study seeking to examine the benefits of WCD therapy in at-risk population, and although the primary endpoint of reducing arrhythmic death was not reached, the structure of the trial and significant differences in total mortality make a compelling case for continued use of WCD therapies in our healthcare systems.

Arrhythmias in Patients ≥80 Years of Age: Pathophysiology, Management, and Outcomes

Advances in medical care have led to an increase in the number of octogenarians and even older patients, forming an important and unique patient subgroup. It is clear that advancing age is an independent risk factor for the development of most arrhythmias, causing substantial morbidity and mortality. Patients ≥80 years of age have significant structural and electrical remodeling of cardiac tissue; accrue competing comorbidities; react differently to drug therapy; and may experience falls, frailty, and cognitive impairment, presenting significant therapeutic challenges. Unfortunately, very old patients are under-represented in clinical trials, leading to critical gaps in evidence to guide effective and safe treatment of arrhythmias. In this state-of-the-art review, we examine the pathophysiology of aging and arrhythmias and then present the available evidence on age-specific management of the most common arrhythmias, including drugs, catheter ablation, and cardiac implantable electronic devices.

Anti-arrhythmic drug therapy in implantable cardioverter-defibrillator recipients

Implantable cardioverter-defibrillators (ICDs) have revolutionized the primary and secondary prevention of patients with ventricular arrhythmias. However, the adverse effects of appropriate or inappropriate shocks may require the adjunctive use of anti-arrhythmic drugs (AADs). Beta blockers are the cornerstone of pharmacological primary and secondary prevention of ventricular arrhythmias. In addition to their established efficacy at reducing the incidence of ventricular arrhythmias, beta-blockers are safe with few side effects. Amiodarone is superior to beta blockers and sotalol for the prevention of ventricular arrhythmia recurrence. However, long-term amiodarone use is associated with significant side effects that limit its utility. Sotalol and mexiletine are the main alternatives to amiodarone with a better side effect profile though they are less efficacious at preventing ventricular arrhythmia recurrence. Dofetilide, azimilide and ranolazine are emerging as therapeutic options for secondary prevention; more studies are needed to assess efficacy and safety in comparison to currently used agents. Beta blockers and amiodarone are the mainstay of therapy in patients experiencing electrical storm; their use reduces the frequency of ventricular arrhythmias and ICD intervention as well as affording time until catheter ablation can be considered.

Intra-hospital transport of critically ill patients with rapid response team and risk factors for cardiopulmonary arrest: A retrospective cohort study

INTRODUCTION

This study aimed to determine the occurrence rate and risk factors of cardiopulmonary arrest (CPA) during intra-hospital transport (IHT) among critically ill patients, accompanied by a rapid response team (RRT).

METHODS

We performed a retrospective cohort study in a 1300-bed tertiary-care teaching hospital. Data of all admitted patients transported within the hospital and accompanied by the RRT from October 2012 to May 2016 were included. We compared patients with CPA (+) and patients without CPA (-) to identify risk factors for CPA during transport.

RESULTS

Among 535 patients, CPA occurred in eight (1.5%) patients during IHT. There were no significant differences in age, sex, and comorbidities between groups. More patients in the CPA (+) group than in the CPA (-) group received manual ventilation during IHT (75% vs. 23.0%, p = 0.001). An increased risk of CPA (p<0.001) corresponded with a higher number of vasopressors used during IHT. In univariate logistic regression analysis, history of myocardial infarction (OR 10.7, 95% CI 2.4-50.5, p = 0.005), manual ventilation (OR 10.1, 95% CI 2.0-50.5, p = 0.005), and use of three or more vasopressors (OR 11.1, 95% CI 2.5-48.9, p = 0.001) were significantly associated with risk of CPA during RRT-led IHT.

CONCLUSIONS

Despite accompaniment by a specialized team such as the RRT, CPA can occur during IHT. History of myocardial infarction, manual ventilation with bag-valve mask, and the use of three or more vasopressors were independent risk factors of CPA during IHT of critically ill patients accompanied by the RRT.

Prognostic impact of beta-blocker compared to combined amiodarone therapy secondary to ventricular tachyarrhythmias

OBJECTIVE

The study sought to assess the prognostic impact of treatment with beta-blocker (BB) compared to combined BB plus amiodarone (BB-AMIO) on long-term survival in patients surviving ventricular tachyarrhythmias on admission.

BACKGROUND

Data regarding the prognostic outcome of patients presenting with ventricular tachyarrhythmias treated with BB and BB-AMIO is limited.

METHODS

A large retrospective registry was used including consecutive patients surviving index episodes of ventricular tachyarrhythmias from 2002 to 2016. Patients treated with BB were compared to patients with BB-AMIO. The primary prognostic endpoint was long-term all-cause death at 3 years. Kaplan-Meier, multivariable Cox regression and propensity score matching analyses were applied.

RESULTS

A total of 1354 patients was included, 85% treated with BB, 15% with BB-AMIO. Within the unmatched real-life cohort, uni- and multivariable Cox regression models revealed BB associated with improved long-term survival compared to BB-AMIO (univariable: HR = 0.550; p = 0.001, multivariable: HR = 0.712; statistical trend, p = 0.052). After propensity-score matching (n = 186 matched pairs), BB therapy was still associated with improved survival compared to BB-AMIO (mortality rate 18% versus 26%; log rank p = 0.042; HR = 0.634; 95% CI = 0.407-0.988; p = 0.044). Prognostic superiority of BB was mainly observed in patients with LVEF ≥ 35% (HR = 0.463; 95% CI = 0.215-0.997; p = 0.049) and in those without atrial fibrillation (non-AF) (HR = 0.415; 95% CI = 0.202-0.852; p = 0.017).

CONCLUSION

BB therapy is associated with improved secondary long-term prognosis compared to BB-AMIO in patients surviving index episodes of ventricular tachyarrhythmias.

Effect of Prophylactic Amiodarone Infusion on the Recurrence of Ventricular Arrhythmias in Out-of-Hospital Cardiac Arrest Survivors: A Propensity-Matched Analysis

Amiodarone is recommended for shock-refractory ventricular arrhythmia during resuscitation; however, it is unknown whether amiodarone is effective for preventing ventricular arrhythmia recurrence in out-of-hospital cardiac arrest (OHCA) survivors treated with targeted temperature management (TTM). We investigated the effectiveness of prophylactic amiodarone in preventing ventricular arrhythmia recurrence in OHCA survivors. Data of consecutive adult non-traumatic OHCA survivors treated with TTM between 2010 and 2016 were extracted from prospective cardiac arrest registries of four tertiary care hospitals. The prophylactic amiodarone group was matched in a 1:1 ratio by using propensity scores. The primary outcome was ventricular arrhythmia recurrence requiring defibrillation during TTM. Among 295 patients with an initially shockable rhythm and 149 patients with initially non-shockable-turned-shockable rhythm, 124 patients (27.9%) received prophylactic amiodarone infusion. The incidence of ventricular arrhythmia recurrence was 11.26% (50/444). Multivariate analysis showed prophylactic amiodarone therapy to be the independent factor associated with ventricular arrhythmia recurrence (odds ratio 1.95, 95% CI 1.04–3.65, p = 0.04), however, no such association was observed (odds ratio 1.32, 95% CI 0.57–3.04, p = 0.51) after propensity score matching. In this propensity-score-matched study, prophylactic amiodarone infusion had no effect on preventing ventricular arrhythmia recurrence in OHCA survivors with shockable cardiac arrest. Prophylactic amiodarone administration must be considered carefully.

Characteristics of hERG and hNav1.5 channel blockade by sulcardine sulfate, a novel anti-arrhythmic compound

Sulcardine sulfate (sulcardine) is a novel anti-arrhythmic compound, which blocks multiple channels and was shown to be safe and tolerated in clinical trials. The aim of the present study was to investigate the electrophysiological characteristics of sulcardine on the hERG and hNav1.5 channels. The hERG and hNav1.5 channels were heterologously stably expressed in human embryonic kidney 293 cells, and the effects of sulcardine on the hERG and hNav1.5 channels were recorded using the standard whole-cell patch-clamp technique. Sulcardine inhibited hERG channels in a concentration-dependent and reversible manner (IC₅₀ = 94.3 μM). In addition, sulcardine shifted the activation curve of hERG channels to more negative potentials. The relative block of sulcardine on hERG channels was close to zero at the time point corresponding to channel opening, which was achieved by applying a depolarizing voltage, and quickly increased afterward. Sulcardine inhibited hNav1.5 channels in a concentration-dependent and reversible manner (IC₅₀ = 15.0 μM) and shifted the inactivation curve of hNav1.5 channels to more negative potentials. The blockade of sulcardine on hNav1.5 channels was use-dependent. In conclusion, sulcardine is a potent hNav1.5 channel blocker with a mild inhibitory effect on hERG channels and preferentially binds to both hERG and hNav1.5 channels in the open and inactivated states rather than in the resting state.

[Clinical aspects of treatment with amiodarone]

Amiodarone has multiple and complex electrophysiological effects that render it a very effective antiarrhythmic drug for the treatment of both, supraventricular and ventricular arrhythmias. Proarrhythmic effects of amiodarone in patients with structural heart disease are rare. However, extracardiac adverse effects occurring in association with amiodarone treatment are frequent and feared. These adverse effects have usually been related to total amiodarone exposure (i. e., dose and duration of treatment). Parallel to a more frequent use of lower amiodarone maintenance doses (100-200 mg/day), the incidence of severe unwanted extracardiac side effects has decreased. High-dose maintenance regiments (daily dose ≥300 mg) are usually obsolete. This paper discusses recommendations regarding the monitoring of cardiac and extracardiac side effects of amiodarone. They need to be regarded by physicians using amiodarone to ensure long-term safety of amiodarone therapy.

Amiodarone is associated with adverse outcomes in patients with sustained ventricular arrhythmias upgraded to cardiac resynchronization therapy-defibrillators

INTRODUCTION

Amiodarone reduces recurrent ventricular tachyarrhythmias (VTA) but may worsen cardiovascular outcomes in heart failure (HF) patients. Cardiac resynchronization therapy (CRT) may also be antiarrhythmic. When patients with prior sustained VTA are upgraded to CRT defibrillators (CRT-D) from conventional implantable cardioverter-defibrillators (ICDs), should concomitant amiodarone be continued or is CRT's antiarrhythmic potential sufficient?

METHODS AND RESULTS

We identified 67 patients from a prospective CRT registry with spontaneous sustained VTA, New York Heart Association (NYHA) II-IV HF, and left bundle-branch block (LBBB) who were upgraded to CRT defibrillators from conventional ICDs. We compared changes in QRS duration and left ventricular ejection fraction (LVEF) pre- and post-CRT, time to death, transplant or ventricular assist device (VAD), and time to recurrent VTA therapies between 37 patients continuing amiodarone therapy and 30 amiodarone-naïve patients. Amiodarone-treated patients had worse renal function and a higher prevalence of prior VTA storm compared with amiodarone-naïve patients. After CRT, amiodarone-treated patients demonstrated less QRS narrowing (8 vs 20 ms; P = 0.021) and less LVEF improvement (-2.7 vs +5.2%; P = 0.006). Over 29 months, 31 (47%) patients died and 13 (20%) received transplant or VAD. Risk of death, transplant, or VAD was greater in amiodarone-treated than -naïve patients (corrected hazard ratio [HR], 2.14; 95% confidence interval [CI], 1.12-4.11; P = 0.022). Appropriate CRT-D therapies occurred in 37 (55%) patients; amiodarone use was not associated time to first therapy (HR, 1.13; 95% CI, 0.59-2.16; P = 0.72).

CONCLUSION

In patients with sustained VTA and LBBB upgraded from conventional ICDs to CRT defibrillators, concomitant amiodarone use is associated with less QRS narrowing, less LVEF improvement, greater risk of death, transplant, or VAD, and similar risk of recurrent VTA.

Controlled Release of Small Molecules for Cardiac Differentiation of Pluripotent Stem Cells

Induced pluripotent stem cells (iPSCs) have been shown to differentiate to functional cardiomyocytes (CM) with high efficiency through temporally controlled inhibition of the GSK3/Wnt signaling pathways. In this study, we investigated the ability of temporally controlled release of GSK3/Wnt small-molecule inhibitors to drive cardiac differentiation of iPSC without manual intervention. Porous silica particles were loaded with GSK3 inhibitor CHIR99021 or Wnt inhibitor IWP2, and the particles containing IWP2 were coated with 5 wt% poly(lactic-co-glycolic acid) 50:50 to delay release by ∼72 h. iPSCs reprogrammed through mRNA transfection were cultured with these particles up to 30 days. High-performance liquid chromatography suggests a burst release of CHIR99021 within the first 24 h and a delayed release of IWP2 after 72 h. Annexin V/propidium iodide staining did not show a significant effect on apoptosis or necrosis rates. Cultured cells upregulated both early (Nkx 2.5, Isl-1) and late (cTnT, MHC, Cx43) cardiac markers, assayed with a quantitative real-time polymerase chain reaction, and began spontaneous contraction at 3.0 ± 0.6 Hz at 15-21 days after the start of differentiation. CM had clear sarcomeric striations when stained for β-myosin heavy chain, and showed expression and punctate membrane localization of gap junction protein Connexin43. Calcium and voltage-sensitive imaging showed both action potential and calcium transients typical of immature CM. This study showed that the cardiac differentiation of pluripotent stem cells can be directed by porous silica vectors with temporally controlled release of small-molecule inhibitors. These results suggest methods for automating and eliminating variability in manual maintenance of inhibitor concentrations in the differentiation of pluripotent stem cells to CM.

Wearable Cardioverter-Defibrillator after Myocardial Infarction

BACKGROUND

Despite the high rate of sudden death after myocardial infarction among patients with a low ejection fraction, implantable cardioverter-defibrillators are contraindicated until 40 to 90 days after myocardial infarction. Whether a wearable cardioverter-defibrillator would reduce the incidence of sudden death during this high-risk period is unclear.

METHODS

We randomly assigned (in a 2:1 ratio) patients with acute myocardial infarction and an ejection fraction of 35% or less to receive a wearable cardioverter-defibrillator plus guideline-directed therapy (the device group) or to receive only guideline-directed therapy (the control group). The primary outcome was the composite of sudden death or death from ventricular tachyarrhythmia at 90 days (arrhythmic death). Secondary outcomes included death from any cause and nonarrhythmic death.

RESULTS

Of 2302 participants, 1524 were randomly assigned to the device group and 778 to the control group. Participants in the device group wore the device for a median of 18.0 hours per day (interquartile range, 3.8 to 22.7). Arrhythmic death occurred in 1.6% of the participants in the device group and in 2.4% of those in the control group (relative risk, 0.67; 95% confidence interval [CI], 0.37 to 1.21; P=0.18). Death from any cause occurred in 3.1% of the participants in the device group and in 4.9% of those in the control group (relative risk, 0.64; 95% CI, 0.43 to 0.98; uncorrected P=0.04), and nonarrhythmic death in 1.4% and 2.2%, respectively (relative risk, 0.63; 95% CI, 0.33 to 1.19; uncorrected P=0.15). Of the 48 participants in the device group who died, 12 were wearing the device at the time of death. A total of 20 participants in the device group (1.3%) received an appropriate shock, and 9 (0.6%) received an inappropriate shock.

CONCLUSIONS

Among patients with a recent myocardial infarction and an ejection fraction of 35% or less, the wearable cardioverter-defibrillator did not lead to a significantly lower rate of the primary outcome of arrhythmic death than control. (Funded by the National Institutes of Health and Zoll Medical; VEST ClinicalTrials.gov number, NCT01446965 .).

Catheter ablation of ventricular tachycardia in nonischemic cardiomyopathy

The number of patients with nonischemic cardiomyopathy (NICM) undergoing catheter ablation of ventricular tachycardia (VT) has increased by the years, however, there are no randomized studies of VT ablation in this population. Many studies have reported more mixed or inferior outcome after the ablation in patients with NICM as compared to in those with ischemic cardiomyopathy (ICM)-likely because of the heterogeneous VT substrates in each etiology. While, various ablation strategies for substrate modification in the setting of ICM, including low voltage area ablation, late potential abolition, and local abnormal ventricular activity elimination, have been well established, it is still unknown which ablation strategy is effective for prevention of recurrence VTs in NICM patients. Therefore, this review will highlight the recent progress made in VT ablation in patients with NICM.

Risk stratifiers for arrhythmic and non-arrhythmic mortality after acute myocardial infarction

The effective discrimination between patients at risk of Arrhythmic Mortality (AM) and Non-Arrhythmic Mortality (NAM) constitutes one of the important unmet clinical needs. Successful risk assessment based on Electrocardiography (ECG) records is greatly improved by the combination of different indices reflecting not only the pathological substrate but also the autonomic regulation of cardiac electrophysiology. This study assesses the cardiac risk stratification capacity of two new Heart Rate Variability (HRV) parameters, Breath Concurrence 6 (BC6) -sinusoidal RR variability of 6 heart beats per breath cycle- and Primary Ectopia (PE) -presence of early ventricular contractions of any etiology- together with the Deceleration Capacity (DC). While BC6 characterizes the response to physiological and pathophysiological stimuli, PE qualifies autonomic cardiac electrophysiology. The analysis of the European Myocardial Infarct Amiodarone Trial (EMIAT) database indicates that BC6 is related with the risk of Arrhythmic Mortality (AM) and PE with the risk of Non-Arrhythmic Mortality. BC6 is the only single parameter that significantly discriminates between AM and NAM. While the combination of BC6 and DC contributes to the identification of AM risk, PE together with DC improves the prediction of NAM in patients with severe ischemic heart disease.

Abdel-Daim M. Rhythm Versus Rate Control for Atrial Fibrillation: A Meta-analysis of Randomized Controlled Trials

Atrial fibrillation (AF) is a common, sustained tachyarrhythmia, associated with an increased risk of mortality and thromboembolic events. We performed this meta-analysis to compare the clinical efficacy of rate and rhythm control strategies in patients with AF in a meta-analysis framework. A comprehensive search of PubMed, OVID, Cochrane-CENTRAL, EMBASE, Scopus, and Web of Science was conducted, using relevant keywords. Dichotomous data on mortality and other clinical events were extracted and pooled as risk ratios (RRs), with their 95% confidence-interval (CI), using RevMan software (version 5.3). Twelve studies (8451 patients) were pooled in the final analysis. The overall effect-estimate did not favor rate or rhythm control strategies in terms of all-cause mortality (RR= 1.13, 95% CI [0.88, 1.45]), stroke (RR= 0.97, 95% CI [0.79, 1.20]), thromboembolism (RR= 1.06, 95% CI [0.64, 1.76]), and major bleeding (RR= 1.10, 95% CI [0.90, 1.35]) rates. These findings were consistent in AF patients with concomitant heart failure (HF). The rate of rehospitalization was significantly higher (RR= 0.72, 95% CI [0.57, 0.92]) in the rhythm control group, compared to the rate control group. In younger patients (<65 years), rhythm control was superior to rate control in terms of lowering the risk of all-cause mortality (p=0.0003), HF (p=0.003) and major bleeding (p=0.02). In older AF patients and those with concomitant HF, both rate and rhythm control strategies have similar rates of mortality and major clinical outcomes; therefore, choosing an appropriate strategy should consider individual variations, such as patient preferences, comorbidities, and treatment cost.

Lower In-Hospital Ventricular Tachyarrhythmia in Patients With Acute Myocardial Infarction Receiving Prior Statin Therapy

We evaluated whether prior statin therapy reduces in-hospital ventricular tachycardia/ventricular fibrillation (VT/VF) in percutaneous coronary intervention (PCI) patients with acute myocardial infarction (MI). Among the 1177 patients from the Acute Myocardial Infarction Registry-National Institutes of Health (KAMIR-NIH), 823 (70%) patients received prior statin therapy. Prior statin therapy was associated with a reduced risk of VT/VF events in both adjusted propensity score analysis (odds ratio [OR] 0.414, 95% confidence interval [CI], 0.198-0.865, P = .019) and adjusted inverse probability of treatment weight analysis (OR 0.463, 95% CI, 0.216-0.994, P = .048). The risk of in-hospital death did not differ significantly between those with or without prior statin therapy (hazard ratio [HR] 0.416, 95% CI, 0.112-1.548, P = .191). Major adverse cardiac events occurred in 116 (8.9%) patients during follow-up. Prior statin therapy was associated with a lower risk of major adverse cardiac events during the follow-up period (HR 0.486, 95% CI, 0.243-0.974, P = .042); however, this was mainly driven by reduced noncardiac death. Prior statin therapy might reduce the incidence of serious cardiac tachyarrhythmia, such as VT/VF, in patients with MI undergoing PCI. However, the reduction in VT/VF due to prior statin therapy did not improve short- and long-term clinical outcomes.

Amiodarone: A Newly Discovered Association with Bilateral Vestibulopathy

Background

Bilateral vestibulopathy (BVP) is a debilitating disorder characterized by the hypofunction of both vestibular end organs or nerves. The most frequent identifiable causes of BVP are ototoxic drug effects, infectious and autoimmune disorders. However, the majority of cases remain idiopathic. Very recently, the first discovery of a clinical case of Amiodarone-associated BVP has been reported.

Methods

An overview of the literature concerning the relation between amiodarone toxicity and BVP is presented and discussed.

Results

Older reports on amiodarone-induced symptoms of vertigo and gait instability lack a description of vestibular function test results. Recent evidence from retrospective studies including vestibular function testing in patients taking amiodarone have identified the drug as the hitherto unsuspected potential cause of a relatively large proportion of cases with “idiopathic” BVP.

Conclusion

Patients who receive amiodarone should be monitored with vestibular function testing in order to recognize potential adverse effects on the vestibular system and allow for an informed decision on possible drug reduction or withdrawal.

Team Management of the Ventricular Tachycardia Patient

Ventricular tachycardia is a common arrhythmia in patients with structural heart disease and heart failure, and is now seen more frequently as these patients survive longer with modern therapies. In addition, these patients often have multiple comorbidities. While anti-arrhythmic drug therapy, implantable cardioverter-defibrillator implantation and ventricular tachycardia ablation are the mainstay of therapy, well managed by the cardiac electrophysiologist, there are many other facets in the care of these patients, such as heart failure management, treatment of comorbidities and anaesthetic interventions, where the expertise of other specialists is essential for optimal patient care. A coordinated team approach is therefore essential to achieve the best possible outcomes for these complex patients.

Case Report of the Patient with Acute Myocardial Infarction: “From Flatline to Stent Implantation”

Asystole is a rare primary manifestation in the development of sudden cardiac death (SCD), and survival during cardiac arrest as the consequence of asystole is extremely low. The aim of our paper is to illustrate successful cardiopulmonary resuscitation (CPR) in patients with acute myocardial infarction (AMI) and rare and severe form of cardiac arrest - asystole. A very short time between cardiac arrest in acute myocardial infarction, which was manifested by asystole, and the adequate CPR measures that have been taken are of great importance for the survival of our patient.

After successful reanimation, the diagnosis of anterior wall AMI with ST segment elevation was established. The right therapeutic strategy is certainly the early primary percutaneous coronary intervention (PPCI). In less than two hours, after recording the “flatline” and successful reanimation, the patient was in the catheterization laboratory, where a successful PPCI of LAD was performed, after emergency coronary angiography. In the further treatment course of the patient, the majority of risk factors were corrected, except for smoking, which may be the reason for newly discovered lung tumor disease. Early recognition and properly applied treatment of CPR can produce higher rates of survival.

Have the Findings from Clinical Risk Prediction and Trials Any Key Messages for Safety Pharmacology?

Anti-arrhythmic drugs are a mainstay in the management of symptoms related to arrhythmias, and are adjuncts in prevention and treatment of life-threatening ventricular arrhythmias. However, they also have the potential for pro-arrhythmia and thus the prediction of arrhythmia predisposition and drug response are critical issues. Clinical trials are the latter stages in the safety testing and efficacy process prior to market release, and as such serve as a critical safeguard. In this review, we look at some of the lessons to be learned from approaches to arrhythmia prediction in patients, clinical trials of drugs used in the treatment of arrhythmias, and the implications for the design of pre-clinical safety pharmacology testing.

Clinical applications of QT/RR hysteresis assessment: A systematic review

BACKGROUND

QT/RR hysteresis (QT-hys) is an index of the time accommodation of ventricular repolarization to heart rate changes. This report comprehensively reviews studies addressing QT-hys as a biomarker of medical conditions.

METHODS

This is a secondary analysis of data from a recent systematic review pertaining to methods of assessment of QT-hys. Articles included in the former review were filtered in order to select original articles investigating the association of QT-hys with medical conditions in humans.

RESULTS

Nineteen articles fulfilled our inclusion criteria. Given the heterogeneity of the methods and investigated conditions, no pooled analysis of data could be implemented. QT-hys was mostly studied as a risk marker of severe arrhythmias, as a predictor of the long QT syndrome (LQTS) phenotypes and genotypes and as a marker of exercise-induced ischemia. An increased QT-hys appears to be implicated in arrhythmogenesis, although the evidence in this regard relies on few human studies. An augmented QT-hys was reported in the LQTS, predominantly in the LQT2 genotype, but conflicting results were obtained between studies using different methods of assessment. In addition, QT-hys appears to be a useful marker of stress-induced myocardial ischemia in patients suspected of coronary artery disease.

CONCLUSIONS

QT-hys evaluation has potential clinical utility in at least some clinical conditions. Further studies of the clinical validity of QT-hys assessment are warranted, particularly condition specific studies based on QT-hys evaluation methods that provide separate estimates of QT-hys and QT/RR dependency.

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

PURPOSE OF REVIEW

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.

RECENT FINDINGS

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 28 months 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.

Amiodarone-Induced Third Degree Atrioventricular Block and Extreme QT Prolongation Generating Torsade Des Pointes in Paroxysmal Atrial Fibrillation

Amiodarone is still the most potent antiarrhythmic drug in the prevention of life threatening ventricular arrhythmias and demonstrates a very low incidence of torsade de pointes. An unusual case of an 81-year-old woman who developed serious abnormalities of the conduction system of the heart and torsade des pointes during intravenous infusion of amiodarone for the treatment of paroxysmal atrial fibrillation is described. To the best of our knowledge, this is the first case showing an association of intravenous amiodarone-induced third degree atrioventricular block and extreme QT interval prolongation generating torsade des pointes in a patient with paroxysmal atrial fibrillation who required an implantable cardioverter-defibrillator. Currently, amiodarone is still one of the few remaining treatment options for the medical therapeutic management of serious ventricular arrhythmias and to reduce the incidence of atrial fibrillation without increasing mortality or sudden cardiac death rates in heart failure patients like our elderly present patient. Nevertheless, we have to keep in mind that intravenous amiodarone may generate serious abnormalities of the conduction system of the heart and lethal ventricular arrhythmias in certain patients.