Use of triple-site ventricular pacing in a patient with severe congestive heart failure and atrial fibrillation.

Cardiac resynchronization therapy (CRT) has become an accepted treatment for selected patients with drug-resistant heart failure. Data for patients in atrial fibrillation (AF) remains limited but suggests benefit in these patients too. We report the case of an 82-year-old patient with heart failure, VVIR permanent pacemaker, and permanent AF who had an upgrade to triple-site CRT implantation with good clinical response. Triple-site ventricular pacing may enhance the chance of response and LV reverse remodeling and should be considered in AF patients undergoing CRT implantation

Letter by Jeilan et al regarding article, Longitudinal strain delay index by speckle tracking imaging: a new marker of response to cardiac resynchronization therapy .

We read with interest the recent article by Lim et al.1 This article demonstrated a strong correlation between a novel longitudinal strain delay index and left ventricular end-systolic volume reduction in both ischemic and nonischemic patients. The principle outlined by the authors is that an increased longitudinal strain delay index requires both dyssynchrony (defined in their article as a discrepancy between the time of end-systolic contraction and the time to peak strain) and residual contractility. Their concept elegantly considers the problem of cardiac resynchronization therapy (CRT) nonresponse in heart failure patients who have myocardial segments with delayed contraction due to scarred or akinetic segments. The index appears to address some of the limitations of time delay indices that do not take account of residual myocardial contractility. Patients with a high longitudinal strain delay index (dyssynchronous and contractile) are more likely to respond to CRT than are patients with a lower index (synchronous, akinetic, or both). In the authors’ model, an absolute discrepancy between the time of end-systolic contraction and the time to peak strain is 2 sided. Broadly speaking, resynchronization therapy works by preexciting the areas of latest activation in the dyssynchronous left ventricle. This traditional understanding of CRT-responsive dyssynchrony would suggest that peak strain in the dyssynchronous target segments should be delayed and occur after aortic valve closure (postsystolic segments).2–3 However, the proposed strain delay index also includes “presystolic segments” (peak strain occurring in segments before aortic valve closure) within an averaging calculation. Intuitively, it is difficult to understand why CRT may address this type of presystolic dyssynchrony. It would be useful to see whether data that eliminate these presystolic, earlier-contracting segments from the analysis or incorporate a measure of the variability of delay (eg, standard deviation) across the 16 segments studied within the data set might affect or improve the index’s performance. Also, the authors did not describe the effect of CRT on this index. Although CRT’s effect was not the remit of their article, it would be interesting to use these data to evaluate the differences in changes (pre- and post-CRT) to the longitudinal strain delay index score among responders and nonresponders

Ganglionic Plexus Ablation During Pulmonary Vein Isolation - Predisposing to Ventricular Arrhythmias?

Catheter ablation is increasingly used to treat patients with atrial fibrillation (AF). Ablation of ganglionic plexi is often performed to reduce vagal innervation and has been shown to confer a better long-term outcome in terms of AF recurrence. We report a case of a patient having AF ablation with a profound vagal response, suggesting ganglionic plexus ablation, who subsequently developed ventricular fibrillation after programmed ventricular stimulation. Reduced vagal modulation is known to predispose to ventricular arrhythmias and vagal denervation following AF ablation may predispose to ventricular arrhythmias and requires further study

A systematic review of the spectrum of cardiac arrhythmias in Sub-Saharan Africa

Major structural cardiovascular diseases are associated with cardiac arrhythmias, but their full spectrum remains unknown in sub-Saharan Africa (SSA), which we addressed in this systematic review. Atrial fibrillation/atrial flutter (AF/AFL) prevalence is 16–22% in heart failure, 10–28% in rheumatic heart disease, 3–7% in cardiology admissions, but <1% in the general population. Use of oral anticoagulation is heterogenous (9–79%) across SSA. The epidemiology of sudden cardiac arrest/death is less characterized in SSA. Cardiopulmonary resuscitation is challenging, owing to low awareness and lack of equipment for life-support. About 18% of SSA countries have no cardiac implantable electronic devices services, leaving hundreds of millions of people without any access to treatment for advanced bradyarrhythmias, and implant rates are more than 200-fold lower than in the western world. Management of tachyarrhythmias is largely non-invasive (about 80% AF/AFL via rate-controlled strategy only), as electrophysiological study and catheter ablation centers are almost non-existent in most countries

Docosahexaenoic Acid Therapy of Experimental Ischemic Stroke

We examined the neuroprotective efficacy of docosahexaenoic acid (DHA), an omega-3 essential fatty acid family member, in acute ischemic stroke; studied the therapeutic window; and investigated whether DHA administration after an ischemic stroke is able to salvage the penumbra. In each series described below, SD rats underwent 2 h of middle cerebral artery occlusion (MCAo). In series 1, DHA or saline was administered i.v. at 3, 4, 5, or 6 h after stroke. In series 2, MRI was conducted on days 1, 3 and 7. In series 3, DHA or saline was administered at 3 h, and lipidomic analysis was conducted on day 3. Treatment with DHA significantly improved behavior and reduced total infarct volume by a mean of 40% when administered at 3 h, by 66% at 4 h, and by 59% at 5 h. Total lesion volumes computed from T2-weighted images were reduced in the DHA group at all time points. Lipidomic analysis showed that DHA treatment potentiates neuroprotectin D1 (NPD1) synthesis in the penumbra 3 days after MCAo. DHA administration provides neurobehavioral recovery, reduces brain infarction and edema, and activates NPD1 synthesis in the penumbra when administered up to 5 h after focal cerebral ischemia in rats

Rationale and study design of the MINERVA study: Multicentre Investigation of Novel Electrocardiogram Risk markers in Ventricular Arrhythmia prediction-UK multicentre collaboration

Introduction The purpose of this study is to assess the ability of two new ECG markers (Regional Repolarisation Instability Index (R2I2) and Peak Electrical Restitution Slope) to predict sudden cardiac death (SCD) or ventricular arrhythmia (VA) events in patients with ischaemic cardiomyopathy undergoing implantation of an implantable cardioverter defibrillator for primary prevention indication. Methods and analysis Multicentre Investigation of Novel Electrocardiogram Risk markers in Ventricular Arrhythmia prediction is a prospective, open label, single blinded, multicentre observational study to establish the efficacy of two ECG biomarkers in predicting VA risk. 440 participants with ischaemic cardiomyopathy undergoing routine first time implantable cardioverter-defibrillator (ICD) implantation for primary prevention indication are currently being recruited. An electrophysiological (EP) study is performed using a non-invasive programmed electrical stimulation protocol via the implanted device. All participants will undergo the EP study hence no randomisation is required. Participants will be followed up over a minimum of 18 months and up to 3 years. The first patient was recruited in August 2016 and the study will be completed at the final participant follow-up visit. The primary endpoint is ventricular fibrillation or sustained ventricular tachycardia >200 beats/min as recorded by the ICD. The secondary endpoint is SCD. Analysis of the ECG data obtained during the EP study will be performed by the core lab where blinding of patient health status and endpoints will be maintained. Ethics and dissemination Ethical approval has been granted by Research Ethics Committees Northern Ireland (reference no. 16/NI/0069). The results will inform the design of a definitive Randomised Controlled Trial (RCT). Dissemination will include peer reviewed journal articles reporting the qualitative and quantitative results, as well as presentations at conferences and lay summaries

Systematic, early rhythm control strategy for atrial fibrillation in patients with or without symptoms:the EAST-AFNET 4 trial

AIMS: Clinical practice guidelines restrict rhythm control therapy to patients with symptomatic atrial fibrillation (AF). The EAST-AFNET 4 trial demonstrated that early, systematic rhythm control improves clinical outcomes compared to symptom-directed rhythm control. METHODS AND RESULTS: This prespecified EAST-AFNET 4 analysis compared the effect of early rhythm control therapy in asymptomatic patients (EHRA score I) to symptomatic patients. Primary outcome was a composite of death from cardiovascular causes, stroke, or hospitalization with worsening of heart failure or acute coronary syndrome, analyzed in a time-to-event analysis. At baseline, 801/2633 (30.4%) patients were asymptomatic [mean age 71.3 years, 37.5% women, mean CHA(2)DS(2)-VASc score 3.4, 169/801 (21.1%) heart failure]. Asymptomatic patients randomized to early rhythm control (395/801) received similar rhythm control therapies compared to symptomatic patients [e.g. AF ablation at 24 months: 75/395 (19.0%) in asymptomatic; 176/910 (19.3%) symptomatic patients, P = 0.672]. Anticoagulation and treatment of concomitant cardiovascular conditions was not different between symptomatic and asymptomatic patients. The primary outcome occurred in 79/395 asymptomatic patients randomized to early rhythm control and in 97/406 patients randomized to usual care (hazard ratio 0.76, 95% confidence interval [0.6; 1.03]), almost identical to symptomatic patients. At 24 months follow-up, change in symptom status was not different between randomized groups (P = 0.19). CONCLUSION: The clinical benefit of early, systematic rhythm control was not different between asymptomatic and symptomatic patients in EAST-AFNET 4. These results call for a shared decision discussing the benefits of rhythm control therapy in all patients with recently diagnosed AF and concomitant cardiovascular conditions (EAST-AFNET 4; ISRCTN04708680; NCT01288352; EudraCT2010-021258-20)

Contributing factors concerning inconsistencies in persistent atrial fibrillation ablation outcomes

Background: We investigated current clinical methods for complex fractionated atrial electrogram (CFAE) classification during persistent atrial fibrillation (persAF). In particular, factors that directly influence the low reproducibility of CFAE-guided ablation outcomes in persAF therapy, such as inconsistencies in automated CFAE classification performed by different systems, the co-existence of different types of atrial electrograms (AEGs), and insufficient AEG duration for CFAE detection. Methods: 797 bipolar AEGs were exported from NavX (St. Jude Medical) from 18 persAF patients undergoing pulmonary vein isolation and roof line ablation (PVI+RL). CFE-Mean, CFE-StdDev and peak-to-peak were exported from NavX, while the interval confidence level, average and shortest complex interval – as defined by CARTO (Biosense Webster) – were calculated offline using a validated MATLAB script. Sample entropy, dominant frequency and organization index were also calculated offline. Results: First, we show that CFAE classification varies for the same individual, depending on the commercial system being used. Revised thresholds were found for the indices calculated by each system to minimize the differences in automated CFAE detection performed independently by them. Second, our results show that some AEGs are affected by PVI+RL in persAF, while others remain unaffected by it. Different types of AEGs might correlate with distinct underlying persAF mechanisms. Multivariate analysis using the multiple descriptors measured from the AEGs effectively discriminated the different types of AEGs. Finally, we show that consecutive AEGs with 2.5 s resulted in different ablation target identification using the CARTO criterion, which would affect the ablation strategy and contribute to conflicting outcomes in AEGguided ablation in persAF. Our results suggest that CARTO should consider AEGs with longer duration to measure CFAEs. Conclusions: A thorough re-evaluation of the definition of CFAE is necessary in order to refine the identification of critical atrial regions responsible for the perpetuation of the arrhythmia in patients with persAF