Insertable cardiac monitor-guided early intervention to reduce atrial fibrillation burden following catheter ablation: Study design and clinical protocol (ICM-REDUCE-AF trial).

BACKGROUND: Percutaneous catheter ablation (CA) to achieve pulmonary vein isolation is an effective treatment for drug-refractory paroxysmal and persistent atrial fibrillation (AF). However, recurrence rates after a single AF ablation procedure remain elevated. Conventional management after CA ablation has mostly been based on clinical AF recurrence. However, continuous recordings with insertable cardiac monitors (ICMs) and patient-triggered mobile app transmissions post-CA can now be used to detect early recurrences of subclinical AF (SCAF). We hypothesize that early intervention following CA based on personalized ICM data can prevent the substrate progression that promotes the onset and maintenance of atrial arrhythmias. METHODS: This is a randomized, double-blind (to SCAF data), single-tertiary center clinical trial in which 120 patients with drug-refractory paroxysmal or persistent AF are planned to undergo CA with an ICM. Randomization will be to an intervention arm (n = 60) consisting of ICM-guided early intervention based on SCAF and patient-triggered mobile app transmissions versus a control arm (n = 60) consisting of a standard intervention protocol based on clinical AF recurrence validated by the ICM. Primary endpoint is AF burden, which will be assessed from ICMs at 15 months post-AF ablation. Secondary endpoints include healthcare utilization, functional capacity, and quality of life. CONCLUSION: We believe that ICM-guided early intervention will provide a novel, personalized approach to post-AF ablation management that will result in a significant reduction in AF burden, healthcare utilization, and improvements in functional capacity and quality of life.

Design and characteristics of the prophylactic intra-operative ventricular arrhythmia ablation in high-risk LVAD candidates (PIVATAL) trial.

BACKGROUND: The use of a Left Ventricular Assist Device (LVAD) in patients with advanced heart failure refractory to optimal medical management has progressed steadily over the past two decades. Data have demonstrated reduced LVAD efficacy, worse clinical outcome, and higher mortality for patients who experience significant ventricular tachyarrhythmia (VTA). We hypothesize that a novel prophylactic intra-operative VTA ablation protocol at the time of LVAD implantation may reduce the recurrent VTA and adverse events postimplant. METHODS: We designed a prospective, multicenter, open-label, randomized-controlled clinical trial enrolling 100 patients who are LVAD candidates with a history of VTA in the previous 5 years. Enrolled patients will be randomized in a 1:1 fashion to intra-operative VTA ablation (n = 50) versus conventional medical management (n = 50) with LVAD implant. Arrhythmia outcomes data will be captured by an implantable cardioverter defibrillator (ICD) to monitor VTA events, with a uniform ICD programming protocol. Patients will be followed prospectively over a mean of 18 months (with a minimum of 9 months) after LVAD implantation to evaluate recurrent VTA, adverse events, and procedural outcomes. Secondary endpoints include right heart function/hemodynamics, healthcare utilization, and quality of life. CONCLUSION: The primary aim of this first-ever randomized trial is to assess the efficacy of intra-operative ablation during LVAD surgery in reducing VTA recurrence and improving clinical outcomes for patients with a history of VTA.

Present and Future of Interventional Treatment of Resistant Hypertension.

The increasing prevalence of hypertension, a significant cause of disability and premature death throughout the world, is a major public health concern. This is especially true for the subset of patients who suffer from resistant hypertension, which is associated with a fourfold greater risk of cardiovascular events as compared to those hypertensive patients able to achieve target blood pressure. Though quite daunting in number and ill effect, hypertension remains the most common and the most important modifiable risk factor for coronary heart disease, congestive heart failure, peripheral vascular disease, stroke, and chronic kidney disease. Therefore, the ongoing development of novel therapies for the management of hypertension is of utmost importance. This review evaluates the present and future of interventional treatment of resistant hypertension, most of which remains investigational and warrants critical assessment.

Factors Associated With Smoking Cessation Attempts in Asthmatics.

Asthma is a common disorder affecting about 8% of adults in the U.S. Smoking is one factor that is associated with exacerbations of the disease. Somewhat surprisingly, the smoking prevalence among asthmatics is about the same as for the general population. It would be helpful to understand the demographic characteristics associated with those asthmatics who are smokers and who attempt to quit in order to better design approaches to help with cessation. This study examined the data from the 2012 Behavior Risk Factor Surveillance System (BRFSS) Asthma Call-Back Survey (ACBS), specifically demographic data such as gender, education, race/ethnicity, employment and others, to see if there are common characteristics in those asthmatics who attempt smoking cessation. We found that the only two statistically significant demographic characteristics were education and race. However, about two-thirds of those who made an attempt had had an episode of asthma in the past year and were more likely to have sought emergency care for asthma. These findings may help design better programs to help those patients with asthma who smoke.

Cardiac resynchronization therapy and ventricular tachyarrhythmia burden.

BACKGROUND: Cardiac resynchronization therapy-defibrillator (CRT-D) may reduce the incidence of first ventricular tachyarrhythmia (VTA) in patients with heart failure (HF) and left bundle branch block (LBBB). OBJECTIVE: The purpose of this study was to assess the effect of CRT-D on VTA burden in LBBB patients. METHODS: We included 1281 patients with LBBB from MADIT-CRT (Multicenter Automatic Defibrillator Implantation Trial-Cardiac Resynchronization Therapy). VTA was defined as any treated or monitored sustained ventricular tachycardia (VT ≥180 bpm) or ventricular fibrillation (VF). Life-threatening VTA was defined as VT ≥200 bpm or VF. VTA recurrence was assessed using the Andersen-Gill model. RESULTS: During a mean follow-up of 2.5 years, 964 VTA episodes occurred in 264 patients (21%). The VTA rate per 100 person-years was significantly lower in the CRT-D group compared with the implantable cardioverter-defibrillator (ICD) group (20 vs 34; P <.01). Multivariate analysis demonstrated that CRT-D treatment was associated with a 32% risk reduction for VTA recurrence (hazard ratio 0.68; 95% confidence interval 0.57-0.82; P <.001), 57% risk reduction for recurrent life-threatening VTA, 54% risk reduction for recurrent appropriate ICD shocks, and 25% risk reduction for the combined endpoint of VTA and death. The effect of CRT-D on VTA burden was consistent among all tested subgroups but was more pronounced among patients in New York Heart Association functional class I. Landmark analysis showed that at 2 years, the cumulative probability of death subsequent to year one was highest (16%) among patients who had ≥2 VTA events during their first year. CONCLUSION: In patients with LBBB and HF, early intervention with CRT-D reduces mortality, VTA burden, and frequency of multiple appropriate ICD shocks. VTA burden is a powerful predictor of subsequent mortality.

Device-Directed Therapy for Resistant Hypertension.

Hypertension remains a significant risk factor for an array of diseases despite advancements in pharmacotherapy. Patients with resistant hypertension who do not respond to conventional medical treatments and lifestyle modifications are especially at risk for poor health outcomes. With the increasing awareness of resistant hypertension, ever-evolving research efforts continue to focus on innovative interventions, including renal denervation, median nerve stimulation, and baroreceptor activation therapy. This article reviews the current evidence and summarizes previous clinical trials for each of these interventions.