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Purpose of Review: Catheter-based ablation for atrial fibrillation is a useful and effective form of rhythm-control therapy for symptomatic patients. This article reviews the 'real-world' experience on the outcomes, complications, and costs of atrial fibrillation ablation., Recent Findings: Currently, real-world outcomes of atrial fibrillation ablation are derived from retrospective analysis of administrative databases or prospective registries from selected centers and patients. The rate of atrial fibrillation recurrence was reported to be as high as 60% and the rate of repeat ablation ranged from ≈10 to 18% within 1 year after ablation. All-cause hospitalizations after atrial fibrillation ablation were frequent, at up to ≈30% within 1 year and with up to half of them related to atrial fibrillation recurrence or repeat procedures. Rates of periprocedural complications were relatively low (≈3%). Female sex was associated with higher risk of complications such as bleeding, vascular injury, and tamponade. Markov models examining the cost-effectiveness of ablation yielded favorable results when success rates of more than 70% were assumed with long time horizons (>5 years)., Summary: The real-world outcomes of atrial fibrillation ablation are sobering. Confirmation of these findings with prospective, population-based, minimally biased studies is needed. There is a critical need to delineate the downstream economic impact of atrial fibrillation ablation on society to justify its continued delivery and growth.

Purpose of Review: Pulmonary vein reconnection leading to recurrence of atrial arrhythmias after pulmonary vein isolation (PVI) for atrial fibrillation remains a significant challenge. A number of adjunctive measures during PVI have been used to attempt to reduce pulmonary vein reconnection and recurrence of atrial arrhythmias. We performed a systematic review of the literature and meta-analysis of studies evaluating the efficacy of adjunctive measures used during PVI in reducing recurrent atrial arrhythmias., Recent Findings: Our literature search found four interventions that met the prespecified definition of adjunctive measure: adenosine testing post-PVI, contact force-guided PVI, pacing inexcitability of the ablation line during PVI and additional ablation based on the computed tomography thickness of the pulmonary vein-left atrial appendage ridge. Sixteen studies enrolling 3507 patients met all inclusion and exclusion criteria. PVI performed with adjunctive measures was shown to reduce the 1-year recurrence rate of atrial arrhythmias. The point estimate for the combined relative risk of atrial arrhythmia recurrence was 0.56 [95% confidence interval (CI): 0.43-0.73; P value <0.001] in the PVI with adjunctive measures group., Summary: PVI for atrial fibrillation assisted by adjunctive measures results in clinically significant reduction of recurrent atrial arrhythmias. Additional research is required to assess the relative efficacy of individual or combined adjunctive strategies used during PVI for atrial fibrillation.

Purpose of Review: Risks associated with exposure to ionizing radiation in patients undergoing electrophysiology procedures and interventional cardiac electrophysiologists performing these procedures are a serious concern. Strategies to reduce radiation exposure are of obvious importance. In addition, interventional cardiac electrophysiologists have to perform procedures wearing heavy lead protection for prolonged periods, making them prone to cervical and lumbar spinal injuries., Recent Findings: Recently developed technologies, such as low-exposure radiographic imaging, novel radiographic imaging protection systems, nonfluoroscopic mapping systems using image integration, and remote catheter manipulation systems have been successful in reducing ionizing radiation exposure in the electrophysiology laboratory. The efficacy and safety of these technologies are being evaluated in clinical trials. In addition, economic analyses are being performed to evaluate these novel systems. The use of nonweight-bearing radiation protection devices and ergonomic design of the electrophysiology laboratory aim to reduce the incidence of occupational injuries in interventional cardiac electrophysiologists., Summary: There is need for ongoing development and evaluation of new technologies to minimize exposure to ionizing radiation during electrophysiologic procedures. In addition, ergonomic planning of the electrophysiology laboratory and training of interventional cardiac electrophysiologists are crucial to occupational injury prevention.

Purpose of Review: Catheter ablation for atrial fibrillation is an effective rhythm-control therapy for selected patients. Currently, it is unknown whether maintenance of sinus rhythm after atrial fibrillation ablation can reduce one's stroke risk. If so, this may potentially obviate the need to treat patients with long-term oral anticoagulation (OAC). This article reviews the available evidence and areas of uncertainty pertaining to this question., Recent Findings: To date, no randomized trial data exist on this topic. Analyses from health administrative databases and observational registries suggested that atrial fibrillation patients who underwent catheter ablation had lower risk of stroke when compared with those who did not. Among patients who maintained sinus rhythm after ablation, low rates of stroke (<0.7% per year) were observed even after discontinuation of OAC therapy. These findings raise the possibility that successful catheter ablation may lower one's stroke risk to a point at which long-term OAC therapy is not obligatory., Summary: Whether successful atrial fibrillation ablation reduces one's stroke risk is unknown. Low stroke risks were reported by observational studies in patients who maintained sinus rhythm after ablation despite OAC cessation. High-quality, randomized trial data are needed to provide clarity on this key unanswered question.

Purpose of Review: To review the management of ventricular arrhythmias in patients with heart failure secondary to reduced ejection fraction (HFrEF)., Recent Findings: Recurrent ventricular arrhythmias and automatic implantable cardioverter defibrillator (AICD) shocks are responsible for significant mortality and morbidity in patients with HFrEF. Antiarrhythmic drugs and catheter ablation are the main treatment options. Frequent premature ventricular contractions (PVCs; >10,000-20,000/24-h period) are being recognized as a cause of cardiomyopathy and suboptimal response to cardiac resynchronization therapy (CRT). Patients with ventricular assist devices (VADs) have frequent ventricular tachyarrhythmias resulting in increased morbidity and mortality. Such patients may need continuation of active ICD therapy and adjunctive catheter ablation., Summary: There is a pressing need to develop new antiarrhythmic drugs to treat patients with recurrent AICD shocks. The effectiveness of catheter ablation as first-line therapy for preventing ventricular arrhythmias and recurrent AICD shocks needs to be directly compared with amiodarone. Ventricular tachyarrhythmias are common in CRT patients and patients with VADs. Frequent PVCs may result in a reversible form of HFrEF.

Purpose of Review: Sarcoidosis is a granulomatous disease of unclear cause and variable presentation. Cardiac involvement can result in life-threatening conditions including heart block, ventricular tachycardia, sudden cardiac death, and heart failure. There is no consensus on the diagnosis and management of cardiac sarcoidosis and a practical update is needed to provide clinicians with guidance., Recent Findings: Three recent studies have described cardiac manifestations as the first presentation of sarcoidosis. In one study, cardiac sarcoidosis was found to be the underlying cause in 19% of adults aged less than 55 years presenting with new onset unexplained atrioventricular block. Also, there are increasing reports of patients with isolated cardiac sarcoidosis (i.e., without sarcoid in other organs). Finally, advances in imaging have enhanced our ability to detect myocardial involvement and perhaps follow response to treatment., Summary: Cardiac sarcoidosis should be considered in patients aged less than 55 years presenting with unexplained atrioventricular block and in patients with idiopathic cardiomyopathy and sustained ventricular tachycardia. Much remains to be learned about the condition, including the role of steroids and devices in treatment, and the place of advanced imaging in following the response to treatment. Collaborative multicenter studies are required to answer these important clinical questions.

Purpose of Review: Cardiac resynchronization therapy (CRT) can reduce morbidity and mortality in patients with heart failure. However, a proportion of patients do not respond to CRT. This review addresses important clinical questions regarding patient selection for CRT., Recent Findings: Three recent large randomized trials show that CRT reduces morbidity and mortality in patients with New York Heart Association (NYHA) functional class II heart failure. Observational studies and a recent meta-analysis suggest that patients with NYHA III heart failure and atrial fibrillation may benefit from CRT. However, atrioventricular node ablation should be considered in this population to ensure greater than 92% biventricular pacing. Data from clinical trials do not support the use of CRT in patients with baseline right bundle branch block (RBBB)., Summary: Careful selection of CRT candidates is vital to improve patient outcomes and reduce exposure to unnecessary complications. This review summarizes recent data on the selection of CRT candidates, with emphasis on patients with NYHA I and II heart failure, atrial fibrillation and RBBB.

Purpose of Review: Atrial fibrillation is the most common clinical arrhythmia. Current treatment strategies are far from optimal. One new research direction is to target the atrial fibrillation substrate and to examine whether drugs can produce atrial structural and/or electrophysiological remodeling and whether this results in a reduction in atrial fibrillation burden., Recent Findings: Two prospective randomized studies have shown that the addition of an angiotensin converting enzyme inhibitor or an angiotensin receptor blocker to amiodarone reduces the recurrence rate of atrial fibrillation after electrical cardioversion. There are ten completed prospective clinical trials with atrial fibrillation as a secondary endpoint or assessed in post-hoc analysis. Five of these studies have reported a positive impact of angiotensin converting enzyme inhibitors or angiotensin receptor blockers on atrial fibrillation burden. A meta-analysis showed that active drugs reduced the overall risk of development of atrial fibrillation by 28%. Patients in the heart failure trials obtained most benefit from these drugs (relative risk reduction 44%, P = 0.07)., Summary: The initial basic science and clinical trial data suggest that modulation of the renin angiotensin system may be an effective treatment for atrial fibrillation. The following, however, remain to be clarified: do these drugs have a clinically meaningful impact on atrial fibrillation burden; if there is an impact, is it similar in all atrial fibrillation patients or just in certain subsets; do angiotensin converting enzyme inhibitors and angiotensin receptor blockers have similar benefits; and is there a role for aldosterone antagonists?

Purpose of Review: Cardiac resynchronization therapy improves quality of life, exercise performance, left ventricular ejection fraction, and reduces heart failure hospitalizations and mortality in patients with New York Heart Association class III or IV congestive heart failure and intraventricular conduction delay. A number of key clinical research questions remain, perhaps most importantly the issue of why apparently suitable patients do not respond to cardiac resynchronization therapy. These issues are also relevant to patients who do respond to cardiac resynchronization therapy as potentially their response might be further increased. This article will review the data regarding the frequency of the problem of non-response to cardiac resynchronization therapy and then discuss the postulated reasons and potential solutions., Recent Findings: Rates of non-response to cardiac resynchronization therapy are often quoted as 20-30%, but a critical analysis of the data would suggest the true non-responder rate can be estimated as perhaps 40-50%. The data indicate that on a population basis non-response is multi-factorial and the extent of mechanical dyssynchrony, left ventricular pacing site and cause of congestive heart failure are likely to be important. Ongoing research is exploring the utility of various techniques for quantifying mechanical dyssynchrony and the potential benefits of targeted left ventricular lead placement and post-implant optimization., Summary: Cardiac resynchronization therapy is a major breakthrough in treatment for advanced congestive heart failure patients. There is substantial rate of non-response to this therapy, however, and research is exploring various ways to increase the response to the technique.