Experts Release Consensus Statement on Catheter and Surgical Ablation of Atrial Fibrillation
The Heart Rhythm Society, in joint partnership with heart societies from around the world, issued an international consensus statement that provides a state-of-the-art review of the indications, techniques, and outcomes of catheter and surgical ablation of atrial fibrillation (AF). This document is a complete and comprehensive revision of the 2012 statement.
“The rate of advancement in the tools, techniques, and outcomes of AF ablation continues to increase at a rapid pace. Our writing group worked together to revise the current recommendations to address the medical advancements that have really evolved over the last five years,” said Hugh Calkins, MD, Nicholas J. Fortuin, MD, Professor of Cardiology and Director of the Electrophysiology Laboratory and Arrhythmia Service at the Johns Hopkins Hospital in Baltimore. “It is our hope that this document can help improve patient care by providing a foundation for everyone involved in the care of AF patients, including clinicians who perform catheter or surgical ablations.”
For the first time, the writing group, comprising 60 experts from international organizations, addressed the issue of catheter ablation of AF in select asymptomatic patients. The group also addressed the issues of AF ablation as first-line therapy, the role of AF ablation in patients with heart failure, anticoagulation recommendations for patients undergoing ablation therapy, and the role of AF ablation in subgroups of patients not well represented in clinical trials. Recommendations pertinent to the design of clinical trials in the field of AF ablation and the reporting of outcomes, including relevant definitions, were also offered.
The final decision regarding care of a patient should be made by health care providers and their patients in light of all the circumstances presented by the patient, according to the authors. The document was published in the online edition of HeartRhythm, the official journal of the Heart Rhythm Society.
Long-Term Use of Aspirin Does Not Lower Risk of Stroke in Some Patients With Atrial Fibrillation
Using long-term aspirin therapy to prevent strokes among patients who are considered to be at low risk for stroke may not be effective as previously thought.
Patients with atrial fibrillation (AF) who received a catheter ablation and were at low risk of stroke did not benefit from long-term aspirin therapy, but were at risk of higher rates of bleeding, compared with patients who received no therapy at all.
“When AF patients are considered low risk for stroke, physicians often treat them with aspirin rather than stronger anticoagulants to further lower that risk,” said Jared Bunch, MD, Director of Heart Rhythm Research at the Intermountain Medical Center Heart Institute in Salt Lake City. “What was unknown was if aspirin was a safe and effective stroke prevention treatment after an ablation in lower-risk AF patients. Traditionally, lower-risk AF patients have been treated with aspirin without significant supportive data.”
Dr. Bunch and his team investigated the impact of long-term use of aspirin in 4,124 low-risk patients with AF who underwent catheter ablation. During a three-year period, those who were on aspirin had a significantly higher risk for gastrointestinal bleeding and genitourinary bleeding, compared with those on warfarin or those who were untreated.
“In both the general and medical communities, aspirin therapy is perceived to reduce risks,” said Dr. Bunch. “It is easy to prescribe, and it is available worldwide over the counter. There has always been little evidence to support its use for stroke prevention in AF patients. This study continues to show that aspirin has little to no benefit for stroke prevention in AF patients, and when used in low-risk patients, it significantly increases a patient’s bleeding risk.”
Artificial Intelligence Automatically Detects Atrial Fibrillation
The Apple Watch’s heart rate sensor, when paired with an artificial intelligence-based algorithm, can detect atrial fibrillation (AF). The research uses a deep neural network (DNN) based on photoplethysmographic (PPG) sensors commonly found in smart watches.
The study enrolled 6,158 users of Cardiogram for Apple Watch into the University of California, San Francisco (UCSF) Health eHeart Study. Data from those participants—including 139 million heart rate measurements and 6,338 mobile ECGs—were used to train a DNN to automatically distinguish AF from normal heart rhythm.
The DNN was validated against a cohort of 51 patients scheduled to undergo cardioversion. Each patient wore an Apple Watch for 20 minutes before and after cardioversion. With a 12-lead ECG as a reference standard, the DNN correctly detected AF with an accuracy of 97%, a sensitivity of 98.04%, and a specificity of 90.20%, which were higher than those of previously validated algorithms for the detection of AF.
“Our results show that common wearable trackers like smartwatches present a novel opportunity to monitor, capture, and prompt medical therapy for AF without any active effort from patients,” said senior author Gregory M. Marcus, MD, Endowed Professor of AF Research and Director of Clinical Research for the Division of Cardiology at UCSF. “While mobile technology screening will not replace more conventional monitoring methods, it has the potential to successfully screen those at an increased risk and lower the number of undiagnosed cases of AF.”
Delayed Use of Blood Thinners for Atrial Fibrillation Increases Risk of Dementia
Dementia rates increase when anticoagulation treatment is delayed for patients with atrial fibrillation. A large-scale study included more than 76,000 patients with atrial fibrillation with no prior history of dementia who were treated with an antiplatelet or warfarin.
Researchers studied patients from the time of their atrial fibrillation diagnosis to actual start of an antiplatelet agent or anticoagulation therapy. Patients were then grouped into two categories: those who received immediate treatment (started less than 30 days after diagnosis) and those who received delayed treatment (started after one year).
Using the CHADS2 VASc score to predict stroke risks and identify those at highest risk of cognitive decline with a delay in therapy, researchers found that the risk of dementia in low-risk patients was 30% higher for those who received delayed treatment, and a significant 136% higher for high-risk patients.
Researchers also found that when the time period of delays was analyzed as a spectrum including less than 30 days, 31 days to one year, one to three years, and longer than three years, the risk of dementia increased as the delays in warfarin initiation increased.
“Our results reinforce the importance of starting anticoagulation treatment as early as possible after a patient is diagnosed with atrial fibrillation,” said Jared Bunch, MD, Director of Heart Rhythm Research at the Intermountain Medical Center Heart Institute in Salt Lake City.