“Atrial Fibrillation, the Epidemic of Our Time” was the first portion of a multi-part session titled “Pharmacological and Interventional Options for Stroke Prevention in Atrial Fibrillation.” The introduction, titled “Multifaceted Approaches to Atrial Fibrillation: From Drugs to Ablation to Left Atrial Appendage Closure,” was delivered by Vivek Y. Reddy, MD, professor of medicine in cardiology at Mount Sinai Medical Center. According to Dr Reddy, amiodarone is the most effective drug for maintaining sinus rhythm in atrial fibrillation (AF). The newest agent, dronedarone, is more effective than placebo, but it is not yet known how it compares with the other medications. The 2012 ESC/EHRA guideline update indicates that medication selection should be based on presence or absence of structural heart disease and medication side effect profile. If evidence of LVH exists, dronedarone is recommended first. In patients with coronary heart disease, sotalol is recommended first. Amiodarone is the only drug recommended if heart failure exists.
According to the literature, catheter ablation is more effective in this population than drugs. Currently, the goal is pulmonary vein isolation to place a series of lesions that will make a ring of scar tissue to prevent impulses from entering the atrium. Dr Reddy reviewed treatment algorithm recommendations for medication versus ablation. According to Dr Reddy, it is thought that when ablation fails, it is due to PV reconnection (ie, the ring is not complete). More recent studies are suggesting that this rate of PV reconnection is improving. Lastly, Dr Reddy described left atrial appendage (LAA) closure for stroke prophylaxis. Four-year data indicate that appendage closure is superior to warfarin closure for the end point of reducing stroke.
The next presentation was “Profile of Patients with Atrial Fibrillation in 2013: From the Highly Symptomatic Athlete to the Asymptomatic 85-Year-Old” by Mintu Turakhia, MD, MAS, director of EP at the Palo Alto VA Health Care System and instructor at Stanford University School of Medicine. According to Dr Turakhia, published trials and observational studies do not represent many patients with newly detected AF who are seen in practice, and he presented 3 case examples. He stated that rhythm control is effective for symptomatic patients, and guidelines now recommend a low threshold to anticoagulate based on high-sensitivity risk scores, although the benefit remains uncertain. He stated that there is a high level of misclassification with CHADS2, which is based on old data of old patients, and that there has been a shift in treatment threshold. Lastly, he noted, in device-detected, the majority of ischemic strokes are not preceded by AF, which could challenge assumptions of etiology and rationale for therapy.
Taya V. Glotzer, MD, director of cardiac research at the Hackensack University Medical Center, delivered the final presentation of the session, “Silent Atrial Fibrillation: An Under-Appreciated Threat.” Dr Glotzer discussed the relationship between device-detected AF and stroke. She reviewed the literature, which suggests that regardless of AF burden, the risk of thromboembolic events still increases. Dr Glotzer wondered if silent, device-detected AF might be another risk factor to add to the CHA2DS2VASc score to make a determination of the risk/benefit of anticoagulation therapy. “Ongoing studies will shed more light on these dilemmas,” she said.