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EP News: Clinical
EP News: Clinical N.A. Mark Estes III, MD, FHRS From the Tufts Medical Center, Boston, Massachusetts.
Catheter ablation vs medical rate control in atrial fibrillation and systolic dysfunction Prabhu et al (J Am Coll Cardiol 2017;Epub ahead of print; PMID 28855115) evaluated whether catheter ablation (CA) for atrial fibrillation (AF) could improve left ventricular systolic dysfunction (LVSD) compared with medical rate control (MRC) where the etiology of the LVSD was unexplained, apart from the presence of AF. This multicenter randomized clinical trial enrolled patients with persistent AF and idiopathic cardiomyopathy (left ventricular ejection fraction [LVEF] 45%). The primary end point was DLVEF on repeat cardiac magnetic resonance (CMR) at 6 months. In the 68 patients randomized, the absolute LVEF improved by 18% 6 13% in the CA group compared with 4.4% 6 13% in the MRC group (P , .0001) and normalized (LVEF 50%) in 58% vs 9% (P 5 .0002). In those undergoing CA, the absence of late gadolinium enhancement predicted greater improvements in absolute LVEF (10.7%; P 5 .0069) and normalization at 6 months (73% vs 29%; P 5 .0093). The authors conclude that AF is an underappreciated reversible cause of LVSD in this population despite adequate rate control. The restoration of sinus rhythm with CA results in significant improvements in ventricular function, particularly in the absence of ventricular fibrosis on CMR. Coronary artery disease in patients with out-of-hospital refractory ventricular fibrillation cardiac arrest Yannopoulos et al (J Am Coll Cardiol 2017;70:1109, PMID 28838358) evaluated a novel protocol for refractory out-ofhospital ventricular fibrillation (OOHVF) of early extracorporeal life support (ECLS) and revascularization. Of the 55 patients meeting entry criteria, 5 had return of spontaneous circulation and 50 received ECLS. Forty-six of 55 patients (84%) had significant coronary artery disease (CAD), 35 of 55 (64%) had acute thrombotic lesions, and 46 of 55 (84%) had percutaneous coronary intervention. Twenty-six of 55 (47%) patients were discharged alive with cerebral performance category 1 or 2 vs 26 of 170 (15%) in the historical comparison group (hazard ratio 4.0; P , .0001). The authors conclude that treatable CAD was prevalent in patients with refractory OOHVF cardiac arrest who also met criteria for continuing resuscitation in the cardiac catheterization laboratory. Address reprint requests and correspondence: Dr N.A. Mark Estes III, Tufts Medical Center, 800 Washington St, Boston, MA 02111. E-mail address: [email protected].
1547-5271/$-see front matter
Assessment of remote heart rhythm sampling using the ambulatory monitoring to screen for atrial fibrillation Halcox et al (Circulation 2017;Epub ahead of print, PMID 28851729) conducted a randomized controlled trial of atrial fibrillation (AF) screening using an ambulatory monitor with a smart phone attached to a WiFi-enabled iPod to obtain electrocardiograms (iECGs) in ambulatory patients. Patients 65 years and older with CHADS-VASc score 2 free from AF were randomized to the iECG arm or routine care (RC). Participants in the iECG arm acquired iECGs twice weekly over 12 months. Time to diagnosis of AF was the primary outcome measure. A total of 1001 patients were randomized (500 iECG, 501 RC). Nineteen patients in the iECG arm were diagnosed with AF over the 12-month study period vs 5 in the RC arm (hazard ratio 3.9; P 5 .007) at a cost per AF diagnosis of $10,780. There was a similar number of stroke/transient ischemic attack/systemic embolic events (iECG vs RC: 6 vs 10; hazard ratio 0.61; P 5 .34). The authors conclude that screening with a twice-weekly single-lead iECG in ambulatory patients 65 years and older at an increased risk of stroke is significantly more likely to identify incident AF than is RC over a 12-month period. Dual antithrombotic therapy with dabigatran after PCI in atrial fibrillation Cannon et al (N Engl J Med 2017;Epub ahead of print; PMID 28844193) randomized 2725 patients with atrial fibrillation (AF) with percutaneous coronary intervention (PCI) to triple therapy with warfarin plus a P2Y12 inhibitor (clopidogrel or ticagrelor) and aspirin (for 1–3 months) (triple-therapy group) or to dual therapy with dabigatran (110 or 150 mg twice daily) plus a P2Y12 inhibitor (clopidogrel or ticagrelor) and no aspirin (dual-therapy group). The composite efficacy end point was thromboembolic events, death, or unplanned revascularization. The incidence of the primary end point was 15.4% in the 110-mg dual-therapy group compared with 26.9% in the triple-therapy group (hazard ratio 0.52; P , .001 for noninferiority and P , .001 for superiority) and 20.2% in the 150-mg dual-therapy group compared with 25.7% in the corresponding triple-therapy group. The rate of serious adverse events did not differ significantly among the groups. The authors conclude that among patients with AF who had undergone PCI, the risk of bleeding was lower in those who received dual therapy than in those who received triple therapy and that dual therapy was noninferior to triple therapy with respect to the risk of thromboembolic events. https://doi.org/10.1016/j.hrthm.2017.09.022
Catheter ablation vs medical rate control in atrial fibrillation and systolic dysfunction Prabhu et al (J Am Coll Cardiol 2017;Epub ahead of print; PMID 28855115) evaluated whether catheter ablation (CA) for atrial fibrillation (AF) could improve left ventricular systolic dysfunction (LVSD) compared with medical rate control (MRC) where the etiology of the LVSD was unexplained, apart from the presence of AF. This multicenter randomized clinical trial enrolled patients with persistent AF and idiopathic cardiomyopathy (left ventricular ejection fraction [LVEF] 45%). The primary end point was DLVEF on repeat cardiac magnetic resonance (CMR) at 6 months. In the 68 patients randomized, the absolute LVEF improved by 18% 6 13% in the CA group compared with 4.4% 6 13% in the MRC group (P , .0001) and normalized (LVEF 50%) in 58% vs 9% (P 5 .0002). In those undergoing CA, the absence of late gadolinium enhancement predicted greater improvements in absolute LVEF (10.7%; P 5 .0069) and normalization at 6 months (73% vs 29%; P 5 .0093). The authors conclude that AF is an underappreciated reversible cause of LVSD in this population despite adequate rate control. The restoration of sinus rhythm with CA results in significant improvements in ventricular function, particularly in the absence of ventricular fibrosis on CMR. Coronary artery disease in patients with out-of-hospital refractory ventricular fibrillation cardiac arrest Yannopoulos et al (J Am Coll Cardiol 2017;70:1109, PMID 28838358) evaluated a novel protocol for refractory out-ofhospital ventricular fibrillation (OOHVF) of early extracorporeal life support (ECLS) and revascularization. Of the 55 patients meeting entry criteria, 5 had return of spontaneous circulation and 50 received ECLS. Forty-six of 55 patients (84%) had significant coronary artery disease (CAD), 35 of 55 (64%) had acute thrombotic lesions, and 46 of 55 (84%) had percutaneous coronary intervention. Twenty-six of 55 (47%) patients were discharged alive with cerebral performance category 1 or 2 vs 26 of 170 (15%) in the historical comparison group (hazard ratio 4.0; P , .0001). The authors conclude that treatable CAD was prevalent in patients with refractory OOHVF cardiac arrest who also met criteria for continuing resuscitation in the cardiac catheterization laboratory. Address reprint requests and correspondence: Dr N.A. Mark Estes III, Tufts Medical Center, 800 Washington St, Boston, MA 02111. E-mail address: [email protected].
1547-5271/$-see front matter
Assessment of remote heart rhythm sampling using the ambulatory monitoring to screen for atrial fibrillation Halcox et al (Circulation 2017;Epub ahead of print, PMID 28851729) conducted a randomized controlled trial of atrial fibrillation (AF) screening using an ambulatory monitor with a smart phone attached to a WiFi-enabled iPod to obtain electrocardiograms (iECGs) in ambulatory patients. Patients 65 years and older with CHADS-VASc score 2 free from AF were randomized to the iECG arm or routine care (RC). Participants in the iECG arm acquired iECGs twice weekly over 12 months. Time to diagnosis of AF was the primary outcome measure. A total of 1001 patients were randomized (500 iECG, 501 RC). Nineteen patients in the iECG arm were diagnosed with AF over the 12-month study period vs 5 in the RC arm (hazard ratio 3.9; P 5 .007) at a cost per AF diagnosis of $10,780. There was a similar number of stroke/transient ischemic attack/systemic embolic events (iECG vs RC: 6 vs 10; hazard ratio 0.61; P 5 .34). The authors conclude that screening with a twice-weekly single-lead iECG in ambulatory patients 65 years and older at an increased risk of stroke is significantly more likely to identify incident AF than is RC over a 12-month period. Dual antithrombotic therapy with dabigatran after PCI in atrial fibrillation Cannon et al (N Engl J Med 2017;Epub ahead of print; PMID 28844193) randomized 2725 patients with atrial fibrillation (AF) with percutaneous coronary intervention (PCI) to triple therapy with warfarin plus a P2Y12 inhibitor (clopidogrel or ticagrelor) and aspirin (for 1–3 months) (triple-therapy group) or to dual therapy with dabigatran (110 or 150 mg twice daily) plus a P2Y12 inhibitor (clopidogrel or ticagrelor) and no aspirin (dual-therapy group). The composite efficacy end point was thromboembolic events, death, or unplanned revascularization. The incidence of the primary end point was 15.4% in the 110-mg dual-therapy group compared with 26.9% in the triple-therapy group (hazard ratio 0.52; P , .001 for noninferiority and P , .001 for superiority) and 20.2% in the 150-mg dual-therapy group compared with 25.7% in the corresponding triple-therapy group. The rate of serious adverse events did not differ significantly among the groups. The authors conclude that among patients with AF who had undergone PCI, the risk of bleeding was lower in those who received dual therapy than in those who received triple therapy and that dual therapy was noninferior to triple therapy with respect to the risk of thromboembolic events. https://doi.org/10.1016/j.hrthm.2017.09.022