Abstract 11297: Usefulness of Low Intensity Exercise Stress Echocardiography for Predicting Exercise Tolerance in Patients with Atrial Fibrillation

Abstract

Background: Exercise stress echocardiography is well recognized to reflect exercise capacity in patients with sinus rhythm. The incidence of atrial fibrillation (AF) is higher in elder people. However, usefulness of exercise stress echocardiography for predicting exercise tolerance in patients with AF is unknown, especially with such low intensity load as to be feasible even with elder people.

Methods: Fifty patients (age: 60±12 years, 16 females) with AF and preserved LVEF were studied using 2-dimensional speckle tracking echocardiography at rest and during low intensity exercise by supine bicycle (20W, 10min). We measured systolic rotation (Rot) and peak rotation rate in systolic, early diastolic and atrial contractile phase (sRotR, eRotR, and aRotR) for 5 consecutive beats in apical and basal level of left ventricle. All patients underwent cardiopulmonary exercise testing to obtain the peak oxygen consumption (PeakVO2).

Results: AF patients were divided into 2 groups: 21 patients with persistent AF (group A) and 29 patients with paroxysmal AF (group B). PeakVO2 in group A was lower than that in group B (19.3 ± 5.6 vs 24.6 ± 8.8 ml/min/kg, p<0.05). In group A, apical and basal Rot at rest, and the increments (Δ) of sRotR and eRotR during low intensity exercise were significantly correlated to peakVO2. In group B, apical ΔsRotR and ΔaRotR had significant correlations with peakVO2 (table). Multivariable stepwise regression analysis showed that apical ΔRot and basal Rot at rest in group A and apical ΔaRotR in group B were independently associated with PeakVO2 (table). Using a receiver-operating-characteristic analysis, the area under the curve to predict peakVO2 of < 21ml/kg/min were 0.90 for apical ΔRot in group A and 0.75 for apical ΔaRotR in group B, respectively.

Conclusions: Low intensity exercise stress echocardiography may have potential to predict exercise capacity in patients with persistent or paroxysmal AF.