Nonexercise stress transthoracic echocardiography: Transesophageal atrial pacing versus dobutamine stress

OBJECTIVES To compare transesophageal atrial pacing stress echocardiography with dobutamine stress echocardiography for feasibility, safety, duration, patient acceptance and concordance in inducing wall motion abnormalities. BACKGROUND Transesophageal atrial pacing is an effective method of increasi ng heart rate and has been used in the assessment of coronary artery diseas e. METHODS Both tests were performed in sequence on the same patients in rando m order. Transesophageal atrial pacing stress echocardiography began at a h eart rate of 10 beats/min above the baseline value and was increased by 20 beats/min every two min until 85% of the age-predicted maximum heart rate o r another end point was reached. Dobutamine echocardiography was performed using three-min stages and a maximum dose of 40 mu g/kg per min. Atropine ( total dose less than or equal to 2 mg) was administered at the start of the 40 mu g/kg per min stage if needed to augment heart rate or during pacing if Wenckebach heart block occurred. RESULTS Transesophageal atrial pacing stress echocardiography was feasible in 100 of 104 patients (96%); the duration (8.6 +/- 3.6 min) was significan tly shorter than that of dobutamine stress echocardiography (15.1 +/- 3.9 m in) (p = 0.0001). With transesophageal atrial pacing stress echocardiograph y, the recovery period was shorter, symptoms and dysrhythmias were fewer, h ypertension and hypotension were less common and target heart Tate was more frequently achieved. No complications occurred with either test. Patient a cceptance was satisfactory. Agreement between results of both tests was goo d for segmental wall motion scoring with a 16-segment model, scores 1 to 5 (kappa: rest, 0.79; peak, 0.57) and test interpretation (normal, ischemia, infarction or resting wall motion abnormality with ischemia) (kappa: 0.77). CONCLUSIONS Transesophageal atrial pacing stress echocardiography is a feas ible, well-tolerated alternative to dobutamine stress echocardiography. It can be performed rapidly and shows good agreement with dobutamine stress ec hocardiography in the induction of myocardial ischemia. (C) 1999 by the Ame rican College of Cardiology.