SINUS NODE DECELERATION DURING DOBUTAMINE PERFUSION SCINTIGRAPHY AS A MARKER OF INFERIOR ISCHEMIA

Traditional electrocardiographic markers of exerciseinduced ischemia include ST-segment depression or elevation, U-wave inversion, ventricular ectopy, and chronotropic incompetence. Miller et al1 recently described sinus node deceleration, defined as an initial increase and subsequent decrease in heart rate with progressive exercise, as a marker of atherosclerotic narrowing of the right coronary artery. For patients unable to perform treadmill exercise, dobutamine thallium imaging has emerged as an alternative stress method for the detection of coronary artery disease.2,3 The purpose of this study was to determine if sinus node deceleration occurs during dobutamine perfusion scintigraphy and whether it is a marker of inferior wall ischemia. © 1994.