Case 21: Postero-septal Accessory Pathway in a 10-Year-Old Girl

A 10-year-old girl was detected with a delta wave and a short PR on the surface ECG. The appearance was that of a left postero-septal accessory pathway with a positive delta wave in V1 and negative in D2, D3, and avF. She came to the outpatient clinic for the noninvasive evaluation of the risk associated with the accessory pathway. During the treadmill exercise test, she achieved a maximum heart rate of 190 beats per minute. The delta wave disappeared slowly at a rate of 100 beats per minute, making it difficult to accurately assess the refractory period of the accessory pathway and the risk for fatal arrhythmias (Fig. 27.1, 27.2, 27.3, 27.4, 27.5, 27.6, 27.7, 27.8, 27.9, 27.10, 27.11, 27.12, 27.13, 27.14, 27.15, 27.16, 27.17, 27.18, 27.19, 27.20, 27.21, 27.22, 27.23, 27.24, 27.25, 27.26, 27.27, 27.28, 27.29, 27.30, and 27.31).