She returns for a follow-up visit for palpitations, and a 12-lead ECG is obtained ... negative in leads I and aVF and positive in leads aVR and V1 (^). A second atrial waveform is superimposed ...

The axis of the ECG is the major direction of the overall ... The negative of lead aVR (R for right arm) is at +30 degrees; the positive of lead aVR is actually at -150 degrees.

The Duke Treadmill Score (DTS) is a point system to predict 5-year mortality based on treadmill ECG stress testing in ... in any lead except lead aVR. The angina index gives 0 points if no angina ...

Figure 2: An ECG obtained from a beagle dog 21 days later, showing six rhythm strips simultaneously (leads I, II, III, aVR, aVL and aVF). VPCs are the most frequent type of abnormal rhythm in dogs ...