What kind of device does this patient have?
This ECG shows atrial fibrillation with ventricular only pacing. V1 demonstrates dominant R wave and lead I and aVL starts with a q wave. Frontal plane QRS axis is left superior which is consistent with a CRT device. BiV pacing from lateral coronary venous branches and right ventricular apex characteristically presented with dominant R wave in V1, q or Q wave in leads I and aVL, and right or left superior axis.