ntracardiac Electrogram Questions
The following questions deal with intracardiac electrograms. Select the question from the table at the left and review the question and the recorded electrogram(s) associated with the question. When you feel you have answered the question correctly, click on answer to see my own interpretation of the information provided.
Question 1 |
A 52 year old female patient with a history of atrial fibrillation refractory to treatment via medications is referred for complete ablation of the AV Node and permanent pacemaker implant. The procedure is successful with complete loss of AV conduction documented at 14 seconds into the second burn. Total ablation time is 47 seconds. A dual chamber, rate responsive pacemaker with autocapture is implanted after the ablation. During the implant, the ventricular lead was positioned a total of three times due to elevated capture thresholds. Final ventricular implant measurements are as follows: R wave = 12.4mv, threshold = 0.9v at 0.50ms, current = 1.1ma, lead resistance = 877ohms, slew rate = 1.9v/s. The pacemaker was set at 60ppm in DDD mode with activity sensor in passive mode. Autocapture is programmed on after initial testing showed acceptable results. The patient was atrial tracking at 64bpm when she was returned to the Telemetry Ward. Approximately three hours after the procedure is completed, you are notified that the patient has had two runs of ventricular tachycardia that lasted 12 and 17 seconds. The physician is most likely to order which of the following..... A) Return the patient to the EP Lab for emergency VT Study. |
