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Please review the following seven cases and answer the questions. You may use the Next/Prev buttons to navigate the cases. For each case, relevant action buttons are shown on the left of the main screen.
Pressing the Pause button stops the screen. When paused, a caliper in activated by pressing the left mouse button and dragging the mouse cursor to the desired location while holding the mouse button down. Restart sweeping by pressing Resume.
Case #1: Deliver an atrial extrastimulus at a train cycle length (S1) of 600 ms and a coupling interval (S2) starting at 400 ms down to 300 ms. What is AVERP? Can you describe what you see and its significance?
Case #2: Try ventricular entrainment during this narrow complex regular tachycardia. Describe the return pattern (VAV vs VAAV). How long is the post-pacing interval (PPI)? What is the mechanism of tachycardia?
Hint: If tachycardia terminates during ventricular pacing, you can reinitiate it by pressing Induce.
Case #3: This case is similar to Case #2. Try ventricular entrainment. Describe the return pattern (VAV vs VAAV). How long is the post-pacing interval (PPI)? What is the mechanism of tachycardia?
Hint:If the tachycardia breaks during ventricular pacing, you can reinitiate it by pressing Induce.
Case #4: Another case similar to Case #2. This time, try atrial entrainment. Describe the return pattern (AHA vs AHHA). What is the mechanism of tachycardia?
Case #5: Try tachycardia induction by delivering an atrial extrastimulus at a train cycle length (S1) of 600 ms and a coupling interval (S2) starting at 400 ms and down. Pay attention to the QRS morphology during sinus rhythm and tachycardia. What is the mechanism of tachycardia?
Case #6: This is a case of wide-complex regular tachycardia. The ablation catheter is placed in distal coronary sinus. Turn on ablation (by pressing the Ablation On button) until a change occurs. Describe the mechanism of the observed changes in the QRS morphology and intracardiac activation.
Hint: To replay tachycardia, move back to the previous page and then return.
Case #7: Now, we practice how to measure ΔHA. First, measure HASVT during tachycardia (remember to Pause!). HA is measured from His potential to HRA. Next, cardiovert and pace the ventricles in sinus rhythm at the same cycle length as in the tachycardia. Measure HApaced.
ΔHA is defined as HApaced - HASVT. A positive value suggests AVNRT and a negative value ORT.
is a web-based cardiac electrophysiology study (EPS)/arrhythmia simulator, which
is primarily designed for training and education. Its target audience includes
cardiology and clinical cardiac electrophysiology fellows-in-training and electrophysiology
laboratory nurses and technicians. svtsim provides
an environment to simulate different cardiac arrhythmias.
It allows the user to perform various diagnostic maneuvers by pacing the simulated heart in realtime.