IBHRE Ablation Procedures and Techniques 1 — Questions and Answers
Question 1: What primary energy source is used in radiofrequency catheter ablation?
- Cryoenergy
- Laser energy
- Radiofrequency alternating electrical current (Correct answer)
- High-intensity ultrasound
Correct answer: Radiofrequency alternating electrical current
Radiofrequency ablation uses alternating electrical current at approximately 500 kHz that generates resistive heating to create coagulative necrosis.
Question 2: What catheter tip temperature range is typically targeted during radiofrequency ablation?
- 25–35°C
- 45–55°C
- 55–70°C (Correct answer)
- 75–85°C
Correct answer: 55–70°C
RF ablation targets catheter tip temperatures of 55–70°C to achieve effective tissue destruction while avoiding char formation and impedance rises.
Question 3: What key safety advantage does cryoablation offer compared to radiofrequency ablation?
- It uses higher temperatures for faster lesions
- It cannot create permanent lesions
- Reversible freezing allows testing before permanent ablation (Correct answer)
- It requires less fluoroscopy
Correct answer: Reversible freezing allows testing before permanent ablation
Cryomapping at around -30°C produces reversible ice injury, allowing assessment of effects such as AV block before committing to permanent cryoablation at -70°C.
Question 4: Pulmonary vein isolation is the cornerstone ablation strategy for which arrhythmia?
- Ventricular tachycardia
- Atrial fibrillation (Correct answer)
- AVNRT
- Typical atrial flutter
Correct answer: Atrial fibrillation
Pulmonary vein isolation electrically disconnects the pulmonary veins from the left atrium, eliminating the primary triggers of atrial fibrillation originating from these structures.
Question 5: Where is the 'slow pathway' targeted during catheter ablation of AVNRT?
- His bundle region
- Posteroseptal region near the coronary sinus os (Correct answer)
- Anteroseptal tricuspid annulus
- Right superior pulmonary vein
Correct answer: Posteroseptal region near the coronary sinus os
The slow AV nodal pathway is located in the posteroseptal region between the tricuspid annulus and coronary sinus os, corresponding to the inferior nodal extension.
Question 6: Catheter ablation of typical right atrial flutter creates a lesion line across which structure?
- Left atrial posterior wall
- Cavo-tricuspid isthmus (Correct answer)
- His bundle region
- Superior vena cava-right atrium junction
Correct answer: Cavo-tricuspid isthmus
The cavo-tricuspid isthmus (CTI) is the critical slow conduction zone for typical flutter, and linear ablation across it terminates and prevents recurrence.
IBHRE Ablation Procedures and Techniques 1
What primary energy source is used in radiofrequency catheter ablation?