HRCR April 2020 Quiz

Editorial note: The following quiz is related to the article Single ring isolation for atrial fibrillation ablation: How to do it and avoid the esophagus by Mahajan and colleagues from the April 2020 issue of Heart Rhythm Case Reports.

Question 1: Which of the following statements is true?

A. The thickness of the left atrial wall is similar throughout with very little variation.
B. The part of the anterior wall immediately adjacent to the left atrial appendage can be very thin (1-2mm) and is a common site for left atrial diverticulum.
C. The posterior wall of the left atrium is a complex structure with thickness of 2mm at the pulmonary vein junction that gradually decreases to 1.5mm towards the center of the posterior wall.
D. There is absence of a distinctive pattern of arrangement of myocardial fibers in the posterior left atrium and hence the propensity for atrial fibrillation.

Question 2: Which of the following is false regarding single ring isolation approach for pulmonary vein isolation?

A. The rationale for single ring isolation is to combine the advantages of isolating the posterior wall en bloc with the pulmonary vein without increase in delivery of radiofrequency energy on the posterior wall.
B. Single ring isolation is achievable in all cases without additional ablation within the ring.
C. Single ring isolation may be achieved in some patients with minimal ablation on the posterior wall.
D. Single ring isolation results in greater ablation on the posterior wall.

Question 3: In order to minimize ablation on posterior wall during single ring isolation and reduce the likelihood of additional lesions within ring to achieve electrical isolation:

A. Inferior line should be performed first.
B. Roof line should be as anterior as possible to include more atrial tissue.
C. The roof line should be anterior to a left atrial diverticulum that is located anteriorly and adjacent to right superior pulmonary vein.
D. None of the above.