Quinidine Cardioversion

Report:

Atrial flutter with variable block

Spontaneous termination

Sinus rhythm

Sinus bradycardia (top strip)

Sinus pauses (middle strip)

Normal sinus rhythm (bottom strip)

Left atrial abnormality (LAA)

Right bundle branch block

Comment:

The symptomatic patients with sick sinus (tachycardia-bradycardia) syndrome often experience symptoms at the time of the termination of tachycardia, due to the slowness of the sinus escape. This patient remained asleep throughout.[!xe "Tachycardia-bradycardia syndrome" \t "See Sick sinus syndrome"!]

"Sinus pauses" is an imprecise but convenient term, used because it is not possible to decide upon the mechanism of the pauses: exit block or arrest.

Quinidine/digoxin regimen used to be standard therapy for atrial fibrillation and flutter: the patient was digitalised, then started (after a test dose) on quinidine, then digoxin would be stopped and DC cardioversion scheduled in 48 hours. Many patients would revert to sinus rhythm, like this one, before the countershock.

Anticoagulation before and after cardioversion remains, especially for AF, an important part of the protocol.

The nurses aide-mémoire at the bottom is retained, if only to remind the reader not to deface the original tracings with commentary. It may preclude publication or its use in examinations. This one could of course have been simply excised.