Transient local changes in right ventricular monophasic action potentials due to ajmaline in a patient with Brugada Syndrome.
A 48-year-old patient with recurrent episodes of palpitations and syncope presented with transient ST segment elevation in the right precordial ECG leads. Structural heart disease was excluded. No arrhythmias were inducible by programmed ventricular stimulation. Parallel to ST elevation after intravenous ajmaline, a gradual and reversible delay in the upstroke of right ventricular (RV) monophasic action potentials (MAPs) occurred that was most marked in the RV outflow tract and nearly absent at right free-wall recordings. Ajmaline led to a cycle length-dependent increase in RV dispersion of repolarization. Thus, right endocardial MAPs may demonstrate regionally different action potential changes that may contribute to the ECG changes in Brugada syndrome.
Hospital of the Westfälische WilheLms-University, Department of Cardiology and Angiology and Institute for Arteriosclerosis Research, Münster, Germany. l.eckardt@uni-muenster.de
L
L
Eckardt
P
P
Kirchhof
R
R
Johna
G
G
Breithardt
M
M
Borggrefe
W
W
Haverkamp
D000200:Action Potentials / Q000502:physiology*; D000404:Ajmaline / Q000008:administration & dosage*; D000889:Anti-Arrhythmia Agents / Q000008:administration & dosage*; D017147:Defibrillators, Implantable; D004562:Electrocardiography; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007275:Injections, Intravenous; D008875:Middle Aged; D013577:Syndrome; D017180:Tachycardia, Ventricular / Q000188:drug therapy / Q000503:physiopathology; D014693:Ventricular Fibrillation / Q000503:physiopathology* / Q000517:prevention & control; D016278:Ventricular Function, Right / Q000187:drug effects*
D000889:Anti-Arrhythmia Agents; D000404:Ajmaline