"Supernormal Conduction" of a Premature Impulse
نویسندگان
چکیده
Electrophysiological studies with atrial extrastimulus technique suggested the presence of dual atrioventricular (A-V) nodal pathways in a patient with hypothyroidism, as evidenced by a sudden increase of H,-H2 intervals at critical A,-A2 coupling intervals. Following the atrial extrastimulus (A2), a third impulse (A3) occurred spontaneously. During slow pathway conduction of A2, an A3, appearing at a critically timed interval allowed fast pathway conduction, resulting in an earlier than expected QRS ( a form of supernormal conduction). This demonstration of fast pathway conduction during slow pathway conduction adds strong evidence for the existence of dual A-V nodal pathways.
منابع مشابه
"Supernormal conduction" of a premature impulse utilizing the fast pathway in a patient with dual atrioventricular nodal pathways.
Electrophysiological studies with atrial extrastimulus technique suggested the presence of dual atrioventricular (A-V) nodal pathways in a patient with hypothyroidism, as evidenced by a sudden increase of H1-H2 intervals at critical A1-A2 coupling intervals. Following the atrial extrastimulus (A2), a third impulse (A3) occurred spontaneously. During slow pathway conduction of A2, and A3, appear...
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