A vectorcardiographic study of WPW syndrome.

Abstract

(1) A vectorcardiographic analysis was made in 30 subjects of WPW syndrome, in correlation to the electrocardiographic classification of Ueda's criteria.(2) In type A (14 cases) whose QRS complex in V1 is characterized by R or Rs pattern, the initial QRS vector was directed superiorly or inferiorly, followed by the main body of QRS loop oriented anteriorly or left-anteriorly, and T loop was situated slightly posteriorly to QRS loop with narrow QRS-T angle.(3) Type B (8 cases) showing rS pattern in V1, had many vectorcardiographic values similar to type C, but had a definite forward deflection in its initial vector with the following QRS loop showing a wide range of leftward direction with variable QRS-T angle.(4) In type C (8 cases) that has QS or W pattern in V1, it was shownthat the initial QRS vector and the following QRS loop were directed straight to the left, slightly anteriorly or posteriorly with wide QRS-T angle.(5) Investigations were also made on the polar vector of QRS and T loops, which was found to occupy the spatial octant characteristic of the foregoing respective type. The polar vector of T loop of WPW syndrome was suggested to have some resemblance to that of bundle branch clock.