To study the characteristics of the ventriculoatrial conduction system in palienfs capable of rapid antegrade atrioventricuiar conduction, eiectrophysiologic studies were performed in 23 subjects capable of 1:1 atrioventricular conduction at atrial cycle lengths < 300 ms (Group I). and in 23 subjects with normal 1:1 atrioventricular conduction (Group II). During venfricular pacing, ventriculoatrial block at all cycle lengths was seen in 5/23 (22%) in Group I and in 7/23 (30%) in Group II patients (p = NS). In the remainder, the minimum ventricuar pacing cycle length maintaining 1:1 ventriculoatrial conduction was 359 ± 85 ms in Group I, compared to 444 ± 118 ms in Group II (p < .02). Both flat and exponential VA conduction interval curves, drawn as a function of pacing cycle length, were observed in both groups. Discontinuous ventricuioatrial conduction curves were seen in 5/18 (28%) Group I and 1/16 (6%) Group II patients (p = NS). In conclusion, retrograde ventriculoatrial conduction, when present in patients capable of rapid 1:1 atrioventricular conduction, is maintained at shorter cycle lengths than in patients with normal atrioventricular conduction. Quantitative, rather than qualitative, differences distinguish the two groups.
|Original language||English (US)|
|Number of pages||9|
|Journal||Pacing and Clinical Electrophysiology|
|State||Published - Jan 1987|
All Science Journal Classification (ASJC) codes
- Cardiology and Cardiovascular Medicine