Aspect on Poincare diagram supports the hypothesis of
    atrioventricular re-entry during atrial fibrillation

Corlan Alexandru Dan; Bălănescu Serban; Cinteză Mircea; Vasilescu Ileana; Dorobantu Maria; Vinereanu Dragos; Dimulescu Doina; Gherasim
    Leonida

Aspect on Poincare diagram supports the hypothesis of atrioventricular re-entry during atrial fibrillation

Corlan Alexandru Dan, Bălănescu Serban, Cinteză Mircea, Vasilescu Ileana, Dorobantu Maria, Vinereanu Dragos, Dimulescu Doina, Gherasim Leonida,

Eur Heart J 16 (suppl):275-275, 1995

ABSTRACT

BACKGROUND: 1. In patients having both a slow and a fast AV node pathway, with different refractory periods, an impulse from atria leads to a reciprocal beat if it comes in the refractory period of the slow pathway. This condition should be far more common during atrial fibrillation (AF) than after a SV premature beat. 2. Poincare diagrams of ventricular rhythm are graphics in which every pair of R-R intervals is represented by a plot, with x corresponding to an interval and y to the next. AF with unimodal RR distribution appears as a single group of points (type A). AF with both short (S) and long (L) cycles has either type B (L-L, L-S and S-L pairs), type C (L-L, L-S, S-L, S-S) or type D (S-S, S-L, L-S). Each kind of pair appears as a group of points.

PURPOSE: We assessed the statistical properties of groups of points in order to detect their potentially different pathogenic mechanisms.

METHODS: We performed 174 rest one hour single lead ECG recordings in 97 patients with AF of various etiology. We developed a computer program which calculated the correlation coefficient (r), the ovality of every group of points and other parameters. Ovality (ov) was defined as the ratio between the dispersion on the group on the first (45 °) axis and on the second (135 °) axis. Higher ovality as well as higher correlation coefficient reflect closer dependence between one RR cycle and the next. RESULTS: In types B, C and D the correlation coefficient of S-S pairs is significantly higher (p<0.000001) than that of L-L pairs, and is also significantly higher (p;0.0001) than that of the single group in the A type. Same is true about ovality (p<0.000001 and respectivelly p<0.001).

Type	N	param	L-L	L-S	S-L	S-S
A	105	r	0.11 ±0.09	-	-	-
		ov	1.11 ±0.12	-	-	-
B	34	r	0.04 ±0.07	0.12 ±0.09	0.06 ±0.17	-
		ov	1.02 ±0.10	1.11 ±0.09	1.00 ±0.0	-
C	26	r	0.04 ±0.09	0.13 ±0.09	0.02 ±0.05	0.21 ±0.11
		ov	1.00 ±0.07	1.11 ±0.1	0.96 ±0.06	1.20 ±0.14
D	9	r	-	0.07 ±0.09	0.08 ±0.17	0.19 ±0.12
		ov	-	1.02 ±0.13	1.03 ±0.25	1.20 ±0.17

CONCLUSION: The higher correlation between S-S cycle sequences is compatible with the hypothesis that the short cycles are given by reentry in the AV node, with one part of the reentry circuit through the atrial myocardium, because most of the circuit parameter would change little from one cycle to the next. The long cycles may be given by a less predictable mechanism, such as concealed conduction.