Coupling Interval Variability of Outflow Tract Premature Ventricular Contractions: A Poincaré Plot‐Based Assessment
Mátyás Jenő Iszlai, Mihai Octavian Negrea, Gelu Simu, Mihai Puiu, Radu Roșu, Dana Pop, Gabriel CismaruABSTRACT
Purpose
Coupling interval variability (ΔCI) of premature ventricular contractions (PVCs) may provide insight into their site of origin. This study evaluated whether ΔCI, quantified by Poincaré graph analysis, can distinguish PVCs arising from the right ventricular outflow tract (RVOT) compared to other locations.
Methods
We screened 117 patients undergoing electroanatomical mapping and catheter ablation for PVCs. Exclusion criteria included: failed ablation, low PVC burden on Holter ECG, non‐sinus baseline rhythm, or absence of a qualifying Holter recording. Sixty patients met these criteria: 34 with RVOT PVCs, 11 with left ventricular outflow tract (LVOT) PVCs, and 15 with non‐RVOT PVCs. ΔCI was assessed using Poincaré plots derived from the Holter ECG recordings.
Results
A ΔCI < 100 ms predicted RVOT origin with a specificity of 100% and a sensitivity of 25%. Poincaré plots effectively visualized CI variability, with narrow PVC clusters (measured along the x ‐axis) corresponding to RVOT origin. Broader clusters were observed in LVOT and other non‐RVOT PVCs, reflecting greater variability.
Conclusions
ΔCI, represented by Poincaré plots, is a reliable and time‐efficient marker of RVOT PVC origin. Narrow PVC clusters with low ΔCI strongly suggest RVOT localization, offering a practical adjunct to vectographic mapping in clinical ablation strategies.