Isolated diastolic potentials as predictors of success in ablation of right ventricular outflow tract idiopathic premature ventricular contractions

Figures

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  Fig 1. Diastolic potentials. Representative intracardiac electrograms at a successful ablation sites of 3 different patients. The MAPd exhibits the diastolic potentials (arrow head), occurring after the T wave of the surface ECG in sinus rhythm, becoming pre-QRS during the PVCs. The gain in the ablation catheter is 20 mm/1mV and sweep speed is 100 mm/sec. (A), fragmented diastolic potential preceding the QRS by -100 ms; (B) sharp diastolic potential preceding the QRS by—60 ms. (C) dull diastolic potential preceding the QRS by -20 ms. In panel B and C the local electrogram in sinus rhythm displays normal amplitude and duration. In Panel A the local electrogram shows low voltage and prolonged duration.

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  Fig 2. Fragmented electrograms. Intracardiac electrograms at successful ablation site. The bipolar electrogram on the ablation catheter (MAPd) exhibits a typical fragmented electrogram, diastolic potentials are also present (arrow heads). The fragmented electrogram shows low voltage and prolonged duration, 220 ms, but ending before the end of the QRS.

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  Fig 3. Variation in the inter diastolic potentials interval leading to a variation in the inter PVC interval. Intracardiac electrogram at successful ablation site. The bipolar electrogram on the ablation catheter (MAPd) exhibits sharp diastolic potentials (arrow head) after the T wave of the surface ECG in sinus rhythm, becoming pre-QRS during the PVCs. The variation of the interval between consecutive diastolic potentials is accompanied by a variation in the interval between the consecutive PVCs.

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  Fig 4. Low voltage areas. 35 years old female (patient 48) showing abnormal electrograms at ablation site despite apparent absence of structural heart disease. (A) Cardiac magnetic resonance steady-state free-procession (SSFP) cine imaging in the in-out view of the right ventricle in diastole (A1) and systole (A2) showing no abnormalities. (B) Electroanatomical voltage map in sinus rhythm. The black line indicates the pulmonary valve. The voltage map showing a wide area of low voltage below the pulmonary valve. The color map of voltage signals is explained in the methods. Purple indicates normal tissue while red indicates scar. Decapolar catheter in the coronary sinus and the His bundle catheter are displayed in white and red, respectively, at the bottom of the figure. The ablation catheter at the ablation site is indicated by the white arrow head. One RF ablation at this site caused the disappearance of the PVCs, indicated by the red dots. (C) The bipolar electrogram on the ablation catheter (MAPd) at successful ablation site exhibits very low voltage electrograms and dull diastolic potentials (black arrow heads) in sinus rhythm preceding the QRS by -20 ms during the PVC.