The impact of ECG synchronization during acquisition of left‑atrium computed tomography model on radiation dose and arrhythmia recurrence rate after catheter ablation of atrial fibrillation - a prospective, randomized study

BACKGROUND

The impact of ECG gating during computed tomography (CT) acquisition of left atrium (LA) model on radiation dose, image quality and ablation event-free survival rate after catheter ablation (CA) of atrial fibrillation (AF) is not well defined.

METHODS

Sixty-two patients with paroxysmal atrial fibrillation were randomized for two types of LA CT (with vs without ECG gating) before CA. Pulmonary veins isolation was performed in all patients. Patients were followed for 12 months after CA.

RESULTS

There was no difference between the groups in CA length (131.61±32.57 vs 119.84±33.18 min; p=0.108), CA fluoroscopy time (4.48±2.19 vs 3.89±1.83 min; p=0.251), CA fluoroscopy dose (3.99±2.79 vs 3.91 vs2.91 Gy*cm2; p=0.735), visual data quality (1.77±0.88 vs 2.0±0.63; p=0.102) and registration error (2.42±0.72 vs 2.43±0.46 mm; p=0.612). We found a significant difference in CT Dose index (89.55±5.99 vs 19.19±4.33 mGy; p<0.0001) and Dose Length product (1438.87±147.75 vs 328.21±73.83 mGy*cm; p<0.0001). Twelve months after CA, 25 of 31 patients in the gated group and 24 of 31 patients in the non-gated group were free of AF (80.65 vs 77.42 %; p=0.838).

CONCLUSION

ECG gating of computed tomography of LA before AF ablation burdens patients with a four times higher radiation dose while improving neither the quality of CT model or fusion of CT with the electroanatomic map. As a result, it has no significant impact on arrhythmia recurrence rate after ablation (Tab. 3, Fig. 3, Ref. 25).

ECG non-gated multi-detector computed tomography protocol prior to catheter ablation of atrial fibrillation provides sufficient data quality with lower radiation exposure compared to ECG-gated protocol - results of a prospective, randomized and blinded study

BACKGROUND

The role of ECG-gating in left atrium (LA) computed tomography (MDCT) imaging is not precisely defined.

METHODS AND RESULTS

62 patients were randomized according to ECG gating with prospective evaluation of image quality, Volume CT Dose Index, Dose Length Product, Effective Dose and registration error between anatomical map and MDCT. We found significant difference in all radiation variables, but not in visual quality, registration error, CA duration, CA fluoroscopy time and CA fluoroscopy dose.

CONCLUSION

Helical non-gated MDCT achieved a radiation dose more than four times lower with comparable image quality and course of ablation compared to ECG-gated protocol.