CT-Guided Direct Current Cardioversion for Atrial Arrhythmias During the COVID-19 Pandemic

Objective

To assess left atrial appendage (LAA) thrombus detection using a novel cardiac computed tomography (CT) protocol specifically prior to direct current cardioversion (DCCV).

Background

Transesophageal echocardiography (TEE) is the gold standard in evaluating the LAA prior to DCCV for atrial fibrillation (AF) or flutter (AFL). The COVID-19 pandemic has restricted availability of TEE and anesthesia support.

Methods

Prospective cohort of consecutive patients with uncontrolled AF/AFL referred for DCCV from March 2020 to March 2021 were enrolled. CT evaluation of LAA was performed with an initial arterial and subsequent 30-second delayed acquisition to exclude thrombus prior to DCCV. Primary end points were to assess safety and outcomes.

Results

A total of 161 patients were included; mean age 69.8 ± 11.1 years; mean CHA₂DS₂-VASc 3.4 ± 1.7; and HAS-BLED 1.8 ± 0.9. Median follow-up 175 (105-267) days with zero cardiac-related deaths, and no episodes of TIA or embolic stroke. There was no statistically significant change in mean glomerular filtration rate (GFR) in the study population between the pre- and post-GFR measurements (73.9 ± 21.0 vs 72.7 ± 20.3; p=0.104). Overall mean total dose length product (DLP) was 1042.8 ± 447.5 mGy*cm. Modifying the CT protocol to a narrower 8-cm axial coverage had a statistically significant decrease in total DLP (from 1130.6 ± 464.1 mGy*cm to 802.1 ± 286.4 mGy*cm; P<0.0001).

Conclusion

Cardiac CT is both a safe and feasible alternative imaging to TEE for patients prior to DCCV.

Perspectives