Atrial Fibrillation Detection in ESUS patients
All 307 patients with ESUS were given a prescription for CEM. Out of the 307 patients, 155 completed the monitoring process successfully. The rest either declined or were unable to complete the process. Of the 155 patients who completed monitoring, 88 only had a 30-day CEM and 67 also had successful ILR in addition to the CEM, while the rest either declined or were lost to follow-up. Among all 307 ESUS patients, AF was detected in 32 patients who received scheduled cardiac monitoring. Additionally, 7 patients who did not receive scheduled cardiac monitoring were incidentally found to have AF in subsequent outpatient or hospital visits. Patients with AF detected had significantly decreased mean LA reservoir strain (25.15±13.57 vs. 32.95±16.20, p = 0.005), LA contractile strain (12.24±10.00 vs. 15.95±9.41, p = 0.023), and LA conduit strain (12.91±6.45 vs. 17.00±11.09, p = 0.025) compared to patients without AF detected (Table 3). In the sensitivity analysis using the 32 ESUS patients found to have AF on cardiac monitoring, there was no significant difference in LA reservoir strain (26.15+ 15.25 vs. 26.50+ 12.17, p = 0.953), LA contractile strain (12.79+ 11.90 vs. 11.56+ 6.74, p = 0.785), and LA conduit strain (13.36 + 6.31 vs. 14.94+ 7.12, p = 0.557) between those with an AF burden of less than 24 hours compared to those with an AF burden of greater than or equal to 24 hours likely due to small sample size (Table 4). In the sensitivity analysis using only the 155 ESUS patients who received cardiac monitoring, the effect size of LA strain remained stable, but significance was also lost likely due to small sample size (Supplementary Table 1).