ABC | Volume 112, Nº5, May 2019

Original Article Correia et al LA stiffness and AF recurrence - a meta-analysis Arq Bras Cardiol. 2019; 112(5):501-508 Table 1 – Characteristics of the included studies Study, year Region Study design Number of Patients Ablation strategy Measurement of LA stiffness Method of AF detection Follow-up, months Blanking period, months Findings Quality Machino Ohtsuka et al., 2011 Asia Prospective case series, single centre 155 PVI Ratio of the difference between the LA peak v-wave pressure and the LA x-wave pressure nadir of the global S-LAs [(LAP-v – LAP-x) / global S-LAs] 12-lead ECG, arrhythmia-related symptom, 24-hour Holter monitoring and portable ECG monitoring Mean follow-up period of 33.8 ± 12.2 months (range, 14 to 54 months) 3 LA stiffness index was an independent predictor of recurrence of AF (HR: 2.88; 95% CI: 1.75 to 4.73, p < 0.001) Good Park et al., 2015* Asia Prospective case series, single centre 334 PVI Direct measurement of LA pulse pressure (the difference between LAP peak and LAP nadir) and assumed a minimal change in LA volume based on the previous physiologic studies ECG and 24- or 48-hour Holter monitoring Mean follow-up period of 16.7 ± 11.8 months (range, 3 to 47 months) NR Low LA compliance was independently associated with two fold-higher risk of clinical AF recurrence (HR: 2.202; 95%CI: 1.077 to 4.503; p = 0.031) Good Kawasaki et al, 2016 Japan Prospective, case series, single centre 109 PVI LA stiffness was obtained by using ePCWP as ePCWP/LA strain obtained by STE ECG and Holter recordings At least 12 months 1 LA stiffness index was not a predictor of recurrence of AF (OR: 0.37, 95%, CI: 0.041 to 3.462, p = 0.39) Good Khurram et al., 2016† North America Prospective, case series, single centre 160 PVI Ratio of change in LAP to the change in LA volume during passive filling of LA. 24-hour Holter monitoring or 30-day event monitoring Mean follow-up period of 10.4 ± 7.6 months 3 LA stiffness index was an independent predictor of AF ablation outcome (HR: 8.22; 95% CI: 3.54 to 19.11; p < 0.001) Good LA: Left atrial; LAP: Left atrial pressure; AF: atrial fibrillation; PVI: pulmonary vein isolation; NR: not reported; ECG: electrocardiogram; global S-LAs: average mean values for peak strain during ventricular systole (S-LAs) obtained from the 4- and 2-chamber views; ePCWP: estimated pulmonary capillary wedge pressure; STE: speckle tracking echocardiography. *The analysis included only the structured normal heart patient population. †Only the 160 patients included for outcome analysis are depicted in this table. 503