title: Single beat determination of regional myocardial strain measurements in patients with atrial fibrillation.
abstract: Atrial fibrillation (AF) and congestive heart failure share several features and often coexist in the same patients; therefore, serial assessment of regional myocardial function is important for patients with AF. However, the clinical assessment of regional myocardial function in AF is unreliable and difficult because of beat-to-beat variation. Recent reports have shown that the ratio of the preceding to the prepreceding R-R interval (RR1/RR2) can be used to assess global left ventricular systolic function. Accordingly, we tested the hypothesis that regional wall motion can be estimated from a single beat based on RR1/RR2 in patients with AF. Peak systolic strain at basal, mid, and apical segments of the septal wall was measured by Doppler tissue imaging from an apical 4-chamber view for 30 seconds in 50 patients with AF (mean ejection fraction 52.1 +/- 15.3%; mean heart rate 76.4 +/- 16.0/min). There was a positive linear relationship between peak strain and RR1/RR2 and RR1, and a negative relationship with RR2, with the correlation of peak strain to RR1/RR2 was better than that in RR1 or RR2. Furthermore, peak strain at RR1/RR2 = 1 was calculated from the linear regression and compared with the average measured value of all recorded cardiac cycles in each patient. In all cases, average peak strain showed a significant positive correlation with RR1/RR2 at each segment (r = 0.99). In conclusion, regional myocardial strain at RR1/RR2 = 1 on the linear regression represents the average value of all recorded cardiac cycles in patients with AF.
authors.affiliation: First Department of Internal Medicine, Mie University School of Medicine, Tsu, Japan.
authors.forename: Kaoru
authors.initials: K
authors.lastname: Yamanaka-Funabiki
authors.forename: Katsuya
authors.initials: K
authors.lastname: Onishi
authors.forename: Masaki
authors.initials: M
authors.lastname: Tanabe
authors.forename: Kaoru
authors.initials: K
authors.lastname: Dohi
authors.forename: Masaaki
authors.initials: M
authors.lastname: Ito
authors.forename: Nobuyuki
authors.initials: N
authors.lastname: Ohte
authors.forename: Tsutomu
authors.initials: T
authors.lastname: Nobori
authors.forename: Takeshi
authors.initials: T
authors.lastname: Nakano
mesh_terms: D000368:Aged; D001281:Atrial Fibrillation / Q000150:complications / Q000000981:diagnostic imaging* / Q000503:physiopathology*; D015150:Echocardiography, Doppler / Q000379:methods*; D004548:Elasticity; D005260:Female; D006339:Heart Rate; D006801:Humans; D007090:Image Interpretation, Computer-Assisted / Q000379:methods*; D008297:Male; D013314:Stress, Mechanical; D018487:Ventricular Dysfunction, Left / Q000150:complications / Q000000981:diagnostic imaging* / Q000503:physiopathology*