Objective: Diastolic dysfunction has been associated with
development of atrial fibrillation (AF) in the community and recently in the
postoperative setting. We hypothesized that abnormal left ventricular filling
predicts AF after cardiac surgery, a common marker of poor outcomes.
Methods: Cohort study of 233 consecutive patients, who
underwent coronary artery bypass grafting (CABG) and/or valve surgery. Early and
late mitral inflow velocity (E, A) and deceleration time (DT) and early mitral
annular velocity (e’) obtained from echo within 6 months before cardiac surgery
and their association with postoperative AF.
Results: Postoperative AF occurred in 65 (28%) of patients,
who were on average older, more likely to have had prior episodes of AF, had
larger inferior vena cava diameter and shorter DT (189 ± 62ms vs. 214 ± 63ms,
p=0.007). Multivariable adjusted
analyses demonstrated only DT (odds ratio [OR] 0.65 (95% confidence interval
[CI] 0.40-0.97), older age (OR 2.62 (95% CI 1.68 - 4.10) and prior episodes of
atrial fibrillation (OR 7.20, CI 1.41-36.8) to be independent predictors of
postoperative AF. Patients with a DT ≤ 200ms (n=117) had a significantly longer
length of hospital stay compared with those who had DT > 200ms (n=116)
(median 7 days (interquartile range [IQR] 5-10) vs. 6 days (IQR 5-7, p=0.0002).
Conclusion: In patients who undergo cardiac surgery, a shorter
DT of early mitral inflow identified greater risk for postoperative AF and a
longer hospital stay. These results provide useful information for preoperative
risk assessment and mechanistic understanding of postoperative AF.
Credits: Florian Rader, MD, MSc; Rama Dilip Gajulapalli, MD; Tilak Pasala, MD; Douglas Einstadter, MD, MPH