The widespread heart rhythm disorder atrial fibrillation (AF) results in a significant disease burden with potentially
severe consequences for the indiviual patient and is a problem for health systems worldwide. With the proposed
study, we will gain more insight into the mechanisms that trigger the onset of AF, helping to develop more focused
and effective methods for prevention.
Background: AF is common following coronary artery bypass surgery (CABG), with an incidence of 25-40%. It is
associated with higher mortality rates in addition to increased risks for congestive heart failure and stroke. Post-
operative AF and its complications are associated with prolonged hospital stay and significantly higher costs of
care. Preliminary data suggested that the prediction of AF can be significantly enhanced by assessment of diastolic
function status and left atrial (LA) volume.
Objective: The first aim of this project is to determine prospectively whether pre-CABG assessment of diastolic
function and LA volume enhances prediction of post-CABG AF. The second aim of the study is to determine the
relationship between sympathetic activation, as measured by levels of plasma catecholamines and fractionated
metanephrines, and development of post-CABG AF.
Methods: Patients scheduled for CABG over the first 18 months of the 2-year study period will be invited to
participate. The target sample size is 800 subjects. Pre-operative echocardiograms and ECG will be performed and
a blood sample obtained. Plasma catecholamines and metanephrines will be reassessed 24-hours after surgery.
Monitoring by telemetry will be performed and any AF detection will be confirmed with a 12-lead ECG.