Post-AMI diastolic dysfunction is risk factor for new-onset AF
MedWire News: The presence of diastolic dysfunction in people with acute myocardial infarction (AMI) is a risk factor for new-onset atrial fibrillation (AF), study findings suggest.
The researchers suggest that higher filling pressures may increase left atrial pressure and initiate LA remodeling, thereby promoting the development of AF after AMI.
Doron Aronson (Israel Institute of Technology, Haifa) and co-authors recruited 1169 patients with AMI and studied them with echocardiography between 1 and 3 days after admission. Patients were then followed-up for 6 months, during which time 110 (9.4%) developed new-onset AF.
Aronson's team used multivariate models to look for baseline echocardiographic parameters that predicted the development of AF.
Writing in the American Journal of Cardiology, they reveal that a restrictive filling pattern (RFP) - indicative of advanced diastolic dysfunction - was significantly associated with risk for AF, with a hazard ratio (HR) of 2.72.
This association remained significant, with a HR of 2.17, after adjusting for clinical variables, left ventricular ejection fraction, and LA size.
In subgroup analysis, the AF risk conferred by RFP was greatest in patients with a preserved or decreased left ventricular ejection fraction (LVEF), with HRs of 2.14 and 2.80, respectively.
In contrast, a decreased LVEF in the absence of RFP was not associated with an increased risk for AF. This underscores the importance of RFP as a risk factor for subsequent AF, say the authors.
They write: "These results suggest that LV systolic dysfunction with normal or mildly increased filling pressures is not associated with increased propensity for AF."
However they add: "The present analysis is retrospective and thus the results must be regarded as hypothesis-generating and exploratory and require validation in prospective studies."
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By Joanna Lyford