Aims: Enhanced platelet activity assessed by mean platelet volume (MPV) was observed in pulmonary arterial hypertension. This study examined the presence of platelet activation in adults with atrial septal defect (ASD), its relationship with pulmonary vascular disease and its changes following device closure of the defects.
Methods: A total of 76 consecutive patients received transcatheter ASD closure and 40 matched healthy volunteers were prospectively enrolled for blood tests and transthoracic echocardiography (patients: aged 36 ± 13, 37% men; controls: aged 36 ± 8, 38% men). MPV, systolic pulmonary arterial pressures (PAP), and right ventricular end-diastolic diameters were collected before and after ASD closure in patients.
Results: The mean MPV levels were significantly higher in patients than in controls (10.1 ± 1.3 to 8.6 ± 0.9 fl; P < 0.001) at baseline. A moderate, positive correlation was also observed between baseline MPV levels and systolic PAP (r = 0.542, P < 0.001) in patients. Both MPV levels, systolic PAP and right ventricular end-diastolic diameters reduced significantly 6 months following ASD closure. The 6-month MPV and systolic PAP values were comparable to those of the normals.
Conclusion: Enhanced platelet activity was present in ASD and associated with the presence of pulmonary vascular disease. This phenomenon was largely reversible following device closure of the defects.