Copyright © 2004 by the European Society of Cardiology.
Clinical research
Doppler flow evaluation can anticipate abnormal left lung perfusion after transcatheter closure of patent ductus arteriosus
a Laboratory of Echocardiography, Heart Institute (InCor), University of São Paulo Medical School, Brazil
b Laboratory of Pathology, Heart Institute (InCor), University of São Paulo Medical School, Brazil
c Hemodynamics and Interventional Cardiology Laboratory, Heart Institute (InCor), University of São Paulo Medical School, Brazil
d Department of Nuclear Medicine, Heart Institute (InCor), University of São Paulo Medical School, Brazil
e Department of Paediatric Cardiology, Heart Institute (InCor), University of São Paulo Medical School, Brazil
f Department of Cardiology and General Director of the Heart Institute, Heart Institute (InCor), University of São Paulo Medical School, Brazil
Received February 25, 2004; revised June 22, 2004; accepted July 8, 2004 * Corresponding author. Tel.: + 55 11 3069 5252; fax: + 55 11 3069 5279 (E-mail: amussisoares{at}terra.com.br).
AIMS: Coil protrusion into the left pulmonary artery (LPA) has been described after transcatheter closure of the patent ductus arteriosus (PDA). The possible impact of such a finding in lung perfusion has not been completely clarified. We evaluated Doppler flow velocities and lung perfusion in patients submitted to that procedure.
METHODS: After transcatheter closure of PDA with coils, 70 patients (mean age 8.6±3.4 years) were followed for a period of 3.6±0.9 years (range 2.1–5.9) and compared to 22 controls. Peak flow velocities and coil protrusion were assessed by Doppler echocardiography. A Doppler velocity index (DVI) was calculated by the difference between the LPA and right pulmonary artery (RPA) peak flow velocities relative to the pulmonary trunk (PT) expressed in percentage, as follows: DVI=(LPA velocity–RPA velocity)/PT velocityx100. Lung scintigraphy was performed using 99mTc-labelled macro-aggregated albumin.
RESULTS: Device protrusion was observed in 94% of the patients, 10% of whom presented abnormal left lung perfusion. Peak LPA velocity and DVI were significantly greater in patients (p=0.001) and correlated negatively with left lung perfusion values (R2=0.21 and R2=0.65, respectively). A cut-off value of 50% for the DVI showed high sensitivity and specificity for reduced lung perfusion.
CONCLUSION: Impaired left lung perfusion may appear following transcatheter closure of PDA with coils and the determination of DVI may anticipate such alteration.