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Relationship between pulmonary artery acceleration time and pulmonary artery pressures in infants
Jessica S Gaulton1, Laura M Mercer-Rosa2, Andrew C Glatz2
1Neonatology, Children's Hospital of Philadelphia, University of Pennsylvania Perelman School of Medicine, Philadelphia, Pennsylvania, USA.
Insights
Pulmonary artery acceleration time (PAAT) shows a weak inverse correlation with pulmonary artery pressures in infants. This relationship is less reliable in infants with patent ductus arteriosus (PDA), suggesting PAAT may be less useful for diagnosing pulmonary hypertension in this group.
Area of Science:
- Pediatric Cardiology
- Neonatology
- Echocardiography
Background:
- Pulmonary artery acceleration time (PAAT) inversely correlates with pulmonary artery pressures in older children and adults.
- Data on this relationship in young infants, especially preterm infants, is limited.
Purpose of the Study:
- To characterize the relationship between PAAT and pulmonary artery pressures in infants.
- To assess the utility of PAAT in diagnosing pulmonary hypertension in neonates and infants.
Main Methods:
- Retrospective review of infants ≤ 1 year of age undergoing echocardiography and cardiac catheterization.
- Exclusion of infants with congenital heart disease, except for PDA, ASD, or VSD.
- Linear regression analysis to correlate PAAT with systolic pulmonary artery pressure (sPAP), mean pulmonary artery pressure (mPAP), and indexed pulmonary vascular resistance (PVRi).
Main Results:
- Fifty-seven infants were included; 61% were preterm and 77% had a PDA.
- A weak inverse correlation was found between PAAT and mPAP (r = -0.35), sPAP (r = -0.29), and PVRi (r = -0.29).
- The correlation was less robust compared to studies in older children, likely due to a high incidence of PDAs.
Conclusions:
- The inverse relationship between PAAT and pulmonary artery pressures is weak in infants.
- PAAT may have limited clinical utility for diagnosing pulmonary arterial hypertension in infants, particularly those with PDAs.
- Further research is needed to establish reliable non-invasive markers for pulmonary hypertension in this population.
Background:
Pulmonary artery acceleration time measured by echocardiography inversely correlates with pulmonary artery pressures in adults and children older than 1 year of age. There is a paucity of data investigating this relationship in young children, particularly among preterm infants.
Objective:
To characterize the relationship between pulmonary artery acceleration time (PAAT) and pulmonary artery pressures in infants.
Design/Methods:
Patients ≤ 1 year of age at Children's Hospital of Philadelphia between 2011 and 2017 were reviewed. Infants with congenital heart disease were excluded, except those with a patent ductus arteriosus (PDA), atrial septal defect (ASD), or ventricular septal defect (VSD). Linear regression analysis was used to assess the correlation between PAAT measured by echocardiography and systolic pulmonary artery pressure, mean pulmonary artery pressure, and indexed pulmonary vascular resistance from cardiac catheterization.
Results:
Fifty-seven infants were included, of which 61% were preterm and 49% had a diagnosis of bronchopulmonary dysplasia. The median postmenstrual age and weight at catheterization were 51.1 weeks (IQR 35.8-67.9 weeks) and 4400 g (IQR 3100-6500 g), respectively. Forty-four infants (77%) had a patent ductus arteriosus (PDA). There was a weak inverse correlation between PAAT with mPAP (r = -0.35, P = 0.01), sPAP (r = -0.29, P = 0.03), and PVRi (r = -0.29, P = 0.03).
Conclusion:
There is a weak inverse relationship between PAAT and pulmonary artery pressures. This relationship is less robust in our population of infants with a high incidence of PDAs compared to previous studies in older children. Thus, PAAT may be less clinically meaningful for diagnosing pulmonary arterial hypertension in infants, particularly those with PDAs.
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