Atrial Septal Defects Accelerate Pulmonary Hypertension Diagnoses in Premature Infants
Shilpa Vyas-Read1, Lokesh Guglani1, Prabhu Shankar2
1Department of Pediatrics, Emory University, Atlanta, GA, United States.
Insights
Extremely premature infants with atrial septal defects (ASD) are more than twice as likely to develop pulmonary hypertension (PH). Close monitoring for PH in these infants is crucial for timely intervention and improved outcomes.
Area of Science:
- Neonatology
- Pediatric Cardiology
- Pulmonary Medicine
Background:
- Late pulmonary hypertension (PH) affects 4-16% of extremely premature infants, increasing risks of tracheostomy and mortality.
- Atrial septal defects (ASD) can augment pulmonary blood flow, potentially exacerbating PH risk in vulnerable infants.
Purpose of the Study:
- To investigate whether infants with an atrial septal defect (ASD) develop pulmonary hypertension (PH) earlier than those without ASD.
- To determine the association between ASD and the time to PH diagnosis in extremely premature infants.
Main Methods:
- Retrospective analysis of extremely premature infants (<32 weeks' gestation) with echocardiograms after 30 days of life.
- Comparison of time to PH diagnosis between infants with and without ASD using multivariable and Cox proportional hazard models.
Main Results:
- Infants with ASD had a significantly higher incidence of PH (26% vs. 12%, p=0.006).
- Infants with PH had lower gestational age, smaller birthweight, and more prematurity complications.
- Controlled for clinical variables, infants with ASD had a 2.44-fold increased hazard for developing PH (95% CI 1.27-4.68).
Conclusions:
- Atrial septal defects are associated with an increased hazard and earlier onset of pulmonary hypertension in extremely premature infants.
- Close surveillance for PH development is recommended in premature infants diagnosed with ASD.
- Further research is needed to determine optimal timing for ASD closure in this population.
Abstract:
Between 4 and 16% of extremely premature infants have late pulmonary hypertension (PH) (onset >30 days of life), and infants with PH have a higher risk of tracheostomy and death. Atrial septal defects (ASD) increase pulmonary blood flow and may promote PH in at-risk infants. The objective of this study was to determine if infants with ASD develop PH sooner than those without ASD. Infants who were born at < 32 weeks' gestation, with an echocardiogram on day of life > 30, and without congenital anomalies were included. Infants with and without ASD were evaluated for the time to PH diagnosis, defined as the day of the first echocardiogram that showed PH. A multivariable model with ASD and significant variables on PH and a Cox proportional hazard model evaluating time to PH was determined. Of the 334 infants with echocardiograms, 57 had an ASD and 26% of these developed PH vs. 12% without ASD (p = 0.006). Infants with PH had lower gestational age (25.2 vs. 26.2 weeks, p = 0.005), smaller birthweight (699 vs. 816 gm, p = 0.001), and more prematurity complications than infants without PH. More PH infants had maternal African-American race (63.9 vs. 36.1%), right ventricular dysfunction (23.9 vs. 3.2%, p < 0.001), right ventricular dilation (52.1 vs. 8.6%, p < 0.001), or right ventricular hypertrophy (51.2 vs. 10.1%, p < 0.001), than infants without PH. At 150 days of life, 78.1% (95% CI 64.6-86.9%) of infants with ASD survived without PH, compared with 90.9% (95% CI 86.7-93.8%) of infants without ASD, and the unadjusted hazard for development of PH for infants with ASD was 2.37 (95% CI 1.29-4.36). When significant clinical variables were controlled, infants with ASD had a 2.44-fold (95% CI 1.27-4.68) increase in PH, compared with infants without ASD. Most PH in infants with or without ASD was diagnosed by day of life 150, but infants with ASD had an over 2-fold increased hazard for PH during their neonatal hospitalization. Premature infants with ASD should be followed closely for PH development and further studies to investigate the optimal timing of closure are needed.
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