Clinical utility of echocardiography for the diagnosis and management of pulmonary vascular disease in young children with chronic lung disease

Abstract

Objective: The goal was to determine the clinical utility of Doppler echocardiography in predicting the presence and severity of pulmonary hypertension in patients with chronic lung disease who subsequently underwent cardiac catheterization.

Methods: A retrospective review of data for all patients < 2 years of age with a diagnosis of bronchopulmonary dysplasia, congenital diaphragmatic hernia, or lung hypoplasia who underwent echocardiography and subsequently underwent cardiac catheterization for evaluation of pulmonary hypertension was performed. The accuracy of echocardiography in diagnosing pulmonary hypertension, on the basis of estimated systolic pulmonary artery pressure, was compared with the detection of pulmonary hypertension with the standard method of cardiac catheterization.

Results: Thirty-one linked measurements for 25 children were analyzed. Systolic pulmonary artery pressure could be estimated in 61% of studies, but there was poor correlation between echocardiography and cardiac catheterization measures of systolic pulmonary artery pressure in these infants. Compared with cardiac catheterization measurements, echocardiographic estimates of systolic pulmonary artery pressure diagnosed correctly the presence or absence of pulmonary hypertension in 79% of the studies in which systolic pulmonary artery pressure was estimated but determined the severity of pulmonary hypertension (severe pulmonary hypertension was defined as pulmonary/systemic pressure ratio of > or = 0.67) correctly in only 47% of those studies. Seven (58%) of 12 children without estimated systolic pulmonary artery pressure demonstrated pulmonary hypertension during subsequent cardiac catheterization. In the absence of estimated systolic pulmonary artery pressure, qualitative echocardiographic findings, either alone or in combination, had worse predictive value for the diagnosis of pulmonary hypertension.

Conclusion: As used in clinical practice, echocardiography often identifies pulmonary hypertension in young children with chronic lung disease; however, estimates of systolic pulmonary artery pressure were not obtained consistently and were not reliable for determining the severity of pulmonary hypertension.

Figure 1

Relationship between sPAP values estimated with echocardiography (ECHO) and directly measured with cardiac catheterization (CATH).

Figure 2

Echocardiography (ECHO)-estimated sPAP values according to severity of PH diagnosed with cardiac catheterization (CATH). PH was defined as mPAP of >25 mm Hg, mild/moderate PH was defined as PH with a mPAP/mean systemic arterial pressure ratio of <0.67, and severe PH was defined as PH with a mPAP/mean systemic arterial pressure ratio of ≥0.67. There were no significant differences between the mean sPAP values of the 3 groups according to analysis of variance.

Figure 3

Ability of echocardiography (ECHO)-estimated sPAPto predict the severity of PH determined with cardiac catheterization (CATH). PH was defined as estimated sPAP of >40 mm Hg in the presence of a measurable TRJV with echocardiography and as mPAP of >25 mm Hg during cardiac catheterization, mild/moderate PH was defined as PH with an estimated sPAP/sBP ratio of <0.67 with echocardiography and a mPAP/mean systemic arterial pressure ratio of <0.67 with cardiac catheterization, and severe PH was defined as PH with an estimated sPAP/sBP ratio of ≥0.67 with echocardiography and a mPAP/mean systemic arterial pressure ratio of ≥0.67 with cardiac catheterization.