Persistence of pulmonary arterial hypertension after relief of left sided obstructive lesions in small infants: our experience

BACKGROUND: Infants with critical left sided obstructive lesions usually present with left ventricle dysfunction and pulmonary arterial hypertension (PAH). Left ventricular dysfunction and pulmonary artery pressures usually normalize after relief of obstruction. In some, PAH persists despite adequate relief of obstruction. PATIENTS AND METHODS: We retrospectively reviewed records of infants (less than 3 months) who underwent intervention for left sided obstruction (n=50) over four years (May 2012–May 2016). RESULT: We report four infants who had persistent of PAH despite relief of left sided obstruction. The causes of PAH were found to be high left ventricular end diastolic pressure(n=1), severe hypoplasia of pulmonary veins (n=1), stenosis of the lower branch of the right pulmonary artery (n=1) and non-regression of pulmonary vascular resistance (n=1). CONCLUSION: That persistence of PAH after relief of obstruction should be investigated and other, less common causes should be sought.