Management of adults with congenital bidirectional cardiac shunts,cyanosis, and pulmonary vascular obstruction: Successful operative repair in 3 patients

Patients with congenital cardiac shunts in whom marked functional disability, cyanosis and pulmonary arterial hypertension develop have been considered inoperable or at exceedingly high risk. Three adult patients, 2 with atrial septal defect (ASD) and 1 with patent ductus arteriosus (PDA), presented with New York Heart Association class IV symptoms, bidirectional shunting with cyanosis, polycythemia, severe pulmonary hypertension, and increased pulmonary vascular resistance. Pulmonary arterial pressure did not decrease in response to administration of 100% oxygen in any patient, and 2 had lung biopsy results showing advanced pulmonary vascular obstruction. While a right-to-left shunt caused cyanosis in all patients, the net shunt was left to right ($\text{Q}{}_{\mathrm{p}}\text{Q}{}_{\mathrm{s}}\text{> 1}$) and the resistance ratio $\text{(}\text{R}{}_{\mathrm{p}}\text{R}{}_{\mathrm{s}}\text{) <0.5}$. All 3 patients survived operation, became acyanotic with normal hematocrit, and are in functional class I or II a mean of 36 months post-operatively. At repeat cardiac catheterization, pulmonary arterial pressure and resistance had decreased substantially.This high-risk group of patients with bidirectional shunts, in whom cyanosis due to pulmonary vascular obstruction and polycythemia develop and who appear to be at very high operative risk, should still be considered for surgical correction if the usual criteria for operability exist: net left-to-right $\text{Q}{}_{\mathrm{p}}\text{Q}{}_{\mathrm{s}}$ and $\text{R}{}_{\mathrm{p}}\text{R}{}_{\mathrm{s}}\text{<0.50}$.