Cardiovascular effects of sildenafil in neonates and infants with congenital diaphragmatic hernia and pulmonary hypertension.
BACKGROUND
Pulmonary hypertension is a common problem in patients with congenital diaphragmatic hernia (CDH). In a subset of these patients, pulmonary hypertension persists despite optimized ventilatory management and supportive care. Sildenafil, a phosphodiestrase V inhibitor, has been used in the treatment of pulmonary hypertension in adults and children. Cardiovascular effects of sildenafil in patients with CDH and pulmonary hypertension are not known.


OBJECTIVE
To describe the changes in cardiovascular and respiratory parameters in newborn infants with CDH and persistent pulmonary hypertension refractory to inhaled nitric oxide (iNO) during the first 2 weeks of sildenafil administration.


METHODS
Retrospective data analysis of seven patients with CDH (birth weight = 2,573 +/- 1,019 g; gestational age = 35.6 +/- 4.3 weeks) receiving oral sildenafil for pulmonary hypertension refractory to iNO. Findings of serial echocardiograms and data on cardiovascular and respiratory status were assessed.


RESULTS
Right cardiac output increased and left cardiac output tended to increase 1.5-4 h after initiation of sildenafil and the increase was sustained throughout the study. Echocardiographic indices of pulmonary hypertension showed an apparent reduction in abnormally high pulmonary vascular resistance. Systemic blood pressure tended to decrease. Shortening fraction did not change. Ventilatory index and the need for iNO tended to decrease in the five surviving infants.


CONCLUSIONS
These preliminary findings suggest that sildenafil may improve cardiac output by reducing pulmonary hypertension refractory to iNO in patients with CDH.
Noori
Shahab
S
USC Division of Neonatal Medicine, Childrens Hospital Los Angeles, Keck School of Medicine, University of Southern California, Los Angeles, CA 90027, USA. snoori@chla.usc.edu
Friedlich
Philippe
P
Wong
Pierre
P
Garingo
Arlene
A
Seri
Istvan
I
D000284:Administration, Oral; D001783:Blood Flow Velocity / Q000187:drug effects; D001794:Blood Pressure / Q000187:drug effects / Q000502:physiology; D002302:Cardiac Output / Q000187:drug effects* / Q000502:physiology; D004562:Electrocardiography; D006548:Hernia, Diaphragmatic / Q000150:complications / Q000503:physiopathology; D006801:Humans; D006976:Hypertension, Pulmonary / Q000150:complications / Q000188:drug therapy* / Q000503:physiopathology; D007223:Infant; D007231:Infant, Newborn; D010726:Phosphodiesterase Inhibitors / Q000627:therapeutic use*; D010879:Piperazines / Q000627:therapeutic use*; D011651:Pulmonary Artery / Q000187:drug effects / Q000502:physiology; D011687:Purines / Q000627:therapeutic use; D012189:Retrospective Studies; D000068677:Sildenafil Citrate; D013450:Sulfones / Q000627:therapeutic use*; D014655:Vascular Resistance / Q000187:drug effects; D014665:Vasodilator Agents / Q000627:therapeutic use*
D010726:Phosphodiesterase Inhibitors; D010879:Piperazines; D011687:Purines; D013450:Sulfones; D014665:Vasodilator Agents; D000068677:Sildenafil Citrate