Author + information
- Received April 10, 1998
- Revision received September 18, 1998
- Accepted October 30, 1998
- Published online March 1, 1999.
- ↵*Reprint requests and correspondence: Dr. David L. Wessel, Cardiac ICU Office, Farley 653, Children’s Hospital, 300 Longwood Avenue, Boston, Massachusetts 02115
We compared the ability of inhaled nitric oxide (NO), oxygen (O2) and nitric oxide in oxygen (NO+O2) to identify reactive pulmonary vasculature in pulmonary hypertensive patients during acute vasodilator testing at cardiac catheterization.
In patients with pulmonary hypertension, decisions regarding suitability for corrective surgery, transplantation and assessment of long-term prognosis are based on results obtained during acute pulmonary vasodilator testing.
In group 1, 46 patients had hemodynamic measurements in room air (RA), 100% O2, return to RA and NO (80 parts per million [ppm] in RA). In group 2, 25 additional patients were studied in RA, 100% O2and 80 ppm NO in oxygen (NO+O2).
In group 1, O2decreased pulmonary vascular resistance (PVR) (mean ± SEM) from 17.2 ± 2.1 U·m2to 11.1 ± 1.5 U·m2(p < 0.05). Nitric oxide caused a comparable decrease from 17.8 ± 2.2 U·m2to 11.7 ± 1.7 U·m2(p < 0.05). In group 2, PVR decreased from 20.1 ± 2.6 U·m2to 14.3 ± 1.9 U·m2in O2(p < 0.05) and further to 10.5 ± 1.7 U·m2in NO+O2(p < 0.05). A response of 20% or more reduction in PVR was seen in 22/25 patients with NO+O2compared with 16/25 in O2alone (p = 0.01).
Inhaled NO and O2produced a similar degree of selective pulmonary vasodilation. Our data suggest that combination testing with NO+O2provides additional pulmonary vasodilation in patients with a reactive pulmonary vascular bed in a selective, safe and expeditious fashion during cardiac catheterization. The combination of NO+O2identifies patients with significant pulmonary vasoreactivity who might not be recognized if O2or NO were used separately.
☆ Dr. Atz is supported by an award from the National Institutes of Child Health and Human Development and a grant from the United States Food and Drug Administration. Dr. Wessel is supported by grants from the United States Food and Drug Administration and the Research Endowment of Children’s Hospital.
Presented in part at the 45th Annual Scientific Sessions of the American College of Cardiology, Orlando, Florida, March 1996.
- Received April 10, 1998.
- Revision received September 18, 1998.
- Accepted October 30, 1998.
- American College of Cardiology