Inhaled Nitric Oxide as a Preoperative Test (INOP Test I)

Abstract

Background This study was performed to determine whether a preoperative hemodynamic evaluation with oxygen and inhaled nitric oxide identifies patients with pulmonary hypertension who are appropriate candidates for corrective cardiac surgery or transplantation more accurately than an evaluation with oxygen alone. Methods and Results At 10 institutions, 124 patients with heart disease and severe pulmonary hypertension underwent cardiac catheterization to determine operability. The ratio of pulmonary and systemic vascular resistance (Rp:Rs) was determined at baseline while breathing ∼21% to 30% oxygen, and in ∼100% oxygen and ∼100% oxygen with 10 to 80 parts per million nitric oxide to evaluate pulmonary vascular reactivity. Surgery was performed in 74 patients. Twelve patients died or developed right heart failure secondary to pulmonary hypertension following surgery. Rp:Rs<0.33 and a 20% decrease in Rp:Rs from baseline were chosen as 2 criteria for operability to determine, in retrospect, the efficacy of preoperative testing in patient selection. In comparison to an evaluation with oxygen alone, sensitivity (64% versus 97%) and accuracy (68% versus 90%) were increased by an evaluation with oxygen and nitric oxide when Rp:Rs<0.33 was used as the criterion for operability. Specificity was only 8% when a 20% decrease in Rp:Rs from baseline was used as the criterion for operability. Conclusion By using a combination of oxygen and inhaled nitric oxide, a greater number of appropriate candidates for corrective cardiac surgery or transplantation can be identified during preoperative testing when a specific value of Rp:Rs is used as a criterion for operability.

Effect on Pulmonary Atery Presssres after Transcatheter Occlusion of Patent Ductus Arteriosus with Severe Pulmonary Artery Hypertension

“…However, if the clinical tests are ambiguous and there are certain restrictions for computing PVR in PDA, it might be challenging to decide whether to act (16). The use of vasodilators, including inhaled nitric oxide, has little usefulness in determining operability, according to multicenter research by Balzar et al (15). Contrary to widespread perception, a recent study revealed that postoperative outcome did not correspond with preoperative hemodynamic data for a variety of reasons.…”

“…A difficult clinical issue is whether to attempt TCC of PDA in patients with severe PAH. If the severe PAH is reversible, it will be the main factor in care and prognosis in this disease (15). A clinical examination is done to assess if severe PAH is reversible.…”

Long-Term Follow-Up of Pediatric Patients with Severe Postoperative Pulmonary Hypertension After Correction of Congenital Heart Defects

“…However, the decision to perform cardiac surgery proved successful in all three children, indicating that the PVR was indeed reversible. It also emphasized the findings by several authors that there is no association between preoperative PVRI and outcome [ 10 , 11 ] and that the response to vasodilator testing showing reversibility has no prognostic implication, published in the 5th World Symposium on pulmonary hypertension in Nice, France, 2013 [ 11 , 12 ].…”

“…There is no association between preoperative PVR and outcome, which is in accordance with our findings [ 10 , 11 ]; furthermore it does not predict the need for pulmonary vasodilators after cardiopulmonary bypass [ 31 ]. The notion that it is important to show the ability of reversibility of PVR by pulmonary vasodilating drugs has shown to be of no prognostic implication, as published in the 5th World Symposium on pulmonary hypertension in Nice, France, 2013 [ 11 , 12 ]. In addition, any reversibility can be considered to be included in the clinical history and the non-invasive diagnostic evaluation by echocardiography [ 11 ].…”

Pulmonary Hypertension in Congenital Heart Disease: A Scientific Statement From the American Heart Association

“…When available, inhaled nitric oxide (20-80 ppm) alone or in combination with oxygen is considered the preferred agent for vasodilator testing. 79,[81][82][83] It is safe and short acting and offers a better pulmonary vasodilator effect than systemic agents. However, nitric oxide is not always affordable and thus is not readily available in all cardiac catheterization laboratories, particularly in low-to middleincome countries.…”