Safety of inhaled nitric oxide withdrawal in severe chronic pulmonary hypertension.

Inhaled nitric oxide (iNO) is a potent and selective pulmonary vasodilator with a safety concern due to rebound pulmonary hypertension (PH) associated with its withdrawal. We report short-term pulsed iNO in patients with severe pulmonary arterial hypertension (PAH) and nonoperable chronic thromboembolic PH (nCTEPH). This is a retrospective analysis of 33 patients: 22 with PAH and 11 with nCTEPH. We assessed hemodynamic, echocardiographic, and other noninvasive variables to evaluate safety and efficacy of iNO. We performed an iNO withdrawal test during right heart catheterization and after 3 days of iNO treatment. iNO significantly improved all variables examined in 22 patients with PAH and 11 with nCTEPH. Two patterns of response were observed after sudden iNO withdrawal. Twenty-nine patients (88%) showed minimal hemodynamic, oxygenation and clinical changes. Four patients (12%) had a reduction in cardiac index ≥20% and PaO2 ≥ 5%, three patients did not show clinical deterioration, and one patient developed hemodynamic collapse that needed iNO administration. This retrospective study suggests that short-term iNO improves hemodynamics and clinical conditions in some patients with PAH an nCTPEH. However, pulsed iNO withdrawal PH rebound could be a serious concern in these patients. Given the lack of evidence, we do not recommend the use of pulsed iNO in the treatment of patients with chronic PH.

Real-life experience of inhaled iloprost for patients with pulmonary arterial hypertension: Insights from the Spanish REHAP registry.

INTRODUCTION: REHAP is a voluntary, observational Spanish registry of patients with pulmonary arterial hypertension. We analyzed the experience (use and effectiveness) with inhaled iloprost (inh-ILO) in real-life conditions during a 3-year period. METHODS: Patients included were those with PAH ≥14 years recruited during 1998-2016 who had received inh-ILO. Variables were collected at the beginning of treatment (0 ±â€¯3 months) and 12 ±â€¯3/36 ±â€¯6 months follow-up. Effectiveness was assessed in the intent-to-treat population as changes in functional class and/or physical performance and transplant-free survival from the beginning of treatment. Stopping inh-ILO-related survival was also assessed. Subanalyses included treatment strategy (first-line therapy -monotherapy or upfront combination- or sequential therapy) and risk of clinical worsening/death. RESULTS: Inh-ILO was the most frequently used prostanoid in Spain, rendering 267 patients eligible for analysis. Median age was 54 years; 61% were WHO FC III. Sixty (23%) patients started inh-ILO as monotherapy, 27 (10%) as upfront combination and 180 (67%) sequentially. At 3-year follow-up significant clinical improvements were observed; however, transplant-free survival rate was 54%, being poorer in patients at high risk (63% vs. 85% in low risk patients; P < 0.001) and similar in the three treatment strategies. Only 25% patients remained on inh-ILO. Three-year after stopping inh-ILO-related survival rate was 24.7%. CONCLUSION: Data from the REHAP collected during 3 years shows that inh-ILO has low effectiveness independently of the treatment strategy used, with a 3-year survival rate of 54% despite significant clinical improvements, probably due to the use in high-risk patients. Discontinuation rate was as high as 75%.

Pulmonary Arterial Hypertension in Systemic Lupus Erythematosus: Prevalence and Predictors.

OBJECTIVE: Pulmonary arterial hypertension (PAH) prevalence has been reported to be between 0.5% and 17% in systemic lupus erythematosus (SLE). This study assessed PAH prevalence and predictors in an SLE cohort. METHODS: The Borg dyspnea scale, DLCO, N-terminal pro-brain natriuretic peptide (NT-proBNP), and Doppler echocardiographic (DE) were performed. An echocardiographic Doppler exercise test was conducted in selected patients. When DE systolic pulmonary arterial pressure was ≥ 45 mmHg or increased during exercise > 20 mmHg, a right heart catheterization was performed. Hemodynamic during exercise was measured if rest mean pulmonary arterial pressure was < 25 mmHg. RESULTS: Of the 203 patients with SLE, 152 were included. The mean age was 44.9 ± 12.3 years, and 94% were women. Three patients had known PAH. The algorithm diagnosed 1 patient with chronic thromboembolic pulmonary hypertension and 5 with exercise-induced pulmonary artery pressure increase (4 with occult left diastolic dysfunction). These patients had significantly more dyspnea, higher NT-proBNP, and lower DLCO. CONCLUSION: These data confirm the low prevalence of PAH in SLE. In our cohort, occult left ventricular diastolic dysfunction was a frequent diagnosis of unexplained dyspnea. Dyspnea, DLCO, and NT-proBNP could be predictors of pulmonary hypertension in patients with SLE.

Long-term inhaled nitric oxide plus phosphodiesterase 5 inhibitors for severe pulmonary hypertension.

BACKGROUND: Inhaled nitric oxide (iNO) is a potent pulmonary vasodilator, but therapeutic experience in patients with severe pulmonary hypertension is scarce. METHODS: Eleven patients with severe pulmonary hypertension, 6 due to pulmonary arterial hypertension and 4 due to chronic thromboembolic disease, were selected for iNO therapy. A phosphodiesterase type 5 inhibitor (PDE5i) was added in cases of clinical worsening. In this study we evaluate the clinical effectiveness and safety of long-term treatment with iNO either alone or combined with a PDE5i. RESULTS: After 1 month of iNO administration, improvements were observed in World Health Organization functional class, Borg scale (p = 0.003), brain natriuretic peptide levels (p = 0.002) and 6-minute walk test (p = 0.003). After 6 months of treatment, 7 patients had clinical deterioration that was reversed upon adding a PDE5i. One of these patients died in Month 8 and another underwent pulmonary transplantation in Month 9. The clinical condition of the remaining 9 patients was unchanged after 1 year. A second right catheterization showed improvement in mean pulmonary arterial pressure (66 +/- 15 mm Hg to 56 +/- 18 mm Hg; p = 0.01), pulmonary vascular resistance (1,234 +/- 380 dyn/s/cm(5) to 911 +/- 410 dyn/s/cm(5); p = 0.008) and cardiac index (2.0 +/- 0.4 liters/min/m(2) to 2.5 +/- 0.4 liters/min/m(2); p = 0.04). There was no significant increase in methemoglobin, no worsening of pulmonary function and no sudden withdrawal syndrome. CONCLUSIONS: We suggest that iNO therapy alone or in combination with a PDE5i could be a therapeutic alternative for severe pulmonary hypertension.