High Altitude Pulmonary Hypertension

High Altitude Pulmonary Edema (HAPE) is a critical, non-cardiogenic pulmonary edema that manifests in high-altitude conditions, marked by the rapid onset of symptoms such as dyspnea, cough, frothy sputum, and cyanosis. It represents a significant cause of mortality among high-altitude illnesses due to its swift progression and elevated fatality rates if not addressed promptly. The pathophysiological mechanisms underlying HAPE include excessive hypoxic pulmonary vasoconstriction, increased permeability of the pulmonary vasculature, impaired clearance of fluid from the lungs, and systemic fluid retention. A pivotal factor in HAPE is pulmonary arterial hypertension (PAH), characterized by a progressive rise in pulmonary arterial pressure and resistance, which can ultimately lead to right heart failure. Recent developments in the management of HAPE have introduced inhaled nitric oxide (iNO) as a selective pulmonary vasodilator, which effectively lowers pulmonary arterial pressure and enhances oxygenation without inducing systemic hypotension. The INOwill N300 device, created by Nanjing Novlead Biotech, is a portable iNO delivery system that produces nitric oxide gas on-site, thereby obviating the need for gas cylinders. This device also facilitates real-time monitoring of nitric oxide, nitrogen dioxide, and oxygen concentrations, ensuring safe and effective treatment. This innovative strategy shows potential for improving clinical outcomes in patients with HAPE while addressing logistical challenges encountered in high-altitude environments.

The purpose of the current study is to evaluate the clinical and physiologic course of Kyrgyz highlanders with high altitude pulmonary hypertension (HAPH) by performing a longitudinal cohort study. To this end, the investigators will invite the same highlanders who participate din the study in 2017 to undergo follow-up examinations in 2024, in order to allow comparisons of current results with baseline data from 2017.