Chronic exposure to high altitude 4. Chronic thromboembolic pulmonary hypertension/other pulmonary artery obstructions
Other pulmonary artery obstructions, i.e., tumors, arteritis, pulmonary stenosis, parasites 5. Pulmonary hypertension with unclear and/or multifactorial mechanisms
Hematological disorders: chronic hemolysis, myeloproliferative disorders, splenectomy Systemic disorders: sarcoidosis, pulmonary histiocytosis, neurofibromatosis
Metabolic disorders: glycogen storage disease, Gaucher disease, thyroid disorders Others: fibrosing mediastinitis, chronic renal failure
HIV = human immunodeficiency virus. Adapted from Galie, 2016.
have pulmonary hypertension (Rich, 2005). Other causes in young women are human immunodeiciency virus (HI) infection, sickle-cell disease, and thyrotoxicosis (Newman, 2015; Sheield, 2004).
In pregnant women, group 2 disorders are the most common. hese are secondary to pulmonary venous hypertension caused by left-sided atrial, ventricular, or valvular disorders. A typical example is mitral stenosis discussed earlier (p. 955). In contrast, groups 3 through 5 are seen infrequently in young healthy women .
Symptoms may be vague, and dyspnea with exertion is the most frequent. With group 2 disorders, orthopnea and nocturnal dyspnea are also usually present. Angina and syncope occur when right ventricular output is ixed, and they suggest advanced disease. Chest radiography often shows enlarged pulmonary hilar arteries and attenuated peripheral markings. It also may disclose parenchymal causes of hypertension. N oninvasive echocardiography can provide an estimate of pulmonary artery pressures, although cardiac catheterization remains the standard for measurement. In two studies with a combined 51 pregnant women who underwent both echo cardiography and cardiac catheterization, pulmonary artery pressures were significantly overestimated by echocardiography in approximately one third of cases (Penning, 2001; Wylie, 2007).
Regardless of the etiology, the inal common pathway of pulmonary hypertension is right heart failure and death. he average survival length after diagnosis is <4 years (Krexi, 2015). That said, longevity depends on the severity and cause of pulmonary hypertension at discovery. As discussed later, some disorders respond to medical interventions, which may improve quality of life. Preconceptional and contraceptive counseling are imperative (Gei, 2014).
he maternal mortality rate is appreciable in afected women, and this is especially so with idiopathic pulmonary hypertension. In the past, there were frequently poor distinctions in identiying both causes and severity of hypertension. hus, although most severe cases of idiopathic pulmonary arterial hypertension had the worst prognosis, it was erroneously assumed that all types of pulmonary hypertension were equally dangerous. With widespread use of echocardiography, lesssevere lesions with a better prognosis are now discernible. Bedard and coworkers (2009) reported that maternal mortality rate statistics improved during the decade ending in 2007 (25 percent) compared with those for the decade ending in 1996 (38 percent). Importantly, almost 80 percent of the deaths were during the first month postpartum. More recently, Meng and associates (2017) reported mortality rates of 23 percent with group 1 and 5 percent with the other groups. Mortality was related to pulmonary hypertension severity.