orthopnoe

Orthopnoe, also spelled orthopnea, is a form of dyspnea that occurs when a person lies flat and is relieved by sitting up or standing. It is a common presenting symptom in conditions that cause fluid overload or impaired left ventricular function, most notably congestive heart failure. The condition reflects an increase in venous return and left-sided heart pressures when recumbent, leading to pulmonary congestion.

Causes and pathophysiology: Orthopnoe most often results from left heart failure or severe mitral valve disease, where elevated left atrial and pulmonary capillary pressures worsen during lying down. It can also occur with constrictive pericarditis, obesity, pregnancy, and, less commonly, advanced chronic lung or neuromuscular diseases that affect respiratory mechanics. The symptom classically improves upon adopting an upright position.

Clinical features: Patients describe breathlessness that starts or worsens within minutes of lying flat and improves when they sit up or prop themselves with pillows. It is frequently associated with paroxysmal nocturnal dyspnea, a sudden nocturnal episode of breathlessness relieved by waking and upright positioning. Other signs of heart failure, such as edema, elevated jugular venous pressure, and basilar crackles, may be present.

Diagnosis and evaluation: Diagnosis relies on history and physical examination, supported by investigations. Chest imaging, echocardiography to assess cardiac structure and function, and natriuretic peptides (BNP or NT-proBNP) help differentiate cardiac from non-cardiac causes of dyspnea.

Management: Treatment targets the underlying cause and may include diuretics to reduce preload, optimization of heart failure therapy, and positional measures (elevating the head of the bed). In acute settings, supplemental oxygen and noninvasive ventilation may be used; addressing comorbid conditions is important for prognosis.

Prognosis: Orthopnoe is a marker of significant cardiopulmonary dysfunction and often indicates advanced disease; response to therapy depends on the underlying etiology and overall cardiovascular status.