Trepopnea

Specialty: Cardiovascular.

• dyspnea in unilateral lateral decubitus position
• postural intolerance to lateral decubitus

Why it occurs

• Unilateral asymmetric left ventricular dysfunction
• Pedunculated atrial myxoma with positional obstruction of the atrioventricular valve
• Unilateral diaphragmatic paralysis
• Massive unilateral pleural effusion (typically of decompensated cardiac origin)
• Severe unilateral lung disease with altered position-dependent ventilation-perfusion relationship
• Extrinsic compression of the heart by postural mediastinal masses

Initial workup

Transthoracic echocardiogram in supine position and lateral decubitus to evaluate the mobility of intracavitary masses (such as atrial myxomas) or dynamic obstruction of the ventricular inflow or outflow tract; Chest x-ray to identify massive unilateral pleural effusions, atelectasis, or elevation of the hemidiaphragm due to paralysis; High-resolution chest computed tomography to evaluate the mediastinum and rule out masses that compress cardiac cavities or the tracheobronchial tree; Diaphragmatic ultrasound.

Standard management

• Furosemide — loop diuretic indicated if trepopnea is aggravated by massive pleural effusion or asymmetric pulmonary congestion of cardiac origin; 40 mg intravenously or orally daily
• Acetylsalicylic acid — maintenance antiplatelet in patients with coronary artery disease causing segmental myocardial dysfunction; 100 mg once a day orally
• Nitroglycerin — coronary vasodilator useful to reduce left ventricular filling pressures during positional episodes; 1 to 2 sublingual sprays of 0.4 mg in case of dyspnea attacks with suspected ischemic
• Enoxaparin (indicated if associated intracavitary thrombus is confirmed; 1 mg/kg subcutaneously every 12 hours).