Diaphragmatic paralysis: A clinical imitator of cardiorespiratory diseases

Diaphragmatic paralysis has a predictable effect on lung function. However, the symptoms depend on the preexisting heart-lung diseases and may mimic various cardiorespiratory processes. We describe the presentation in six patients. In a fit man, unilateral diaphragmatic paralysis caused dyspnea only at strenuous exercise. In a patient with emphysema it caused dyspnea mainly when carrying light weights. In another patient with emphysema it caused life-threatening hypoxemia simulating parenchymal lung disease. A patient with mild chronic obstructive lung disease and nocturnal wheezing following the onset of ULDP was believed for 15 years to have asthma. A patient with bilateral diaphragmatic weakness had severe choking sensation only in the supine position, simulating upper airway obstruction or heart failure. A female patient suffered nocturnal sweating due to ULDP. The clinical manifestations of diaphragmatic paralysis vary and can mimic a wide range of cardiorespiratory diseases.