Respiratory failure and pulmonary hypertension associated with Klippel-Feil syndrome.

A 28-year-old woman with a deformed thorax and kyphoscoliosis associated with Klippel-Feil syndrome developed respiratory failure with pulmonary hypertension. Pulmonary 133Xe ventilation and 99mTc-MAA perfusion scintigraphies showed maldistributions of lung ventilation and perfusion, and noticeably delayed 133Xe washout from the lungs. Dynamic breathing MR imaging showed poor and/or asynchronous respiratory movements of the chest wall and diaphragm. These findings indicate that the perfusion-ventilation imbalance, the decreased ventilatory turnover, and expiratory flow from the alveolar space partly derived from the impaired respiratory mechanics may be responsible for the respiratory complications in this patient.