Fitting J W, Leuenberger P
Département de Médecine Interne, Centre Hospitalier Universitaire Vaudois, Lausanne, Switzerland.
Am Rev Respir Dis. 1989 Nov;140(5):1442-5. doi: 10.1164/ajrccm/140.5.1442.
We report the case of a patient with myotonic dystrophy who developed tachypnea and severe dyspnea without respiratory failure. Myotonia of inspiratory muscles was diagnosed on the grounds of marked prolongation of transdiaphragmatic pressure (Pdi) decay during sniffs. In view of the recognized sensory role of inspiratory muscles in dyspnea, it was hypothesized that antimyotonic therapy might relieve dyspnea in this patient. Procainamide therapy induced a decrease in half relaxation time of Pdi during sniffs and yielded a striking clinical improvement with cessation of tachypnea and dyspnea. Later, this beneficial effect was maintained by tocainide after procainamide was stopped because of a lupus syndrome. We conclude that myotonia of respiratory muscles can cause severe dyspnea that can be improved by antimyotonic therapy.
我们报告了一例患有强直性肌营养不良的患者，该患者出现呼吸急促和严重呼吸困难，但无呼吸衰竭。基于吸气时经膈压（Pdi）衰减明显延长，诊断为吸气肌强直性肌病。鉴于吸气肌在呼吸困难中已被认可的感觉作用，推测抗强直性肌病治疗可能缓解该患者的呼吸困难。普鲁卡因胺治疗使吸气时Pdi的半松弛时间缩短，并使呼吸急促和呼吸困难停止，临床症状显著改善。后来，由于狼疮综合征停用普鲁卡因胺后，妥卡尼维持了这种有益效果。我们得出结论，呼吸肌强直性肌病可导致严重呼吸困难，抗强直性肌病治疗可改善这种情况。
