Mexiletine for the treatment of ventricular arrhythmias associated with chronic obstructive pulmonary disease.
Ventricular arrhythmias complicating chronic obstructive pulmonary disease, when refractory to the correction of acidosis and hypoxia, may lead to a poor prognosis. Mexiletine efficacy was assessed in 14 patients (pts.) with chronic obstructive pulmonary disease and premature ventricular contractions; they entered a cross-over trial consisting of 7-day therapy with oral placebo and mexiletine (200 mg q.i.d.). The hourly means of premature ventricular contractions, their hourly peaks and the severity scores of arrhythmias were compared. The analysis of linear regression showed a slight spontaneous variability of premature ventricular contractions in the study group. Unexpectedly, the highly homogeneous data raised the question if this method of evaluation for anti-arrhythmic therapy reaches a satisfactory conclusion. Nevertheless, treatment with mexiletine significantly reduced the premature ventricular contractions count and their hourly peak (p less than 0.001) as well as their severity score (p less than 0.001). Analysis of linear regression and confidence intervals confirmed the efficacy of the drug. According to the statistical method used, antiarrhythmic therapy with mexiletine generally achieved its purpose in pts. with chronic obstructive pulmonary disease.