慢性房性心动过速

CHRONIC ATRIAL TACHYCARDIA

本文报道7例不寻常的室上性心动过速,根据其发作过程可称为慢性房性心动过速。临床特点为心动过速长期存在;除心悸、胸闷外,大多无严重症状,2例心脏扩大和心力衰竭;经随访3月至7年(平均2年),仅2例转为窦性心律,余5例仍持续有房性心动过速,但病情稳定.根据心电图表现,6例属持久性房性心动过速,1例为反复性房性心动过速。房速通常伴有房室传导阻滞,呈Ⅰ度文氏型或Ⅰ度阻滞。慢性房速对各种治疗均无满意疗效,洋地黄可使房室传导阻滞增加和心房率减慢,因而可使心室率减慢和症状减轻,如与β阻滞剂合用,可以更好地控制心率。慢性房速病因不明,但大多数病人预后较好。

Six sustained and 1 repetitive cases of chronic atrial tachycardia are reported,with arrythmia lasted from 3 months to 20 years.The main clinical features were:chronicity throughout the years,resistance to conventional antiarrythmic therapy andrelatively good prognosis.The characteristic ECG features were variation in rate ofectopic atrial focus,a relatively slow rate with an average of 149 beats/min,associa-tion with A-V block and susceptibility to extracardiac physiologic influence.Thc elec-tric axis of the ectopic P wave in the frontal plane was directed superiorly in 3 pa-tients,inferiorly in 3 and diphasic in 1.In the sustained form,the tachycardia lastedfor months or years without sinus activity.In the repetitive variety,short runs oftachycardia were present for years and interspersed by 1,occasionally 2 or 3,sinusbeats.Digitalis treatment slowed down the ventricular rate in all patients by reducingthe ectopic rate and/or by increasing the degree of A-V block.