I导联宽“M”型QRS波与左室功能的关系

The analysis of left ventricular systolic function in patients with ECG broad "M" shape on lead Ⅰ

目的探讨完全性左束支阻滞(CLBBB)患者心电图I导联QRS波呈宽"M"型在评估左室功能及临床危险程度方面的作用。方法心电图检出CLBBB患者I导联QRS波呈宽"M"型20例为"M"型组,随机选择41例I导联无"M"型的CLBBB患者作为对照组,经心脏超声检测左室舒张期末内径、左室收缩期末内径、左室射血分数、左室心肌节段性运动,对照分析左室功能状况。结果①"M"型组100%出现左室扩大,其中8例全心扩大,对照组左室扩大11例占26.83%;②"M"型组19例(19/20)患者出现左室室壁整体运动减低,占95%,对照组7例,如果包括局部运动减低共18例(18/41),占43.90%;③"M"型组20例患者的射血分数均低于40%,对照组仅5例;④"M"型组20例患者左室收缩期末内径均>37mm,对照组12例;⑤"M"型组20例患者的左室舒张期末内径均>56mm,对照组11例。两组间各种指数对照结果x2检验,差异显著(p<0.05)。结论发生在慢性心力衰竭并CLBBB患者的心电图I导联QRS波呈宽"M"型与患者左室扩大、左室泵功能明显降低密切相关;如果CLBBB患者出现I导联QRS波呈宽"M"型,提示其心衰严重,危险程度增加,预后较差。

Objective To assess the value of broad ＂M＂shape on lead I in patients with left bundle branch block（LBBB） to evaluate the cardiac function and risk stratification. Methods Twenty patients with and 41 cases without broad＂M＂shape on lead Ⅰ were selected（as Group of broad＂M＂shape for the patients with broad＂M＂ shape on lead Ⅰ and Group of control as the patients without broad M shape on lead Ⅰ） . The ECG results was compared with both systolic and diastolic dimension of left ventricle（LVDd,LVDs） ,ejection fraction（EF） and segmental motion of left ventricle were evaluated by echocardiography. Results Left ventricular enlargement was 100% in the Group of broad＂M＂shape（8 cases of enlargement of whole heart） ,compared with 26.83%（11 cases） of left ventricular enlargement in Group of Control. Abnormal wall motion in all left ventricular segments was seen in 95% patients（19 cases） in the Group of broad M shape and only 43.90%（18 cases） in the Control. EF〈 40% was found in all patients of Group of broad M shape and only 5 cases in the Control. Twenty patients with LVDd〉56 mm and LVDs〉37mm were observed in Group of broad M shape compared with those only in 12 cases with LVDd〉56 mm and 11 cases with LVDs〉37mm in the Control,which showed significant difference by x2 test between the groups statistically（p〈0.05） . Conclusions It seems that broad＂M＂shape on lead I of ECG with complete left bundle branch block（CLBBB） is related closely with enlargement of left ventricle and decrease of pump function of the left ventricle,which might be an indication for sever heart failure and poor prognosis.