左间隔支阻滞与QRS时限诊断左室舒张性心力衰竭的临床价值

The value of the left fascicular block and QRS duration for the diagnosis of left ventricular diastolic heart failure

目的观察左间隔支阻滞和常规心电图QRS时限评估充血性心力衰竭患者舒张功能的价值。方法75例符合NYHAⅡ-Ⅳ级充血性心力衰竭(CHF)患者为观察对象(男39例,女36例,平均年龄69.3±13.4岁)。采用多普勒-超声心动图(Doppler-Echo)为诊断标准,以左室射血分数(LVEF)≥50%及<50%分为左室舒张性心力衰竭(DHF)和收缩性心力衰竭(SHF)两组。分别评价QRS时限,左间隔支阻滞以及将两项指标合并后在诊断DHF时的敏感性和特异性。结果DHF组QRS时限(n=31,QRS=92±23ms)显著短于SHF组(n=44,QRS=124±27ms,p<0.01)。作为DHF的预测指标,尽管QRS时限≤100ms特异性高(95.45%),但敏感性较差(61.29%);而QRS时限≤120ms敏感性显著高于100ms(87.10%,与61.29%),其特异性显著高于QRS时限≤140ms(81.82%与43.18%);同样,左间隔支阻滞敏感性高而特异性较差(分别为90.32%及61.36%)。将QRS时限≤120ms与左间隔支阻滞两项指标作为联量检测标准,尽管敏感性下降(87.10%,90.32%与83.87%),但特异性则有显著性提高(81.82%,61.36%与86.36%,p<0.01)。结论鉴于QRS时限≤120ms与左间隔支阻滞联合诊断标准的特异性高于各单项指标,故可用于左室舒张性心衰的临床诊断。

Objective To investigate the value of the presence of the left septal fascicular block （LSFB） and the QRS duration on a standard ECG in assessing left ventricular diastolic function in patients with congestive heart failure（CHF）. Methods 75 patients （39 men and 36 women, mean age 69.3±13.4 years） with CHF satisfying NYHA class Ⅱ-Ⅳwere examined. Using the Doppler-Echocardiogram （Doppler-Echo）as a standard, all of the patients were divided into diastolic heart failure （DHF） with the LVEF≥50% and systolic heart failure （SHF） with the LVEF;〈50% respectively. A QRS （ms） cut-off value of detecting DHF was defined. The sensitivity and the specificity of QRS duration, LSFB and the combination of both criteria in the diagnoses of DHF were tested respectively. Results The QRS duration in the DHF group was shorter than in the SHF group （p〈0.01）. For the prediction of DHF, the QRS duration of 〈100ms was less sensitive （61.29%） though it was highly specific （95.45%）; whereas the QRS duration≤120ms was more sensitive than ≤100ms （87.10%, vs. 61.29%） and more specific than QRS duration ≤ 140ms （81.82% vs. 43.18%）; the LSFB was also highly sensitive （90.32%） but less specific （61.36%）. The specificity for DHF of QRS duration≤120ms and the presence of LSFB was improved by the combination of both criteria, though the sensitivity was decreased. Conclusion The combination of QRS duration≤ 120ms and the presence of LSFB yields a higher specificity compared with the two criteria alone and can be used to estimate DHF.