Korhonen Petri, Husa Terhi, Konttila Teijo, Tierala Ilkka, Mäkijärvi Markku, Väänänen Heikki, Ojanen Janne, Vehtari Aki, Toivonen Lauri
Helsinki University Hospital, Finland.
Ann Noninvasive Electrocardiol. 2010 Apr;15(2):130-7. doi: 10.1111/j.1542-474X.2010.00353.x.
Increased QRS fragmentation in visual inspection of 12-lead ECG has shown association with cardiac events in postmyocardial infarction (MI) patients. We investigated user-independent computerized intra-QRS fragmentation analysis in prediction of cardiac deaths and heart failure (HF) hospitalizations after MI.
Patients (n = 158) with recent MI and reduced left ventricular ejection fraction (LVEF) were studied. A 120-lead body surface potential mapping was performed at hospital discharge. Intra-QRS fragmentation was computed as the number of extrema (fragmentation index FI) in QRS. QRS duration (QRSd) was computed for comparison.
During a mean follow-up of 50 months 15 patients suffered cardiac death and 23 were hospitalized for HF. Using the mean + 1 SD as cut-point both parameters were univariate predictors of both end-points. In multivariate analysis including age, gender, LVEF, previous MI, bundle branch block, atrial fibrillation, and diabetes FI was an independent predictor for cardiac deaths (HR 8.7, CI 3.0-25.6) and HF hospitalizations (HR 3.8, CI 1.6-9.3) whereas QRSd only predicted HF hospitalizations (HR 4.6, CI 2.0-10.7). In comparison to QRSd, FI showed better positive (PPA) and equal negative (NPA) predictive accuracy for both end-points, and PPA was further improved when combined to LVEF < 40%. Limiting fragmentation analysis to 12-lead ECG or a randomly selected 8-lead set instead of all 120 leads resulted in an almost similar prediction.
Increased QRS fragmentation in post-MI patients predicts cardiac deaths and HF progression. A computer-based fragmentation analysis is a stronger predictor than QRSd.
在12导联心电图的视觉检查中，QRS波群碎裂增加已显示与心肌梗死后（MI）患者的心脏事件相关。我们研究了独立于用户的计算机化QRS波群内碎裂分析对心肌梗死后心脏死亡和心力衰竭（HF）住院的预测作用。
研究了近期发生心肌梗死且左心室射血分数（LVEF）降低的患者（n = 158）。出院时进行了120导联体表电位标测。QRS波群内碎裂计算为QRS波群中的极值数量（碎裂指数FI）。计算QRS时限（QRSd）用于比较。
在平均50个月的随访期间，15例患者发生心脏死亡，23例因心力衰竭住院。以平均值 + 1标准差作为切点，两个参数都是两个终点的单变量预测因子。在包括年龄、性别、LVEF、既往心肌梗死、束支传导阻滞、心房颤动和糖尿病的多变量分析中，FI是心脏死亡（HR 8.7，CI 3.0 - 25.6）和心力衰竭住院（HR 3.8，CI 1.6 - 9.3）的独立预测因子，而QRSd仅预测心力衰竭住院（HR 4.6，CI 2.0 - 10.7）。与QRSd相比，FI对两个终点均显示出更好的阳性预测准确性（PPA）和相同的阴性预测准确性（NPA），当与LVEF < 40% 联合时PPA进一步提高。将碎裂分析限于12导联心电图或随机选择的8导联组而非所有120导联，结果预测几乎相似。
心肌梗死后患者QRS波群碎裂增加可预测心脏死亡和心力衰竭进展。基于计算机的碎裂分析比QRSd是更强的预测因子。
