Buppajarntham Saranya, Seetha Rammohan Harish Raj, Junpaparp Parichart, Figueredo Vincent M
Acta Cardiol. 2014 Oct;69(5):550-5. doi: 10.1080/ac.69.5.3044882.
BACKGROUND/OBJECTIVES: Acute pulmonary embolism (PE) can be a life-threatening condition. Right ventricular function evaluated by echocardiography, brain natriuretic peptide levels and several patterns on the electrocardiogram have been utilized to guide treatment and prognosis. Case reports described heart rate corrected QT (QTc) prolongation as an ECG finding associated with PE. However, the prognostic value of QTc prolongation has not been studied.
Retrospective chart review of 300 consecutive patients (mean age 60.3 ± 17.6 years; 40.7% men) diagnosed with acute PE by computed tomography pulmonary angiography or ventilation perfusion scan were studied. Patients were divided into two groups: a prolonged QTc group with QTc >460 milliseconds (n=178) and a control group (n=122). We retrospectively reviewed medical records, electrocardiography, echocardiography and radiography results. Statistical analyses included unpaired t-test and Fisher's exact test using Stata version12.
The prolonged QTc group demonstrated significantly increased right ventricular dilatation and systolic dysfunction. Additionally, the duration of hospitalization and intensive care unit stay were longer in the prolonged QTc group. Further, the prolonged QTc group had more hypotensive episodes and received thrombolytic treatment more frequently. There was no statistical difference in in-patient mortality rates (4.5% for the study group and 4.2% for the control group, P=1).
Prolonged QTc may prove a novel predictor for evaluating prognosis in acute PE. Larger studies will need to confirm this finding.
背景/目的：急性肺栓塞（PE）可能是一种危及生命的疾病。通过超声心动图评估的右心室功能、脑钠肽水平以及心电图上的几种模式已被用于指导治疗和判断预后。病例报告描述心率校正QT（QTc）延长是与PE相关的一种心电图表现。然而，QTc延长的预后价值尚未得到研究。
对300例连续诊断为急性PE的患者（平均年龄60.3±17.6岁；男性占40.7%）进行回顾性病历审查，这些患者通过计算机断层扫描肺动脉造影或通气灌注扫描确诊。患者分为两组：QTc>460毫秒的QTc延长组（n = 178）和对照组（n = 122）。我们回顾性审查了病历、心电图、超声心动图和影像学检查结果。统计分析采用Stata 12版软件进行不成对t检验和Fisher精确检验。
QTc延长组显示右心室扩张和收缩功能障碍显著增加。此外，QTc延长组的住院时间和重症监护病房停留时间更长。此外，QTc延长组有更多的低血压发作，且更频繁地接受溶栓治疗。住院死亡率无统计学差异（研究组为4.5%，对照组为4.2%，P = 1）。
QTc延长可能是评估急性PE预后的一个新的预测指标。需要更大规模的研究来证实这一发现。
