QT dispersion in acute pulmonary embolism

Abstract

To explore the alteration and the clinical significance of QT dispersion in acute pulmonary embolism (PE). From May 2011 to April 2012, 42 hospitalized PE patients in Xiangya Hospital of Central South University were enrolled, and divided into a high-risk group and a non-high-risk group according to the clinic state on admission. Another 30 healthy subjects with matched age and genders were enrolled as a normal control group. QT interval was measured manually in 12- lead conventional electrocardiogram within 24 hours on admission and after the treatment. QT dispersion (QTd) and heart rate-corrected QT dispersion (QTcd) were also calculated. All patients were followed up during hospitalization, and were divided to a death group and a survival group. QTd and QTcd in the high-risk group [(70.2±34.0), (88.1±43.3) ms] and the non-high-risk group [(49.3±21.8), (59.1±26.2) ms] were significantly higher than those in the normal control group[(33.2±12.4), (36.7±14.2) ms] (P<0.05), while QTd and QTcd in the high-risk group were significantly higher than those in the non-high-risk group (P<0.05). The interval of electrocardiogram was (5.6±2.5) days between 24 hours on admission and after the treatment (ECG). QTd and QTcd were reduced significantly after the treatment in the survival group [(41.0±16.4), (47.4±18.0)ms] compared with those on admission [(54.0±33.0), (67.2±40.5)ms] (P<0.05), but the QTd and QTcd after the treatment were also significantly higher than those in the normal control group (P<0.05). There was no significant difference in the QTd and QTcd between 24 hours on admission and after the treatment in the death group (P>0.05). Logistic regression showed that high-risk of PE, right ventricular dysfunction and high QTcd after the treatment were the main risk factors of hospital death. QTd and QTcd are increased in PE. PE patients with right ventricular dysfunction, high-risk of PE, and high QTcd after the treatment suggest weak prognosis.