QT interval prolongation by acute gastrointestinal bleeding in patients with cirrhosis

摘要

Background & aims: QT interval prolongation is frequent in cirrhosis, and stressful conditions could further prolong QT. We aimed to test this hypothesis and, if it proved correct, to assess its prognostic meaning. Methods: We reviewed the clinical records of 70 consecutive cirrhotic and 40 non-cirrhotic patients with acute gastrointestinal bleeding. All patients had been evaluated before bleeding (T0) and were re-evaluated at the time of bleeding (T1) and 6 weeks afterwards (T2). Results: QT corrected by heart rate (QTc) lengthened at T1, returning towards baseline values at T2 (mean ± SEM; from 415.9 ± 4.3 to 453.4 ± 4.3 to 422.2 ± 5.7 ms, P < 0.001) in cirrhotics; contrariwise, QTc did not change in non-cirrhotic patients. The 6-week mortality was 29.6% among cirrhotic patients, while no control patient died. At T1, patients who died had longer QTc (P = 0.001) and higher model of end-stage liver disease (MELD) score (P < 0.001) than survivors. MELD and QTc independently predicted survival. Their areas under the ROC curve were 0.88 (CI 95% 0.78-0.95) and 0.75 (CI 95% 0.63-0.85) respectively; the best cut-off values were MELD ≥20 and QTc ≥ 460 ms. Based on these factors, the 6-week mortality was: 0% for patients without risk factors, 32.1% for those with one risk factor and 70.6% for those with both (P < 0.001). Conclusions: Acute gastrointestinal bleeding further prolongs QTc in cirrhosis. This abnormality independently predicts bleeding-induced mortality. The combined measurement of QTc interval and MELD can clearly identify three patient strata at increasing risk of bleeding-related mortality, thus improving the decision-making for these patients.