QT INTERVAL CHANGES FOLLOWING NECK DISSECTION - A STRATIFIED PROSPECTIVE-STUDY

Studies from Europe have suggested that neck dissection, especially ri ght radical neck dissection, causes a dangerous prolongation of the QT interval. Sudden cardiac arrest due to QT prolongation has been repor ted following right radical neck dissection. We investigated the preva lence of QT interval prolongation following neck dissection. Electroca rdiogram tracings from 45 patients who underwent different combination s of neck dissection were studied. Preoperative and postoperative trac ings were interpreted by a cardiologist blinded to the patient identif ication of each tracing. There were 28 unilateral neck dissection pati ents and 17 bilateral neck dissection patients eligible for analysis. There were 7 patients in the classic right radical neck dissection gro up, and only 3 of these had no neck dissection on the left. Comparison s of preoperative versus postoperative corrected QT interval for all s ubjects did not indicate a significant change. Stratification by neck dissection type (radical, modified or selective, and carotid artery re section) or by side dissected (left, right, or both) also showed no si gnificant differences. No malignant arrhythmias were encountered. Thus , in contrast to the European experience, our findings show no signifi cant predictable change in the QT interval after any of the combinatio ns of neck dissection. Head and neck surgeons should be aware of the p ossibility of postoperative QT interval prolongation following neck di ssection, although in the absence of other risk factors it appears to be a rare occurrence.