QT dispersion is not associated with sudden cardiac death or mortality in heart transplant recipients

Heart Surg Forum. 2008;11(5):E281-4. doi: 10.1532/HSF98.20081023.

Abstract

Background: Sudden cardiac death (SCD) has been shown to be a significant cause of death after heart transplantation. QT dispersion (QTd) is associated with SCD in several high-risk populations. We hypothesized that QTd would predict mortality and SCD in heart transplantation patients.

Methods: We examined the clinical charts and most recent electrocardiograms (ECGs) for patients who received heart transplants at Stanford University Medical Center during the period 1981-1995. QTd was measured with all 12 leads and the precordial leads. Analysis was performed by a single reader blinded to patient outcomes.

Results: A total of 346 patients who had undergone transplantation had available ECGs and known outcomes; 155 of these patients died, and 42 of these deaths were attributed to SCD. The 12-lead mean QTd was not significantly different between outcome groups: patients who survived had a 12-lead mean QTd of 58 +/- 29 milliseconds and those who died had a 12-lead mean QTd of 61 +/- 32 milliseconds (P = .57). Patients who died from SCD had a 12-lead mean QTd of 57 +/- 31 milliseconds (P = .40), and those who died of other causes had a 12-lead mean QTd of 59 +/- 34 milliseconds (P = .36 vs those who died of SCD). Similarly, the precordial-lead mean QTd did not differ significantly between the different outcome groups.

Conclusions: We found no correlation between QTd and SCD or mortality in heart transplant recipients. Until additional studies prove a positive association, QTd should not be used as a prognostic marker in these patients.

MeSH terms

  • Arrhythmias, Cardiac / diagnosis*
  • Arrhythmias, Cardiac / mortality*
  • California / epidemiology
  • Death, Sudden, Cardiac / epidemiology*
  • Electrocardiography / methods
  • Electrocardiography / statistics & numerical data*
  • Female
  • Heart Transplantation / mortality*
  • Humans
  • Incidence
  • Male
  • Middle Aged
  • Reproducibility of Results
  • Retrospective Studies
  • Risk Assessment / methods*
  • Risk Factors
  • Sensitivity and Specificity
  • Survival Analysis
  • Survival Rate