Associations of tissue Doppler imaging with NT-proBNP and hs-TnT: a pilot study in end-stage renal disease.

BACKGROUND

Diastolic dysfunction is common and associated with higher mortality in the end-stage renal disease (ESRD) population. E/E', a measure derived from tissue Doppler imaging (TDI), is a correlate of left ventricular (LV) filling pressures. E/E' may be viewed as a confirmatory marker of diastolic dysfunction, but it is not routinely used to quantify diastolic dysfunction. Whether E/E' is associated with N-terminal brain natriuretic peptide (NT-proBNP) or high sensitivity troponin T (hs-TnT) in this population is not known.

METHODS

We performed echocardiograms and serology prior to the 2nd or 3rd dialysis session of the week on 35 chronic hemodialysis patients. We compared TDI parameters (E/E' and E' alone), traditional categories of diastolic function (normal, impaired, pseudonormal or restrictive), and ejection fraction (EF) as potential predictors of the outcomes NT-proBNP and hs-TnT.

RESULTS

Higher E/E' was associated with higher NT-proBNP (rho 0.48, P = 0.004) and hs-TnT (rho 0.37, P = 0.03). EF did not have statistically significant associations with NT-proBNP (rho -0.2, P = 0.4) or hs-TnT (rho -0.24, P = 0.16). As compared to patients with normal diastolic function, those with impaired or pseudonormal filling patterns did not have significantly different levels of NT-proBNP (P = 0.46); patients in traditional categories of worsened diastolic function actually had lower hs-TnT (P = 0.02). The associations of E/E' with higher NT-proBNP and hs-TnT persisted after multivariate adjustment for EF, LV mass, and volume status.

CONCLUSIONS

Tissue Doppler imaging may be more useful in evaluating cardiac function than traditional measures of diastolic dysfunction in the ESRD population.