Analysis of heart rate turbulence in advanced heart failure and heart transplantation patients

The objective of this study was to describe heart rate turbulence (HRT) in advanced heart failure (HF) patients and in a group of patients who underwent heart transplantation (HT).

We performed 24-hour Holter recordings in 20 patients with advanced HF referred to our hospital for HT, including 16 males of overall mean age of 44 +/- 13 years and with a mean ejection fraction (EF) 21 +/- 7%. An additional set of recordings was obtained in a second group of 27 patients who had already undergone HT, including of 21 males of overall mean age of 47 +/- 14 years. We recorded the number of premature ventricular contractions (PVCs), mean heart rate (MHR), and 2 parameters of HRT-turbulence onset (TO) and turbulence slope (TS).

Patients with HT showed a low density of premature ventricular complexes, in contrast to patients in the advanced HF group. For this reason, HRT could only be analyzed in 15 of the patients with advanced HF (66%) and in 10 of the patients who underwent HT (37%). MHR was 77 +/- 10 bpm in the advanced HF group and 90 +/- 10 bpm in the HT group. In both groups, TO and TS showed highly attenuated values.

Patients with advanced HF showed a high number of PVCs with attenuated HRT parameters, reflecting increased circulating catecholamine levels and decreased response of the autonomic nervous system. Patients who underwent HT showed elevated MHRs, a small number of PVCs, and attenuated HRT values, as corresponds to a denervated heart.