Author + information
- Olivier Ormezzano, MD, PhD∗ ( and )
- Jean-Philippe Baguet, MD, PhD
- ↵∗Clinic of Cardiology, Joseph Fourier University, University Hospital of Grenoble, 38043 Grenoble, France
We read with great interest the study by Zuern et al. (1) about the possibility of predicting for the first time the response to renal sympathetic denervation (RDN) in patients with resistant hypertension, using cardiac baroreflex sensitivity (BRS).
This fascinating report demonstrates that 1) the antihypertensive effect of RDN was greater in patients with impaired BRS, and 2) this effect was associated with restoration of BRS after the procedure. These positive results were obtained with BRS measured in 2 ways, namely, the classical sequence method (BRSseq) and the bivariate phase rectified signal averaging method (BRSprsa). In this study of 50 patients, analysis of receiver operating characteristic (ROC) curves showed that BRSprsa was a better predictor of the hypotensive effect of RDN than BRSseq. Consequently, the investigators focused the rest of the analysis on BRSprsa using a more complex and accurate predictive model. It would, nevertheless, be a pity at this stage of RDN development to ignore BRSseq, which is the only BRS measurement technique that benefits from prognostic data in patients with hypertension. The EVABAR (Evaluation of the Prognostic Value of Baroreflex Sensitivity in Hypertensive Patients) study, which investigated a cohort of 451 patients with hypertension with no particular history who were followed for an average of 6.2 years, demonstrated the prognostic role of BRSseq for cardiovascular events (2). Using a BRS measurement technique that benefits from prognostic data is all the more relevant because there does not currently exist any method of identifying those patients with hypertension whose prognosis might be improved by RDN (above and beyond lower blood pressure).
In addition, the accompanying editorial (2) emphasized the fact that BRS was not uniformly predictive for all patients with hypertension nor did it predict the magnitude of blood pressure reduction. The results of Zuern et al. (1) would suggest that the value of higher-resolution analysis of BRS was to determine whether the sympathetic component on its own or the sympathetic/parasympathetic balance would improve prediction of the efficacy of RDN on blood pressure. Distinguishing between BRSseq “up” and “down” sequences would make it easier to weigh the sympathetic and parasympathetic contributions (3,4).
- American College of Cardiology Foundation
- Zuern C.S.,
- Eick C.,
- Rizas K.D.,
- et al.
- Kandzari D.E.,
- Sobotka P.A.