This Article Full Text Full Text (PDF) All Versions of this Article: 113/2/252    most recent CIRCULATIONAHA.105.560649v1 Alert me when this article is cited Alert me if a correction is posted Citation Map Services Email this article to a friend Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Request Permissions Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Ciarka, A. Articles by van de Borne, P. Search for Related Content PubMed PubMed Citation Articles by Ciarka, A. Articles by van de Borne, P. Pubmed/NCBI databases Medline Plus Health Information Heart Transplantation Related Collections Other heart failure

(Circulation. 2006;113:252-257.)
© 2006 American Heart Association, Inc.

Heart Failure

Increased Peripheral Chemoreceptors Sensitivity and Exercise Ventilation in Heart Transplant Recipients

Agnieszka Ciarka, MD; Nicolas Cuylits, MD; Jean-Luc Vachiery, MD; Michel Lamotte, BSc; Jean-Paul Degaute, MD, PhD; Robert Naeije, MD, PhD; Philippe van de Borne, MD, PhD

From the Department of Cardiology, Erasme University Hospital (A.C., N.C., J.L.V., M.L., J.-P.D., P.v.d.B.), and Physiology Institute, Free University of Brussels (R.N.), Brussels, Belgium.

Correspondence to Agnieszka Ciarka, Department of Cardiology, Erasme Hospital, 808 Lennik Rd, 1070 Brussels, Belgium. E-mail Agnieszka.Ciarka{at}ulb.ac.be

Received May 6, 2005; revision received November 3, 2005; accepted November 7, 2005.

Background— Heart failure is characterized by increased ventilation during exercise, which is positively related to increased peripheral and central chemoreceptor sensitivity. Heart transplantation does not normalize the ventilatory response to exercise, and its effects on the chemoreflex control of ventilation remain unknown. We tested the hypothesis that chemoreceptor sensitivity is increased in heart transplant recipients (HTRs) and linked to exercise hyperpnea.

Methods and Results— We determined the ventilatory, muscle sympathetic nerve activity (MSNA), and circulatory responses to isocapnic hypoxia and hyperoxic hypercapnia 7±1 years after transplantation in 19 HTRs with a normal left ventricular ejection fraction of 60±2%. Results were compared with those of 11 closely matched referent subjects. Sixteen patients and 10 referent subjects also underwent cycle ergometer exercise tests. HTRs compared with referent subjects presented higher MSNA (52±4 versus 34±3 bursts/min; P<0.01) and heart rates (83±3 versus 68±3 bpm; P<0.01) during room air breathing. The ventilatory response to hypoxia was higher in HTRs than in referent subjects (P<0.01, ANOVA). The increase in MSNA also was more marked during hypoxia in the HTRs than in the referent group (P<0.05, ANOVA). Responses to hyperoxic hypercapnia did not differ between the HTRs and the referent group. The ventilatory response to exercise, characterized by the regression slope relating minute ventilation to CO₂ output, was steeper in HTRs than in referent subjects (38±2 versus 29±1 L/mm Hg; P<0.01). Exercise ventilation in HTRs was related to the ventilatory response to isocapnic hypoxia (r=0.57; n=16; P<0.05) and to the ventilatory response to hyperoxic hypercapnia (r=0.50; n=16; P<0.05).

Conclusions— Peripheral chemoreceptor sensitivity is increased in HTRs and is related to exercise hyperpnea after heart transplantation.

---

 

CLINICAL PERSPECTIVE

This article has been cited by other articles:

				A. Houssiere, M. Gujic, G. Deboeck, A. Ciarka, R. Naeije, and P. van de Borne Increased metaboreflex activity is related to exercise intolerance in heart transplant patients Am J Physiol Heart Circ Physiol, December 1, 2007; 293(6): H3699 - H3706. [Abstract] [Full Text] [PDF]