Advertisement





Click here for more guidelines.
CME Topic Collections Past Issues Search Current Issue Home
     

J Am Coll Cardiol, 2008; 52:108-113, doi:10.1016/j.jacc.2007.12.063
© 2008 by the American College of Cardiology Foundation
This Article
Right arrow Figures Only
Right arrow Full Text
Right arrow Full Text (PDF)
Right arrow Alert me when this article is cited
Right arrow Alert me if a correction is posted
Services
Right arrow Email this article to a friend
Right arrow Similar articles in this journal
Right arrow Alert me to new issues of the journal
Right arrow Download to citation manager
Citing Articles
Right arrow Citing Articles via HighWire
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by Meadows, J.
Right arrow Articles by Rhodes, J.
Right arrow Search for Related Content
PubMed
Right arrow Articles by Meadows, J.
Right arrow Articles by Rhodes, J.
Related Collections
Right arrowRelated Article

MINI-FOCUS ISSUE: THE FONTAN PROCEDURE

Fontan Fenestration Closure Has No Acute Effect on Exercise Capacity but Improves Ventilatory Response to Exercise

Jeffery Meadows, MD*,*, Peter Lang, MD*,{dagger}, Gerald Marx, MD*,{dagger} and Jonathan Rhodes, MD*,{dagger}

* Department of Cardiology, Children's Hospital–Boston, Boston, Massachusetts
{dagger} Department of Pediatrics, Harvard Medical School, Boston, Massachusetts.

Manuscript received October 1, 2007; revised manuscript received December 12, 2007, accepted December 18, 2007.

* Reprint requests and correspondence: Dr. Jeffery J. Meadows, University of California at San Francisco, Department of Pediatric Cardiology, Box 0632, 505 Parnassus Avenue, San Francisco, California 94143. (Email: Jeffery.meadows{at}ucsf.edu).

Objectives: The aim of this study was to prospectively examine the effects of elective Fontan fenestration closure upon exercise capacity and ventilatory abnormalities.

Background: For patients undergoing Fontan procedures as palliation of single ventricle physiology, the addition of a fenestration to the procedure mitigates perioperative morbidity. Although some fenestrations may close spontaneously, many remain patent and subject patients to arterial hypoxemia and risk for paradoxical emboli. For these reasons fenestration closure is routinely performed post-operatively in the cardiac catheterization laboratory. Although closure of Fontan fenestrations typically results in an immediate improvement in systemic arterial oxygen saturation, it is also associated with an acute decrease in cardiac index and systemic O2 delivery. The sum result of these physiologic changes upon exercise capacity has not been examined.

Methods: Twenty consecutive patients, age 5 to 46 (median 10) years, underwent pre- and post-fenestration closure exercise testing with expiratory gas analysis.

Results: Before fenestration closure, peak oxygen consumption (VO2) was depressed and there was systemic desaturation at rest that worsened with exercise. The ventilatory response to exercise was also abnormal, characterized by elevation of the minute ventilation (VE)/CO2 elimination slope (VE/VCO2), a low end-tidal CO2, and high end-tidal O2 at the ventilatory anaerobic threshold. Although arterial saturation improved significantly after fenestration closure, there was no change in peak VO2 (70.9 ± 18.6% to 74.0 ± 18.6%, p = NS), heart rate, or O2 pulse at peak exercise. In contrast, ventilatory abnormalities (VE/VCO2) improved considerably (44.4 ± 10.9 to 33.3 ± 5.5, p ≤ 0.001).

Conclusions: Fontan fenestration closure does not significantly improve peak VO2. However, ventilatory abnormalities improve considerably.

Key Words: congenital heart disease • exercise testing • fenestrated Fontan

Abbreviations and Acronyms
  pCO2 = partial pressure of carbon dioxide
  pETCO2 = partial pressure of end-tidal carbon dioxide
  pETO2 = partial pressure of end-tidal oxygen
  pO2 = partial pressure of oxygen
  QpQs = ratio of pulmonary to systemic blood flow
  RER = respiratory exchange ratio
  VAT = ventilatory anaerobic threshold
  VE = minute ventilation
  VE/VCO2 = minute ventilation/carbon dioxide elimination
  VO2 = oxygen consumption


Related Article

The Fontan Procedure: Our Odyssey Continues
Carl Lewis Backer
J. Am. Coll. Cardiol. 2008 52: 114-116. [Full Text] [PDF]



This article has been cited by other articles:


Home page
J Am Coll CardiolHome page
A. N. DeMaria, O. Ben-Yehuda, J. J. Bax, G. K. Feld, B. H. Greenberg, W. Y.W. Lew, J. A.C. Lima, A. S. Maisel, S. M. Narayan, D. J. Sahn, et al.
Highlights of the Year in JACC 2008.
J. Am. Coll. Cardiol., January 27, 2009; 53(4): 373 - 398.
[Full Text] [PDF]


Home page
J Am Coll CardiolHome page
C. L. Backer
The Fontan Procedure: Our Odyssey Continues
J. Am. Coll. Cardiol., July 8, 2008; 52(2): 114 - 116.
[Full Text] [PDF]



 
  CME Topic Collections Past Issues Search Current Issue Home

Advertisement