HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Full Text Full Text (PDF) All Versions of this Article: 105/6/1916    most recent 90572.2008v1 Submit a response Alert me when this article is cited Alert me when eLetters are posted 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 Citing Articles Citing Articles via Google Scholar Google Scholar Articles by Tanné, D. Articles by Pibarot, P. Search for Related Content PubMed PubMed Citation Articles by Tanné, D. Articles by Pibarot, P.

Hemodynamic impact of mitral prosthesis-patient mismatch on pulmonary hypertension: an in silico study

¹Quebec Heart Institute/Laval Hospital, Laval University, Sainte-Foy, Québec, ³Department of Mechanical and Industrial Engineering, Concordia University, Montreal, Quebec, Canada; and ²Cardiovascular Biomechanics Team, Institut de Recherche sur les Phénomènes Equilibre, Centre National de Recherche Scientifique, Université de la Méditerranée, Marseille, France

Submitted 25 April 2008 ; accepted in final form 18 August 2008

Recent clinical studies reported that prosthesis-patient mismatch (PPM) becomes clinically relevant when the effective orifice area (EOA) indexed by the body surface area (iEOA) is <1.2–1.25 cm²/m². To examine the effect of PPM on transmitral pressure gradient and left atrial (LA) and pulmonary arterial (PA) pressures and to validate the PPM cutoff values, we used a lumped model to compute instantaneous pressures, volumes, and flows into the left-sided heart and the pulmonary and systemic circulations. We simulated hemodynamic conditions at low cardiac output, at rest, and at three levels of exercise. The iEOA was varied from 0.44 to 1.67 cm²/m². We normalized the mean pressure gradient by the square of mean mitral flow indexed by the body surface area to determine at which cutoff values of iEOA the impact of PPM becomes hemodynamically significant. In vivo data were used to validate the numerical study, which shows that small values of iEOA (severe PPM) induce high PA pressure (residual PA hypertension) and contribute to its nonnormalization following a valve replacement, providing a justification for implementation of operative strategies to prevent PPM. Furthermore, we emphasize the major impact of pulmonary resistance and compliance on PA pressure. The model suggests also that the cutoff iEOA that should be used to define PPM at rest in the mitral position is 1.16 cm²/m². At higher levels of exercise, the threshold for iEOA is rather close to 1.5 cm²/m². Severe PPM should be considered when iEOA is <0.94 cm²/m² at rest.

heart valve; mitral flow; lumped model; pulmonary resistance; effective orifice area