HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:
Guest Access | Sign In via User Name/Password

This Article Full Text (PDF) Free All Versions of this Article: chest.06-2690v1 132/1/37    most recent Submit a response Alert me when this article is cited Alert me when eLetters are posted Alert me if a correction is posted Services Email this article to a friend Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Add to My Personal Article Archive Download to citation manager Citing Articles Citing Articles via Google Scholar Google Scholar Articles by Karamanoglu, M. Articles by Bennett, T. D Search for Related Content PubMed PubMed Citation Articles by Karamanoglu, M. Articles by Bennett, T. D

Right Ventricular Pressure Waveform and Wave Reflection Analysis in Patients with Pulmonary Arterial Hypertension

Mustafa Karamanoglu, PhD^*; Michael McGoon, MD; Robert P. Frantz, MD; Raymond L. Benza, MD; Robert C. Bourge, MD; Robyn J. Barst, MD; Barbro Kjellström, BS^* and Tom D Bennett, PhD^*

^*NT&D Research, Medtronic Inc, Minneapolis, Minnesota, USA Division of Cardiovascular Diseases, Department of Internal Medicine, Mayo Clinic College of Medicine, Rochester, Minnesota, USA Department of Medicine, University of Alabama at Birmingham, Birmingham, Alabama, USA Department of Pediatrics, Columbia University College of Physicians & Surgeons, New York, New York, USA

mustafa.karamanoglu{at}Medtronic.com

Abstract

BackgroundCardiac index is an important determinant of outcome in idiopathic pulmonary artery hypertension (IPAH). An implantable hemodynamic monitor (Chronicle^®*, Medtronic, Inc.) that records right ventricular pressure waveforms continuously may increase our understanding of IPAH and improve therapeutic selections and outcomes. The aim of this study was to investigate whether the right ventricular pressure waveform utilizing an implantable hemodynamic monitor can be used to estimate the magnitude of pressure wave reflection and cardiac index in patients with IPAH in acute settings.

MethodsIn 8 patients with PAH, right ventricular pressure waveforms were recorded utilizing the implantable monitor, and breath-by-breath cardiac index was recorded during acute IV epoprostenol infusion at 3, 6 and 9 ng/Kg/min. The late systolic pressure augmentation and the cardiac index were estimated using the right ventricular pressure waveforms and correlated with direct measurement of cardiac index.

ResultsAt baseline the cardiac index was 2.1±0.2 L/min/m², total pulmonary resistance index 38±2 Wood's Units·m² and right ventricular systolic pressure 92±4 mmHg. Wave reflection accounted for 29±1 mmHg of the right ventricular systolic pressure. During epoprostenol infusion, the total pulmonary resistance index and wave reflection decreased (-15±4 Wood's Units·m², p<0.001 and -5±2 mmHg, p<0.05, respectively). The breath-by-breath cardiac index correlated with the right ventricular pressure waveform cardiac index estimates (r²=0.95).

ConclusionsRight ventricular pressure waveform analysis provides continuous hemodynamic assessments, including cardiac index in acute settings. Once confirmed in chronic settings this information may prove useful in optimizing treatment regimen in patients with IPAH.

Key Words: Pulmonary Arterial Hypertension • Right Ventricular Pressure • Wave Reflection • Cardiac Output • Epoprostenol