Relation between VE/VCO2 slope and maximum phonation time in chronic heart failure patients

This study aimed to determine the relation between the regression slope relating minute ventilation to carbon dioxide output (VE/VCO2 slope) and maximum phonation time (MPT), and the MPT required to attain a threshold value for VE/VCO2 slope of ≤ 34 in chronic heart failure (CHF) patients. This cros...

Full description

Saved in:
Bibliographic Details
Published in:Medicine (Baltimore) 2014-12, Vol.93 (29), p.e306-e306
Main Authors: Izawa, Kazuhiro P, Watanabe, Satoshi, Brubaker, Peter H, Tochimoto, Shinobu, Hirano, Yasuyuki, Matsushima, Shinya, Suzuki, Tomohiro, Oka, Koichiro, Saito, Takashi, Omori, Yutaka, Suzuki, Kengo, Osada, Naohiko, Omiya, Kazuto, Shimizu, Hiroyuki, Akashi, Yoshihiro J
Format: Article
Language:English
Subjects:
Cross-Sectional Studies
Exercise Tolerance - physiology
Female
Heart Failure - physiopathology
Humans
Male
Middle Aged
Phonation - physiology
Pulmonary Gas Exchange - physiology
Pulmonary Ventilation - physiology
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:This study aimed to determine the relation between the regression slope relating minute ventilation to carbon dioxide output (VE/VCO2 slope) and maximum phonation time (MPT), and the MPT required to attain a threshold value for VE/VCO2 slope of ≤ 34 in chronic heart failure (CHF) patients. This cross-sectional study enrolled 115 CHF patients (mean age, 54.5 years; men, 84.9%). VE/VCO2 slope was assessed during cardiopulmonary exercise testing (CPX). Thereafter, patients were divided into 2 groups according to exercise capacity: VE/VCO2 slope ≤ 34 (VE/VCO2 ≤ 34 group, n = 81) and VE/VCO2 slope > 34 (VE/VCO2 > 34 group, n = 34). For MPT measurements, all patients produced a sustained vowel/a:/ for as long as possible during respiratory effort from the seated position. All subjects showed significant negative correlation between VE/VCO2 slope and MPT (r = -0.51, P < 0.001). After adjustment for clinical characteristics, MPT was significantly higher in the VE/VCO2 ≤ 34 group vs VE/VCO2 > 34 group (21.4 ± 6.4 vs 17.4 ± 4.3 s, F = 7.4, P = 0.007). The appropriate MPT cut-off value for identifying a VE/VCO2 slope ≤ 34 was 18.12 seconds. An MPT value of 18.12 seconds may be a useful target value for identifying CHF patients with a VE/VCO2 slope ≤ 34 and for risk management in these patients.
ISSN:1536-5964
DOI:10.1097/MD.0000000000000306