TY - JOUR
T1 - Ventilatory gas exchange and early response to cardiac resynchronization therapy
AU - Kim, Chul Ho
AU - Olson, Lyle J.
AU - Shen, Win K.
AU - Cha, Yong Mei
AU - Johnson, Bruce D.
N1 - Funding Information:
The authors have no conflicts of interest to disclose. This study was supported by grants from the National Institutes of Health (HL98663 and HL71478).
Publisher Copyright:
© 2015 International Society for Heart and Lung Transplantation.
PY - 2015/11
Y1 - 2015/11
N2 - Background Cardiac resynchronization therapy (CRT) is an accepted intervention for chronic heart failure (HF), although approximately 30% of patients are non-responders. The purpose of this study was to determine whether exercise respiratory gas exchange obtained before CRT implantation predicts early response to CRT. Methods Before CRT implantation, patients were assigned to either a mild-moderate group (Mod G, n = 33, age 67 ± 10 years) or a moderate-severe group (Sev G, n = 31, age 67 ± 10 years), based on abnormalities in exercise gas exchange. Severity of impaired gas exchange was based on a score from the measures of VE/VCO2 slope, resting PETCO2 and change of PETCO2 from resting to peak. All measurements were performed before and 3 to 4 months after CRT implantation. Results Although Mod G did not have improved gas exchange (p > 0.05), Sev G improved significantly (p < 0.05) post-CRT. In addition, Mod G did not show improved right ventricular systolic pressure (RSVP; pre vs post: 37 ± 14 vs 36 ± 11 mm Hg, p > 0.05), yet Sev G showed significantly improved RVSP, by 23% (50 ± 14 vs 42 ± 12 mm Hg, p < 0.05). Both groups had improved left ventricular ejection fraction (p < 0.05), New York Heart Association class (p < 0.05) and quality of life (p < 0.05), but no significant differences were observed between groups (p > 0.05). No significant changes were observed in brain natriuretic peptide in either group post-CRT. Conclusion Based on pre-CRT implantation ventilatory gas exchange, subjects with the most impaired values appeared to have more improvement post-CRT, possibly associated with a decrease in RVSP.
AB - Background Cardiac resynchronization therapy (CRT) is an accepted intervention for chronic heart failure (HF), although approximately 30% of patients are non-responders. The purpose of this study was to determine whether exercise respiratory gas exchange obtained before CRT implantation predicts early response to CRT. Methods Before CRT implantation, patients were assigned to either a mild-moderate group (Mod G, n = 33, age 67 ± 10 years) or a moderate-severe group (Sev G, n = 31, age 67 ± 10 years), based on abnormalities in exercise gas exchange. Severity of impaired gas exchange was based on a score from the measures of VE/VCO2 slope, resting PETCO2 and change of PETCO2 from resting to peak. All measurements were performed before and 3 to 4 months after CRT implantation. Results Although Mod G did not have improved gas exchange (p > 0.05), Sev G improved significantly (p < 0.05) post-CRT. In addition, Mod G did not show improved right ventricular systolic pressure (RSVP; pre vs post: 37 ± 14 vs 36 ± 11 mm Hg, p > 0.05), yet Sev G showed significantly improved RVSP, by 23% (50 ± 14 vs 42 ± 12 mm Hg, p < 0.05). Both groups had improved left ventricular ejection fraction (p < 0.05), New York Heart Association class (p < 0.05) and quality of life (p < 0.05), but no significant differences were observed between groups (p > 0.05). No significant changes were observed in brain natriuretic peptide in either group post-CRT. Conclusion Based on pre-CRT implantation ventilatory gas exchange, subjects with the most impaired values appeared to have more improvement post-CRT, possibly associated with a decrease in RVSP.
KW - exercise
KW - heart failure
KW - pulmonary hypertension
KW - right ventricle pressure
KW - ventilatory efficiency
UR - http://www.scopus.com/inward/record.url?scp=84946482834&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=84946482834&partnerID=8YFLogxK
U2 - 10.1016/j.healun.2015.05.016
DO - 10.1016/j.healun.2015.05.016
M3 - Article
C2 - 26163155
AN - SCOPUS:84946482834
VL - 34
SP - 1430
EP - 1435
JO - Journal of Heart and Lung Transplantation
JF - Journal of Heart and Lung Transplantation
SN - 1053-2498
IS - 11
ER -