The effects of bilateral lung transplantation on ventilatory efficiency, oxygen uptake and the right heart: a two-yr follow-up.
BACKGROUND
This study was to examine the course of ventilation/perfusion mismatch (VE/VCO(2)-slope) before and during two-yr follow-up after bilateral lung transplantation (BLTx) and to relate exercise parameters with the reverse right ventricular remodeling.


METHODS
We prospectively examined 20 patients (nine women; age 46.0 ± 13.0 yr) by cardiopulmonary exercise testing (before and at 3, 6, 12, and 24 months after BLTx), and by echocardiography and blood gas analysis. Etiology of pulmonary failure was chronic obstructive pulmonary disease as well (n = 8), pulmonary hypertension (n = 7), idiopathic fibrosis (n = 3), others (n = 2).


RESULTS
The VE/VCO(2)-slope before BLTx was 47.5 (interquartile range 24.5) and declined at 3 months -25.9%, 6 months -30.9%, 12 months -33.9%, and 24 months -35.1% (all p ≤ 0.003) and was then not different from normal. The right ventricular end diastolic diameter RVEDd narrowed from 35.0 (22.5) before to 31.0 (9.0) mm at 3 months after LTx. Similarly, right ventricular systolic pressure (RV(sys)) decreased from 53.6 ± 28.3 to 26.2 ± 5.2 mmHg (all p < 0.01). RVEDd correlated with VE/VCO(2)-slope before (p < 0.0001) but not after BLTx. PeakVO(2) increased from 10.0 ± 2.3 mL/min per kg before BLTx by 86.5% at 24 months (p < 0.01).


CONCLUSIONS
The functional status (VE/VCO(2)-slope, peakVO(2)) improves quickly after lung transplantation and is accompanied by reverse remodeling of the right heart. A correlation between exercise parameters and right heart function was found before BLTx only.
Habedank
Dirk
D
Department of Cardiology, Charité- University Medicine Berlin, Campus Virchow, Germany. dirk.habedank@charite.de
Ewert
Ralf
R
Hummel
Manfred
M
Dandel
Michael
M
Habedank
Friedrich
F
Knosalla
Christoph
C
Lehmkuhl
Hans B
HB
Anker
Stefan D
SD
Hetzer
Roland
R
D000293:Adolescent; D000328:Adult; D000368:Aged; D004452:Echocardiography; D005080:Exercise Test; D017079:Exercise Tolerance / Q000502:physiology*; D005260:Female; D005500:Follow-Up Studies; D006333:Heart Failure / Q000503:physiopathology*; D006801:Humans; D006976:Hypertension, Pulmonary; D016040:Lung Transplantation; D008297:Male; D008875:Middle Aged; D010101:Oxygen Consumption / Q000502:physiology*; D011446:Prospective Studies; D011659:Pulmonary Gas Exchange / Q000502:physiology; D012123:Pulmonary Ventilation / Q000502:physiology*; D015996:Survival Rate; D016896:Treatment Outcome; D016278:Ventricular Function, Right / Q000502:physiology*; D055815:Young Adult