title: Usefulness of cardiac index and peak exercise oxygen consumption for determining priority for cardiac transplantation.
abstract: Decisions regarding cardiac transplantation listing are difficult in patients with heart failure who have relatively discordant peak exercise oxygen consumption (Vo(2)) and cardiac index (CI) values. One hundred five patients with heart failure who underwent cardiopulmonary exercise testing and right-sided cardiac catheterization for transplantation evaluation were studied. Patients were divided into 4 groups on the basis of peak Vo(2) and CI: group 1, Vo(2) > or = 12 ml/min/kg, CI > or = 1.8 L/min/m(2) (n = 30); group 2, Vo(2) > or = 12 ml/min/kg, CI <1.8, L/min/m(2) (n = 27); group 3, Vo(2) <12 ml/min/kg, CI > or = 1.8 L/min/m(2) (n = 25); and group 4, Vo(2) <12 ml/min/kg, CI <1.8 L/min/m(2) (n = 23). Groups were compared for event-free (death or ventricular assist device) survival. The overall CI was 1.9 + or - 0.4 L/min/m(2) and peak Vo(2) was 12.4 + or - 2.8 ml/min/kg; values in the 4 groups were as follows: group 1, peak Vo(2) 14.7 + or - 2.1 ml/min/kg, CI 2.2 + or - 0.3 L/min/m(2); group 2, peak VO(2) 14.2 + or - 1.3 ml/min/kg, CI 1.5 + or - 0.2 L/min/m(2); group 3, peak Vo(2) 10.2 + or - 1.3 ml/min/kg, CI 2.1 + or - 0.3 L/min/m(2); and group 4, peak Vo(2) 9.7 + or - 2.0 ml/min/kg, CI 1.6 + or - 0.2 L/min/m(2). After a median follow-up period of 3.7 years, 28 patients (26.0%) had events. Event-free survival was 96%, 95%, 96%, and 79% for 6 months (p = 0.04); 88%, 81%, 90%, and 73% for 12 months (p = 0.09); 88%, 73%, 85%, and 65% for 18 months (p = 0.11); and 83%, 73%, 79%, and 53% for 24 months (p = 0.06) for groups 1 to 4, respectively. Median survival was 5.1, 3.0, 3.9, and 2.6 years, respectively, in groups 1 to 4 (p = 0.052). In conclusion, almost half the patients had relatively discordant peak Vo(2) and CI measurements. Patients with lower peak Vo(2) values but relatively preserved CI values had survival comparable to post-transplantation survival, whereas those with low CI but preserved Vo(2) had a lower survival rate. These results suggest that the former group may be safely monitored on medical therapy, whereas the latter may benefit from early listing.
authors.affiliation: Emory University, Atlanta, Georgia.
authors.forename: Amanda
authors.initials: A
authors.lastname: Methvin
authors.forename: Vasiliki V
authors.initials: VV
authors.lastname: Georgiopoulou
authors.forename: Andreas P
authors.initials: AP
authors.lastname: Kalogeropoulos
authors.forename: Adnan
authors.initials: A
authors.lastname: Malik
authors.forename: Perry
authors.initials: P
authors.lastname: Anarado
authors.forename: Mahdi
authors.initials: M
authors.lastname: Chowdhury
authors.forename: Imad
authors.initials: I
authors.lastname: Hussain
authors.forename: Wendy M
authors.initials: WM
authors.lastname: Book
authors.forename: Sonjoy R
authors.initials: SR
authors.lastname: Laskar
authors.forename: J David
authors.initials: JD
authors.lastname: Vega
authors.forename: Andrew L
authors.initials: AL
authors.lastname: Smith
authors.forename: Javed
authors.initials: J
authors.lastname: Butler
mesh_terms: D006328:Cardiac Catheterization; D005080:Exercise Test / Q000379:methods; D017079:Exercise Tolerance / Q000502:physiology*; D005260:Female; D005500:Follow-Up Studies; D006333:Heart Failure / Q000175:diagnosis / Q000503:physiopathology / Q000601:surgery*; D016027:Heart Transplantation; D006801:Humans; D008297:Male; D008875:Middle Aged; D009200:Myocardial Contraction / Q000502:physiology; D010101:Oxygen Consumption / Q000502:physiology*; D018579:Patient Selection; D015203:Reproducibility of Results; D012189:Retrospective Studies; D013997:Time Factors; D016276:Ventricular Function / Q000502:physiology*; D014850:Waiting Lists