title: Muscle strength as a predictor of long-term survival in severe congestive heart failure.
abstract: OBJECTIVE
  The objective of the study was to test the relationship between isolated muscle strength and outcome, and its significance in the context of other exercise variables.
  
  
  RESULTS
  122 consecutive patients (LVEF 21+/-7%) were enrolled in the study. Isokinetic strength testing of the knee extensor and flexor muscles were performed. A subset of 51 patients underwent additional upright bicycle testing with gas exchange analysis. The outcome up to 60 months was defined by event-free survival (group A, n=59) or death (group B, n=34). Patients who had been transplanted were excluded from further analysis. The peak strength of the quadriceps muscle was comparable in both groups (N.S.). In contrast, the index (value adjusted for weight) did reveal significant differences (P<0.04), similar to the peak torque of the knee flexor muscle (P<0.04), whose index was even more significant with regard to differences (P<0.01). Multivariate analysis including muscle strength variables, pVO2 and workload into one model show that the flexor strength index is the only independent variable (x2=9 P<0.003). A cut-off point of 68 Nm x 100/kg in the strength index of the flexor muscles was used to establish a significant difference between groups with regard to outcome (P<0.01). Thus, the isokinetic strength of the knee flexor muscles is related to outcome. Moreover, this parameter is superior to variables such as peakVO2 and workload.
authors.affiliation: Department of Cardiology, University of Vienna, Währinger Gürtel 18-20, A-1090 Vienna, Austria. martin.huelsmann@univie.ac.at
authors.forename: Martin
authors.initials: M
authors.lastname: Hülsmann
authors.forename: Michael
authors.initials: M
authors.lastname: Quittan
authors.forename: Rudolf
authors.initials: R
authors.lastname: Berger
authors.forename: Richard
authors.initials: R
authors.lastname: Crevenna
authors.forename: Christoph
authors.initials: C
authors.lastname: Springer
authors.forename: Martin
authors.initials: M
authors.lastname: Nuhr
authors.forename: Deddo
authors.initials: D
authors.lastname: Mörtl
authors.forename: Petra
authors.initials: P
authors.lastname: Moser
authors.forename: Richard
authors.initials: R
authors.lastname: Pacher
mesh_terms: D000368:Aged; D017079:Exercise Tolerance / Q000502:physiology*; D005260:Female; D005500:Follow-Up Studies; D006333:Heart Failure / Q000401:mortality* / Q000503:physiopathology*; D006801:Humans; D007537:Isometric Contraction / Q000502:physiology; D007551:Isotonic Contraction / Q000502:physiology; D008297:Male; D008875:Middle Aged; D018482:Muscle, Skeletal / Q000503:physiopathology*; D010101:Oxygen Consumption; D011237:Predictive Value of Tests; D012720:Severity of Illness Index; D015996:Survival Rate