Utility of the Seattle Heart Failure Model in patients with advanced heart failure.
OBJECTIVE
The aim of this study was to validate the Seattle Heart Failure Model (SHFM) in patients with advanced heart failure (HF).


BACKGROUND
The SHFM was developed primarily from clinical trial databases and extrapolated the benefit of interventions from published data.


METHODS
We evaluated the discrimination and calibration of SHFM in 445 advanced HF patients (age 52 +/- 12 years, 68.5% male, 52.4% white, ejection fraction 18 +/- 8%) referred for cardiac transplantation. The primary end point was death (n = 92), urgent transplantation (n = 14), or left ventricular assist device (LVAD) implantation (n = 3); a secondary analysis was performed on mortality alone.


RESULTS
Patients were receiving optimal therapy (angiotensin-II modulation 92.8%, beta-blockers 91.5%, aldosterone antagonists 46.3%), and 71.0% had an implantable device (defibrillator 30.4%, biventricular pacemaker 3.4%, combined 37.3%). During a median follow-up of 21 months, 109 patients (24.5%) had an event. Although discrimination was adequate (c-statistic >0.7), the SHFM overall underestimated absolute risk (observed vs. predicted event rate: 11.0% vs. 9.2%, 21.0% vs. 16.6%, and 27.9% vs. 22.8% at 1, 2, and 3 years, respectively). Risk underprediction was more prominent in patients with an implantable device. The SHFM had different calibration properties in white versus black patients, leading to net underestimation of absolute risk in blacks. Race-specific recalibration improved the accuracy of predictions. When analysis was restricted to mortality, the SHFM exhibited better performance.


CONCLUSIONS
In patients with advanced HF, the SHFM offers adequate discrimination, but absolute risk is underestimated, especially in blacks and in patients with devices. This is more prominent when including transplantation and LVAD implantation as an end point.
Kalogeropoulos
Andreas P
AP
Emory University, Atlanta, GA 30322, USA.
Georgiopoulou
Vasiliki V
VV
Giamouzis
Grigorios
G
Smith
Andrew L
AL
Agha
Syed A
SA
Waheed
Sana
S
Laskar
Sonjoy
S
Puskas
John
J
Dunbar
Sandra
S
Vega
David
D
Levy
Wayne C
WC
Butler
Javed
J
D000328:Adult; D005260:Female; D006333:Heart Failure / Q000453:epidemiology*; D016027:Heart Transplantation; D006353:Heart-Assist Devices; D006801:Humans; D008297:Male; D008875:Middle Aged; D015233:Models, Statistical; D011379:Prognosis; D012720:Severity of Illness Index