Brophy et al developed models for predicting survival at 12 and 36 months for a patient with heart failure. This can help identify a patient who may benefit from more aggressive or a novel therapy. The authors are from McGill University, VA Medical Center at Perry Point, and McMaster University.
Parameters:
(1) left ventricular ejection fraction in percent (limits are from 3 to 45%)
(2) NYHA class
(3) cardiothoracic ratio in percent
(4) clinical signs and symptoms (peripheral edema, rales, elevated jugular venous pressure, dyspnea at rest or on exertion, S gallop, limited activity, pulmonary congestion on X-ray)
(5) serum creatinine in mg/dL over range of 0.3 to 3.0 mg/dL
(6) body mass index (BMI) in kg per square meter
(7) diastolic blood pressure in mm Hg
(8) etiology of the heart failure
points for the ejection fraction =
= 0.2927 * (45 - (percent LVEF)) / 10
points for serum creatinine =
= 0.6152 * (serum creatinine)
|
Parameter
|
Finding
|
Points
|
|
NYHA class
|
I
|
0
|
|
|
II
|
0.3646
|
|
|
III or IV
|
0.7293
|
|
cardiothoracic ratio in percent
|
<= 50%
|
0
|
|
|
> 50%
|
0.47
|
|
number of clinical signs
|
0 or 1
|
0
|
|
|
2 or 3
|
0.19
|
|
|
4 or 5
|
0.38
|
|
|
6 or 7
|
0.572
|
|
BMI
|
<= 23.6
|
0
|
|
|
23.7 to 26.4
|
0.1655
|
|
|
26.5 to 29.7
|
0.331
|
|
|
>= 29.8
|
0.4965
|
|
diastolic blood pressure
|
<= 69 mm Hg
|
0
|
|
|
70 to 74 mm Hg
|
0.157
|
|
|
75 to 80 mm Hg
|
0.314
|
|
|
>= 81 mm Hg
|
0.471
|
|
etiology
|
diabetic ischemic
|
0.3784
|
|
|
other
|
0
|
where:
• The points in the table are based on the natural logarithm of the hazard ratio (from Table 2) times the reference group from Table 1.
patient sum =
= (points for ejection fraction) + (points for serum creatinine) + SUM(points for points in table)+
Y =
= EXP((patient sum) - 3.42)
percent survival at 12 months =
= (0.888 ^ Y)
where:
• 3.42 is the mean value.
• 0.888 is the overall average 12 month survival.
