The Need for a Specific Risk Prediction System in Native Valve Infective Endocarditis Surgery

Table 3

Definition of the 4 risk groups according to total score and comparisons in terms of clinically relevant variables.

	Class 1	Class 2	Class 3	Class 4	𝑃
Total score range	0–5	7–13^1	14–19	≥20
Mean predicted mortality	1±0.7%	3.7±1.6%	12±5%	43±18%
Age (years)	34±9	55±13	52±17	64±11	<0.001
Sex (female)	30%	20%	37%	39%	0.06
Active IE	81%	79%	91%	89%	0.08
Site: Aortic	47%	44%	51%	41%	0.03
Mitral	27%	27%	16%	22%
Tricuspid	6%	11%	9%	9%
Mitroaortic	11%	16%	21%	26%
Other	9%	2%	3%	2%
NYHA class IV	—	1.7%	52%	59%	<0.001
Diabetes	3%	12%	22%	18%	<0.001
Renal failure	4%	8%	27%	39%	<0.001
Period: before 2000	39%	40%	14%	7%	0.003
2000–2010	26%	42%	16%	16%
Positive latest preop. culture	5%	17%	19%	44%	<0.001
Perivalvular involvement	4%	12%	27%	44%	<0.001
Preop. ventilatory support	—	—	6%	30%	<0.001
Emergency	0.7%	4%	22%	59%	<0.001
Infection persistence postop.	2%	2%	9%	29%	<0.001

¹Note that the 6-point score cannot be obtained by any sum of scores in this system.