Table 5. Risk Assessment Combining STS Risk Estimate, Frailty,
Major Organ System Dysfunction, and Procedure-
Specific Impediments
Low Risk
(Must Meet ALL
Criteria in is
Column)
Intermediate
Risk (Any 1
Criterion in is
Column)
High Risk
(Any 1 Criterion in
is Column)
Prohibitive Risk
(Any 1 Criterion in is
Column)
STS PROM
a
<4%
AND
4%-8%
OR
>8%
OR
Predicted risk with
surgery of death or
major morbidity
(all-cause)
OR
Frailty
b
None
AND
1 index (mild)
OR
≥2 indices
(moderate to
severe)
OR
>50% at 1 y OR
Major organ
system
compromise not
to be improved
postoperatively
c
None
AND
1 organ system
OR
No more than
2 organ systems
OR
≥3 organ systems
OR
Procedure-
specific
impediment
d
None Possible
procedure-specific
impediment
Possible
procedure-specific
impediment
Severe procedure-
specific impediment
a
Use of the STS PROM to predict risk in a given institution with reasonable reliability is appropriate only
if institutional outcomes are within 1 standard deviation of STS average observed/expected ratio for the
procedure in question.
b
Seven frailty indices: Katz Activities of Daily Living (independence in feeding, bathing, dressing,
transferring, toileting, and urinary continence) and independence in ambulation (no walking aid or
assist required or 5-meter walk in <6 s). Other scoring systems can be applied to calculate no, mild-, or
moderate-to-severe frailty.
c
Examples of major organ system compromise: Cardiac—severe LV systolic or diastolic dysfunction or
RV dysfunction, fixed PHTN; CKD stage 3 or worse; pulmonary dysfunction with FEV1 <50% or
DLCO
2
<50% of predicted; CNS dysfunction (dementia, Alzheimer's disease, Parkinson's disease, stroke
with persistent physical limitation); GI dysfunction—Crohn's disease, ulcerative colitis, nutritional
impairment, or serum albumin <3.0; cancer—active malignancy; and liver—any history of cirrhosis,
variceal bleeding, or elevated INR in the absence of VKA therapy.
d
Examples: tracheostomy present, heavily calcified ascending aorta, chest malformation, arterial coronary
gra adherent to posterior chest wall, or radiation damage.
Table 4. Stages of Progression of VHD
Stage Definition Description
A At risk Patients with risk factors for development of VHD
B Progressive Patients with progressive VHD (mild-to-moderate severity and
asymptomatic)
C Asymptomatic
severe
Asymptomatic patients who meet the criteria for severe VHD:
C1: Asymptomatic patients with severe VHD in whom the le or
right ventricle remains compensated
C2: Asymptomatic patients with severe VHD, with
decompensation of the le or right ventricle
D Symptomatic
severe
Patients who have developed symptoms as a result of VHD
Evaluation
