Bulk STS Risk Calculator Query Tool

Repeatedly query the Society of Thoracic Surgeons Adult Cardiac Risk Calculator using bulk .csv patient data.

Overview

This is a minimalist Python command line tool to query the STS risk calculator with bulk patient records. This returns all available mortality and complication data from the STS. There is no upper limit to your query size -- this has been successfully run on datasets of ~500+ patients.

The STS Calculator itself is a black box — patient parameters are passed to the STS API and a risk is returned (almost no computing happens client side). A few obvious parameters impact mortality heavily (e.g. ESRD).

Features

• Programmatically queries the STS Short-Term Risk Calculator (version 4.2)
• Parses input .csv records of patients
• Performs automatic validation of most input records
• Optionally override individual parameters from your bulk records
  • For example, how does mortality change if all patients have the same age or renal function?
• Returns all avalable STS risk model parameters (mortality, prolonged ventilation, reoperation, etc.)

Example Usage

You must provide a CSV with a unique id per row, followed by a minimum of procid, age, weightkg, and heightkg. All other parameters are optional.

The most critical step is formatting your data to exactly match the STS risk parameter names & values (detailed here). The calculator API is inflexible -- spacing, capitalization, etc. must be identical to the STS database.

0. Setup this script

For example, on Mac, open the Terminal app and enter:

git clone https://github.com/semenko/sts-risk-calculator-cli
cd sts-risk-calculator-cli
pip install -r requirements.txt

1. Define input patient .csv (e.g. sample_data.csv)

id,procid,age,gender,surgdt,weightkg,heightcm,creatlst,payorprim
1,1,56,Male,08/11/2017,72,124,1.5,"Commercial Health Insurance"
2,3,72,Female,12/16/2018,60,96,2.9,
3,4,42,Male,7/21/2021,50,110,1.2,"Non-U.S. Plan"

2. Run sts-query

$ ./sts-query.py --csv sample_data.csv --output sample_results.csv
Validating CSV entries...
Valid!

Querying STS API.
100%|█████████████████████████████████████████████████████████████| 3/3 [00:01<00:00,  2.34it/s]

Done!
Results written to: sample_results.csv

3. Inspect results

$ cat sample_results.csv
id,predmort,predmm,preddeep,pred14d,predstro,predvent,predrenf,predreop,pred6d
1,0.00698,0.05765,0.00317,0.02174,0.00269,0.03349,0.01563,0.01304,0.65328
2,0.10089,0.48756,0.0028,0.25896,0.01259,0.30205,0.21811,0.04919,0.06589
3,0.01906,0.14991,0.00416,0.04517,0.00802,0.0852,0.02145,0.03302,0.38684

The STS result abbreviations (e.g. predstro) are described here.

Full Options

$ ./sts-query.py
usage: sts-query.py [options]

Query the STS Short-Term Risk Calculator (v4.2) via a CSV.
Please cite this repository if you're using in a publication.

optional arguments:
  -h, --help            show this help message and exit
  --csv patient-data.csv
                        Your input patient data .csv. (default: None)
  --dry-run             Only validate data, do not query the STS API. (default: False)
  --output results.csv  Where to store results. (default: results.csv)
  --override stsvariable=value [stsvariable=value ...]
                        Override values sent to the STS API,
                        e.g. make all patients the same age with --override age=50 (default: None)

Override Parameters

Using the --override flag, you can provide parameters to the STS API that override or fill in missing data in your .csv. For example, you can pass --override age=50 to set the age of all patients to 50. You can provide multiple values, for example --override dialysis=Yes procid=2 will set every patient on dialysis and set the procid to 2 (AVR).

This can be useful when comparing mortality predictions associated with population-level interventions. For example, you can ask: What if all these patients stopped smoking? or What if everyone had good diabetes control?

Citation & License

If you use this in your publication, please consider citing this work as: STS Risk Calculator CLI, Nicholas P. Semenkovich, 2022. https://github.com/semenko/sts-risk-calculator-cli

Released under the MIT License. Copyright 2022, Nick Semenkovich <semenko@alum.mit.edu>

STS Result Abbreviations

STS Abbreviation	Value
predmort	Mortality
predrenf	Renal Failure
predstro	Permanent Stroke
predvent	Prolonged Ventilation
preddeep	Deep Surgical Infection
predreop	Reoperation
predmm	Morbidity or Mortality
pred6d	Short Length of Stay
pred14d	Long Length of Stay

STS Parameters

The STS Risk Calculator version 4.2 defines these parameters. Note that the API is a bit sketchy: abbreviations are difficult to decipher and erratic (e.g. sometimes "race" is truncated to "rac"), and types are strange (sometimes fields want integers, while other times they want strings like "Two" …).

STS Field ID	Description/Notes	Options
procid	Procedure ID (Required)	{CAB: 1, AVR: 2, MVR: 3, AVR+CAB: 4, MVR+CAB: 5, None: 6, MVRepair: 7, MVRepair+CAB: 8}
age	(Required)	1-110
gender		Male/Female/[Empty]
raceasian		Yes/[Empty]
raceblack		Yes/[Empty]
racenativeam		Yes/[Empty]
racnativepacific		Yes/[Empty]
ethnicity	Hispanic, latino, or spanish ethnicity	Yes/[Empty]
payorprim	Primary payor	(see STS site: "None / self", …)
payorsecond	Secondary payor (requires payorprim to be set)	…
surgdt	Surgery date	as MM/DD/YYYY
weightkg	(Required)	10-250
heightcm	(Required)	20-251
hct		1-100
wbc		0.1-100
platelets		1000-90,000
creatlst	Last creatinine	0.10-30
dialysis		Yes/[Empty]
hypertn		Yes/[Empty]
immsupp		Yes/[Empty]
pvd		Yes/[Empty]
cvd	Cerebrovascular disease	Yes/[Empty]
cvdtia	Prior TIA (requires cva=Yes)	Yes/[Empty]
cvdpcarsurg	Prior carotid artery surgery/stenting	Yes/[Empty]
mediastrad	Mediastinal radiation	Yes/[Empty]
cancer		Yes/[Empty]
fhcad		Yes/[Empty]
slpapn	Sleep apnea	Yes/[Empty]
liverdis		Yes/[Empty]
unrespstat	Unresponsive	Yes/[Empty]
syncope		Yes/[Empty]
diabetes		Yes/[Empty]
diabctrl	Diabetes control	(see STS site: "None", "Diet only" …)
infendo	Infective endocarditis	Yes/[Empty]
infendty	Endocarditis treatment status	Treated/Active
cva	Prior CVA	Yes/[Empty]
cvawhen	CVA timing	(see STS site)
chrlungd	Chronic lung disease	(see STS site)
cvdstenrt	Right carotid stenosis	(see STS site)
cvdstenlft	Left carotid stensosis	(see STS site)
ivdrugab	Illicit drug use	Yes/[Empty]
alcohol	EtOH Use	(see STS site)
pneumonia	Pneumonia	(see STS site)
tobaccouse	Smoking status	(see STS site)
hmo2	Home O2 Use	(see STS site)
prcvint	Prior CV intervention	(see STS site)
prcab	Prior CABG	Yes/[Empty]
prvalve	Prior valve	Yes/[Empty]
prvalveproc1	Prior valve procedure #1 type	(see STS site)
prvalveproc2	…	…
prvalveproc3	…	…
prvalveproc4	…	…
prvalveproc5	…	…
poc	Prior other cardiac procedure	Yes/[Empty]
pocint1	Prior other procedure #1	(see STS site: "Aortic valve balloon…")
pocint2	…	…
pocint3	…	…
pocint4	…	…
pocint5	…	…
pocint6	…	…
pocint7	…	…
pocpci	Prior PCI	Yes/[Empty]
pocpciwhen	PCI within this episode of care	(see STS site)
pocpciin	PCI Interval	(see STS site)
miwhen	MI Timing	(see STS site: "<=6 Hrs", … )
heartfailtmg	HF onset	Acute/Chronic/Both/[Empty]
classnyh	HF class	(see STS site: "Class I" … )
cardsymptimeofadm	Symptoms on admission	(see STS site: "Stable angina" …)
carshock	Shock at time of procedure	(see STS site: "Yes - At the time…" …)
arrhythatrfib	Afib	None / Remote (> 30 days preop) / Recent (<= 30 days preop)
arrhythafib	Afib type	Paroxysmal/Persistent
arrhythaflutter	Aflutter	None / Remote (> 30 days preop) / Recent (<= 30 days preop)
arrhyththird	3rd deg AVB	None / Remote (> 30 days preop) / Recent (<= 30 days preop)
arrhythsecond	2nd deg AVB	None / Remote (> 30 days preop) / Recent (<= 30 days preop)
arrhythsss	SSS	None/Remote (> 30 days preop)/Recent (<= 30 days preop)
arrhythvv	VF/VT	None/Remote (> 30 days preop)/Recent (<= 30 days preop)
medinotr	Inotropes	Yes/[Empty]
medadp5days	ADP-i/P2Y12	Yes/[Empty]
medadpidis	Days Since ADP-i Discontinued	0-5
medacei48	ACE/ARB	Yes/[Empty]
medbeta	Beta blocker	Yes/[Empty]
medster	Steroids	Yes/[Empty]
medgp	GP2B3A	Yes/[Empty]
resusc	Active resuscitation	(see STS site)
numdisv	Number of diseased vessels	None/One/Two/Three (String)
stenleftmain	L main stenosis	Yes/No/[Empty]
laddiststenpercent	% LAD stenosis	"50 - 69%" or ">=70%" or [Empty]
hdef	EF	1.0-99.0
vdstena	AS	Yes/[Empty]
vdstenm	MS	Yes/[Empty]
vdinsufa	AI	Yes/[Empty]
vdinsufm	MR	Yes/[Empty]
vdinsuft	TR	Yes/[Empty]
vdaoprimet	Valve indication	(see STS site)
incidenc	Incidence	(see STS site)
status	Status	(see STS site: Elective/Urgent/…)
iabpwhen	IABP Timing	Preop/Intraop/Postop/[Empty]
cathbasassistwhen	Cath assist	Preop/Intraop/Postop/[Empty]
ecmowhen	ECMO Timing	Preop/Intraop/Postop/Non-operative/[Empty]
calculatedbmi	Internally Calculated	Do not provide this value.