STS Database Participant

An STS National Database “Participant” is a cardiothoracic surgeon or group of cardiothoracic surgeons who agree to submit case records for analysis and comparison with benchmarking data for quality improvement initiatives. At the option of the surgeon or surgical group, the Participant can include a hospital and/or associated anesthesiologists (ACSD and CHSD).

Four components of the STS National Database

The STS National Database has four components, each focusing on a different area of cardiothoracic surgery—Adult Cardiac Surgery (ACSD), Congenital Heart Surgery (CHSD), General Thoracic Surgery (GTSD), and the Interagency Registry for Mechanically Assisted Circulatory Support (Intermacs) Database. By participating in the STS National Database, cardiothoracic surgeons demonstrate their commitment to improving the quality of care that their patients receive.

Coronary artery blockage

A coronary artery blockage is a narrowing of the arteries around the heart such that oxygen-rich blood cannot reach the heart muscle.

Coronary artery bypass graft (CABG) surgery

CABG (often pronounced “cabbage”) is the most commonly performed heart operation in the US. The operation is designed to bypass blockages in the patient’s coronary arteries in order to restore normal or near normal bloodflow to the entire heart during rest and exercise. Though an occasional patient needs only one bypass graft, most people who are candidates for CABG have blockages in several of their coronary arteries and need between three and five bypass grafts.   

The surgeon will take a healthy blood vessel (artery or vein from the patient’s body), usually from the leg, arm, chest or abdomen, and use it to “bypass,” or go around, the diseased or blocked portion of the coronary artery, creating a new path for bloodflow to the heart.  

To learn more about coronary artery bypass grafting and coronary artery disease, see the STS patient website at ctsurgerypatients.org.

Aortic valve replacement (AVR) surgery

Aortic valve replacement is a procedure performed by a cardiothoracic surgeon during which a patient’s failing aortic valve is replaced with a mechanical or biological heart valve. The aortic valve can be affected by a range of diseases, as well as by the normal aging process. As a result, the valve can either become leaky (aortic regurgitation) or partially blocked (aortic stenosis).

 To learn more about aortic valve disease, see the STS patient website at ctsurgerypatients.org.

Adult cardiac surgery operations

These are surgeries of the heart performed on patients aged 18 years and above, including CABG and heart valve surgeries.

Risk adjustment

Risk adjustment is a way to measure surgical results that takes into consideration how sick the patients were before treatment.

Operative mortality rate

The mortality rate is the percentage of patients undergoing heart surgery who died during the hospitalization in which the surgery was performed and those who died within 30 days of the surgery if they were discharged from the hospital.

Morbidity rate

The morbidity rate, also known as complication rate, is the percentage of patients undergoing heart surgery, who experienced at least one of the five most serious complications of cardiac surgery: reoperation, stroke, kidney failure, infection of the chest wound, or prolonged need to be supported by a breathing machine or ventilator.

Perioperative period

“Perioperative” refers to all three stages of surgery: preoperative (before surgery), intraoperative (during surgery), and postoperative (after surgery).

Quality performance measure

A quality performance measure is a numeric calculation of health care quality that can be used to monitor, assess, and improve the quality of patient care.

STS CABG composite score

The STS CABG composite score is calculated using a combination of 11 quality measures divided into four categories or domains.

1.  Absence of Operative Mortality
The first domain is measured by the percentage of patients who do not die during the hospitalization in which the surgery was performed and those who do not die within the 30 days of the surgery if they were discharged from the hospital. STS adjusts the results for each surgeon and hospital by accounting for the severity of their patient's illnesses, a process known as risk adjustment. To level the playing field, statistical techniques have been developed to account for the condition of patients before surgery.

2.  Absence of Major Morbidity
A second domain is the risk-adjusted absence of major morbidity, the percentage of patients who leave the hospital with none of the five most serious complications (often referred to as morbidities)—reoperation, stroke, kidney failure, infection of the chest wound, or prolonged need to be supported by a breathing machine (ventilator).

3.  Use of Internal Mammary Artery
The third domain measures the percentage of CABG procedures that include the use of at least one of the arteries from the underside of the chest wall—the internal mammary (or internal thoracic) artery—for bypass grafting. This artery has been shown to function much longer than vein grafts, which can become blocked over time. 

4. Receipt of Required Perioperative Medications
The fourth domain measures how often all of the four medications believed to improve a patient's immediate and long-term outcomes were prescribed. Those drugs include beta-blocking drugs prescribed perioperatively, as well as aspirin (or similar drugs to prevent graft clotting), and additional beta blockers and cholesterol-lowering medicines prescribed postoperatively.

Each database participant is scored in all of the four categories. The scores are combined using a statistical formula and the result is the overall composite score. In addition to a composite score, each participant also is given a star rating of one to three stars. Those participants who perform worse than expected receive a star rating of one, those who perform as expected receive a two star rating, and participants performing better than expected receive a three star rating.

AVR composite score

The AVR composite score is based on a combination of the NQF-endorsed isolated AVR operative mortality measure and the same morbidity outcomes that make up the NQF-endorsed CABG morbidity measures. Please note that there are currently no NQF-endorsed AVR morbidity measures. STS uses six quality measures grouped appropriately into two domains to assess quality of care.

1.  Absence of Operative Mortality
The first domain is measured by percentage of patients who do not die during the hospitalization in which the surgery was performed and those who do not die within the 30 days of the surgery if they were discharged from the hospital. STS adjusts the results for each surgeon and hospital by accounting for the severity of their patient's illnesses, a process known as risk adjustment. To level the playing field, statistical techniques have been developed to account for the condition of patients before surgery.

2.  Absence of Major Morbidity
A second domain is the risk-adjusted absence of major morbidity, the percentage of patients who leave the hospital with none of the five most serious complications (often referred to as morbidities)—reoperation, stroke, kidney failure, infection of the chest wound, or prolonged need to be supported by a breathing machine (ventilator).

Participants receive a score for each of the two domains, plus an overall composite score, which is calculated by “rolling up” the domain scores into a single number. In addition to receiving a numeric score, participants are assigned to a rating category designated by one to three stars.

AVR+CABG composite score

Similar to the AVR composite, the AVR+CABG composite score is based on a combination of the NQF-endorsed AVR+CABG operative mortality measure and the same morbidity outcomes that make up the NQF-endorsed CABG morbidity measures.

1.  Absence of Operative Mortality
The first domain is measured by percentage of patients who do not die during the hospitalization in which the surgery was performed and those who do not die within the 30 days of the surgery if they were discharged from the hospital. STS adjusts the results for each surgeon and hospital by accounting for the severity of their patient's illnesses, a process known as risk adjustment. To level the playing field, statistical techniques have been developed to account for the condition of patients before surgery.

2.  Absence of Major Morbidity
A second domain is the risk-adjusted absence of major morbidity, the percentage of patients who leave the hospital with none of the five most serious complications (often referred to as morbidities)—reoperation, stroke, kidney failure, infection of the chest wound, or prolonged need to be supported by a breathing machine (ventilator).

Participants receive a score for each of the two domains, plus an overall composite score. In addition to receiving a numeric score, participants are assigned to a rating category designated by one to three stars.

National Quality Forum (NQF)

The National Quality Forum (NQF) is a nonprofit organization whose primary function is to conduct a rigorous, evidence-based review of quality performance measures for the purpose of granting endorsement. NQF-endorsed measures are considered the gold standard for health care performance measurement.