Aortic Valve Operations

The aortic valve is a one-way valve between the heart and the aorta, the vessel that supplies blood to the rest of the body. When the heart contracts, blood flows from the heart, through the aortic valve and into the aorta and the rest of the body. Between contractions, the valve closes, preventing blood from flowing backwards into the heart.

Operations on the aortic valve are done to repair or replace a damaged valve. Damage can cause heart failure and can occur from a congenital defect, the natural aging process, or from infection or scarring. Aortic valve operations include replacement of the valve or repair of the existing valve.

Aortic valve operations are also performed for patients who require repair of the aorta near the aortic valve. In some of these cases, it is possible to preserve or spare the existing valve instead of replacing it.

As one of the largest aortic valve programs in the country, the University of Michigan Health System treats many patients with complex aortic valve problems. When evaluating our performance, it is important to consider several types of measures, including the volume of procedures and the success (or outcome) of the procedure. The Society of Thoracic Surgeons (STS) provides national benchmarks for this procedure to help hospitals evaluate their performance. As you review the graphs below, you'll see that the University of Michigan Health System often exceeds the STS national benchmarks.

Procedure volume is the number of times a procedure was performed and is often used to assess clinical experience and expertise. The following graphs display the total number of aortic valve operations and the number of "isolated" aortic valve replacement operations.

Total Number of Aortic Valve Operations

Details

Why is This Measure Important?

This is a measure of the volume, or number of aortic valve operations. The number is composed of aortic valve replacement, aortic valve repair and aortic valve sparing operations. Aortic valve sparing is done to preserve the existing valve for patients who require a repair of their aorta near the aortic valve. It is important to consider both volume and outcome measures when assessing quality of care.

How is UMHS Performing?

Surgeons at the University of Michigan Health System perform a substantial and increasing number of aortic valve operations. UMHS has one of the largest aortic valve programs in the country and our cardiac surgeons treat many patients with complex aortic valve problems.

UMHS Source: University of Michigan Cardiac Surgery Clinical Database.

Number of Aortic Valve Replacement Operations

Details

Why is This Measure Important?

This is a measure of the volume, or number of "isolated" aortic valve replacement operations. The measure includes aortic valve replacement operations only. It does not include aortic valve repair or valve sparing operations or aortic valve replacement operations that are performed at the same time as heart bypass (coronary artery bypass graft or CABG) or other heart procedures.

How is UMHS Performing?

The University of Michigan Health System performs a substantial number of isolated aortic valve operations. UMHS has one of the largest aortic valve programs in the country and our cardiac surgeons treat many patients with complex aortic valve problems.

UMHS Source: University of Michigan Cardiac Surgery Clinical Database.

In this section, we evaluate the success of the isolated aortic valve replacement procedures by measuring the occurrence of complications within 30 days after the procedure was performed. We compare our rates to the national average, provided by the Society of Thoracic Surgeons (STS). The risk of developing complications depends on many factors, including the patient's health condition prior to undergoing the procedure. The risk of the patients we treat may be greater than the risk of patients represented in the STS average, because the University of Michigan Health System treats many complex patients who have heart disease and other serious medical problems. However, as the graphs below show, UMHS is successful in managing these complex cases.

In all of these graphs, a lower percentage means fewer complications and better performance. The graphs show that our complication and death rates are often lower than the STS national average.

Wound Infections w/in 30 Days of Operation
Higher Value = Better Performance

Details

Why is This Measure Important?

Wound infections following isolated aortic valve replacement procedures that involve the breastbone or that are deep within the chest are serious infections. Patients with diabetes or who are obese have a greater risk of developing a wound infection. For this and all other outcome measures, lower percentages are better.

How is UMHS Performing?

The University of Michigan Health System's performance was above the national average reported by the Society of Thoracic Surgeons (STS). Each occurrence is reviewed in order to identify opportunities for improvement. We continually strive to reduce the occurrence of infections.

UMHS Source: University of Michigan Cardiac Surgery Clinical Database.
Comparison Group Source: National performance from Society of Thoracic Surgeons.

Kidney Problems w/in 30 Days of Operation
Higher Value = Better Performance

Details

Why is This Measure Important?

Kidney problems are another complication for patients undergoing isolated aortic valve replacement. Patients with a history of kidney disease have a greater risk of kidney problems after aortic valve replacement. Most patients recover their kidney function in the weeks following surgery. For this and all other outcome measures, lower percentages are better.

How is UMHS Performing?

In three of the five years, including the most recent year, the University of Michigan Health System's performance was lower than the national average reported by the Society of Thoracic Surgeons (STS). All of the patients who experienced kidney problems in 2013 recovered their kidney function.

UMHS Source: University of Michigan Cardiac Surgery Clinical Database.
Comparison Group Source: National performance from Society of Thoracic Surgeons.

Stroke within 30 Days of Operation
Higher Value = Better Performance

Details

Why is This Measure Important?

Stroke is a possible complication for patients undergoing isolated aortic valve replacement. Older patients and patients with previous history of stroke have a greater risk of stroke after valve replacement. For this and all other outcome measures, lower percentages are better.

How is UMHS Performing?

The UMHS results for this measure are highly variable; a small change in the number of patients with this outcome can affect the rate substantially from year-to-year. In four of the five years, the University of Michigan Health System's performance was better than the national average reported by the Society of Thoracic Surgeons (STS).

UMHS Source: University of Michigan Cardiac Surgery Clinical Database.
Comparison Group Source: National performance from Society of Thoracic Surgeons.

Deaths within 30 Days of Operation
Higher Value = Better Performance

Details

Why is This Measure Important?

The mortality rate is the percentage of patients who die after undergoing isolated aortic valve replacement. This is a measure of mortality rate within 30 days after an isolated aortic valve replacement procedure. For this and all other outcome measures, lower percentages are better.

How is UMHS Performing?

The results for this measure are highly variable; a small change in the number of patients with this outcome can affect the rate substantially from year-to-year. In four of the five years, the University of Michigan Health System's performance was better than the national average reported by the Society of Thoracic Surgeons (STS). We treat patients who are referred to us from across the country. As a consequence, a significant number of our patients are high risk; they have other conditions, like infections, heart failure and pre-operative kidney failure. The complexity of our patients contributes to the variation in results.

UMHS Source: University of Michigan Cardiac Surgery Clinical Database.
Comparison Group Source: National performance from Society of Thoracic Surgeons.