Angioplasty and Stents

Angioplasty, also called percutaneous coronary intervention (PCI), is a procedure used to open clogged heart arteries to improve blood flow to the heart. The arteries are clogged because of a build-up of fats in and on the artery walls. Angioplasty involves temporarily inserting and blowing up a tiny balloon where your artery is clogged to help widen the artery. Angioplasty is often combined with placement of a small wire mesh tube called a stent to help prop the artery open and decrease the chance of it narrowing again.

Angioplasty can improve some of the symptoms of blocked arteries, such as chest pain and shortness of breath. Angioplasty can also be used during a heart attack to quickly open a blocked artery and reduce the amount of damage to your heart. However, depending on the extent of your disease, a heart bypass operation rather than angioplasty may be indicated.

Procedure volume is the number of times a procedure was performed and is used to assess clinical experience and expertise. Studies have linked higher volumes with more successful outcomes for some types of procedures. The following graphs display the number of angioplasty procedures performed at the University of Michigan Health System.

Number of Angioplasty / Stent Procedures

Details

Why is This Measure Important?

Health systems that perform a high number of angioplasty procedures are likely to have better outcomes, such as higher survival rates. The American College of Cardiology and Society of Coronary Angiography and Intervention recommend that institutions that perform angioplasty and stenting perform a minimum of 200 cases and ideally 400 procedures per year. This is a measure of the volume, or number of angioplasty and stent procedures.

How is UMHS Performing?

Cardiologists at the University of Michigan Health System consistently exceeded the ideal volume benchmarks recommended by the American College of Cardiology.

UMHS Source: Hospital administrative data and chart review.
Comparison Group Source: American College of Cardiology recommended volume.

Number of Angioplasty and Stent Procedures for Treatment of Heart Attack

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Why is This Measure Important?

This is a measure of the volume, or number of patients with major heart attacks who are treated emergently with angioplasty and stenting. The American College of Cardiology and Society of Coronary Angiography and Intervention guidelines recommend that institutions perform at least 36 procedures every year. Recent studies suggest that the outcomes are best at sites that perform more than 50 such procedures annually.

How is UMHS Performing?

Cardiologists at the University of Michigan Health System perform a high volume of angioplasty and stenting procedures to treat patients with a major heart attack. Our volume exceeds benchmarks recommended by the American College of Cardiology.

UMHS Source: Hospital administrative data and chart review.
Comparison Group Source: American College of Cardiology recommended volume.

The following graph describes the performance of the University of Michigan Health System by measuring the extent to which we follow best practices when performing angioplasty and stenting procedures. These best practices are also called evidence-based processes of care. When followed, they lead to better outcomes.

Rapid Treatment of Heart Attack
Lower Value = Better Performance

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Why is This Measure Important?

Door to balloon time reflects the time it takes from the moment a patient with a major heart attack arrives at the hospital to the time a cardiologist opens the clogged artery using a balloon, stent or other device. Shorter time means quicker treatment. This is a measure of the median time from door to balloon. The American Heart Association and American College of Cardiology has established a time of 90 minutes or less as the goal. For this measure, lower times are better.

How is UMHS Performing?

The University of Michigan Health System has been a leader in the field of rapid treatment of heart attacks. Our door-to-balloon times have been historically low and the staff have been working to lower them even further.

UMHS Source: Hospital administrative data and chart review.
Comparison Group Source: American College of Cardiology goal of 90 minutes or less.

In this section, we evaluate the success of the angioplasty and stenting procedures by measuring the occurrence of complications. The risk of developing complications depends on many factors, including the patient's health condition prior to undergoing the procedure. We compare our performance to what is expected, given the risk of the patients we treat or to goals established by the Blue Cross Blue Shield of Michigan Cardiovascular Collaborative, a group of hospitals from Michigan that have been working together for many years to improve the quality of care for patients undergoing angioplasty and stenting.

In all of these graphs, a lower score means fewer complications and better performance. The graphs show that most patients who underwent an angioplasty and stenting procedure at the University of Michigan Health System rarely experience complications and our patients have lower complications when compared to goals established by the Blue Cross Blue Shield of Michigan Cardiovascular Collaborative.

Death Rates: Observed and Expected
Higher Value = Better Performance

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Why is This Measure Important?

Death in patients undergoing coronary angioplasty and stenting is uncommon but can occur in patients with complicated medical problems. Because the risk of death differs between patients, we compare our actual performance to what is expected given the risk of the patients we treat. The expected mortality rate is provided by the Blue Cross Blue Shield of Michigan Cardiovascular Collaborative. Actual mortality rates are often close to the expected rates. Actual mortality rates that are much lower than expected mean better performance.

How is UMHS Performing?

Cardiologists at the University of Michigan Health System treat patients with complex coronary artery disease. Our health system has a rigorous quality improvement process and the case history of all patients who die after undergoing a stenting procedure are reviewed in detail to assess for opportunities for improvement.

UMHS Source: Hospital administrative data and chart review.
Comparison Group Source: Blue Cross Blue Shield of Michigan Cardiovascular Collaborative (BMC2) risk adjusted expected mortality rate.

Blood Vessel Injury During Procedure
Higher Value = Better Performance

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Why is This Measure Important?

During the angioplasty and stenting procedure, the catheter (long thin tube with the balloon or stent) that is used to open the clogged artery of the heart is inserted into the body through an artery in the leg. This is a measure of injuries to the artery of the leg during a procedure. For this and other outcome measures, lower rates are better.

How is UMHS Performing?

The Blue Cross Blue Shield of Michigan Cardiovascular Collaborative (BMC2) established a goal of less than 3% for all hospitals in the State of Michigan. At the University of Michigan Health System, the occurrence of these complications has been lower than 3% during the past five years. Our performance surpasses the BMC2 goal.

UMHS Source: Hospital administrative data and chart review.
Comparison Group Source: Blue Cross Blue Shield of Michigan Cardiovascular Collaborative (BMC2) goal of less than 3.0%.

Kidney Problems After Procedure
Higher Value = Better Performance

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Why is This Measure Important?

Kidney problems are a rare but well-known complication for patients undergoing angioplasty and stenting and can be caused by intravenous dye that is used during the procedure to visualize the clogged artery. Patients with a history of kidney disease will have a greater risk of kidney problems after angioplasty. In extreme cases, patients may require dialysis. For this and all other outcome measures, lower rates are better.

How is UMHS Performing?

The Blue Cross Blue Shield of Michigan Cardiovascular Collaborative (BMC2) established 0.4% or less as the goal that hospitals in Michigan should try to achieve. The occurrence of kidney problems has been increasing at the University of Michigan Health System due to a rigorous program of minimizing the amount of contrast dye that is used during angioplasty and stenting procedures.

UMHS Source: Hospital administrative data and chart review.
Comparison Group Source: Blue Cross Blue Shield of Michigan Cardiovascular Collaborative (BMC2) goal of less than or equal to 0.4%.

Blood Transfusion After Procedure
Higher Value = Better Performance

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Why is This Measure Important?

This is a measure of the percentage of patients who receive a blood transfusion after a procedure. Patients who receive unnecessary blood transfusions after angioplasty and stenting have been shown to experience worse health outcomes in the long term. For this and other outcome measures, lower rates are better.

How is UMHS Performing?

The Blue Cross Blue Shield of Michigan Cardiovascular Collaborative (BMC2) established a goal for transfusion rate of less than 5% for hospitals that perform angioplasty and stenting. The University of Michigan Health System has had a historically low rate of transfusion and these rates have been consistently better than the BMC2 goal.

UMHS Source: Hospital administrative data and chart review.
Comparison Group Source: Blue Cross Blue Shield of Michigan Cardiovascular Collaborative (BMC2) goal of less than 5.0%.