Following Heart Procedure, Kidneys May Be Injured

Acute kidney injury after coronary angioplasty is common and tied to increased death risk

/ Author:  / Reviewed by: Robert Carlson, M.D Beth Bolt, RPh

(RxWiki News) For over 20 years, coronary angioplasty has been used to open narrowed arteries and improve blood flow. The procedure, however, can cause complications, including harm to the kidneys.

Each year, more than 1 million patients have angioplasty to unblock coronary arteries, according to the American Heart Association. The procedure is generally safe, but there are possible risks — including blood clots, heart valve damage, heart attack, stroke and irregular heartbeats.

A new investigation found that this intervention may also lead to sudden loss of kidney function, which can develop within 48 hours.

"Ask a doctor about complications from heart procedures."

Thomas Tsai, MD, from the Institute for Health Research at Kaiser Permanente Colorado and the University of Colorado in Denver, and colleagues reviewed records on 985,737 patients from across the country who underwent percutaneous coronary invtervention (PCI).

PCI, also called angioplasty, involves threading a thin tube called a catheter through a blood vessel to the site of the blockage and inflating a small balloon to widen the artery. Then, in most cases, a stent (small mesh tube) is inserted to keep the vessel open.

Scientists discovered that just over seven percent (69,658) of patients in this study experienced acute kidney injury and 0.3 percent (3,005) required new dialysis.

Those with acute kidney injury were also more likely to die in the hospital. These patients had an in-hospital mortality rate of 9.7 percent, and those who required dialysis had a mortality rate of 34 percent. For those without acute kidney injury, the mortality rate was 0.5 percent.

Also called acute renal failure, acute kidney injury is the rapid loss the kidneys' ability to remove waste and help balance fluids and electrolytes in the body. When the kidneys fail, patients may require dialysis — a process using a machine to filter wastes, salts and fluids from the blood.

“Defining strategies to minimize the risk of acute kidney injury in patients undergoing PCI are needed to improve the safety and outcomes of the procedure,” wrote the authors.

They also highlighted that individuals who had a heart attack were more likely to develop acute kidney injury.

Sarah Samaan, MD, cardiologist and physician partner at the Baylor Heart Hospital in Plano, Texas, told dailyRx News, “During a heart attack, the heart strength may be diminished, and that means the kidneys may not get normal blood flow. The same thing happens in cardiogenic shock [damage to the heart muscle from a severe heart attack]. As a result, the kidneys have a harder time clearing toxins from the blood stream and are more vulnerable to injury."

While angioplasty can restore blood flow, it does not cure the cause of artery blockage and blood vessels may become narrow again.

MedlinePlus advises patients to follow a heart-healthy diet, exercise, stop smoking and reduce stress to lower chances of having another blocked artery. A health care provider may also prescribe medicine to help lower cholesterol.

The study was published in January in the Journal of the American College of Cardiology: Cardiovascular Interventions.

Review Date: 
January 24, 2014
Last Updated:
January 27, 2014