News | July 24, 2012

Retrograde Approach to Complete Artery Blockages Boosts Success Rates

Largest U.S. study of specialized CTO procedure recently highlighted

July 24, 2012 — Use of the retrograde approach to revascularizing coronary chronic total occlusions (CTOs) to deliver catheters to the back end of the plug, rather than attacking it head-on, can be far more successful. This was according to research presented during the recent Society of Cardiovascular Angiographic Interventions (SCAI) 2012 Scientific Sessions.

The study is the largest in the United States to examine the safety and effectiveness of a so-called retrograde approach to angioplasty and stenting of CTOs. Using this innovative technique, interventional cardiologists at three medical centers were successful in tunneling through the obstruction, opening the blocked artery and restoring blood flow to the heart in about 80 percent of patients, many of whom had no alternative treatment options.

“Patients with chronic total occlusions experience chest pain, shortness of breath and other disabling symptoms,” said Tesfaldet T. Michael, M.D., a cardiology research fellow at the University of Texas Southwestern Medical Center in Dallas. “When medical therapy fails, percutaneous coronary intervention (PCI) may be the last resort. It really helps patients to have a better quality of life.”

Up to one-third of patients who undergo diagnostic angiography have cholesterol plaque that completely blocks a coronary artery. If they have previously had coronary artery bypass surgery, a surgeon may be reluctant to operate again. Still, only about 10 percent of CTOs are treated with PCI, largely because of the difficulty of getting an angioplasty balloon and stent across the hardened plug from the front end, and the lower success rates when compared to conventional PCI, which involves an artery that is narrowed but not blocked.

“PCI of CTOs is fundamentally different,” said Emmanouil Brilakis, M.D., Ph.D., FSCAI, director of the cardiac cath lab at the Veterans Affairs (VA) North Texas Healthcare System in Dallas. “We can do non-CTOs with a success rate of nearly 100 percent. PCI of CTOs has about a 50 to 70 percent success rate using the antegrade (front-end) approach, even in experienced centers. It is very resource intensive and markedly less successful.”

The retrograde (back-end) approach to CTOs may be more successful because the cholesterol plug tends to be softer, more tapered and easier to cross at its far end. There are several variations of the retrograde technique. In each case, the back-end catheter and wire are moved into position by following a path of alternative arteries known as collaterals, or by being threaded through an existing bypass graft, if the patient has previously had coronary artery bypass surgery.

In the simplest version of retrograde PCI, called the true-to-true technique, a back-end wire is pushed directly through the blockage to the front end. Today, a more common approach is called reverse CART (controlled antegrade and retrograde tracking and dissection). Using this technique, catheters with wires inside are threaded to both the front and back end of the occlusion. The interventional cardiologist then uses the front-end wire to tunnel into the artery wall just below the surface. Inflation of a tiny balloon enlarges the space and breaks through the tissue layer into the inside of the artery where the blockage is. The back-end wire is then advanced into the space created by the balloon. Once the back-end wire has crossed the blockage, inflation of another balloon opens the artery and pushes aside the cholesterol plaque. Stenting may then be done via the front or back end of the plaque, depending on the specifics of each case.

A third option, simply called CART, switches the roles of the front- and back-end wires, with the back-end wire used to accomplish the initial tunneling into the artery wall.

For the study, researchers analyzed data from 401 consecutive patients treated with retrograde CTO interventions at three U.S. hospitals. The procedures were performed at St Joseph’s Hospital in Bellingham, Wash., (led by William Lombardi, M.D., FSCAI); Piedmont Heart Institute in Atlanta (led by Dimitri Karmpaliotis, M.D.); and the VA North Texas Healthcare System in Dallas (led by Brilakis). Half the patients in the study previously had bypass surgery. In 52 percent of cases, the retrograde approach was used after a standard antegrade approach had failed.

The retrograde CTO intervention was successful in 79.3 percent of patients. The true-to-true puncture was used in 47 percent of cases, reverse CART in 41 percent and CART in 12 percent. Sixteen patients (4 percent) experienced major procedural complications, including death in one, heart attack in two, tearing of a bypass graft in two, puncture of an artery in 10, and difficulty removing PCI equipment in one.

“There is a lot of interest among interventionalists to train in CTO interventions,” Brilakis said. “The retrograde technique has a very steep learning curve, but we need many more trained operators in the United States, given the number of patients and the complexity of the procedures. We hope this report stimulates more people to do this.”

For more information:

Related Content

Trial Data Shows Positive Predictive Results for Boston Scientific HeartLogic Heart Failure Diagnostic
News | Heart Failure| October 20, 2017
October 20, 2017 — Boston Scientific announced new data from the Multisensor Chronic Evaluation in Ambulatory Heart F
Cardiovascular Risk Significantly Higher in Women With Fatty Liver Disease
News | Womens Healthcare| October 20, 2017
Nonalcoholic fatty liver disease (NAFLD) is associated with significantly higher risk of subsequent cardiovascular...
Pregnancy-Related Heart Failure Strikes Black Women Twice as Often as Other Races
News | Womens Healthcare| October 19, 2017
African American women were found to be twice as likely to be diagnosed with peripartum cardiomyopathy as compared to...
MRI May Predict Neurological Outcomes for Cardiac Arrest Survivors
News | Sudden Cardiac Arrest| October 18, 2017
Magnetic resonance imaging (MRI)-based measurements of the functional connections in the brain can help predict long-...
Xarelto Significantly Reduces Major Cardioavascular Events in Stable CAD and PAD Patients
News | Pharmaceuticals| October 18, 2017
October 18, 2017 — Results from the pivotal Phase 3 COMPASS study found that the...
First Patient Enrolled in U.S. Arm of ALIVE Pivotal Heart Failure Trial
News | Heart Failure| October 17, 2017
October 17, 2017 — BioVentrix Inc. recently announced enrollment of the first patient in the U.S.
Low Mortality and Stroke Risks Displayed for Minimally Invasive Aortic Valve Replacements
News | Heart Valve Technology| October 11, 2017
An analysis of more than 1,000 minimally invasive aortic valve replacements and more than 400 additional associated...
New Evaluation Sends Low-Risk ER Chest Pain Patients Home Sooner
News | Cardiac Diagnostics| October 10, 2017
A new evaluation to determine whether emergency room patients with chest pain can go home and follow up with their...
Videos | Chronic Total Occlusion (CTO)| October 09, 2017
Bill Lombardi, M.D., director of complex coronary artery interventions at the University of Washington, discusses the
News | Pharmaceuticals| October 04, 2017
October 4, 2017 — MyoKardia Inc.
Overlay Init