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

New FDA Proposed Rule Alters Informed Consent for Clinical Studies
News | Cardiovascular Clinical Studies | November 19, 2018
The U.S. Food and Drug Administration (FDA) is proposing to add an exception to informed consent requirements for...
A key slide from Elnabawi's presentation, showing cardiac CT plaque evaluations, showing the impact of psoriasis medication on coronary plaques at baseline and one year of treatment. It shows a reversal of vulnerable plaque development. #SCAI, #SCAI2018

A key slide from Elnabawi's presentation, showing cardiac CT plaque evaluations, showing the impact of psoriasis medication on coronary plaques at baseline and one year of treatment. It shows a reversal of vulnerable plaque development.  

Feature | Cardiovascular Clinical Studies | May 14, 2018
May 14, 2018 – New clinical evidance shows common therapy options for psoriasis (PSO), a chronic inflammatory skin di
Intravenous Drug Use is Causing Rise in Heart Valve Infections, Healthcare Costs. #SCAI, #SCAI2018
News | Cardiovascular Clinical Studies | May 14, 2018
May 14, 2018 — The opioid drug epidemic is impacting cardiology, with a new study finding the number of patients hosp
Patient Enrollment Completed in U.S. IDE Study of THERMOCOOL SMARTTOUCH SF Catheter
News | Cardiovascular Clinical Studies | March 15, 2018
March 15, 2018 –  Johnson & Johnson Medical Devices Companies announced today that Biosense Webster, Inc., who wo
Lexington Begins HeartSentry Clinical Trial
News | Cardiovascular Clinical Studies | February 20, 2018
February 20, 2018 – Lexington Biosciences, Inc., a development-stage medical device company, announced the commenceme
Endologix Completes Patient Enrollment in the ELEVATE IDE Clinical Study
News | Cardiovascular Clinical Studies | February 06, 2018
February 6, 2018 – Endologix, a developer and marketer of treatments for aortic disorders, announced the completion o
12-Month Results from Veryan Medical's MIMICS-2 IDE Study Presented at LINC
News | Cardiovascular Clinical Studies | February 01, 2018
February 1, 2018 – Thomas Zeller (Bad Krozingen, Germany) presented the 12-month results from Veryan Medical’s MIMICS
LimFlow Completes U.S. Feasibility Study Enrollment, Receives FDA Device Status
News | Cardiovascular Clinical Studies | February 01, 2018
February 1, 2018 –  LimFlow SA, developer of minimally-inv
ESC 2017 late breaking trial hot line study presentations.
News | Cardiovascular Clinical Studies | September 12, 2017
September 12, 2017 – The European Society of Cardiology (ESC) Congress 2017 includes several Hot Line Late-breaking C
U.K., NHS studies, weekend effect, hospital admission, atrial fibrillation, heart failure
News | Cardiovascular Clinical Studies | June 28, 2016
New research shows patients admitted to National Health Service (NHS) hospitals in the United Kingdom for atrial...
Overlay Init