Feature | March 27, 2012

Study Shows Significant Mismatch Between Angiography, FFR Evaluation

The hemodynamic flow effect of a plaque rupture, as detected by FFR.

March 24, 2012 Coronary angiography is unable to accurately predict the severity of vessel narrowing, suggesting fractional flow reserve (FFR) functional tests should be added to help determine if a patient needs revascularization. This was according to research presented from the IRIS FFR-DEFER trial at the American College of Cardiology's (ACC) 61st Annual Scientific Session this week in Chicago. 

Seeking to improve physicians’ decision-making process when determining if a patient needs revascularization, a South Korean research team compared two different methods of evaluating arterial narrowing: coronary angiography and FFR. Currently, coronary angiography is commonly used to determine the need for revascularization, while FFR is included in practice guidelines but less frequently utilized. FFR uses an catheter probe to measure the level of blood flow before and after a stenotic lesion to determine how much the narrowing is affecting arterial function.

Specifically, the team wanted to determine why there is often a discrepancy, called a “visual-functional mismatch,” between the findings of these tests when performed on the same vessel.

“There are often notable discrepancies between the angiographic diameter stenosis and the physiologic significance of the lesion,” said lead investigator Seung-Jung Park, M.D., Ph.D., professor of medicine at Asan Medical Center in Seoul, South Korea. 

“We conducted the study to provide a comprehensive understanding of the factors responsible for this ‘visual-functional mismatch,’ which we believed would be helpful to overcome interventionalists’ excessive preoccupation with using angiography to decide whether to treat or not to treat,” he said. 

The researchers enrolled 1,000 patients with 1,129 lesions between November 2009 and June 2011 at a single center in Seoul, South Korea. Sixty-three patients had left main coronary artery (LMCA) lesions (a more complex type of narrowing; number of lesions=63), while 937 patients had non-LMCA lesions (number of lesions=1,066). The researchers completed three tests on each lesion: coronary angiography, FFR and intravascular ultrasound. They then examined the occurrence of visual-functional mismatch and analyzed the factors that led to the discrepancies between coronary angiography and FFR. 

They found that among patients with non-LMCA (less complex) lesions, there were 605 lesions in which coronary angiography showed that the vessel had narrowed by more than 50 percent (suggesting that the heart may not be getting enough oxygen, a condition called “myocardial ischemia”). Of these lesions, 343 (57 percent) showed a FFR of greater than or equal to 0.80 (no more than a 20 percent reduction in blood flow, suggesting that ischemia was unlikely), resulting in a visual-functional mismatch. 

Conversely, among the 461 non-LMCA lesions with less than or equal to 50 percent vessel narrowing (suggesting that ischemia was unlikely), 75 (16 percent) had an FFR of less than 0.80 (more than a 20 percent reduction in blood flow, suggesting that ischemia was likely), resulting in a “reverse” visual-functional mismatch. 

In the LMCA group, mismatch was seen in 8 lesions (35 percent). Reverse mismatch was seen in 16 lesions (40 percent).  

Using statistical analysis and intravascular ultrasound (IVUS), the researchers determined several factors that were predictors of mismatch, including: older patient age (adjusted odds ratio [AOR] 1.04, p<0.001), non-left anterior descending artery location (AOR 3, p<0.001), the absence of plaque rupture (AOR 2.6, p=0.004), short lesion length (AOR 1.03, p<0.001), a large minimal lumen cross-sectional area (AOR 2, p=0.001), a smaller plaque burden (AOR 1.05, p<0.001) and a greater minimal lumen diameter (AOR 1.09, p=0.040). 

The predictors of reverse mismatch included younger age (AOR 1.04, p=0.003), left anterior descending artery location (AOR 5.4, p<0.001), the presence of plaque rupture (AOR 3.2, p=0.011), smaller minimal lumen cross-sectional area (AOR 2.9, p<0.001) and larger plaque burden (AOR 1.03, p=0.027). 

According to the researchers, the results showed that discrepancies between the two tests were caused by clinical and lesion-specific factors that are often unable to be identified from coronary angiography alone. They concluded that coronary angiography could not accurately predict the functional results of FFR and that FFR should be included in the assessment process before cardiac specialists make decisions about revascularization.

For more information: www.acc.org

Related Content

Intact Vascular, TOBA clinical study, one-year results, Tack Endovascular System, Journal of Vascular Surgery
News | Peripheral Arterial Disease (PAD)| August 24, 2016
Intact Vascular Inc. announced that the one-year results from its Tack Optimized Balloon Angioplasty (TOBA) clinical...
Technavio report, renal denervation devices, 2015
News | Renal Denervation| August 23, 2016
August 23, 2016 — Technavio analysts forecast the global...
Jason Burdick, injectable hydrogels, heart failure, heart attack, American Chemical Society

Compared to other types of hydrogels being developed (left), a new hydrogel (right) can form crosslinks after injection into the heart, making the material stiffer and longer-lasting. Image courtesy of American Chemical Society.

News | Heart Failure| August 23, 2016
August 23, 2016 — During a heart attack, clots or narrowed arteries block blood flow, harming or killing cells within
News | Peripheral Arterial Disease (PAD)| August 22, 2016
Avinger Inc. recently announced the closing of its previously announced public offering of 9,857,800 shares of Avinger’...
DMC Heart Hospital, Detroit Medical Center, complex percutaneous intervention education course, PCI, cath lab training
News | Cath Lab| August 22, 2016
The Detroit Medical Center (DMC) Heart Hospital recently completed a Complex Percutaneous Intervention education course...
atomic bombs, radiation exposure, long-term health effects, Bertrand Jordan, study
News | Radiation Dose Management| August 19, 2016
The detonation of atomic bombs over the Japanese cities of Hiroshima and Nagasaki in August 1945 resulted in horrific...
TAILOR-PCI study, antiplatelet medication, genotype, NHLBI grant
News | Antiplatelet and Anticoagulation Therapies| August 18, 2016
Researchers at the Peter Munk Cardiac Centre, Toronto, and at Mayo Clinic are leading the Tailored Antiplatelet Therapy...
Covidien, Medtronic, TurboHawk, Atherectomy system

The Medtronic TurboHawk atherectomy system. 

Feature | Atherectomy Devices| August 18, 2016 | Dave Fornell
Due to poor outcomes from percutaneous transluminal angioplasty (PTA) ballooning of vessels alone, or of stenting in
Sapien III, Sapien 3, PARTNER III, FDA approval, expanded indication, intermediate risk patients

The Sapien 3 valve has a skirt of fabric at its base that has significantly reduced issues of paravalvular leak, which was an issue with the first generation Sapien device. 

Feature | Heart Valve Technology| August 18, 2016 | Dave Fornell
August 18, 2016 — The U.S.
Corindus Corpath, Acist Medical RXi and CVi, Fairview Southdale Hospital, Minnesota, cath lab
News | Cath Lab| August 17, 2016
Corindus Vascular Robotics Inc. and Acist Medical Systems Inc. are providing Fairview Southdale Hospital, Edina, Minn...
Overlay Init