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

News | Structural Heart| September 02, 2015
An investigational material known as Bioabsorbable Cardiac Matrix (BCM), designed to prevent cardiac remodeling in...
acute ischemic stroke, larger thrombi retrieval, improved neurological recovery, ESC 2015, MR CLEAN trial, sub-study
Feature | Thrombectomy Devices| September 02, 2015
Retrieval of larger thrombi during intra-arterial treatment (IAT) is associated with improved neurological recovery...
chest pain, triage, emergency department, new rapid assay, Dirk Westermann, BACC study, ESC 2015
News | Blood Testing| September 02, 2015
Emergency department patients with chest pain suggestive of acute myocardial infarction (AMI) can be triaged more...
Pie Medical Imaging, Frost & Sullivan, technology leadership, CAAS, cardiovascular diagnostics

CAAS MRV is part of Pie Medical Imaging's suite of imaging solutions for quantitative cardiovascular diagnosis and treatment planning. - See more at: http://www.itnonline.com/content/pie-medical-imaging-recognized-innovati...

News | Cardiac Imaging| September 01, 2015
Based on its recent analysis of the cardiovascular image management market, Frost & Sullivan recognizes Pie Medical...
Absorb, BVS, bioresorbable stent
News | Stents Bioresorbable| September 01, 2015
September 1, 2015 — A bioresorbable drug-eluting coronary stent showed similar efficacy and safety results compared t
bivalirudin,angiomax
Feature | Antiplatelet and Anticoagulation Therapies| September 01, 2015
September 1, 2015 — Extending treatment with the anticoagulant bivalirudin for at least four hours after completion o
Mitralign, Percutaneous Tricuspid Valve Annuloplasty System

Mitralign's Percutaneous Tricuspid Valve Annuloplasty System uses catheter delivered pledgeted sutures that can be cinched together to change the valve annulus geometry to help eliminate valvular regurgitation. 

News | Heart Valve Repair| August 31, 2015
August 31, 2015 — Mitralign Inc. said the U.S.
biomimics, 3D stent
News | Peripheral Arterial Disease (PAD)| August 28, 2015
August 28, 2015 — PinnacleHealth CardioVascular Institute enrolled the first patient in Pennsylvania and second in th
iFR, FFR, Philips, Volcano
News | Cath Lab| August 28, 2015
August 28, 2015 — Philips Healthcare is showcasing its latest cardiology solutions at the European Society of Cardiol
News | Heart Failure| August 28, 2015
August 28, 2015 — BioControl Medical said it has completed enrollment in its INOVATE-HF (INcrease Of VAgal TonE in He
Overlay Init