Myocardial infarction

US-based St Jude Medical has reported results from a new multi-centre clinical trial of its Fractional Flow Reserve (FFR) technology in guiding treatment of non-ST segment elevation myocardial infarction (NSTEMI) patients.

NSTEMI is the most common form of acute coronary syndrome and major cause of premature morbidity and mortality worldwide.

The trial showed that use of FFR technology changed the course of treatment for more than one fifth of patients suffering from NSTEMI heart attacks.

Data from the trial also showed that FFR-guided PCI is safe and likely to reduce procedure-related myocardial infarctions in NSTEMI patients over angiography alone.

FFR technology helps physicians more accurately evaluate the severity of blood flow blockages in the coronary arteries and determine the lesions that require treatment.

According to previous clinical trials, the company’s FFR technology can improve patient outcomes and reduce medical costs in patients with stable coronary artery disease (CAD).

University of Glasgow professor of cardiology and imaging and principal investigator of the FAMOUS-NSTEMI clinical trial Dr Colin Berry said: "In patients suffering NSTEMI, traditional diagnostic imaging tools have limited our ability to optimally assess which blockages require revascularisation.

"What we’ve now found is fractional flow reserve technology has additive diagnostic and clinical benefits for NSTEMI patients.

"Physicians can leverage FFR to better assess the need for interventional procedures and more accurately identify lesions that require stenting."

"We need to continue to evaluate the technology’s potential in new segments of patients."

Currently, the company’s PressureWire FFR measurement technology is credited with altering the treatment strategy of about 22% of patients in a 350-patient FAMOUS-NSTEMI trial.

Enrolment in the FAMOUS-NSTEMI trial was carried out in six UK hospitals between October 2011 and May 2013 and those patients had at least one coronary stenosis at least 30% occluded at time of admission for NSTEMI.

The trial also showed a trend toward a reduction in procedure-related myocardial infarction among patients whose therapy was guided by FFR using the PressureWire technology.

St Jude Medical chief medical officer Dr Mark Carlson said: "Using St Jude Medical PressureWire, physicians can leverage FFR to better assess the need for interventional procedures and more accurately identify lesions that require stenting.

"The clinicians leading the FAMOUS-NSTEMI study have now confirmed that a new group of patients can benefit from FFR."

Image: Diagram of a myocardial infarction (2) of the tip of the anterior wall of the heart (an apical infarct) after occlusion (1) of a branch of the left coronary artery (LCA). Photo: courtesy of J Heuser JHeuser.