Low risk with deferred revascularization based on measures of intracoronary physiology

Functional intracoronary measurements with pressure guidewires assess how much a stenosis limits blood flow. They are currently used mainly in patients with coronary stenosis of intermediate severity. However, there is limited evidence on the safety of deferring revascularisation based on functional measurements in this subset of patients. Two recent large randomised clinical trials, DEFINE FLAIR and iFR SWEDEHEART, showed good outcomes in patients with intermediate stenosis undergoing physiology-guided revascularisation but did not report on patients where procedures were deferred.

The new analysis pooled patient-level data for the 4,529 patients enrolled in these two studies and looked at the impact of deferring procedures. Results showed that significantly fewer patients underwent interventions when iFR was used for decision making compared to FFR (50% vs. 45%, p=0.01).

The rate of major adverse cardiovascular events (MACE) was low in the 2,130 patients where myocardial revascularisation was deferred (4.12% with iFR and 4.05% with FFR at one year).

"The findings support the safety of deferring revascularisation based on iFR or FFR," said lead author Javier Escaned, Consultant Interventional Cardiologist at Hospital Clinico San Carlos, Madrid, Spain.

The event rate was higher in deferred patients who had acute coronary syndromes (ACS) than in those with stable coronary disease (SCD) (5.9% vs. 3.6%, p=0.04). Outcomes between ACS and SCD were significantly different when FFR was used for assessment (6.4% in ACS vs. 3.4% in SCD, p=0.049) but the difference was less marked when iFR was used (5.4% in ACS vs. 3.8% in SCD, p=0.37).

"Deferral of myocardial revascularisation was associated with a higher rate of MACE in patients with acute coronary syndromes than in those with stable coronary disease," said Escaned. He added, "The findings support the importance of further research into the physiological evaluation of patients with ACS."

Commenting on the study, Colin Berry, Professor of Cardiology and Imaging, University of Glasgow and Golden Jubilee National Hospital, UK, said, "Congratulations to the investigators! In ACS patients, invasive management reduces the risk of recurrent spontaneous MI and cardiac death, but these data are not reported in this meta-analysis, nor is the use of evidence-based medicines. This information would be helpful to better understand the results for translation to practice."

Provided by PCR