A patient experience study is recommended to better understand the general effect on patients of having an invasive coronary angiography and the range and severity of side effects and complications from QAngio XA 3D quantitative flow ratio (QAngio QFR), CAAS vessel fractional flow reserve (CAAS vFFR), FFR and instantaneous wave-free ratio.
Further research is recommended on test failure rates of QAngio QFR and CAAS vFFR and how these affect clinical decision making for revascularisation in clinical practice.
Outcome studies are needed to understand the clinical benefit of using QAngio QFR and CAAS vFFR (see section 4.8). These include rates of major adverse cardiovascular events, mortality and EQ-5D data to assess the effect on quality of life.
More diagnostic accuracy studies are needed for CAAS vFFR against an appropriate reference standard.