The Oxford Optimisation of PCI Study (OXOPT-PCI Study) (OXOPT-PCI)

The OxOPT-PCI study addresses patients with coronary artery disease who are referred to the John Radcliffe Hospital because of the need for treatment with an intra-coronary stent (metal scaffold) for clinical reasons. Although, this has become a highly standardised procedure it is still challenging for the clinician to assess the final success of this procedure at the end of intervention with conventional methods. This shortcoming can potentially translate into a worse clinical outcome for approximately 10 percent of all patients treated with an intra-coronary stent for this type of disease. This study (OxOPT-PCI) investigates if the use of blood flow measurements (namely measurement of fractional flow reserve (FFR)) and intravascular imaging (namely optical coherence tomography (OCT)) after the implantation of a stent can improve the treatment result for these patients. Both, FFR and OCT are being used already in daily clinical routing but their usefulness especially in combination is not clear. In order to standardise the optimisation procedure we developed a specific algorithm to make sure that all patients receive the same optimisation measures based on the assessment of FFR and OCT. The benefit of this specific optimisation algorithm will be assessed by measuring 1) indices of coronary blood flow, 2) intravascular imaging at the end of the procedure, and 3) by contacting the patients 12 months after stenting to verify the clinical mid-term success.

After administration of intracoronary nitrates, FFR was measured under maximal hyperaemia, using intravenous adenosine (140 mg kg-1 min-1) as the ratio between distal coronary pressure (Pd) and aortic pressure (Pa)

Defined as presence of a linear rim of tissue ≥200 μm in width and with clear separation from the vessel wall, or underlying plaque <5 mm from stent edges

Defined as reference lumen area <4.5 mm2, with significant residual plaque within 10 mm of stent edges

Defined as tissue prolapsing between stent struts extending inside a circular arc connecting adjacent struts or intraluminal mass ≥500 μm thick with no direct connection to the vessel wall, or highly backscattered luminal protrusion in continuity with the vessel wall, resulting in signal-free shadowing

Inclusion Criteria: participant is willing and able to give informed consent for participation in the study angiogram shows haemodynamically relevant lesion suitable for PCI and suitable for the use of intravascular imaging (OCT) Exclusion Criteria: patients in whom safety or clinical concerns preclude participation ST-segment elevation myocardial infarction presentation with cardiogenic shock revascularization by mean of balloon angioplasty without stenting contraindications to adenosine