Percutaneous coronary intervention (PCI) is a standard treatment strategy for coronary
artery disease (CAD). With the presence of myocardial ischemia, PCI reduces the risks of
death, myocardial infarction (MI), and revascularization compared to medical therapy.
However, the risk of future clinical events remains high, and about 10% of patients
experienced further cardiovascular events after PCI. Facing intermediate coronary lesions
the use of pressure wires is the standar of care, however, limitations in the management
of angiographically intermediate coronary lesions continue to be a challenge for the
interventional cardiologist. The measurement of fractional flow reserve (FFR) to
determine the hemodynamic relevance of coronary stenosis has been shown to be a technique
that improves the prognosis and cost-efficiency of the procedures when compared to visual
angiographic interpretation alone. Due to this evidence, the use of FFR to guide
interventional procedures is a class I recommendation in current clinical practice
guidelines.
Patients with multivessel coronary artery disease are another field in the use of
pressure guiding. In these patients, the use of FFR has demonstrated the reclassification
of the severity of coronary lesions in up to 40% of cases, modifying the number of
functionally significant lesions and making it possible to reorient therapeutic
decisions, avoiding interventional treatment of non-significant lesions and with a better
prognosis.
However, the use of FFR has some limitations such as the use of adenosine due to its
cost, adverse effects (e.g. transient atrioventricular block, angina, headache, etc.) and
time consuming. In addition, the presence of atrioventricular block, asthma or severe
chronic obstructive pulmonary disease are relative contraindications for its use. In this
sense, in recent years new rest indices (iFR, RFR, dPR) and hyperemic indices without
adenosine (cFFR-NTG, Pd/Pa-NTG or cFFR) have been developed , demonstrating an
improvement in terms of outcomes with its use, so they can also be used as a tool to
guide us to plan our strategy. These new indices, particularly the cFFR-NTG, are simpler,
at least as safe and have an excellent correlation with the FFR with adenosine in the
assessment of intermediate coronary lesions.
In recent years, functional assessment after intervention has also been increasingly
implemented, which, like intracoronary imaging, can make us change our attitude and
correlate with the prognosis. The lower implementation of this practice, especially in
multivessel patients, may result from having to lose the position of the wire to check
equalization, difficulty in crossing the wire, wear/breakage of the material after
diagnosis (2-3 vessels), use more time and contrast, etc. These problems could be
reduced, at least partially, with the use of the workhorse coronary guidewire pressure
microcatheter to measure post-PCI functional assessment. Although the usefulness of
post-PCI FFR has been demonstrated, there is no clearly established cut-off value
(0.84-0.96) and it seems that in reality the values are a continuum of risk so that the
higher the value, the better the prognosis . Furthermore, other simpler indices such as
rest or hyperemic indices without adenosine have not been correlated with FFR in
post-PCI.
The purpose of this study is to evaluate the correlation between cFFR-NTG and other
indices taking FFR as a reference in multivessel patients after undergoing intervention.
Establish cut-off points and correlate it with adverse cardiovascular events (MACE) in a
1-year clinical follow-up.