Current developments and future applications of intracoronary hemodynamics

Area of Science:

• Cardiology
• Interventional Cardiology
• Physiology

Background:

• Intracoronary hemodynamic assessment is crucial for evaluating coronary lesion significance.
• Current methods like coronary flow velocity reserve and fractional flow reserve often require adenosine for hyperemia.
• Accurate assessment improves clinical outcomes in patients with coronary artery disease.

Purpose of the Study:

• To review the physiology, clinical trials, and applications of invasive hemodynamic assessments for coronary lesions.
• To compare adenosine-dependent and adenosine-free indices of coronary lesion significance.

Main Methods:

• Utilizing sensor-mounted guidewires for intracoronary measurements.
• Assessing coronary flow velocity reserve (CFVR) and fractional flow reserve (FFR) with adenosine-induced hyperemia.
• Evaluating the instantaneous wave-free ratio (iFR) during a non-hyperemic, wave-free diastolic period.
• Quantifying microvascular resistance using the index of microcirculatory resistance (IMR) with thermodilution.

Main Results:

• CFVR and FFR assess epicardial lesion severity but require pharmacologic hyperemia.
• iFR offers an adenosine-free alternative by leveraging diastolic physiology.
• IMR quantifies microvascular resistance, providing insights beyond epicardial lesions.

Conclusions:

• Invasive hemodynamic assessments are vital for guiding treatment in coronary artery disease.
• Adenosine-free indices like iFR offer practical advantages.
• Understanding these techniques aids in optimizing patient management and clinical outcomes.