Single-wire pressure and flow velocity measurement to quantify coronary stenosis hemodynamics and effects of...

Area of Science:

• Cardiovascular Medicine
• Interventional Cardiology
• Biomedical Engineering

Background:

• Limited simultaneous measurements of distal coronary pressure and flow velocity hinder stenosis pressure drop-velocity (DeltaP-v) relationship studies.
• Accurate assessment of coronary stenosis hemodynamics is crucial for effective treatment.

Purpose of the Study:

• To evaluate the utility of a novel dual-sensor guidewire for simultaneous pressure and velocity measurements.
• To assess the pressure drop-velocity (DeltaP-v) relationships before and after percutaneous coronary intervention (PCI).
• To compare the efficacy of DeltaP-v derived indices with traditional hemodynamic measures like FFR and CFVR.

Main Methods:

• A 0.014-inch dual-sensor guidewire was used in 15 coronary lesions.
• Simultaneous pressure and Doppler velocity data were collected after adenosine infusion.
• DeltaP-v relations were constructed pre- and post-PCI.
• Stenosis resistance (h-SRv) and microvascular resistance (h-MRv) were calculated.

Main Results:

• Half of pre-PCI DeltaP-v relations indicated a compliant stenosis, which was resolved post-PCI.
• Stepwise PCI significantly reduced h-SRv, with initial pressure drop reduction and subsequent velocity increase.
• Reduced microvascular resistance (h-MRv) contributed significantly to post-PCI velocity gains.
• h-SRv demonstrated the largest hemodynamic changes post-PCI compared to CFVR and FFR.

Conclusions:

• DeltaP-v relations provide a comprehensive visualization of hemodynamic improvements post-PCI.
• The stenosis resistance index (h-SRv) is a sensitive measure of functional gain after PCI, integrating pressure and velocity data.
• Simultaneous assessment of stenosis and microvascular resistance offers a valuable tool for guiding PCI.