Coronary flow analysis during autoperfusion angioplasty

Area of Science:

• Cardiology
• Interventional Cardiology
• Medical Devices

Background:

• Autoperfusion balloons aim to protect the myocardium during angioplasty by utilizing aortic pressure for distal perfusion.
• While effective in vitro, the in vivo distal blood flow provided by these devices remains largely unquantified.
• These devices are particularly recommended for high-risk patients susceptible to hemodynamic collapse during balloon inflation.

Purpose of the Study:

• To quantify distal coronary blood flow during percutaneous transluminal coronary angioplasty (PTCA) using autoperfusion balloons.
• To assess the adequacy of distal perfusion provided by autoperfusion balloons in vivo.

Main Methods:

• Coronary flow velocity was measured using Doppler guidewires in eight patients undergoing elective PTCA.
• Coronary blood flow was calculated by multiplying luminal area with average peak flow velocity.
• Coronary flow velocity reserve was assessed before and after angioplasty via intracoronary adenosine injection.

Main Results:

• Distal coronary blood flow during balloon inflation was 19 +/- 3.8 ml/min, representing 56% of pre-angioplasty flow (35 ml/min).
• Four patients experienced electrocardiographic changes, and three reported chest pain during balloon inflation.
• Coronary flow velocity reserve significantly increased post-angioplasty (1.3 to 2.2, P < 0.001).

Conclusions:

• Autoperfusion balloons deliver insufficient distal coronary blood flow during PTCA, especially in high-risk patients.
• The measured coronary blood flow during angioplasty was 56% of the pre-procedure baseline.
• For high-risk patients requiring adequate perfusion, active coronary or circulatory support devices are advised.