Intra-operative quality assessment of coronary artery bypass grafts

Area of Science:

• Cardiovascular Surgery
• Medical Instrumentation
• Surgical Monitoring

Background:

• Early coronary artery bypass graft (CABG) failure can lead to severe complications like myocardial infarction and heart failure.
• Detecting graft failure during surgery is challenging with current methods like visual assessment or palpation.
• Technical issues with graft conduits and anastomoses contribute significantly to early graft failures.

Purpose of the Study:

• To evaluate the accuracy and clinical utility of a transit-time ultrasonic flow measurement system for assessing CABGs.
• To determine if transit-time flow measurements can reliably detect technical errors during CABG surgery.

Main Methods:

• In vitro validation of the transit-time flow system against volumetric measurements across various flow rates.
• Application of the transit-time ultrasonic flow system to 298 CABGs in 125 patients during surgery.
• Analysis of graft flow rate and waveform morphology in relation to target vessel diameter and anastomosis quality.

Main Results:

• The transit-time system demonstrated high accuracy, with no significant differences compared to volumetric measurements in vitro.
• Graft flow rate was found to be proportional to the diameter of the target native vessel.
• Nine technical errors were identified and corrected intraoperatively based on flow measurements and waveform analysis.
• Flow waveform morphology provided crucial insights into anastomosis quality, enabling immediate surgical correction.

Conclusions:

• Transit-time ultrasonic flow measurement is an accurate and valuable tool for assessing CABG patency in real-time.
• This technology facilitates the detection and correction of technical errors during surgery, potentially reducing early graft failure.
• Intraoperative use of transit-time flow measurement can enhance surgical decision-making and improve patient outcomes.