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Published on: November 24, 2014
False Positive Transit Time Flowmetry Graft Failure in Multivessel Coronary Spasm following Off-Pump Coronary Artery
George Kassimis1, George Krasopoulos2
1Cardiology Department, Gloucestershire Hospitals NHS Foundation Trust, Cheltenham, UK.
Insights
Intraoperative Transit Time Flowmetry (TTF) can be unreliable after coronary artery bypass grafting (CABG) due to coronary spasm. Surgeons must consider coronary spasm as a cause of false-negative TTF results, potentially requiring angiography for diagnosis.
Area of Science:
- Cardiovascular Surgery
- Medical Device Technology
- Diagnostic Imaging
Background:
- Intraoperative Transit Time Flowmetry (TTF) is standard for assessing coronary artery bypass grafting (CABG) graft patency.
- The VeriQ™ system aids in detecting graft imperfections requiring revision.
- TTF is crucial in hemodynamically unstable patients or those unable to wean from cardiopulmonary bypass.
Observation:
- A case report highlights multivessel coronary spasm (CS) occurring post-CABG.
- Coronary spasm interfered with intraoperative TTF parameters, leading to misleading results.
- The VeriQ™ system's ability to distinguish graft failure from CS was compromised.
Findings:
- Coronary spasm can mimic graft failure on TTF assessments.
- False-negative TTF results can occur in the presence of significant coronary spasm post-CABG.
- The VeriQ™ system has limitations in differentiating between graft failure and coronary spasm.
Implications:
- Cardiac surgeons must consider coronary spasm as a differential diagnosis for abnormal TTF findings post-CABG.
- Angiography may be necessary for definitive diagnosis in cases of decreased graft flow despite anastomotic revision and vasodilatory treatment.
- This case underscores the importance of comprehensive diagnostic approaches beyond TTF in specific post-CABG scenarios.
Abstract:
Intraoperative Transit Time Flowmetry is currently recommended to assess graft patency during coronary artery bypass grafting (CABG), especially in presence of haemodynamic instability or inability to wean the patient from cardiopulmonary bypass, new regional wall motion abnormalities, or significant ventricular arrhythmias. The VeriQ™ system is one of the currently available systems, which detects imperfections that may be corrected by graft revision. In this case report, multivessel coronary spasm (CS) post-CABG interferes with these intraoperative parameters misleading initially into false results. Cardiac surgeons should bear in mind the limit of VeriQ in distinguishing between graft failure and CS. Angiography may be considered in patients with decreased graft flow despite revision of anastomosis and vasodilatory treatment for the definitive diagnosis.
