Publications

Abstract: Cardiac ischemia after coronary artery bypass grafting is often caused by graft occlusion. Short- and long-term graft patency is related to the quality of the surgical technique during harvesting and anastomosis. Transit time flow measurement is a recognized technique for the quality control of grafts but may not rule out structural abnormalities in the conduits, which can cause graft occlusion. This article reports on two cases of suspected intra-arterial dissection of the left internal mammary artery despite satisfactory flow measurements. Routine ultrasound scanning of arterial conduits is helpful in distinguishing dissection and hematoma in the graft conduits.

Purpose of review: The coronary artery bypass graft (CABG) operation is one of the few remaining operations/interventions on diseased arteries that are not routinely verified during or immediately after the procedure. This review answers the ‘how’, ‘when’ and ‘why’ of intraoperative CABG assessment.

Recent findings: More recent than new literature on this topic, is the increased interest in quality assurance of CABG. This is most likely due to reports in the last 5 years suggesting CABG superiority to percutaneous coronary intervention (PCI) for improved mid-term and long-term outcomes; for example, for patients with diabetes mellitus (Freedom Trial by Farkouh in 2012), and for patients with SYNTAX score  33 (SYNTAX Trial by Mohr in 2013). Possibly CABG is re-emerging from the era-of-better-and-better-stents and is now deemed worthy of improvement. Read more...

This case report is based on the observations of a 66 year old man with 3 vessel disease who underwent off-pump coronary artery bypass grafting including a LIMA-LAD procedure. Routinely use of TTFM showed flow 10 ml/min, pulsatility index of 2, diastolic filling of 65% and an acceptable flow curve. The flow measurement was lower than expected and epicardial imaging was done by using a 15-Mhz high frequency ultrasound probe. Read more...

The evaluation of native coronary arteries in cardiac surgery represents a useful tool to detect coronary artery stenosis, identify the target artery, and choose the best anastomotic site. Intraoperative graft assessment is a fundamental step of coronary artery bypass grafting. It is able to reduce graft failure related to technical error, improving both short- and long-term outcome of patients submitted to surgical myocardial revascularization. Herein procedures of graft assessment are described, reporting their strengths and limitations.

Transit-time flow measurement (TTFM) is a reliable method to check the graft function intraoperatively in coronary surgery. The given parameters are Mean Graft Flow (MGF); Pulsatility Index (PI) and Insufficiency Ratio (%BF).

Some cutoffs of these parameters have been identified as predictors for unfair 1-y clinical outcome: mean graft flow (MGF) less than 20 ml/min and high pulsatility index greater than 5.

Other cutoffs have been found as related to postoperative angiography: MGF 15 ml/min or less and pulsatility index at least 3 (sensitivity 94%; specificity 61%); MGF less than 15 ml/min and pulsatility index greater than 3 for left coronary artery.

Pulsatility index greater than 5 for right coronary artery (sensitivity 96%; specificity 77%); MGF 15 ml/min or less and pulsatility index at least 5.1 left coronary artery (sensitivity 98%; specificity 26%).

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