Enhancement of flow measurement for graft verification

Background We aimed to evaluate multiple transit-time flow measurements during coronary artery bypass grafting. Methods Transit-time flow measurements were performed first on the arrested heart both with and without a proximal snare on the target coronary artery, second, after weaning from cardiopulmonary bypass, and third, before chest closure. Results Among the 214 grafts considered, 9 (4.2%) were patent and 6 (2.8%) were failing. In the failed grafts, an abnormal transit-time flow was found during the first measurement, in 5 (2.3%) cases with a proximal snare and in one (0.47%) without a snare. In these cases, technical errors with the distal anastomoses were found and immediately corrected. A problem with the proximal anastomosis was found in one graft during the second measurement and corrected right away. Bending due to excessive length was found in 2 (0.93%) grafts during the third measurement, and graft repositioning was performed. The first transit-time flow measurement showed that mean graft flow was significantly decreased with a proximal snare compared to without a proximal snare, throughout the entire coronary territory. Pulsatility index during the first transit-time flow measurement was higher with a proximal snare than without one. Conclusions The 3-time transit-time flow measurement strategy makes it possible to verify and immediately correct technical problems with coronary bypass grafts.

Download Full-text

The Accuracy of Transit Time Flow Measurement in Predicting Graft Patency after Coronary Artery Bypass Grafting

Innovations Technology and Techniques in Cardiothoracic and Vascular Surgery ◽

10.1097/imi.0000000000000021 ◽

2013 ◽

Vol 8 (6) ◽

pp. 416-419 ◽

Cited By ~ 14

Author(s):

Patrick F. Walker ◽

William T. Daniel ◽

Emmanuel Moss ◽

Vinod H. Thourani ◽

Patrick Kilgo ◽

...

Keyword(s):

Coronary Artery ◽

Coronary Artery Bypass Grafting ◽

Transit Time ◽

Pulsatility Index ◽

Flow Measurement ◽

Artery Bypass ◽

Graft Patency ◽

Bypass Grafting ◽

Flow Measurements ◽

Time Flow

Objective Transit time flow measurement (TTFM) is a method used to assess intraoperative blood flow after vascular anastomoses. Angiography represents the criterion standard for the assessment of graft patency after coronary artery bypass grafting (CABG). The purpose of this study was to compare flow measurements from TTFM to diagnostic angiography. Methods From October 9, 2009, to April 30, 2012, a total of 259 patients underwent robotic-assisted CABG procedures at a single institution. Of these, 160 patients had both TTFM and either intraoperative or postoperative angiography of the left internal mammary artery to the left anterior descending coronary artery graft. Transit time flow measurements were obtained after completion of the anastomosis and after administration of protamine before chest closure. Transit time flow measurement assessment included pulsatility index, diastolic fraction, and flow (milliliters per minute). Angiograms were graded according to the Fitzgibbon criteria. The patients were grouped according to angiographic findings, with perfect grafts defined as FitzGibbon A and problematic grafts defined as either Fitzgibbon B or O. Results Overall, there were 152 (95%) of 160 angiographically perfect grafts (FitzGibbon A). Of the eight problematic grafts, five were occluded (Fitzgibbon O) and three had significant flow-limiting lesions (FitzGibbon B). Two patients had intraoperative graft revision after completion angiography, one had redo CABG during the same hospitalization, and five were treated with percutaneous coronary intervention. A significant difference was seen in mean ± SD flow (34.3 ± 16.8 mL/min vs 23.9 ± 12.5 mL/min, P = 0.033) between patent and nonpatent grafts but not in pulsatility index (1.98 ± 0.76 vs 1.65 ± 0.48, P = 0.16) or diastolic fraction (73.5% ± 8.45% vs 70.9% ± 6.15%, P = 0.13). Conclusions Although TTFM can be a useful tool for graft assessment after CABG, false negatives can occur. Angiography remains the criterion standard to assess graft patency and quality of the anastomosis after CABG.

Download Full-text

A randomized comparison of intraoperative indocyanine green angiography and transit-time flow measurement to detect technical errors in coronary bypass grafts

Journal of Thoracic and Cardiovascular Surgery ◽

10.1016/j.jtcvs.2005.09.061 ◽

2006 ◽

Vol 132 (3) ◽

pp. 585-594 ◽

Cited By ~ 84

Author(s):

Nimesh D. Desai ◽

Senri Miwa ◽

David Kodama ◽

Taadaki Koyama ◽

Gideon Cohen ◽

...

Keyword(s):

Indocyanine Green ◽

Transit Time ◽

Flow Measurement ◽

Indocyanine Green Angiography ◽

Coronary Bypass ◽

Bypass Grafts ◽

Technical Errors ◽

Time Flow ◽

Coronary Bypass Grafts

Download Full-text

External Saphenous Vein Support Mesh Does Not Interfere with Transit-Time Flow Measurement on Venous Coronary Bypass Conduit: Clinical Confirmation

Innovations Technology and Techniques in Cardiothoracic and Vascular Surgery ◽

10.1097/imi.0000000000000238 ◽

2016 ◽

Vol 11 (1) ◽

pp. 70-72

Author(s):

Parmeseeven Mootoosamy ◽

Jalal Jolou ◽

Patrick O. Myers ◽

Beat H. Walpoth ◽

Afksendiyos Kalangos ◽

...

Keyword(s):

Coronary Artery ◽

Transit Time ◽

Saphenous Vein ◽

Vein Graft ◽

Saphenous Vein Graft ◽

Artery Bypass ◽

Coronary Bypass ◽

Flow Measurements ◽

Time Flow ◽

The Right

A 65-year-old patient underwent double coronary artery bypass grafting using the left internal thoracic artery on the left anterior descending coronary artery and nitinol alloy mesh [external Saphenous Vein Support (eSVS)]–covered saphenous vein graft to the right posterior descending coronary artery. Transit-time flow measurements (TTFMs) were obtained on meshed and bare parts of the vein graft. There was no difference in TTFM parameters (flow, pulsatility index, and diastolic fraction values) obtained from the eSVS mesh-covered and the uncovered parts of the venous graft. This observation confirms that eSVS mesh does not interfere with TTFM on venous coronary bypass conduits.

Download Full-text

The influence of diabetes mellitus on transit-time flow measurement in coronary artery bypass surgery

The Thoracic and Cardiovascular Surgeon ◽

10.1055/s-0029-1191545 ◽

2009 ◽

Vol 56 (S 01) ◽

Author(s):

DC Reineke ◽

FF Immer ◽

D Bircher ◽

L Englberger ◽

A Kadner ◽

...

Keyword(s):

Diabetes Mellitus ◽

Coronary Artery ◽

Coronary Artery Bypass ◽

Transit Time ◽

Flow Measurement ◽

Coronary Artery Bypass Surgery ◽

Bypass Surgery ◽

Artery Bypass ◽

Time Flow

Download Full-text

Roles of Transit-Time Flow Measurement for Coronary Artery Bypass Surgery

The Thoracic and Cardiovascular Surgeon ◽

10.1055/s-0037-1618575 ◽

2018 ◽

Vol 66 (06) ◽

pp. 426-433 ◽

Cited By ~ 6

Author(s):

Yasushi Takagi ◽

Yoshiyuki Takami

Keyword(s):

Coronary Artery ◽

Coronary Artery Bypass ◽

Transit Time ◽

Graft Failure ◽

Flow Measurement ◽

Coronary Artery Bypass Surgery ◽

Coronary Circulation ◽

Artery Bypass ◽

Flow Characteristics ◽

Time Flow

AbstractTransit-time flow measurement (TTFM) has been increasingly applied to detect graft failure during coronary artery bypass grafting (CABG), because TTFM is less invasive, more reproducible, and less time consuming. Many authors have attempted to validate TTFM and to gain the clear cutoff values and algorithm in TTFM to predict graft failure. The TTFM technology has also been shown to be a useful tool to investigate CABG graft flow characteristics and coronary circulation physiology. It is important to recognize the practical roles of TTFM in the cardiac operating room by review and summarize the literatures.

Download Full-text

Intraoperative Fluorescence Imaging after Transit-Time Flow Measurement during Coronary Artery Bypass Grafting

Innovations Technology and Techniques in Cardiothoracic and Vascular Surgery ◽

10.1177/155698451200700611 ◽

2012 ◽

Vol 7 (6) ◽

pp. 435-440 ◽

Cited By ~ 5

Author(s):

Satoshi Kuroyanagi ◽

Tohru Asai ◽

Tomoaki Suzuki

Keyword(s):

Coronary Artery ◽

Transit Time ◽

Flow Measurement ◽

Artery Bypass ◽

Delayed Enhancement ◽

The Other ◽

Bypass Grafting ◽

Time Flow ◽

Intraoperative Fluorescence Imaging ◽

Intraoperative Fluorescence

Objective This report describes the complementary use of transit-time flow measurement (TTFM) and intraoperative fluorescence imaging (IFI) during off-pump coronary artery bypass grafting (OPCAB) and compares their results with those of subsequent coronary angiography. Methods The subjects were 159 OPCAB patients, with a total of 435 grafts at a single center between April 2009 and November 2011. During surgery, all grafts were assessed initially by both TTFM and IFI. Transit-time flow measurement was used for screening grafts for possible revision, then IFI was applied to check patency. For IFI, indocyanine green was injected into the superior vena cava, then the presence and timing of fluorescent enhancement were monitored in coronary and graft vessels. Results Twelve grafts were revised after poor TTFM scores. Despite some poor TTFM scores even after revision, subsequent IFI showed that all grafts were enhanced. However, two grafts showed delayed enhancement. In one internal thoracic artery (ITA), delay was caused by competitive flow from a mildly stenotic native coronary artery. The other delayed-enhancement ITA was revised. Reanastomosis was constructed with shorter ITA at the larger lumen size. After about 1 week, all patients underwent coronary angiography (plain angiography for 31, computed tomography angiography for 128). These demonstrated that all 385 arterial grafts, and 48 out of 50 venous grafts, were patent. Conclusions Our OPCAB series using TTFM and IFI achieve extremely high graft patency in the early graft assessments. “Delayed enhancement” of one ITA in comparison with the other suggested either native competitive flow or a bypass graft problem.

Download Full-text