Document Detail


Evaluation of coronary bypass flow with color-Doppler and magnetic resonance imaging techniques: comparison with intraoperative flow measurements.
MedLine Citation:
PMID:  10431861     Owner:  NLM     Status:  MEDLINE    
Abstract/OtherAbstract:
OBJECTIVES: After coronary artery bypass surgery, patency and flow assessment is based on invasive methods such as angiography and intravascular ultrasound or flow wire techniques. The aim of the study was to compare intraoperative transit time flow measurements of coronary bypass grafts with early postoperative color-Doppler and MR-imaging assessment. METHODS: In 22 patients (62+/-8.5 years) undergoing elective coronary bypass surgery the flow was measured in all internal mammary artery grafts (IMA) and saphenous vein grafts using the transit time flow technique. Postoperatively (days 5-7) all patients had a color-Doppler IMA graft assessment followed by a MR-angiography and flow measurement (navigator echo phase contrast technique with and without contrast bolus application) to determine patency and graft flow. RESULTS: Data are expressed as the mean +/- SD). (1) In all patients the left IMA graft to the left anterior descending coronary artery (LAD) could be identified and flow could be assessed with both color-Doppler and MRI. Venous grafts could only be visualized by MRI. The use of an intravenous contrast bolus enhanced the visualization of coronary artery bypass grafts. (2) The mean IMA to LAD flow was 33+/-17 ml/min intraoperatively by transit time and postoperatively 36+/-25 ml/min by MR respectively 66+/-54 ml/min by color-Doppler technique. (3) The systolic/diastolic flow ratio was 0.44+/-0.12 intraoperatively and 0.43+/-0.17 postoperatively by MR respectively 0.67+/-1.0 by color-Doppler. (4) A statistically significant correlation could be demonstrated between intraoperative transit time and postoperative MR flow measurements (r = 0.57; P < 0.04), whereas the correlations to color-Doppler flow were poor. Postoperatively MR and color-Doppler showed a good correlation of systolic/diastolic flow ratio (r = 0.88; P < 0.008). CONCLUSIONS: The color-Doppler method during echocardiography and MR-imaging are useful non-invasive techniques to visualize postoperative IMA grafts for patency assessment. The quantification of IMA flow is still difficult with either technique, but MR flow measurements showed the best correlation to the intraoperatively measured transit time flow. The MR technique is the most promising non-invasive method for postoperative evaluation of coronary bypass grafts, since it allows visualization and reliable flow quantification.
Authors:
B H Walpoth; M F Müller; I Genyk; B Aeschbacher; B Kipfer; U Althaus; T P Carrel
Publication Detail:
Type:  Comparative Study; Journal Article; Research Support, Non-U.S. Gov't    
Journal Detail:
Title:  European journal of cardio-thoracic surgery : official journal of the European Association for Cardio-thoracic Surgery     Volume:  15     ISSN:  1010-7940     ISO Abbreviation:  Eur J Cardiothorac Surg     Publication Date:  1999 Jun 
Date Detail:
Created Date:  1999-08-24     Completed Date:  1999-08-24     Revised Date:  2006-11-15    
Medline Journal Info:
Nlm Unique ID:  8804069     Medline TA:  Eur J Cardiothorac Surg     Country:  ENGLAND    
Other Details:
Languages:  eng     Pagination:  795-802     Citation Subset:  IM    
Affiliation:
Department of Cardiovascular Surgery, Radiology and Cardiology, University Hospital Insel, Bern, Switzerland. beat.walpoth@insel.ch
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MeSH Terms
Descriptor/Qualifier:
Blood Flow Velocity
Contrast Media
Coronary Artery Bypass*
Coronary Circulation*
Humans
Intraoperative Period
Magnetic Resonance Angiography*
Male
Mammary Arteries / physiology,  transplantation,  ultrasonography
Middle Aged
Saphenous Vein / physiology,  transplantation,  ultrasonography
Ultrasonography, Doppler, Color*
Chemical
Reg. No./Substance:
0/Contrast Media

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine


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