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(Chest. 2004;125:418-424.)
© 2004 American College of Chest Physicians

Novadaq SPY*

Intraoperative Quality Assessment in Off-Pump Coronary Artery Bypass Grafting

Oliver Reuthebuch, MD; Achim Häussler, MD; Michele Genoni, MD; Reza Tavakoli, MD; Dragan Odavic, MD; Alexander Kadner, MD and Marko Turina, MD

* From the Clinic for Cardiovascular Surgery (Drs. Reuthebuch, Häussler, Kadner, and Turina), University Hospital Zürich, and Clinic for Cardiac Surgery (Drs. Genoni, Tavakoli, and Odavic), Zürich, Switzerland.

Correspondence to: Oliver Reuthebuch, MD, Clinic for Cardiovascular Surgery, University Hospital Zürich, Rämistrasse 100, CH-8091 Zürich, Switzerland; e-mail: oliver.reuthebuch{at}chi.usz.ch


   Abstract
TOP
 Abstract
Introduction
 Materials and Methods
 Results
 Discussion
 References
 
Objectives: Off-pump coronary artery bypass grafting may decrease operative morbidity when compared to on-pump bypass grafting; however, it is technically demanding and thus quality control is essential. This study assesses the clinical feasibility of a new, indocyanine green (ICG)-based imaging system (SPY; Novadaq Technologies; Toronto, ON, Canada) to monitor the quality of anastomoses and grafts in off-pump revascularization.

Setting: Thirty-eight consecutive patients undergoing nonemergent coronary artery bypass grafting without the use of extracorporeal circulation at two Swiss cardiac surgery clinics were included. On completion of bypass grafts, the quality of the grafts was assessed using the ICG-based imaging system. The imaging device comprises an 806-nm laser light source that is used to cause ICG to fluoresce and a near infrared-sensitive charged couple device videocamera that is used to capture the fluorescence images. ICG was administered through the central venous line, and images were acquired during the first pass of the ICG through the field of view. Graft flow (qualitative) and the quality of the grafts and anastomoses were assessed intraoperatively.

Results: Between March 2002 and September 2002, a total of 38 patients (26 men and 12 women; mean ± SD age, 64.6 ± 10.5 years; body mass index, 27.1 ± 2.9) underwent surgery and imaging at two institutions. One hundred seven of 124 grafts (45 arteries and 62 veins) were analyzed. Seventeen grafts could not be assessed due to difficulties in positioning. The imaging system was easy to handle, and no adverse reactions to ICG were observed. Four of the 107 grafts imaged required revision (three anastomotic constrictions and one graft dissection). Each imaging sequence required approximately 1.25 to 2.5 mg of ICG. The images were equivalent to angiography without the need for radiographs and catheter insertion. In addition, the course of coronaries that would otherwise be difficult to locate in obese patients could be detected using the imaging system. Biochemical and ECG data demonstrated an absence of intraoperative or postoperative myocardial damage, and no liver enzyme elevation or renal dysfunction.

Conclusions: This study supports the clinical utility of a ICG-based imaging system for the assessment of the quality of bypass grafts, which appears to be safe and simple to use.

Key Words: angiography • beating heart • cardiac surgery • coronary artery bypass • indocyanine green • minimally invasive


   Introduction
TOP
 Abstract
 Introduction
Materials and Methods
 Results
 Discussion
 References
 
In recent years, off-pump coronary artery bypass grafting (OPCAB) has increased in popularity. Performing coronary revascularization without the need for cardiopulmonary bypass may decrease the perioperative morbidity related to extracorporeal circulation. Potential complications of cardiopulmonary bypass include myocardial infarction, organ failure, unspecific inflammatory response, coagulation disorders, stroke, and psychological distress.1 2

However, OPCAB procedures are technically demanding. Despite having various stabilizers accessible, it still remains challenging to accurately graft bypasses to constantly moving coronaries. Optimal exposure of the target vessel is frequently sacrificed to hemodynamic stability, and intracoronary shunts can injure the endothelium and provoke dissections.3 4 Thus, there is increasing interest and concern related to intraoperative assessment of graft and anastomosis quality.

Although at present the armamentarium of devices for assessing intraoperative bypass function is still expanding, the sensitivity, specificity, handling, and clinical impact of the majority of the methods remains an unresolved issue.5 A new, indocyanine green (ICG)-based imaging system (SPY; Novadaq Technologies; Concord, ON, Canada) may be used not only to assess the quality of grafts and anastomoses, but also to detect or verify the course of the coronaries. The aim of the present study was to assess the clinical feasibility of this technology in OPCAB cases.


   Materials and Methods
TOP
 Abstract
 Introduction
 Materials and Methods
Results
 Discussion
 References
 
Novadaq Technologies SPY System
The technology is based on the fluorescence properties of ICG, a nontoxic dye that has been used in medicine for > 40 years. When illuminated with 806-nm light, ICG fluoresces and emits light at 830 nm. This fluorescent light is captured by a charged couple device videocamera at 30 frames per second and displayed on a computer monitor. After analyzing the sequence, the images are saved to the computer in audio video interleave movie format. Hard copies of individual frames may also be printed on the video printer provided.

The whole system is incorporated into a single mobile cart. The laser, with an output of 2.0 W, is positioned along with the camera and auxiliary near infrared light source at the end of an articulating arm (Fig 1 ). The laser light illuminates an area of 56 cm2 (7.5 cm by 7.5 cm) of the heart. Due to the low power density of the emitted laser energy, there is no tissue warming and no need for safety goggles. During the procedure, the articulating arm is draped with a sterile drape that incorporates an optically transparent window that does not degrade image quality (Novadrape; Novadaq Technologies). At the time of intraoperative (open chest) image acquisition, the camera/laser head is positioned above the area of interest at a distance of approximately 30 cm. The correct position is indicated by means of an automatic distance sensor, thus ensuring that the camera is at the correct focal length. After injecting the ICG (by the anesthetist via the central venous line), activation of the laser and image acquisition to the computer are initiated by means of a single command to the computer. Real-time images are displayed on the computer screen as the ICG passes through the field of view.



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  		Figure 1.. The Novadaq Technologies SPY imaging system: (1) laser/camera unit, (2) monitor, distance control, (3) central processing unit, (4) laser generator.

 
ICG
ICG has been used extensively to determine cardiac output, to measure liver function, and for ophthalmic angiography.6 ICG (IC-Green; Akorn; Buffalo Grove, IL) is a water-soluble tricarbocyanine dye with a peak spectral absorption at 800 to 810 nm when dissolved in blood. It contains < 5% iodide sodium. After IV injection, it is rapidly bound to plasma proteins, thus remaining within the vasculature. ICG is excreted by the liver being secreted unchanged into the bile. Thus, there is no potential for harmful effects on kidney function, which is frequently reduced in patients with coronary heart disease.

Adverse reactions to the clinical use are rare; however, the dye should be used with caution in patients with allergy to iodides. Hypotension or urticarial reactions have been reported in some patients and can be treated with appropriate agents (epinephrine, antihistamines, corticosteroids).

Patient Data
The study was conducted at two Swiss clinics, the University Hospital of Zurich in Zurich, and the Stadtspital Triemli in Zurich. Between March and September of 2002, 38 consecutive patients undergoing nonemergent coronary artery bypass grafting without the use of extracorporeal circulation were included. Exclusion criteria were renal insufficiency (serum creatinine > 100 µmol/L, urea > 12 mmol/L), severe hepatic malfunction (lactate dehydrogenase [LDH] > 420 U/L, aspartate aminotransferase [ASAT] > 52 U/L, alanine aminotransferase [ALAT] > 50 U/L), and a history of allergy to iodide. Postoperative study end points included assessment of cardiac, renal, and hepatic function. Data were collected on body mass index (BMI), time for surgery (in minutes), ventilation time (in hours), stay in ICU (in days), the cardiac enzymes creatinine kinase (CK) and its isoform (CK-MB), troponin-T, and myoglobin, ECG changes (new Q-wave, new loss of R-progression, new ST-segment alterations), serum creatinine, serum urea, LDH, ASAT, and ALAT levels.

Surgical Approach:
In cases of minimal invasive direct coronary artery bypass grafting (MIDCAB), the left internal mammary artery (LIMA) was dissected by means of a robotic telemanipulator (da Vinci; Intuitive Surgical; Sunnyvale, CA). After adjusting the system, the instruments and optic were inserted via three tiny left thoracic incisions. Under single lung ventilation, the course of the LIMA was assessed and the artery robotically skeletonized. After removal of the robotic telemanipulator, a small left anterior thoracotomy was performed, the pericardium incised, and the left anterior descending artery (LAD) stabilized (CardioThoracic Systems; Cupertino, CA). The dissected LIMA was grasped and end-to-side anastomosed to the LAD using a running 7–0 Fumalene suture (Fumedica Germany; Herne, Germany).

In patients requiring more than bypass graft, the left and/or right internal mammary artery (IMA) was conventionally skeletonized via median sternotomy. If feasible, saphenous vein grafts were harvested endoscopically (Karl Storz; Tuttlingen, Germany). Following pericardial opening, proximal vein-to-aorta anastomoses were performed prior to performing the distal anastomoses.

Pericardial traction sutures facilitated the exposure of coronaries, especially of the right coronary artery (RCA) and the circumflex artery (CX). Consecutively, coronaries were stabilized (ESTECH, Danville, CA or Guidant, Indianapolis, IN) and incised. After insertion of intracoronary shunts, grafts were anastomosed with 7–0 or 8–0 Fumalene continuous sutures.

In cases of sequential grafts, the order of performing distal anastomoses depended on the degree of cardiac luxation required: the more the heart had to be rotated to reach the coronary, the later the vessel was grafted. This method resulted in a more stable hemodynamic situation, as well as in an instant and sequential check of the anastomoses.

Intraoperative Imaging
In cases of obese patients, with a considerable amount of epicardial fat, the ICG-based imaging system was used as an aid in locating the course of coronaries (LAD) prior to revascularization. ICG was injected through the central venous line, the camera was positioned over the probable site of the coronary, and videosequences were recorded and analyzed. After identification, the coronary was dissected with a scalpel; in cases of nonidentification, imaging was repeated while varying the amount of dye and/or the position of the camera.

Patency verification with the ICG-based imaging system was performed after each anastomosis. Following the recommendations of Novadaq Technologies (based on animal and clinical experiments), the usual dose of ICG administered through the central venous line is 1.25 to 2.5 mg per image sequence. In patients with > 100 kg body weight, the dose had to be adjusted if the images were too dark (usually 2.5 to 5 mg per patient). Immediately after injection, the laser/camera/recorder unit was activated. The system shut off automatically 30 s later, at which time ICG had washed out of the coronary arteries and cleared through the coronary venous system.

In the present version of the imaging system, no quantitative analysis is available (milliliters per second of blood flow) and so indirect predictors, similar to angiographic techniques, had to be assessed: (1) optical quality of anastomosis, (2) quality of dye flow in grafts/coronaries, and (3) quality of myocardial opacification distal to the anastomosis (run-off). Immediate and rapid run-off of dye as well as extended opacification of the myocardium was used as an indication of good quality of anastomosis, and high intravascular ICG signal was used as an index for good graft quality. As we strongly believe in intraoperative quality control in OPCAB surgery, we additionally measured graft flow with transit-time flowmetry (TTFM) [Medi-Stim AS; Oslo, Norway], a routine procedure in our clinic.


   Results
TOP
 Abstract
 Introduction
 Materials and Methods
 Results
Discussion
 References
 
Between March and September 2002, a total of 38 consecutive patients (26 men and 12 women) with 124 grafts were included in the study. Mean age was 64.6 ± 10.5 years, and mean BMI was 27.1 ± 2.9.

Two patients were operated via a left small thoracotomy (MIDCAB) with a single LIMA-LAD bypass. Thirty-six patients were grafted via median sternotomy with left or bilateral IMA and additional saphenous vein grafts (Table 1 ).


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  		Table 1.. Surgical Technique*

 
In three patients, the course of the LAD was assessed by ICG fluorescence imaging (Fig 2 ). Injection of 2.5 mg of ICG in the central venous line in two patients (BMI, 26.9 ± 0.5) was sufficient to obtain adequate signal to define the course of the LAD. In one patient (BMI, 33.4), imaging had to be repeated with 5 mg of dye in order to adequately visualize the LAD.



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  		Figure 2.. Clinical example 1: coronaries (LAD, arrows) of this obese patient could be detected after injection of ICG.

 
Of 124 grafts, 107 grafts (45 arteries and 62 veins) were assessed by means of the ICG-based imaging system. Seventeen grafts were not amenable to imaging due to posterior location (CX and RCA). Inappropriate angle or invisibility due to overlapping sternal or pericardial edge hindered the correct assessment. In 103 of 107 grafts, imaging demonstrated rapid filling, and emptying, of the grafts with ICG (Fig 3 ). Subsequent evaluation of the time-intensity relation of epicardial opacification showed similar findings. However, direct evaluation of anastomoses was sometimes less accurate due to adjacent tissue (fat, connective tissue, glue) or even suture material that covered part of the anastomosis (Fig 4 ). After digital analysis, it occasionally appeared to be difficult and time-consuming to distinguish these findings from real anastomotic narrowing. As a result of ICG imaging, 4 of 107 grafts were revised. In three cases, this was due to anastomotic constriction. In one case, revision was required due to graft dissection (LIMA; Fig 5 ). After revision, repeat ICG fluorescence imaging demonstrated excellent flow patterns.



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  		Figure 3.. Clinical example 2: single vein graft (arrow) to first obtuse marginal branch. Flow patterns of ICG proved decent quality of anastomosis and graft respectively.

 


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  		Figure 4.. Clinical example 3: single vein graft to first obtuse marginal branch (*) and LIMA graft to LAD (**). Due to epicardial fibrin glue and intramyocardial course of LAD (arrows), direct assessment of anastomosis was impossible.

 


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  		Figure 5.. Clinical example 4: Single vein graft to first obtuse marginal branch (*) and LIMA graft to first diagonal branch (**). No ICG signal in LIMA proved malfunction of graft. Opening of graft revealed proximal dissection.

 
In 97 of 107 grafts, useful images were acquired following injection of only 1.25 mg of ICG; in the remaining 10 grafts, 2.5 mg of ICG per injection were needed to adequately assess the flow patterns. The system is easily set up in 2 to 3 min for each image-sequence acquisition. In total, three operators are needed: the anesthetist to inject the dye, the technician to start recording and analyzing, and the surgeon to position the camera. During the 30 s of recording, it is not possible to move the camera, as safety features incorporated in the device will cause the laser to deactivate. Depending on the total number of recorded images, saving of the data to the hard disk can take several minutes. During this interval the system cannot be used for further image acquisition.

Mean time for surgery was 240 ± 41.4 min, time on ventilator was 16.6 ± 8.4 h, and stay in ICU was 2.1 ± 1.6 days. No acute or long-term side effects of ICG were observed. Liver enzymes as well as renal parameters were always in range compared with preoperative data. They were measured 4 h after surgery and every consecutive day until discharge from hospital (Table 2 ).


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  		Table 2.. Renal and Hepatic Laboratory Parameters*

 
Imaging had no detrimental effects on the myocardium. Postoperative levels of CK, CK-MB, and troponin-T were low, as to be expected following OPCAB procedures (Table 3 ). No ECG signs showing intraoperative or postoperative myocardial infarction as well as postoperative ventricular arrhythmias were observed.


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  		Table 3.. Cardiac Laboratory Parameters*

 

   Discussion
TOP
 Abstract
 Introduction
 Materials and Methods
 Results
 Discussion
References
 
Off-pump myocardial revascularization may decrease operative morbidity when compared with coronary artery bypass grafting using extracorporeal bypass.1 2 However, the technique is highly demanding, and its success depends greatly on the precision and accuracy of the surgeon.

To obtain good short- and long-term results, intraoperative or immediate postoperative quality control of anastomoses and grafts is mandatory. Crude methods, such as palpating the graft or analyzing the ECG for any ST-segment alterations, are far from adequate and may be a reason for early vein graft occlusions of up to 20% or abnormalities in the IMA graft of approximately 20%.7 8 9 Undoubtedly, the appropriate time to revise a problem anastomosis is during the initial operation. Prolonged postoperative ischemia can run a disastrous course with the potential need for emergency catheterization and emergency repeat surgery. To address this need, several techniques have been developed in an attempt to achieve adequate quality control during surgery. Mohr et al10 and Emery et al11 demonstrated the clinical impact of thermal coronary angiography. In a large study population,10 they reported early IMA graft failure in 6.2% of cases. However, to detect potential anastomotic failures, a temperature gradient between graft and heart surface is necessary. This can be easily achieved in on-pump cases, but is not an option in normothermic off-pump surgery.

Angioscopy and intravascular ultrasound, while not requiring contrast agents, are invasive and complex methods. They provide an anatomic picture of the anastomosis or graft, but cannot quantify flow. Intraoperative angioscopy of single vein graft anastomoses showed intimal lesions, flaps, or thrombi in up to 25% of the studied grafts. In addition, although the evaluation of vein grafts is feasible, it is not possible to evaluate IMA grafts.5

TTFM has been reported to be an appropriate means for intraoperative graft assessment.12 To correctly read and understand the findings, the pulsatility index, flow curves, the ratio of peak diastolic flow to peak systolic flow, as well as mean flow values have to be meticulously analyzed. Therefore, the flowmeter should always be coupled with an ECG, the probes have to fit perfectly around the skeletonized graft, and aqueous gel should improve the contact. However, the usefulness of TTFM in terms of detecting less critical stenoses remains uncertain. Cerrito et al13 failed to detect a < 50% narrowing of the anastomosis despite making use of a neural network pattern recognition routine in an attempt to improve the predictive capability of this modality. In addition, with TTFM it is not possible to determine the course of coronaries, which in cases of obese patients or in redo cases can be very advantageous.

Contrast radiograph angiography remains the "gold standard" for assessment of coronary artery bypass grafts. In several studies, Izzat and coauthors14 demonstrated the importance and accuracy of intraoperative angiography. In 24 consecutive patients, they assessed graft patency, anastomosis quality, and distal run-off; grafts were revised in 8% of the patients as a result of these findings.14 However, it remains an invasive, potentially risky, and intraoperative cumbersome technique for intraoperative use.15 In addition, there are several hazards associated with the use of ionizing radiation.15

Based on the clinical benefit of intraoperative angiography, Novadaq Technologies has recently developed a novel technique to assess anastomotic and graft quality. Based on the fluorescence properties of ICG, this new technology replaces radiopaque contrast media with ICG and x-ray radiation with laser light. These have been combined with a videocamera sensitive to near infrared light, and digital image processing technology to produce an intraoperative visualization system that may be considered to be clinically safe, accurate, simple to use, and thus an alternative to radiographic angiography.

ICG is a nontoxic dye that has been in clinical use for 40 years. It has been used extensively to determine cardiac output, to measure liver function, and for ophthalmic angiography.6 16 17 Due to the low incidence of adverse reactions, the clinical use of ICG is regarded as very safe. Carski18 reported four adverse reactions observed in a series of 240,000 administered doses. Benya et al19 published a literature review covering 34 years of clinical use of ICG. Only 17 reactions were reported, 7 in patients with severe renal insufficiency.19 One additional case of shock was reported in Japan in a patient receiving chronic hemodialysis.20

In the present study, we did not observe any adverse reaction either intraoperatively or postoperatively. In addition to the intrinsic safety of ICG, the present application may benefit from the very low dose of ICG (1.25 to 2.5 mg per patient per injection), which we had to inject, compared to 0.5 mg/kg of body weight administered in liver function tests. We did not observe any liver enzyme elevation (ASAT, ALAT, LDH), nor did we encounter any renal dysfunction expressed as elevated serum creatinine or urea.

In OPCAB cases, the dye could be detected in the grafts 2 s following intravenous injection. Analogous to angiographic procedures, we analyzed the sequences with regard to flow patterns in the grafts as well as direct evaluation of the anastomosis. However, 17 could not be assessed due to inappropriate angle between camera and coronary or due to overlapping sternum or pericardium. With a smaller camera/laser unit, this problem possibly could be solved.

In 4 of 107 bypass grafts, we detected irregularities (anastomotic narrowing, dissection) that had to be revised. After revision, subsequent reimaging confirmed patency. With this technique, a 100% on-table patency rate seems possible. Postoperative measurement of myocardial enzymes (CK, CK-MB, troponin) and ECG analysis did not reveal any unexpected changes. As we have learned in OPCAB procedures, enzymatic levels are low when the operation is performed carefully and successfully. The present findings of low circulating myocardial enzyme levels lends indirect support to the conclusion that intraoperative evaluation using the ICG-based imaging system was correct and the interpretation of results accurate. Flow measurement using the TTFM device further confirmed these conclusions. However, it remains difficult to compare quantitative (TTFM) with qualitative (Novadaq Technologies) data. This will be the subject of a subsequent study.

Set-up and clinical usage of the ICG-based imaging system is simple. No further IV lines or catheters are necessary in order to acquire images. The chest remains open when graft patency is confirmed, and so there is no reopening necessary in case of irregularities. Draping and adjustment of the articulating arm supporting the laser/camera unit is simple.

Thirty-second sequences are long enough to analyze graft flow, anastomotic site, and run-off of ICG. However, quantitative flow measurement and curve analysis is not yet available but is under development.

In conclusion, this study emphasizes the need for intraoperative quality assessment in OPCAB surgery. The ICG-based imaging system is a convincing tool that competes with radiographic angiography, the "gold standard" for assessment of graft patency. There are very few anticipated side effects of the technique, yet the quality of images is striking. With the future implementation of quantitative flow measurement, a powerful technology will be available to surgeons.


   Footnotes
 
Abbreviations: ALAT = alanine aminotransferase; ASAT = aspartate aminotransferase; BMI = body mass index; CK = creatinine kinase; CX = circumflex artery; ICG = indocyanine green; IMA = internal mammary artery; LAD = left anterior descending artery; LDH = lactate dehydrogenase; LIMA = left internal mammary artery; MIDCAB = minimal invasive direct coronary artery bypass grafting; OPCAB = off-pump coronary artery bypass grafting; RCA = right coronary artery; TTFM = transit-time flowmetry

Received for publication March 18, 2003. Accepted for publication September 10, 2003.


   References
TOP
 Abstract
 Introduction
 Materials and Methods
 Results
 Discussion
 References
 

  1. Borst, C, Grundemann, PF (1999) Minimally invasive coronary artery bypass grafting: an experimental perspective. Circulation 99,1400-1403[Free Full Text]
  2. Scott, NA, Knight, JL, Bidstrup, BP, et al Systematic review of beating heart surgery with the Octopus® Tissue Stabilizer. Eur J Cardiothorac Surg 2002;21,804-817[Abstract/Free Full Text]
  3. Ngaage, DL Tolerance of haemodynamic changes during beating heart coronary surgery. Eur J Cardiothorac Surg 2001;20,214-215[Free Full Text]
  4. Perrault, LP, Nickner, C, Desjardins, N Effects of coronary endothelial function of the Cohn stabilizer for beating heart bypass operations. Ann Thorac Surg 2000;70,1111-1114[Abstract/Free Full Text]
  5. Falk, V, Walther, T, Philippi, A, et al Thermal coronary angiography (TCA) for intraoperative patency control of arterial and saphenous vein coronary artery bypass grafts: results in 370 patients. J Cardiothorac Surg 1995;10,147-160
  6. Brody, DH, Leichter, L Clearance tests of liver function. Med Clin North Am 1979;63,621-630[ISI][Medline]
  7. Koenig, SC, VanHimbergen, DJ, Jaber, SF, et al Spectral analysis of graft flow for anastomotic error detection in off-pump CABG. Eur J Cardiothorac Surg 1999;16,S83-S87[Abstract/Free Full Text]
  8. Grondin, CM, Campeau, L, Thornton, JC, et al Coronary artery bypass grafting with saphenous vein. Circulation 1989;79,I24-I29[Medline]
  9. Schaff, HV, Cable, DG, Rihal, CS, et al Minimal thoracotomy for coronary artery bypass: value of immediate postprocedure graft angiography [abstract].Circulation 1996;94(suppl),51
  10. Mohr, FW, Matloff, J, Grundfest, W, et al Thermal coronary angiography: a method for assessing graft patency and coronary anatomy in coronary bypass surgery. Ann Thorac Surg 1989;47,441-449[Abstract]
  11. Emery, RW, Emery, AM, Flavin, TF, et al Revascularization using angioplasty and minimally invasive techniques documented by thermal imaging. Ann Thorac Surg 1996;62,591-593[Abstract/Free Full Text]
  12. Laustsen, J, Pedersen, EM, Terp, K, et al Validation of a new transit time ultrasound flowmeter in man. Eur J Vasc Endovasc Surg 1996;12,91-96[CrossRef][ISI][Medline]
  13. Cerrito, PB, Koenig, SC, VanHimbergen, DJ, et al Neural network pattern recognition analysis of graft flow characteristics improves intra-operative anastomotic error detection in minimally invasive CABG. Eur J Cardiothorac Surg 1999;16,88-93[Abstract/Free Full Text]
  14. Izzat, MB, Khaw, KS, Atassi, W, et al Routine intraoperative angiography improves the early patency of coronary grafts performed on the beating heart. Chest 1999;115,987-990[CrossRef][ISI][Medline]
  15. Jaber, SF, Koenig, SC, BhaskerRao, B, et al Role of graft flow measurement technique in anastomotic quality assessment in minimally invasive CABG. Ann Thorac Surg 1998;66,1087-1092[Abstract/Free Full Text]
  16. Kawai, C, Yamashita, K, Takatsu, T Measurement of cardiac output using indocyanine green and its clinical application. Saishin Igaku 1968;23,1955-1965[Medline]
  17. Regillo, CD, Benson, WE, Maguire, JI, et al Indocyanine green angiography and occult choroidal neovascularisation. Ophthalmology 1994;101,280-288[ISI][Medline]
  18. Carski, TR Adverse reactions after administration of indocyanine green. JAMA 1978;240,636-639[CrossRef][ISI][Medline]
  19. Benya, R, Quintana, J, Brundage, B Adverse reactions to indocyanine green: a case report and a review of the literature. Cathet Cardiovasc Diagn 1989;17,231-233[ISI][Medline]
  20. Iseki, K, Onoyama, K, Fujimi, S, et al Shock caused by indocyanine green dye in chronic hemodialysis patients [case report]. Clin Nephrol 1980;14,210[ISI][Medline]



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