Beneficial impact of aorto-coronary graft markers on post-operative angiography

Coronary Artery Bypass: Review of Surgical Techniques and Impact on Long-Term Revascularization Outcomes

Coronary revascularization for multivessel disease remains a common and costly source of hospitalizations in the United States. Surgical techniques influence outcomes for coronary bypass and also affect the need for percutaneous coronary intervention in the future. As more radial access has been used for coronary angiography, consideration for use of the radial artery as a surgical conduit remains unclear. Saphenous vein grafts are commonly used for coronary bypass, however long-term patency remains suboptimal, and is also associated with a higher risk of adverse events with percutaneous coronary intervention. Thus, understanding the interplay between coronary bypass techniques and percutaneous coronary intervention has become increasingly important.

Surgically placed radiopaque markers: Proof-of-concept of a novel technique to facilitate percutaneous interventions in neonates and infants

OBJECTIVES

Aim of this study was to evaluate feasibility and benefit of self-designed, radiopaque markers as a novel technique in neonates and infants with shunt- or duct-dependent lesions.

BACKGROUND

Surgically placed radiopaque markers have the potential to facilitate postoperative percutaneous interventions.

METHODS

All consecutive children with surgically placed radiopaque markers involving systemic-to-pulmonary artery connections or arterial ducts in the context of hybrid palliation and subsequent cardiac catheterization between January 2013 and March 2019 were included in this analysis. Our primary endpoint was our concept's feasibility, which we defined as a combination of surgical feasibility and the percutaneous intervention's success. Secondary endpoint was the rate of complications resulting from the surgical procedure or during catheterization.

RESULTS

Radiopaque markers that reveal the proximal entry of a surgical shunt or the arterial duct proved to be a feasible and beneficial approach in 25 postoperative catheterizations. The markers' high accuracy enabled easy probing and proper stent positioning in 13 neonates with a median age and weight of 121 days (range 9-356) and 4.7 kg (1.6-9.4) at the intervention. No procedural complications or unanticipated events associated with the radiopaque marker occurred. The markers were never lost, never migrated, and caused no local obstructive lesion. Surgical removal was straightforward in all patients.

CONCLUSIONS

Radiopaque markers are a promising and refined technique to substantially facilitate target vessel access and enabling the accurate positioning of stents during postoperative percutaneous procedures.

Impact of proximal radiopaque coronary bypass graft markers on postbypass surgery coronary angiography

BACKGROUND

Implantation of radiopaque bypass graft markers during coronary artery bypass surgery (CABG) has the potential of facilitating subsequent coronary angiography. This study sought to investigate the impact of proximal coronary bypass graft markers on angiographic outcomes during subsequent coronary angiography in a large cohort.

METHODS AND RESULTS

Between 2005 and 2016, we enrolled 1378 patients (331 with and 1047 without bypass graft markers) with a history of CABG who underwent their first subsequent coronary angiography at our institution. Primary endpoints were radiation time and absolute amount of contrast media used. In unadjusted analyses, radiation time, duration of angiography, dose area product, and the amount of contrast agent were significantly lower in patients with proximal bypass graft markers (P < .001). After full adjustment, proximal coronary bypass graft markers remained a significant predictor for less radiation time and a lower consumption of contrast agent but not for dose area product, which was mainly associated with body mass index and sex. Bypass graft markers were not associated with a lower graft patency.

CONCLUSIONS

Radiopaque coronary bypass graft markers can improve the detection of bypass grafts during subsequent coronary angiography and are associated with a lower radiation time and less consumption of contrast agent. Thus, this easy and cost-efficient technique might significantly reduce the risk of coronary angiography after CABG.

Value of Image Fusion in Coronary Angiography for the Detection of Coronary Artery Bypass Grafts

BACKGROUND

Coronary angiography is more complex in patients with coronary artery bypass grafts (CABG). Image fusion is a new technology that allows the overlay of a computed tomography (CT) three-dimension (3D) model with fluoroscopic images in real time.

METHODS AND RESULTS

This single-center prospective study included 66 previous CABG patients undergoing coronary and bypass graft angiography. Image fusion coronary angiographies (fusion group, 20 patients) were compared to conventional coronary angiographies (control group, 46 patients). The fusion group included patients for whom a previous chest CT scan with contrast was available. For patients in this group, aorta and CABG were reconstructed in 3D from CT acquisitions and merged in real time with fluoroscopic images. The following parameters were compared: time needed to localize the CABG; procedure duration; air kerma (AK); dose area product (DAP); and volume of contrast media injected. Results are expressed as median. There were no significant differences between the 2 groups in patient demographics and procedure characteristics (access site, number of bypass to be found, and interventional cardiologist's experience). The time to localize CABG was significantly shorter in the fusion group (7.3 versus 12.4 minutes; P=0.002), as well as the procedure duration (20.6 versus 25.6 minutes; P=0.002), AK (610 versus 814 mGy; P=0.02), DAP (4390 versus 5922.5 cGy·cm(2); P=0.02), and volume of iodinated contrast media (85 versus 116 cc; P=0.002).

CONCLUSIONS

3D image fusion improves the CABG detection in coronary angiography and reduces the time necessary to localize CABG, total procedure time duration, radiation exposure, and volume of contrast media.

A simple method for proximal anastomoses marking during CABG for future coronary angiography

Evaluation of aortic proximal anastomoses in patients who have undergone coronary artery bypass surgery poses a special challenge to the interventional cardiologist during follow-up angiography procedures. We present a simple, safe, and fast technique for proximal anastomoses marking using hemostatic clips. Successful visualization of the graft marker was achieved using medium-sized hemoclips during fluoroscopy. The use of hemoclips for this procedure proved to be straightforward and required no additional surgical training.

Impact on contrast, fluoroscopy, and catheter utilization from knowing the coronary artery bypass graft anatomy before diagnostic coronary angiography

To what extent the unavailability of coronary artery bypass graft (CABG) anatomy complicates the performance of diagnostic coronary angiography has not been studied. The medical and catheterization records and coronary angiograms of 367 consecutive CABG surgery patients who underwent 394 diagnostic coronary angiographic studies from October 1, 2004, to May 31, 2007, were retrospectively reviewed. The patients' mean age was 65+/-9 years, and 97% were men. The mean interval from CABG surgery to angiography was 8.3+/-6.1 years. Patent left internal mammary artery grafts were found in 75%, and the mean number of patent grafts was 2.1+/-1.0. Compared with angiograms with known CABG anatomy, angiograms with unknown CABG anatomy (26%) required significantly higher amounts of contrast (189+/-7 vs 158+/-4 ml), longer fluoroscopy times (14.0+/-0.7 vs 10.6+/-0.4 minutes), and more diagnostic catheters (3.0+/-0.1 vs 2.5+/-0.05) (p<0.001 for all comparisons). The unavailability of CABG anatomy remained associated with increased contrast, fluoroscopy, and catheter use after multivariate adjustment. Proximal anastomotic bypass markers were associated with lower contrast use but were seen in only 9% of patients. In conclusion, the unavailability of CABG anatomy significantly and independently increases the use of contrast, fluoroscopy, and catheters during diagnostic coronary angiography. Every effort should be made to obtain CABG anatomy before diagnostic angiography is performed.

Impact of saphenous vein graft radiographic markers on clinical events and angiographic parameters

BACKGROUND

Use of saphenous vein graft (SVG) radiographic markers has been associated with shorter cardiac catheterization procedure times and reduced contrast agent volume for postoperative coronary artery bypass graft (CABG) catheterizations. Use of such markers is varied and often operator-dependent, as the effect of SVG markers has not been fully evaluated. The goal of the present analysis was to evaluate the association of SVG markers with clinical outcomes and graft patency.

METHODS

Data were drawn from the Project of Ex-vivo Vein Graft Engineering via Transfection (PREVENT) IV trial of patients undergoing CABG at 107 hospitals across the United States. Repeat angiography was performed within 12 to 18 months after CABG. The SVG markers were used at the discretion of the surgeon and were identified on the follow-up angiogram as any device used to mark the ostium, regardless of shape.

RESULTS

The SVG markers were present in 51.2% of evaluable patients (910 of 1,778) and 52.3% of SVGs (2,228 of 4,240). Among patients with totally occluded SVGs (n = 911), visual identification of the SVG was obtained more frequently in those with an SVG marker (90.7% vs 72.1%, p < 0.001). The SVG stenosis 70% or greater at follow-up did not differ by use of markers (25.8% with marker vs 24.4% without marker, p = not significant). These findings were also consistent in ostial lesions (n = 942). Long-term death or myocardial infarction (MI) was similar by use of marker. The perioperative CABG MI was higher in patients with SVG markers (10.1% vs 5.5%, odds ratio adjusted 1.86, p = 0.021).

CONCLUSIONS

Saphenous vein graft radiographic markers were associated with higher rates of direct visualization of totally occluded SVGs without an adverse effect on graft patency or long-term clinical outcomes, but the association of SVG markers with increased perioperative CABG MI warrants further examination.

Value of saphenous vein graft markers during subsequent diagnostic cardiac catheterization

BACKGROUND

Although saphenous vein graft (SVG) markers have been available for many years, they have not been widely used in coronary artery bypass graft (CABG) surgery. This is likely due to the paucity of data regarding the utility of these markers in postsurgery cardiac catheterization.

METHODS

We performed a prospective study of all post-CABG patients undergoing cardiac catheterization at Barnes-Jewish Hospital over a 6-month period to test our hypothesis that SVG markers would have a beneficial effect on these procedures. Differences in total procedure (arterial) time, time to image only the SVGs, fluoroscopy time, amount of contrast used, number of aortotomies, and number of views required were compared in patients with and without markers.

RESULTS

Post-CABG patients undergoing catheterization who had markers (n = 76) required significantly less total procedure time (p = 0.007), fluoroscopy time (p = 0.02), and contrast use (p = 0.008). Even after adjusting for the numbers of SVG ostia and numbers of cine views, patients with markers still required less catheterization and fluoroscopy time (p < 0.01, p < 0.02) and time to image only the SVGs (p < 0.05) than those without markers (n = 106).

CONCLUSIONS

SVG markers improve the efficiency of post-CABG catheterizations; they decrease the exposure of patients and cardiologists to ionizing radiation, and they decrease the exposure of patients to potentially toxic contrast agents. SVG markers are beneficial to the vast majority of post-CABG patients.

Prevalence of aortocoronary graft marker use and the factors affecting this decision

BACKGROUND

Despite quantifiable evidence that aortocoronary graft marker (ACGM) insertion is associated with a beneficial impact at postoperative angiography, the choice whether or not to insert them at the time of bypass surgery remains optional.

METHODS

A one-time anonymous membership survey of the Society of Thoracic Surgeons was used to determine the prevalence of ACGM use and obtain demographic data regarding (1) the type of ACGM inserted, (2) reasons influencing the decision as to whether or not to use ACGMs, and (3) the occurrence of possible related complications.

RESULTS

Thirty-nine percent (1,405 of 3,558) and 37% (198 of 531) were returned from within and outside the Unites States, respectively. Sixty percent of US respondents routinely insert ACGMs in the majority of their individual cases. The most frequent reason to not insert ACGMs was a "lack of perceived benefit."

CONCLUSIONS

The majority of respondents practicing within the United States routinely insert ACGMs at the time of surgery. As no complication directly attributable to the use of graft markers has been reported, further study is warranted to determine the actual complication rate, although it is expected to be low.

Impact of aorto-coronary graft markers on subsequent graft patency: a retrospective review

The use of aorto-coronary graft markers has not been standard, presumably due to concern about possible adverse effects on subsequent graft patency. Our goal was to determine if there was any increased risk of graft occlusion in patients who received circumferential graft markers at the time of their coronary artery bypass (CAB) surgery. A retrospective review of angiograms was performed for patients with prior CAB. Cohorts with and without graft markers were compared. A total of 405 "unmarked" and 311 "marked" grafts were identified in 335 patients meeting inclusion criteria. Patency is reported in divisions of elapsed time since CAB. Overall patency in the "marked" group (71.1%) was significantly higher than in the "unmarked" group (58.0%, P < 0.001). In this retrospective population, there was no increased risk of graft occlusion in patients who received circumferential graft markers at the time of CAB surgery as compared to those patients who did not.