Prospective Evaluation of Patency and Early Experience Utilizing an Automated Distal Anastomosis Device (C-Port)

Sutureless versus Hand-Sewn Coronary Anastomoses: A Systematic Review and Meta-Analysis

BACKGROUND

Sutureless coronary anastomotic devices are intended to facilitate minimally invasive coronary artery bypass grafting (MICS-CABG) by easing and eventually standardizing the anastomotic technique. Within this systematic review and meta-analysis, we aim to determine patency and to evaluate safety outcomes for the sutureless anastomoses.

METHODS

CENTRAL, MEDLINE, and EMBASE were searched from database start till August 2021 in a predefined search strategy combining the key concepts: 'coronary artery bypass grafting', 'sutureless coronary anastomoses', and 'hand-sewn coronary anastomoses' by the Boolean operation 'AND'. Study characteristics, patient demographics, interventional details, and all available outcome data were extracted. A meta-analysis was performed on patency at longest follow-up. Safety outcomes were presented.

RESULTS

A total of eleven trials towards six sutureless anastomotic devices were included, comprising 3724 patients (490 sutureless and 3234 hand-sewn). There was no significant difference in patency at a mean follow-up duration of 546.3 (range 1.5-2691) days, with a risk ratio of 0.77 (95% CI 0.55-1.06). MACE was reported in 4.5% sutureless and 3.9% hand-sewn patients, including all-cause mortality (resp. 1.3 vs. 1.9%), myocardial infarction (resp. 1.6 vs. 1.7%), and coronary revascularization (resp. 1.8 vs. 0.5%). Incomplete hemostasis occurred in 24.8% of the sutureless anastomoses. Intra-operative device failure forced conversion to hand-sewn or redo-anastomosis in 5.8% of the sutureless cases.

CONCLUSION

Based on the systematic review and meta-analysis including six devices, we conclude that sutureless coronary anastomotic devices appear safe and effective when used by well-trained and dedicated surgical teams.

Robotic Total Endoscopic Coronary Bypass in 570 Patients: Impact of Anastomotic Technique in 2 Eras

BACKGROUND

In coronary bypass grafting, including robotic off-pump totally-endoscopic coronary bypass (TECAB), the anastomotic technique is the most critical part of the procedure. We reviewed results in 570 patients over a 7-year period and compared outcomes between to eras, based on predominant anastomotic technique: connectors versus running suture.

METHODS

Between 7/2013-12/2020, 570 patients underwent off-pump TECAB. Group-1 (378 patients, 7/2013-8/2018) using predominantly the C-Port Flex A^TM distal anastomotic stapler (Aesculap, Tuttlingen Germany), Group-2 (192 patients, 9/2018-12/2020) using predominantly a sutured technique (7-0 Pronova^TM, Johnson and Johnson, USA). Retrospective analysis of clinical outcomes was performed.

RESULTS

Off-pump TECAB was completed in 98.8% (563/570 patients) with an Observed/Expected mortality of 0.6 (6/570 patients). The anastomotic device was used in 89% of 626 grafts in Group-1 and only 11% of 305 grafts in Group-2 (p=0.001). There were no differences in multivessel TECAB (57%vs.53%;p=0.331) or bilateral internal thoracic artery use (50%vs.43%;p=0.127) in Group-1 vs Group-2, respectively. Operative time was shorter in Group-1 (242+84 min vs. 273+88 min;p<0.001). Early clinical outcomes were similar between groups, except for hospital stay which was longer in Group-1 (2.9vs2.3 days;p<0.001). Graft patency was similar (98%vs95%;p=0.295) in Group-1 vs Group-2, respectively.

CONCLUSIONS

Changing the predominant approach from stapled anastomosis to a sutured technique during robotic TECAB resulted in longer operative times. Both approaches led to excellent outcomes, including graft patency. The shorter operative times conferred by using staplers may flatten the learning curve and facilitate broader adoption of TECAB.

Preclinical Feasibility and Patency Analyses of a New Distal Coronary Connector: The ELANA Heart Bypass

Objective

This preclinical study determines the feasibility and 6-month patency rates of a new distal coronary connector, the Excimer Laser Assisted Nonocclusive Anastomosis (ELANA) Heart Bypass.

Methods

Twenty Dutch Landrace pigs received either a hand-sewn (n = 8) or an ELANA (n = 12) left internal thoracic artery to left anterior descending artery anastomosis, using off-pump coronary artery bypass grafting. Six-month patency rates were demonstrated by coronary angiography and histological evaluation. Throughout, procedural details and complication rates were collected.

Results

The ELANA Heart Bypass demonstrated 0% mortality and complication rates during follow-up. It was demonstrated feasible, with comparable perioperative flow measurements (ELANA vs hand-sewn, median [min to max], 24 [14 to 28] vs 17 [12 to 31] mL/min; P = 0.601) and fast construction times (3 [3 to 7] vs 31 [26 to 37] min; P < 0.001). Yet, an extra hemostatic stitch was needed in 25% of the ELANA versus 12.5% of the hand-sewn anastomoses. The 6-month patency rate of the ELANA Heart Bypass was 83.3% versus 100% in hand-sewn anastomoses. The 2 occluded ELANA-anastomoses were defined model-based errors.

Conclusions

The ELANA Heart Bypass facilitates a sutureless distal coronary anastomosis. A design change is suggested to improve hemostasis and will be evaluated in future translational studies. This new technique is a potential alternative to hand-sewn anastomoses in (minimally invasive) coronary surgery.

Angiographic patency after robotic beating heart totally endoscopic coronary artery bypass grafting facilitated by automated distal anastomotic connectors

OBJECTIVES

Robotic totally endoscopic coronary artery bypass (TECAB) on the beating heart has been facilitated in our experience using distal coronary anastomotic connectors. In this study, we retrospectively reviewed graft patency in all robotic TECAB patients who underwent formal angiography at our current institution over a 5-year period.

METHODS

Between July 2013 and June 2018, 361 consecutive patients underwent robotic beating-heart TECAB. Of these patients, 121 had a follow-up angiogram, which assessed graft patency. Eighty-four patients had an angiogram as part of planned hybrid procedures and 37 patients underwent an unplanned angiogram for clinical indications. Retrospective analysis of angiographic patency and clinical outcomes was performed.

RESULTS

The mean Society of Thoracic Surgeons predicted risk of mortality was 1.8%. Single-vessel bypass was performed in 40 (33%) patients and multivessel grafting in 81 (67%). Average flow (ml/min) and pulsatility index in the grafts was 74.7 ± 39.1 and 1.42 ± 0.52, respectively. The number of grafts evaluated was 204 (130 left internal mammary artery and 74 right internal mammary artery grafts). The median time to angiography was 1.0 and 16.0 months and graft patency was 98% and 91% in the hybrid and non-hybrid groups, respectively. Overall graft patency was 95.6% (left internal mammary artery = 96%; right internal mammary artery = 93%). Left internal mammary artery to left anterior descending artery graft patency was 97%. Clinical follow-up was available for 316 (88%) patients at mean 22.5 ± 15.1 months. Freedom from major adverse cardiac events at 2 years was 92%.

CONCLUSIONS

In this consecutive series of patients undergoing formal angiography after robotic single and multivessel TECAB, we found satisfactory graft patency and 2-year clinical outcomes. Longer-term follow-up is warranted.

Multicenter Assessment of Grafts in Coronaries: Midterm Evaluation of the C-Port Device (the MAGIC Study)

OBJECTIVE

The commercially available C-Port distal anastomotic device (Food and Drug Administration cleared in 2007) is an automated miniature vascular stapler that performs the coronary anastomosis. This prospective multicenter registry sought to evaluate midterm patency using this device compared with hand-sewn grafts.

METHODS

Patients receiving at least one C-Port anastomosis during coronary artery bypass grafting surgery were enrolled at eight sites. Of the 117 patients enrolled, 78 patients (67%) with 104 C-Port vein grafts completed the study to patency assessment via computed tomography angiography. Clinical follow-up and index graft patency (Gated 64-slice computed tomography scan) were performed at least 12 months postoperatively. The primary efficacy endpoint was patency compared with the peer-reviewed results from the PRoject of Ex-vivo Vein graft ENgineering via Transfection IV (PREVENT IV) trial.

RESULTS

The patient population was consistent with the PREVENT IV placebo cohort. The mortality at 12 months was 0.85% (1/117). The major cardiac morbidity rate was 3.4% (4/117). The C-Port vein graft occlusion rate was 16.3% (17/104) compared with 26.6% (597/2242) in the PREVENT IV trial (P = 0.011). Within this study, C-Port graft occlusion rates were not significantly different from the hand-sewn grafts (P = 0.821).

CONCLUSIONS

The C-Port device is safe and effective in creating the distal anastomosis with equivalent patency rates to hand-sewn grafts at 12 months. When compared with hand-sewn anastomoses from a recent large prospective trial, the C-Port device demonstrated a statistically significant reduction in midterm graft occlusion. Further studies are required to evaluate its effect in less invasive coronary surgery.

A systematic review of the safety and efficacy of distal coronary artery anastomotic devices

Interest in minimally invasive and off-pump cardiac surgical techniques has promoted the development of automated distal anastomotic devices (DADs) to facilitate construction of coronary artery anastomosis. Several DADs have been proposed for potential use in coronary surgery. However, a number of technical failures and uncertainty around both short-term morbidity and long-term patency have limited the generalized uptake of these devices. A systematic literature search identified 28 studies, incorporating 970 patients who underwent coronary artery bypass grafting using a DAD. Eight different devices were identified including Heartflo, St Jude, U-clip, vessel closure system, C-port, magnetic vascular positioner and coronary anastomosis coupler. Thirty-day mortality, cardiac-specific mortality and myocardial infarction were equal between DADs and hand-sewn cases (1.3, 0.3 and 0.8%, respectively). The overall proportion of postoperative haemorrhage was higher in the anastomotic device group (2.3%) than in the group with hand-sewn anastomoses (1.5%) although not statistically significant. Overall graft patency was 97.2% at <1 month, 94.6% at 1-3 months and 92.3% at >3 months. Of the currently available systems, the U-clip device was found to provide the best overall postoperative outcomes, which included a patency of 96.1% at >3months. The current literature is limited by its predominantly observational study design and lack of directly comparative studies. Furthermore, inter-study variation in patient selection, anticoagulation strategies and follow-up periods prevents quantitative comparison. Future research necessitates multicentre randomized, controlled studies to provide a direct comparison of current and future anastomotic device systems with established hand-sewn techniques in both the short and long term.

Distal anastomotic patency of the Cardica C-PORT(R) xA system versus the hand-sewn technique: a prospective randomized controlled study in patients undergoing coronary artery bypass grafting

OBJECTIVES

The C-Port® Distal Anastomosis Systems (Cardica, Inc., Redwood City, CA, USA) demonstrated favourable results in feasibility trials. However, distal vein anastomoses created with the C-Port® or C-Port xA® system have never been compared with hand-sewn distal vein anastomoses. The objective of this study was to compare distal end-to-side anastomoses facilitated with the C-Port xA® System with the traditional hand-sewn method.

METHODS

This single-centre prospective randomized controlled study comprised 71 patients (device group n = 35, control group n = 36) who underwent primary elective coronary artery bypass grafting between June 2008 and April 2011. The primary study end-point was 12-month distal anastomotic patency, which was assessed with prospective ECG-gated 256-multislice computed tomographic coronary angiography using a step-and-shoot scanning protocol. For the primary end-point, a per-protocol analysis was used.

RESULTS

In the device group, four (11%) anastomoses were converted to hand-sewn anastomoses, and additional stitches to achieve haemostasis were necessary in 22 (76%) patients. There was no hospital mortality in either group. During the 12-month follow-up, a single death occurred in the Device group and was unrelated to the device. Twenty-nine patients in the device group and 32 in the control group completed 12-month CT coronary angiography. The overall patency of 160 studied distal vein graft anastomoses was 93%. Comparison of the end-to-side target anastomosis showed 12-month patencies of 86 and 88% in the device group and the control group, respectively.

CONCLUSIONS

According to these preliminary results and despite the limited number of patients, the use of the C-Port xA® System is safe enough to perform distal end-to-side vein graft anastomosis, with respect to 12-month end-to-side distal venous anastomotic patency. Although there are some technical challenges with this device, the incidence of complications is comparable to the traditional hand-sewn technique.

Early Patency Evaluation of New Distal Anastomotic Device in Internal Mammary Artery Grafts Using Computed Tomography Angiography

Introduction

Traditional coronary artery bypass grafting is performed using a hand sewn technique. The C-Port xA and Flex A anastomotic stapling devices (Cardica Inc., Redwood City, CA) were cleared by the Food and Drug Administration for use in distal coronary anastomoses in November 2006 and April 2007, respectively. They provide the ability to create a compliant, consistently reproducible, and automated anastomosis. Multidetector computed tomography (CT) has been shown to be effective in evaluating coronary artery bypass graft patency.

Methods

The first 24 patients to undergo internal mammary artery (IMA) anastomosis using the automated device in our practice were included in the study. Twenty-five IMA grafts (24 left IMA and 1 right IMA) were created using the C-Port xA or Flex A anastomotic device as part of multivessel off-pump coronary revascularization by sternotomy. Graft patency was evaluated at 30 days in the first 10 grafts and at 90 days in the next 15 grafts using multidetector (64 slice) CT.

Results

There were no device failures. There were no perioperative strokes, myocardial infarctions, or deaths. All 10 IMA grafts evaluated at 30 days were patent using multidetector CT. One of the 15 IMA grafts studied at 90 days was occluded using multidetector computed tomography.

Conclusions

The C-Port xA and Flex A distal anastomotic devices provided a safe and effective means to create a left IMA-left anterior descending artery anastomoses in coronary bypass surgery with excellent short to midterm patency in this early experience. Long-term follow-up is warranted. These findings will have important implications for future sternal sparing coronary bypass surgery.

The Current Status of Anastomotic Devices for Coronary Artery Bypass Surgery

The purpose of this article is to briefly review the history of proximal and distal anastomotic devices and to discuss presently available devices. Clinical outcome data from the EPIC Trial of the Cardica PAS-Port Proximal Anastomosis System will also be presented.