First Clinical Experience With the HEARTSTRING, a Device for Proximal Anastomoses in Coronary Surgery

Outcomes of 881 Consecutive Coronary Artery Bypass Graft Patients Using Heartstring Device

BACKGROUNDS

 One of the strategies to prevent stroke after coronary artery bypass grafting (CABG) may be the use of a device for proximal anastomosis without partial clamp of the ascending aorta.

METHODS

 We retrospectively investigated early and late outcomes in consecutive 881 patients undergoing isolated CABG using Heartstring for proximal anastomosis from January 2008 to December 2022, to reveal the validity to use it. All patients underwent preoperative imaging workups to evaluate neurovascular atherosclerosis.

RESULTS

 The mean age of the patients was 68.9 years, 20% were female and 13% had previous history of stroke. CABG was on-pump beating heart (52.2%) or off-pump (47.8%) with a mean number of distal anastomoses of 3.38 ± 0.93, using 1.62 ± 0.53 Heartstring devices under different aortic manipulations. In-hospital mortality was 2.0% and perioperative stroke rate was 0.9%, none of them died during hospital stay. During the follow-up period of 70 ± 47 months, the overall actuarial survival rates were 86 and 66%, and major adverse cardiac and cerebrovascular events (MACCEs)-free rates were 86 and 70% at 5 and 10 years, respectively. On multivariable analysis, risk factors for late death included male, previous history of stroke, postoperative sternomediastinitis, late new-onset stroke, and MACCEs, but did not include the perioperative stroke.

CONCLUSION

 Low stroke rate, as low as 0.9%, after CABG using Heartstring for proximal anastomosis, although under a variety of aortic manipulations, may contribute to the improved long-term prognosis.

Incidence of postoperative stroke using the Heartstring device in 1,380 coronary artery bypass graft patients with mild to severe atherosclerosis of the ascending aorta

BACKGROUND

Atherosclerotic disease of the ascending aorta during coronary artery bypass graft surgery (CABG) increases the risk for postoperative stroke. The objective of this study was to examine the incidence of postoperative stroke in CABG utilizing the Heartstring (Maquet Cardiovascular, San Jose, CA) proximal anastomotic device.

METHODS

Intraoperative epiaortic ultrasonography was used to grade atherosclerosis in CABG patients at Emory University from April 2003 to December 2012. The Heartstring device was utilized in 1,380 patients: 407 (29.5%) grade I (minimal atherosclerosis), 367 (26.6%) grade II, 437 (31.7%) grade III, 110 (8.0%) grade IV, and 59 (4.3%) grade V (severe atherosclerosis). Logistic regression analysis was used to estimate the effect of aortic grade on outcomes adjusted for Society of Thoracic Surgeons predicted risk of mortality and predicted risk of stroke scores.

RESULTS

The mean age of all patients was 66.7 ± 10.5 years, and 31.9% were female. An increasing risk profile was apparent with rising aortic grade. Most CABG was done off pump (n = 1,277, 92.5%). There was no significant association between aortic grade and frequency of postoperative stroke (p = 0.83). In all patients, use of the Heartstring device reduced the predicted risk of stroke by 44% (O:E risk 0.56). The benefit for postoperative stroke was least apparent in the grade I aorta patients (O:E 0.8) compared with patients having grade II and greater. There were no strokes among patients with severe atherosclerosis using the Heartstring device.

CONCLUSIONS

Compared with the Society of Thoracic Surgeons predicted risk for stroke, the Heartstring proximal anastomotic device can be safely used with all aortic grades. The most prominent benefit appears to be for patients with grade II disease and greater.

Avoidance of aortic side-clamping for proximal bypass anastomoses: better short-term outcome?

OBJECTIVES

The benefit of off-pump coronary artery bypass (OPCAB) surgery may be reduced by strokes caused by microemboli produced after aortic side-clamping for proximal bypass anastomoses. The Heartstring device allows constructing proximal bypass anastomoses without side-clamping of the aorta.

METHODS

This retrospective study describes 260 consecutive patients who underwent OPCAB surgery; 442 proximal anastomoses were performed with the Heartstring device in this series. Ten percent of the patients were randomly sampled before discharge to undergo a coronary angiogram for assessment of graft patency.

RESULTS

Intraoperative Doppler measurements confirmed regular bypass function. Early mortality occurred in 4 patients (1.5%), and stroke occurred in 2 patients (0.8%). Device-related bleeding was negligible, and there were no cases of aortic dissection. Perioperative ischemia occurred in 8 patients (3.1%). Predischarge coronary angiography evaluations in 25 of the patients (of 260) showed that all 42 Heartstring-assisted anastomoses (of 442) were patent.

CONCLUSIONS

Clampless performance of proximal bypass anastomoses combined with OPCAB is associated with a very low incidence of stroke complications. Short-term follow-up has shown excellent results regarding bypass patency and other adverse events. Prospective randomized trials are required to confirm the advantage of this technique.

Minimizing the risk of perioperative stroke by clampless off-pump bypass surgery: a retrospective observational analysis

Objectives

Stroke is a devastating complication after coronary artery bypass grafting, occurring in 1.4% to 4.3% of patients. A major cause of stroke is cerebral embolization of aortic atheromatous debris or calcified plaques. This report analyzes the incidence of stroke in patients treated according to the clampless concept, i.e. avoiding side-clamping of the aorta, by means of off-pump coronary artery bypass surgery (OPCAB) in combination with the HEARTSTRING device.

Methods

During a period of 43 months (2005-2008), 412 consecutive patients were treated with the above-mentioned method by one single surgeon. A minimum of one proximal aortal anastomosis was performed in each patient. Altogether, 542 proximal anastomosis were applied, each created by means of the HEARTSTRING device.

Results

The mean age of patients was 67+9.7 years, the predicted mortality 5.2% (logistic EuroSCORE) and the observed mortality 1.9%. Histories of preoperative neurological disorders or cerebrovascular diseases were documented in 15% of patients. The overall incidence of postoperative stroke was 0.48% in contrast to 1.3% according to the stroke risk score.

Conclusions

In accordance to previously published data, our results show that avoiding aortic side-clamping during OPCAB reduces postoperative stroke rates. The HEARTSTRING device is a safe option for creating proximal aortic anastomosis.

“Beyond Beating Heart Surgery” Heartstring Device Protects against Perioperative Neurological Events

Objective

There is a growing body of evidence favoring off-pump coronary artery bypass surgery (OPCAB) over traditional coronary artery bypass surgery (CABG) with cardiopulmonary bypass as a method for reducing perioperative neurologic events. Aortic manipulation, whether with OPCAB or coronary artery bypass surgery with cardiopulmonary bypass, is strongly linked with adverse neurologic outcomes. Although the aortic “no-touch” technique has merit, most cardiac surgeons are reluctant to base entire myocardial revascularization exclusively on mammary pedicles. The purpose of this study was to analyze our experience with OPCAB combined with the use of a Heartstring proximal anastomotic device, as a strategy for reducing clinically evident cerebrovascular accidents.

Methods

Two hundred twenty-seven consecutive isolated OPCAB were performed without the use of a side-biting aortic clamp. In all these operations, a Heartstring device was used, permitting clampless hand-sutured proximal anastomoses. All patients were managed in this fashion regardless of the status of their ascending aorta. A mean of 3.4 bypasses were performed during each operation, with one or two mammary arteries harvested routinely. In 98% of patients, a single proximal anastomosis was performed; there was liberal use of sequential bypass grafts.

Results

Mean age was 69.3 years, with 17% octogenarians. Preexisting cerebrovascular disease was present in 22.4% of patients. There were no clinically evident perioperative neurologic events in any patients. There were no operative deaths.

Conclusions

This series suggests that OPCAB performed with a single, clampless, proximal aortic anastomosis, and with a Heartstring device may protect against perioperative strokes.

The Use of Enclose(®)II Anastomosis Assist Device for the Proximal Coronary Branch Anastomosis to Vascular Graft

We used the Enclose(®)II anastomosis assist device (Novare Surgical Systems, Inc., CA, USA), which was originally developed as an ancillary device for proximal anastomosis in off-pump coronary artery bypass grafting (OPCAB), to assist anastomosis for the vascular grafts without clamping those conduits in two cases. In these cases, it was difficult to clump vascular graft partially, because vascular graft was short. So we used Enclose(®)II anastomosis assist device for these cases. The advantage of this method is that the Enclose(®)II anastomosis assist device facilitates the anastomosis of arterial side branches to the artificial graft (1) by eliminating the use of partial clamp on the artificial conduits and (2) by providing a plane surface for easy handling for suture.

Cerebral Emboli Generation during Off-Pump Coronary Artery Bypass Grafting with a Clampless Device versus Partial Clamping of the Ascending Aorta

Objective

It is not known whether use of a clampless facilitating device during proximal graft anastamosis decreases intraoperative cerebral emboli in patients with mild atherosclerotic ascending aorta (AAA) having off-pump coronary artery bypass.

Methods

After intraoperative epiaortic ultrasound showed no more than mild (grade I–II) atherosclerotic ascending aorta, 20 patients were randomized to receive either partial clamping (PC, n = 10) or the HEARTSTRING clampless device (HS, n = 9) for proximal graft construction on the ascending aorta. Continuous transcranial Doppler monitoring, with capability to discern gaseous from solid particulates, was used intraoperatively to monitor high-intensity transient signals (HITS) in the middle cerebral arteries. Postoperative diffusion-weighted brain magnetic resonance imaging documented old and new ischemic brain lesions.

Results

There were no significant differences between the groups in the number of proximals (P = 0.14), distals (P = 0.4), or intraoperative cell saver transfusions (P = 0.69). The total number of HITS was not significantly different between the PC and HS groups (P = 0.2). However, the number of solid HITS was significantly lower in the HS than in the PC group (2.7 ± 2.6 versus 14.0 ± 8.1; P < 0.001). The number of gaseous emboli in the HS group was fourfold greater when a mister-blower rather than a suction device was used to clear blood away from the HS site. Postoperatively, there were no deaths, myocardial infarctions, or clinical strokes observed in either group. Diffusion-weighted cerebral magnetic resonance imaging revealed no statistical difference between groups for new infarct lesions.

Conclusions

Use of the HS device during off-pump coronary artery bypass was associated with significantly fewer intraoperative solid emboli in the middle cerebral artery than PC of the ascending aorta.

"Gumnut" device for off-pump proximal aortocoronary anastomosis

Use of side-biting clamps in patients with coronary artery disease and atheromatous disease of ascending aorta, undergoing coronary artery surgery can lead to major postoperative neurological events. We describe the use of a simple device to avoid use of side-biting clamp on aorta for proximal aortocoronary anastomosis.

Easy technique for mounting the Heartstring system into the sheath

The Heartstring system was developed to avoid the use of side-biting aortic clamps, but the sealing system sometimes tears. To solve this problem, a string is wound around the coiled seal and pulled gently.

New device for saphenous vein-to-aorta proximal anastomosis without side-clamping

Background

Side clamping to perform saphenous vein-to-aorta proximal anastomosis is a well known cause of cerebral embolization during coronary bypass surgery. Automatic and manual devices have been introduced to avoid aortic clamping and facilitate proximal anastomosis but the manual ones only allow the traditional hand-sewing running suture. Nevertheless, they are not easy to use and very expensive to buy.

Methods

We developed a simple object that helps to perform a manual proximal anastomosis without the need to clamp the side of the aorta. This device is a steel bar which blocks the aortic hole and simultaneously it provides a slit to receive the needle. Through the slit comes out a thin, sharp, straight, but also well directed and predictable jet of blood which could be easily controlled during the suture.

Results

The function of the object is quite different from other devices. Nothing is deployed in the aorta. The object is only placed on the aorta with the small appendage slipped into the hole. The main advantage of the device is that while manipulation of the aorta is avoided no foreign bodies are incorporated in the suture and – most importantly – the aortic intima is not touched at all. The main drawback of the device is the blood jet coming from the slit so that the blood pressure has to be lowered by vasodilators during the anastomosis. Moreover, the suture has to change direction and the needle has to enter the aortic wall first to slip out through the slit.

Conclusion

The object was named "Slit Device" and is not a routine instrument. It would be only an alternative to other anastomotic devices with the same surgical indications. In the case of ascending aortic disease and saphenous vein grafting, the Slit Device avoids aortic clamping thereby preventing atheroembolism and also avoiding the need for hypothermic circulatory arrest in patients with unclampable aorta.

Gaseous and solid cerebral microembolization during proximal aortic anastomoses in off-pump coronary surgery: the effect of an aortic side-biting clamp and two clampless devices

OBJECTIVES

Intraoperative cerebral microembolism is a cause of cerebral dysfunction after cardiac surgery, and particulate microemboli are the most damaging. Using a new-generation transcranial Doppler ultrasound, we compared the number and nature of microemboli in patients undergoing off-pump coronary artery bypass grafting during performance of proximal anastomoses with three techniques: an aortic side-biting clamp and two clampless devices (the Enclose II device [Novare Surgical Systems, Inc, Cupertino, Calif] and the Heartstring II device [Guidant Corporation, Santa Clara, Calif]) developed to obviate the need for an aortic side-biting clamp, thereby reducing the number of cerebral microemboli.

METHODS

Bilateral continuous monitoring of the middle cerebral arteries was performed with a multirange, multifrequency transcranial Doppler device that both automatically rejects artifacts online and discriminates between solid and gaseous microemboli. Recordings were continuously undertaken during performance of 66 proximal aortic anastomoses in 42 patients. Thirty-five anastomoses were performed with an aortic side-biting clamp, 20 with the Enclose device, and 11 the Hearstring device.

RESULTS

Most microemboli occurred during application/insertion and removal of each device from the ascending aorta. The median number (interquartile range) of total microemboli was 11 (6-32) during side clamping, 11 (6-15) with the Enclose device, 40 (31-48) with the Heartstring device (P < .01). The proportion of solid microemboli was significantly higher in the side-clamp group (23%) compared with 6% and 1% in the Enclose and Heartstring groups, respectively (P < .01).

CONCLUSIONS

Avoidance of aortic side clamping results in a significant reduction in the proportion of solid microemboli detected with transcranial Doppler. As solid microemboli are probably the most damaging, use of the Enclose and Heartstring devices may represent an important strategy for minimizing cerebral injury during proximal aortic anastomoses.

Initial clinical experience with the Heartstring

OBJECTIVE

The Heartstring is one of the devices that enable proximal anastomosis without clamping the aorta. We have applied the device not only to low-risk patients with normal aortas but also to high-risk patients with diseased aortas. The purpose of this study was to investigate the initial outcomes of using this device.

METHODS

The Heartstring was used on 87 patients between January and December 2004. The patients comprised 62 men and 25 women 48-86 years old (mean 68.4 +/- 8.4 years). The ascending aorta was evaluated by computed tomography (CT) scanning before surgery. If a patient's aorta was severely calcified, epiaortic echocardiography was performed. The aortas were ranked into four grades, and the preoperative patient's status were evaluated by the EuroSCORE. Angiography was performed on the third postoperative day.

RESULTS

CT scanning revealed that 74 patients had no calcification in the ascending aorta, 10 patients had scattered calcification, and 3 patients had plate-like calcification. The EuroSCORE was 6.86 +/- 1.03. We performed 93 proximal anastomoses and 149 distal anastomoses. The average distal anastomosis was 1.6 +/- 0.6 sites per graft. Of the distal anastomoses, 74.2% were to the circumflex artery territory. Postoperative coronary angiography revealed that all grafts were patent.

CONCLUSION

The Heartstring facilitates safe proximal anastomosis, even in high-risk patients. Their short-term outcome was good. The device assists in bypassing circumflex artery territory. Long-term follow-up is necessary.

Revival of the side-to-side approach for distal coronary anastomosis

Side-to-side anastomosis was employed by just ten proportional stitches while performing distal anastomosis during coronary artery surgery. This technique is simple and quick. Here this simple technique is described in detail and the postoperative status of grafted conduits is reported.

Results with the Heartstring anastomotic device in patients with diseased ascending aorta

BACKGROUND

Avoidance of manipulation of diseased ascending aorta has been shown to be associated with a reduced risk of postoperative stroke after off-pump coronary artery bypass surgery (OPCAB). The use of the Heartstring device (Guidant, Indianapolis, USA) to accomplish a proximal aortic anastomosis without aortic clamping has been suggested in such patients.

PATIENTS AND METHODS

From April 2004 to December 2005, proximal aortic anastomoses have been accomplished employing the Heartstring device in 19 patients with calcified ascending aorta who underwent OPCAB. The diagnosis of diseased ascending aorta was made intraoperatively by epiaortic ultrasound scanning.

RESULTS

Eighteen vein grafts and three radial artery grafts have been successfully anastomosed to the ascending aorta by employing the Heartstring device. Breaking of eight seals occurred during insertion. One patient (5.2%) had stroke two days after urgent OPCAB.

CONCLUSION

The use of the Heartstring anastomotic device should be considered in high-risk patients with diseased ascending aorta requiring a prompt myocardial revascularization, whenever there is a place to safely insert this device into the ascending aorta.

Successful Coronary Revascularization Using the PAS-Port System in a Patient With Takayasu’s Arteritis and Behcet’s Disease

Coronary artery disease is rare in patients with Takayasu's arteritis or Behcet's disease. We report the case of a patient with concomitant Takayasu's arteritis and Behcet's disease who had angina pectoris develop due to severe narrowing of the left main coronary artery. The patient underwent revascularization with saphenous vein grafts with the assistance of the PAS-Port Proximal Anastomosis System (Cardica, Inc, Redwood City, CA). In conclusion, the PAS-Port Proximal Anastomosis System seems to be a safe and effective method of facilitating revascularization, particularly when severe calcification of the ascending aorta precludes cross-clamping during off-pump coronary artery bypass grafting.

The HEARTSTRING Proximal Seal System is a Possible Source of Atheroembolism

It is necessary to use side clamps to construct proximal anastomoses in off-pump coronary artery bypass, and this can be related to neurologic complications. Recently a new device, the HEARTSTRING device, was developed. We present a 78-year-old man who underwent emergent bypass surgery using the HEARTSTRING device to avoid a side clamp. We found atherosclerotic debris from the punched hole and, unfortunately, a postoperative neurological complication resulted. We strongly suggest that it is most important that potential candidates for the HEARTSTRING device be carefully selected to reduce possible neurologic complications. We report that while this new device is useful, there is a potential pitfall in using it; that it is a possible source of atheroembolism.