Anaortic, total-arterial, off-pump coronary artery bypass surgery: why bother?

Sex-differences in outcome after off-pump coronary artery bypass grafting is age-dependent; data from the Netherlands Heart Registration

Background

Women are known to have worse outcome after coronary artery bypass grafting (CABG) than men. Studies have shown that off-pump coronary artery bypass grafting (OPCAB) might benefit higher-risk patients, and therefore might also benefit women. We aimed to determine differences in early and late outcomes between sexes after OPCAB.

Methods

Data from all patients undergoing OPCAB, between 2013 through 2021 was retrieved from the Netherlands Heart Registration (NHR) database. Primary outcomes were early mortality, morbidity and late survival. We divided the population into subgroups based on age (aged ≥70 years or < 70 years) and sex.

Results

This study included 8,487 men and 2,170 women (total = 10,657). Female patients received fewer anastomoses (mean (SD)) women 2.38 (1.17) vs men 2.68 (1.23), p < 0.001) and total arterial revascularization was performed less frequently in women than in men (21.3 % versus 29.5 % respectively, p < 0.001).In the subgroup of patients <70 years, early mortality was 1.7 % in women and 0.6 % in men (p < 0.001). Survival rate at 5 years was 88.4 % in women and 91.1 % in men (p < 0.001). Female sex was associated with worse late survival in the subgroup <70 years (HR (95 % CI) 1.42 (1.10-1.83) p = 0.008).

Conclusions

Sex-differences in outcome after CABG persists in OPCAB surgery. However, these differences are solely present in the younger subgroup. In our data, women undergoing OPCAB surgery seem to be treated differently during surgery as compared to their male counter parts, further research is needed to analyze this finding.

Total arterial off-pump coronary revascularization: The Holy Grail?

PURPOSE OF REVIEW

Coronary artery bypass grafting (CABG) remains the standard of care for patients with complex multivessel coronary artery disease. However, conventional CABG utilizing left internal mammary artery and supplemental vein grafts performed on cardiopulmonary bypass is marred by questionable long-term patency of vein grafts and risk of neurological injury. Total arterial off-pump CABG is a strategy associated with avoidance of neurological injury and vein graft failure. The aim of this review is to summarize recent evidence on safety and effectiveness of total arterial off-pump CABG.

RECENT FINDINGS

Two key studies have been published recently. One describes a dual inflow technique that achieves anaortic, off-pump complete revascularization using arterial grafts only. The other is single centre study that reports 10-year survival of 89.33%, rate of freedom from repeat revascularization of 91.33% and early stroke rate of 0.9% after total arterial off-pump CABG.

SUMMARY

Total arterial off-pump CABG with its advantages of improved survival, enhanced freedom from repeat revascularization and low stroke rate can be regarded as the Holy Grail of myocardial revascularization. However, the results of a large, multicenter, prospective trial are required to substantiate this status.

Total arterial coronary revascularization

Arterial coronary grafts can be used in the majority of patients and have better patencies than saphenous vein grafts (SVGs), resulting in excellent perioperative and superior long-term outcomes. Barriers to their extensive use include potential for trauma and spasm, extra-operating time, unfamiliarity, concerns over hypoperfusion and deep sternal wound infection in patients in whom bilateral internal thoracic arteries are used-especially diabetics. This presentation addresses these concerns with particular attention to the radial artery, and skeletonized right internal thoracic artery harvest and construction of the proximal anastomoses of these grafts to the ascending thoracic aorta. The facile handling of these grafts and techniques identical to SVG grafting are emphasized. Avoidance of competitive flow and the importance of spasm prophylaxis cannot be overstated. Arterial grafts have patencies >90% at 10 years (SVG 50-60% at 10 years) and once functioning normally, remain free of atheroma. Long-term results are excellent, especially freedom from recurrent cardiac events and reoperations, even in patients with significant preoperative comorbidities such as diabetes and renal dysfunction. Depending on age, long-term survival is between 85 and 90% at 10 years and 75 and 80% at 15 years, and is always better than for one arterial graft plus SVG in all long-term risk-adjusted or propensity-matched studies.

HEARTSTRING enabled no-touch proximal anastomosis for off-pump coronary artery bypass grafting: current evidence and technique

Surgical revascularization remains the standard of care for many patients. Off-pump coronary artery bypass grafting (OPCAB) without cardiopulmonary bypass (CPB) has evolved during the past 20 years, and as such can significantly reduce the occurrence of neurological complications. While avoiding the aortic cross-clamping required in conventional on-pump techniques, OPCAB results in a lower incidence of stroke. However, clamp-related risk of stroke remains if partial or side-biting clamps are applied for proximal anastomoses. Others and we have demonstrated that no-touch 'anaortic' approaches avoiding any clamping during off-pump procedures via complete in situ grafting result in significantly reduced stroke rates when compared with partial clamping. Therefore, OPCAB in situ grafting has been proposed as the 'standard of care' to reduce neurological complications. However, this technique may not be applicable to for every patient as the use of free grafts (arterial or venous) requiring proximal anastomosis is often still necessary to achieve complete revascularization. In these situations, proximal anastomosis can be performed without a partial clamp by using the HEARTSTRING device, and over the last few years, considerable evidence has arisen supporting the impact of HEARTSTRING-enabled anastomosis to significantly minimize atheroembolism and neurological complications when compared with partial- or side-bite clamping. This paper provides a systematic overview and technical information about the combination of OPCAB and clampless strategies using the HEARTSTRING for proximal anastomosis to reduce stroke to levels reported for percutaneous coronary intervention.

Total arterial coronary revascularization-patient selection, stenoses, conduits, targets

Graft patency determines prognosis in coronary artery bypass grafting (CABG). Numerous reports over the past 20 years have documented superior patencies and prognosis when multiple arterial grafts are used, yet less than 10% of CABG have multiple arterial grafts. Several conduits have been proposed, with varying degrees of success. Saphenous vein grafts (SVG) begin to fail with intimal hypertrophy and then atheroma after 5 years, with patency rates of 50% to 60% at 10 years, and <30% at 15 years. In contrast, left internal thoracic artery (LITA) patency is >95% at 10 years and >90% at 20 years. The radial artery is extremely versatile and can reach all territories, but is muscular and vulnerable to spasm and competitive flow. Similarly, the right gastroepiploic artery is also muscular, and is best suited to the posterior descending coronary artery, especially in reoperations and is also affected by competitive flow. In addition, bilateral internal thoracic artery grafting (BITA) grafts and total arterial revascularization (TACR) can be performed with identical perioperative mortality (1%) and perioperative morbidity to LITA + SVG. Importantly, survival is superior-85% to 90% at 10 years versus 75% to 80% respectively. BITA/TACR patients also suffer fewer late cardiac events and reoperations, with superior results for older patients, those requiring urgent surgery, diabetics, patients with renal dysfunction and in reoperations. Contraindications to BITA include obesity, insulin dependent diabetics, and severe chronic obstructive airways disease. As such, arterial grafts have better patencies and clinical results. BITA/TACR is often underutilized, but can be achieved in the majority of patients. Opportunities exist to enhance BITA/TACR use in CABG to the potential benefit of our patients.

The history of arterial revascularization: from Kolesov to Tector and beyond

Coronary artery bypass grafting (CABG) is the one of the most effective revascularization strategies for patients with obstructive coronary artery disease. Total arterial revascularization using one or both internal thoracic and radial arteries has been shown to improve early outcomes and reduce long-term cardiovascular morbidity. Although CABG has evolved from an experimental procedure in the early 1900's to become one of the most commonly performed surgical procedures, there is still significant variation in grafting strategies amongst surgeons. We review the history and development of CABG with a particular emphasis on the early pioneers and the evolution of arterial grafting.