Outcomes of left internal mammary artery with saphenous vein composite graft to bypass the left anterior descending artery: a propensity-matched study

Saphenous vein to the right coronary system from the right thoracic artery or the aorta. Long-term propensity-matched results of 2 groups

OBJECTIVES

Since 2000, we anastomosed the saphenous vein graft to the right coronary artery system using the stump of the right internal thoracic artery as inflow. The long-term results of patients where the right coronary artery was grafted with the right internal thoracic artery or the ascending aorta as saphenous vein inflow has not been reported.

METHODS

From 2000 to 2018, 699 consecutive patients had right internal thoracic artery elongated with saphenous vein (I-graft group, n = 358, 51.2%) or saphenous vein from the aorta (Ao-graft group, n = 341, 48.8%) on right coronary artery system. Inclusion criteria were age ≤75 years, bilateral internal thoracic arteries as a Y graft on the left system (three-vessel disease, n = 603, 86.3%) or as a left internal thoracic artery on left anterior descending and right internal thoracic artery elongated with saphenous vein on the right coronary artery system (two-vessel disease, n = 96, 13.7%), only 1 saphenous vein per patient. Propensity-matching identified 272 patients per group. One-hundred and twenty-two patients underwent coronary computed tomographic angiography to asses grafts patency after a median follow-up of 88 (65-93) months.

RESULTS

In the paired samples, there was no difference in the early outcome. Ten-year survival and freedom from death, non-fatal acute myocardial infarction and repeat revascularization were higher in I-graft group: 90.6 [standard error (SE): 2.0] vs 78.2 (SE: 5.3), P = 0.0266, and 85.2 (SE: 2.4) vs 69.9 (SE: 5.3), P = 0.0179. Saphenous vein graft, at a long-time follow-up, showed a higher patency rate (81.6% (SE: 7.0) vs 50.7% (SE: 7.9), P < 0.0001) and a smaller internal lumen diameter (2.7, standard deviation: 0.4 vs 3.4, standard deviation: 0.6 mm, P < 0.0001) when right internal thoracic artery was the inflow.

CONCLUSIONS

Grafting the right coronary artery with saphenous vein may entail higher patency rate and better outcome when the inflow is the right internal thoracic artery than when is the ascending aorta. Prospective randomized data are needed to test this hypothesis.

Four case reports of left anterior descending restenosis treated via the internal mammary artery: A literature review

Objective

To analyse four cases of intervention via the internal mammary artery-anterior descending branch and provide and summarise the clinical treatment experience.

Methods

The clinical data of four patients with distal restenosis of a left anterior descending artery (LAD) anastomosis after left internal mammary artery (LIMA)-LAD bypass surgery, who were admitted to the Gansu Institute of Cardiovascular Diseases between March 2013 and April 2022, were retrospectively analysed and reviewed together with the relevant literature.

Results

Among the four patients, one was treated with intracoronary stenting via the internal mammary artery route, two were treated with intracoronary drug-coated balloon dilation (one of whom underwent fractional flow reserve [FFR] testing), and two underwent FFR testing (one of whom had a negative test result until the end of the procedure and continued to take medication during follow-up; the other patient had a positive result and further interventions). There were no deaths or postoperative complications in the group, and the patients were followed up for 4 months to 9 years, with good long-term outcomes.

Conclusion

Percutaneous coronary intervention (PCI) via the internal mammary artery route is safe and effective, and patients with anastomotic distal stenosis or anastomotic stenosis of LAD bypass anastomosis may be considered for PCI via the internal mammary artery route.

Anterolateral territory coronary artery bypass grafting strategies: a non-inferiority randomized clinical trial: the AMI-PONT trial

OBJECTIVES

The main objective was to assess whether a composite coronary artery bypass grafting strategy including a saphenous vein graft bridge to distribute left internal mammary artery outflow provides non-inferior patency rates compared to conventional grafting surgery with separated left internal mammary artery to left anterior descending coronary graft and aorto-coronary saphenous vein grafts to other anterolateral targets.

METHODS

All patients underwent isolated grafting surgery with cardiopulmonary bypass and received ≥2 grafts/patients on the anterolateral territory. The graft patency (i.e. non-occluded) was assessed using multislice spiral computed tomography at 1 year.

RESULTS

From 2012 to 2021, 208 patients were randomized to a bridge (n = 105) or conventional grafting strategy (n = 103). Patient characteristics were comparable between groups. The anterolateral graft patency was non-inferior in the composite bridge compared to conventional grafting strategy at 1 year [risk difference 0.7% (90% confidence interval -4.8 to 6.2%)]. The graft patency to the left anterior descending coronary was no different between groups (P = 0.175). Intraoperatively, the bridge group required shorter vein length for anterolateral targets (P < 0.001) and exhibited greater Doppler flow in the mammary artery pedicle (P = 0.004). The composite outcome of death, myocardial infarction or target vessel reintervention at 30 days was no different (P = 0.164).

CONCLUSIONS

Anterolateral graft patency of the composite bridge grafting strategy is non-inferior to the conventional grafting strategy at 1 year. This novel grafting strategy is safe, efficient, associated with several advantages including better mammary artery flow and shorter vein requirement, and could be a valuable alternative to conventional grafting strategies. Ten-year clinical follow-up is underway.

TRIAL REGISTRATION

ClinicalTrials.gov: NCT01585285.

Left Internal Mammary Artery as an Endocrine Organ: Insights Into Graft Biology and Long-term Impact Following Coronary Artery Bypass Grafting

The left internal mammary artery (LIMA) is considered the criterion standard vessel for use in coronary artery bypass grafting. In recent decades, countless studies have documented its superiority over other arterial and venous coronary artery bypass grafting conduits, although the full mechanisms for this superiority remain unknown. A growing body of literature has unveiled the importance of extracellular vesicles known as exosomes in cardiovascular signaling and various pathologic states. In this review, we briefly compare the clinical longevity of the LIMA relative to other conduits, explore the effects of varying grafting techniques on clinical and angiographic outcomes, and provide physiologic insights into graft function on a cellular and molecular level. Finally, we explore exosome signaling as it pertains to atherosclerosis in support of the LIMA as an "endocrine organ."

One-Stop Hybrid Coronary Revascularization Versus Off-Pump Coronary Artery Bypass Grafting in Patients With Multivessel Coronary Artery Disease

Background: Data on one-stop hybrid coronary revascularization (HCR) are limited. This study aimed to compare the early and midterm outcomes of one-stop HCR with off-pump coronary artery bypass grafting (OPCAB) in patients with multivessel coronary artery disease.

Methods: From April 2018 to May 2021, 752 patients with multivessel coronary artery disease who underwent isolated one-stop HCR or OPCAB were retrospectively included in this analysis. After exclusion and propensity score matching, 151 patients who underwent HCR were matched with 151 patients who underwent OPCAB. The primary endpoints were midterm major adverse cardiovascular and cerebrovascular events (MACCE) after the procedure. The secondary endpoints were in-hospital complications and outcomes.

Results: The preprocedural characteristics were well balanced between the two groups after matching. The HCR group was associated with a lower rate of perioperative transfusion (23.8 vs. 53.0%, p < 0.001) and new-onset atrial fibrillation (AF) (5.3 vs. 15.2%, p = 0.004), shorter time of mechanical ventilation (h) [15 (16, 17) vs. 17 (16, 20), p < 0.001], and shorter length of stay (LOS) in the hospital (days) [19 (16, 24) vs. 22 (18, 27), p = 0.001]. Cumulated MACCE rates were similar between the two groups (15.9 vs. 14.0%, p = 0.59) during a median follow-up of 20 months.

Conclusions: One-stop HCR is safe and efficacious with less invasiveness and faster postoperative recovery in selected patients with multivessel coronary artery disease. Randomized controlled trials with larger sample sizes and long-term follow-up are warranted to confirm these findings.