Since the advent of coronary artery bypass grafting (CABG), the selection of bypass conduits has always been one of the most controversial topics in this field. Arterial conduits have received extensive attention due to their excellent biological features and high patency. In recent years, the application of arterial grafting and total arterial grafting in China keeps increasing in recent years, but there is still a gap compared to the Europe and America. Previous clinical studies have indicated the benefits of the total arterial grafting in terms of patency and long-term outcomes, but the advantage of multiple arterial grafting over other procedures is still in need to be confirmed with high-quality randomized controlled trials. This article reviews the clinical application and strategy of total-arterial CABG, aiming to provide objective reference for future clinical research and application.
ObjectiveTo explore the effect of skeletonized left internal mammary artery (LIMA) in coronary artery bypass grafting (CABG). MethodsA total of 122 patients who underwent pure CABG were recruited in the study in the First Affiliated Hospital of China Medical University between January and April 2013. There were 77 males and 45 females with age of 41-76(62.8±10.5) years. They were randomly assigned to received CABG with skeletonized LIMAs (group A, 60 patients) or pedicle LIMAs (the group B, 62 patients) by random digital table. LIMAs were all anastomosised to the left anterior descending artery. ResultsThere was one patient failure in harvesting LIMA process in the group A and B respectively, and they were changed to saphenous vein grafts and excluded from the criteria. There were 2 and 3 patients of postoperative myocardial infarction in the group A and in the group B respectively, with incidence rate of 3.4% and 4.9% respectively (P > 0.05). One patient died in each group during hospitalization with hospital mortality rates of 1.7% and 1.6% respectively (P > 0.05). Complications such as mediastinal infection occurred zero and one patient in the group A and in the group B respectively (P > 0.05). LIMA harvesting time of the group A was statistically longer than that of the group B (30.7±7.2 min vs. 17.2±5.6 min, P < 0.05). In six months of follow-up after surgery, coronary CT showed patency rate of LIMA in the group A and in the group B was 96.8% and 100.0% respectively (P > 0.05). ConclusionThe recent effect of skeletonized LIMA as graft material in CABG is satisfactory.
ObjectiveTo explore the independent risk factors for early failure of internal mammary artery grafts after coronary artery bypass grafting (CABG), and to construct and preliminarily evaluate a risk prediction model for the decline of internal mammary artery bridges, optimizing postoperative risk stratification and management strategies for patients. MethodsA retrospective analysis was conducted on patients who underwent CABG at Fuwai Hospital, Chinese Academy of Medical Sciences from January 2016 to January 2020. The primary endpoint was the failure of the internal mammary artery bridge one year after surgery, and the secondary endpoint was major adverse cardiac and cerebrovascular events (MACCE) within five years after surgery, including all-cause death, myocardial infarction, stroke, and revascularization. Patients were divided into a failure group and a non-failure group based on whether there was early failure of the internal mammary artery bridge after surgery. Independent risk factors for the failure of the internal mammary artery bridge were explored through the least absolute shrinkage and selection operator regression and multivariate logistic regression, and a failure risk prediction model was constructed and cross-validated. Patients were stratified for MACCE risk according to the total score of independent risk factors, and the 5-year cumulative MACCE-free rate was drawn using the Kaplan-Meier method. ResultsA total of 657 patients were included, among whom there were 54 patients in the failure group, including 38 males and 16 females, with an average age of (61.85±8.03) years; there were 603 patients in the non-failure group, including 467 males and 136 females, with an average age of (60.45±8.23) years. Multivariate logistic regression analysis showed that non-left main lesion [OR=3.28, 95%CI (1.41, 7.62), P=0.006], pulsatility index (PI)>3.0 [OR=2.63, 95%CI (1.20, 5.75), P=0.016], quantitative flow ratio (QFR)>0.80 [OR=5.57, 95%CI (2.98, 10.41), P<0.001] and in-hospital complications [OR=4.02, 95%CI (1.59, 10.19), P=0.003] were independent risk factors for the failure of internal mammary artery grafts after CABG. Compared with the prediction model in previous literature [area under receiver operating characteristic curve was 0.632, 95%CI (0.561, 0.694)], the risk prediction model constructed with QFR>0.80, PI>3.0, non-left main lesion and in-hospital complications had a higher predictive ability for early failure of internal mammary artery grafts [area under curve: 0.758, 95%CI (0.694, 0.820); net reclassification index: 0.272, 95%CI (0.180, 0.370); comprehensive discriminative improvement index: 0.109, 95%CI (0.059, 0.158); P<0.05]. The risk score of independent risk factors for internal mammary artery graft failure demonstrated significant MACCE risk stratification efficiency in the 5-year patient follow-up, with the high-risk group showing a significantly higher incidence of MACCE compared to the medium and low-risk groups (P=0.001). ConclusionQFR>0.80, PI>3.0, non-left main lesions, and in-hospital complications are independent risk factors for early failure of internal mammary artery grafts after CABG. The constructed risk prediction model based on this has preliminary capabilities in predicting the risk of internal mammary artery graft failure and MACCE risk stratification, which is beneficial for the postoperative management of CABG patients and improving their mid-long term prognosis.
ObjectiveTo investigate the feasibility and effectiveness of using ultrasound to evaluate the internal mammary artery (IMA) and explore the related factors affecting the quality of IMA.MethodsFrom July 2020 to January 2021, for patients who underwent coronary artery bypass grafting at the Department of Cardiovascular Surgery, Fuwai Hospital, ultrasound was applied to measure bilateral IMA at the parasternal second intercostal space. There were 62 males and 18 females with an average age of 59.9±8.3 years. The clinical data of the patients were recorded and analyzed.ResultsA total of 160 IMA were measured. The IMA was detected in 99.4% (159/160), and the one that was not measured was proved to be occluded by enhanced CT. A total of 157 (98.1%) IMA intima were smooth, 2 (1.3%) were found to have uneven intimal thickening and less smooth, and only 1 (0.6%) was occluded. The intravascular diameter, peak systolic flow rate, peak diastolic flow rate, and blood flow rate of the left second intercostal IMA were 1.9±0.3 mm, 66.8±17.7 cm/s, 6.4 (0.0, 9.7) cm/s, 19.7±9.4 mL/min; and those of the right one were 2.1±0.3 mm, 69.7±18.5 cm/s, 6.0 (0.0, 9.2) cm/s and 22.8±11.5 mL/min, respectively. IMA vessel diameter and blood flow were greater on the right than those on the left side in the same individual (P<0.01). In univariate analysis, sex and body surface area were the factors that influenced the size of the IMA vessel among different individuals, and by linear regression analysis, the size of the IMA vessel was only related to body surface area among different individuals. On univariate analysis, diabetes mellitus was the only factor affecting IMA blood flow, with a mean reduction in blood flow of 18.4% (left) and 21.7% (right) in the diabetic group (P<0.05).ConclusionPreoperative evaluation of the IMA using ultrasound over the parasternal second intercostal space is easy, noninvasive, and has a high success rate. The internal diameter of the IMA is positively correlated with body surface area, and blood flow is significantly reduced in patients with diabetes.
Objective To study the method to inhibit perioperative internal mammary artery (IMA) spasm from the perspective of muscarinic receptor, and research the function of muscarinic cholinergic receptor subtypes of IMA. Methods IMA segments in vitro with intact endothelium were obtained from 30 patients who underwent coronary artery bypass grafting (CABG). According to muscarinic receptor antagonists of different concentrations， They were divided into control group (not using receptor antagonist), atropine group (nonselective M receptor antagonist), pirenzepine group (M1 receptor antagonist) and Methoctramine group(M2 receptor antagonist) by random number table. The effects of antagonists on vasodilatation were analyzed, Scott ratio was used to calculate affinity index (pD2) and Schild plot was used to count rivalry index (pA2). Results Acetylcholine (Ach)induced concentrationdependentrelaxation response of IMA segments with intact endothelium precontracted with potassium chloride (KCl). The pD2 was 6.92±0.05. The effects of atropine, pirenzepine and methoctramine on doseresponse curve induced by Ach with intact endothelium were all concentrationdependent. With the increase of the concentration of antagonists, the Achinduced doseresponse curves had a significant shift to right(Plt;0.05). Atropine, pirenzepine and Methoctramine competitively antagonized the reaction of vessel to Ach. The pA2 were 9.62±0.15,7.70±0.08 and 630±0.08, respectively. Conclusion The Achinduced relaxation response of IMA with intact endothelium is concentrationdependent. According to the affinity of different antagonist, IMA in Vitro Achinduced relaxation response is implemented by acting on nonneuronal muscarinic cholinergic M1 receptor subtype.
Objective To analyze the mean flow in left internal m am mary artery ( L IMA) graft and the influencing factors in off- pump coronary artery bypass grafting ( OPCAB) in the Chinese. Methods One hundred and eighty patients with OPCAB were studied.Transit- tim e flowmeter( TTFM) was utilized to measure and record the L IMA’s blood flow wave,pulsatility index( PI) ,value of mean flow,systolic and diastolic peak flow,vascular resistance,insufficiency ratio and mean blood pressure and to analyze the relationship between mean flow of LIMA and other factors. Results Total mean flow calculated from that of all patients was2 8.19± 2 .89ml/ min( 6 - 178 ml/ m in) .Majority m ean value ( 6 4 .4 % ) was in the range of 10 - 30 ml/ min.Statistics showed that mean flow was significantly related to systolic and diastolic peak flow and vascular resistance rather than the other factors( r=0 .75 , 0 .94 ,- 0 .95 ) . Conclusions For the Chinese,over 10 ml/ min mean flow of L IMA graftis acceptable and ov...更多er 2 2 ml/ min is satisfactory.The diastolic peak flow and vascular resistance are two most important factors in influencing mean flow.
ObjectiveTo introduce the method and preliminary experience of robot-assisted bilateral internal mammary arteries (BIMA) harvesting for off-pump coronary artery bypass grafting (OPCAB) with 5 grafts via left anterolateral minithoracotomy.MethodsBIMA were harvested using the da Vinci robotic surgical system, and the right internal mammary artery (RIMA) was pulled out of the thoracic cavity through right second intercostal space. Intercepting the distal part of the RIMA for the BIMA composite Lima-Rima Y graft and anastomosing the great saphenous vein with remaining RIMA end to end. The Y graft anastomosed with left anterior descending (LAD) branch and diagonal branches (DIAG), artery-vein graft sequentially anastomosed with blunt round branch, left ventricular posterior branch and posterior descending branch.ResultsThe operation succeeded without hemodynamic instability and intra aortic balloon pump (IABP) implantation or cardiopulmonary bypass. The blood flow of Y graft was 24 mL/min, and the blood flow of artery-vein graft was 30 mL/min. Ventilator assistance time was 35 hours, ICU staying time was 62 hours, and postoperative myocardial enzymes increased temporarily. Postoperative coronary CTA showed that all the grafts were patency, and cardiac ultrasound indicated that the heart function was normal. The patient cured and discharged from hospital 7 days after operation.ConclusionRobot-assisted bilateral internal mammary artery harvesting for OPCAB with 5 grafts via left anterolateral minithoracotomy is feasible, which can achieve complete revascularization.