[Fifteen-year results of bilateral and unilateral internal mammary artery grafting]. / Pyatnadtsatiletnie rezul'taty revaskulyarizatsii miokarda s ispol'zovaniem dvukh i odnoi vnutrennei grudnoi arterii.

OBJECTIVE: To evaluate the clinical effectiveness of bilateral internal mammary artery grafting over long-term (15 years) postoperative period. MATERIAL AND METHODS: There were 276 patients divided into two groups: 135 patients (group A) underwent bilateral internal mammary artery grafting and 141 patients (group B) underwent unilateral internal mammary artery grafting together with venous bypass grafts. On-pump surgeries and cardioplegia, parallel CPB and on-pump procedures were performed in equal proportions. Mean age of patients was 57.3±7.6 years. Diabetes mellitus was detected in 21 (15.5%) and 24 (19.1%) patients, respectively (p>0.05). Mean LV ejection fraction was 55.4±9.9%, revascularization index - 3.1±0.8 and 3.0±0.7, respectively. In the 1st group, 43 patients underwent bilateral internal mammary artery grafting alone. Autovenous grafts were additionally used in other 84 patients. RESULTS: Ten-year survival exceeded 90% in both groups. Freedom from adverse cardiac events after 15 years was significantly higher in group A (77.3% vs. 59.3%, p=0.018). In group A, 16 patients died throughout this period due to cancer (50%), myocardial infarction (12.5%), stroke (18.8%) and complications of diabetes mellitus (6.3%). In group B, 22 patients died mainly from cardiac causes (myocardial infarction - 40.9%, cancer - 27.3%). CONCLUSION: Bilateral internal mammary artery grafting has obvious advantages over traditional coronary artery bypass grafting. If we take into account higher proportion of cardiac causes in structure of mortality in group B, we can talk about positive impact of bilateral internal mammary artery grafting not only on the quality of life, but also on life expectancy in long-term postoperative period.

Why Are We Weighting? Understanding the Estimates From Propensity Score Weighting and Matching Methods.

BACKGROUND: Propensity score methods are used in observational studies to compensate for the lack of random allocation by balancing measured baseline characteristics between treated and untreated patients. We sought to explain the treatment effect estimates derived from different propensity score methods. METHODS: We performed a retrospective analysis of long-term mortality after single internal mammary artery versus bilateral internal mammary artery (BIMA) conduit in 47 984 index isolated coronary artery bypass grafting procedures from 1992 to 2014 in the Northern New England Cardiovascular Disease Study Group registry using multivariable Cox regression, 1:1 propensity score matching, inverse probability weighting (IPW) among the treated, and IPW among the overall population treatment estimates. RESULTS: The mean duration of follow-up was 13.2 (interquartile range, 7.4-17.7) years. In multivariable Cox regression, the adjusted hazard ratio for mortality was 0.83 (95% CI, 0.75-0.92) in patients receiving BIMA compared with a single internal mammary artery. The 1:1 propensity matched (hazard ratio, 0.79 [95% CI, 0.69-0.91]) and IPW among the treated (hazard ratio, 0.83 [95% CI, 0.75-0.92]) estimates showed a protective treatment effect of BIMA use on mortality. However, the IPW estimate of treatment effect for the overall population showed an increased risk of mortality after BIMA that was not statistically significant (hazard ratio, 1.08 [95% CI, 0.94-1.24]). CONCLUSIONS: While the multivariable Cox regression, 1:1 propensity matching, and IPW treatment effect in the treated estimates demonstrate that BIMA was associated with a statistically significantly decreased risk of mortality, the IPW treatment effect in the average study population showed an increased risk of mortality associated with BIMA that was not statistically significant. This is attributed to the different populations (weighted to look like the overall study population versus treated group) represented by the 2 IPW approaches. Determining how the study population is balanced is a large driver of the treatment effect. Ultimately, the treatment effect estimate desired should drive the choice of the propensity score method.

Long-Term Radial Artery Grafts with Previous Midterm Proven Patency.

INTRODUCTION: Left internal thoracic artery to left anterior descending artery (LITA-LADA) grafting has become a fundamental part of coronary artery bypass grafting (CABG). This grafting has led to an increased use of other arterial conduits, of which the radial artery (RA) is the most popular. Whether RA can have the same long-term patency as LITA is controversial. The objective of this study is to access the long-term clinical follow-up and, when available, the patency rate of RA grafts. METHODS: Twenty-six patients from a previous study with critical stenosis in all target vessels underwent complete arterial CABG with LITA and RA grafts from 1996 to 2003. They all underwent midterm multidetector computed tomography after surgery with the association of at least one patent LITA and one patent RA graft. RESULTS: Twelve patients (46%) are alive with no angina symptoms. Six patients underwent a second image exam 12 to 16 years (average of 14 years) after surgery, with a total of six LITA-LADA and 14 RA grafts with 100% patency rate. Clinical follow-up five to 23 years after surgery (average of 14 years) showed only one death 12 years after surgery related to coronary artery disease (CAD) (3,8%). Another 12 patients died of non-CAD. CONCLUSION: Patients with midterm associated LITA and RA patent grafts show similar optimal long-term patency rates of both types of grafts with excellent clinical outcome.

Metformin and empagliflozin modulate monoamine oxidase-related oxidative stress and improve vascular function in human mammary arteries.

Monoamine oxidases (MAOs), mitochondrial enzymes with two isoforms, A and B, have been recently recognized as significant contributors to oxidative stress in the cardiovascular system. The present study was purported to assess the effect of metformin and empagliflozin on MAO expression, oxidative stress and vascular reactivity in internal mammary arteries harvested from overweight patients with coronary heart disease subjected to bypass grafting. Vascular rings were prepared and acutely incubated (12 h) with high glucose (GLUC, 400 mg/dL) or angiotensin II (AII, 100 nM) and metformin (10 µM) and/or empagliflozin (10 µM) and used for the assessment of MAO expression (qRT-PCR and immune histochemistry), reactive oxygen species (ROS, confocal microscopy and spectrophotometry), and vasomotor function (myograph). Ex vivo stimulation with GLUC or AII increased both MAOs expression, ROS production and impaired relaxation to acetylcholine (ACh) of the vascular rings. All effects were alleviated by incubation with each antidiabetic drug; no cumulative effect was obtained when the drugs were applied together. In conclusion, MAO-A and B are upregulated in mammary arteries after acute stimulation with GLUC and AII. Endothelial dysfunction and oxidative stress were alleviated by either metformin or empagliflozin in both stimulated and non-stimulated vascular samples harvested from overweight cardiac patients.

Long-Term Radial Artery Grafts with Previous Midterm Proven Patency

ABSTRACT Introduction: Left internal thoracic artery to left anterior descending artery (LITA-LADA) grafting has become a fundamental part of coronary artery bypass grafting (CABG). This grafting has led to an increased use of other arterial conduits, of which the radial artery (RA) is the most popular. Whether RA can have the same long-term patency as LITA is controversial. The objective of this study is to access the long-term clinical follow-up and, when available, the patency rate of RA grafts. Methods: Twenty-six patients from a previous study with critical stenosis in all target vessels underwent complete arterial CABG with LITA and RA grafts from 1996 to 2003. They all underwent midterm multidetector computed tomography after surgery with the association of at least one patent LITA and one patent RA graft. Results: Twelve patients (46%) are alive with no angina symptoms. Six patients underwent a second image exam 12 to 16 years (average of 14 years) after surgery, with a total of six LITA-LADA and 14 RA grafts with 100% patency rate. Clinical follow-up five to 23 years after surgery (average of 14 years) showed only one death 12 years after surgery related to coronary artery disease (CAD) (3,8%). Another 12 patients died of non-CAD. Conclusion: Patients with midterm associated LITA and RA patent grafts show similar optimal long-term patency rates of both types of grafts with excellent clinical outcome.

Uncommon Cause of Internal Mammary Artery Pseudoaneurysm.

Background: Internal mammary artery pseudoaneurysms most commonly develop from thoracic penetrating trauma or procedures. However, other important etiologies should not be overlooked. Case Report: A 27-year-old female presented with antiphospholipid antibody syndrome, thrombotic microangiopathy, end-stage renal disease on hemodialysis, and epilepsy. On admission, the patient had pulseless electrical activity and hypertensive emergency. After the patient was successfully resuscitated, she developed status epilepticus. Laboratory workup on admission revealed a subtherapeutic international normalized ratio, elevated C-reactive protein and sedimentation rate, and acute anemia. Imaging showed a right-sided subdural hematoma with a midline shift and likely internal mammary artery pseudoaneurysm. Angiography demonstrated aneurysmal dilation, segmental narrowing, and a string of beads appearance. Because of our patient's demographics, string of beads appearance on diagnostic angiography, history of renal disease, and negative hepatitis serology, fibromuscular dysplasia was considered the etiology of the internal mammary artery pseudoaneurysm. The family opted for 2 burr holes and a subdural drain but declined further diagnostic and therapeutic interventions because of anoxic brain injury and poor prognosis. Conclusion: In this patient, the etiology of the internal mammary artery pseudoaneurysm was attributed to fibromuscular dysplasia. Although this patient's family chose comfort measures, treatment methods are available for internal mammary artery pseudoaneurysms.

Excessive Adventitial and Perivascular Vascularisation Correlates with Vascular Inflammation and Intimal Hyperplasia.

Albeit multiple studies demonstrated that vasa vasorum (VV) have a crucial importance in vascular pathology, the informative markers and metrics of vascular inflammation defining the development of intimal hyperplasia (IH) have been vaguely studied. Here, we employed two rat models (balloon injury of the abdominal aorta and the same intervention optionally complemented with intravenous injections of calciprotein particles) and a clinical scenario (arterial and venous conduits for coronary artery bypass graft (CABG) surgery) to investigate the pathophysiological interconnections among VV, myeloperoxidase-positive (MPO+) clusters, and IH. We found that the amounts of VV and MPO+ clusters were strongly correlated; further, MPO+ clusters density was significantly associated with balloon-induced IH and increased at calciprotein particle-provoked endothelial dysfunction. Likewise, number and density of VV correlated with IH in bypass grafts for CABG surgery at the pre-intervention stage and were higher in venous conduits which more frequently suffered from IH as compared with arterial grafts. Collectively, our results underline the pathophysiological importance of excessive VV upon the vascular injury or at the exposure to cardiovascular risk factors, highlight MPO+ clusters as an informative marker of adventitial and perivascular inflammation, and propose another mechanistic explanation of a higher long-term patency of arterial grafts upon the CABG surgery.

Occurrence rate and fate of competitive flow of the left internal thoracic artery used in Y-composite grafts.

Objectives: We evaluated the occurrence rate of competitive flow and the fate of grafts of left internal thoracic artery (LITA)-to-left anterior descending coronary artery (LAD) anastomosis after coronary artery bypass grafting with Y-composite grafts using early and 1-year angiography. Methods: From 2008 to 2017, 923 patients underwent off-pump coronary artery bypass grafting using Y-composite grafting based on the in situ LITA. Early postoperative angiography was performed for all patients. One-year angiography (mean, 13.2 ± 3.1 months) was performed for 86.7% (800 of 923) of patients. Results: The early occlusion rate of LITA with Y-composite graft (CompLITA) to LAD was 0.7%. Among 917 patent CompLITA-LAD grafts, competitive flow was observed in 39 patients (4.3%). Multivariable analysis showed that the degree of LAD stenosis (odds ratio, 0.897; 95% CI, 0.875-0.920; P < .001) and 3-vessel disease (odds ratio, 5.632; 95% CI, 1.168-27.155; P = .031) were factors associated with the occurrence of competitive flow of CompLITA-LAD grafts. The receiver operating characteristics curve determined that the cutoff degree of LAD stenosis was 82.5% (sensitivity 82.1% and specificity 85.2%). The failure rate of CompLITA-LAD grafts seen on 1-year angiography was 58.3% in patients with competitive flow. Among patients with competitive flow, left main coronary artery disease was a protective factor (odds ratio, 0.055; 95% CI, 0.009-0.337; P = .002) against graft failure of the CompLITA-LAD seen on 1-year angiography. Conclusions: In CompLITA-LAD, the degree of LAD stenosis and combined 3-vessel disease were associated with the occurrence of competitive flow. CompLITA-LAD grafts with early competitive flow showed a high 1-year graft failure rate of 58%.

Techniques and Outcomes of the No-Touch Vein Conduit as a Y-Composite Graft.

Although the saphenous vein is a widely used conduit for coronary artery bypass grafting, revascularization using the saphenous vein as an aortocoronary bypass graft has shown disadvantages of lower long-term graft patency rates and subsequently worse clinical outcomes, compared with revascularization using the internal thoracic artery. Of the various efforts to overcome the limitations of vein conduit that are resulting from structural and functional differences from arterial conduit, recent technical improvement in no-touch vein composite graft construction and outcomes of revascularization using no-touch vein composite grafts based on the left internal thoracic artery will be discussed in this topic.

Impact of Single versus Double Clamp Technique on Blood Lactate Levels and Postoperative Complications in Coronary Artery Bypass Surgery

Abstract Introduction: Cardiopulmonary bypass (CPB) is associated with hyperlactatemia, which leads to adverse clinical outcomes. No study has examined the effect of different clamping techniques on postoperative hyperlactatemia (PHL). Thus, we aimed to evaluate the impact of two different techniques on PHL and the clinical outcomes in patients undergoing isolated coronary artery bypass surgery. Methods: This retrospective study included 100 patients who underwent isolated CPB either with single clamp technique (SCT, n=47) or double clamp technique (DCT, n=53). Demographic and preoperative laboratory data, as well as operative features and arterial blood lactate levels at the onset and at the end of CPB, were collected from patient charts. Results: Blood lactate levels collected at the end of CPB did not differ significantly between groups whereas intraoperative lactate increased significantly in both groups (P<0.005). PHL developed in 16 patients (32%). There was no meaningful difference in SCT and DCT in this regard. Left internal mammary artery was used more frequently in the DCT group than in the SCT group. While the cross-clamp time was significantly longer in the SCT group, there was no difference regarding CPB time. Among postoperative complications, only the incidence of stroke was significantly higher in the DCT group than in the SCT group (10.6% vs. 0%, P=0.020). CPB time, cross-clamp time and numbers of proximal saphenous graft and distal anastomosis showed a significant positive correlation with the postoperative lactate level. In the regression analysis, CPB time emerged as the only independent predictor of PHL (OR 1.04, CI 95% 1.01-1.07, P=0.011). Conclusion: There was no difference in postoperative blood lactate levels between SCT and DCT groups.

Hybrid robotic off-pump versus conventional on-pump and off-pump coronary artery bypass graft surgery in women.

OBJECTIVE: To compare outcomes of three methods of coronary artery bypass graft surgery (CABG): robotic off-pump hybrid coronary revascularization (HCR) versus conventional CABG off-pump (off-pump coronary artery bypass [OPCAB]) and on-pump (on-pump coronary artery bypass [ONCAB]) in women. METHODS: Data on women who underwent robotic off-pump HCR or conventional OPCAB or conventional ONCAB between May 2005 and January 2021 were collected. Inverse probability of treatment weighting (IPTW) with doubly robust method was used to analyze the data. RESULTS: A total of 731 women were included (181 robotic off-pump HCR, 138 conventional ONCAB, and 412 conventional OPCAB cases). IPTW-adjusted analyses revealed the following: (1) for operative times, robotic off-pump HCR presented longer times when compared with OPCAB, but shorter times when compared with ONCAB; (2) compared with ONCAB and OPCAB, robotic off-pump HCR presented lower rates of reintervention for bleeding, intra- and postoperative blood transfusions, higher rates of extubation in the OR with less prolonged ventilation, lower rates of postoperative atrial fibrillation, and shorter intensive care unit and hospital length of stay; (3) no statistically significant differences for operative mortality were observed comparing robotic off-pump HCR with ONCAB (IPTW-adjusted odds ratio [OR]: 0.77; 95% confidence interval [CI]: 0.07-7.85; p = .822) and with OPCAB (IPTW-adjusted OR: 4.27; 95% CI: 0.27-66.88; p = .301); 4. long-term survival was similar with HCR compared with ONCAB (hazard ratio [HR]: 0.74, 95% CI: 0.36-1.50, p = .401) and OPCAB (HR: 0.89, 95% CI: 0.50-1.58, p = .683). CONCLUSIONS: In our local experience, robotic off-pump HCR in women was as safe as conventional ONCAB and OPCAB and may further improve postoperative outcomes when performed frequently by a dedicated team, producing better perioperative outcomes without compromising survival in the long run.

Impact of Single versus Double Clamp Technique on Blood Lactate Levels and Postoperative Complications in Coronary Artery Bypass Surgery.

INTRODUCTION: Cardiopulmonary bypass (CPB) is associated with hyperlactatemia, which leads to adverse clinical outcomes. No study has examined the effect of different clamping techniques on postoperative hyperlactatemia (PHL). Thus, we aimed to evaluate the impact of two different techniques on PHL and the clinical outcomes in patients undergoing isolated coronary artery bypass surgery. METHODS: This retrospective study included 100 patients who underwent isolated CPB either with single clamp technique (SCT, n=47) or double clamp technique (DCT, n=53). Demographic and preoperative laboratory data, as well as operative features and arterial blood lactate levels at the onset and at the end of CPB, were collected from patient charts. RESULTS: Blood lactate levels collected at the end of CPB did not differ significantly between groups whereas intraoperative lactate increased significantly in both groups (P<0.005). PHL developed in 16 patients (32%). There was no meaningful difference in SCT and DCT in this regard. Left internal mammary artery was used more frequently in the DCT group than in the SCT group. While the cross-clamp time was significantly longer in the SCT group, there was no difference regarding CPB time. Among postoperative complications, only the incidence of stroke was significantly higher in the DCT group than in the SCT group (10.6% vs. 0%, P=0.020). CPB time, cross-clamp time and numbers of proximal saphenous graft and distal anastomosis showed a significant positive correlation with the postoperative lactate level. In the regression analysis, CPB time emerged as the only independent predictor of PHL (OR 1.04, CI 95% 1.01-1.07, P=0.011). CONCLUSION: There was no difference in postoperative blood lactate levels between SCT and DCT groups.

Techniques and Outcomes of the No-Touch Vein Conduit as a Y-Composite Graft

ABSTRACT Although the saphenous vein is a widely used conduit for coronary artery bypass grafting, revascularization using the saphenous vein as an aortocoronary bypass graft has shown disadvantages of lower long-term graft patency rates and subsequently worse clinical outcomes, compared with revascularization using the internal thoracic artery. Of the various efforts to overcome the limitations of vein conduit that are resulting from structural and functional differences from arterial conduit, recent technical improvement in no-touch vein composite graft construction and outcomes of revascularization using no-touch vein composite grafts based on the left internal thoracic artery will be discussed in this topic.

Graft flow analysis of application of bilateral internal mammary artery with different configurations in coronary artery bypass grafting / 中华胸心血管外科杂志

Objective:To analyze the influence of application of bilateral internal mammary artery(BIMA) with different configurations in coronary artery bypass grafting(CABG).Methods:From January 2018 to December 2020, 82 patients underwent CABG using BIMA were included, with 75 males and 7 females, aged(56.9±9.8) years old. According to the target of coronary artery of BIMA, patients were divided into two groups, 23 patients(group B) who underwent the traditional operation(RIMA to the right coronary artery), and 59 patients(group L) whose RIMA were grafted to the left ventricular arteries. Also the patients were divided into two groups according to the RIMA used either in situ(group I, 57 cases) or free(group F, 25 cases). Compare the grafts flow between groups. The CTA angiography of coronary artery was completed to evaluate the grafts patency before discharge.Results:There was 1 early operative death(1.22%). The mean flow(MF) of RIMA was significantly higher in group B( P=0.013). The pulsatility index(PI) of LIMA was significantly lower and the MF of RIMA and BIMA was higher(all P<0.05), fewer patients with LIMA-MF less than 15 ml/min( P=0.023)in the group I. CTA angiography before discharge showed that only 1 RIMA to right coronary artery was occlusion. Conclusion:It is better to use BIMA in situ in CABG, RIMA used in right coronary artery can receive more satisfactory graft flow. BIMA has good patency in early stage, therefore is the ideal and stable coronary bypass graft.

Patients Submitted to Myocardial Revascularization with the Use of Bilateral Internal Thoracic Arteries: Diabetics vs. Non-Diabetics

Abstract Introduction: Use of bilateral internal thoracic artery (BITA) as graft in coronary artery bypass grafting (CABG) is controversial because it is related to higher in-hospital mortality, incidence of sternal wound-related infection, and an increase in surgical time. The primary objective of this study is to evaluate in-hospital mortality and mortality within 30 days from discharge. The secondary objective is to evaluate the occurrence of deep sternal wound infection in a 90-day follow-up. Methods: This is a retrospective review of the medical records of 152 patients undergoing elective CABG with the use of BITA and cardiopulmonary bypass (CPB). These patients were divided into two groups, diabetics and non-diabetics. Patients with acute myocardial infarction and concomitant valvular disease were not included in the sample. Results: Preoperative characteristics did not show significant differences between the groups, which allowed a comparative analysis. The variables electrocardiography time and aortic clamping time were higher in the diabetic group, with a significant statistical difference (P<0.0001). In-hospital mortality occurred in three patients, and there was no mortality up to 30 days in both groups. There was no significant difference in the primary end point between groups (P=0.56). Deep sternal wound infection was present in only one patient and showed no significant difference in the secondary outcome between groups (P=0.40). Conclusion: We did not observe a higher mortality and occurrence of deep sternal wound infection with the use of BITA in diabetic patients compared to non-diabetics, even with greater CPB and aortic clamping times in diabetics.