Mammary Graft Research Articles

Is it possible to augment myocardial protection during cardiopulmonary bypass by administration of inhalational anesthetics?

Aim: To evaluate the possibility to augment myocardial protection with desflurane and sevoflurane by prolongation of their delivery into the oxygenator of the cardiopulmonary bypass (CPB) pump during surgical myocardial revascularization.Materials and methods: This randomized prospective study included 75 patients with ischemic heart disease who underwent aortocoronary and mammary coronary bypass grafting with extracorporeal circulation from 2014 to 2017. The patients were allocated into the three study group by means of a random number table generated by Statistica 10.0 software, depending on the anesthetic agent used: group 1, desflurane (n=30), group 2, sevoflurane (n=28), and group 3 (control), propofol (n=17). Desflurane and sevoflurane were delivered into the oxygenator during the artificial circulation. Hemodynamic parameters were assessed, such as cardiac index, total peripheral vascular resistance index, pulmonary artery wedge pressure. Changes in lactate, pyruvate, alanine, glutamate, glutamine, aspartate, asparagine, taurine, leucine, isoleucine and valine levels over time were assessed in blood taken from the heart coronary sinus before aortal clamping, before release of the clamp and after 30 minutes of reperfusion. During the first 24 hours post perfusion, we assessed the incidence of postperfusion heart failure (PPHF), duration of mechanical ventilation and duration of stay in the intensive care unit. Troponin I levels were measured at 12 and 24 hours after the intervention.Results: There were no significant differences in the changes of the hemodynamic parameters over time in all the groups. The PPHF incidence and the course of the postoperative period were similar in all the groups. Irrespective on the type of the anesthesia, lactate and pyruvate levels increased during the CPB, with no significant differences between the groups, as well as the postoperative troponin I levels at 12 and 24 hours after surgery. No differences between the groups were found for the changes of amino acid levels over time, except a significant reduction of alanine levels during the aortal clamp in the group 3.Conclusion: Prolongation of desflurane and sevoflurane delivery into the CPB pump oxygenator does not augment myocardial protection during myocardial revascularization surgery.

Occluded mammary graft post-coronary bypass surgery: do we need to look for the second one? A case report.

BackgroundAnatomic variations of the left internal mammary artery (LIMA) can influence coronary artery bypass surgical technique as well as posing definite difficulties in the interpretation of angiographic findings. We present an unusual anatomic variant of two LIMAs originating from the left subclavian artery discovered post-coronary artery bypass grafting surgery.Case summaryA 60-year-old man post-LIMA grafting of the left anterior descending (LAD) coronary artery underwent diagnostic cardiac catheterization. Selective angiography revealed occluded LIMA; therefore, it was decided to proceed with percutaneous coronary intervention (PCI) to the occluded native LAD. Once antegrade flow in the LAD was restored, retrograde filling of a vessel corresponding to the previously grafted LIMA was also detected. Additional contrast injection in the left subclavian artery (LSCA) showed a second patent LIMA originating from the distal segment of the LSCA.DiscussionThis patient has an unusual anatomic variant of two LIMAs originating from the LCSA. The proximal rudimentary LIMA was misinterpreted as an occluded arterial graft while the second, well-developed LIMA connected to the LAD had an unusually distal origin and had therefore been overlooked. This anatomical variant should be kept in mind when the internal mammary graft seems to be occluded.

225Ac-NM600 Targeted Alpha Therapy Extends Survival in a Model of Triple Negative Breast Cancer

Triple negative breast cancer (TNBC) remains the most lethal breast cancer histology. Currently, approved targeted therapies for TNBC do not exist, and novel tumor-targeted interventions to complement/supplant the current standard of care using chemotherapy are urgently needed [1]. Our research group has developed a series of tumor-avid alkyphosphocholine analogs (APC) that can carry a radiolabel for both imaging and targeted radionuclide therapy of breast cancer. In this study we investigated the potential of NM600, our lead APC analog, radiolabeled with the alpha emitter 225Ac, for targeted alpha therapy (TAT) in a mouse model of TNBC. Radiolabeling yields were nearly quantitative (>95%) with a specific activity of 3.4 GBq/μmol. Excipient and serum stability of 225Ac-NM600 at 8 days was 90% and 95%, respectively. Longitudinal ex vivo biodistribution studies were performed in Balb/C mice bearing mammary adenocarcinoma 4T1 tumor grafts injected with 20 kBq 225Ac-NM600 at 4, 24, 48, 96, and 216 h post injection (p.i.). Elevated radioactivity was observed in the blood (15.2 ± 1.2 %ID/g) at 4 h p.i. and gradually declined overtime with a 23.1 ± 1.9 h biological half live (n = 3). Due to the hepatobiliary excretion of 225Ac-NM600, distribution in normal tissue was most prominent in the liver, peaking at 28.1 ± 3.6 %ID/g at 96 h p.i. 225Ac-NM600 uptake in 4T1 tumors progressively increased from 6.7 ± 3.0 %ID/g at 4 h to 26.1 ±15.6 %ID/g (n = 3) at the final timepoint, 216 h p.i.. Biodistribution did not change when 225Ac-NM600 was administered with a 50-fold lower specific activity. In therapy studies, three groups of mice bearing 4T1 tumors (∼150 mm3, n = 5) were administered either excipient (control), 20 kBq, or 40 kBq 225Ac-NM600, and tumor progression and animal survival were monitored for 60 days. Significant tumor regression (P < 0.001) was observed in both treatment arms compared to control within a week following treatment; however, a survival benefit was only achieved in the 20 kBq group, in which all mice showed controlled disease and no signs of acute toxicity. The administration of 40 kBq was acutely radiotoxic. These preliminary results demonstrate the potential of TAT using NM600 for the treatment of TNBC and warrant further treatment optimization and the exploration of potential long-term toxicities. [1]Bianchini, G., et al., Triple-negative breast cancer: challenges and opportunities of a heterogeneous disease. Nat Rev Clin Oncol, 2016. 13(11): p. 674-690.

Management of Paravalvular Leak After Rapid Deployment Edwards Intuity Elite Valve

A 74-year-old man with a past medical history of diabetes mellitus, hypertension, severe aortic stenosis, coronary artery disease status post-coronary artery bypass surgery with left internal mammary artery, vein graft, and aortic valve replacement with a Rapid Deployment Edwards 23-mm Intuity Elite

OC62 REDO MITRAL SURGERY AND HOSPITAL OUTCOME: IMPACT OF FAILED MITRAL VALVE REPAIR

Background and Aim: Mitral valve repair is the gold standard for mitral valve regurgitation, even if failed mitral repairs (FMR) have been reported. The aim of this study was to evaluate the impact of FMR on early outcome after redo mitral surgery. Methods: Operative mortality and major morbidity events from 920 redo mitral procedures at nine European centres were analysed. Statistical analysis was performed by the SPSS 13.0 program for Windows (SPSS, Inc., Chicago, IL, USA). To identify indipendent predictors of operative deaths, variables with a P &lt; 0.10 at univariable analysis were included in the regression models. All the outcome parameters were then adjusted by propensity matching, to compare similar cohorts of patients with FMR or diseased native mitral valves and similar cohorts of patients with FMR and malfunctioning prostheses. Results: FMR did not impact mortality at multivariable analysis (P = 0.64). Propensity-matched cohorts of FMR and native mitral valves showed no differences in mortality (P = 0.69). A preoperative Global Initiative for Chronic Obstructive Lung Disease score &gt;2 chronic lung disease (COPD) (OR 15.2, P &lt; 0.01), left ventricular ejection fraction &lt;30% (odds ratio (OR) 21.5, P = 0.005), major injury to cardiovascular structures at re-entry (OR 27.2, P &lt; 0.01) or to patent left internal mammary artery-coronary artery bypass graft (OR 7.6, P = 0.03) predicted mortality in the FMR population. Conclusions: A failed mitral repair does not impact hospital outcome of redo surgery. Severe left ventricular dysfunction, COPD and injury at re-entry predict adverse early outcome.

P4567Do women benefit from bilateral internal mammary artery bypass grafting?

P4567Do women benefit from bilateral internal mammary artery bypass grafting?

P2694Long-term outcome after myocardial revascularisation by bilateral mammary grafting

P2694Long-term outcome after myocardial revascularisation by bilateral mammary grafting

Surgical left subclavian artery revascularization for thoracic aortic stent grafting: a single-centre experience in 101 patients.

To evaluate the indications, perioperative strategy and postoperative outcome of surgical left subclavian artery (LSA) revascularization combined with thoracic endovascular aortic repair (TEVAR) covering the LSA. Between 2000 and 2017, a total of 101 consecutive patients underwent surgical revascularization of the LSA prior to, concomitant or following TEVAR. Revascularization was performed through a small supraclavicular incision and consisted of a transposition or bypass graft, using intraoperative transcranial Doppler monitoring. Data regarding indication, procedural details and postoperative results were retrospectively analysed. In total, 63 subclavian-carotid bypass grafts and 38 subclavian-carotid transpositions were performed in the context of TEVAR. The majority was performed prior to stent grafting to reduce the risk of stroke (n = 50), spinal cord ischaemia (n = 20), left arm malperfusion (n = 10) or to preserve a patent left internal mammary artery coronary bypass graft (n = 2). Secondary revascularization was performed in 14 patients, 2 times immediately due to acute left arm malperfusion and 12 times to treat invalidating left arm claudication. No in-hospital mortality and permanent spinal cord ischaemia occurred. Two (2%) ischaemic strokes were observed in patients with concomitant procedures, and none when separate, staged procedures were performed. Additional complications observed were permanent peripheral nerve palsies (9%), chyle leakage requiring diet (6%) and 1 bypass occlusion requiring a redo procedure. In patients predominantly selected upon the anticipated risk of (posterior) stroke, spinal cord ischaemia and left arm malperfusion, surgical revascularization of the LSA proved to be a safe treatment option to preserve antegrade LSA flow in the context of TEVAR.

Bilateral versus single internal mammary artery bypass grafts for coronary arterial atherosclerosis

Bilateral versus single internal mammary artery bypass grafts for coronary arterial atherosclerosis

Bilateral Internal Mammary Artery Bypass Grafting: Sternal Wound Infection in High-Risk Population. Should Sternal Infection Scare Us?

Background:Bilateral internal mammary arteries (BIMAs) remain underused in coronary artery bypass grafting (CABG), especially in elderly, diabetic, and obese patients. This study investigated incidence of sternal wound infection (SWI), sternal instability (SI), and reintervention for bleeding (RIB) in this high-risk population.Methods:A single-center retrospective observational study was performed in “Grand Hôpital de Charleroi, Gilly, Belgium.” A total of 319 patients undergoing CABG from December 2011 to December 2015 were included. Three main outcome measures (SWI, SI, and RIB) were investigated in obese vs nonobese, diabetic vs nondiabetic, and elderly vs younger patients.Results:In all, 14 SWI, 11 SI, and 6 RIB were discounted. Death rate was as follows: SWI: 2/14 vs 17/305 (P = .178), SI: 2/11 vs 17/308 (P = .081), and RIB: 2/6 vs 17/313 (P = .004). In obese (n = 113) vs nonobese (n = 206) patients, there was no difference for SWI (P = .263), SI (P = .565), and RIB (P = .332). In diabetic (n = 118) vs nondiabetic (n = 201) patients, there was no difference for SWI (P = .642), SI (P = .497), and RIB (P = .298). In elderly (n = 62) vs younger (n = 257) patients, there was no difference for SWI (P = .619), SI (P = .915), and RIB (P = .385).Conclusions:Obesity, age, and diabetes treated by insulin (or not) do not seem to be risk factors for developing SWI, SI, or RIB in patients receiving a CABG using BIMA. Nevertheless, mortality was higher in RIB group.

Decreased FENDRR and LincRNA-p21 expression in atherosclerotic plaque.

Objective:Cardiovascular diseases are the most important cause of mortality worldwide, particularly atherosclerosis. Recently, lncRNAs affecting atherosclerotic progression have been reported in vascular smooth muscle cells, endothelial cells, and monocytes, suggesting that lncRNAs play an important role in atherosclerosis.Methods:In recent clinical studies, nowadays, it was determined that internal mammary bypass grafts are closest to ideal grafts in coronary artery bypass surgery. In this study, we used tissue samples taken from atherosclerotic coronary arteries and the internal mammary artery (IMA) during coronary artery bypass surgery. Using RT-PCR, we investigated the role of two lncRNAs, FENDRR and LincRNA-p21, by comparing their expression levels in coronary artery plaques and normal mammary arteries of 20 atherosclerotic patients.Results:We found that the FENDRR and LincRNA-p21 expressions decreased by approximately 2 and 7 fold in coronary artery plaques, respectively, compared with those in IMA, which is known to have no plaque development.Conclusion:This study was the first to use mammary artery tissues of the same patients as a control and to study FENDRR expression. Our data may provide helpful insights regarding the association of lncRNAs and atherosclerosis.

Late Survival of Left Internal Mammary Artery-Radial Artery-Y Graft Compared to Single Internal Mammary Artery and Saphenous Vein Grafts in Coronary Bypass Surgery

Late Survival of Left Internal Mammary Artery-Radial Artery-Y Graft Compared to Single Internal Mammary Artery and Saphenous Vein Grafts in Coronary Bypass Surgery

High-Output Cardiac Failure and Coronary Steal With an Arteriovenous Fistula

Creation of an arteriovenous access for hemodialysis can provoke a sequence of events that significantly affects cardiovascular hemodynamics. We present a 78-year-old man with end-stage renal disease and concomitant coronary artery disease previously requiring coronary artery bypass grafting including a left internal mammary graft to the left anterior descending artery, ischemic cardiomyopathy with left ventricular systolic dysfunction, and severe aortic stenosis who developed hypotension unresponsiveto medical therapy after recent angioplasty of his ipsilateral arteriovenous fistula for high-grade outflow stenosis. This case highlights the long-term effects of dialysis access on the cardiovascular system, with special emphasis on complications such as high-output cardiac failure and coronary artery steal syndrome. Banding of the arteriovenous fistula provided symptomatic relief with a decrease in cardiac output. Avoidance of arteriovenous access creation on the ipsilateral upper extremity in patients with a left internal mammary artery bypass graft may prevent coronary artery steal syndrome.

Long-term Outcomes of Carotid-Subclavian Bypass in the Setting of Thoracic Endovascular Aortic Repair

Subclavian artery revascularization is frequently performed in the setting of thoracic endovascular aortic repair (TEVAR) for a variety of indications ranging from prophylactic prevention of upper extremity and spinal cord ischemia to preservation of hemodialysis access or left internal mammary artery coronary artery bypass graft. Despite this, there is little information on the short- and long-term outcomes of patients undergoing carotid to subclavian artery bypass. We sought to define the outcomes associated with this procedure. Patients undergoing carotid-subclavian bypass in conjunction with TEVAR between June 2005 and September 2016 were retrospectively identified from a prospectively maintained, single-center aortic surgery database. Categorical and continuous variables were compared using χ2 and Wilcoxon rank sum tests, respectively. The 30-day outcomes specific to the carotid-subclavian bypass procedure were analyzed, including nerve injury, bleeding complications, and local vascular complications. All preoperative and postoperative chest radiographs were carefully analyzed to assess for hemidiaphragm elevation indicative of phrenic nerve palsy. Long-term outcomes included primary graft patency and anastomotic complications. Of 579 patients undergoing TEVAR during this time interval, 114 patients (20%) underwent concomitant carotid-subclavian bypass. The cohort was 39% female (n = 44), with a mean age of 65 ± 14 years. The majority of conduits were 8-mm polytetrafluoroethylene grafts (n = 107 [92.2%]), with a minority being reversed saphenous vein grafts (n = 4 [3.5%]). The bypass procedure was done concomitantly at the time of TEVAR in 90.4% (n = 103) of cases. The short-term complication rate attributed specifically to the carotid-subclavian bypass was 21% (n = 24). These complications included neck hematoma requiring re-exploration in 0.9% (n = 1), recurrent laryngeal nerve palsy in 5.3% (n = 6), axillary nerve palsy in 1.8% (n = 2), and phrenic nerve palsy in 13.2% (n = 15) of patients. The 30-day all-cause mortality rate was 5.3% (n = 6), and the rate of permanent paraparesis or paraplegia was 0.9% (n = 1). Of the operative survivors (n = 108), follow-up imaging of the bypass graft was available in 84% (n = 96) of patients. Actuarial primary graft patency was 97% at 10 years (Fig). There were three patients (2.5%) with bypass graft occlusions, two of which were clinically silent and detected in follow-up imaging. The third was detected because of the symptoms of subclavian steal and required repeated revascularization. Two patients (1.8%) developed a late anastomotic pseudoaneurysm requiring either endovascular (n = 1) or surgical (n = 1) intervention. Carotid-subclavian bypass for revascularization of the subclavian artery performed in the setting of TEVAR is durable, although the true complication rate is likely to be higher than generally reported in the literature because of a not insignificant rate of phrenic nerve palsy. These data should serve well as “gold standard” comparison data for emerging branch graft devices.

ESTIMATION OF CARDIAC SURGERY RESULTS

Objective: Estimation of cardiac surgery results after median sternal incision.Methods: This work contains the results of surgical treatment of 220 patients who had cardiac surgeries performed by means of the median sternal incision at the State Healthcare Institution “Ulyanovsk Regional Clinical Hospital” during 2000–2014.Results: The following surgical interferences were made: Coronary artery bypass grafting – 14 (6.3%), mammary coronary bypass – 5 (2.3%), combined coronary artery and mammary coronary bypass grafting – 81 (36.8%), aortic valve replacement – 53 (24.1%), mitral valve replacement – 44 (20%), atrial septal defect plasty – 7 (3.2%), ventricular septal defect plasty – 3 (1.4%), myxomas – 5 (2.3%), and mediastinal neoplasms removal – 8 (3.6%). The most frequent early complications after median sternal incision were wound pyoinflammatory complications that were observed in 32 (14.5%) patients, pneumonia – defined in 17 (7.7%) patients, mediastinitis – found in 5 (2.3%) patients, sepsis – detected in 2 (0.9%) patients, and acute cerebrovascular disease – observed in 1 (0.5%) patient. The fatal outcome was observed in 2 (0.9%) cases; the cause of death of the first (0.5%) patient was multiple organ failure against the background of sepsis, and the cause of death of the second patient (0.5%) was acute cerebrovascular disease.Conclusion: The most frequent early post-operative complications the patients have after cardiac surgeries are wound pyoinflammatory complications (14.5%), pneumonia (7.7%), and mediastinitis (2.3%).

Robot-assisted totally endoscopic coronary bypass surgery

Totally endoscopic coronary artery bypass (TECAB) surgery can exclusively be undertaken with the aid of operative robots. In the past two decades, surgical remote manipulator systems—predominantly the daVinci® devices—have brought us the reality of endoscopic internal mammary artery harvesting and coronary bypass anastomoses via minimally invasive thoracic port access. Single up to quadruple TECAB interventions are recently feasible; the procedure can be delivered either as beating heart applying endoscopic vacuum stabilizer or under cardioplegic arrest on heart-lung machine. Significant surgical team learning curves are involved in a stepwise development of these complex procedures, including intense dry- and wet-lab trainings, endoscopic internal mammary artery harvesting and manual coronary anastomosis building through a thoracotomy. Increasing number of papers have been published regarding clinical TECAB series in the past decade. In arrested heart TECAB procedures on cardiopulmonary bypass, the conversion rate from port access to larger thoracic incision measures 15.1% and no perioperative mortality is observed in published records. Stroke, kidney failure and atrial fibrillation rates stay at 0.6, 0.4 and 12.9%, respectively. Analysis of beating heart TECAB procedures revealed a conversion rate of 15.3%, perioperative mortality 0.4%, stroke 0.3%, kidney failure 0.6% and atrial fibrillation 9.2%. Additionally, due to the obviously smaller surgical trauma, a remarkable fast return to normal daily activities can be demonstrated in clinical series of robotic assisted coronary bypass surgery. Short-term freedom of major adverse cardiac and cerebral events (MACCE) stays over 90%. Long-term studies reveal 5-year freedom of MACCE in the 75.2 to 83.1% range. Nowadays, total endoscopic coronary artery bypass grafting is a feasible and reproducible surgical method. Advanced hybrid coronary interventions offer complex multivessel TECAB with support of percutaneous coronary interventions (PCI). Combination of the above techniques widens the spectrum of minimally invasive therapeutic solutions concerning multivessel procedure including bilateral internal mammary grafts and drug-eluting stents.

Beware of the coronary arteries with implantable cardiac electronic devices.

The transvenous implantation of cardiac devices may sometimes cause serious complications involvingthe coronary arteries. The left anterior descending artery may be injured during nonapical right ventricular implantation while aright atrial lead may injure the right or circumflex coronary artery. Injury of aleft internal mammary graft to acoronary artery may cause myocardial infarction.

Invited Commentary

Invited Commentary

The impact of total arterial revascularization off pump coronary bypass grafting in impaired left ventricular function

BackgroundThe Arterial grafts have the advantage of durability and may have a protective effect by reducing the progression of native coronary artery disease (CAD) in grafted vessels. This study aimed to evaluate the impact of total arterial revascularization off pump coronary artery bypass grafting (CABG) in impaired left ventricular (LV) function patients with Ejection Fraction (EF) ≤ 35% concerning the short-term results. MethodsFrom August 2006 to August 2015, 287 patients with EF ≤ 35% out of 1950 patients underwent CABG in our Department of Cardiac-Thoracic Surgery, Zagazig University hospital, Egypt, for myocardial revascularization procedures were studied with a prospective registry of their data. Group 1 included 137 patients subjected to total arterial revascularization off Pump (TAROP) and Group 2 included 150 patients subjected to conventional technique (C-CABG). ResultsHospital mortality was less in group 1 (4.37% versus 4.66%). The duration of intensive care unit stay and the hospital stay were shorter in the group 1, with statistical significance. The mean graft patency rate for 113 (82.5%) patients of group 1 (TAROP) and 113 (75.3%) group 2 (C-CABG, utilizing internal mammary and venous grafts) at one month were 98.2% and 80.5% respectively. The short-term outcome revealed that the mean postoperative LVEF improved significantly, from 29% ± 1.7% to 41.0% ± 2.0% (p < 0.05) for group 1 with an improvement of the NYHA classification of the patients in both groups. ConclusionsTotal arterial revascularization off-pump CABG in impaired left ventricular function can be achieved in most cases with low complication and mortality rates and accepted results.

Trastuzumab uptake and its relation to efficacy in an animal model of HER2-positive breast cancer brain metastasis

PurposeThe extent to which efficacy of the HER2 antibody Trastuzumab in brain metastases is limited by access of antibody to brain lesions remains a question of significant clinical importance. We investigated the uptake and distribution of trastuzumab in brain and mammary fat pad grafts of HER2-positive breast cancer to evaluate the relationship of these parameters to the anti-tumor activity of trastuzumab and trastuzumab emtansine (T-DM1).MethodsMouse transgenic breast tumor cells expressing human HER2 (Fo2-1282 or Fo5) were used to establish intracranial and orthotopic tumors. Tumor uptake and tissue distribution of systemically administered 89Zr-trastuzumab or muMAb 4D5 (murine parent of trastuzumab) were measured by PET and ELISA. Efficacy of muMAb 4D5, the PI3K/mTOR inhibitor GNE-317, and T-DM1 was also assessed.Results89Zr-trastuzumab and muMAb 4D5 exhibited robust uptake into Fo2-1282 brain tumors, but not normal brains. Uptake into brain grafts was similar to mammary grafts. Despite this, muMAb 4D5 was less efficacious in brain grafts. Co-administration of muMAb 4D5 and GNE-317, a brain-penetrant PI3K/mTOR inhibitor, provided longer survival in mice with brain lesions than either agent alone. Moreover, T-DM1 increased survival in the Fo5 brain metastasis model.ConclusionsIn models of HER2-positive breast cancer brain metastasis, trastuzumab efficacy does not appear to be limited by access to intracranial tumors. Anti-tumor activity improved with the addition of a brain-penetrant PI3K/mTOR inhibitor, suggesting that combining targeted therapies is a more effective strategy for treating HER2-positive breast cancer brain metastases. Survival was also extended in mice with Fo5 brain lesions treated with T-DM1.