Transaortic septal myectomy at the time of aortic valve replacement for severe aortic stenosis: a case series of 55 cases.

Introduction: Symptomatic aortic valve stenosis (AS) is associated with asymmetric basal septal hypertrophy (ABSH) in 10% of cases. In this cohort, it has been suggested that rectification of the left ventricular outflow tract obstruction (LVOTO) by concomitant septal myectomy (CSM) can improve the results of aortic valve replacement (AVR). Objective: This study aims to present the technique of AVR with CSM for severe AS with ABSH and to determine the associated early and late post-operative outcomes. Methods: Fifty-five patients were prospectively recruited to undergo AVR with CSM between 2011 and 2021 at two centres. The primary outcomes were mortality within 30 days, incidence of post-operative ventricular septal defects (VSD) and prosthetic valve sizing. The secondary outcomes were in-hospital complications, permanent pacemaker implantation (PPI), survival at 15 months and changes on transthoracic echocardiogram. Results: Post-operative mortality was 1.8% and this figure was unchanged at 15-month follow-up. No patients developed a post-operative VSD. Intra-operatively, it was found that in 94.6% cases the direct valve sizing increased by one, when compared to the measurement made before CSM. The indexed effective orifice area (iEOA) was > 85 cm2/m2 in 96.4% and no patients had an iEOA ≤ 0.75 cm2/m2. Four patients (7.3%) required PPI due to complete atrioventricular block. Conclusion: AVR with CSM is a simple technique that can be utilised in severe AS with ABSH. There does not appear to be an increase in mortality or incidence of iatrogenic VSDs. Importantly, CSM allows for the implantation of a larger aortic valve compared to measurements made before CSM.

Prophylactic corticosteroids for cardiopulmonary bypass in adult cardiac surgery.

BACKGROUND: Cardiac surgery triggers a strong inflammatory reaction, which carries significant clinical consequences. Corticosteroids have been suggested as a potential perioperative strategy to reduce inflammation and help prevent postoperative complications. However, the safety and effectiveness of perioperative corticosteroid use in adult cardiac surgery is uncertain. This is an update of the 2011 review with 18 studies added. OBJECTIVES: Primary objective: to estimate the effects of prophylactic corticosteroid use in adults undergoing cardiac surgery with cardiopulmonary bypass on the: - co-primary endpoints of mortality, myocardial complications, and pulmonary complications; and - secondary outcomes including atrial fibrillation, infection, organ injury, known complications of steroid therapy, prolonged mechanical ventilation, prolonged postoperative stay, and cost-effectiveness. SECONDARY OBJECTIVE: to explore the role of characteristics of the study cohort and specific features of the intervention in determining the treatment effects via a series of prespecified subgroup analyses. SEARCH METHODS: We used standard, extensive Cochrane search methods to identify randomised studies assessing the effect of corticosteroids in adult cardiac surgery. The latest searches were performed on 14 October 2022. SELECTION CRITERIA: We included randomised controlled trials in adults (over 18 years, either with a diagnosis of coronary artery disease or cardiac valve disease, or who were candidates for cardiac surgery with the use of cardiopulmonary bypass), comparing corticosteroids with no treatments. There were no restrictions with respect to length of the follow-up period. All selected studies qualified for pooling of results for one or more endpoints. DATA COLLECTION AND ANALYSIS: We used standard Cochrane methods. Our primary outcomes were all-cause mortality, and cardiac and pulmonary complications. Secondary outcomes were infectious complications, gastrointestinal bleeding, occurrence of new post-surgery atrial fibrillation, re-thoracotomy for bleeding, neurological complications, renal failure, inotropic support, postoperative bleeding, mechanical ventilation time, length of stays in the intensive care unit (ICU) and hospital, patient quality of life, and cost-effectiveness. We used GRADE to assess the certainty of evidence for each outcome. MAIN RESULTS: This updated review includes 72 randomised trials with 17,282 participants (all 72 trials with 16,962 participants were included in data synthesis). Four trials (6%) were considered at low risk of bias in all the domains. The median age of participants included in the studies was 62.9 years. Study populations consisted mainly (89%) of low-risk, first-time coronary artery bypass grafting (CABG) or valve surgery. The use of perioperative corticosteroids may result in little to no difference in all-cause mortality (risk with corticosteroids: 25 to 36 per 1000 versus 33 per 1000 with placebo or no treatment; risk ratio (RR) 0.90, 95% confidence interval (CI) 0.75 to 1.07; 25 studies, 14,940 participants; low-certainty evidence). Corticosteroids may increase the risk of myocardial complications (68 to 86 per 1000) compared with placebo or no treatment (66 per 1000; RR 1.16, 95% CI 1.04 to 1.31; 25 studies, 14,766 participants; low-certainty evidence), and may reduce the risk of pulmonary complications (risk with corticosteroids: 61 to 77 per 1000 versus 78 per 1000 with placebo/no treatment; RR 0.88, 0.78 to 0.99; 18 studies, 13,549 participants; low-certainty evidence). Analyses of secondary endpoints showed that corticosteroids may reduce the incidence of infectious complications (risk with corticosteroids: 94 to 113 per 1000 versus 123 per 1000 with placebo/no treatment; RR 0.84, 95% CI 0.76 to 0.92; 28 studies, 14,771 participants; low-certainty evidence). Corticosteroids may result in little to no difference in incidence of gastrointestinal bleeding (risk with corticosteroids: 9 to 17 per 1000 versus 10 per 1000 with placebo/no treatment; RR 1.21, 95% CI 0.87 to 1.67; 6 studies, 12,533 participants; low-certainty evidence) and renal failure (risk with corticosteroids: 23 to 35 per 1000 versus 34 per 1000 with placebo/no treatment; RR 0.84, 95% CI 0.69 to 1.02; 13 studies, 12,799; low-certainty evidence). Corticosteroids may reduce the length of hospital stay, but the evidence is very uncertain (-0.5 days, 0.97 to 0.04 fewer days of length of hospital stay compared with placebo/no treatment; 25 studies, 1841 participants; very low-certainty evidence). The results from the two largest trials included in the review possibly skew the overall findings from the meta-analysis. AUTHORS' CONCLUSIONS: A systematic review of trials evaluating the organ protective effects of corticosteroids in cardiac surgery demonstrated little or no treatment effect on mortality, gastrointestinal bleeding, and renal failure. There were opposing treatment effects on cardiac and pulmonary complications, with evidence that corticosteroids may increase cardiac complications but reduce pulmonary complications; however, the level of certainty for these estimates was low. There were minor benefits from corticosteroid therapy for infectious complications, but the evidence on hospital length of stay was very uncertain. The inconsistent treatment effects across different outcomes and the limited data on high-risk groups reduced the applicability of the findings. Further research should explore the role of these drugs in specific, vulnerable cohorts.

Effect of on-pump vs. off-pump coronary artery bypass grafting in patients with non-dialysis-dependent severe renal impairment: propensity-matched analysis from the UK registry dataset.

Introduction: On-pump coronary artery bypass (ONCABG) grafting in patients with a pre-existing poor renal reserve is known to carry significant morbidity and mortality. There is limited controversial evidence on the benefit of off-pump coronary artery bypass (OPCABG) grafting in these high-risk groups of patients. We compared early clinical outcomes in propensity-matched cohorts of patients with non-dialysis-dependent pre-operative severe renal impairment undergoing OPCABG vs. ONCABG, captured in a large national registry dataset. Methods: All data for patients with a pre-operative creatinine clearance of less than 50 mL/min who underwent elective or urgent isolated OPCABG or ONCABG from 1996 to 2019 were extracted from the UK National Adult Cardiac Surgery Audit (NACSA) database. Propensity score matching was performed using 1:1 nearest neighbor matching without replacement using several baseline characteristics. We investigated the effect of ONCABG vs. OPCABG in the matched cohort using cluster-robust standard error regression. Results: We identified 8,628 patients with severe renal impairment undergoing isolated CABG, of whom 1,142 (13.23%) underwent OPCABG during the study period. We compared 1,141 propensity-matched pairs of patients undergoing OPCABG vs. ONCABG. The median age of the matched population was 78 years in both groups, with no significant imbalance post-matching in the rest of the variables. There was no difference between OPCABG and ONCABG in in-hospital mortality rates, post-operative dialysis, and stroke rates. However, the return to theatre for bleeding or tamponade was higher in ONCABG vs. OPCABG (P > 0.02); however, OPCABG reduced the total length of stay in the hospital by 1 day (P = 0.008). After double adjustment in the matched population using cluster-robust standard regression, ONCABG did not increase mortality compared to OPCABG (OR, 1.05, P = 0.78), postoperative stroke (OR, 1.7, P = 0.12), and dialysis (OR, 0.7, P = 0.09); however, ONCABG was associated with an increased risk of bleeding (OR, 1.53, P = 0.03). Discussion: In this propensity analysis of a large national registry dataset, we found no difference in early mortality and stroke in patients with pre-operative severe renal impairment undergoing OPCABG or ONCABG surgery; however, ONCABG was associated with an increased risk of return to theatre for bleeding and an increased length of hospital stay.

Osteopontin Activation and Microcalcification in Venous Grafts Can Be Modulated by Dexamethasone.

BACKGROUND: Osteopontin has been implicated in vascular calcification formation and vein graft intimal hyperplasia, and its expression can be triggered by pro-inflammatory activation of cells. The role of osteopontin and the temporal formation of microcalcification in vein grafts is poorly understood with a lack of understanding of the interaction between haemodynamic changes and the activation of osteopontin. METHODS: We used a porcine model of vein interposition grafts, and human long saphenous veins exposed to ex vivo perfusion, to study the activation of osteopontin using polymerase chain reaction, immunostaining, and 18F-sodium fluoride autoradiography. RESULTS: The porcine model showed that osteopontin is active in grafts within 1 week following surgery and demonstrated the presence of microcalcification. A brief pretreatment of long saphenous veins with dexamethasone can suppress osteopontin activation. Prolonged culture of veins after exposure to acute arterial haemodynamics resulted in the formation of microcalcification but this was suppressed by pretreatment with dexamethasone. 18F-sodium fluoride uptake was significantly increased as early as 1 week in both models, and the pretreatment of long saphenous veins with dexamethasone was able to abolish its uptake. CONCLUSIONS: Osteopontin is activated in vein grafts and is associated with microcalcification formation. A brief pretreatment of veins ex vivo with dexamethasone can suppress its activation and associated microcalcification.

Trends and outcomes of concomitant aortic valve replacement and coronary artery bypass grafting in the UK and a survey of practices.

OBJECTIVES: Concomitant revascularization of coronary artery disease at the same time as treatment for aortic valvopathy favourably impacts survival. However, combined surgery may be associated with increased adverse outcomes compared to aortic valve replacement (AVR) or coronary artery bypass grafting in isolation. METHODS: We retrospectively analyzed all patients who underwent AVR with bypass grafting between February 1996 and March 2019 using data from the National Adult Cardiac Surgery Audit. We used a generalized mixed-effects model to assess the effect of the number and type of bypass grafts associated with surgical AVR on in-hospital mortality, postoperative stroke, and the need for renal dialysis. Furthermore, we conducted an international cross-sectional survey of cardiac surgeons to explore their views about concomitant AVR with coronary bypass grafting interventions. RESULTS: Fifty-one thousand two hundred and seventy-two patients were included in the study. Patients receiving 2 or more bypass grafts demonstrated more significant preoperative comorbidity and disease severity. Patients undergoing 2 and >2 grafts in addition to AVR had increased mortality as compared to patients undergoing AVR and only 1 graft [odds ratio (OR) 1.17, 95% confidence interval (CI) [1.05-1.30], P = 0.005 and OR 1.15, 95% CI [1.02-1.30], P = 0.024 respectively]. A single arterial conduit was associated with a reduction in mortality (OR 0.75, 95% CI [0.68-0.82], P < 0.001) and postoperative dialysis (OR 0.87, 95% CI [0.78-0.96], P = 0.006), but this association was lost with >1 arterial conduit. One hundred and three surgeons responded to our survey, with only a small majority believing that the number of bypass grafts can influence short- or long-term postoperative outcomes in these patients, and an almost equal split in responders supporting the use of staged or hybrid interventions for patients with concomitant pathology. CONCLUSIONS: The number of grafts performed during combined AVR and coronary artery bypass grafting is associated with increased morbidity and mortality. The use of an arterial graft was also associated with reduced mortality. Future studies are needed to assess the effect of incomplete revascularization and measure long-term outcomes. Based on our data, current published evidence, and the collective expert opinion we gathered, we endorse future work to investigate the short and long-term efficacy and safety of hybrid intervention for patients with concomitant advanced coronary and aortic valve disease.

The Role of Preservation Solutions upon Saphenous Vein Endothelial Integrity and Function: Systematic Review and UK Practice Survey.

The long saphenous vein is the most used conduit in cardiac surgery, but its long-term patency is limited by vein graft disease (VGD). Endothelial dysfunction is a key driver of VGD; its aetiology is multi-factorial. However emerging evidence identifies vein conduit harvest technique and preservation fluids as causal in their onset and propagation. This study aims to comprehensively review published data on the relationship between preservation solutions, endothelial cell integrity and function, and VGD in human saphenous veins harvested for CABG. The review was registered with PROSPERO (CRD42022358828). Electronic searches of Cochrane Central Register of Controlled Trials, MEDLINE, and EMBASE databases were undertaken from inception until August 2022. Papers were evaluated in line with registered inclusion and exclusion criteria. Searches identified 13 prospective, controlled studies for inclusion in the analysis. All studies used saline as a control solution. Intervention solutions included heparinised whole blood and saline, DuraGraft, TiProtec, EuroCollins, University of Wisconsin (UoW), buffered, cardioplegic and Pyruvate solutions. Most studies demonstrated that normal saline appears to have negative effects on venous endothelium and the most effective preservation solutions identified in this review were TiProtec and DuraGraft. The most used preservation solutions in the UK are heparinised saline or autologous whole blood. There is substantial heterogeneity both in practice and reporting of trials evaluating vein graft preservation solutions, and the quality of existing evidence is low. There is an unmet need for high quality trials evaluating the potential for these interventions to improve long-term patency in venous bypass grafts.

Large animal model of vein grafts intimal hyperplasia: A systematic review.

Coronary artery bypass grafting remains the treatment of choice for a large cohort of patients with significant coronary disease. Despite the increased use of arterial grafts, the long saphenous vein remains the most commonly used conduit. Long-term graft patency continues to be the Achilles heel of saphenous vein grafts. This is due to the development of intimal hyperplasia, a chronic inflammatory disease that results in the narrowing and occlusion of a significant number of vein grafts. Research models for intimal hyperplasia are essential for a better understanding of pathophysiological processes of this condition. Large animal models resemble human anatomical structures and have been used as a surrogate to study disease development and prevention over the years. In this paper, we systematically review all published studies that utilized large animal models of vein graft disease with a focus on the type of model and any therapeutic intervention, specifically the use of external stents/mesh.

The Role of Endothelial Cells in the Onset, Development and Modulation of Vein Graft Disease.

Endothelial cells comprise the intimal layer of the vasculature, playing a crucial role in facilitating and regulating aspects such nutrient transport, vascular homeostasis, and inflammatory response. Given the importance of these cells in maintaining a healthy haemodynamic environment, dysfunction of the endothelium is central to a host of vascular diseases and is a key predictor of cardiovascular risk. Of note, endothelial dysfunction is believed to be a key driver for vein graft disease-a pathology in which vein grafts utilised in coronary artery bypass graft surgery develop intimal hyperplasia and accelerated atherosclerosis, resulting in poor long-term patency rates. Activation and denudation of the endothelium following surgical trauma and implantation of the graft encourage a host of immune, inflammatory, and cellular differentiation responses that risk driving the graft to failure. This review aims to provide an overview of the current working knowledge regarding the role of endothelial cells in the onset, development, and modulation of vein graft disease, as well as addressing current surgical and medical management approaches which aim to beneficially modulate endothelial function and improve patient outcomes.

Evaluating the Feasibility of Screening Relatives of Patients Affected by Nonsyndromic Thoracic Aortic Diseases: The REST Study.

Background Diseases of the thoracic aorta are characterized by a familial etiology in up to 30% of the cases. Nonsyndromic thoracic aorta diseases (NS-TADs) lack overt clinical signs and systemic features, which hinder early detection and prompt surgical intervention. We hypothesize that tailored genetic testing and imaging of first-degree and second-degree relatives of patients affected by NS-TADs may enable early diagnosis and allow appropriate surveillance or intervention. Methods and Results We conducted a feasibility study involving probands affected by familial or sporadic NS-TADs who had undergone surgery, which also offered screening to their relatives. Each participant underwent a combined imaging (echocardiogram and magnetic resonance imaging) and genetic (whole exome sequencing) evaluation, together with physical examination and psychological assessment. The study population included 16 probands (8 sporadic, 8 familial) and 54 relatives (41 first-degree and 13 second-degree relatives) with median age 48 years (range: 18-85 years). No syndromic physical features were observed. Imaging revealed mild-to-moderate aortic dilation in 24% of relatives. A genetic variant of uncertain significance was identified in 3 families. Imaging, further phenotyping, or a form of secondary prevention was indicated in 68% of the relatives in the familial group and 54% in the sporadic group. No participants fulfilled criteria for aortic surgery. No differences between baseline and 3-month follow-up scores for depression, anxiety, and self-reported quality of life were observed. Conclusions In NS-TADs, imaging tests, genetic counseling, and family screening yielded positive results in up to 1 out of 4 screened relatives, including those in the sporadic NS-TAD group. Registration URL: https://www.clinicaltrials.gov; Unique identifier: NCT03861741.

Acute shear stress and vein graft disease.

The long saphenous vein is commonly used in cardiac surgery to bypass occluded coronary arteries. Its use is complicated by late stenosis and occlusion due to the development of intimal hyperplasia. It is accepted that intimal hyperplasia is a multifactorial inflammatory process that starts immediately after surgery. The role of acute changes in haemodynamic conditions when the vein is implanted into arterial circulation, especially shear stress, is not fully appreciated. This review provides an overview of intimal hyperplasia and the effect of acute shear stress changes on the activation of pro-inflammatory mediators.

Gene and metabolite expression dependence on body mass index in human myocardium.

We hypothesized that body mass index (BMI) dependent changes in myocardial gene expression and energy-related metabolites underlie the biphasic association between BMI and mortality (the obesity paradox) in cardiac surgery. We performed transcriptome profiling and measured a panel of 144 metabolites in 53 and 55, respectively, myocardial biopsies from a cohort of sixty-six adult patients undergoing coronary artery bypass grafting (registration: NCT02908009). The initial analysis identified 239 transcripts with biphasic BMI dependence. 120 displayed u-shape and 119 n-shape expression patterns. The identified local minima or maxima peaked at BMI 28-29. Based on these results and to best fit the WHO classification, we grouped the patients into three groups: BMI < 25, 25 ≤ BMI ≤ 32, and BMI > 32. The analysis indicated that protein translation-related pathways were downregulated in 25 ≤ BMI ≤ 32 compared with BMI < 25 patients. Muscle contraction transcripts were upregulated in 25 ≤ BMI ≤ 32 patients, and cholesterol synthesis and innate immunity transcripts were upregulated in the BMI > 32 group. Transcripts involved in translation, muscle contraction and lipid metabolism also formed distinct correlation networks with biphasic dependence on BMI. Metabolite analysis identified acylcarnitines and ribose-5-phosphate increasing in the BMI > 32 group and α-ketoglutarate increasing in the BMI < 25 group. Molecular differences in the myocardium mirror the biphasic relationship between BMI and mortality.

The impact of patient-prosthesis mismatch on early and long-term survival after aortic replacement with the Edwards Perimount valve: A propensity score-matched analysis.

BACKGROUND: To investigate the impact of severe patient-prosthesis mismatch (PPM) related to the Edwards Lifesciences Perimount (EP) bioprosthesis in the aortic position on early in-hospital outcomes and long-term survival. METHODS: A total of 5964 consecutive patients underwent aortic valve replacement at the Bristol Heart Institute between 1998 and 2014, 2667 representing the cohort of this study received EP. PPM was defined severe as EOAi < 0.65 cm2 /m2 . To minimize bias, propensity score matching was conducted and two groups A and B (without and with severe PPM) of 320 patients with similar preoperative characteristics were matched. We assessed early in-hospital outcomes including CVA, re-exploration for bleeding, low cardiac output, wound infection, acute renal injury, length of hospital stay, and long-term survival for both groups in unmatched and matched populations. RESULTS: In the unmatched analysis, 18.3% of patients had severe PPM. Severe PPM was not associated with increased in-hospital mortality (4.5% vs. 2.9%, respectively, p = .09) or any other early adverse outcomes except increased length of hospital stay (10.57 ± 8.2 vs. 11.7 ± 9.4, respectively, p = .01). Long-term survival differed significantly between groups at 2 and 8 years (91.8% vs. 91.4% and 60.5% vs. 55.7%, respectively, p = .02). Matched analysis showed no differences between the groups in early health outcomes and overall survival at 2 and 8 years was also similar (89.7% vs. 91% and 57.3% vs. 58%, group A vs. B, respectively p = .9). CONCLUSION: Presence of PPM does not seem to affect early in-hospital outcomes or late survival when using EP in patients undergoing aortic valve replacement.

Benefits of mitral valve repair over replacement in the elderly: a systematic review and meta-analysis.

OBJECTIVES: Mitral valve (MV) repair has demonstrated excellent short- and long-term outcomes, however, its merit in the elderly population is still debated. We conducted a meta-analysis of studies that have compared the MV repair to replacement in the elderly population. METHODS: A systematic literature search was conducted for any study published on MV surgery on elderly patients (≥75 years old). A pooled risk-ratio meta-analysis was done to evaluate short-term mortality, postoperative complications, surgical timings, and long-term survival rates. RESULTS: A total of nine retrospective observational studies were included in the quantitative meta-analysis. Pooled meta-analysis showed a reduced risk of short-term mortality for the MV repair group (risk ratio [RR] = 0.41 [0.24-0.71], p-value = .005). Postoperative neurological complications were in favor of repair, although not significantly (RR = 0.49 [0.21-1.11], p-value = .07). Operative timings (cardiopulmonary bypass and crossclamp time) were not different between the groups although no data were available on the complexity of the repairs. Long-term survival rates were in favor of the repairs (pooled treatment effect of -0.47 [-0.64; -0.29], p = .005). CONCLUSIONS: MV surgery is a safe and effective procedure for the elderly. MV repair demonstrated better short-term outcomes compared to replacement. Long-term survival rates are significantly better after repair.

Combination of internal (epicardial) and external (transthoracic) defibrillation during heart surgery.

OBJECTIVES: This report describes a modified defibrillation technique during cardiac surgery using a combined internal (epicardial) and external (transthoracic) defibrillation system. METHODS: We routinely used 30 J (J) shock between the epicardial pad placed directly onto the right atrium and the left anterolateral transthoracic pad placed in the left anterolateral chest wall directly to the skin in the area of the cardiac apex under the nipple. RESULTS: Thirty-two patients whom developed ventricular fibrillation (VF) during surgery were managed in theatre using this method. A single 30 J shock was successfully given in 29 patients while the remaining three required an additional shock with the same amount (30 J). CONCLUSIONS: We believe that this technique is safe and complications free. It is easy to perform especially in patients with difficult access such as redo operations.

NF-κB inhibition prevents acute shear stress-induced inflammation in the saphenous vein graft endothelium.

The long saphenous vein (LSV) is commonly used as a conduit in coronary artery bypass grafting. However, long term patency remains limited by the development of vascular inflammation, intimal hyperplasia and accelerated atherosclerosis. The impact of acute exposure of venous endothelial cells (ECs) to acute arterial wall shear stress (WSS) in the arterial circulation, and the subsequent activation of inflammatory pathways, remain poorly defined. Here, we tested the hypothesis that acute exposure of venous ECs to high shear stress is associated with inflammatory responses that are regulated by NF-κB both in-vitro and ex-vivo. Analysis of the LSV endothelium revealed that activation of NF-κB occurred within 30 min after exposure to arterial rates of shear stress. Activation of NF-κB was associated with increased levels of CCL2 production and enhanced binding of monocytes in LSVECs exposed to 6 h acute arterial WSS. Consistent with this, ex vivo exposure of LSVs to acute arterial WSS promoted monocyte interactions with the vessel lumen. Inhibition of the NF-κB pathway prevented acute arterial WSS-induced CCL2 production and reduced monocyte adhesion, both in vitro and in human LSV ex vivo, demonstrating that this pathway is necessary for the induction of the acute arterial WSS-induced pro-inflammatory response. We have identified NF-κB as a critical regulator of acute endothelial inflammation in saphenous vein in response to acute arterial WSS. Localised endothelial-specific inhibition of the NF-κB pathway may be beneficial to prevent vein graft inflammation and consequent failure.

Saphenous vein graft disease, pathophysiology, prevention, and treatment. A review of the literature.

BACKGROUND: The saphenous vein remains the most frequently used conduit for coronary artery bypass grafting, despite reported unsatisfactory long-term patency rates. Understanding the pathophysiology of vein graft failure and attempting to improve its longevity has been a significant area of research for more than three decades. This article aims to review the current understanding of the pathophysiology and potential new intervention strategies. METHODS: A search of three databases: MEDLINE, Web of Science, and Cochrane Library, was undertaken for the terms "pathophysiology," "prevention," and "treatment" plus the term "vein graft failure." RESULTS: Saphenous graft failure is commonly the consequence of four different pathophysiological mechanisms, early acute thrombosis, vascular inflammation, intimal hyperplasia, and late accelerated atherosclerosis. Different methods have been proposed to inhibit or attenuate these pathological processes including modified surgical technique, topical pretreatment, external graft support, and postoperative pharmacological interventions. Once graft failure occurs, the available treatments are either surgical reintervention, angioplasty, or conservative medical management reserved for patients not eligible for either procedure. CONCLUSION: Despite the extensive amount of research performed, the pathophysiology of saphenous vein graft is still not completely understood. Surgical and pharmacological interventions have improved early patency and different strategies for prevention seem to offer some hope in improving long-term patency.

Combined Degenerative Mitral Valve and Coronary Surgery: Early Outcomes and 10-Year Survival.

BACKGROUND: This study investigated the impact of combined degenerative mitral valve (DMV) and coronary artery bypass grafting (CABG+DMV) surgery vs DMV surgery only on in-hospital health outcome and 10-year survival. METHODS: We identified 745 patients with DMV disease. Of these, 186 (24.9%) were affected also by coronary disease and underwent combined DMV+CABG. They were compared with the remaining 559 patients receiving DMV-only surgery in in-hospital and 1-, 5-, and 10-year survival. We evaluated a short-term composite outcome of hospital mortality, acute kidney injury, cerebrovascular events, and low cardiac output requiring postoperative use of intraaortic balloon pump. In addition, we assessed mitral valve repair rates over time and their correlation with long-term survival. To minimize bias, we conducted a propensity score-matching analysis. RESULTS: DMV+CABG surgery was associated with a similar incidence of the composite end point compared with DMV-only surgery in the unmatched analysis (6.5% vs 5.4%, P = .71) and matched analysis (7.5% vs 8.2%, P = .82). The 10-year survival was 70.5% vs 68.6% (P = .07) for the unmatched analysis and 64.6% vs 62.5% (P = .9) for the matched analysis, DMV+CABG vs DMV-only, respectively. Mitral valve repair had a beneficial effect on short-term outcomes and long-term mortality rates, regardless the presence of concomitant coronary surgery. CONCLUSIONS: Combined DMV+CABG surgery is a very effective surgical treatment with high mitral valve repair rate. Early in-hospital outcome and long-term survival are comparable with DMV-only surgery. In these combined procedures, mitral valve repair is associated with better long-term survival.