Lack of efficacy of aprotinin over tranexamic acid in type A aortic dissection repair.

BACKGROUND: The role of aprotinin in modern cardiac surgery is not well defined. While licensed for use in isolated coronary artery bypass grafting it is more commonly used for cases deemed to be at an increased risk of bleeding. The relative efficacy, and safety profile, of aprotinin as compared to other antifibrinolytics in these high-risk cases is uncertain. STUDY DESIGN AND METHODS: A retrospective observational study with propensity matching to determine whether aprotinin versus tranexamic acid reduced bleeding or transfusion requirements in patients presenting for surgical repair of type A aortic dissection (TAD). RESULTS: Between 2016 and 2022, 250 patients presented for repair of TAD. A total of 231 patients were included in the final analysis. Bleeding and transfusion were similar between both groups in both propensity matched and unmatched cohorts. Compared to tranexamic acid, aprotinin use did not reduce transfusion requirements for any product. Rates of bleeding in the first 12 h, return to theater and return to intensive care unit with an open packed chest were similar between groups. There was no difference in rates of renal failure, stroke, or death. CONCLUSION: Aprotinin did not reduce the risk of bleeding or transfusion requirements in patients undergoing repair of type A aortic dissections. Efficacy of aprotinin may vary depending on the type of surgery performed and the underlying pathology.

Hybrid noncovered open stents in repair of DeBakey type 1 acute aortic dissections.

OBJECTIVES: The indications for use, evidence base and experience with the novel noncovered open hybrid surgical stents for acute type A aortic dissection repair for concurrent stabilization of the 'downstream' aorta remains limited. We review the evidence base and the development of these stents. METHODS: Data were collected from Pubmed/Medline literature search to develop and review the evidence base for safety and efficacy of non-covered surgical stents. Existing guidelines for use and developments were reviewed. RESULTS: A single randomized control trial and 4 single-centre studies were included in the review with a total worldwide experience of 241 patients. The deployment was easy and did not add significantly to the primary operation. The mortality and new stroke ranged from 6.3-18.7%. Safe and complete deployment was accomplished in 92-100%. There was no device-related reintervention. There was a significant improvement in malperfusion in over 90% of the cases with varying degrees of remodelling (60-90%) of the downstream aorta. CONCLUSIONS: Open noncovered stent grafts represent a major technical advancement as an adjunct procedure for acute dissection repairs, e.g. hemiarch repair. It has potential for wider use by non-aortic surgeons due to simplicity of technique. Limited safety and efficacy data confirm the device to be safe, feasible and reproducible with potential for wider adoption. However, long-term trial and registry data are required before recommendations for standard use outside of high-volume experienced aortic centres.

Management of anomalous origin of right coronary artery from left coronary sinus.

Aberrant origin of coronary artery is a rare congenital anomaly associated with increased risk of myocardial ischemia and sudden death, with the highest risk lesions being those arising from the opposite sinus of Valsalva. We report a case with an aberrant right coronary artery arising superior to the left coronary cusp, with a slit-like ostium, having an inter-arterial and intramural course through the aortic root, that underwent repositioning of the right coronary artery. We believe such cases warrant surgical correction and reimplantation is a safe, effective and reproducible technique.

Perioperative neuromonitoring during thoracoabdominal aortic aneurysm open repair: a systematic review.

OBJECTIVES: While open surgical repair remains the gold standard for thoracoabdominal aortic aneurysm (TAAA) treatment, there is still no consensus regarding perioperative neuromonitoring technique for prevention of spinal cord ischaemia. METHODS: In this systematic review, we aimed to explore the effects and practices of neuromonitoring during the open TAAA repair. A systematic literature search in PubMed, Embase via Ovid, Cochrane library and ClinicalTrialsGov until December 2022 was performed. RESULTS: A total of 535 studies were identified from the literature search, of which 27 studies including a total of 3130 patients met the eligibility criteria. Most studies (21 out of 27, 78%) investigated the feasibility of motor-evoked potentials (MEP), while 15 analysed somatosensory-evoked potentials (SSEP) and 2 studies analysed near-infrared spectroscopy during open TAAA repair. CONCLUSIONS: Current literature suggest that rates of postoperative spinal cord ischaemia can be kept at low levels after open TAAA repair with the adequate precautions and perioperative manoeuvres. Neuromonitoring with MEP provides the surgeon objective criteria to direct selective intercostal reconstruction or other protective anaesthetic and surgical manoeuvres. Simultaneous monitoring of MEP and SSEP is a reliable method that can rapidly detect important findings and direct adequate protective manoeuvres during open TAAA repair.

Effects of the harvesting technique and external stenting on progression of vein graft disease 2 years after coronary artery bypass.

OBJECTIVES: In a post hoc analysis of the VEST III trial, we investigated the effect of the harvesting technique on saphenous vein graft (SVG) patency and disease progression after coronary artery bypass grafting. METHODS: Angiographic outcomes were assessed in 183 patients undergoing open (126 patients, 252 SVG) or endoscopic harvesting (57 patients, 114 SVG). Overall SVG patency was assessed by computed tomography angiography at 6 months and by coronary angiography at 2 years. Fitzgibbon patency (FP I, II and III) and intimal hyperplasia (IH) in a patient subset were assessed by coronary angiography and intravascular ultrasound, respectively, at 2 years. RESULTS: Baseline characteristics were similar between patients who underwent open and those who underwent endoscopic harvesting. Open compared with endoscopic harvesting was associated with higher overall SVG patency rates at 6 months (92.9% vs 80.4%, P = 0.04) and 2 years (90.8% vs 73.9%, P = 0.01), improved FP I, II and III rates (65.2% vs 49.2%; 25.3% vs 45.9%, and 9.5% vs 4.9%, respectively; odds ratio 2.81, P = 0.09) and reduced IH area (-31.8%; P = 0.04) and thickness (-28.9%; P = 0.04). External stenting was associated with improved FP I, II and III rates (odds ratio 2.84, P = 0.01), reduced IH area (-19.5%; P < 0.001) and thickness (-25.0%; P < 0.001) in the open-harvest group and reduced IH area (-12.7%; P = 0.01) and thickness (-9.5%; P = 0.21) in the endoscopic-harvest group. CONCLUSIONS: A post-hoc analysis of the VEST III trial showed that open harvesting is associated with improved overall SVG patency and reduced IH. External stenting reduces SVG disease progression, particularly with open harvesting.

Corrigendum to: A rare cause of culture negative bioprosthetic valve endocarditis: a case report of Aggregatibacter aphrophilus infection.

[This corrects the article DOI: 10.1093/ehjcr/ytab003.].

Epilepsy related multimorbidity, polypharmacy and risks in adults with intellectual disabilities: a national study.

BACKGROUND: A quarter of people with Intellectual Disability (ID) in the UK have epilepsy compared to 0.6% in the general population and die much younger. Epilepsy is associated with two-fifths of all deaths with related polypharmacy and multi-morbidity. Epilepsy research on this population has been poor. This study describes real-world clinical and risk characteristics of a large cohort across England and Wales. METHODS: A retrospective multi-centre cohort study was conducted. Information on seizure characteristics, ID severity, relevant co-morbidities, psychotropic and antiseizure drugs (ASDs), SUDEP and other risk factors was collected across a year. RESULTS: Of 904 adults across 10 centres (male:female, 1.5:1), 320 (35%) had mild ID and 584 (65%) moderate-profound (M/P) ID. The mean age was 39.9 years (SD 15.0). Seizures were more frequent in M/P ID (p < 0.001). Over 50% had physical health co-morbidities, more in mild ID (p < 0.01). A third had psychiatric co-morbidity and a fifth had an underlying genetic disorder. Autism Spectrum Disorder was seen in over a third (37%). Participants were on median two ASDs and overall, five medications. Over quarter were on anti-psychotics. Over 90% had an epilepsy review in the past year but 25% did not have an epilepsy care plan, particularly those with mild ID (p < 0.001). Only 61% had a documented discussion of SUDEP, again less likely with mild ID or their care stakeholders (p < 0.001). CONCLUSIONS: Significant levels of multi-morbidity, polypharmacy and a lack of systemised approach to treatment and risk exist. Addressing these concerns is essential to reduce premature mortality.

External stenting and disease progression in saphenous vein grafts two years after coronary artery bypass grafting: A multicenter randomized trial.

OBJECTIVES: Little data exist regarding the potential of external stents to mitigate long-term disease progression in saphenous vein grafts. We investigated the effect of external stents on the progression of saphenous vein graft disease. METHODS: A total of 184 patients undergoing isolated coronary artery bypass grafting, using an internal thoracic artery graft and at least 2 additional saphenous vein grafts, were enrolled in 14 European centers. One saphenous vein graft was randomized to an external stent, and 1 nonstented saphenous vein graft served as the control. The primary end point was the saphenous vein graft Fitzgibbon patency scale assessed by angiography, and the secondary end point was saphenous vein graft intimal hyperplasia assessed by intravascular ultrasound in a prespecified subgroup at 2 years. RESULTS: Angiography was completed in 128 patients and intravascular ultrasound in the entire prespecified cohort (n = 51) at 2 years. Overall patency rates were similar between stented and nonstented saphenous vein grafts (78.3% vs 82.2%, P = .43). However, the Fitzgibbon patency scale was significantly improved in stented versus nonstented saphenous vein grafts, with Fitzgibbon patency scale I, II, and III rates of 66.7% versus 54.9%, 27.8% versus 34.3%, and 5.5% versus 10.8%, respectively (odds ratio, 2.02; P = .03). Fitzgibbon patency scale was inversely related to saphenous vein graft minimal lumen diameter, with Fitzgibbon patency scale I, II, and III saphenous vein grafts having an average minimal lumen diameter of 2.62 mm, 1.98 mm, and 1.32 mm, respectively (P < .05). Externally stented saphenous vein grafts also showed significant reductions in mean intimal hyperplasia area (22.5%; P < .001) and thickness (23.5%; P < .001). CONCLUSIONS: Two years after coronary artery bypass grafting, external stenting improves Fitzgibbon patency scales of saphenous vein grafts and significantly reduces intimal hyperplasia area and thickness. Whether this will eventually lead to improved long-term patency is still unknown.

Optimal protamine dosing after cardiopulmonary bypass: The PRODOSE adaptive randomised controlled trial.

BACKGROUND: The dose of protamine required following cardiopulmonary bypass (CPB) is often determined by the dose of heparin required pre-CPB, expressed as a fixed ratio. Dosing based on mathematical models of heparin clearance is postulated to improve protamine dosing precision and coagulation. We hypothesised that protamine dosing based on a 2-compartment model would improve thromboelastography (TEG) parameters and reduce the dose of protamine administered, relative to a fixed ratio. METHODS AND FINDINGS: We undertook a 2-stage, adaptive randomised controlled trial, allocating 228 participants to receive protamine dosed according to a mathematical model of heparin clearance or a fixed ratio of 1 mg of protamine for every 100 IU of heparin required to establish anticoagulation pre-CPB. A planned, blinded interim analysis was undertaken after the recruitment of 50% of the study cohort. Following this, the randomisation ratio was adapted from 1:1 to 1:1.33 to increase recruitment to the superior arm while maintaining study power. At the conclusion of trial recruitment, we had randomised 121 patients to the intervention arm and 107 patients to the control arm. The primary endpoint was kaolin TEG r-time measured 3 minutes after protamine administration at the end of CPB. Secondary endpoints included ratio of kaolin TEG r-time pre-CPB to the same metric following protamine administration, requirement for allogeneic red cell transfusion, intercostal catheter drainage at 4 hours postoperatively, and the requirement for reoperation due to bleeding. The trial was listed on a clinical trial registry (ClinicalTrials.gov Identifier: NCT03532594). Participants were recruited between April 2018 and August 2019. Those in the intervention/model group had a shorter mean kaolin r-time (6.58 [SD 2.50] vs. 8.08 [SD 3.98] minutes; p = 0.0016) post-CPB. The post-protamine thromboelastogram of the model group was closer to pre-CPB parameters (median pre-CPB to post-protamine kaolin r-time ratio 0.96 [IQR 0.78-1.14] vs. 0.75 [IQR 0.57-0.99]; p < 0.001). We found no evidence of a difference in median mediastinal/pleural drainage at 4 hours postoperatively (140 [IQR 75-245] vs. 135 [IQR 94-222] mL; p = 0.85) or requirement (as a binary outcome) for packed red blood cell transfusion at 24 hours postoperatively (19 [15.8%] vs. 14 [13.1%] p = 0.69). Those in the model group had a lower median protamine dose (180 [IQR 160-210] vs. 280 [IQR 250-300] mg; p < 0.001). Important limitations of this study include an unblinded design and lack of generalisability to certain populations deliberately excluded from the study (specifically children, patients with a total body weight >120 kg, and patients requiring therapeutic hypothermia to <28°C). CONCLUSIONS: Using a mathematical model to guide protamine dosing in patients following CPB improved TEG r-time and reduced the dose administered relative to a fixed ratio. No differences were detected in postoperative mediastinal/pleural drainage or red blood cell transfusion requirement in our cohort of low-risk patients. TRIAL REGISTRATION: ClinicalTrials.gov Unique identifier NCT03532594.

Challenges of antithrombotic therapy in the management of cardiovascular disease in patients with inherited bleeding disorders: A single-centre experience.

INTRODUCTION: Cardiovascular events in patients with inherited bleeding disorders are challenging to manage. The risk of bleeding secondary to antithrombotic treatment must be balanced against the risk of thrombosis secondary to haemostatic therapy. METHODS: Patients with inherited bleeding disorders with coronary artery bypass grafting (CABG), percutaneous coronary intervention (PCI) or atrial fibrillation (AF) from a single centre (2010-2018) are included. RESULTS: A total of 11 patients undergoing CABG (n = 3), PCI (n = 5) or with AF (n = 3) and a diagnosis of haemophilia A (n = 8), haemophilia B (n = 1), factor XI deficiency (n = 1) and von Willebrand disease (n = 1) managed by a multidisciplinary team are reported. In patients undergoing CABG, factor levels were normalized for 7-10 days with trough levels of 70-80% with severe patients continuing high-dose factor prophylaxis (trough 20-30%) three weeks post-operatively with daily aspirin. In a patient with mild haemophilia A and an inhibitor, recombinant factor VIIa dosing was monitored with thromboelastometry. For PCI, a 3rd-generation drug-eluting stent with one month of dual antiplatelet therapy in addition to high-dose prophylaxis as needed was preferred. Patients with AF and severe haemophilia did not receive antithrombotic treatment, and a thrombin generation assay was used to guide heparin dosing in mild haemophilia. CONCLUSION: Our experience demonstrates the importance of interdisciplinary communication to identify strategies that decrease the risk of bleeding and thrombosis. The use of extended, increased intensity prophylaxis facilitated antiplatelet therapy. Global assays may help balance the intensity of haemostatic and antithrombotic treatment.

A rare cause of culture negative bioprosthetic valve endocarditis: a case report of Aggregatibacter aphrophilus infection.

Background: The prevalence of culture negative infective endocarditis (IEC) is reported as 2-7% though this figure may be as high as 70% in developing countries.1 This higher rate will, at least in part, be due to reduced diagnostic facilities though some data suggests higher rates even when appropriate cultures were taken. The frequency is significantly elevated in patients who have already been exposed to antibiotics prior to blood cultures.1 , 2 A rare cause of culture negative IEC is the HACEK group of organisms that are normal habitants of the oropharyngeal flora and account for 1-3% of native valve endocarditis.3 Aggregatibacter aphrophilus (A. aphrophilus) is a member of the HACEK group of organisms. Case summary: A 32-year-old gentleman with a previous bioprosthetic aortic valve presented with a 1-week history of diarrhoea, vomiting, malaise, and weight loss. He was awaiting redo surgery for stenosis of the bioprosthesis, which had been inserted aged 17 for aortic stenosis secondary to a bicuspid valve. The initial blood tests revealed liver and renal impairment with anaemia. A transoesophageal echocardiogram demonstrated a complex cavitating aortic root abscess, complicated by perforation into the right ventricle. He underwent emergency redo surgery requiring debridement of the aortic abscess, insertion of a mechanical aortic prosthesis (St Jude Medical, USA), annular reconstruction and graft replacement of the ascending aorta. Despite antibiotic therapy, he remained septic with negative blood and tissue cultures. Bacterial 16S rRNA gene sequencing confirmed A. aphrophilus infection, for which intravenous ceftriaxone was initiated. This was subsequently changed to ciprofloxacin due to neutropenia. The patient self-discharged from the hospital during the third week of antibiotic therapy. One week later, he was re-admitted with fever, night sweats, and dyspnoea. Transthoracic echocardiogram revealed a large recurrent aortic abscess cavity around the aortic annulus fistulating into the right heart chambers; this was confirmed by a computed tomography scan. There was dehiscence of the patch repair. Emergency redo aortic root replacement (25 mm mechanical valve conduit, ATS Medical, USA) and annular reconstruction was performed with venoarterial extracorporeal membrane oxygenation (VA-ECMO) support. VA-ECMO was weaned after 3 days. The patient completed a full course of intravenous meropenem and ciprofloxacin and made a good recovery. Discussion: IEC with oropharyngeal HACEK organisms is rare and difficult to diagnose, due to negative blood culture results. The broad-range polymerase chain reaction and gene sequencing with comparison to the DNA database is useful in these circumstances. This case demonstrates the importance of the 16S rRNA gene sequencing for HACEK infection diagnosis and appropriate antibiotic treatment.

Minimally invasive extracorporeal circulation is a cost-effective alternative to conventional extracorporeal circulation for coronary artery bypass grafting: propensity matched analysis.

INTRODUCTION: Minimally invasive extracorporeal circulation has developed with the aim of reducing the impact of the adverse effects associated with conventional extracorporeal circulation. The aim of this study was to compare outcomes for patients undergoing coronary artery bypass grafting using minimally invasive extracorporeal circulation with those performed using conventional extracorporeal circulation. METHODS: A retrospective analysis was performed of patients undergoing minimally invasive extracorporeal circulation coronary artery bypass grafting at a single centre. 2:1 propensity matching was performed to identify control patients undergoing conventional extracorporeal circulation coronary artery bypass grafting. Outcomes were compared using univariate analysis. RESULTS: A total of 354 patients were included in the study, with 118 patients undergoing minimally invasive extracorporeal circulation coronary artery bypass grafting. Patients were well matched on baseline characteristics. The mean logistic EuroSCORE was 3.95 ± 4.20. Operative times (3.31 ± 1.52 vs. 3.56 ± 0.73, p = 0.03) were significantly shorter in minimally invasive extracorporeal circulation cases. Patients who underwent surgery with minimally invasive extracorporeal circulation had significantly less 12-hour blood loss (322.3 ± 13.2 mL vs. 380.8 ± 15.2 mL, p < 0.01). Correspondingly, a significantly lower proportion of patients were transfused (25.8% vs. 36%, p = 0.04), and the mean number of red blood cells transfused was lower (0.45 ± 0.95 vs. 0.97 ± 2.13, p = 0.01). Similarly, the number of coagulation products administered was lower (0.161 ± 0.05 vs. 0.40 ± 0.09, p = 0.05). There was a significantly lower incidence of acute kidney injury (11.0% vs. 19.9%, p = 0.03). Minimally invasive extracorporeal circulation was associated with a £679.50 cost saving per patient. DISCUSSION: Minimally invasive extracorporeal circulation for coronary artery bypass grafting is associated with a reduced requirement for blood transfusion, reduced incidence of acute kidney injury and a significant cost saving. Minimally invasive extracorporeal circulation should be considered as an adjunct for all patients undergoing coronary artery bypass grafting.

Surgical ventricular restoration.

Left ventricular restoration surgery is a procedure designed to restore or remodel the left ventricle to its normal spherical shape and size in patients with akinetic segments of the heart, secondary to either dilated cardiomyopathy or post­infarction left ventricular aneurysm.  In this video tutorial, we present the operative technique for left ventricular restoration in the case of a 61-year-old male who developed a large left ventricular aneurysm a few months after delayed presentation of an occluded left anterior descending artery and subsequent myocardial infarction.

Isolated atrial amyloid: a potential contributor to morbidity and mortality following cardiac surgery.

OBJECTIVES: Diffuse cardiac amyloidosis is a significant diagnosis with a poor prognosis. Isolated atrial amyloidosis (IAA) is the most common form of cardiac amyloidosis caused by accumulation of alpha-atrial natriuretic peptide. IAA has been associated with dysrhythmia, but otherwise remains a poorly characterized condition. The impact of incidental IAA on postoperative outcome following cardiac surgery has not previously been reported. The purpose of this study was to examine the impact of isolated atrial amyloid on patient outcomes following cardiac surgery. METHODS: A retrospective analysis was performed of all patients having excision of the left atrial appendage during cardiac surgery at our centre over a 5-year period. Patients with histological evidence of IAA were compared to patients without this diagnosis. IAA was diagnosed by immunohistochemistry for atrial natriuretic peptide. RESULTS: A total of 167 patients underwent left atrial appendage excision and of these 26 (15.6%) were found to have IAA. Preoperative characteristics were similar between the 2 groups. A significantly greater proportion of patients with IAA experienced dysrhythmia requiring implantation of a permanent pacemaker (23.1% vs 7.8%, P = 0.03). There was also a significantly elevated incidence of perioperative death in the IAA group (11.5% vs 1.4%, P = 0.03) and inferior 1-year survival (84.6% vs 96.5%, P = 0.02). CONCLUSIONS: The presence of IAA may be associated with inferior outcomes following cardiac surgery, with increased morbidity in the early postoperative period and inferior long-term survival. Knowledge of the diagnosis preoperatively may facilitate management of patients.

Tricuspid regurgitation and the right ventricle in risk stratification and timing of intervention.

Tricuspid regurgitation natural history and treatment remains poorly understood. Right ventricular function is a key factor in determining prognosis, timing for intervention and longer-term outcome. The right ventricle is a thin walled chamber with a predominance of longitudinal fibres and a shared ventricular septum. In health, the low-pressure pulmonary circulation results in a highly compliant RV well equipped to respond to changes in preload but sensitive to even small alterations in afterload. In Part 1 of this article, discussion focuses on key principles of ventricular function assessment and the importance of right ventricular chamber size, volumes and ejection fraction, particularly in risk stratification in tricuspid regurgitation. Part 2 of this article provides an understanding of the causes of tricuspid regurgitation in the contemporary era, with emphasis on key patient groups and their management.

Use veno-venous extra corporeal membrane oxygenation in elderly patients with post-cardiotomy hypoxia: the changing paradigm of respiratory support in adult respiratory distress syndrome.

BACKGROUND: Veno-venous extracorporeal membrane oxygenation (VV-ECMO) support for ARDS treatment after cardiac surgery has progressed remarkably in the last 20 years. However, one of the limitations of a successful recover is age, being a powerful predictor of mortality. CASE PRESENTATION: In this case report we discuss a 78-year-old man who underwent aortic valve and aortic root replacement. The postoperative period was complicated by ARDS following aspiration pneumonia treated with VV-ECMO weaned after 6 days. At two-year follow up, the patient made an excellent recover, being the second oldest person to survive VV-ECMO following cardiac surgery in the world. CONCLUSION: In the literature there is no consensus regarding a specific age limit and results, in the use of ECMO in the elderly are scarce and inconsistent. We do not think advanced age is a contraindication to the use of ECMO.

Does liver cirrhosis lead to inferior outcomes following cardiac surgery?

A best evidence topic in cardiac surgery was written according to a structured protocol. The question addressed was: Do patients with liver cirrhosis undergoing cardiac surgery have inferior clinical outcomes? Altogether, 1627 papers were found using the reported search, of which 8 represented the best evidence to answer the clinical question. The authors, journal, date and country of publication, patient group studied, study type, relevant outcomes and results of these papers are tabulated. We conclude that these studies demonstrate that cirrhotic patients have significantly poorer clinical outcomes following cardiac surgery than would be predicted by conventional risk scoring systems. This includes both in-hospital mortality and rates of major complications (bleeding, cardiac, infective, renal and respiratory), which would likely lead to an increased hospital length of stay and, therefore, an associated cost. Evidence supports that the Model for End-stage Liver Disease and Child-Turcotte-Pugh cirrhosis severity scoring systems can be used to stratify risk in cirrhotic patients undergoing cardiac surgery and should be considered for inclusion in future cardiac surgery risk scoring systems.

Does the use of a hot-shot lead to improved outcomes following adult cardiac surgery?

A best evidence topic in cardiac surgery was written according to a structured protocol. The question addressed was: Does the use of a 'hot-shot' (terminal warm blood cardioplegia) lead to improved outcomes following adult cardiac surgery? Altogether, 567 papers were found using the reported search, of which 9 represented the best evidence to answer the clinical question. The authors, journal, date and country of publication, patient group studied, study type, relevant outcomes and results of these papers are tabulated. We conclude that evidence supporting the use of a hot-shot prior to weaning from cardiopulmonary bypass is rather limited. All 8 of the randomized trials to date are small studies which examine heterogeneous groups of patients, and unfortunately, the conclusions are inconsistent, perhaps in part related to the inability to demonstrate statistical significance with small group size. From the evidence, it appears likely that the use of a hot-shot results in more rapid biochemical, electrical and possibly functional myocardial recovery from cardiopulmonary bypass. However, no study has been able to demonstrate that this leads to improved clinical outcomes other than lower incidence of atrial fibrillation.

Long-Term Outcome of Patients Undergoing Minimally Invasive Direct Coronary Artery Bypass Surgery: A Single-Center Experience.

OBJECTIVE: The primary objective was to investigate the long-term survival of patients who underwent single-vessel coronary revascularization with minimally invasive direct coronary artery bypass surgery with or without hybrid revascularization. The secondary outcome measures were repeat revascularization either by coronary artery bypass grafting or by percutaneous coronary intervention and the incidence of myocardial infarction or recurrent angina. METHODS: This is a retrospective study of prospectively collected data of patients who underwent minimally invasive direct coronary artery bypass procedure in our center between January 2001 and December 2015. Procedures were performed either through small left anterolateral thoracotomy or lower midline sternotomy. RESULTS: A total of 182 patients were identified: 100 underwent minimally invasive direct coronary artery bypass to the left anterior descending artery and 82 underwent hybrid revascularization (percutaneous coronary intervention to coronary arteries other than the left anterior descending artery along with minimally invasive direct coronary artery bypass to the left anterior descending artery). The mean ± SD age was 62 ± 10.1 years. Preoperatively 82% were male, and 72.5% patients had good left ventricular function. The median follow-up period was 10.9 years. There was no in-hospital or 30-day mortality. The 10-year actuarial survival was 84.8%. Freedom from repeat revascularization was 98.9% at 1 year and 89.9% at 10 years. At follow-up, freedom from myocardial infarction was 96.7% whereas freedom from angina was 92.9%. CONCLUSIONS: Within the limitations imposed by retrospective analyses, our study demonstrates excellent long-term outcome in patients undergoing minimally invasive direct coronary artery bypass with or without hybrid revascularization. For isolated left anterior descending artery disease minimally invasive direct coronary artery bypass should be considered, whereas hybrid revascularization (percutaneous coronary intervention and minimally invasive direct coronary artery bypass) should be considered for multivessel disease.

Molecular mechanisms of myocardial nitroso-redox imbalance during on-pump cardiac surgery.

BACKGROUND: The mechanism responsible for left ventricular dysfunction after cardiac surgery is only partly understood. In isolated rat hearts subjected to an ischaemia-reperfusion protocol, left ventricular dysfunction was associated with uncoupling of endothelial nitric oxide synthase (NOS) activity secondary to oxidation of the NOS cofactor, tetrahydrobiopterin (BH4). Here we investigated the effect of cardiopulmonary bypass and reperfusion on myocardial nitroso-redox balance in patients undergoing cardiac surgery. METHODS: From 116 patients who underwent elective cardiac surgery on cardiopulmonary bypass, paired samples of the right atrial appendages were obtained before venous cannulation of the right atrium and after myocardial reperfusion. Superoxide production from atrial samples was measured by lucigenin (5 µmol/L) enhanced chemiluminescence and 2-hydroxyethidium (2-OHE) detection by high-performance liquid chromatography (HPLC). BH4, oxidised biopterins, GTP-cyclohydrolase 1 (GTPCH-1, the rate-limiting enzyme in BH4 synthesis), and NOS activity ((14)C L-arginine to L-citrulline conversion) were measured by HPLC. FINDINGS: Atrial superoxide production increased significantly after reperfusion (from mean 37·83 relative light units per s per mg [SE 3·71] before cannulation to 65·02 [6·01] after reperfusion, p<0·0001; n=46 samples from 23 patients) due to increased mitochondrial and NOX2 oxidase activity (by 309% and 149%; p=0·002 and p=0·0002, respectively) and uncoupling of NOS activity. Atrial content of BH4 after perfusion was reduced (by 32%, p=0·001), as was activity of GTPCH1 (50%, p<0·0001). NOS activity decreased significantly after reperfusion (60%, p=0·0005) and this reduction was not affected by BH4 supplementation (10 µM) or NOX2 inhibition ex vivo. Instead, we identified increased endothelial NOS s-glutathionylation as the main mechanism for NOS uncoupling after reperfusion. Reversing NOS s-glutathionylation with dithiothreitol (100 µmol/L) completely restored NOS activity after reperfusion (p=0·34). INTERPRETATION: Our findings suggest that NOS s-glutathionylation, rather than BH4 depletion, accounts for NOS dysfunction in patients after cardiac surgery and cardiopulmonary bypass. FUNDING: British Heart Foundation.