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OBJECTIVES Cardiac surgery with hypothermic circulatory arrest (HCA) is associated with neurological morbidity of variable severity and electroencephalography (EEG) is a sensitive proxy measure of brain injury. We conducted a narrative review of the literature to evaluate the role of perioperative EEG monitoring in cardiac surgery involving HCA. METHODS Medline, Embase, Central and LILACS databases were searched to identify studies utilizing perioperative EEG during surgery with HCA in all age groups, published since 1985 in any language. We aimed to compare EEG use with no use but due to the lack of comparative studies, we performed a narrative review of its utility. Two or more reviewers independently screened studies for eligibility and extracted data. RESULTS Fourty single-centre studies with a total of 3287 patients undergoing surgery were identified. Most were observational cohort studies (34, 85%) with only 1 directly comparing EEG use with no use. EEG continuity (18, 45%), seizures (15, 38%) and electrocerebral inactivity prior to circulatory arrest (15, 38%) were used to detect, monitor, prevent and prognose neurological injury. Neurological dysfunction was reported in almost all studies and occurred in 0–21% of patients. However, the heterogeneity of reported clinical and EEG outcome measures prevented meta-analysis. CONCLUSIONS EEG is used to detect cortical ischaemia and seizures and predict neurological abnormalities and may guide intraoperative cerebral protection. However, there is a lack of comparative data demonstrating the benefit of perioperative EEG monitoring. Use of a standardized methodology for performing EEG and reporting outcome metrics would facilitate the conduct of high-quality clinical trials.

Objectives Cardioplegia is the primary method for myocardial protection during cardiac surgery. We conducted a systematic review of randomized controlled trials of cardioplegia in children to evaluate the current evidence base. Methods We searched MEDLINE, CENTRAL and LILACS and manually screened retrieved references and systematic reviews to identify all randomized controlled trials comparing cardioplegia solutions or additives in children undergoing cardiac surgery published in any language; secondary publications and those reporting inseparable adult data were excluded. Two or more reviewers independently screened studies for eligibility and extracted data; the Cochrane Risk of Bias tool was used to assess for potential biases. Results We identified 26 trials randomizing 1596 children undergoing surgery; all were single-centre, Phase II trials, recruiting few patients (median 48, interquartile range 30–99). The most frequent comparison was blood versus crystalloid in 10 (38.5%) trials, and the most common end points were biomarkers of myocardial injury (17, 65.4%), inotrope requirements (15, 57.7%) and length of stay in the intensive care unit (11, 42.3%). However, the heterogeneity of patients, interventions and reported outcome measures prohibited meta-analysis. Overall risk of bias was high in 3 (11.5%) trials, unclear in 23 (88.5%) and low in none. Conclusions The current literature on cardioplegia in children contains no late phase trials. The small size, inconsistent use of end points and low quality of reported trials provide a limited evidence base to inform practice. A core outcome set of clinically important, standardized, validated end points for assessing myocardial protection in children should be developed to facilitate the conduct of high-quality, multicentre trials.

Objective The most durable valved right ventricle to pulmonary artery conduit for the repair of congenital heart defects in patients of different ages, sizes, and anatomic substrate remains uncertain. Methods We performed a retrospective analysis of 4 common right ventricle to pulmonary artery conduits used in a single institution over 30 years, using univariable and multivariable models of time-to-failure to analyse freedom from conduit dysfunction, reintervention, and replacement. Results Between 1988 and 2018, 959 right ventricle to pulmonary artery conduits were implanted: 333 aortic homografts, 227 pulmonary homografts, 227 composite porcine valve conduits, and 172 bovine jugular vein conduits. Patients weighed 1.6 to 98.3 kg (median 15.3 kg), and median duration of follow-up was 11.4 years, with 505 (52.2%) conduits developing dysfunction, 165 (17.2%) requiring catheter intervention, and 415 (43.2%) being replaced. Greater patient weight, conduit z-score, type and position, as well as catheter intervention were predictors of freedom from replacement. Multivariable analysis demonstrated inferior durability for smaller composite porcine valve conduits, with excellent durability for larger diameter conduits of the same type. Bovine jugular vein conduit longevity was inferior to that of homografts in all but the smallest patients. Freedom from dysfunction at 8 years was 60.7% for aortic homografts, 72% for pulmonary homografts, 51.2% for composite porcine valve conduits, and 41.3% for bovine jugular vein conduits. Judicious oversizing of the conduit improved conduit durability in all patients, but to the greatest extent in patients weighing 5 to 20 kg. Conclusions Pulmonary and aortic homografts had greater durability than xenograft conduits, particularly in patients weighing 5 to 20 kg. Judicious oversizing was the most significant surgeon-modifiable factor affecting conduit longevity.

To examine the role and outcomes of all interventions for aortic stenosis in children, with focus on freedom from reintervention and the aim to minimise prosthetic aortic valve replacement (pAVR) during childhood. Retrospective analysis of 194 consecutive children who underwent any aortic valve intervention for a biventricular repair strategy at a single institution between 1995 and 2017. Data were obtained from hospital records and follow-up was 100% complete. Over a 22-year period, 194 children underwent total 313 aortic valve procedures: Primary interventions were surgical valvotomy (SV)/surgical repair (SR) in 94 (48.5%), balloon valvuloplasty (BV) in 60 (30.9%), pAVR in 8 (4.1%) and Ross/Ross-Konno procedure in 32 (16.5%). Median age at first intervention was 1.1 years (interquartile range [IQR] 0.1-9.4) and varied with type of intervention: SV/SR were most common in neonates (33, 75%) and infants (35, 68%), whilst BV was most frequent in older children (42, 42%). Operative survival was 99% (2 early deaths, both in neonates with critical aortic stenosis and poor left ventricular function) and 15-year survival was 95%. A Ross procedure was performed in 79 (40.7%) patients over the 15-year study period, 1 of whom required late pAVR for autograft failure. Freedom from any reintervention after SV/SR and BV was 41% and 40% at 10 years, compared to 90% at 10 years with the Ross procedure (P0.001). Among neonatal SV/SR and BV, 98% required reintervention during childhood with no difference between groups. Valve morphology did not influence freedom from ultimate valve replacement. In patients who went on to have a Ross procedure, median time from initial intervention to Ross was 2.8 years (IQR 0.1-11.9) in neonates and 6.0 years (IQR 3.1-7.5) in all other age groups. Overall freedom from pAVR was 97% at 10 years and was similar in the SV/SR and BV groups. A strategy of simple valve repair and primary Ross procedure provides excellent survival and good freedom from pAVR. However, reintervention rates after simple interventions for congenital AS are high, especially in younger age groups. The Ross procedure offers the best freedom from reintervention of any technique and wider use of primary Ross in younger age groups should be considered.

There is close interaction between the functions of the liver and heart affecting the presentation, diagnosis, and outcome of acute and chronic cardiac and liver disease. Conditions affecting both organ systems should be considered when proposing transplantation because the interaction between cardiac disease and liver disease has implications for diagnosis, management, selection for transplantation, and, ultimately, for longterm outcomes after liver transplantation (LT). The combination of cardiac and liver disease is well recognized in adults but is less appreciated in pediatric patients. The focus of this review is to describe conditions affecting both the liver and heart and how they affect selection and management of LT in the pediatric population.

OBJECTIVES: We sought to define the early and late outcomes of unifocalization based on a classification of the native pulmonary artery (nPA) system and major aortopulmonary collateral arteries (MAPCAs) with a policy of combined recruitment and rehabilitation and to analyse the role of unifocalization by leaving the ventricular septal defect (VSD) open with a limiting right ventricle-pulmonary artery (RV-PA) conduit in borderline cases. METHODS: An analysis of 271 consecutive patients assessed for unifocalization at a single institution between 1988 and 2016 was performed. Patients were classified according to the pulmonary blood supply: group A, unifocalization based on nPA only; group B, based on nPA and MAPCAs; group C, MAPCAs only (absent nPAs). RESULTS: Unifocalization was achieved in 249 (91.9%) cases with an early mortality of 2.8%. Group A included 72 (28.9%) patients, group B 119 (47.8%) patients and group C 58 (23.3%) patients with no difference in early survival between groups. Survival at 5, 10 and 15 years was 90.0% (85.9–94.3), 87.2% (83.5–91.2) and 82.3% (75.2–89.9), respectively. Late survival in groups A and B was similar but 10- and 15-year survival in group C decreased to 79.2% (68.2–92.1) and 74.3% (61.1–90.4) (P = 0.02), respectively. A mean of 1.9 (±0.6) MAPCAs were recruited per patient (range 0–6). The VSD was left open with a limiting RV-PA conduit in 97 (39.0%) cases, but subsequently closed in 48 patients, giving a total of 200 (80.3%) patients achieving VSD closure (full repair). Delaying VSD closure was not associated with increased risk for early or late survival. A central shunt to rehabilitate the nPAs was used in 56 (22.5%) cases. This was associated with a reduction in the number of MAPCAs recruited, but still required a mean of 1.8 (±0.5) MAPCAs recruited per patient to achieve unifocalization. In multivariate risk analysis, those suitable for single-stage full repair had the best long-term outcomes. Group C anatomy was associated with poor late survival compared to groups A and B (hazard ratio 2.7). CONCLUSIONS: Survival is maximized by a combined approach of rehabilitation and recruitment. MAPCAs should always be recruited if they supply areas with absent nPA supply. A strategy of leaving the VSD open with a limiting RV-PA conduit is a safe and effective way of managing borderline cases.

Patients undergoing cardiac surgery require adequate myocardial protection. Manipulating myocardial metabolism may improve the extent of myocardial protection. Perhexiline has been shown to be an effective anti-anginal agent due to its metabolic modulation properties by inhibiting the uptake of free fatty acids into the mitochondrion, and thereby promoting a more efficient carbohydrate-driven myocardial metabolism. Metabolic modulation may augment myocardial protection, particularly in patients with left ventricular hypertrophy (LVH) known to have a deranged metabolic state and are at risk of poor postoperative outcomes. This study aimed to evaluate the role of perhexiline as an adjunct in myocardial protection in patients with LVH secondary to aortic stenosis (AS), undergoing an aortic valve replacement (AVR).In a multicentre double-blind randomized controlled trial of patients with AS undergoing AVR ± coronary artery bypass graft surgery, patients were randomized to preoperative oral therapy with either perhexiline or placebo. The primary end point was incidence of inotrope use to improve haemodynamic performance due to a low cardiac output state during the first 6 h of reperfusion, judged by a blinded end points committee. Secondary outcome measures included haemodynamic measurements, electrocardiographic and biochemical markers of new myocardial injury and clinical safety outcome measures.The trial was halted early on the advice of the Data Safety and Monitoring Board. Sixty-two patients were randomized to perhexiline and 65 to placebo. Of these, 112 (54 perhexiline and 48 placebo) patients received the intervention, remained in the trial at the time of the operation and were analysed. Of 110 patients who achieved the primary end point, 30 patients (16 perhexiline and 14 placebo) had inotropes started appropriately; there was no difference in the incidence of inotrope usage OR of 1.65 [confidence interval (CI): 0.67-4.06] P = 0.28. There was no difference in myocardial injury as evidenced by electrocardiogram odds ratio (OR) of 0.36 (CI: 0.07-1.97) P = 0.24 or postoperative troponin release. Gross secondary outcome measures were comparable between the groups.Perhexiline as a metabolic modulator to enhance standard myocardial protection does not provide an additional benefit in haemodynamic performance or attenuate myocardial injury in the hypertrophied heart secondary to AS. The role of perhexiline in cardiac surgery is limited.

Intramural coronary arteries remain a major risk factor and technical challenge of the arterial switch operation for transposition of the great arteries. We report a 27-year-old woman who presented with acute coronary syndrome late after arterial switch with a complex coronary pattern (intramural left and right coronary from sinus 2). Computed tomography demonstrated that the pericardial 'saddle bag' used to reconstruct the intramural coronary was compressed between the neoaortic root and the neopulmonary trunk. During surgery, the coronary system was laid open into the neoaorta with patch enlargement, and the patient made an uneventful recovery.

A 38-year-old man presented with a history of influenza-like symptoms and a persistent dry cough. He had been previously fit and well, other than a road traffic collision 20 years ago, in which he sustained bilateral pneumothoraces, left hemidiaphragm injury with herniation of the stomach into the left hemithorax and splenic injury. He therefore had undergone an emergency laparotomy, splenectomy and repair of the left hemidiaphragm. He was a non-smoker and denied contact with TB or asbestos. Physical examination was unremarkable other than a laparotomy scar. Chest radiograph showed a large opacity behind the cardiac silhouette suspicious for primary lung cancer (figure 1A). CT of the thorax and abdomen confirmed a 41 mm soft tissue mass in the left lower …

s / International Journal of Surgery 12 (2014) S13eS117 S76 0313: ADVANCES IN TRAINING: A HIGH FIDELITY PRACTICAL COURSE ON CADAVERS FOR COMPLEX CARDIAC PROCEDURES John Massey, Jasmine Winter-Beatty , Nigel Drury, Jitendra Parmar. University Hospital Coventry and Warwickshire, Coventry, UK. Introduction: Surgical education is changing owing to implementation of European Working time Directive. Cadaveric-based educational programs have had positive feedback from surgical trainees. Our training centre allows trainees to gain experience in complex cardiac procedures in a safe, non-time pressurised environment.We look at how trainees benefit from a high fidelity course-training surgeons to perform two complex cardiac procedures. Methods: Cadavers had been prepared through a midline sternotomy, pericardium opened with heart and great vessels exposed. Trainees performed a stentless aortic valve replacement and an aortic root replacement. Faculty surgeons facilitated learning as required. Results: There was a 100% response for a post course feedback form. Knowledge survey revealed an increase in perception of knowledge. There was an increase in trainees' confidence to assist these procedures in future. 100% of attendees would recommend it to their peers. Trainees stated that they felt more comfortable assisting and performing the procedures having practiced on cadavers. Conclusions: Simulated training using fresh frozen human cadavers can be incorporated into surgical training of cardiothoracic trainees. Such a course can have high face validity and significantly improve trainees' perception of technical knowledge as well as increasing confidence to assist and perform complex cardiac procedures. 0320: THE LESSER-SPOTTED MEDICAL STUDENT: UNDERSTANDING AND FACILITATING STUDENT PRESENCE ON WARDS Ian Henderson, Jessika Voll , Damian Bragg. Queen's Medical Centre (NUH)

OBJECTIVES Perhexiline is thought to modulate metabolism by inhibiting mitochondrial carnitine palmitoyltransferase-1, reducing fatty acid uptake and increasing carbohydrate utilization. This study assessed whether preoperative perhexiline improves markers of myocardial protection in patients undergoing coronary artery bypass graft surgery and analysed its effect on the myocardial metabolome. METHODS In a prospective, randomized, double-blind, placebo-controlled trial, patients at two centres were randomized to receive either oral perhexiline or placebo for at least 5 days prior to surgery. The primary outcome was a low cardiac output episode in the first 6 h. All pre-specified analyses were conducted according to the intention-to-treat principle with a statistical power of 90% to detect a relative risk of 0.5 and a conventional one-sided α-value of 0.025. A subset of pre-ischaemic left ventricular biopsies was analysed using mass spectrometry-based metabolomics. RESULTS Over a 3-year period, 286 patients were randomized, received the intervention and were included in the analysis. The incidence rate of a low cardiac output episode in the perhexiline arm was 36.7% (51/139) vs 34.7% (51/147) in the control arm [odds ratio (OR) 0.92, 95% confidence interval (CI) 0.56–1.50, P = 0.74]. Perhexiline was associated with a reduction in the cardiac index at 6 h [difference in means 0.19, 95% CI 0.07–0.31, P = 0.001] and an increase in inotropic support in the first 12 h (OR 0.55, 95% CI 0.34–0.89, P = 0.015). There were no significant differences in myocardial injury with troponin-T or electrocardiogram, reoperation, renal dysfunction or length of stay. No difference in the preischaemic left ventricular metabolism was identified between groups on metabolomics analysis. CONCLUSIONS Preoperative perhexiline does not improve myocardial protection in patients undergoing coronary surgery and in fact reduced perioperative cardiac output, increasing the need for inotropic support. Perhexiline has no significant effect on the mass spectrometry-visible polar myocardial metabolome in vivo in humans, supporting the suggestion that it acts via a pathway that is independent of myocardial carnitine palmitoyltransferase inhibition and may explain the lack of clinical benefit observed following surgery. ClinicalTrials.Gov ID NCT00845364.

Objective: Defibrillation pads are used routinely at both cardiac arrests and cardioversion procedures. There are currently no evidence-based guidelines on how often pads should be replaced, although it has been suggested that they should be changed as often as every three shocks to maintain optimal performance. Previously, we have shown that on exposure to air, pad mass diminishes over time due to evaporation—an effect likely to lead to poorer conduction between skin and paddle. This prospective study was designed to determine if evaporation is accelerated by the passage of a defibrillation current and to formulate evidence-based guidelines for defibrillation pad replacement. Materials and methods: 3M defibrillation pads (2346N) were collected from acute wards and emergency departments in two hospitals in the UK over a 2 month period. The duration of exposure to air, number and energy of shocks, and type of procedure were recorded. When no longer required, pad masses were determined and the loss of pad mass due to evaporation calculated. Results: 26 pairs of pads were collected from 14 cardiac arrests and 12 cardioversions. The total defibrillation energy used ranged from 150 to 5080 J and evaporative drying time from 4 to 38 min. The rate of evaporation from these pads (86.1 mg min −1 ) was not significantly different from pads previously studied on volunteers in the absence of a defibrillation current (99.4 mg min −1 ). Of the defibrillation pads exposed to air for less than 30 min, in only one of 49 pads was the loss of mass due to evaporation consistent with a significant increase in transthoracic impedance (TTI). Correspondingly, of two pads used for more than 30 min, both attained a mass consistent with a significant increase in TTI. Conclusions: Defibrillation pads can be used for up to 30 min without evaporation causing a clinically significant increase in TTI. The passage of a defibrillation current across pads does not further accelerate water loss.

Objective: In order to minimise transthoracic impedance (TTI) during defibrillation, water-based pads are used to improve conductivity between metal defibrillation paddles and skin. Subjectively, these pads appear to dry very quickly; an effect that may lead to an increase in TTI due to poorer conduction between paddles and skin. This study was carried out to assess the effect of evaporative drying of defibrillation pads on TTI. Materials and methods: TTI was measured at 5–10 min intervals in 20 adult male volunteers across 3M defibrillation pads (2346N) placed in the anterior–apical position. Measurements of TTI were made at 30 kHz using a Bodystat® MultiScan 5000 monitor at end-expiration. A third pad was placed on the left precordium and its mass recorded each time a TTI measurement was made. Results: The median age of subjects was 22 years (range 21–52 years) and their median body mass index was 23.1 kg m −2 (range 18.4–42.8 kg m −2 ). Median room temperature was 23.0°C (range 19.0–24.0°C) and the median humidity was 31.0% (range 28.0–48.0%). 3M defibrillation pads had an initial mean mass of 25.14 g (S.D.±0.41 g). Changes in defibrillation pad mass due to evaporative loss occurred immediately and rapidly, with all measurements being significantly lower than the baseline value. Mean baseline TTI was 63.6 Ω (S.D.±13.7 Ω). After 30 min a statistically significant ( P =0.012) rise of 1.4 Ω (2.2%), was observed corresponding to a 12.6% decrease in pad mass, after which TTI continued to increase in a linear fashion. Conclusion: In the absence of a defibrillation current, 3M defibrillation pads can safely be left on the chest wall for at least 25 min in a typical hospital environment before evaporative drying results in a significant increase in transthoracic impedance.

An elderly man presented to the AE it was easily removed and the puncture site repaired under direct vision with a pledgeted 3/0 polypropylene suture. The patient made an uneventful recovery and was transferred back to his local hospital for further management. Discussion

Although the presentation of original research to learned societies is valuable, the target should be publication in a peer-reviewed journal. Therefore, the strength of a meeting may be assessed by the rate of the subsequent publication of papers from the presented abstracts. We conducted an analysis of abstracts presented at consecutive annual meetings of the Society for Cardiothoracic Surgery (SCTS) in Great Britain and Ireland over a 15-year period. Abstract books and other documentation from the 1993-2007 meetings were reviewed; abstracts from other major Cardiothoracic Surgery meetings held in 2007 were also reviewed. Medline was searched to identify the peer-reviewed publications arising from each work presented. For abstracts presented at SCTS in 2003-07, the factors potentially associated with publication were analysed by logistic regression. If no publications were identified, authors were contacted through a standardized email questionnaire to ascertain its status and reasons for non-publication. Over the 15-year period, 909 abstracts were presented at the SCTS meetings. The rate of publication rose from ~30% in the mid-1990s to consistently60% from recent meetings, with a high of 81.3% from 2006. However, in comparison with other Cardiothoracic Surgery meetings in 2007, the chance of subsequent publication from SCTS (66.7%) was lower than from the European Association for Cardio-Thoracic Surgery (75.0%), the American Association for Thoracic Surgery (83.9%) and The Society of Thoracic Surgeons (72.5%) meetings. For abstracts presented at the last five SCTS meetings, publication was most commonly in a speciality journal (56.3%) and the median time for publication was 15 months (range -24 to 63 months) with 14 papers published prior to presentation at the meeting. On regression analysis, the only factor associated with publication was the study design comparing randomized trials and systematic reviews with other types of study (P0.01). Of the 90 unpublished abstracts, 48 (53.3%) authors replied to an email questionnaire revealing that 41 (85.4%) were never submitted for publication. The most common reasons given were low priority (29.6%) and low likelihood of acceptance (24.1%). In recent years, the annual meeting of the Society has become a forum for the presentation of high-quality research that usually withstands peer-review, most commonly in a speciality journal. The rate of publication has increased to consistently60%, although those that remain unpublished are generally never submitted. This compares favourably with national meetings of other surgical societies, although it is lower than other major cardiothoracic meetings which have an affiliated journal. At a time when it has been suggested that medical research in the UK is in decline, cardiothoracic surgery appears to be thriving.

Neonatal aortic stenosis is a complex and heterogeneous condition, defined as left ventricular outflow tract obstruction at valvular level, presenting and often requiring treatment in the first month of life. Initial presentation may be catastrophic, necessitating hemodynamic, respiratory and metabolic resuscitation. Subsequent management is focused on maintaining systemic blood flow, either via a univentricular Norwood palliation or a biventricular route, in which the effective aortic valve area is increased by balloon dilation or surgical valvotomy. In infants with aortic annular hypoplasia but adequately sized left ventricle, the Ross-Konno procedure is also an attractive option. Outcomes after biventricular management have improved in recent years as a consequence of better patient selection, perioperative management and advances in catheter technology. Exciting new developments are likely to significantly modify the natural history of this disorder, including fetal intervention for the salvage of the hypoplastic left ventricle; 3D echocardiography providing better definition of valve morphology and aiding patient selection for a surgical or catheter-based intervention; and new transcutaneous approaches, such as duel beam echo, to perforate the valve.

BACKGROUND: In minimally invasive surgery, there is increased reliance on real-time 2-dimensional images. The fibre-optic light lead is one of the most frequently damaged elements of the 'imaging chain', leading to a poor quality picture. METHODS: Light leads with a honeycomb projection were connected to a light source and the resulting beam directed at a sheet of paper. Darkened sectors with diminished or absent light transmission were recorded. RESULTS: All suitable light leads in routine use were examined. A mean of 22.2% (SD 7.8%) of the projection had diminished or absent light transmission. CONCLUSION: Sub-optimal endoscopic equipment was in routine use.

Congenital defects of the pericardium are rare, but when they are reported they are frequently associated with other cardiac lesions. We describe a case of partial pericardial defect found incidentally at surgery for closure of an ostium primum atrial septal defect. Proposed mechanisms of pericardial defect development are discussed and we suggest that associations with congenital and acquired heart disease are mostly circumstantial.

Chronic myelomonocytic leukaemia is an atypical myeloproliferative disorder with a natural history of progression to acute myeloid leukaemia, a complex and poorly understood response by the bone marrow to stress. Cardiac surgery activates many inflammatory cascades and may precipitate a systemic inflammatory response syndrome. We present a case of undiagnosed chronic myelomonocytic leukaemia who developed rapidly fatal multi-organ dysfunction following cardiac surgery due to an acute leukaemoid reaction.