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OBJECTIVES Right heart failure (RHF) is a major complication following left ventricular assist device (LVAD) implantation. Pulmonary artery pulsatility index (PAPi) has been evaluated as a haemodynamic marker for RHF, but PAPi is dependent on pulmonary vascular resistance (PVR). We conducted a systematic review to assess the relationship between PAPi and RHF and death in patients undergoing LVAD implantation and examined the relationship between PAPi cut-off and PVR. METHODS We searched PubMed, EMBASE, CENTRAL and manually screened retrieved references to identify all clinical studies reporting PAPi in adult patients with a durable LVAD. Eligibility criteria were prespecified and 2 reviewers independently screened and extracted data; the Newcastle–Ottawa Scale was used to assess quality of non-randomized studies. This study was prospectively registered on PROSPERO (CRD42021259009). RESULTS From 283 unique records, we identified 16 studies reporting haemodynamic assessment in 20 634 adult patients with an implanted durable LVAD. Only 2 studies reported on mortality and in both, a lower PAPi was significantly associated with death. Fifteen studies reported RHF data and, in 10 studies, a lower PAPi was significantly associated with RHF. Six studies reported on PAPi cut-offs ranging from 0.88 to 3.3; and the cut-offs were directly related to PVR (r = 0.6613, P = 0.019). CONCLUSIONS Lower PAPi was associated with RHF and death following LVAD implantation, but a single PAPi cut-off cannot be defined, as it is dependent on PVR.

Background Complex pulmonary atresia with a ventricular septal defect and major aortopulmonary collateral arteries (PA VSD MAPCA) is a rare and complex form of congenital heart disease. Staged surgical palliation is carried out in childhood, and in expert centres, is associated with good medium term survival. Adult outcomes following transition to adult care are not known. Purpose To establish adult outcomes of PA VSD MAPCA following repair during childhood in our institution Methods Review of clinical records for outcome data including life status, NYHA class, employment status, re-intervention in adult life, arrhythmia, pregnancy, exercise capacity and mode of death, where known. We predefined our population into two groups based on their status at transition to adult care, A) complete repair with RV-PA conduit and VSD closed and B) repaired but VSD left open. Results 188 patients from our series have transitioned to adult services. As many were tertiary referrals (nationally and internationally) the local follow up population was 53 adults (54.7% male), mean age of those alive under follow up is 27.2±6.5 years, with a mean follow up of 25.3±6.1 years. There were 43 in group A and 10 in group B. Mortality in the total population was 18.9% (10/53), group A (16.3%), group B (30.0%), mean age at death 37.5±10.3 years and 29.9±8.4 years, 6/10 deaths were sudden. 22.6% of the whole group had DiGeorge/22q11 microdeletion, with a learning deficit in 32.7% of the cohort, where this could be assessed. Reinterventions included RV-PA conduit change, coil occlusion, pacemaker implantation, ICD implantation and ablation procedures, overall 39.6% underwent reintervention in adult life. Pregnancy occurred in 33.3% of 24 female patients. 50% of individuals were found to have undertaken some form of paid work and of these 11.5% had DiGeorge. Conclusions Complex PA VSD MAPCA is associated with good late survival with late attrition including sudden death and heart failure. 22q11 is associated with learning deficit and consequent lack of employment. Non 22q11 have good educational outcomes and there is less observed deficit regarding employment. Successful pregnancy is possible within this population. Funding Acknowledgement Type of funding sources: None.

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.

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 collaborative study was conducted to evaluate a method for identifying d- or dl-∝-tocopherol in pharmaceuticals, food supplements, or feed supplements. The sample is extracted and saponified, the extraneous color is removed by chromatography, and the sample is assayed for vitamin E. Optical rotations are determined before and after formation of the ferricyanide oxidation product. The specific optical rotation of the oxidation product is negligible for the dJ-form and +25.5° for the d-form. Statistical analysis of the data reported by 8 collaborators for the standard d-∝-tocopheryl acetate and for 6 unknown samples indicates a significant interaction between laboratories and samples. The mean coefficients of variation among laboratories for the determinations of the corrected specific optical rotation of the standard and the rotation ratio for the unknown samples containing d-∝-tocopherol were 11.7 and 21.6%, respectively, for all laboratories and 5.8 and 11.8%, respectively, for experienced laboratories. This identification test for vitamin E is acceptable for determining the form of vitamin E as either d or dl, but is not acceptable for accurately determining mixtures of the 2 forms. The method has been adopted as official first action for the identification of d- or dl-∝-tocopherol.

Isolated tomato (Lycopersicon esculentum var. Kc 146) fruit mitochondria could be stored successfully in the frozen state without a cryoprotective agent if the mitochondria were frozen quickly by immersion in liquid nitrogen and later thawed quickly at 30 C. Criteria of freezing damage were rate of respiration, adenosine diphosphate to oxygen ratio, and respiratory control ratio. Marked reduction in respiration and loss of respiratory control occurred when mitochondria were transferred from liquid nitrogen to −5, −10, or −18 C for 15 minutes prior to thawing at 30 C. Dimethylsulfoxide (5%) prevented freezing damage when mitochondria were incubated at −5 C but did not prevent freezing damage at −10 or −18 C. Isolated tomato mitochondria show promise as a model system for studying the nature of freezing damage and the mode of action of cryo-protective agents.

Mitochondria from tomato fruit (Lycopersicon esculentum Mill.) exhibited a respiratory control ratio of 2.5 and an ADP:O ratio of 1.3 for succinate oxidation for 24 hours after isolation. They also showed a delay in response to the first addition of ADP. The addition of ATP and ADP before succinate eliminated the delayed response as did chelation of endogenous cations with ethylenediaminetetraacetic acid. The addition of ATP after succinate resulted in a longer delay in response than that obtained with ADP. Exogenous oxaloacetate in low concentration inhibited respiration in states 3 and 4 with succinate and resulted in delayed response to ADP. The function of adenine nucleotide during the delay in response may be to promote the metabolism of oxaloacetate or to decrease the affinity of oxaloacetate to its site of inhibition.

The stimulation of oxygen uptake in plant mitochondria uncoupled by 2,4-dinitrophenol (DNP) depends on adenine nucleotide in the absence of hexokinase (EC 2.7.1.1). Laties (9) observed this dependence with cauliflower bud mitochondria oxidizing malate, while WViskich and Bonner (13) reported a doubling of the DNP-rate of oxygen uptake by adenine nucleotide in sweet potato mitochondria oxidizing succinate. 'Tomato fruit mitochondria also showed a dependence on adenine nucleotide in the presence of DNP and succinate and the absence of hexokinase (5). Heytler (7) reported a graduated suppression of oxygen uptake with increasing concentrations of the uncoupler, in-Cl-carbonyl cyanide phenylhydrazone, in the presence of hexokinase, in mouse liver mitochondria oxidizing succinate. Inhibition of succinate oxidation in rat liver and potato mitochondria in the absence of hexokinase depended on the concentration of uncoupler -(12, 13). The inhibition of succinate oxidation may be due to an inhibition of succinate dehyodrogenase (EC 1.3.99.1) by oxaloacetate (13). Wiskich and Bonner (13) suggested that ATP, which could be formed