Off-pump coronary artery bypass grafting for patients with severely reduced ventricular function-A justified strategy?

BACKGROUND AND AIM: Low ejection fraction (EF) has been identified as a main risk factor for perioperative complications and mortality after coronary artery bypass grafting (CABG). The purpose of this study was to compare the efficacy and early as well as midterm outcomes of off-pump CABG (OPCAB) and conventional CABG (ONCAB) surgery in patients with reduced EF. METHODS: We performed a retrospective review of patient demographics, preoperative risk factors, operative and postoperative outcomes of patients with left ventricular EF (LV-EF) ≤35%, who underwent CABG at our institution between January 2015 and December 2017. Propensity score and multivariate logistic regression analysis were used to compare risk adjusted outcomes between groups. RESULTS: Overall, 111 consecutive CABG-patients with LV-EF ≤ 35% underwent either ONCAB (46 patients, 41.4%) or OPCAB surgery (65 patients, 58.6%). There was no difference in early mortality (5% vs. 7.5%, p = .64) between groups. After propensity score matching, OPCAB-patients required significantly less re-sternotomies for bleeding (20% vs. 2.5%, p = .03) and consequently received significantly less blood transfusions (57.5% vs. 32.5%, p = .03). Fewer OPCAB-patients experienced low cardiac output syndrome (22.5% vs. 42.5%, p = .06) and suffered from postoperative delirium (22.5% vs. 42.5%, p = .06). There were no differences in completeness of revascularization between groups (median 1 (1.0-1.33; 1.0-1.33) OPCAB versus median 1 (1-1.33; 0.67-2) ONCAB, p = .95). Survival after 6 months, one year and three years was similar for ONCAB- and OPCAB-patients (ONCAB 92.3%, 89.4%, and 89.4% vs. OPCAB 89.8%, 85.7%, and 82.1%; p = .403). More ONCAB-patients needed a coronary re-intervention during follow-up (8.6% vs. 2.3%, p = .402). CONCLUSION: OPCAB-surgery is a safe and effective option for patients with reduced EF. Furthermore, it does not come at the expense of less complete revascularization or increased coronary re-intervention during early follow-up.

Impact of Whole-Body Perfusion in Postoperative Outcomes After Aortic Arch Reconstruction Surgery in Neonates and Infants.

INTRODUCTION: The aim of this study was to determine whether whole-body perfusion (WBP) consisting of a combined antegrade cerebral perfusion (ACP) and lower body perfusion (LBP) improves the outcome after aortic arch reconstruction surgery in neonates compared with ACP. METHODS: Sixty-five consecutive patients under one year of age who underwent aortic arch reconstruction as the main procedure or as part of a more complex surgery from 2014-2020 in our center were included. The patients were separated into two groups, according to the perfusion strategy, either ACP (34 patients) as the control group or WBP (31 patients) as the intervention group. LBP was achieved through an arterial sheath in the femoral artery. Outcome parameters were postoperative renal, gastrointestinal, and neurological complications and 30-day mortality. RESULTS: The patients in the WBP group showed lower intraoperative lactate levels and close to normal early postoperative renal and hepatic enzymes and LDH at PICU admission compared with the patients in the ACP group. The number of patients suffering from postoperative neurological complications and multiorgan failure was lower in the WBP group. CONCLUSION: In our experience, the combined use of ACP and LBP through the femoral artery showed an improvement, regarding postoperative neurologic complications in neonates and infants undergoing aortic arch surgery.

The impact of 3D printed models on spatial orientation in echocardiography teaching.

PURPOSE: During our transthoracic echocardiography (TTE) courses, medical students showed difficulty in spatial orientation. We implemented the use of 3D printed cardiac models of standard TTE views PLAX, PSAX, and A4C and assessed their efficacy in TTE-teaching. METHODS: One hundred fifty-three participants were split into two groups. A pre-test-retest of anatomy, 2D -, and 3D orientation was conducted. The intervention group (n = 77) was taught using 3D models; the control group (n = 76) without. Both were comparable with respect to baseline parameters. Besides test-scores, a Likert scale recorded experiences, difficulties, and evaluation of teaching instruments. RESULTS: From the 153 students evaluated, 123 improved, 20 did worse, and ten achieved the same result after the course. The median overall pre-test score was 29 of 41 points, and the retest score was 35 (p < 0.001). However, the intervention group taught with the 3D models, scored significantly better overall (p = 0.016), and in 2D-thinking (p = 0.002) and visual thinking (p = 0.006) subtests. A backward multivariate linear regression model revealed that the 3D models are a strong individual predictor of an excellent visual thinking score. In addition, our study showed that students with difficulty in visual thinking benefited considerably from the 3D models. CONCLUSION: Students taught using the 3D models significantly improved when compared with conventional teaching. Students regarded the provided models as most helpful in their learning process. We advocate the implementation of 3D-printed heart models featuring the standard views for teaching echocardiography. These findings may be transferable to other evidence based medical and surgical teaching interventions.

Site-Specific Conjugation Strategy for Dual Antibody-Drug Conjugates Using Aerobic Formylglycine-Generating Enzymes.

Multiple, site-specific protein conjugation is increasingly attractive for the generation of antibody-drug conjugates (ADCs). As it is important to control the number and position of cargoes in an ADC, position-selective generation of reactive sites in the protein of interest is required. Formylglycine (FGly) residues are generated by enzymatic conversion of cysteine residues embedded in a certain amino acid sequence motif with a formylglycine-generating enzyme (FGE). The addition of copper ions increases FGE activity leading to the conversion of cysteines within less readily accepted sequences. With this tuned enzyme activity, it is possible to address two different recognition sequences using two aerobic formylglycine-generating enzymes. We demonstrate an improved and facile strategy for the functionalization of a DARPin (designed ankyrin repeat protein) and the single-chain antibody scFv425-Fc, both directed against the epidermal growth factor receptor (EGFR). The single-chain antibody was conjugated with monomethyl auristatin E (MMAE) and carboxyfluorescein (CF) and successfully tested for receptor binding, internalization, and cytotoxicity in cell culture, respectively.

Bifunctional Reagents for Formylglycine Conjugation: Pitfalls and Breakthroughs.

Formylglycine-generating enzymes specifically oxidize cysteine within the consensus sequence CxPxR to Cα -formylglycine (FGly). This noncanonical electrophilic amino acid can subsequently be addressed selectively by bioorthogonal hydrazino-iso-Pictet-Spengler (HIPS) or Knoevenagel ligation to attach payloads like fluorophores or drugs to proteins to obtain a defined payload-to-protein ratio. However, the disadvantages of these conjugation techniques include the need for a large excess of conjugation building block, comparably low reaction rates and limited stability of FGly-containing proteins. Therefore, functionalized clickable HIPS and tandem Knoevenagel building blocks were synthesized, conjugated to small proteins (DARPins) and subsequently linked to strained alkyne-containing payloads for protein labeling. This procedure allowed the selective bioconjugation of one or two DBCO-carrying payloads with nearly stoichiometric amounts at low concentrations. Furthermore, an azide-modified tandem Knoevenagel building block enabled the synthesis of branched PEG linkers and the conjugation of two fluorophores, resulting in an improved signal-to-noise ratio in live-cell fluorescence-imaging experiments targeting the EGF receptor.

Off-Pump Coronary Artery Bypass Grafting in Acute Coronary Syndrome: Focus on Safety and Completeness of Revascularization.

BACKGROUND: Emergency coronary artery bypass grafting (CABG) in the setting of acute coronary syndrome (ACS) has been associated with increased morbidity and mortality. Avoiding cardiopulmonary bypass might be advantageous, but the role of off-pump CABG (OPCAB) remains controversial, as it has been associated with incomplete revascularization in several studies. The objective of this study was to evaluate the feasibility, efficacy, and outcome of OPCAB surgery in ACS patients. METHODS: We performed a retrospective review of ACS patients who underwent on-pump CABG (ONCAB) or OPCAB, either emergently or delayed, at our institution. RESULTS: Between January 2015 and December 2016, a total of 205 consecutive ACS patients underwent either ONCAB (109 patients, 53.2%) or OPCAB surgery (96 patients, 46.8%). EuroSCORE II levels (5.6 ± 7.2 vs 4.9 ± 6.5, p = 0.226) and demography were comparable between groups.A trend towards lower postoperative mortality was observed in OPCAB patients (2.1 vs 5.5%). The incidence of postoperative stroke and low cardiac output syndrome, as well as the duration of inotropic support and the need for re-sternotomy, was significantly lower in the OPCAB group (p < 0.05).CABG performed instantly in an emergency situation was not associated with increased mortality or morbidity when compared with delayed procedures, and OPCAB surgery in emergency patients was associated with lower postoperative morbidity and shorter stays in the intensive care unit (p < 0.05).There were no differences in completeness of revascularization between groups (median 1 [1-1.33;0.33-1.67] OPCAB versus median 1 (1-1.33;0.67-2) ONCAB, p = 0.617), even in the emergency setting. CONCLUSION: OPCAB surgery is safe and effective in ACS and may be considered in hemodynamically stable patients in the emergency setting.

Video assisted thoracoscopic sympathectomy for intractable recurrent VT after minimal-invasive LVAD implantation.

BACKGROUND: Recurrent ventricular tachycardia (VT) can occur after left ventricular assist device (LVAD) implantation. In this case, medical treatment might be insufficient. We report a case of a left-sided thoracoscopic sympathectomy as a feasible treatment escalation in intractable VT. CASE REPORT: A 72-year-old patient underwent an internal cardioverter defibrillator (ICD) implantation as primary prophylaxis for VTs in the setting of staged heart failure therapy. Afterwards, due to a progressive dilative cardiomyopathy he underwent a minimal-invasive LVAD implantation (HeartWare, Medtronic). After an uneventful minimal-invasive LVAD-implantation the patient was discharged to a rehabilitation program. However, after 7 weeks he developed recurrent VTs which were successfully terminated by ICD shocks deliveries leading to severe discomfort and frequent hospitalizations. Eventually, the patient was admitted with an electrical VT storm. Successful endocardial catheter ablation of all inducible VTs were performed combined with multiple rearrangements of his oral antiarrhythmic medication. However, all these treatments could not suppress further occurrence of VTs. After an interdisciplinary discussion the patient agreed to a left-sided video-assisted thoracoscopic sympathectomy. After a follow up of 150 days the patient was free from VTs apart from one short event. CONCLUSION: We believe video-assisted thoracoscopic sympathectomy might be a surgical treatment option in patients with intractable recurrent VTs after catheter ablation of VT reentrant substrate even after minimal-invasive LVAD implantation.

Conversion of Serine-Type Aldehyde Tags by the Radical SAM Protein AtsB from Methanosarcina mazei.

Formylglycine-generating enzymes provide a convenient tool for site-specific protein derivatization. Their ability to oxidize cysteine or serine residues within a defined consensus sequence to Cα -formylglycine (FGly) allows for the targeted introduction of a unique chemical handle for various bioconjugation reactions. In recent years, oxygen-dependent FGly-generating enzyme saw broad use in protein functionalization and the generation of protein conjugates. Yet, the FGly-generating system AtsB, along with its capability to convert unusual aldehyde tag sequences, remains mostly unused. Herein, the ability of AtsB from Methanosarcina mazei to convert nonclassical aldehyde tags of the SX(A/P)XR-type and its potential use in bioconjugation chemistry are demonstrated.

Formylglycine-generating enzymes for site-specific bioconjugation.

Site-specific bioconjugation strategies offer many possibilities for directed protein modifications. Among the various enzyme-based conjugation protocols, formylglycine-generating enzymes allow to posttranslationally introduce the amino acid Cα-formylglycine (FGly) into recombinant proteins, starting from cysteine or serine residues within distinct consensus motifs. The aldehyde-bearing FGly-residue displays orthogonal reactivity to all other natural amino acids and can, therefore, be used for site-specific labeling reactions on protein scaffolds. In this review, the state of research on catalytic mechanisms and consensus motifs of different formylglycine-generating enzymes, as well as labeling strategies and applications of FGly-based bioconjugations are presented.

Expression, characterization, and site-specific covalent immobilization of an L-amino acid oxidase from the fungus Hebeloma cylindrosporum.

L-Amino acid oxidases (LAAOs) are flavoproteins, which use oxygen to deaminate L-amino acids and produce the corresponding α-keto acids, ammonia, and hydrogen peroxide. Here we describe the heterologous expression of LAAO4 from the fungus Hebeloma cylindrosporum without signal sequence as fusion protein with a 6His tag in Escherichia coli and its purification. 6His-hcLAAO4 could be activated by exposure to acidic pH, the detergent sodium dodecyl sulfate, or freezing. The enzyme converted 14 proteinogenic L-amino acids with L-glutamine, L-leucine, L-methionine, L-phenylalanine, L-tyrosine, and L-lysine being the best substrates. Methyl esters of these L-amino acids were also accepted. Even ethyl esters were converted but with lower activity. Km values were below 1 mM and vmax values between 19 and 39 U mg-1 for the best substrates with the acid-activated enzyme. The information for an N-terminal aldehyde tag was added to the coding sequence. Co-expressed formylglycine-generating enzyme was used to convert a cysteine residue in the aldehyde tag to a Cα-formylglycine residue. The aldehyde tag did not change the properties of the enzyme. Purified Ald-6His-hcLAAO4 was covalently bound to a hexylamine resin via the Cα-formylglycine residue. The immobilized enzyme could be reused repeatedly to generate phenylpyruvate from L-phenylalanine with a total turnover number of 17,600 and was stable for over 40 days at 25 °C.

Cardiac surgery in the presence of chronic internal carotid artery occlusion.

The aim was to evaluate the incidence of stroke in the setting of cardiac surgery with or without hemodynamically relevant asymptomatic carotid stenosis contralateral to the occlusion. We designed a historical cohorts study, focused on patients with unilateral totally occluded internal carotid arteries who were referred for any cardiac surgery at our center. Isolated unilateral occlusions were assigned to group 1 (n = 60), and those with a contralateral stenosis grade ≥ 60% were included in group 2 (n = 51). A total of 111 patients operated in our center from 1997 to 2016 were included. Patients in group 2 had an asymptomatic contralateral internal carotid artery stenosis with a mean stenosis grade of 71 ± 20%. Simultaneous carotid endarterectomy (CEA) was performed in 22 patients from group 2. The overall mortality was 8/111 (7.2%). Carotid-associated mortality was not observed, whereas an overall stroke incidence of 8/111 (7.2%) was detected. The group-related outcome showed comparable results for mortality (group 1: 4/60 (6.7%) vs. group 2: 4/51 (7.8%); p = 1.0). Regarding stroke incidence, group 2 had a higher incidence of overall strokes (2/60 (3.3%) vs. 6/51 (11.8%); p = 0.14) with more contralateral (0/60 (0%) vs. 2/51 (3.9%); p = 0.209) and ipsilateral strokes (2/60 (3.3%) vs. 4/51 (7.8%); p = 0.411). Stroke rate peaked in patients with simultaneous carotid and cardiac surgery (n = 22; 18.2%; p = 0.048). Performing simultaneous CEA during cardiac surgery in the presence of a contralateral occlusion may promote stroke. Asymptomatic contralateral carotid stenosis is a risk factor for stroke in patients with carotid occlusion prior to cardiac surgery.

Hybrid Off-pump Second-Stage Aortic Arch Repair after Type A Dissection.

BACKGROUND: Ascending aorta or hemi-arch repair are common in the acute phase of type A dissection. Postdissection aneurysms can develop with antegrade perfusion of the false lumen in the dissected aortic arch and require reoperation. METHODS: From 2012 to 2018, we reoperated nine patients with postdissection aneurysms using a hybrid technique without cardiopulmonary bypass. The patients had a EuroSCORE II of 13% and a logistic EuroSCORE I of 45% and were not candidates for frozen elephant trunk surgery. The median interval since the acute ascending repair was 184 (92; 528) days. All patients were treated by median resternotomy, ascending to carotid bypass on a partially clamped ascending graft, and transfemoral endovascular repair with a Relay NBS (nonbare stent) or conformable Gore C-TAG stent graft. RESULTS: Technical success was achieved in all cases. Mean follow-up was 405 (220; 672) days. There was no disabling stroke, endoleak, paraplegia, in-hospital, or late mortality. In all patients, the false lumen was completely thrombosed at the aortic arch level with a median aneurysm shrinkage of 13 mm in the distal arch. There was no bird beak or stent graft migration. Distal stent-induced new entry was observed in one case. Reinterventions were not necessary due to diameter stability. CONCLUSION: Complete debranching with transfemoral thoracic endovascular aneurysm repair showed encouraging results in patients with relevant comorbidities. The used stent grafts performed well in the mid-term follow-up period with no endoleaks or migration.

Two-fold Bioorthogonal Derivatization by Different Formylglycine-Generating Enzymes.

Formylglycine-generating enzymes are of increasing interest in the field of bioconjugation chemistry. They catalyze the site-specific oxidation of a cysteine residue to the aldehyde-containing amino acid Cα -formylglycine (FGly). This non-canonical residue can be generated within any desired target protein and can subsequently be used for bioorthogonal conjugation reactions. The prototypic formylglycine-generating enzyme (FGE) and the iron-sulfur protein AtsB display slight variations in their recognition sequences. We designed specific tags in peptides and proteins that were selectively converted by the different enzymes. Combination of the different tag motifs within a single peptide or recombinant protein enabled the independent and consecutive introduction of two formylglycine residues and the generation of heterobifunctionalized protein conjugates.

NMR spectroscopic conformational analysis of 4-methylene-cyclohexyl pivalate-The effect of sp2 hybridization.

The conformational equilibrium of the axial/equatorial conformers of 4-methylene-cyclohexyl pivalate is studied by dynamic NMR spectroscopy in a methylene chloride/freon mixture. At 153 K, the ring interconversion gets slow on the nuclear magnetic resonance timescale, the conformational equilibrium (-ΔG°) can be examined, and the barrier to ring interconversion (ΔG# ) can be determined. The structural influence of sp2 hybridization on both ΔG° and ΔG# of the cyclohexyl moiety can be quantified.

Impella 5.0 as a Second-Line Mechanical Circulatory Support Strategy After Extracorporeal Life Support.

The catheter-based Impella 5.0 left ventricular assist device is a powerful and less invasive alternative for patients in cardiogenic shock. The use as second-line therapy in patients with precedent extracorporeal life support (ECLS) has not been described before now. We analyzed our experience of consecutive patients treated with this alternative strategy. From April 2014 to December 2014, eight patients had been implanted as a second-line option after ECLS support. The reason for the change from ECLS to Impella 5.0 was absence of cardiac recovery for primary weaning and complications of ECLS therapy. The mean time of ECLS support prior to Impella implantation was 12 ± 7 days. The implantation of the Impella 5.0/CP was technically successful in all patients, and the ECLS could be explanted in all eight patients who received Impella implantation as a second-line treatment. The second-line Impella 5.0 therapy resulted in two patients who turned into left ventricular assist device (LVAD) candidates, two primary weaning candidates, and four patients who died in the setting of sepsis or absent cardiac recovery and contraindications for durable LVAD therapy. Thereby, the overall hospital discharge survival as well as the 180-day survival was 50% for Impella 5.0 implantations as second-line procedure after ECLS. The latest follow-up survival of this second-line strategy after ECLS was three out of eight, as one patient died after 299 days of LVAD support due to sepsis. The use of Impella 5.0 constitutes a possible second-line therapeutic option for those patients who do not show cardiac recovery during prolonged ECLS support or suffer from complications of ECLS therapy. This treatment allows additional time for decisions regarding cardiac recovery or indication for durable LVAD therapy.

A density explanation of valence asymmetries in recognition memory.

The density hypothesis states that positive information is more similar than negative information, resulting in higher density of positive information in mental representations. The present research applies the density hypothesis to recognition memory to explain apparent valence asymmetries in recognition memory, namely, a recognition advantage for negative information. Previous research explained this negativity advantage on the basis of valence-induced affect. We predicted that positive information's higher density impairs recognition performance. Two old-new word recognition experiments tested whether differential density between positive and negative stimuli creates a negativity advantage in recognition memory, over and above valence-induced affect. In Experiment 1, participants better discriminated negative word stimuli (i.e., less false alarms) and showed a response bias towards positive words. Regression analyses showed the asymmetry to be function of density and not of valence. Experiment 2 varied stimulus density orthogonal to valence. Again, discriminability and response bias were a function of density and not of valence. We conclude that the higher density of positive information causes an apparent valence asymmetry in recognition memory.

Surgery on extracorporeal circulation in early and advanced non-small cell lung cancer.

BACKGROUND: Locally advanced (T4) non-small cell lung cancer (NSCLC) is principally amenable to surgery. For radical resection of cardiovascular structures, extracorporeal circulation (ECC) may be required. Tumor dissemination is a concern in this situation. In this study, we evaluate the long-term results of T4 NSCLC surgery with ECC and compare them with combined cardiopulmonary surgery for early-stage NSCLC and heart disease. METHODS: We retrospectively analyzed 16 patients undergoing surgery on ECC over a 13-year period. Eight patients suffered from T4 NSCLC (group A), and another eight patients suffered from coincidental T1-T2 NSCLC and heart disease (group B). RESULTS: In group A, five patients received neoadjuvant radiochemotherapy. Complete resection was achieved in all patients. Thirty-day mortality was one patient (12.5%) in each group. Six patients died from recurrent cancer with a median survival of 13.6 months in group A. Prognosis in patients with direct tumor invasion of the aortopulmonary window was a lot worse compared to those with atrial infiltration. One T4 patient who had only received surgery survived for 155 months without relapse. In group B, no NSCLC relapse occurred, and median survival was 21.6 months. All but one death in group B occurred due to cardiovascular incidents. CONCLUSIONS: Surgery on ECC for T4 NSCLC gives satisfactory results. The site of infiltration appears to be most important for local tumor relapse. Long-term survival is possible in some cases. Simultaneous cardiac and pulmonary surgery resulted in good early and midterm outcomes without surgery-induced tumor propagation.

Early outcomes of patients with Marfan syndrome and acute aortic type A dissection.

BACKGROUND: Acute aortic Stanford type A dissection remains a frequent and life-limiting event for patients with Marfan syndrome. Outcome results in this high-risk group are limited. METHODS: The German Registry for Acute Aortic Dissection Type A collected the data of 56 centers between July 2006 and June 2015. Of 3385 patients undergoing operations for acute aortic Stanford type A dissection, 117 (3.5%) were diagnosed with Marfan syndrome. We performed a propensity score match comparing patients with Marfan syndrome with patients without Marfan syndrome in a 1:2 fashion. RESULTS: Patients with Marfan syndrome were significantly younger (42.9 vs 62.2 years; P < .001), predominantly male (76.9% vs 62.9%; P = .002), and less catecholamine dependent (9.4% vs 20.3%; P = .002) compared with the unmatched cohort. They presented with aortic regurgitation (41.6% vs 23.0%; P < .001) and involvement of the supra-aortic vessels (50.4% vs 39.5%; P = .017) more often. Propensity matching revealed 82 patients with Marfan syndrome (21 female) with no significant differences in baseline characteristics compared with patients without Marfan syndrome (n = 159, 36 female; P = .607). Although root preservation was more frequent in patients with Marfan syndrome, procedure types did not differ significantly (18.3% vs 10.7%; P = .256). Aortic arch surgery was performed more frequently in matched patients (87.5% vs 97.8%; P = .014). Thirty-day mortality did not differ between patients with and without Marfan syndrome (19.5% vs 20.1%; P = .910). Multivariate regression showed no influence of Marfan syndrome on 30-day mortality (odds ratio, 0.928; 95% confidence interval, 0.346-2.332; P = .876). CONCLUSIONS: Marfan syndrome does not adversely affect 30-day outcomes after surgical repair for acute aortic Stanford type A dissection compared with a matched cohort. Long-term outcome analysis is needed to account for the influence of further downstream interventions.

Cerebral protection during surgery for acute aortic dissection type A: results of the German Registry for Acute Aortic Dissection Type A (GERAADA).

BACKGROUND: Cerebral protection during surgery for acute aortic dissection type A relies on hypothermic circulatory arrest, either alone or in conjunction with cerebral perfusion. METHODS AND RESULTS: The perioperative and intraoperative conditions of 1558 patients submitted from 44 cardiac surgery centers in German-speaking countries were analyzed. Among patients with acute aortic dissection type A, 355 (22.8%) underwent surgery with hypothermic circulatory arrest alone. In 1115 patients (71.6%), cerebral perfusion was used: Unilateral antegrade cerebral perfusion (ACP) in 628 (40.3%), bilateral ACP in 453 (29.1%), and retrograde perfusion in 34 patients (2.2%). For 88 patients with acute aortic dissection type A (5.6%), no circulatory arrest and arch intervention were reported (cardiopulmonary bypass-only group). End points of the study were 30-day mortality (15.9% overall) and mortality-corrected permanent neurological dysfunction (10.5% overall). The respective values for the cardiopulmonary bypass-only group were 11.4% and 9.1%. Hypothermic circulatory arrest alone resulted in a 30-day mortality rate of 19.4% and a mortality-corrected permanent neurological dysfunction rate of 11.5%, whereas the rates were 13.9% and 10.0%, respectively, for unilateral ACP and 15.9% and 11.0%, respectively, for bilateral ACP. In contrast with the ACP groups, there was a profound increase in mortality when systemic circulatory arrest times exceeded 30 minutes in the hypothermic circulatory arrest group (P<0.001). Mortality-corrected permanent neurological dysfunction correlated significantly with perfusion pressure in the ACP groups. CONCLUSIONS: This study reflects current surgical practice for acute aortic dissection type A in Central Europe. For arrest times less than 30 minutes, hypothermic circulatory arrest and ACP lead to similar results. For longer arrest periods, ACP with sufficient pressure is advisable. Outcomes with unilateral and bilateral ACP were equivalent.

Treatment of the aortic root in acute aortic dissection type A: insights from the German Registry for Acute Aortic Dissection Type A.

OBJECTIVES: Surgery of the aortic root in acute aortic dissection type A (AADA) remains a topic of vague evidence since the extend of dissection and surgeons' capability and interpretation of the disease vary remarkably. We aimed to interpret root operation strategies in the German Registry for Acute Aortic Dissection cohort. METHODS: German Registry for Acute Aortic Dissection collected the data of 56 centres between July 2006 and June 2015. A total of 3382 patients undergoing operations for AADA were included and divided into 3 groups according to aortic root procedure types: supracommissural replacement (SCR), conduit replacement (CR) and valve sparing root replacement (VSRR). RESULTS: Patients in SCR (2425, 71.7%) were significantly older than CR (681, 20.1%) and VSRR (276, 8.2%) (63.4 vs 57.5 vs 54.2 years; P < 0.001), more female (38.9% vs 32.0% vs 26.1%; P < 0.001) and presented with less aortic regurgitation (26.3% vs 57.1% vs 56.5%; P < 0.001). VSRR presented with slightly less multiple organ malperfusion (11.6% vs 12.0% vs 10.9%; P = 0.045) and were more often diagnosed for Marfan syndrome (2.4% vs 5.1% vs 9.1%; P < 0.001). Thirty-day mortality was lower for VSRR (11.6%) compared to SCR (16.1%) and CR (19.8%; P = 0.010). Despite longer procedural times, multivariable regression showed no influence of total arch replacement for VSRR on mortality compared to CR (odds ratio 0.264; 95% confidence interval, 0.033-2.117; P = 0.21). CONCLUSIONS: SCR remains the procedure of choice in elderly and compromised patients. Extended root preservation techniques may be applied even in combination with extended aortic arch surgery for selected patients for AADA with promising early outcomes.