Perfusion quality odds (PEQUOD) trial: validation of the multifactorial dynamic perfusion index as a predictor of cardiac surgery-associated acute kidney injury

OBJECTIVES

The multifactorial dynamic perfusion index was recently introduced as a predictor of cardiac surgery-associated acute kidney injury. The multifactorial dynamic perfusion index was developed based on retrospective data retrieved from the patient files. The present study aims to prospectively validate this index in an external series of patients, through an on-line measure of its various components.

METHODS

inclusion criteria were: adult patients undergoing cardiac surgery with cardiopulmonary bypass. Data collection included preoperative factors, and cardiopulmonary bypass-related factors. These were collected on-line using a dedicated monitor. Factors composing the multifactorial dynamic perfusion index are the nadir hematocrit, the nadir oxygen delivery, the time of exposure to a low oxygen delivery, the nadir mean arterial pressure, cardiopulmonary bypass duration, the use of red blood cell transfusions, and the peak arterial lactates.

RESULTS

200 hundred adult patients were investigated The multifactorial dynamic perfusion index had a good (c-statistics 0.81) discrimination for cardiac surgery-associated acute kidney injury (any stage) and an excellent (c-statistics 0.93) discrimination for severe patterns (stage 2-3). Calibration was modest for cardiac surgery-associated acute kidney injury (any stage) and good for stage 2-3. The use of vasoconstrictors was an additional factor associated with cardiac surgery-associated acute kidney injury.

CONCLUSIONS

The multifactorial dynamic perfusion index is validated for discrimination of cardiac surgery-associated acute kidney injury risk. It incorporates modifiable risk factors, and may help in reducing the occurrence of cardiac surgery-associated acute kidney injury.

Neurocognitive function in procedures correcting severe aortic valve stenosis: patterns and determinants

Background

Neurocognitive changes occurring after a surgical aortic valve replacement (SAVR) or transcatheter aortic valve implantation (TAVI) procedure for the correction of severe aortic stenosis (AS) have not been widely addressed and, if addressed, have produced conflicting results. The purpose of this study is to identify the pre-procedural neurocognitive pattern and its determinants in a setting of elderly (>65 years) patients with severe AS undergoing SAVR or TAVI and the changes occurring at a 2-3 month follow-up.

Methods

This was a prospective cohort study included in the Italian Registry on Outcomes in Aortic Stenosis Treatment in Elderly Patients. Patients were assessed both before and after (2-3 months) the procedure using the Montreal Cognitive Assessment (MoCA) test. Data on periprocedural demographics, clinical factors, and outcome measures were collected.

Results

Before the procedure, 70% of the patients demonstrated a MoCA score <23 points, which was indicative of cognitive dysfunction. The factors associated with neurocognitive dysfunction were age, functional capacity, chronic heart failure, and hemoglobin levels. After the procedure, there was an overall improvement in the MoCA score of the patients, but 28% of the patients showed a reliable worsening of their condition. The factors associated with MoCA worsening were platelet transfusions and the amount of red blood cell units transfused.

Conclusion

The correction of severe AS leads to an improvement in neurocognitive function after 2-3 months. This improvement does not differentiate between SAVR and TAVI after matching for pre-procedural factors. The only modifiable factor associated with pre-procedural neurocognitive function is anemia, and anemia correction with red blood cell transfusions is associated with a worsening of neurocognitive function. This leads to the hypothesis that anemia correction before the procedure (with iron and/or erythropoietin) may limit the risk of a post-procedural worsening of neurocognitive function.

Finding a common definition of heparin resistance in adult cardiac surgery: communication from the ISTH SSC subcommittee on perioperative and critical care thrombosis and hemostasis

Ensuring adequate anticoagulation for patients requiring cardiac surgery and cardiopulmonary bypass (CPB) is important due to the adverse consequences of inadequate anticoagulation with respect to bleeding and thrombosis. When target anticoagulation is not achieved with typical doses, the term heparin resistance is routinely used despite the lack of uniform diagnostic criteria. Prior reports and guidance documents that define heparin resistance in patients requiring CPB and guidance documents remain variable based on the lack of standardized criteria. As a result, we conducted a review of clinical trials and reports to evaluate the various heparin resistance definitions employed in this clinical setting and to identify potential standards for future clinical trials and clinical management. In addition, we also aimed to characterize the differences in the reported incidence of heparin resistance in the adult cardiac surgical literature based on the variability of both target-activated clotting (ACT) values and unfractionated heparin doses. Our findings suggest that the most extensively reported ACT target for CPB is 480 seconds or higher. Although most publications define heparin resistance as a failure to achieve this target after a weight-based dose of either 400 U/kg or 500 U/kg of heparin, a standardized definition would be useful to guide future clinical trials and help improve clinical management. We propose the inability to obtain an ACT target for CPB of 480 seconds or more after 500 U/kg as a standardized definition for heparin resistance in this setting.

Long-term survival after surgical treatment for post-infarction mechanical complications: results from the Caution study

BACKGROUND AND AIMS

Mechanical complications (MCs) are rare but potentially fatal sequelae of acute myocardial infarction (AMI). Surgery, though challenging, is considered the treatment of choice. The authors sought to study early and long-term results of patients undergoing surgical treatment for post-AMI MCs.

METHODS

Patients undergone surgical treatment for post-infarction MCs between 2001 through 2019 in 27 centers worldwide were retrieved from the database of CAUTION study. In-hospital and long-term mortality were the primary outcomes. Cox proportional hazards regression models were used to determine independent factors associated with overall mortality.

RESULTS

The study included 720 patients. The median age was 70.0 [62.0-77.0] years, with a male predominance (64.6%). The most common MC encountered was ventricular septal rupture (VSR) (59.4%). Cardiogenic shock was seen on presentation in 56.1% of patients. In-hospital mortality rate was 37.4%; in more than 50% of cases, the cause of death was low cardiac output syndrome (LCOS). Late mortality occurred in 133 patients, with a median follow-up of 4.4 [1.0-8.6] years. Overall survival at 1, 5 and 10 years was 54.0%, 48.1% and 41.0%, respectively. Older age (p < 0.001) and postoperative LCOS (p < 0.001) were independent predictors of overall mortality. For hospital survivors, 10-year survival was 65.7% and was significant higher for patients with VSR than those with papillary muscle rupture (long-rank P = 0.022).

CONCLUSIONS

Contemporary data from a multicenter cohort study show that surgical treatment for post-AMI MCs continues to be associated with high in-hospital mortality rates. However, long-term survival in patients surviving the immediate postoperative period is encouraging.Trial registration number: NCT03848429.

The multifactorial dynamic perfusion index: A predictive tool of cardiac surgery associated acute kidney injury

INTRODUCTION

cardiac surgery associated acute kidney injury (CSA-AKI) has a number of preoperative and intraoperative risk factors. Cardiopulmonary bypass (CPB) factors have not yet been elucidated in a single multivariate model. The aim of this study is to develop a dynamic predictive model for CSA-AKI.

METHODS

retrospective study on 910 consecutive adult cardiac surgery patients. Baseline data were used to settle a preoperative CSA-AKI risk model (static risk model, SRM); CPB related data were assessed for association with CSA-AKI. CPB duration, nadir oxygen delivery, time of exposure to a low oxygen delivery, nadir mean arterial pressure, peak lactates and red blood cell transfusion were included in a multivariate dynamic perfusion risk (DPR). SRM and DPR were merged into a final logistic regression model (multifactorial dynamic perfusion index, MDPI). The three risk models were assessed for discrimination and calibration.

RESULTS

the SRM model had an AUC of 0.696 (95% CI 0.663-0.727), the DPR model of 0.723 (95% CI 0.691-0.753), and the MDPI model an AUC of 0.769 (95% CI 0.739-0.798). The difference in AUC between SRM and DPR was not significant (p = 0.495) whereas the AUC of MDPI was significantly larger than that of SRM (p = 0.004) and DPR (p = 0.015).

CONCLUSIONS

inclusion of dynamic indices of the quality of CPB improves the discrimination and calibration of the preoperative risk scores. The MDPI has better predictive ability than the existing static risk models and is a promising tool to integrate different factors into an advanced concept of goal-directed perfusion.

Impact of COVID-19 on incidence and outcomes of post-infarction mechanical complications in Europe

OBJECTIVES

Post-acute myocardial infarction mechanical complications (post-AMI MCs) represent rare but life-threatening conditions, including free-wall rupture, ventricular septal rupture and papillary muscle rupture. During the coronavirus disease-19 (COVID-19) pandemic, an overwhelming pressure on healthcare systems led to delayed and potentially suboptimal treatments for time-dependent conditions. As AMI-related hospitalizations decreased, limited information is available whether higher rates of post-AMI MCs and related deaths occurred in this setting. This study was aimed to assess how COVID-19 in Europe has impacted the incidence, treatment and outcome of MCs.

METHODS

The CAUTION-COVID19 study is a multicentre retrospective study collecting 175 patients with post-AMI MCs in 18 centres from 6 European countries, aimed to compare the incidence of such events, related patients' characteristics, and outcomes, between the first year of pandemic and the 2 previous years.

RESULTS

A non-significant increase in MCs was observed [odds ratio (OR) = 1.15, 95% confidence interval (CI) 0.85-1.57; P = 0.364], with stronger growth in ventricular septal rupture diagnoses (OR = 1.43, 95% CI 0.95-2.18; P = 0.090). No significant differences in treatment types and mortality were found between the 2 periods. In-hospital mortality was 50.9% and was higher for conservatively managed cases (90.9%) and lower for surgical patients (44.0%). Patients admitted during COVID-19 more frequently had late-presenting infarction (OR = 2.47, 95% CI 1.24-4.92; P = 0.010), more stable conditions (OR = 2.61, 95% CI 1.27-5.35; P = 0.009) and higher EuroSCORE II (OR = 1.04, 95% CI 1.01-1.06; P = 0.006).

CONCLUSIONS

A non-significant increase in MCs incidence occurred during the first year of COVID-19, characterized by a significantly higher rate of late-presenting infarction, stable conditions and EuroSCORE-II if compared to pre-pandemic data, without affecting treatment and mortality.

Incidence and predictors of 30-day and 6-month stroke after TAVR: Insights from the multicenter OBSERVANT II study

BACKGROUND

The incidence and predictors of 30-day stroke after transcatheter aortic valve replacement (TAVR) were derived from early studies investigating first-generation devices. The incidence of 6-month stroke and its related predictors are unknown.

AIMS

To investigate the incidence and to identify procedural and patient-related predictors of 30-day and 6-month stroke after TAVR.

METHODS

Data from 2753 consecutive patients with severe aortic stenosis undergoing TAVR were obtained from the OBSERVANT-II study, an observational, prospective, multicenter cohort study. The study endpoints were symptomatic 30-day and 6-month stroke after TAVR.

RESULTS

The occurrence of a 30-day and 6-month stroke was low (1.3% and 2.4%, respectively) but with significant impact on survival. Aortic valve predilatation (odds ratio [OR]: 2.28, 95% confidence interval [CI]: 1.12-4.65, p = 0.023), diabetes (OR: 3.10, 95% CI: 1.56-6.18, p = 0.001), and left ventricle ejection fraction < 50% (OR: 2.15, 95% CI: 1.04-4.47, p = 0.04) were independent predictors of 30-day stroke, whereas diabetes (sub-distribution hazard ratio [SHR]: 2.07, 95% CI: 1.25-3.42, p = 0.004), pre-existing neurological dysfunction (SHR: 3.92, 95% CI: 1.54-10, p = 0.004), bicuspid valve (SHR: 4.75, 95% CI: 1.44-15.7, p = 0.011), and critical status (SHR: 3.05, 95% CI: 1.21-7.72, p = 0.018) were predictive of 6-month stroke. Conversely, antiplatelet therapy and anticoagulation were protective factors at both 30 days and 6 months.

CONCLUSIONS

Stroke after TAVR was rare. Predilatation was the only procedural factor predictive of 30-day stroke, whereas the remaining were patient-related risk factors, suggesting appropriate risk stratification preoperatively.

Cardiac surgery-Associated acute kidney injury - A narrative review

Cardiac Surgery-Associated Acute Kidney Injury (CSA-AKI) is a serious complication seen in approximately 20-30% of cardiac surgery patients. The underlying pathophysiology is complex, often involving both patient- and procedure related risk factors. In contrast to AKI occurring after other types of major surgery, the use of cardiopulmonary bypass comprises both additional advantages and challenges, including non-pulsatile flow, targeted blood flow and pressure as well as the ability to manipulate central venous pressure (congestion). With an increasing focus on the impact of CSA-AKI on both short and long-term mortality, early identification and management of high-risk patients for CSA-AKI has evolved. The present narrative review gives an up-to-date summary on definition, diagnosis, underlying pathophysiology, monitoring and implications of CSA-AKI, including potential preventive interventions. The review will provide the reader with an in-depth understanding of how to identify, support and provide a more personalized and tailored perioperative management to avoid development of CSA-AKI.

HCG18, LEF1AS1 and lncCEACAM21 as biomarkers of disease severity in the peripheral blood mononuclear cells of COVID-19 patients

BACKGROUND

Even after 3 years from SARS-CoV-2 identification, COVID-19 is still a persistent and dangerous global infectious disease. Significant improvements in our understanding of the disease pathophysiology have now been achieved. Nonetheless, reliable and accurate biomarkers for the early stratification of COVID-19 severity are still lacking. Long noncoding RNAs (LncRNAs) are ncRNAs longer than 200 nucleotides, regulating the transcription and translation of protein-coding genes and they can be found in the peripheral blood, thus holding a promising biomarker potential. Specifically, peripheral blood mononuclear cells (PBMCs) have emerged as a source of indirect biomarkers mirroring the conditions of tissues: they include monocytes, B and T lymphocytes, and natural killer T cells (NKT), being highly informative for immune-related events.

METHODS

We profiled by RNA-Sequencing a panel of 2906 lncRNAs to investigate their modulation in PBMCs of a pilot group of COVID-19 patients, followed by qPCR validation in 111 hospitalized COVID-19 patients.

RESULTS

The levels of four lncRNAs were found to be decreased in association with COVID-19 mortality and disease severity: HLA Complex Group 18-242 and -244 (HCG18-242 and HCG18-244), Lymphoid Enhancer Binding Factor 1-antisense 1 (LEF1-AS1) and lncCEACAM21 (i.e. ENST00000601116.5, a lncRNA in the CEACAM21 locus). Interestingly, these deregulations were confirmed in an independent patient group of hospitalized patients and by the re-analysis of publicly available single-cell transcriptome datasets. The identified lncRNAs were expressed in all of the PBMC cell types and inversely correlated with the neutrophil/lymphocyte ratio (NLR), an inflammatory marker. In vitro, the expression of LEF1-AS1 and lncCEACAM21 was decreased upon THP-1 monocytes exposure to a relevant stimulus, hypoxia.

CONCLUSION

The identified COVID-19-lncRNAs are proposed as potential innovative biomarkers of COVID-19 severity and mortality.

2021 MiECTiS focused update on the 2016 position paper for the use of minimal invasive extracorporeal circulation in cardiac surgery

The landmark 2016 Minimal Invasive Extracorporeal Technologies International Society (MiECTiS) position paper promoted the creation of a common language between cardiac surgeons, anesthesiologists and perfusionists which led to the development of a stable framework that paved the way for the advancement of minimal invasive perfusion and related technologies. The current expert consensus document offers an update in areas for which new evidence has emerged. In the light of published literature, modular minimal invasive extracorporeal circulation (MiECC) has been established as a safe and effective perfusion technique that increases biocompatibility and ultimately ensures perfusion safety in all adult cardiac surgical procedures, including re-operations, aortic arch and emergency surgery. Moreover, it was recognized that incorporation of MiECC strategies advances minimal invasive cardiac surgery (MICS) by combining reduced surgical trauma with minimal physiologic derangements. Minimal Invasive Extracorporeal Technologies International Society considers MiECC as a physiologically-based multidisciplinary strategy for performing cardiac surgery that is associated with significant evidence-based clinical benefit that has accrued over the years. Widespread adoption of this technology is thus strongly advocated to obtain additional healthcare benefit while advancing patient care.

Characterization of cardiovascular and cerebrovascular controls via spectral causality analysis in patients undergoing surgical aortic valve replacement during a three-month follow-up

Objective.Aortic valve stenosis (AVS) induces left ventricular function adaptations and surgical aortic valve replacement (SAVR) restores blood flow profile across aortic valve. Modifications of cardiac hemodynamics induced by AVS and SAVR might alter cardiovascular (CV) and cerebrovascular (CBV) controls. The study aims at characterizing CV and CBV regulations one day before SAVR (PRE), within one week after SAVR (POST), and after a three-month follow-up (POST3) in 73 AVS patients (age: 63.9 ± 12.9 yrs; 48 males, 25 females) from spontaneous fluctuations of heart period (HP), systolic arterial pressure, mean arterial pressure and mean cerebral blood velocity.Approach.CV and CBV regulations were typified via a bivariate autoregressive approach computing traditional frequency domain markers and causal squared coherence (CK2) from CV and CBV variabilities. Univariate time and frequency domain indexes were calculated as well. Analyses were carried out in frequency bands typical of CV and CBV controls at supine rest and during active standing. A surrogate method was exploited to check uncoupling condition.Main results.We found that: (i) CV regulation is impaired in AVS patients; (ii) CV regulation worsens in POST; (iii) CV regulation recovers in POST3 and CV response to active standing is even better than in PRE; (iv) CBV regulation is preserved in AVS patients; (v) SAVR does not affect CBV control; (vi) parameters of the CBV control in POST3 and PRE are similar.Significance.CK2is particularly useful to characterize CV and CBV controls in AVS patients and to monitor of patient's evolution after SAVR.

Financial Burden of Transcatheter Aortic Valve Implantation

Given the increasing population eligible for transcatheter aortic valve implantation (TAVI), resource utilization has become an important focus in this setting. We aimed to estimate the change in the financial burden of TAVI therapy over 2 different periods. A probabilistic Markov model was developed to estimate the cost consequences of increased center experience and the introduction of newer-generation TAVI devices compared with an earlier TAVI period in a cohort of 6,000 patients. The transition probabilities and hospitalization costs were retrieved from the OBSERVANT (Observational Study of Effectiveness of AVR-TAVI procedures for severe Aortic steNosis Treatment) and OBSERVANT II (Observational Study of Effectiveness of TAVI with new generation deVices for severe Aortic stenosis Treatment) studies, including 1,898 patients treated with old-generation devices and 1,417 patients treated with new-generation devices. The propensity score matching resulted in 853 pairs, with well-balanced baseline risk factors. The mean EuroSCORE II (6.6% vs 6.8%, p = 0.76) and the mean age (82.0 vs 82.1 y, p = 0.62) of the early TAVI period and new TAVI period were comparable. The new TAVI period was associated with a significant reduction in rehospitalizations (-30.5% reintervention, -25.2% rehospitalization for major events, and -30.8% rehospitalization for minor events) and a 20% reduction in 1-year mortality. These reductions resulted in significant cost savings over a 1-year period (-€4.1 million in terms of direct costs and -€19.7 million considering the additional cost of the devices). The main cost reduction was estimated for rehospitalization, accounting for 79% of the overall cost reduction (not considering the costs of the devices). In conclusion, the introduction of new-generation TAVI devices, along with increased center experience, led to significant cost savings at 1-year compared with an earlier TAVI period, mainly because of the reduction in rehospitalization costs.

The current clinical practice for management of post-infarction ventricular septal rupture: a European survey

Aims

Many historical and recent reports showed that post-infarction ventricular septal rupture (VSR) represents a life-threatening condition and the strategy to optimally manage it remains undefined. Therefore, disparate treatment policies among different centres with variable results are often described. We analysed data from European centres to capture the current clinical practice in VSR management.

Methods and results

Thirty-nine centres belonging to eight European countries participated in a survey, filling a digital form of 38 questions from April to October 2022, to collect information about all the aspects of VSR treatment. Most centres encounter 1-5 VSR cases/year. Surgery remains the treatment of choice over percutaneous closure (71.8% vs. 28.2%). A delayed repair represents the preferred approach (87.2%). Haemodynamic conditions influence the management in almost all centres, although some try to achieve patients stabilization and delayed surgery even in cardiogenic shock. Although 33.3% of centres do not perform coronarography in unstable patients, revascularization approaches are widely variable. Most centres adopt mechanical circulatory support (MCS), mostly extracorporeal membrane oxygenation, especially pre-operatively to stabilize patients and achieve delayed repair. Post-operatively, such MCS are more often adopted in patients with ventricular dysfunction.

Conclusion

In real-life, delayed surgery, regardless of the haemodynamic conditions, is the preferred strategy for VSR management in Europe. Extracorporeal membrane oxygenation is becoming the most frequently adopted MCS as bridge-to-operation. This survey provides a useful background to develop dedicated, prospective studies to strengthen the current evidence on VSR treatment and to help improving its currently unsatisfactory outcomes.

Link Between Cardiovascular and Cerebrovascular Controls in Patients Undergoing Surgical Aortic Valve Replacement

Although the autonomic influence on cardiovascular (CV) and cerebrovascular (CBV) regulations has been widely recognized, their relationship is poorly explored especially in pathological situations. This study investigates the correlation between CV and CBV markers in 73 patients (48 males, age 63.6±13.1 yrs) undergoing surgical aortic valve replacement (SAVR) evaluated before the intervention (PRE), within 1-week post-surgery (POST) and after a 3-month follow-up (POST3). Patients were acquired before and after an orthostatic challenge. Frequency domain analysis assessing transfer function gain (TFG), phase (Ph), and squared coherence (K2) between heart period and systolic arterial pressure was exploited to evaluate CV control. The same frequency domain functions were derived to assess CBV regulation from mean cerebral blood velocity and mean arterial pressure. A correlation analysis between indexes of CV and CBV controls was carried out. Results showed that CV control was impaired in PRE, worsened in POST, and recovered in POST3, while CBV markers were almost unchanged. A significant positive relationship between CV and CBV markers was observed, especially in POST and POST3, thus suggesting that the compensation of a baroreflex impairment with a more efficient CBV control and vice versa. The maintenance of this relationship between CV and CBV controls in patients undergoing SAVR could be fundamental to prevent risky situations.Clinical Relevance- After surgical aortic valve replacement an impaired baroreflex control could be compensated by a more efficient cerebral autoregulation.

Plasma-Free Strategy for Cardiac Surgery with Cardiopulmonary Bypass in Infants < 10 kg: A Retrospective, Propensity-Matched Study

BACKGROUND

Infants < 10 kg undergoing cardiac surgery with cardiopulmonary bypass (CPB) may receive either fresh frozen plasma (FFP) or other solutions in the CPB priming volume. The existing comparative studies are controversial. No study addressed the possibility of total avoidance of FFP throughout the whole perioperative course in this patient population. This retrospective, non-inferiority, propensity-matched study investigates an FFP-free strategy compared to an FFP-based strategy.

METHODS

Among patients <10 kg with available viscoelastic measurements, 18 patients who received a total FFP-free strategy were compared to 27 patients (1:1.5 propensity matching) receiving an FFP-based strategy. The primary endpoint was chest drain blood loss in the first 24 postoperative hours. The level of non-inferiority was settled at a difference of 5 mL/kg.

RESULTS

The 24-h chest drain blood loss difference between groups was -7.7 mL (95% confidence interval -20.8 to 5.3) in favor of the FFP-based group, and the non-inferiority hypothesis was rejected. The main difference in coagulation profile was a lower level of fibrinogen concentration and FIBTEM maximum clot firmness in the FFP-free group immediately after protamine, at the admission in the ICU and for 48 postoperative hours. No differences in transfusion of red blood cells or platelet concentrate were observed; patients in the FFP-free group did not receive FFP but required a larger dose of fibrinogen concentrate and prothrombin complex concentrate.

CONCLUSIONS

An FFP-free strategy in infants < 10 kg operated with CPB is technically feasible but results in an early post-CPB coagulopathy that was not completely compensated with our bleeding management protocol.

The Importance of Being the Morning Case in Adult Cardiac Surgery: A Propensity-Matched Analysis

OBJECTIVES

The quality of the outcome after cardiac surgery with cardiopulmonary bypass depends on the patient demographics, co-morbidities, complexity of the surgical procedure, and expertise of surgeons and the whole staff. The purpose of the present study is to analyze the timing of surgery (morning vs afternoon) with respect to morbidity and mortality in adult cardiac surgery. Methods: The primary end-point was the incidence of major morbidity defined according to a modified Society of Thoracic Surgeon criterion. We consecutively included all the adult (> 18 years) patients receiving a cardiac surgery operation at our Institution.

RESULTS

From 2017 through 2019 a total of 4,003 cardiac surgery patients were operated. With a propensity-matching technique a final patient population of 1600 patients was selected, with 800 patients in the first-case surgery group and 800 in the second-case surgery group. Patients in the second-case group had a major morbidity rate of 13% vs 8.8% in the first-case group (P = 0.006), and a higher rate of 30-days mortality (4.1% vs 2.3%, P = 0.033). After correction for EuroSCORE and operating surgeon, the second-case group confirmed a higher rate of major morbidity (odds ratio 1.610, 95% confidence interval 1.16-2.23, P = 0.004).

CONCLUSION

Our study suggests that patients operated as second cases are exposed to an increased morbidity and mortality probably due to fatigue, loss of attention and hurriedness in the operating room, and decreased human resources in the intensive care unit.

Clopidogrel Resistance and Ticagrelor Replacement in Dual Antiplatelet Therapy for Carotid Artery Stenting

BACKGROUNDS

Resistance to the pharmacological effect of clopidogrel in patients undergoing dual antiplatelet therapy for carotid stenting may increase the risk of periprocedural neurological events. The purpose of the study was to describe the phenomenon of clopidogrel resistance in a series of patients undergoing carotid stenting.

METHODS

Data of patients who consecutively underwent carotid stenting from November 2016 to December 2020 for a significant stenosis and who underwent a dual antiplatelet therapy using acetyl-salicylic acid and clopidogrel were prospectively collected. Patients who were already taking a different thienopyridine were excluded. The effectiveness of antiplatelet drugs was assessed by the impedance aggregometry test. Primary endpoint was to evaluate the incidence of clopidogrel resistance and the effectiveness of ticagrelor as alternative therapy. P values < 0.05 were considered statistically significant.

RESULTS

Two-hundred patients (80 females, 40%) underwent stenting for carotid stenosis (94% asymptomatic). The phenomenon of clopidogrel resistance was observed in 38 patients (19%), in whom clopidogrel was replaced by ticagrelor (90 mg/bis in die) with 100% effectiveness at aggregometry test. Platelet counts was associated to clopidogrel resistance (P = 0.001). There was no stent thrombosis at 30 days, neither major hemorrhagic events; a total of 12/200 major adverse cardiovascular events occurred (6%), including 1 in the group of patients who took ticagrelor and 11 in group of patients under clopidogrel (2.6% versus 6.7%, P = 0.55).

CONCLUSIONS

Clopidogrel was ineffective in 19% of patients undergoing carotid stenting. Platelet count seemed to affect this phenomenon. In these patients, clopidogrel was effectively replaced by ticagrelor.

The Very Long COVID: Persistence of Symptoms after 12-18 Months from the Onset of Infection and Hospitalization

According to the World Health Organization's definition, long COVID is the persistence or development of new symptoms 3 months after the initial infection. Various conditions have been explored in studies with up to one-year follow-up but very few looked further. This prospective cohort study addresses the presence of a wide spectrum of symptoms in 121 patients hospitalized during the acute phase of COVID-19 infection, and the association between factors related to the acute phase of the disease and the presence of residual symptoms after one year or longer from hospitalization. The main results are as follows: (i) post-COVID symptoms persist in up to 60% of the patient population at a mean follow-up of 17 months; (ii) the most frequent symptoms are fatigue and dyspnea, but neuropsychological disturbances persist in about 30% of the patients (iii) when corrected for the duration of follow-up with a freedom-from-event analysis; only complete (2 doses) vaccination at the time of hospital admission remained independently associated with persistence of the major physical symptoms, while vaccination and previous neuropsychological symptoms remained independently associated with persistence of major neuropsychological symptoms.

In-hospital and 6-month outcomes in patients with COVID-19 supported with extracorporeal membrane oxygenation (EuroECMO-COVID): a multicentre, prospective observational study

BACKGROUND

Extracorporeal membrane oxygenation (ECMO) has been widely used in patients with COVID-19, but uncertainty remains about the determinants of in-hospital mortality and data on post-discharge outcomes are scarce. The aims of this study were to investigate the variables associated with in-hospital outcomes in patients who received ECMO during the first wave of COVID-19 and to describe the status of patients 6 months after ECMO initiation.

METHODS

EuroECMO-COVID is a prospective, multicentre, observational study developed by the European Extracorporeal Life Support Organization. This study was based on data from patients aged 16 years or older who received ECMO support for refractory COVID-19 during the first wave of the pandemic-from March 1 to Sept 13, 2020-at 133 centres in 21 countries. In-hospital mortality and mortality 6 months after ECMO initiation were the primary outcomes. Mixed-Cox proportional hazards models were used to investigate associations between patient and management-related variables (eg, patient demographics, comorbidities, pre-ECMO status, and ECMO characteristics and complications) and in-hospital deaths. Survival status at 6 months was established through patient contact or institutional charts review. This study is registered with ClinicalTrials.gov, NCT04366921, and is ongoing.

FINDINGS

Between March 1 and Sept 13, 2020, 1215 patients (942 [78%] men and 267 [22%] women; median age 53 years [IQR 46-60]) were included in the study. Median ECMO duration was 15 days (IQR 8-27). 602 (50%) of 1215 patients died in hospital, and 852 (74%) patients had at least one complication. Multiorgan failure was the leading cause of death (192 [36%] of 528 patients who died with available data). In mixed-Cox analyses, age of 60 years or older, use of inotropes and vasopressors before ECMO initiation, chronic renal failure, and time from intubation to ECMO initiation of 4 days or more were associated with higher in-hospital mortality. 613 patients did not die in hospital, and 547 (95%) of 577 patients for whom data were available were alive at 6 months. 102 (24%) of 431 patients had returned to full-time work at 6 months, and 57 (13%) of 428 patients had returned to part-time work. At 6 months, respiratory rehabilitation was required in 88 (17%) of 522 patients with available data, and the most common residual symptoms included dyspnoea (185 [35%] of 523 patients) and cardiac (52 [10%] of 514 patients) or neurocognitive (66 [13%] of 512 patients) symptoms.

INTERPRETATION

Patient's age, timing of cannulation (<4 days vs ≥4 days from intubation), and use of inotropes and vasopressors are essential factors to consider when analysing the outcomes of patients receiving ECMO for COVID-19. Despite post-discharge survival being favourable, persisting long-term symptoms suggest that dedicated post-ECMO follow-up programmes are required.

FUNDING

None.

The Conundrum of Systemic Arterial Pressure Management on Cardiopulmonary Bypass

The recently released EACTS/EACTA/EBCP guidelines on cardiopulmonary bypass (CPB) in adult cardiac surgery [...].

The Rise and Fall of Antithrombin Supplementation in Cardiac Surgery

Various cohort studies, both retrospective and prospective, showed that low antithrombin levels after cardiac surgery (at the arrival in the intensive care unit and during the next days) were associated with a number of adverse outcomes, including surgical reexploration and thromboembolic events, eventually leading to prolonged stay in the intensive care. Values lower than 58% to 64% of antithrombin activity were indicative of this higher morbidity with good sensitivity and specificity. The scenario generated the hypothesis that low antithrombin levels needed to be corrected by supplementation to improve postoperative outcome. However, randomized controlled studies run to test this idea failed to demonstrate any benefit of antithrombin supplementation, showing no effects on outcome, neither as preemptive preoperative strategy nor for treating postoperative low antithrombin values. In addition, randomized trials highlighted that those patients who received antithrombin experienced significantly higher incidence of acute kidney injury with a pooled odds ratio of 4.41 (95% CI, 1.90-10.23; P = .001). A strongly decreased thrombin activity after antithrombin correction may eventually affect the efficiency of the glomerular filtration and cause the deterioration of kidney function, but underlying biological mechanisms remain unclear. In conclusion, low levels of antithrombin activity after cardiac surgery should be considered as a marker of greater severity of the patient's conditions and/or of the complexity of the surgical procedure. There are no indications for antithrombin supplementation in cardiac surgery unless for correcting heparin resistance.

Are Viscoelastic Tests Clinically Useful to Identify Platelet-Dependent Bleeding in High-Risk Cardiac Surgery Patients?

BACKGROUND

Postoperative use of platelet function testing to rule out microvascular bleeding due to platelet dysfunction after cardiac surgery still lacks strong reference data and reliable cutoff values, yielding a clinically adequate sensitivity and specificity. The present study aims to investigate the performance of two different point-of-care viscoelastic devices and platelet aggregometry in expressing surgery-dependent platelet dysfunction and anticipating postoperative major bleeding in a cohort of high-risk patients.

METHODS

Prospective cohort study of 50 adult patients who were on antiplatelet drugs discontinued for no more than 7 days (clopidogrel and prasugrel) or 5 days (ticagrelor) undergoing cardiac surgery with cardiopulmonary bypass (CPB). Coagulation and platelet function testing, including QUANTRA, ROTEM, and Multiplate, were assessed preoperatively and postoperatively. Chest drain blood loss was measured in the first 12 postoperative hours. Perioperative bleeding was assessed using a modified version of the Universal Definition of Perioperative Bleeding (UDPB) in cardiac surgery, modified to not consider anemia-correcting packed red cells transfusions in the absence of bleeding >600 mL/12 h. Major bleeding was identified as UDPB class II or higher.

RESULTS

Multiplate adenosine diphosphate (ADPtest) was significantly ( P = .001) reduced after CPB, whereas TRAPtest was not. The platelet component (PC) as extrapolated by ROTEM data (EXTEM MCF-FIBTEM MCF) was unchanged after CPB, while the A10 PC (PC at 10 minutes) was significantly ( P = .001) reduced. The QUANTRA platelet contribution to clot stiffness (PCS) was significantly ( P = .001) reduced, as well. At the ROC analysis for the predictive ability of the post-CPB platelet function testing, the best discrimination was obtained by the QUANTRA PCS, with an area under the curve (AUC) (95% confidence interval [CI]) of 0.80 (0.66-0.91), P = .001, followed by the ROTEM A10 PC with AUC (95% CI) of 0.75 (0.51-0.99), P = .004, and PC with AUC (95% CI) of 0.74 (0.50-0.99), P = .009. The Multiplate ADPtest had an AUC (95% CI) of 0.67 (0.42-0.91), and the TRAPtest had an AUC (95% CI) of 0.62 (0.37-0.86). The cutoff values identified were 13 hPa for the QUANTRA PCS, 40 mm for the ROTEM A10, and 48.5 mm for the ROTEM PC, with negative predictive values of 84%, 81%, and 86%, respectively, and positive predictive values of 55%, 53%, and 69%, respectively.

CONCLUSIONS

QUANTRA PCS, ROTEM A10 PC, and Multiplate ADPtest showed a significant decrease after CPB, whereas ROTEM PC and Multiplate TRAPtest did not. Major bleeding was predicted with a moderate to good discrimination by the post-CPB viscoelastic tests (PCS, PC, and A10 PC).

Association of miR-144 levels in the peripheral blood with COVID-19 severity and mortality

Coronavirus disease-2019 (COVID-19) can be asymptomatic or lead to a wide symptom spectrum, including multi-organ damage and death. Here, we explored the potential of microRNAs in delineating patient condition and predicting clinical outcome. Plasma microRNA profiling of hospitalized COVID-19 patients showed that miR-144-3p was dynamically regulated in response to COVID-19. Thus, we further investigated the biomarker potential of miR-144-3p measured at admission in 179 COVID-19 patients and 29 healthy controls recruited in three centers. In hospitalized patients, circulating miR-144-3p levels discriminated between non-critical and critical illness (AUC_miR-144-3p = 0.71; p = 0.0006), acting also as mortality predictor (AUC_miR-144-3p = 0.67; p = 0.004). In non-hospitalized patients, plasma miR-144-3p levels discriminated mild from moderate disease (AUC_miR-144-3p = 0.67; p = 0.03). Uncontrolled release of pro-inflammatory cytokines can lead to clinical deterioration. Thus, we explored the added value of a miR-144/cytokine combined analysis in the assessment of hospitalized COVID-19 patients. A miR-144-3p/Epidermal Growth Factor (EGF) combined score discriminated between non-critical and critical hospitalized patients (AUC_{miR-144-3p/EGF} = 0.81; p < 0.0001); moreover, a miR-144-3p/Interleukin-10 (IL-10) score discriminated survivors from nonsurvivors (AUC_{miR-144-3p/IL-10} = 0.83; p < 0.0001). In conclusion, circulating miR-144-3p, possibly in combination with IL-10 or EGF, emerges as a noninvasive tool for early risk-based stratification and mortality prediction in COVID-19.

Early and mid-term outcome of patients with low-flow-low-gradient aortic stenosis treated with newer-generation transcatheter aortic valves

Patients with non-paradoxical low-flow-low-gradient (LFLG) aortic stenosis (AS) are at increased surgical risk, and thus, they may particularly benefit from transcatheter aortic valve replacement (TAVR). However, data on this issue are still limited and based on the results with older-generation transcatheter heart valves (THVs). The aim of this study was to investigate early and mid-term outcome of TAVR with newer-generation THVs in the setting of LFLG AS. Data for the present analysis were gathered from the OBSERVANT II dataset, a national Italian observational, prospective, multicenter cohort study that enrolled 2,989 consecutive AS patients who underwent TAVR at 30 Italian centers between December 2016 and September 2018, using newer-generation THVs. Overall, 420 patients with LVEF ≤50% and mean aortic gradient <40 mmHg were included in this analysis. The primary outcomes were 1-year all-cause mortality and a combined endpoint including all-cause mortality and hospital readmission due to congestive heart failure (CHF) at 1 year. A risk-adjusted analysis was performed to compare the outcome of LFLG AS patients treated with TAVR (n = 389) with those who underwent surgical aortic valve replacement (SAVR, n = 401) from the OBSERVANT I study. Patients with LFLG AS undergoing TAVR were old (mean age, 80.8 ± 6.7 years) and with increased operative risk (mean EuroSCORE II, 11.5 ± 10.2%). VARC-3 device success was 83.3% with 7.6% of moderate/severe paravalvular leak. Thirty-day mortality was 3.1%. One-year all-cause mortality was 17.4%, and the composite endpoint was 34.8%. Chronic obstructive pulmonary disease (HR 1.78) and EuroSCORE II (HR 1.02) were independent predictors of 1-year mortality, while diabetes (HR 1.53) and class NYHA IV (HR 2.38) were independent predictors of 1-year mortality or CHF. Compared with LFLG AS treated with SAVR, TAVR patients had a higher rate of major vascular complications and permanent pacemaker, while SAVR patients underwent more frequently to blood transfusion, cardiogenic shock, AKI, and MI. However, 30-day and 1-year outcomes were similar between groups. Patients with non-paradoxical LFLG AS treated by TAVR were older and with higher surgical risk compared with SAVR patients. Notwithstanding, TAVR was safe and effective with a similar outcome to SAVR at both early and mid-term.

P17.17.A Metformin, tmCLIC1 and transcranial stimulation: the basis of a new targeted therapy against glioblastoma relapse

Background

Glioblastoma (GBM) is the most common brain tumor with an extremely poor prognosis. Standard therapy relies on surgery, chemo- and radiotherapy but tumor relapse occurs inevitably with fatal outcome. Hence, new approaches should be designed to increase patients’ life expectancy. The high grade of aggressiveness and recurrence is attributed to GBM stem-like cells (GSCs). Recent publications propose the transmembrane Chloride Intracellular Channel 1 protein (tmCLIC1) as a potential pharmacological target since it is crucial for GSCs proliferation both in vitro and in vivo. Recently, we proposed tmCLIC1 to be one of metformin’s targets. Here, we show molecular evidence of direct metformin-tmCLIC1 interaction. However, the high concentration of metformin needed to impair tumor progression cannot be reached in the brain due to the blood brain barrier. Hence, the main aim of this work is to decrease metformin’s operative concentration to the level that can access the brain. Our strategy is to induce repetitive membrane depolarizations to the tumoral area to promote metformin-tmCLIC1 interaction, that only occurs when tmCLIC1 is in the open state. Pulsed depolarizing electromagnetic field (EMF) stimulation should increase tmCLIC1 close-to-open transitions and, consequently, the availability of metformin binding sites.

Material and Methods

We generated CLIC1-knockout of several patient-derived GSCs using CRISPR-Cas9 technology to assess the role of CLIC1 in metformin’s antiproliferative effect. In the first set of experiments, we used 10mM metformin. When applying concomitant EMF stimulation, we dropped to 1mM metformin. NMR experiments and single-channel electrophysiological recordings were provided to study metformin-tmCLIC1 interaction. Metformin-EMF system was applied in vitro on GSCs cultures and spheroids, and in vivo on zebrafish embryos and mice.

Results

NMR and electrophysiology demonstrate the direct binding between metformin and tmCLIC1, that figures as the main metformin receptor in GBM. The application of EMF stimulation resulted in a 10-fold decrease of metformin concentration to get the same antiproliferative effect in vitro. To assess whether the effect is maintained in vivo, zebrafish embryos were orthotopically injected with GSCs and the tumor mass was measured after 72 hours in absence or presence of metformin in embryos’ water and of EMF stimulation. Consistently, metformin coupled to EMF reduces tumor progression in zebrafish embryos to the same extent of metformin 10mM alone. Experiments on mice are currently on-going.

Conclusion

Our research has revealed a new interactor of metformin. The combination of metformin and EMF results in an effective strategy to impair GBM progression both in vitro and in vivo. The long-term goal is to combine transcranial stimulation and metformin administration to patients as an adjuvant therapy. AIRC#24758

Influence of left ventricular unloading on pediatric post-cardiotomy veno-arterial extracorporeal life support outcomes

Background

The effectiveness of veno-arterial extracorporeal life support (V-A ECLS) in treating neonatal and pediatric patients with complex congenital heart disease (CHD) and requiring cardio-circulatory assistance is well-known. Nevertheless, the influence of left ventricle (LV) distension and its countermeasure, namely LV unloading, on survival and clinical outcomes in neonates and children treated with V-A ECLS needs still to be addressed. Therefore, the aim of this study was to determine the effects of LV unloading on in-hospital survival and complications in neonates and children treated with V-A ECLS.

Methods

The clinical outcomes of 90 pediatric patients with CHD under 16 years of age supported with V-A ECLS for post-cardiotomy cardiogenic shock (CS) were retrospectively reviewed in relationship with the presence or absence of an active LV unloading strategy.

Results

The patient cohort included 90 patients (age 19.6 ± 31.54 months, 64.4% males), 42 of whom were vented with different techniques (38 with atrial septostomy (AS) or left atria cannula, two with cannula from LV apex, 1 with intra-aortic balloon pump (IABP), and one with pigtail across the aortic valve). The LV unloading strategy significantly increased the in-hospital survival (odds ratio [OR] = 2.74, 95% CI 1.06–7.08; p = 0.037). On the contrary, extracorporeal cardiopulmonary resuscitation decreased the related survival (OR = 0.32, 95% CI 1.09–0.96; p = 0.041). The most common complications were infections (28.8%), neurological injury (26%), and bleeding (25.6%). However, these did not differently occur in venting and no-venting groups.

Conclusion

In pediatric patients with CHD supported with V-A ECLS for post-cardiotomy CS, the LV unloading strategy was associated with increased survival.

A Multicenter, Randomized, Double-Blind, Placebo-Controlled Trial of Preoperative Antithrombin Supplementation in Patients at Risk for Antithrombin Deficiency After Cardiac Surgery

BACKGROUND

Antithrombin (AT) activity is reduced during cardiac operations with cardiopulmonary bypass (CPB), which is associated with adverse outcomes. Preoperative AT supplementation, to achieve >58% and <100% AT activity, may potentially reduce postoperative morbidity and mortality in cardiac operations with CPB. This prospective, multicenter, randomized, double-blind, placebo-controlled study was designed to evaluate the safety and efficacy of preoperative treatment with AT supplementation in patients at risk for low AT activity after undergoing cardiac surgery with CPB.

METHODS

A total of 425 adult patients were randomized (1:1) to receive either a single dose of AT (n = 213) to achieve an absolute increase of 20% above pretreatment AT activity or placebo (n = 212) before surgery. The study duration was approximately 7 weeks. The primary efficacy end point was the percentage of patients with any component of a major morbidity composite (postoperative mortality, stroke, acute kidney injury [AKI], surgical reexploration, arterial or venous thromboembolic events, prolonged mechanical ventilation, and infection) in the 2 groups. Secondary end points included AT activity, blood loss, transfusion requirements, duration of intensive care unit (ICU), and hospital stays. Safety was also assessed.

RESULTS

Overall, 399 patients (men, n = 300, 75.2%) with a mean (standard deviation [SD]) age of 66.1 (11.7) years, with the majority undergoing complex surgical procedures (n = 266, 67.9%), were analyzed. No differences in the percentage of patients experiencing morbidity composite outcomes between groups were observed (AT-treated 68/198 [34.3%] versus placebo 58/194 [29.9%]; P = .332; relative risk, 1.15). After AT infusion, AT activity was significantly higher in the AT group (108% [42-143]) versus placebo group (76% [40-110]), and lasted up to postoperative day 2. At ICU, the frequency of patients with AT activity ≥58% in the AT group (81.5%) was significantly higher (P < .001) versus placebo group (43.2%). Secondary end point analysis did not show any advantage of AT over placebo group. There were significantly more patients with AKI (P < .001) in the AT group (23/198; 11.6%) than in the placebo group (5/194, 2.6%). Safety results showed no differences in treatment-emergent adverse events nor bleeding events between groups.

CONCLUSIONS

AT supplementation did not attenuate adverse postoperative outcomes in our cohort of patients undergoing cardiac surgery with CPB.

When Outcomes Diverge: Age and Cardiovascular Risk as Determinants of Mortality and ICU Admission in COVID-19

Background: Hospital mortality and admission to the Intensive Care Unit (ICU) are markers of disease severity in COVID-19 patients. Cardiovascular co-morbidities are one of the main determinants of negative outcomes. In this study we investigated the impact of cardiovascular co-morbidities on mortality and admission to the ICU in first-wave COVID-19 patients. Methods: A multicenter, retrospective, cohort study. A total of 1077 patients were analyzed for mortality and ICU admission. Cardiovascular risk factors were explored as determinants of the outcomes after correction for other confounders. Results: In the multivariable model, after correction for age, only a history of heart failure remained independently associated (p = 0.0013) with mortality (hazard ratio 2.22, 95% confidence interval 1.37 to 3.62). Age showed a mortality risk increase of 8% per year (hazard ratio 1.08, 95% confidence interval 1.05 to 1.10, p = 0.001). The transition from ward to the ICU had, as a single determinant, the age, but in a reversed fashion (hazard ratio 0.96, 95% confidence interval 0.94 to 0.98, p = 0.0002). Conclusions: Once adjusted for the main determinant of mortality (age) heart failure only remained independently associated with mortality. Admission to the ICU was less likely for elderly patients. This may reflect the catastrophic impact of the first wave of COVID-19 pandemic in terms of ICU bed availability in Lombardy, leading to a selection process for ICU admission.

Acute Respiratory Distress Syndrome in the Perioperative Period of Cardiac Surgery: Predictors, Diagnosis, Prognosis, Management Options, and Future Directions

Acute respiratory distress syndrome (ARDS) after cardiac surgery is reported with a widely variable incidence (from 0.4%-8.1%). Cardiac surgery patients usually are affected by several comorbidities, and the development of ARDS significantly affects their prognosis. Herein, evidence regarding the current knowledge in the field of ARDS in cardiac surgery is summarized and is followed by a discussion on therapeutic strategies, with consideration of the peculiar aspects of ARDS after cardiac surgery. Prevention of lung injury during and after cardiac surgery remains pivotal. Blood product transfusions should be limited to minimize the risk, among others, of lung injury. Open lung ventilation strategy (ventilation during cardiopulmonary bypass, recruitment maneuvers, and the use of moderate positive end-expiratory pressure) has not shown clear benefits on clinical outcomes. Clinicians in the intraoperative and postoperative ventilatory settings carefully should consider the effect of mechanical ventilation on cardiac function (in particular the right ventricle). Driving pressure should be kept as low as possible, with low tidal volumes (on predicted body weight) and optimal positive end-expiratory pressure. Regarding the therapeutic options, management of ARDS after cardiac surgery challenges the common approach. For instance, prone positioning may not be easily applicable after cardiac surgery. In patients who develop ARDS after cardiac surgery, extracorporeal techniques may be a valid choice in experienced hands. The use of neuromuscular blockade and inhaled nitric oxide can be considered on a case-by-case basis, whereas the use of aggressive lung recruitment and oscillatory ventilation should be discouraged.

Microcirculatory Alterations in Critically Ill Patients with COVID-19-Associated Acute Respiratory Distress Syndrome

Background: Presently, a number of specific observations have been performed on microcirculatory function in a coronavirus disease-19 (COVID-19) setting. We hypothesized that, in the critically ill, endothelial dysfunction secondary to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection and the subsequent inflammation and coagulopathy may lead to microcirculatory alterations, further exacerbated by the hypoxemic state. A dysfunctional microcirculation may represent the hidden motor underlying the development of COVID-19’s clinical manifestations. Methods: A single center, prospective, observational study. We analyzed bedside sublingual microcirculation in twenty-four consecutive COVID-19-associated acute respiratory distress syndrome (ARDS) patients mechanically ventilated in an Intensive Care Unit (ICU), together with macro-hemodynamics, clinical parameters, echocardiography, and laboratory data at a single time-point after ICU admission. All participants were recruited between March and May 2020. Results: The microcirculatory pattern was characterized by increased values of total vessel density and perfused vessel density, a reduced value of proportion of perfused vessels and microvascular flow index, and high values of heterogeneity index. The duration of mechanical ventilation before microcirculation assessment was inversely associated with the proportion of perfused vessels (p = 0.023). Within the macro-hemodynamic parameters, the right ventricle end-diastolic diameter was inversely associated with proportion of perfused vessels and microvascular flow index (p = 0.039 and 0.014, respectively) and directly associated with the heterogeneity index (p = 0.033). Conclusions: In COVID-19-associated ARDS patients, the microcirculation showed impaired quality of flow parameters coupled with a high vessel density.

Atrial Septostomy for Left Ventricular Unloading During Extracorporeal Membrane Oxygenation for Cardiogenic Shock: Animal Model

OBJECTIVES

The aim of this study was to quantify and understand the unloading effect of percutaneous balloon atrial septostomy (BAS) in acute cardiogenic shock (CS) treated with venoarterial (VA) extracorporeal membranous oxygenation (ECMO).

BACKGROUND

In CS treated with VA ECMO, increased left ventricular (LV) afterload is observed that commonly interferes with myocardial recovery or even promotes further LV deterioration. Several techniques for LV unloading exist, but the optimal strategy and the actual extent of such procedures have not been fully disclosed.

METHODS

In a porcine model (n = 11; weight 56 kg [53-58 kg]), CS was induced by coronary artery balloon occlusion (57 minutes [53-64 minutes]). Then, a step-up VA ECMO protocol (40-80 mL/kg/min) was run before and after percutaneous BAS was performed. LV pressure-volume loops and multiple hemoglobin saturation data were evaluated. The Wilcoxon rank sum test was used to assess individual variable differences.

RESULTS

Immediately after BAS while on VA ECMO support, LV work decreased significantly: pressure-volume area, end-diastolic pressure, and stroke volume to ∼78% and end-systolic pressure to ∼86%, while superior vena cava and tissue oximetry did not change. During elevating VA ECMO support (40-80 mL/kg/min) with BAS vs without BAS, we observed 1) significantly less mechanical work increase (122% vs 172%); 2) no end-diastolic volume increase (100% vs 111%); and 3) a considerable increase in end-systolic pressure (134% vs 144%).

CONCLUSIONS

In acute CS supported by VA ECMO, atrial septostomy is an effective LV unloading tool. LV pressure is a key component of LV work load, so whenever LV work reduction is a priority, arterial pressure should carefully be titrated low while maintaining organ perfusion.

Categorizing the Role of Respiration in Cardiovascular and Cerebrovascular Variability Interactions

OBJECTIVE

Respiration disturbs cardiovascular and cerebrovascular controls but its role is not fully elucidated.

METHODS

Respiration can be classified as a confounder if its observation reduces the strength of the causal relationship from source to target. Respiration is a suppressor if the opposite situation holds. We prove that a confounding/suppression (C/S) test can be accomplished by evaluating the sign of net redundancy/synergy balance in the predictability framework based on multivariate autoregressive modelling. In addition, we suggest that, under the hypothesis of Gaussian processes, the C/S test can be given in the transfer entropy decomposition framework as well. Experimental protocols: We applied the C/S test to variability series of respiratory movements, heart period, systolic arterial pressure, mean arterial pressure, and mean cerebral blood flow recorded in 17 pathological individuals (age: 648 yrs; 17 males) before and after induction of propofol-based general anesthesia prior to coronary artery bypass grafting, and in 13 healthy subjects (age: 278 yrs; 5 males) at rest in supine position and during head-up tilt with a table inclination of 60.

RESULTS

Respiration behaved systematically as a confounder for cardiovascular and cerebrovascular controls. In addition, its role was affected by propofol-based general anesthesia but not by a postural stimulus of limited intensity.

CONCLUSION

The C/S test can be fruitfully exploited to categorize the role of respiration over causal variability interactions.

SIGNIFICANCE

The application of the C/S test could favor the comprehension of the role of respiration in cardiovascular and cerebrovascular regulations.

A Comparative Study of Multiple Electrode Aggregometry Technologies in Cardiac Surgery: Different Values, Same Clinical Relevance

OBJECTIVES

The assessment of platelet function in cardiac surgery patients who recently received dual-antiplatelet therapy is considered in the existing guidelines. Among available devices, Multiplate (MP) and ROTEM Platelet (RP) are both based on electrical impedance. This study aimed to determine the agreement between MP and RP in cardiac surgery patients under dual-antiplatelet therapy discontinued before surgery. Secondarily, it compared the ability of the MP and RP in predicting postoperative bleeding and the need for platelet transfusion.

DESIGN

A prospective cohort study.

SETTING

A hospital in Milan, Italy.

PARTICIPANTS

Fifty adult patients preoperatively and postoperatively tested.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

Patients were studied with adenosine diphosphate (ADP) and thrombin receptor-activating peptide (TRAP) testing on both of the devices. The mean preoperative ADP tests were below the respective lower limit of the reference value, thus reflecting a good ability of these tests to detect the residual or ongoing effects of antiplatelet drugs acting on the P2Y₁₂ receptor. The agreement between the 2 methodologies was very poor for both the ADP and TRAP tests, with a percentage error of 80%. The preoperative ADP tests were predictive for the need of platelet concentrate transfusion, with cut-off values at 35 U for the ADP-MP and 60 Ω/min for the ADP-RP. No correlation was found for postoperative bleeding.

CONCLUSION

Both technologies seemed to offer potential benefits in the surgical approach to patients who preoperatively received antiplatelet drugs. However, the results of these tests are not interchangeable, and different cut-off values should be applied.

Respiration is a Confounder of the Closed Loop Relationship Between Mean Arterial Pressure and Mean Cerebral Blood Flow

This study tested the hypothesis that respiration (RESP) is a confounder or suppressor of the closed loop relationship responsible for the cerebrovascular dynamical interactions as assessed from spontaneous variability of mean arterial pressure (MAP) and mean cerebral blood flow (MCBF). The evaluation was carried out in the information domain via transfer entropy (TE) estimated through a linear model-based approach comparing TE markers computed solely over MAP and MCBF series with TE indexes accounting for the eventual action of RESP over MAP and MCBF. We considered 11 patients (age: 76±5 yrs, 7 males) undergoing surgical aortic valve replacement (SAVR) at supine resting (REST) and during active standing (STAND) before and after SAVR surgery. The decrease of the predictive ability of MCBF to MAP when accounting for RESP compared to the one assessed when disregarding RESP suggested that RESP is a confounder of the link from MCBF to MAP along the Cushing reflex instead of being a suppressor. This result was more evident in POST when autonomic control was dramatically depressed and in an unchallenged condition such as REST. RESP did not affect significantly the link from MAP to MCBF along the pressure-to-flow relationship. Clarification of the type of RESP influence on the MAP-MCBF closed loop relationship could favor a deeper characterization of cerebrovascular interactions and the comprehension of cerebral autoregulation mechanisms.Clinical Relevance- This study suggests that respiration is a confounder of the closed loop relationship between MAP and MCBF, especially of the flow-to-pressure causal link. This result might open new possibilities in elucidating the mechanisms of cerebral autoregulation in healthy and pathological populations.

Surgical Treatment of Postinfarction Ventricular Septal Rupture

IMPORTANCE

Ventricular septal rupture (VSR) is a rare but life-threatening mechanical complication of acute myocardial infarction associated with high mortality despite prompt treatment. Surgery represents the standard of care; however, only small single-center series or national registries are usually available in literature, whereas international multicenter investigations have been poorly carried out, therefore limiting the evidence on this topic.

OBJECTIVES

To assess the clinical characteristics and early outcomes for patients who received surgery for postinfarction VSR and to identify factors independently associated with mortality.

DESIGN, SETTING, AND PARTICIPANTS

The Mechanical Complications of Acute Myocardial Infarction: an International Multicenter Cohort (CAUTION) Study is a retrospective multicenter international cohort study that includes patients who were treated surgically for mechanical complications of acute myocardial infarction. The study was conducted from January 2001 to December 2019 at 26 different centers worldwide among 475 consecutive patients who underwent surgery for postinfarction VSR.

EXPOSURES

Surgical treatment of postinfarction VSR, independent of the technique, alone or combined with other procedures (eg, coronary artery bypass grafting).

MAIN OUTCOMES AND MEASURES

The primary outcome was early mortality; secondary outcomes were postoperative complications.

RESULTS

Of the 475 patients included in the study, 290 (61.1%) were men, with a mean (SD) age of 68.5 (10.1) years. Cardiogenic shock was present in 213 patients (44.8%). Emergent or salvage surgery was performed in 212 cases (44.6%). The early mortality rate was 40.4% (192 patients), and it did not improve during the nearly 20 years considered for the study (median [IQR] yearly mortality, 41.7% [32.6%-50.0%]). Low cardiac output syndrome and multiorgan failure were the most common causes of death (low cardiac output syndrome, 70 [36.5%]; multiorgan failure, 53 [27.6%]). Recurrent VSR occurred in 59 participants (12.4%) but was not associated with mortality. Cardiogenic shock (survived: 95 [33.6%]; died, 118 [61.5%]; P < .001) and early surgery (time to surgery ≥7 days, survived: 105 [57.4%]; died, 47 [35.1%]; P < .001) were associated with lower survival. At multivariate analysis, older age (odds ratio [OR], 1.05; 95% CI, 1.02-1.08; P = .001), preoperative cardiac arrest (OR, 2.71; 95% CI, 1.18-6.27; P = .02) and percutaneous revascularization (OR, 1.63; 95% CI, 1.003-2.65; P = .048), and postoperative need for intra-aortic balloon pump (OR, 2.98; 95% CI, 1.46-6.09; P = .003) and extracorporeal membrane oxygenation (OR, 3.19; 95% CI, 1.30-7.38; P = .01) were independently associated with mortality.

CONCLUSIONS AND RELEVANCE

In this study, surgical repair of postinfarction VSR was associated with a high risk of early mortality; this risk has remained unchanged during the last 2 decades. Delayed surgery seemed associated with better survival. Age, preoperative cardiac arrest and percutaneous revascularization, and postoperative need for intra-aortic balloon pump and extracorporeal membrane oxygenation were independently associated with early mortality. Further prospective studies addressing preoperative and perioperative patient management are warranted to hopefully improve the currently suboptimal outcome.

Enhanced Assessment of Perioperative Mortality Risk in Adults With Congenital Heart Disease

BACKGROUND

In-hospital mortality is a rare, yet feared complication following cardiac surgery in adult congenital heart disease (ACHD). A risk score, developed and validated in ACHD, can be helpful to optimize risk assessment.

OBJECTIVES

The purpose of this study was to assess the performance of EuroSCORE II components and procedure-related Adult Congenital Heart Surgery (ACHS) score, identify additional risk factors, and develop a novel risk score for predicting in-hospital mortality after ACHD surgery.

METHODS

We assessed perioperative survival in patients aged >16 years undergoing congenital heart surgery in a large tertiary center between 2003 and 2019. A risk variable-derived PEACH (PErioperative ACHd) score was calculated for each patient. Internal and external validation of the model was undertaken, including testing in a validation cohort of patients operated in a second European ACHD center.

RESULTS

The development cohort comprised 1,782 procedures performed during the study period. Re-sternotomy was undertaken in 897 (50.3%). There were 31 (1.7%) in-hospital deaths. The PEACH score showed excellent discrimination ability (area under the curve [AUC]: 0.88; 95% CI: 0.83-0.94), and performed better than the ACHS score in our population (ACHS AUC: 0.69; 95% CI: 0.6-0.78; P = 0.0003). A simple 3-tiered risk stratification was formed: PEACH score 0 (in-hospital mortality 0.2%), 1-2 (3.6%), and ≥3 (17.2%). In a validation cohort of 975 procedures, the PEACH score retained its discriminative ability (AUC: 0.75; 95% CI: 0.72-0.77) and was well calibrated (Hosmer-Lemeshow chi-square goodness-of-fit P = 0.55). There was agreement in expected and observed perioperative mortality between cohorts.

CONCLUSIONS

The PEACH score is a simple, novel perioperative risk score developed and validated specifically for ACHD patients undergoing cardiac surgery.

Sensitivity of serology assay in Covid-19 diagnosis: does the antigen matter?

Since the spreading of Sar-CoV-2 in March 2020, many serologic tests have been developed to identify antibody responses. Indeed, different commercial kits are directed against different antigens and could utilise different methods thereby triggering confusion and criticism. Here, we compared two Food and Drug Administration (FDA)-approved automatized assays that detect IgG responses against spike or nucleocapsid protein of Sars-Cov-2 virus in 127 subjects among healthcare workers of IRCCS Policlinico San Donato (MI), Italy. We observed different kinetics of IgG responses, demonstrating the importance of timing of sampling to correctly interpret the results both for infection diagnosis and for epidemiologic studies. We observed that Anti-N response starts earlier than Anti-S1/S2 response but also decreases earlier, affecting the sensitivity of the tests at different time points. Combining two different assays, designed against different antigens, could reduce false negative results. Finally, we observed a patient who produced anti-nucleocapsid IgG, but not anti-spike IgG. In conclusion, we investigated antibody responses in Covid-19 disease, aiming to direct clinicians and laboratory scientists to correctly interpret serologic results by always paying attention to clinical history correlation, timing of sampling, methods and antigens used, to avoid false negative results and obtain relevant epidemiologic data.

Evaluation of the impact of surgical aortic valve replacement on short-term cardiovascular and cerebrovascular controls through spontaneous variability analysis

We assessed the effect of surgical aortic valve replacement (SAVR) on cardiovascular and cerebrovascular controls via spontaneous variability analyses of heart period, approximated as the temporal distance between two consecutive R-wave peaks on the electrocardiogram (RR), systolic, diastolic and mean arterial pressure (SAP, DAP and MAP) and mean cerebral blood flow (MCBF). Powers in specific frequency bands, complexity, presence of nonlinear dynamics and markers of cardiac baroreflex and cerebral autoregulation were calculated. Variability series were acquired before (PRE) and after (POST) SAVR in 11 patients (age: 76±5 yrs, 7 males) at supine resting and during active standing. Parametric spectral analysis was performed based on the autoregressive model. Complexity was assessed via a local nonlinear prediction approach exploiting the k-nearest-neighbor strategy. The presence of nonlinear dynamics was checked by comparing the complexity marker computed over the original series with the distribution of the same index assessed over a set of surrogates preserving distribution and power spectral density of the original series. Cardiac baroreflex and cerebral autoregulation were estimated by assessing the transfer function from SAP to RR and from MAP to MCBF and squared coherence function via the bivariate autoregressive approach. We found that: i) orthostatic challenge had no effect on cardiovascular and cerebrovascular control markers in PRE; ii) RR variance was significantly reduced in POST; iii) complexity of SAP, DAP and MAP variabilities increased in POST with a greater likelihood of observing nonlinear dynamics over SAP compared to PRE at supine resting; iv) the amplitude of MCBF variations and MCBF complexity in POST remained similar to PRE; v) cardiac baroreflex sensitivity decreased in POST, while cerebrovascular autoregulation was preserved. SAVR induces important changes of cardiac and vascular autonomic controls and baroreflex regulation in patients exhibiting poor reactivity of cardiovascular regulatory mechanisms, while cerebrovascular autoregulation seems to be less affected.

Management of critically ill patients with COVID-19: suggestions and instructions from the coordination of intensive care units of Lombardy

With 63,098 confirmed cases on 17 April 2020 and 11,384 deaths, Lombardy has been the most affected region in Italy by coronavirus disease 2019 (COVID-19). To cope with this emergency, the COVID-19 Lombardy intensive care units (ICU) network was created. The network identified the need of defining a list of clinical recommendations to standardize treatment of patients with COVID-19 admitted to Intensive Care Unit (ICU). Three core topics were identified: 1) rational use of intensive care resources; 2) ventilation strategies; 3) non-ventilatory interventions. Identification of patients who may benefit from ICU treatment is challenging. Clinicians should consider baseline performance and frailty status and they should adopt disease-specific staging tools. Continuous positive airway pressure, mainly delivered through a helmet as elective method, should be considered as initial treatment for all patients with respiratory failure associated with COVID-19. In case of persisting dyspnea and/or desaturation despite 4-6 hours of noninvasive ventilation, endotracheal intubation and invasive mechanical ventilation should be considered. In the early phase, muscle relaxant use and volume-controlled ventilation is recommended. Prone position should be performed in patients with PaO<inf>2</inf>/FiO<inf>2</inf>≤100 mmHg. For patients admitted to ICU with COVID-19 interstitial pneumonia, we do not recommend empiric antibiotic therapy for community-acquired pneumonia. Consultation of an infectious disease specialist is suggested before start of any antiviral therapy. In conclusion, the COVID-19 Lombardy ICU Network identified a list of best practice statements supported by the available evidence and clinical experience or identified as panel members expert opinions for the management of critically ill patients with COVID-19.