Preoperative statin therapy for adults undergoing cardiac surgery.

BACKGROUND: Despite significant advances in surgical techniques and perioperative care, people undertaking cardiac surgery due to cardiovascular disease are more prone to the development of postoperative adverse events. Statins (5-hydroxy-3-methylglutaryl-co-enzyme A (HMG-CoA) reductase inhibitors) are well-known for their anti-inflammatory and antioxidant effects and are established for primary and secondary prevention of coronary artery disease. In addition, statins are thought to have clinical benefits in perioperative outcomes in people undergoing cardiac surgery. This review is an update of a review that was first published in 2012 and updated in 2015. OBJECTIVES: To evaluate the benefits and harms of preoperative statin therapy in adults undergoing cardiac surgery compared to standard of care or placebo. SEARCH METHODS: We performed a search of the Cochrane Central Register of Controlled Trials (CENTRAL) (Issue 9, 2023), Ovid MEDLINE (1980 to 14 September 2023), and Ovid Embase (1980 to 2023 (week 36)). We applied no language restrictions. SELECTION CRITERIA: We included all randomised controlled trials (RCTs) comparing any statin treatment before cardiac surgery, for any given duration and dose, versus no preoperative statin therapy (standard of care) or placebo. We excluded trials without a registered trial protocol and trials without approval by an institutional ethics committee. DATA COLLECTION AND ANALYSIS: We used standard Cochrane methodology. Primary outcomes were short-term mortality and major adverse cardiovascular events. Secondary outcomes were myocardial infarction, atrial fibrillation, stroke, renal failure, length of intensive care unit (ICU) stay, length of hospital stay and adverse effects related to statin therapy. We reported effect measures as risk ratios (RRs) or mean differences (MDs) with corresponding 95% confidence intervals (CIs). We used the RoB 1 tool to assess the risk of bias in included trials, and GRADE to assess the certainty of the evidence. MAIN RESULTS: We identified eight RCTs (five new to this review) including 5592 participants. Pooled analysis showed that statin treatment before surgery may result in little to no difference in the risk of postoperative short-term mortality (RR 1.36, 95% CI 0.72 to 2.59; I2 = 0%; 6 RCTs, 5260 participants; low-certainty evidence; note 2 RCTs reported 0 events in both groups so RR calculated from 4 RCTs with 5143 participants). We are very uncertain about the effect of statins on major adverse cardiovascular events (RR 0.93, 95% CI 0.77 to 1.13; 1 RCT, 2406 participants; very low-certainty evidence). Statins probably result in little to no difference in myocardial infarction (RR 0.88, 95% CI 0.73 to 1.06; I2 = 0%; 5 RCTs, 4645 participants; moderate-certainty evidence), may result in little to no difference in atrial fibrillation (RR 0.87, 95% CI 0.72 to 1.05; I2 = 60%; 8 RCTs, 5592 participants; low-certainty evidence), and may result in little to no difference in stroke (RR 1.47, 95% CI 0.90 to 2.40; I2 = 0%; 4 RCTs, 5143 participants; low-certainty evidence). We are very uncertain about the effect of statins on renal failure (RR 1.04, 95% CI 0.80 to 1.34; I2 = 57%; 4 RCTs, 4728 participants; very low-certainty evidence). Additionally, statins probably result in little to no difference in length of ICU stay (MD 1.40 hours, 95% CI -1.62 to 4.41; I2 = 43%; 3 RCTs, 4528 participants; moderate-certainty evidence) and overall hospital stay (MD -0.31 days, 95% CI -0.64 to 0.03; I2 = 84%; 5 RCTs, 4788 participants; moderate-certainty evidence). No study had any individual risk of bias domain classified as high. However, two studies were at high risk of bias overall given the classification of unclear risk of bias in three domains. AUTHORS' CONCLUSIONS: In this updated Cochrane review, we found no evidence that statin use in the perioperative period of elective cardiac surgery was associated with any clinical benefit or worsening, when compared with placebo or standard of care. Compared with placebo or standard of care, statin use probably results in little to no difference in MIs, length of ICU stay and overall hospital stay; and may make little to no difference to mortality, atrial fibrillation and stroke. We are very uncertain about the effects of statins on major harmful cardiac events and renal failure. The certainty of the evidence validating this finding varied from moderate to very low, depending on the outcome. Future trials should focus on assessing the impact of statin therapy on mortality and major adverse cardiovascular events.

Early outcomes of aortic valve replacement with Perceval PLUS sutureless valve: results of the prospective multicentric MANTRA study.

BACKGROUND: The aim of this study is to report the preliminary real-word clinical and hemodynamic performance from the MANTRA study in patients undergoing aortic valve replacement with Perceval PLUS sutureless valve. METHODS: MANTRA is an ongoing "umbrella" prospective, multi-center, international post-market study to collect real-life safety and performance data on Corcym devices (Corcym S.r.l, Saluggia, Italy). Clinical and echocardiographic outcomes were collected preoperatively, at discharge and at each follow up. KCCQ-12 and EQ-5D-5L quality of life questionnaires were collected preoperatively and at 30-days. RESULTS: A total of 328 patients underwent aortic valve replacement with Perceval PLUS in 29 International institutions. Patients were enrolled from July 2021 to October 2023 and enrollment is still ongoing. Mean age was 71.9 ± 6.4 years, mean EuroSCORE II was 2.9 ± 3.9. Minimally invasive approach was performed in 44.2% (145/328) of patients; concomitant procedures were done in 40.8% (134/328) of cases. Thirty-day mortality was 1.8% (6/328) and no re-interventions were reported. Pacemaker implant was required in 4.0% (13/328) of the patients. The assessment of the functional status demonstrated marked and stable improvement in NYHA class in most patients at 30-day follow-up, with significant increase of KCCQ-12 summary score (from 58.8 ± 23.0 to 71.8 ± 22.1, p < 0.0001) and EQ-5D-5L VAS score (from 64.5 ± 20.4 to 72.6 ± 17.5, p < 0.0001). Mean pressure gradient decreased from 46.2 ± 17.3 mmHg to 10.1 ± 4.7 mmHg at 30-day follow-up. Low or no incidence of moderate-to-severe paravalvular or central leak was reported. CONCLUSIONS: Preliminary results demonstrate good clinical outcomes and significant improvement of Quality of Life at 30-days, excellent early hemodynamic performance within patient implanted with Perceval PLUS. TRIAL REGISTRATION: The MANTRA study has been registered in ClinicalTrials.gov (NCT05002543, Initial release 26 July 2021).

Activated clotting time value as an independent predictor of postoperative bleeding and transfusion.

OBJECTIVES: Activated clotting time (ACT) is commonly used to monitor anticoagulation during cardiac surgeries. Final ACT values may be essential to predict postoperative bleeding and transfusions, although ideal values remain unknown. Our aim was to evaluate the utility of ACT as a predictor of postoperative bleeding and transfusion use. METHODS: Retrospective study (722 patients) submitted to surgery between July 2018-October 2021. We compared patients with final ACT < basal ACT and final ACT ≥ basal ACT and final ACT < 140 s with ≥140 s. Continuous variables were analysed with the Wilcoxon rank-sum test; categorical variables using Chi-square or Fisher's exact test. A linear mixed regression model was used to analyse bleeding in patients with final ACT < 140 and ≥140. Independent variables were analysed with binary logistic regression models to investigate their association with bleeding and transfusion. RESULTS: Patients with final ACT ≥ 140 s presented higher postoperative bleeding than final ACT < 140 s at 12 h (P = 0.006) and 24 h (**P = 0.004). Cardiopulmonary bypass (CPB) time [odds ratio (OR) 1.009, 1.002-1.015, 95% confidence interval (CI)] and masculine sex (OR 2.842,1.721-4.821, 95% CI) were significant predictors of bleeding. Patients with final ACT ≥ 140 s had higher risk of UT (OR 1.81, 1.13-2.89, 95% CI; P = 0.0104), compared to final ACT < 140 s. CPB time (OR 1.019,1.012-1.026, 95% CI) and final ACT (OR 1.021,1.010-1.032, 95% CI) were significant predictors of transfusion. Female sex was a predictor of use of transfusion, with a probability for use of 27.23% (21.84-33.39%, 95% CI) in elective surgeries, and 60.38% (37.65-79.36%, 95% CI) in urgent surgeries, higher than in males. CONCLUSIONS: Final ACT has a good predictive value for the use of transfusion. Final ACT ≥ 140 s correlates with higher risk of transfusion and increased bleeding. The risk of bleeding and transfusion is higher with longer periods of CPB. Males have a higher risk of bleeding, but females have a higher risk of transfusion.

The impact of cardiopulmonary bypass time on the Sequential Organ Failure Assessment score after cardiac surgery.

OBJECTIVES: Postoperative organ dysfunction is common after cardiac surgery, particularly when cardiopulmonary bypass (CPB) is used. The Sequential Organ Failure Assessment (SOFA) score is validated to predict morbidity and mortality in cardiac surgery. However, the impact of CPB duration on postoperative SOFA remains unclear. METHODS: This is a retrospective study. Categorical values are presented as percentages. The comparison of SOFA groups utilized the Kruskal-Wallis chi-squared test, complemented by ad hoc Dunn's test with Bonferroni correction. Multinomial logistics regressions were employed to evaluate the relationship between CPB time and SOFA. RESULTS: A total of 1032 patients were included. CPB time was independently associated with higher postoperative SOFA scores at 24 h. CPB time was significantly higher in patients with SOFA 4-5 (**P = 0.0022) or higher (***P < 0.001) when compared to SOFA 0-1. The percentage of patients with no/mild dysfunction decreased with longer periods of CPB, down to 0% for CPB time >180min (50% of the patients with >180m in of CPB presented SOFA ≥ 10). The same trend is observed for each of the SOFA variables, with higher impact in the cardiovascular and renal systems. Severe dysfunction occurs especially >200 min of CPB (cardiovascular system >100 min; other systems mainly >200 min). CONCLUSIONS: CPB time may predict the probability of postoperative SOFA categories. Patients with extended CPB durations exhibited higher SOFA scores (overall and for each variable) at 24 h, with higher proportion of moderate and severe dysfunction with increasing times of CPB.

Surgical aortic valve replacement in octogenarians: Single-center perioperative outcomes and five-year survival.

INTRODUCTION AND OBJECTIVES: Aortic stenosis is the most common valvular heart disease. The number of octogenarians proposed for intervention is growing due to increased lifespan. In this manuscript we aim to evaluate perioperative outcome and long-term survival after surgical aortic valve replacement (SAVR) in octogenarians, comparing patients with low surgical risk (EuroscoreII <4%) with intermediate-high risk (EuroscoreII ≥4%). METHODS: A retrospective observational single-center cohort study with 195 patients aged ≥80 years old, who underwent SAVR between 2017 and 2021, was conducted. Patients were divided into two groups according to EuroscoreII: (1) Low risk (EuroscoreII <4%) with intermediate-high risk (EuroscoreII ≥4%). Continuous variables are presented in median (IQR), analyzed using Wilcoxon rank sum test; categorical variables in percentages, analyzed using chi-squared test; and survival was analyzed by Kaplan-Meier, open cohort, and the log-rank test was performed. RESULTS: The overall median age was 82 (IQR 81-83), with 4.6% of the patients ≥85 years old. 23.6% of the patients presented EuroscoreII ≥4%. No complications were observed in 26.2%, with a significantly higher rate in intermediate-high risk patients. Postoperative need for hemodynamic support was the most frequent complication, followed by postoperative acute kidney injury and the use of blood products. Overall median ICU stay was three days (2-4) and hospital length of stay (LOS) six days (5-8). Patients with intermediate-high risk and those with complications had longer ICU LOS. At 12 months, overall survival was 96.4%, at three years 94.1% and 5 years 75.4%. Patients with low surgical risk had higher survival proportions up to 5 years. CONCLUSION: SAVR in patients ≥80 years is associated with low in-hospital mortality, although a significant proportion of patients develop complications. Long-term follow-up up to five years after surgery is acceptable in octogenarians with low surgical risk.

Conduction Disorders And Their Clinical Impact After Sutureless/Rapid Deployment Aortic Bioprosthesis.

INTRODUCTION: Aortic stenosis remains the number one heart valve pathology. The drive to improve the surgical outcomes brought to focus rapid deployment valves (RDV), which reduce aortic cross-clamping and cardio-pulmonary bypass (CPB) times. However, some centers have reported a higher rate of conduction abnormalities and permanent pacemaker (PPM) implantation. The aim of this study was to investigate the incidence of conduction abnormalities after aortic valve replacement with RDV, as well as its impact on immediate postoperative outcomes. METHODS: Retrospective analysis of associated conductions disorders and PPM implantation rates, as well as post-operative outcomes of all patients undergoing isolated aortic valve replacement between April 2014 and December 2019 with an RDV. Comparative analysis between the group with PPM implantation and the one with no PPM implantation. Patients with previous PPM implantation, reoperations and patients with missing pre or postoperative ECG data were excluded. RESULTS: We studied 201 patients. The majority of conduction abnormalities were left bundle branch block (54,0%). Twenty-six PPM were implanted (12,6%). Pre-operative characteristic between the groups were similar and little differences were found in regard to most complications. However, the PPM group showed significantly higher rates of stroke (7.7% vs 0.0%, p=0.016) and hemodynamic support for longer than 24 hours (60.0% vs 36.1%, p=0.028). From the multivariable analysis, preoperative right bundle branch block was the only independent risk factor associated with PPM. CONCLUSIONS: PPM implantation rates with RDV are relatively high and are associated with prolonged hospital and ICU stays, postoperative stroke rates and requirement of aminergic support. Their use should be made on a case-by-case basis taking into consideration the existence of preoperative conduction disorders, especially right bundle branch block.

The evolution of management of type B aortic dissection in a series of 100 consecutive cases in a tertiary center.

INTRODUCTION AND OBJECTIVES: Management of aortic dissection is rapidly evolving. The present study aims to assess paradigm shifts in type B aortic dissection (TBAD) treatment modalities and their outcomes according to clinical presentation and type of treatment. We also aim to assess the impact of endovascular technology in TBAD management in order to define organizational strategies to provide an integrated cardiovascular approach. METHODS: We performed a retrospective review with descriptive analysis of the last 100 consecutive patients with TBAD admitted to the Vascular Surgery Department of Centro Hospitalar Universitário Lisboa Norte over a 16-year period. Results were stratified according to treatment modality and stage of the disease. The study was further divided into two time periods, 2003-2010 and 2011-2019, respectively before and after the introduction of a dedicated endovascular program for aortic dissections. RESULTS: A total of 100 patients (83% male; mean age 60 years) were included, of whom 59 were admitted in the acute stage (50.8% with complicated dissections). The other 41 patients were admitted for chronic dissections, most of them for surgical treatment of aneurysmal degeneration. Temporal analysis demonstrated an increase in the number of patients operated for aortic dissection, mainly due to an increase in chronic patients (33.3% in 2003-2010 vs. 64.4% in 2011-2019) and a clear shift toward endovascular treatment from 2015 onward. Overall in-hospital mortality was 14% and was significantly higher in the chronic phase (acute 5.1% vs. chronic 26.8%; OR 5.30, 95% CI 1.71-16.39; p=0.003) and in patients with aneurysmal degeneration, regardless of the temporal phase. Only one death was recorded in the endovascular group. CONCLUSION: Management of TABD carried an overall mortality of 14% during a 16-year period, but the appropriate use of endovascular technology has substantially reduced in-hospital mortality.

Post-infarction ventricular septal defect surgery in Portugal.

INTRODUCTION AND OBJECTIVE: We performed a collective analysis of a dedicated national post-myocardial infarction ventricular septal defect (VSD) registry to further elucidate controversial areas of this clinical entity's surgical treatment. METHODS: A descriptive statistical analysis was carried out and cumulative survival using the Kaplan-Meier method and multivariate logistic regression of risk factors for 30-day mortality are presented. RESULTS: Median survival of the cohort (n=76) was 72 months (95% CI 4-144 months). Better cumulative survival was observed in patients who underwent VSD closure more than 10 days after myocardial infarction (log-rank p=0.036). Concomitant coronary artery bypass grafting (CABG), different closure techniques, location of the VSD, extracorporeal membrane oxygenation as bridge to closure, or intra-aortic balloon pump as bridge to closure showed no statistically significant differences at Kaplan-Meier analysis. Multivariate binary logistic regression for independent factors affecting status at 30 days showed a statistically significant effect of age (OR 1.08; 95% CI 1.01-1.15) and concomitant CABG (OR 0.23; 95% CI 0.06-0.90). CONCLUSIONS: Our results are comparable with previous reports regarding mortality, risk factors and concomitant procedures. Timing of surgery remains a controversial issue. Later closure seems to be advantageous, however, there is significant observational bias.

Internal Mammary Artery Skeletonization - Review Of Current Evidence.

Internal mammary artery (IMA) harvesting is a central part in coronary artery bypass grafting (CABG). The technique of harvesting the IMA - pedicled, skeletonized, or semi-skeletonized, may influence intra-operatory and postoperatory outcomes. We aim to review current evidence regarding the advantages and disadvantages of these techniques, and their performance in certain subsets of patients.

Ascending Aorta Sacular Aneurysm.

. A 83 year old woman with history of arterial hypertension, hypothyroidism, obesity, chronic renal insufficiency and incipient dementia was transferred to our hospital after complaints of chest pain. Investigation revealed a sacular ascending aortic aneurysm with the aneurysmal sac adjacent to the sternum. Due to her age, cognitive state and risk of sternal entry, she was refused for surgery. She was discharged after coronariography showed normal coronaries and other causes of chest pain were excluded. She is still alive and stable after 40 months, with no growth of aneurysm dimensions.

Sutureless bioprosthesis for aortic valve replacement: Surgical and clinical outcomes.

BACKGROUND: Aortic valve stenosis is the most common adult valve disease in industrialized countries. The aging population and the increase in comorbidities urge the development of safer alternatives to the current surgical treatment. Sutureless bioprosthesis has shown promising results, especially in complex procedures and in patients requiring concomitant surgeries. OBJECTIVES: Assess the clinical and hemodynamic performance, safety, and durability of the Perceval® prosthetic valve. METHODS: This single-center retrospective longitudinal cohort study collected data from all adult patients with aortic valve disease who underwent aortic valve replacement with a Perceval® prosthetic valve between February 2015 and October 2020. Of the 196 patients included (mean age 77.20 ± 5.08 years; 45.4% female; mean EuroSCORE II 2.91 ± 2.20%), the majority had aortic stenosis. RESULTS: Overall mean cross-clamp and cardiopulmonary bypass times were 33.31 ± 14.09 min and 45.55 ± 19.04 min, respectively. Mean intensive care unit and hospital stay were 3.32 ± 3.24 days and 7.70 ± 5.82 days, respectively. Procedural success was 98.99%, as two explants occurred. Four valves were reimplanted due to intraoperative misplacement. Mean transvalvular gradients were 7.82 ± 3.62 mmHg. Pacemaker implantation occurred in 12.8% of patients, new-onset atrial fibrillation in 21.9% and renal replacement support was necessary for 3.1%. Early mortality was 2.0%. We report no structural valve deterioration, strokes, or endocarditis, and one successfully treated valve thrombosis. CONCLUSIONS: Our study confirms the excellent clinical and hemodynamic performance and safety of a truly sutureless aortic valve, up to a 5-year follow-up. These results were consistent in isolated and concomitant interventions, solidifying this device as a viable option for the treatment of isolated aortic valve disease.

Role of Omega-6 Fatty Acid Metabolism in Cardiac Surgery Postoperative Bleeding Risk.

Cardiac surgery is frequently associated with significant postoperative bleeding. Platelet-dysfunction is the main cardiopulmonary bypass (CPB)-induced hemostatic defect. Not only the number of platelets decreases, but also the remaining are functionally impaired. Although lipid metabolism is crucial for platelet function, little is known regarding platelet metabolic changes associated with CPB-dysfunction. Our aim is to explore possible contribution of metabolic perturbations for platelet dysfunction after cardiac surgery. DESIGN: Prospective cohort study. SETTING: Tertiary academic cardiothoracic-surgery ICU. PATIENTS: Thirty-three patients submitted to elective surgical aortic valve replacement. INTERVENTIONS: Samples from patients were collected at three time points (preoperative, 6- and 24-hr postoperative). Untargeted metabolic analysis using high-performance liquid chromatography-tandem mass spectrometry was performed to compare patients with significant postoperative bleeding with patients without hemorrhage. Principal component analyses, Wilcoxon matched-pairs signed-rank tests, adjusted to FDR, and pairwise comparison were used to identify pathways of interest. Enrichment and pathway metabolomic complemented the analyses. MEASUREMENTS AND MAIN RESULTS: We identified a platelet-related signature based on an overrepresentation of changes in known fatty acid metabolism pathways involved in platelet function. We observed that arachidonic acid (AA) levels and other metabolites from the pathway were reduced at 6 and 24 hours, independently from antiagreggation therapy and platelet count. Concentrations of preoperative AA were inversely correlated with postoperative chest tube blood loss but were not correlated with platelet count in the preoperative, at 6 or at 24 hours. Patients with significant postoperative blood-loss had considerably lower values of AA and higher transfusion rates. Values of postoperative interleukin-6 were strongly correlated with AA variability. CONCLUSIONS AND RELEVANCE: Our observations suggest that an inflammatory-related perturbation of AA metabolism is a signature of cardiac surgery with CPB and that preoperative levels of AA may be more relevant than platelet count to anticipate and prevent postoperative blood loss in patients submitted to cardiac surgery with CPB.

Surgical, anesthesical and perfusion strategies for open thoracoabdominal aneurysm repair.

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Sequential Organ Failure Assessment Score in the ICU As a Predictor of Long-Term Survival After Cardiac Surgery.

OBJECTIVES: The Sequential Organ Failure Assessment (SOFA) score is a predictor of mortality in ICU patients. Although it is widely used and has been validated as a reliable and independent predictor of mortality and morbidity in cardiac ICU, few studies correlate early postoperative SOFA with long-term survival. DESIGN: Retrospective observational cohort study. SETTING: Tertiary academic cardiac surgery ICU. PATIENTS: One-thousand three-hundred seventy-nine patients submitted to cardiac surgery. INTERVENTIONS: SOFA 24 hours, SOFA 48 hours, mean, and highest SOFA scores were correlated with survival at 12 and 24 months. Wilcoxon tests were used to analyze differences in variables. Multivariate logistic regressions and likelihood ratio test were used to access the predictive modeling. Receiver operating characteristic curves were used to assess accuracy of the variables in separating survivor from nonsurvivors. MEASUREMENTS AND MAIN RESULTS: Lower SOFA scores have better survival rates at 12 and 24 months. Highest SOFA and SOFA at 48 hours showed to be better predictors of outcome and to have higher accuracy in distinguishing survivors from nonsurvivors than initial SOFA and mean SOFA. A decreasing score during the first 48 hours had mortality rates of 4.9%, while an unchanged or increased score was associated with a mortality rate of 5.7%. CONCLUSIONS: SOFA score in the ICU after cardiac surgery correlated with survival at 12 and 24 months. Patients with lower SOFA scores had higher survival rates. Differences in survival at 12 months were better correlated with the absolute value at 48 hours than with its variation. SOFA score may be useful to predict long-term outcomes and to stratify patients with higher probability of mortality.

Bioprosthetic Aortic Valve Degeneration: a Review from a Basic Science Perspective

Abstract Introduction: The increase in the prevalence of aortic stenosis due to an aging population has led to an increasing number of surgical aortic valve replacements. Over the past 20 years, there has been a major shift in preference from mechanical to bioprosthetic valves. However, despite efforts, there is still no "ideal" bioprosthesis. It is crucial to understand the structure, biology, and function of native heart valves to design more intelligent, strong, durable, and physiological heart valve tissues. Methods: A comprehensive review of the literature was performed to identify articles reporting the basic mechanisms of bioprosthetic valve dysfunction and the biology of native valve cells. Searches were run in PubMed, MEDLINE® (the Medical Literature Analysis and Retrieval System Online), and Google Scholar. Terms for subject heading and keywords search included "biological heart valve dysfunction", "bioprosthesis dysfunction", "bioprosthesis degeneration", and "tissue heart valves". Results: All the relevant findings are summarized in the appropriate subsections. Structural dysfunction is a logical and expected consequence of the chemical, mechanical, and immunological processes that occur during fixation, manufacture, and implantation. Conclusion: Biological prosthesis valve dysfunction is a clinically significant process. It has become a major issue considering the growing rate of bioprosthesis implantation and improved long-term patient survival. Understanding bioprosthetic aortic valve degeneration from a basic science perspective is a key point to improve technologic advances and specifications that lead to a new generation of bioprostheses.

Bioprosthetic Aortic Valve Degeneration: a Review from a Basic Science Perspective.

INTRODUCTION: The increase in the prevalence of aortic stenosis due to an aging population has led to an increasing number of surgical aortic valve replacements. Over the past 20 years, there has been a major shift in preference from mechanical to bioprosthetic valves. However, despite efforts, there is still no "ideal" bioprosthesis. It is crucial to understand the structure, biology, and function of native heart valves to design more intelligent, strong, durable, and physiological heart valve tissues. METHODS: A comprehensive review of the literature was performed to identify articles reporting the basic mechanisms of bioprosthetic valve dysfunction and the biology of native valve cells. Searches were run in PubMed, MEDLINE® (the Medical Literature Analysis and Retrieval System Online), and Google Scholar. Terms for subject heading and keywords search included "biological heart valve dysfunction", "bioprosthesis dysfunction", "bioprosthesis degeneration", and "tissue heart valves". RESULTS: All the relevant findings are summarized in the appropriate subsections. Structural dysfunction is a logical and expected consequence of the chemical, mechanical, and immunological processes that occur during fixation, manufacture, and implantation. CONCLUSION: Biological prosthesis valve dysfunction is a clinically significant process. It has become a major issue considering the growing rate of bioprosthesis implantation and improved long-term patient survival. Understanding bioprosthetic aortic valve degeneration from a basic science perspective is a key point to improve technologic advances and specifications that lead to a new generation of bioprostheses.

Low Mean Arterial Pressure During Cardiopulmonary Bypass and the Risk of Acute Kidney Injury: A Propensity Score Matched Observational Study.

INTRODUCTION: Low mean arterial pressure (MAP) periods occur frequently during cardiopulmonary bypass (CPB), and their management remains controversial. Our aim was to correlate MAP during CPB with the occurrence of post-operative acute kidney injury (AKI), considering two different parameters: consecutive and cumulative low MAP periods. METHODS: Single-centre observational retrospective study including 250 patients submitted to non-emergent aortic valve replacement, with tepid to mild hypothermia (not below 32°C). The primary outcome was the occurrence of AKI. A propensity scored matching of 43 patients was used to adjust both populations (AKI and No AKI). MAP measures were automatically and continuously recorded during CPB. Low MAP periods were analysed employing two parameters: consecutive and the cumulative sum of time. RESULTS: Patients who experienced at least 5 min with MAP <50 mmHg had an increased risk of post-operative AKI (OR infinity; 95% CI, 1.47 to infinity; P = .026). The risk is also significant with MAP <40 mmHg (OR 2.78; 95% CI 1.1-6.9; = .044) and <30 mmHg (OR 3.36; 95% CI 1.2-9.2; P = .029). Post-operative AKI was associated with cumulative and consecutive periods of low MAP. Patients with periods of low MAP had higher levels of post-operative creatinine and reduced glomerular filtration rate (GFR). Patients with AKI had prolonged endotracheal ventilation time, and ICU and ward lengths of stay. CONCLUSION: Low MAP periods during CPB are associated with an increased occurrence of post-operative AKI, leading to 1) higher creatinine levels; 2) decreased GFR and 3) longer ICU and ward lengths of stay. Both consecutive and cumulative periods of low MAP are associated with an increased risk of AKI. MAP appears to be an important contributor to post-operative AKI and should be carefully managed during CPB. Further studies must address if MAP variations lead to definitive and long-term consequences.

An Incident of a Massive Pulmonary Embolism Following Acute Aortic Dissection. a Case Report.

Acute aortic dissection and acute pulmonary embolism are two life-threatening emergencies. The presented case is of an 81-year-old man who has been diagnosed with an acute Stanford type A aortic dissection and referred to a tertiary hospital for surgical treatment. After a successful aortic repair and an overall favourable postoperative recovery, he was diagnosed with cervical and upper extremity deep vein thrombosis and was anticoagulated accordingly. He later presented with massive bilateral pulmonary embolism.