Identifying Eukaryotes and Factors Influencing Their Biogeography in Drinking Water Metagenomes.

The biogeography of eukaryotes in drinking water systems is poorly understood relative to that of prokaryotes or viruses, limiting the understanding of their role and management. A challenge with studying complex eukaryotic communities is that metagenomic analysis workflows are currently not as mature as those that focus on prokaryotes or viruses. In this study, we benchmarked different strategies to recover eukaryotic sequences and genomes from metagenomic data and applied the best-performing workflow to explore the factors affecting the relative abundance and diversity of eukaryotic communities in drinking water distribution systems (DWDSs). We developed an ensemble approach exploiting k-mer- and reference-based strategies to improve eukaryotic sequence identification and identified MetaBAT2 as the best-performing binning approach for their clustering. Applying this workflow to the DWDS metagenomes showed that eukaryotic sequences typically constituted small proportions (i.e., <1%) of the overall metagenomic data with higher relative abundances in surface water-fed or chlorinated systems with high residuals. The α and ß diversities of eukaryotes were correlated with those of prokaryotic and viral communities, highlighting the common role of environmental/management factors. Finally, a co-occurrence analysis highlighted clusters of eukaryotes whose members' presence and abundance in DWDSs were affected by disinfection strategies, climate conditions, and source water types.

Gradual Recovery of Building Plumbing-Associated Microbial Communities after Extended Periods of Altered Water Demand during the COVID-19 Pandemic.

COVID-19 pandemic-related building restrictions heightened drinking water microbiological safety concerns post-reopening due to the unprecedented nature of commercial building closures. Starting with phased reopening (i.e., June 2020), we sampled drinking water for 6 months from three commercial buildings with reduced water usage and four occupied residential households. Samples were analyzed using flow cytometry and full-length 16S rRNA gene sequencing along with comprehensive water chemistry characterization. Prolonged building closures resulted in 10-fold higher microbial cell counts in the commercial buildings [(2.95 ± 3.67) × 105 cells mL-1] than in residential households [(1.11 ± 0.58) × 104 cells mL-1] with majority intact cells. While flushing reduced cell counts and increased disinfection residuals, microbial communities in commercial buildings remained distinct from those in residential households on the basis of flow cytometric fingerprinting [Bray-Curtis dissimilarity (dBC) = 0.33 ± 0.07] and 16S rRNA gene sequencing (dBC = 0.72 ± 0.20). An increase in water demand post-reopening resulted in gradual convergence in microbial communities in water samples collected from commercial buildings and residential households. Overall, we find that the gradual recovery of water demand played a key role in the recovery of building plumbing-associated microbial communities as compared to short-term flushing after extended periods of reduced water demand.

Gender and the Outcome of Postcardiotomy Veno-arterial Extracorporeal Membrane Oxygenation.

OBJECTIVE: There is a paucity of sex-specific data on patients' postcardiotomy venoarterial extracorporeal membrane oxygenation (VA-ECMO). The present study sought to assess this issue in a multicenter study. DESIGN: Retrospective, propensity score-matched analysis of an international registry. SETTING: Multicenter study, tertiary university hospitals. PARTICIPANTS: Data on adult patients undergoing postcardiotomy VA-ECMO. MEASUREMENTS AND MAIN RESULTS: Between January 2010 and March 2018, patients treated with postcardiotomy VA-ECMO at 17 cardiac surgery centers were analyzed. Index procedures considered were coronary artery bypass graft surgery, isolated valve surgery, their combination, and proximal aortic root surgery. Hospital and five-year mortality constituted the endpoints of interest. Propensity score matching was adopted with logistic regression. A total of 358 patients (mean age: 63.3 ± 12.3 years; 29.6% female) were identified. Among 94 propensity score-matched pairs, women had a higher hospital mortality (70.5% v 56.4%, p = 0.049) compared with men. Logistic regression analysis showed that women (odds ratio [OR], 1.87; 95% confidence interval [CI] 1.10-3.16), age (OR, 1.06; 95%CI 1.04-1.08) and pre-ECMO arterial lactate (OR, 1.09; 95%CI 1.04-1.16) were independent predictors of hospital mortality. No differences between female and male patients were observed for other outcomes. Among propensity score-matched pairs, one-, three-, and five-year mortality were 60.6%, 65.0%, and 65.0% among men, and 71.3%, 71.3%, and 74.0% among women, respectively (p = 0.110, adjusted hazard ratio, 1.27; 95%CI 0.96-1.66). CONCLUSIONS: In postcardiotomy VA-ECMO, female patients demonstrated higher hospital mortality than men. Morbidity and late mortality were similar between the two groups.

Outcome of Repeat Venoarterial Extracorporeal Membrane Oxygenation in Postcardiotomy Cardiogenic Shock.

OBJECTIVE: Data on patients requiring a second run of venoarterial extracorporeal membrane oxygenation (VA-ECMO) support in patients affected by postcardiotomy cardiogenic shock (PCS) are very limited. The authors aimed to investigate the effect of a second run of VA-ECMO on PCS patient survival. DESIGN: Retrospective analysis of an international registry. SETTING: Multicenter study, tertiary university hospitals. PARTICIPANTS: Data on adult PCS patients receiving a second run of VA-ECMO. MEASUREMENTS AND MAIN RESULTS: A total of 674 patients with a mean age of 62.9 ± 12.7 years were analyzed, and 21 (3.1%) patients had a second run of VA-ECMO. None of them required more than two VA-ECMO runs. The median duration of VA-ECMO therapy was 135 hours (interquartile range [IQR] 61-226) in patients who did not require a VA-ECMO rerun. In the rerun VA-ECMO group the median overall duration of VA-ECMO therapy was 183 hours (IQR 107-344), and the median duration of the first run was 114 hours (IQR 66-169). Nine (42.9%) of the patients who required a second run of VA-ECMO died during VA-ECMO therapy, whereas five (23.8%) survived to hospital discharge. No differences between patients treated with single or second VA-ECMO runs were observed in terms of hospital mortality and late survival. In patients requiring a second VA-ECMO run, the actuarial survival estimates at three and 12 months after VA-ECMO weaning were 23.8% ± 9.3% and 19.6% ± 6.4%, respectively. CONCLUSIONS: Repeat VA-ECMO therapy is a valid treatment strategy for PCS patients. Early and late survivals are similar between patients who have undergone a single or second run of VA-ECMO.

Bacterial dynamics in drinking water distribution systems and flow cytometry monitoring scheme optimization.

Water biostability is desired within drinking water distribution systems (DWDSs) to limit microbiologically-related operational, aesthetic and, eventually, health-related issues. However, variations in microbiological quality can take place both spatially along DWDS pipelines and temporally at single locations due to biofilm detachment, water quality seasonality and other processes. In this study, long- and short-term trends of bacterial concentration and community structure were investigated in a secondary branch of an unchlorinated DWDS for several months using high-frequency flow cytometry (FCM) and traditional laboratory monitoring campaigns. Long-term trends of bacterial concentrations and community structures were likely caused by changes in the water physical-chemical quality (i.e. pH and conductivity). Short-term daily pattern, instead, resulted in significant variations between the bacterial concentrations and community structures at different hours, likely due to biofilm detachment and loose deposits resuspension related to changes in the local water flow. These patterns, however, showed broad variations and did not persist during the entire monitoring campaign presumably due to the stochasticity of local instantaneous demand and seasonal changes in water consumption. During periods without sensible long-term trends, the sampling hours explain a comparable or larger fraction of the bacterial community diversity compared to dates. The variations observed with FCM were poorly or not detected by traditional laboratory analyses, as the correlation between the two were rather weak, highlighting the limited information provided by traditional approaches. On the other hand, FCM data correlated with water pH and conductivity, underlining the relation between physical-chemical and microbiological water quality. Such results suggest that the advanced control of the physical-chemical water quality could minimize the microbiological water quality variations. Moreover, monitoring campaign planning should take into account the sampling time to reduce the noise caused by daily fluctuations and/or assess the overall quality variations. Finally, as monitoring costs are one of the barriers which prevent a more widespread use of FCM, a monitoring scheme optimization strategy was developed. Such strategy employs the data from an initial high-frequency sampling period to select the sampling hours which maximize the observed variations of bacterial concentration and community composition.

Mycobacterium chimaera infections: An update.

Mycobacterium chimaera is a non-tuberculous mycobacterium belonging to the Mycobacterium avium complex, described for the first time in 2004. It acts as an opportunistic pathogen, with infections, usually respiratory illnesses, occurring more frequently in immunocompromised patients or in patients with underlying respiratory diseases. During the last decade Mycobacterium chimaera disseminated infections following cardiothoracic surgery, especially open-heart surgery, have been increasingly reported worldwide. From a pathogenic standpoint, Mycobacterium chimaera is acquired during cardiopulmonary bypass via bioaerosols emitted from contaminated heater-cooler units water systems. Due to non-specific symptoms and long latency, postoperative Mycobacterium chimaera infections may not be promptly diagnosed and treated, and may become life-threatening. The indication for revision surgery needs to be carefully evaluated on a case-by-case basis, and antibiotic therapy should be based on drug susceptibility testing results. Our review aims to provide an updated account of microbiological characteristics, clinical presentation, diagnosis, and management of Mycobacterium chimaera infections, with a special focus on those developing after cardiothoracic surgery.

Safe cross-clamp time using Custodiol®-histidine-tryptophan-ketoglutarate cardioplegia in the adult.

INTRODUCTION: Safe cross-clamp time using single-dose Custodiol®-histidine-tryptophan-ketoglutarate cardioplegia has not been established conclusively. METHODS: Immediate post-operative outcomes of 1,420 non-consecutive, cardiac surgery patients were reviewed retrospectively. Predictors of a combined endpoint made of in-hospital mortality and any major complication post-surgery were found with the multivariable method. Analysis of variance was used to evaluate the impact of cross-clamp time on most relevant complications. Discriminatory power and cut-off value of cross-clamp time were established for in-hospital mortality and each of the major complications (receiver operating characteristic curve analysis). A comparative analysis (with propensity matching) with multidose cold blood cardioplegia on in-hospital mortality post-surgery was performed in non-coronary surgery patients. RESULTS: Coronary, aortic valve and mitral valve surgery and surgery on thoracic aorta were performed in 45.4%, 41.9%, 49.5%, 20.6% of cases, respectively. In-hospital mortality and the rate of any major complication post-surgery were 6.5% and 41.9%, respectively. Cross-clamp time had significant impact on in-hospital mortality and almost all major post-operative complications, except neurological dysfunctions (p = 0.084), myocardial infarction (p = 0.12) and mesenteric ischaemia (p = 0.85). Areas under the receiver operating characteristic curve and the optimal cut-off values for in-hospital mortality and any major complication were of 0.657, 0.594, >140 and >127 minutes, respectively. Comorbidities-adjusted odds ratio for any major complication of cross-clamp time <127 minutes was 1.86 (p < 0.0001). Despite similar in-hospital mortality (p = 0.57), there was an earlier significant increase of mortality in Custodiol-HTK than in multidose cold blood propensity-matched, non-coronary surgery patients. CONCLUSIONS: The use of Custodiol-HTK cardioplegia is associated with a low risk of serious post-operative complications provided that cross-clamp time is of 2 hours or less.

The Risk of Neurological Dysfunctions after Deep Hypothermic Circulatory Arrest with Retrograde Cerebral Perfusion.

OBJECTIVE: Retrograde cerebral perfusion (RCP) is a brain protection technique that is adopted generally for anticipated short periods of deep hypothermic circulatory arrest (DHCA). However, the real impact of this technique on cerebral protection during DHCA remains a controversial issue. METHODS: For 344 (59.5%) of 578 consecutive patients (mean age, 66.9 ± 10.9 years) who underwent cardiovascular surgery under DHCA at the present authors' institution (1999-2015), RCP was the sole technique of cerebral protection that was adopted in addition to deep hypothermia. Surgery of the thoracic aorta was performed in 95.9% of these RCP patients; in 92 cases there was an aortic arch involvement. Outcomes were reviewed retrospectively. The focus was on postoperative neurological dysfunctions. RESULTS: There were 33 (9.6%) in-hospital deaths. Thirty-one (9%) patients had permanent neurological dysfunctions and 66 (19.1%) transitory neurological dysfunctions alone. Age older than 74 years (odds ratio [OR], 1.88, P = .023), surgery for acute aortic dissection (OR, 2.57; P = .0009), and DHCA time longer than 25 minutes (OR, 2.44; P = .0021) were predictors of neurological dysfunctions. The 10-year nonparametric estimate of freedom from all-cause death was 61.8% (95% confidence interval, 57.8%-65.8%). Permanent postoperative neurological dysfunctions were risk factors for cardiac or cerebrovascular death (hazard ratio, 2.6; P = .039) even after an adjusted survival analysis (P < .04). CONCLUSIONS: According to the study findings, RCP, in addition to deep hypothermia, combines with a low risk of neurological dysfunctions provided that DHCA length is 25 minutes or less. Permanent postoperative neurological dysfunctions are predictors of poor late survival.

Bilateral internal thoracic artery grafting in octogenarians: where are the benefits?

The use of bilateral internal thoracic artery (BITA) grafting for myocardial revascularization is usually discouraged in the very elderly because of increased risk of perioperative complications. The aim of the study was to analyze early and late outcomes of BITA grafting in octogenarians. From January 1999 throughout February 2014, 236 consecutive octogenarians with multivessel coronary artery disease underwent primary isolated coronary bypass surgery at the authors' institution. Six of these patients underwent emergency surgery and were excluded from this retrospective study; consequently, 135 BITA patients were compared with 95 single internal thoracic artery (SITA) patients according to early and late outcomes. Between BITA and SITA patients, there was no significant difference in the operative risk (EuroSCORE II: 8 ± 7.7 vs. 7.6 ± 6.1 %, p = 0.65). There was a lower aortic manipulation in BITA patients. Hospital mortality (3 vs. 4.2 %, p = 0.44) and perioperative complications were similar except that only BITA patients experienced sternal wound infection (5.2 %, p = 0.022). The mean follow-up was 4.7 ± 3.3 years. There were no differences between the two groups in overall survival (p = 0.79), freedom from cardiac and cerebrovascular deaths (p = 0.73), major adverse cardiac and cerebrovascular events (p = 0.63) and heart failure hospital readmission (p = 0.64). Predictors of decreased late survival were diabetes (p = 0.0062) and congestive heart failure (p = 0.0004). BITA grafting can be routinely used in octogenarians with atherosclerotic ascending aorta without an increase in hospital mortality or major adverse cardiac and cerebrovascular complications. However, there is an increased risk of sternal wound infection without a demonstrable long-term benefit.

The impact of DNA extraction on the quantification of Legionella, with implications for ecological studies.

Monitoring the levels of opportunistic pathogens in drinking water is important to plan interventions and understand the ecological niches that allow them to proliferate. Quantitative PCR is an established alternative to culture methods that can provide a faster, higher-throughput, and more precise enumeration of the bacteria in water samples. However, PCR-based methods are still not routinely applied for Legionella monitoring, and techniques, such as DNA extraction, differ notably between laboratories. Here, we quantify the impact that DNA extraction methods had on downstream PCR quantification and community sequencing. Through a community science campaign, we collected 50 water samples and corresponding shower hoses, and compared two commonly used DNA extraction methodologies to the same biofilm and water phase samples. The two methods showed clearly different extraction efficacies, which were reflected in both the quantity of DNA extracted and the concentrations of Legionella enumerated in both the matrices. Notably, one method resulted in higher enumeration in nearly all samples by about one order of magnitude and detected Legionella in 21 samples that remained undetected by the other method. 16S rRNA amplicon sequencing revealed that the relative abundance of individual taxa, including sequence variants of Legionella, significantly varied depending on the extraction method employed. Given the implications of these findings, we advocate for improvement in documentation of the performance of DNA extraction methods used in drinking water to detect and quantify Legionella, and characterize the associated microbial community.IMPORTANCEMonitoring for the presence of the waterborne opportunistic pathogen Legionella is important to assess the risk of infection and plan remediation actions. While monitoring is traditionally carried on through cultivation, there is an ever-increasing demand for rapid and high-throughput molecular-based approaches for Legionella detection. This paper provides valuable insights on how DNA extraction affects downstream molecular analysis such as the quantification of Legionella through droplet digital PCR and the characterization of natural microbial communities through sequencing analysis. We analyze the results from a risk-assessment, legislative, and ecological perspective, showing how initial DNA processing is an important step to take into account when shifting to molecular-based routine monitoring and discuss the central role of consistent and detailed reporting of the methods used.

An integrated human health risk assessment framework for alkylphenols due to drinking water and crops' food consumption.

The increasing overexploitation and pollution of freshater resources are potential threats for public health, causing cross-contamination among the interconnected environmental compartments (freshwater, soil, crops). In particular, contaminants of emerging concern (CECs) originating from anthropic activities are not completely removed by wastewater treatments plants. This leads to their presence in drinking water (DW) sources, soil and crops intended for human consumption due to discharges of treated wastewater in surface waters and direct wastewater reuse practices. Currently, health risk assessments are limited to single exposure sources without considering the multiple exposure routes to which humans are subjected. For instance, among CECs, bisphenol A (BPA) and nonylphenol (NP), respectively, adversely affect immune and renal systems and have been frequently detected in DW and food, their major exposure sources for humans. Here, an integrated procedure is proposed to quantitatively assess health risk from CECs due to multiple exposure from the consumption of both DW and food, considering the relevant inter-connected environmental compartments. This procedure was applied to BPA and NP to calculate their probabilistic Benchmark Quotient (BQ), showing its potential in quantitatively apportioning the risk between contaminants and exposure sources, and its use as a decision support tool for prioritizing mitigation measures. Our results indicate that, even though the human health risk due to NP is not negligible, the estimated risk due to BPA is significantly higher, and the consumption of food from edible crops determines a higher risk compared to tap water. Hence, BPA is undoubtedly a contaminant to be prioritized, especially through mitigation actions aimed at its prevention and removal from food.

Modelling and prediction of the effect of operational parameters on the fate of contaminants of emerging concern in WWTPs.

Wastewater treatment plants (WWTPs) provide a barrier against the discharge of contaminants of emerging concern (CECs) into the environment. The removal of CECs is highly WWTP-specific and the underlying mechanisms are still poorly understood, hampering the optimization of biological treatment steps for their removal. To fill this knowledge gap, we assessed the influence of four operational parameters of activated sludge biological treatment, namely total suspended solids, temperature, pH and redox conditions, on the sorption and biodegradation of four CECs under controlled laboratory conditions. Design of Experiments was used to better address the factors influencing CECs removal and interactions among operational parameters. The derived statistical models showed results in concordance with previous studies and indicated how sorption and biodegradation of the investigated CECs depend on most tested parameters and few of their interactions. The predictions of the developed models have been compared with literature values, indicating how the tested parameters are responsible for most of the variability of sorption, while they could not reliably generalize biodegradation rates. The developed models were also implemented as an extension of a mechanistic biological treatment model, successfully describing the dynamic behaviour of a large-scale WWTP, which was observed during a three-day continuous monitoring campaign. Compared to a traditional modelling approach, the one including the developed models showed on average almost a three-fold uncertainty reduction, favouring its use to aid WWTP managers and regulators for improved assessment of CEC fate and removal. Finally, the models highlighted that, while higher temperatures and solids concentrations generically favoured CECs removal, removal efficiency vary significantly due to operational parameters and no globally optimum conditions for CECs removal exist. The use of these models opens the door to the combined dynamic management of both traditional contaminants and CECs in WWTPs.

Pica (Allotriophagy): An Underestimated Risk Factor for Severe Leptospirosis (Weil's Diseases)? Report of a Leptospira Septic Shock Successfully Managed with ECMO.

Leptospirosis is a zoonosis caused by infection with pathogenic strains of the bacterium Leptospira. The disease can be complicated by pulmonary hemorrhages and acute respiratory distress syndrome, with the mortality rate increasing to 51-100%. We report the case of a 37-year-old man who was admitted to the emergency department with a 6-day history of fever, weakness, vomiting and diarrhea, followed by jaundice. On admission, he presented leukocytosis, thrombocytopenia and acute liver and kidney injuries. His clinical course was critical, as it was immediately complicated by sepsis and severe respiratory failure, requiring haemodialysis, mechanical ventilation and broad-spectrum antibiotic therapy. In the following days, a veno-venous extracorporeal membrane oxygenation (VV-ECMO) was started due to a dramatic deterioration in respiratory function; 20 h later, it was switched to veno-arterial ECMO because of refractory cardiogenic shock. Hantavirus or Leptospira infection etiology was suspected, so penicillin G and methylprednisolone were initiated as an empirical therapy and subsequently confirmed after a laboratory diagnosis of leptospirosis. Although the clinical course was further complicated by hemorrhagic pneumonia, a gradual, full recovery occurred, and the patient was discharged from the hospital. After excluding other sources of contact with Leptospira-infected material, an unsuspected abnormal eating behavior was identified as the most probable cause of the patient's Leptospira infection.

Risk assessment of contaminants of emerging concern in the context of wastewater reuse for irrigation: An integrated modelling approach.

Direct reuse of reclaimed wastewater (RWW) in agriculture has recently received increasing attention as a possible solution to water scarcity. The presence of contaminants of emerging concern (CECs) in RWW can be critical, as these chemicals can be uptaken in irrigated crops and eventually ingested during food consumption. In the present study, an integrated model was developed to predict the fate of CECs in water reuse systems where RWW is used for edible crops irrigation. The model was applied to a case study where RWW (originating from a municipal wastewater treatment plant) is discharged into a water channel, with subsequent irrigation of silage maize, rice, wheat and ryegrass. Environmental and human health risks were assessed for 13 CECs, selected based on their chemical and hazard characteristics. Predicted CEC concentrations in the channel showed good agreement with available measurements, indicating potential ecotoxicity of some CECs (estrogens and biocides) due to their limited attenuation. Plant uptake predictions were in good agreement with existing literature data, indicating higher uptake in leaves and roots than fruits. Notably, high uncertainties were shown for weakly acidic CECs, possibly due to degradation in soil and pH variations inside plants. The human health risk due to the ingestion of wheat and rice was assessed using the threshold of toxicological concern and the hazard quotient. Both approaches predicted negligible risk for most CECs, while sulfamethoxazole and 17α-ethinylestradiol exhibited the highest risk for consumers. Alternative scenarios were evaluated to identify possible risk minimization strategies (e.g., adoption of a more efficient irrigation system).

Postcardiotomy Venoarterial Extracorporeal Membrane Oxygenation in Patients Aged 70 Years or Older.

BACKGROUND: There is uncertainty whether venoarterial extracorporeal membrane oxygenation (VA-ECMO) should be used in older patients with cardiopulmonary failure after cardiac surgery. METHODS: This was a retrospective multicenter study of 781 patients who required postcardiotomy VA-ECMO for cardiopulmonary failure after adult cardiac surgery from 2010 to 2018 at 19 cardiac surgery centers. A parallel systematic review with meta-analysis of the literature was performed. RESULTS: The hospital mortality in the overall Postcardiotomy Venoarterial Extracorporeal Membrane Oxygenation (PC-ECMO) series was 64.4%. A total of 255 patients were 70 years old or older (32.7%), and their hospital mortality was significantly higher than in younger patients (76.1% vs 58.7%; adjusted odds ratio, 2.199; 95% confidence interval [CI], 1.536 to 3.149). Arterial lactate level greater than 6 mmol/L before starting VA-ECMO was the only predictor of hospital mortality among patients 70 years old or older in univariate analysis (82.6% vs 70.4%; P = .029). Meta-analysis of current and previous studies showed that early mortality after postcardiotomy VA-ECMO was significantly higher in patients aged 70 years or older compared with younger patients (odds ratio, 2.09; 95% CI, 1.59 to 2.75; 5 studies including 1547 patients; I2, 5.9%). The pooled early mortality rate among patients aged 70 years or older was 78.8% (95% CI, 74.1 to 83.5; 6 studies including 617 patients; I2, 41.8%). Two studies reported 1-year mortality (including hospital mortality) of 79.9% and 75.6%, respectively, in patients 70 years old or older. CONCLUSIONS: Advanced age should not be considered a contraindication for postcardiotomy VA-ECMO. However, in view of the high risk of early mortality, meaningful scrutiny is needed before using VA-ECMO after cardiac surgery in older patients.

Diagnosis and management of severe atherosclerosis of the ascending aorta and aortic arch during cardiac surgery: focus on aortic replacement.

OBJECTIVE: Severe atherosclerosis of the ascending aorta and arch frequently causes difficulties during heart operations, hindering surgical manoeuvres and potentially leading to systemic embolism. The aim of our study was to assess the safety and effectiveness of replacing the atherosclerotic ascending aorta in this setting. METHODS: Aortic atherosclerosis was characterized by epiaortic ultrasonographic scanning in 90.1% of 1927 consecutive adult patients undergoing cardiac operations, and by computed tomographic chest scanning in selected cases. Thirty-six of the 152 patients requiring major derangements from our standard practice due to aortic atherosclerosis underwent replacement of the ascending aorta and constitute the study group. Replacement of the aorta was extended to the arch in 13 cases (36.1%). It was associated with single or multiple valve surgery in 34 patients (94.4%) and with coronary revascularization in 30 (83.3%). Two patients (5.6%) underwent coronary bypass grafting without valve surgery. A cryoablation procedure was associated in three patients with permanent atrial fibrillation. Deep hypothermic circulatory arrest was employed in 34 patients (94.4%), while proximal aortic disease allowed conventional distal crossclamping in 2 cases. The risk of operative mortality was estimated by the logistic EuroSCORE both with and withholding the variable "surgery of the thoracic aorta". All survivors were followed-up for 1-41 months (16+/-12). RESULTS: Two patients died in the hospital (5.6%) and two during follow-up, for a cumulative survival of 91.3% and 85.6% at 1 and 3 years, respectively (hospital deaths included). The hospital death rate compared favourably with the expected estimates of 25.5% (p<0.05) and 10.3% (p=0.67) obtained by the EuroSCORE full model and without "aortic surgery", respectively. In-hospital adverse neurologic events occurred in six patients (16.7%), including stroke in one patient (2.8%) and neurocognitive disturbances in five (13.9%), although they were all transient and cleared before discharge. Excess bleeding required re-exploration in four patients (11.1%), and one more patient underwent emergency grafting for acute postoperative coronary occlusion. Ten patients (38.5%) were intubated for longer than 24h. CONCLUSION: Despite significant perioperative morbidity, replacement of the severely atherosclerotic aorta is worth consideration to avert expectedly higher death and stroke rates.

Liberal bilateral internal thoracic artery use in people with diabetes neutralizes the negative impact of insulin-requiring status.

AIMS: Bilateral internal thoracic artery (BITA) grafts are underused in insulin-dependent diabetic patients because of increased risk of postoperative complications. The impact of the insulin-requiring status on outcomes after routine BITA grafting was investigated in this retrospective study. METHODS: Skeletonized BITA grafts were used in 3228 (71.6%) of 4508 consecutive patients having multivessel coronary disease who underwent isolated coronary bypass surgery at the authors' institution from January 1999 to August 2015. Among these BITA patients, diabetes mellitus and the insulin-requiring status were present in 972 (30.1%) and 237 (7.3%) cases, respectively. After the one-to-one propensity score-matching, 215 pairs of insulin-dependent/noninsulin-dependent people with diabetes were compared as the postoperative outcomes. The operative risk was calculated for each patient according to the logistic European System for Cardiac Operative Risk Evaluation (logistic EuroSCORE). RESULTS: As expected, insulin-dependent people with diabetes had higher risk profiles than noninsulin-dependent people with diabetes (median logistic EuroSCORE, 4.1 vs. 3.5%, P = 0.086). However, there were no differences in in-hospital mortality both in unmatched and propensity score-matched series (2.5 vs. 2%, P = 0.65 and 2.8 vs. 1.9%, P = 0.52, respectively). In propensity score-matched pairs, only prolonged invasive ventilation (P = 0.0039) and deep sternal wound infection (P = 0.071) were more frequent in insulin-dependent people with diabetes. No differences were found as the late outcomes. CONCLUSION: In diabetic patients, the insulin-requiring status is by itself a risk factor neither for in-hospital death nor for poor late outcomes after routine BITA grafting. Only the risk of prolonged invasive ventilation and deep sternal wound infection are increased early after surgery.

Venoarterial extracorporeal membrane oxygenation after coronary artery bypass grafting: Results of a multicenter study.

BACKGROUND: The evidence of the benefits of using venoarterial extracorporeal membrane oxygenation (VA-ECMO) after coronary artery bypass grafting (CABG) is scarce. METHODS: We analyzed the outcomes of patients who received VA-ECMO therapy due to cardiac or respiratory failure after isolated CABG in 12 centers between 2005 and 2016. Patients treated preoperatively with ECMO were excluded from this study. RESULTS: VA-ECMO was employed in 148 patients after CABG for median of 5.0days (mean, 6.4, SD 5.6days). In-hospital mortality was 64.2%. Pooled in-hospital mortality was 65.9% without significant heterogeneity between the centers (I2 8.6%). The proportion of VA-ECMO in each center did not affect in-hospital mortality (p=0.861). No patients underwent heart transplantation and six patients received a left ventricular assist device. Logistic regression showed that creatinine clearance (p=0.004, OR 0.98, 95% CI 0.97-0.99), pulmonary disease (p=0.018, OR 4.42, 95% CI 1.29-15.15) and pre-VA-ECMO blood lactate (p=0.015, OR 1.10, 95% CI 1.02-1.18) were independent baseline predictors of in-hospital mortality. One-, 2-, and 3-year survival was 31.0%, 27.9%, and 26.1%, respectively. CONCLUSIONS: One third of patients with need for VA-ECMO after CABG survive to discharge. In view of the burden of resources associated with VA-ECMO treatment and the limited number of patients surviving to discharge, further studies are needed to identify patients who may benefit the most from this treatment.

A predictive scoring system for deep sternal wound infection after bilateral internal thoracic artery grafting.

OBJECTIVES: Despite long-term survival benefits, the increased risk of sternal complications limits the use of bilateral internal thoracic artery (BITA) grafts for myocardial revascularization. The aim of the present study was both to analyse the risk factors for deep sternal wound infection (DSWI), which complicates routine BITA grafting and to create a DSWI risk score based on the results of this analysis. METHODS: BITA grafts were used as skeletonized conduits in 2936 (70.6%) of 4160 consecutive patients with multivessel coronary artery disease who underwent isolated coronary bypass surgery at the authors' institution from 1 January 1999 to 2013. The outcomes of these BITA patients were reviewed retrospectively and a risk factor analysis for DSWI was performed. RESULTS: A total of 129 (4.4%) patients suffered from DSWI. Two multivariable analysis models were created to examine preoperative factors either alone or combined with intraoperative and postoperative factors. Female gender, obesity, diabetes, poor glycaemic control, chronic lung disease and urgent surgical priority were the predictors of DSWI common to both models. Two (preoperative and combined) models of a new scoring system were devised to predict DSWI after BITA grafting. The preoperative model performed better than five of six scoring systems for sternal wound infection that were considered; the combined model performed better than three considered scoring systems. CONCLUSIONS: A weighted scoring system based on risk factors for DSWI was specifically created to predict DSWI risk after BITA grafting. This scoring system outperformed the existing scoring systems for sternal wound infection after coronary bypass surgery. Prospective studies are needed for validation.

[A quality improvement program in cardiac surgery. Four-year experience from the Ospedali Riuniti of Trieste]. / Un programma di miglioramento della qualità in cardiochirurgia. Quattro anni di esperienza agli Ospedali Riuniti di Trieste.

BACKGROUND: Dissatisfaction with clinical outcomes prompted an intervention to assess and improve processes and outcomes in a cardiac surgery unit. METHODS: Starting on September 1st, 1998, 1836 consecutive patients requiring a heart operation in our unit were prospectively enrolled by recording a series of anamnestic, clinical and procedural descriptors in a dedicated database. Expected mortality rates were estimated by means of nine different stratification models, one of which also allowed the prediction of excess intensive care unit and total hospital length of stay. Communication within the team has been re-engineered during the time frame studied. Some procedures have been modified and some others newly introduced according to a problem-oriented approach. RESULTS: One hundred and twenty-one patients died before discharge or within 30 days of the operation. The overall observed mortality rate (6.6%) was not significantly different from the predicted estimates (relative risk-RR 0.9, 95% confidence interval-CI 0.7-1.2 compared with EuroSCORE and RR 1.2, 95% CI 0.9-1.6 compared with the "Provincial Adult Cardiac Care Network" model). Two out of seven "dedicated" coronary surgery models predicted a mortality rate significantly lower than observed. Both rates of intensive care and total postoperative length of stay exceeding predefined thresholds turned out to be significantly higher than the predicted estimates: 14.3 vs 10.1% for intensive care (RR 1.4, 95% CI 1.2-1.7) and 13.6 vs 10.6% for total postoperative stay (RR 1.3, 95% CI 1.1-1.5). During the study period the yearly raw mortality rate gradually decreased, for the series as a whole, from 9.5% during the year 1999 to 4.1% during the year 2002, and for the coronary surgery sample from 6.5 to 2.1%, with no significant differences from the expected estimates over the 3 most recent years. A similar trend was noted for both intensive care unit and total hospital length of stay. CONCLUSIONS: Implementing an internal continuous quality improvement program effectively assisted in improving surgical outcomes by motivating people involved, drawing attention to procedures to be re-engineered and by providing the proper benchmarks for assessing the results.