Risk factors for surgical site infection following cardiac surgery in a region endemic for multidrug resistant organisms

OBJECTIVES

To identify risk factors for surgical site infections following cardiosurgery in an area endemic for multidrug resistant organisms.

DESIGN

Single-center, historical cohort study including patients who underwent cardiosurgery during a 6-year period (2014-2020).

SETTING

Joint Commission International accredited, multiorgan transplant center in Palermo, Italy.

MAIN OUTCOME MEASURES

Surgical site infection was the main outcome.

RESULTS

On a total of 3609 cardiosurgery patients, 184 developed surgical site infection (5.1 %). Intestinal colonization with multidrug resistant organisms was more frequent in patients with surgical site infections (69.6 % vs. 33.3 %; p < 0.001). About half of surgical site infections were caused by Gram-negative bacteria (n = 97; 52.7 %). Fifty surgical site infections were caused by multidrug resistant organisms (27.1 %), with extended-spectrum Beta-lactamase-producing Enterobacterales (n = 16; 8.7 %) and carbapenem-resistant Enterobacterales (n = 26; 14.1 %) being the predominant resistance problem. However, in only 24 of surgical site infections caused by multidrug resistant organisms (48 %), mostly carbapenem-resistant Enterobacterales (n = 22), a pathogen match between the rectal surveillance culture and surgical site infections clinical culture was demonstrated. Nevertheless, multivariate logistic regression analysis identified a rectal swab culture positive for multidrug resistant organisms as an independent risk factor for SSI (odds ratio 3.95, 95 % confidence interval 2.79-5.60). Other independent risk factors were female sex, chronic dialysis, diabetes mellitus, previous cardiosurgery, previous myocardial infarction, being overweight/obese, and longer intubation time.

CONCLUSION

In an area endemic for carbapenem-resistant Enterobacterales, intestinal colonization with multidrug resistant organisms was recognized as independent risk factor for surgical site infections.

IMPLICATIONS FOR CLINICAL PRACTICE

No causal relationship between colonization with resistant pathogens and subsequent infection could be demonstrated. However, from a broader epidemiological perspective, having a positive multidrug resistant organisms colonization status appeared a risk factor for surgical site infections. Therefore, strict infection control measures to prevent cross-transmission remain pivotal (e.g., nasal decolonization, hand hygiene, and skin antisepsis).

Regional biomechanical characterization of human ascending aortic aneurysms: Microstructure and biaxial mechanical response

The ascending thoracic aortic aneurysm (ATAA) is a permanent dilatation of the vessel with a high risk of adverse events, and shows heterogeneous properties. To investigate regional differences in the biomechanical properties of ATAAs, tissue samples were collected from 10 patients with tricuspid aortic valve phenotype and specimens from minor, anterior, major, and posterior regions were subjected to multi-ratio planar biaxial extension tests and second-harmonic generation (SHG) imaging. Using the data, parameters of a microstructure-motivated constitutive model were obtained considering fiber dispersion. SHG imaging showed disruptions in the organization of the layers. Structural and material parameters did not differ significantly between regions. The non-symmetric fiber dispersion model proposed by Holzapfel et al. [25] was used to fit the data. The mean angle of collagen fibers was negatively correlated between minor and anterior regions, and the parameter associated with collagen fiber stiffness was positively correlated between minor and major regions. Furthermore, correlations were found between the stiffness of the ground matrix and the mean fiber angle, and between the parameter associated with the collagen fiber stiffness and the out-of-plane dispersion parameter in the posterior and minor regions, respectively. The experimental data collected in this study contribute to the biomechanical data available in the literature on human ATAAs. Region-specific parameters for the constitutive models are fundamental to improve the current risk stratification strategies, which are mainly based on aortic size. Such investigations can facilitate the development of more advanced finite element models capable of capturing the regional heterogeneity of pathological tissues. STATEMENT OF SIGNIFICANCE: Tissue samples of human ascending thoracic aortic aneurysms (ATAA) were collected. Samples from four regions underwent multi-ratio planar biaxial extension tests and second-harmonic generation imaging. Region-specific parameters of a microstructure-motivated model considering fiber dispersion were obtained. Structural and material parameters did not differ significantly between regions, however, the mean fiber angle was negatively correlated between minor and anterior regions, and the parameter associated with collagen fiber stiffness was positively correlated between minor and major regions. Furthermore, correlations were found between the stiffness of the ground matrix and the mean fiber angle, and between the parameter associated with the collagen fiber stiffness and the out-of-plane dispersion parameter in the posterior and minor regions, respectively. This study provides a unique set of mechanical and structural data, supporting the microstructural influence on the tissue response. It may facilitate the development of better finite element models capable of capturing the regional tissue heterogeneity.

Cognitive outcomes in patients treated with neuromuscular electrical stimulation after coronary artery bypass grafting

Objective

Mechanisms of neurocognitive injury as post-operative sequelae of coronary artery bypass grafting (CABG) are not understood. The systemic inflammatory response to surgical stress causes skeletal muscle impairment, and this is also worsened by immobility. Since evidence supports a link between muscle vitality and neuroprotection, there is a need to understand the mechanisms by which promotion of muscle activity counteracts the deleterious effects of surgery on long-term cognition.

Methods

We performed a clinical trial to test the hypothesis that adding neuromuscular electrical stimulation (NMES) to standard rehabilitation care in post-CABG patients promotes the maintenance of skeletal muscle strength and the expression of circulating neuroprotective myokines.

Results

We did not find higher serum levels of neuroprotective myokines, except for interleukin-6, nor better long-term cognitive performance in our intervention group. However, a greater increase in functional connectivity at brain magnetic resonance was seen between seed regions within the default mode, frontoparietal, salience, and sensorimotor networks in the NMES group. Regardless of the treatment protocol, patients with a Klotho increase 3 months after hospital discharge compared to baseline Klotho values showed better scores in delayed memory tests.

Significance

We confirm the potential neuroprotective effect of Klotho in a clinical setting and for the first time post-CABG.

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.

Molecular Analysis With 16S rRNA PCR/Sanger Sequencing and Molecular Antibiogram Performed on DNA Extracted From Valve Improve Diagnosis and Targeted Therapy of Infective Endocarditis: A Prospective Study

BACKGROUND

Molecular analysis (MA) on heart valve (HV) improves the microbiologic diagnosis of infectious endocarditis (IE). The main drawback of MA is the lack of antimicrobial susceptibility information.

METHODS

We conducted a prospective cohort observational study of consecutive adult patients from April 2012 to May 2021 who underwent valve surgery at our hospital. The performance of MA, blood cultures (BC) and valve cultures (VC), and the diagnostic and therapeutic impact of MA were evaluated. Molecular antibiogram results were compared to culture-based antimicrobial susceptibility testing (AST).

RESULTS

A total of 137 patients with definite IE and 52 patients with no IE were enrolled in the study. Among IE cases BC, VC, and MA were positive in 75 (55%), 30 (22%), and 120 (88%) of IE cases, respectively. Among 62 cases of BC-negative IE (BCNE), 57 achieved diagnosis with MA. MA led to a change of antimicrobial therapy in 92% of BCNE. MA was negative in 100% of patients with no IE. Molecular antibiogram performed on 17 valve specimens that resulted positive for pathogens potential carrier of genes encoding for multidrug resistant mechanisms showed 100% concordance with AST.

CONCLUSIONS

MA showed a high specificity and sensitivity in etiological diagnosis of IE. Molecular antibiogram could overcome the major limitation of MA that is the lack of susceptibility testing. We advocate for the inclusion of MA among diagnostic criteria for IE and for a more extensive use of molecular antibiogram when the culture result is negative, and MA is the only positive test.

P291 SUBVALVULAR MITRAL APPARATUS REMODELING DURING HYPERTROPHIC OBSTRUCTIVE CARDIOMYOPATHY SURGERY: A 15–YEARS OF EXPERIENCE

Background and Aims

To assess the role of the mitral valve apparatus (leaflets, chordae and papillary muscles (PM) in left ventricle outflow tract (LVOT) obstruction, and results of the surgical treatment for hypertrophic obstructive cardiomyopathy (HOCM) in a retrospective observational study.

Methods

Seventy consecutive patients (58±12 years, M/F ratio: 41/29) undergoing HOCM surgery from 2007 to 2021 at our institute were reviewed. End points included the involvement of the mitral valve in LVOT obstruction, mortality, and change in clinical and echocardiographic characteristics after HOCM surgery.

Results

Secondary chordae tendineae tractioning the anterior mitral leaflet to the interventricular septum were detected in the majority of the patients. Anomalous, hypertrophied, and fused PM with muscularis trabeculae hypertrophy were a common findings. Four patients had posterior leaflet redundancy. Secondary chordae (90%), PM and muscularis trabeculae resection and PM splitting and elongation (77%) were added variably to septal myectomy (100%). Nine procedures (6%) on mitral valve leaflets were performed, involving 6 posterior and 3 anterior mitral leaflets. Long–term follow up was 4.6±3.7 years. There was no hospital mortality, and NYHA was reduced from 3±0.6 to 1±0.7 (p &lt; 0.0001), the LVOT gradient from 91±35 to 21±17 mmHg (p &lt; 0.0001), mitral valve regurgitation from grade 3±1 to 1±0.6 (p &lt; 0.0001), and septum thickness from 19±3 to 14±2 mm (p &lt; 0.0001).

Conclusions

The mitral valve apparatus with all its components contribute variably to LVOT dynamic obstruction thus, surgical correction in addition to extended myectomy is recommended to achieve the best outcome.

Exploring Kid Space in the wild: a preliminary study of multimodal and immersive collaborative play-based learning experiences

Parents recognize the potential benefits of technology for their young children but are wary of too much screen time and its potential deficits in terms of social engagement and physical activity. To address these concerns, related literature suggests technology usages with a blend of digital and physical learning experiences. Towards this end, we developed Kid Space, incorporating immersive computing experiences designed to engage children more actively in physical movement and social collaboration during play-based learning. The technology features an animated peer learner, Oscar, who aims to understand and respond to children's actions and utterances using extensive multimodal sensing and sensemaking technologies. To investigate student engagement during Kid Space learning experiences, an exploratory case study was designed using a formative research method with eight first-grade students. Multimodal data (audio and video) along with observational, interview, and questionnaire data were collected and analyzed. The results show that the students demonstrated high levels of engagement, less attention focused on the screen (projected wall), and more physical activity. In addition to these promising results, the study also enabled us to understand actionable insights to improve Kid Space for future deployments (e.g., the need for real-time personalization). We plan to incorporate the lessons learned from this preliminary study and deploy Kid Space with real-time personalization features for longer periods with more students.

2020 EACTS/ELSO/STS/AATS Expert Consensus on Post-cardiotomy Extracorporeal Life Support in Adult Patients

Post-cardiotomy extracorporeal life support (PC-ECLS) in adult patients has been used only rarely but recent data have shown a remarkable increase in its use, almost certainly due to improved technology, ease of management, growing familiarity with its capability and decreased costs. Trends in worldwide in-hospital survival, however, rather than improving, have shown a decline in some experiences, likely due to increased use in more complex, critically ill patients rather than to suboptimal management. Nevertheless, PC-ECLS is proving to be a valuable resource for temporary cardiocirculatory and respiratory support in patients who would otherwise most likely die. Because a comprehensive review of PC-ECLS might be of use for the practitioner, and possibly improve patient management in this setting, the authors have attempted to create a concise, comprehensive and relevant analysis of all aspects related to PC-ECLS, with a particular emphasis on indications, technique, management and avoidance of complications, appraisal of new approaches and ethics, education and training.

2020 EACTS/ELSO/STS/AATS expert consensus on post-cardiotomy extracorporeal life support in adult patients

Post-cardiotomy extracorporeal life support (PC-ECLS) in adult patients has been used only rarely but recent data have shown a remarkable increase in its use, almost certainly due to improved technology, ease of management, growing familiarity with its capability and decreased costs. Trends in worldwide in-hospital survival, however, rather than improving, have shown a decline in some experiences, likely due to increased use in more complex, critically ill patients rather than to suboptimal management. Nevertheless, PC-ECLS is proving to be a valuable resource for temporary cardiocirculatory and respiratory support in patients who would otherwise most likely die. Because a comprehensive review of PC-ECLS might be of use for the practitioner, and possibly improve patient management in this setting, the authors have attempted to create a concise, comprehensive and relevant analysis of all aspects related to PC-ECLS, with a particular emphasis on indications, technique, management, and avoidance of complications, appraisal of new approaches and ethics, education, and training.

2020 EACTS/ELSO/STS/AATS expert consensus on post-cardiotomy extracorporeal life support in adult patients

Post-cardiotomy extracorporeal life support (PC-ECLS) in adult patients has been used only rarely but recent data have shown a remarkable increase in its use, almost certainly due to improved technology, ease of management, growing familiarity with its capability and decreased costs. Trends in worldwide in-hospital survival, however, rather than improving, have shown a decline in some experiences, likely due to increased use in more complex, critically ill patients rather than to suboptimal management. Nevertheless, PC-ECLS is proving to be a valuable resource for temporary cardiocirculatory and respiratory support in patients who would otherwise most likely die. Because a comprehensive review of PC-ECLS might be of use for the practitioner, and possibly improve patient management in this setting, the authors have attempted to create a concise, comprehensive and relevant analysis of all aspects related to PC-ECLS, with a particular emphasis on indications, technique, management and avoidance of complications, appraisal of new approaches and ethics, education and training.

2020 EACTS/ELSO/STS/AATS Expert Consensus on Post-Cardiotomy Extracorporeal Life Support in Adult Patients

Post-cardiotomy extracorporeal life support (PC-ECLS) in adult patients has been used only rarely but recent data have shown a remarkable increase in its use, almost certainly due to improved technology, ease of management, growing familiarity with its capability and decreased costs. Trends in worldwide in-hospital survival, however, rather than improving, have shown a decline in some experiences, likely due to increased use in more complex, critically ill patients rather than to suboptimal management. Nevertheless, PC-ECLS is proving to be a valuable resource for temporary cardiocirculatory and respiratory support in patients who would otherwise most likely die. Because a comprehensive review of PC-ECLS might be of use for the practitioner, and possibly improve patient management in this setting, the authors have attempted to create a concise, comprehensive and relevant analysis of all aspects related to PC-ECLS, with a particular emphasis on indications, technique, management and avoidance of complications, appraisal of new approaches and ethics, education and training.

Echocardiography to estimate high filling pressure in patients with heart failure and reduced ejection fraction

Aims

Echocardiographic assessment of left ventricular filling pressures is performed using a multi‐parametric algorithm. Unselected sample of patients with heart failure with reduced ejection fraction (HFrEF) patients may demonstrate an indeterminate status of diastolic indices making interpretation challenging. We sought to test improvement in the diagnostic accuracy of standard and strain echocardiography of the left ventricle and left atrium (LA) to estimate a pulmonary capillary wedge pressure (PCWP) > 15 mmHg in patients with HFrEF.

Methods and results

Out of 82 consecutive patients, 78 patients were included in the final analysis and right heat catheterization, and echocardiogram was performed simultaneously. According to the univariable analysis, E wave velocity, the ratio between E‐wave/A‐wave (E/A, area under the curve [AUC] = 0.81, respectively), isovolumic relaxation time (AUC = 0.83), pulmonary vein D wave (AUC = 0.84), pulmonary vein S/D Ratio (AUC = 0.85), early pulmonary regurgitation velocity (AUC = 0.80), and accelerationa time at right ventricular out‐flow tract (RVOT AT, AUC = 0.84) identified with the highest accuracy PCWP > 15 mmHg. They were all tested in multivariate analysis, and they were not independently correlated with PCWP. Tricuspid regurgitation (TR) velocity was measurement with the highest predictive value in identifying PCWP > 15 mmHg (AUC = 0.89), compared with other established parameters such as the ratio between e‐wave velocity divided by mitral annular e' velocity (E/e'), deceleration time, or LA indexed volume (LAVi), which all reached a lower accuracy level (AUC = 0.75; 0.78; 0.76). Among strain measures, global longitudinal strain in four chamber view (GLS 4ch), the ratio between e‐wave velocity divided by mitral annular e' strain rate (E/e'sr), and LA longitudinal strain at the reservoir phase were helpful in estimating elevated PCWP (AUC = 0.77; 0.76; 0.75). According to multivariable analysis, the following two models had the greatest accuracy in detecting PCWP > 15 mmHg: (i) TR velocity, LAVi, and E wave velocity (receiver operating characteristic [ROC]‐AUC = 0.98), (ii) AT RVOT, LAVi and GLS 4ch (ROC‐AUC = 0.96). Neither E/A (ROC‐AUC = 0.81) nor E/e' (ROC‐AUC = 0.75) was an independent predictor when included in the model. The two MODELS were applicable to the entire population and demonstrated better agreement with the invasive reference (91% and 88%) than the guidelines algorithm (77%) regardless of the type of rhythm.

Conclusions

Our suggested echocardiographic approach could be used to potentially reduce the frequency of “doubtful” classification and increase the accuracy in predicting elevated left ventricular filling pressure leading to a decrease in the number of invasive assessment made by right heart catheterization.

Baseline surgical status and short-term mortality after extracorporeal membrane oxygenation for post-cardiotomy shock: a meta-analysis

OBJECTIVE

While reported mortality rates on post-cardiotomy extracorporeal membrane oxygenation vary from center to center, impact of baseline surgical status (elective/urgent/emergency/salvage) on mortality is still unknown.

METHODS

A systematic search was performed according to Preferred Reporting Items for Systematic Reviews and Meta-Analyses statement using PubMed/Medline databases until March 2018 using the keywords "postcardiotomy," "cardiogenic shock," "extracorporeal membrane oxygenation," and "extracorporeal life support." Relevant articles were scrutinized and included in the meta-analysis only if reporting in-hospital/30-day mortality and baseline surgical status. The correlations between mortality and percentage of elective/urgent/emergency cases were investigated. Inference analysis of baseline status and extracorporeal membrane oxygenation complications was conducted as well.

RESULTS

Twenty-two studies (conducted between 1993 and 2017) enrolling N = 2,235 post-cardiotomy extracorporeal membrane oxygenation patients were found. Patients were mostly of non-emergency status (65.2%). Overall in-hospital/30-day mortality event rate (95% confidence intervals) was 66.7% (63.3-69.9%). There were no differences in in-hospital/30-day mortality with respect to baseline surgical status in the subgroup analysis (test for subgroup differences; p = 0.406). Similarly, no differences between mortality in studies enrolling <50 versus ⩾50% of emergency/salvage cases was found: respective event rates were 66.9% (63.1-70.4%) versus 64.4% (57.3-70.8%); p = 0.525. Yet, there was a significant positive association between increasing percentage of emergency/salvage cases and rates of neurological complications (p < 0.001), limb complications (p < 0.001), and bleeding (p = 0.051). Incidence of brain death (p = 0.099) and sepsis (p = 0.134) was increased as well.

CONCLUSION

Other factors than baseline surgical status may, to a higher degree, influence the mortality in patients treated with extracorporeal membrane oxygenation for post-cardiotomy cardiogenic shock. Baseline status, however, strongly influences the complication occurrence while on extracorporeal membrane oxygenation.

Computational modeling of bicuspid aortopathy: Towards personalized risk strategies

This paper describes current advances on the application of in-silico for the understanding of bicuspid aortopathy and future perspectives of this technology on routine clinical care. This includes the impact that artificial intelligence can provide to develop computer-based clinical decision support system and that wearable sensors can offer to remotely monitor high-risk bicuspid aortic valve (BAV) patients. First, we discussed the benefit of computational modeling by providing tangible examples of in-silico software products based on computational fluid-dynamic (CFD) and finite-element method (FEM) that are currently transforming the way we diagnose and treat cardiovascular diseases. Then, we presented recent findings on computational hemodynamic and structural mechanics of BAV to highlight the potentiality of patient-specific metrics (not-based on aortic size) to support the clinical-decision making process of BAV-associated aneurysms. Examples of BAV-related personalized healthcare solutions are illustrated.

Impact of cannula design on packed red blood cell transfusions: technical advancement to improve outcomes in extracorporeal membrane oxygenation

Background

Technological improvement has contributed to making veno-venous extracorporeal membrane oxygenation (VV-ECMO) safer and easier, spreading its use in acute respiratory failure (ARF).

Methods

This is a retrospective observational study carried out in the ECMO center at IRCCS-ISMETT, a medical center focused on end-stage organ failure treatment in Italy. We investigated the effect of different cannula designs on the amount of blood product transfused. Eighty-nine consecutive patients affected with ARF on VV-ECMO from 2008 to 2016 were compared according to type of cannulation: older percutaneous cannula (Standard group, 52 patients) and HLS^© BIOLINE-coated, but with shorter drainage cannula (BIOLINE group, 37 patients).

Results

The two study groups were comparable in terms of baseline characteristics [age, body mass index (BMI), Simplified Acute Physiology Score (SAPS-II), Sequential Organ Failure Assessment (SOFA), Predicting Death For Severe ARDS on VV-ECMO (PRESERVE) score] and ECMO management [median hematocrit (Htc), platelet nadir, antithrombin III (AT III), heparin, activated partial thromboplastin time (APTT)]. In the BIOLINE group, a lower amount of packed red blood cells (pRBC) was transfused considering both total number [4 units, interquartile range (IQR) 1-9 vs. 12 units, IQR 5.5-21; P<0.01] and mL of pRBC/day of ECMO support (91, IQR 21-158 vs. 193.5, IQR 140.5-254; P<0.01). In the BIOLINE group, a trend in reduction of ECMO days (P=0.05) and length of intensive care unit (ICU) stay was found (P=0.06), but no differences in rates of ECMO weaning and ICU discharge were evidenced. The BIOLINE group constituted a saving of €1,295.20 per patient/treatment, counting the costs for cannulation and pRBC administration.

Conclusions

More biocompatible and shorter drainage cannula may represent one of the contributing factors to a reduction in transfusions and costs of VV-ECMO in the current ongoing technological improvement in ECMO.

Modalities and Effects of Left Ventricle Unloading on Extracorporeal Life support: a Review of the Current Literature

INTRODUCTION/AIM

Veno-arterial extracorporeal membrane oxygenation (V-A ECMO) support is increasingly used in refractory cardiogenic shock and cardiac arrest, but is characterized by a rise in afterload of the left ventricle (LV) which may ultimately either further impair or delay cardiac contractility improvement. The aim of this study was to provide a comprehensive overview regarding the different LV venting techniques and results currently available in the literature.

METHODS

A systematic literature search was performed in the PubMed database: 207 articles published between 1993 and 2016 were included. Papers dealing with pre-clinical studies, overlapping series, and association with other assist devices were excluded from the review, with 45 published papers finally selected. Heterogeneous indications for LV unloading were reported. The selected literature was divided into subgroups, according to the location or the performed procedure for LV venting.

RESULTS

Case reports or case series accounted for 60% of the papers, while retrospective study represented 29% of them. Adult series were present in 67%, paediatric patients in 29%, and a mixed population in 4%. LV unloading was performed percutaneously in 84% of the cases. The most common locations of unloading was the left atrium (31%), followed by indirect unloading (intra-aortic balloon pump) (27%), trans-aortic (27%), LV (11%), and pulmonary artery (4%). Percutaneous trans-septal approach was reported in 22%. Finally, the unloading was conducted surgically in 16%,with open chest surgery in 71%, and minimally invasive surgery in 29% of surgical cases.

CONCLUSION

Nowadays, only a few data are available about left heart unloading in V-A ECMO support. Despite the well-known controversy, IABP remains widely used in combination with V-A ECMO. Percutaneous approaches utilizing unloading devices is becoming an increasingly used option. However, further studies are required to establish the optimal LV unloading method.

Robotic mitral repair with sliding leaflet valvuloplasty and remodelling partial annuloplasty

Complex pathoanatomy that requires posterior leaflet height reduction can be accomplished robotically with excellent surgical outcomes. We report the technique of robotic sliding leaflet valvuloplasty in cases of severe myxomatous degenerative disease with elevated predictive risk of systolic anterior motion.

ISMETT: An International Collaboration on Organ Transplantation

The Institute of the Mediterranean for Transplantation and High Specialty Therapies (ISMETT) is a multi-organ transplant and high specialty center located in Palermo, Italy and managed by the University of Pittsburgh Medical Center. Clinical transplant activity started in 1999 and, herein, we illustrate the outcomes achieved over the past 15 years. In total, ISMETT has performed 997 liver transplants (83.9% adults, 16.1% pediatrics) with a significant percentage of liver transplants from cadaver split livers (17%) and partial grafts from living donors (11.5%). Among liver transplant recipients, the overall five-year graft survival was 74.3% in the adult population and 79% in the pediatric population. ISMETT has also performed 419 kidney transplants in total: 211 from cadaveric donors (22 double), 176 from living donors, and 32 combined (19 with liver, 11 with pancreas, and 2 with heart). The 5-year renal graft survival was 82.2% (cadaveric donor) and 92.2% (living donor). More recently, in 2005, ISMETT started pancreas, lung, and heart transplant programs. In total, 16 pancreas transplants have been performed, of which 12 were simultaneous pancreas-kidney transplants, 1 was pancreas after kidney, and 3 were pancreas alone transplants. One pancreatic islet transplant was also performed in a patient who had already undergone kidney transplantation. Patient and pancreas graft survivals at 1 year were 86.7% and 73.3%, respectively, and 80% and 73.3% at five years (pancreas survival is defined as normoglycemia and insulin-independence). Lung transplant has been performed in 133 patients (116 double and 17 single lung). Eleven were pediatric (8% of all transplants). The 1-month, 1-year, and 5-year overall graft survivals were, 93.8%, 81.4%, and 75.6%, respectively. Heart transplantation has been performed in 133 adults (85% were male). Coronary artery disease and cardiomyopathy were the leading underlying heart disease diagnoses leading to transplant. Mechanical support (ventricular assist device or extracorporeal membrane oxygenation) as a bridge to transplant was used in 18% of the heart transplant cases. One-year heart graft survival was 83% and 5-year heart graft survival was 81%.

Novel achromatic single reflection quarter-wave retarder: design and measurement

In this work, we present an achromatic quarter-wave retarder whose design is based upon the reflection properties of an isotropic-anisotropic interface. In theory, it is possible to obtain a π/2 phase shift by means of a total internal reflection at an isotropic-isotropic interface. However, in order to achieve such a phase shift, it is necessary to use a medium with a particularly high refractive index. We have previously shown that these phase shifts can be achieved by means of a total internal reflection in an isotropic-uniaxial interface, which allows the use of smaller refractive index media. By means of this property, we designed, built, and characterized a novel quarter-wave retarder that makes it possible to obtain circularly polarized light from a linear polarization state. We developed some guidelines that allowed us to obtain a device of competitive performance, low cost, and manageable manufacture.

6 months of "temporary" support by Levitronix left ventricular assist device

An otherwise healthy 47-year-old man presented to the emergency department in cardiogenic shock after suffering a massive myocardial infarction due to left main occlusion. He was initially supported by extracorporeal membrane oxygenation and subsequently was converted to paracorporeal support with a Levitronix left ventricular assist device. He experienced multiple postoperative complications including renal failure, respiratory failure, retroperitoneal hematoma requiring suspension of anticoagulation, and fungal bloodstream infection precluding transition to an implantable device. He was reconditioned and successfully underwent orthotopic heart transplant 183 days after presentation. A discussion of the relevant issues is included.

Potential clinical role of telomere length in human glioblastoma

Glioblastoma Multiforme (GBM) is the most common and lethal of human primary central nervous system (CNS) tumors. Due to the tumour's intrinsic clinical and molecular heterogeneity, choice of initial treatment, prediction of survival, stratification of patients, prediction and monitoring of response to therapy, represent some of the greatest challenges in the management of GBM patients. Patients, despite optimal surgery, radiation and chemotherapy, still have a median survival of 14-16 months. A reason for this dismal prognosis is because of the relative inaccuracy of current prognostic markers, so far based on clinical or pathological variables. Molecular markers that effectively predict response to therapy and survival outcomes are limited. Consequently, there is a strong need to develop novel and independent markers of prognosis. Ideal biomarkers for solid tumors would serve one or more important functions. Telomeres, guanine-rich tandem DNA repeats of the chromosomal end, provide chromosomal stability, regulates important cellular processes, and seem to be implicated in human carcinogenesis. Recently, telomeres have been shown either to be associated with clinical markers of disease progression or to be independent markers of cancer prognosis in solid tumours, including GBM. Nevertheless, a corresponding comprehensive discussion of these promising developments in brain tumours has not yet been available in the literature. Therefore, here we reviewed studies focused on the assessment of telomeric length in brain tumours with the aim to emphasized those findings indicating a potential clinical role of telomeres in GBM. With the aim to enhance the awareness of the potential clinical role of telomeres' length information in GBM, using a southern blot analysis, telomeric length in excised tumour samples was analyzed. Moreover, an attempt to correlated telomere length with patients' overall survival, was also performed. The findings here reviewed shows some contradictory results, due to different tissues used as controls, but mainly to cellular and molecular heterogeneity in GBMs that drive molecular mechanisms controlling telomere length, included telomerase and Alternative Lengthening of Telomeres (ALT), through multiple mechanisms. However, overall these studies, including our own, are consistent with the hypothesis that GBMs' telomeres were always shorter when compared with Normal Brain Tissue (NBT), and together with higher telomerase activity seem to be associated with malignancy and poor outcome; while tumours with ALT phenotype have longer telomeres, "less malignant" behaviour and better prognosis. We conclude that, although not entirely consistent in the type of telomere alteration, i.e., attrition vs. elongation, and unclear on the underlying mechanisms, multiple studies in brain tumours have shown that telomere dysfunctions are associated with parameters of clinical outcome in patients with GBMs and therefore will be part of novel risk assessment and prognostic modalities for patients with these still dismal disease.

Incidence of neoplastic disease following lung transplantation: a 17-year single-center experience

OBJECTIVE

Chronic immunosuppressive therapy following solid organ transplantation has been correlated with an increased risk of posttransplantation neoplastic disease (PTND). In this study we evaluated PTND incidence and outcome at our institution over a 17-year period among patients receiving lung transplantation.

MATERIALS AND METHODS

Between February 1992 and December 2008, we performed 290 lung transplantations in 280 patients, including 139 single (48% with 5 retransplantations), and 151 double lung transplantations (52% with 5 retransplantations). Among the 280 patients, 2 had undergone previous double lung transplantation in other hospitals. Follow-up of transplant recipients was performed up to December 2009.

RESULTS

Forty-two patients died in the hospital, producing a cumulative early (30-day) mortality rate of 15%. Among the 238 patients discharged from the hospital who entered our follow-up program, 36 (15%) experienced PTND. The mean time between transplantation and diagnosis was 47 ± 42 months, and patients' mean age at time of diagnosis was 55 ± 14 years. Overall freedom from PTND was 97%, 84%, and 73% at 1, 5, and 10 years, respectively. PTND was considered to be the direct cause of death in 11 patients (30%). Overall survival of patients with PTND at five years (45%) did not differ from the remainder of the transplanted population (46%). However, PTND became a relevant cause of death in the long-term (>5 years) follow-up.

CONCLUSION

Our experience confirms that PTND was frequently diagnosed following lung transplantation. Even if PTND did not seem to significantly affect the survival of patients undergoing lung transplantation, it may become a significant cause of death among those surviving beyond 5 years.

Aortic valve replacement by ministernotomy in redo patients with previous left internal mammary artery patent grafts

OBJECTIVE

Aortic valve surgery with a patent left internal mammary artery (LIMA) on the left anterior descending (LAD) coronary artery is challenging in terms of myocardial protection and graft injury. Minimally invasive techniques may require minimal dissection of adhesions and may eventually decrease the risk of injuries.

METHODS

Since 1997, more than 1000 ministernotomies have been performed by our surgical unit. Of these, 16 patients (14 males, 2 females, mean age: 68.7 years) had a patent LIMA graft on LAD. Fourteen underwent native aortic valve replacement, and in 2 a previously implanted prosthesis was replaced. A miniresternotomy was performed using either a "J" (15 patients) or a "reversed-T" method (1 patient).

RESULTS

Cardiopulmonary bypass (CPB) was achieved by either femoral vein (12 patients) or right atrium (4 patients); arterial inflow was achieved either by ascending aorta (12 patients) or by femoral artery (4 patients). Mean CPB time was 119.7 ± 38.1 minutes (range: 50-235). Mean cooling body temperature was 27.4 °C. Antegrade cold crystalloid cardioplegia was delivered to all the patients. Mean aortic cross-clamp time was 72 ± 20 minutes (range: 45-125). No damage to LIMA occurred in any of the patients. No intra- or perioperative myocardial infarction (MI) occurred. Neither a conversion to full sternotomy nor a reoperation for bleeding was needed. Mean postoperative bleeding was 426 ± 474 ml (range: 120-1950). A blood transfusion was necessary in 7 patients. Mean postoperative ICU stay was 1.6 ± 1.1 days. Mean postoperative hospital stay was 7.5 ± 2.6 days. Postoperative course was totally uneventful in 10 patients (58.8%). Follow-up was complete for a total of 928 patient/months (range: 11-124), and there were four late deaths, two of which were related to cardiac problems. Nine of the 12 survivors are in NYHA CLASS I . II. Prosthesis-related morbidity did not occur either early or late during follow-up.

CONCLUSIONS

This experience may represent the feasibility of an alternative surgical approach to a standard full-length median sternotomy in patients with previous coronary revascularization and with a patent LIMA on the LAD, requiring new surgery on the aortic valve.

Treatment of ascending aorta disease with Bentall-De Bono operation using a mini-invasive approach

BACKGROUND

Use of minimally invasive approaches in cardiac surgery is increasing, obtaining a wide consensus and representing a challenging alternative technique for many surgeons. We report our experience of the treatment of ascending aorta disease using the Bentall-De Bono procedure through a minimally invasive approach.

METHODS

Between September 1997 and June 2005 at 'Policlinico San Matteo', Pavia, we treated 40 patients affected by ascending aorta disease and aortic valve regurgitation using a Bentall-De Bono procedure through a minimally invasive approach, by means of a reversed T or J ministernotomy. Data were analyzed retrospectively. Thirty patients were men. Short-term and mid-term mortality and peroperative complications were analyzed.

RESULTS

None of the patients died during the 30-day postoperative period. The mean ICU and length of stay times were 3.3 +/- 8.2 and 9.3 +/- 7.2 days, respectively. Six patients (15%) had one or more postoperative complications. One patient (2.5%) underwent early reoperation for bleeding. None underwent a procedure-related reoperation. Mechanical ventilation was longer than 48 h in five patients (12.5%). The mean follow-up was 38.4 +/- 31 months. Survival at 1, 3 and 5 years was, respectively, 94.1, 90.6 and 90.6%. At the end of the follow-up, there were 37 survivors. Twenty-seven (73%) patients were in New York Heart Association I, six (16%) were in New York Heart Association II and four (11%) were in New York Heart Association III.

CONCLUSION

Reversed T or J ministernotomy is a feasible and secure alternative to complete sternotomy. The short incision may enhance the outcome and does not affect the survival, offering proper access to the anatomic structures.

TT virus has a ubiquitous diffusion in human body tissues: analyses of paired serum and tissue samples

The tissue tropism and possible correlation with liver disease of the TT virus (TTV) as well as its prevalence and genotype distribution remain undefined. TTV-DNA was investigated in paired sera and tissue samples from 144 patients, and sera and cerebrospinal fluids (CSF) from additional six subjects. Of the 144 tissue samples, 128 were liver biopsy specimens from subjects with hepatic disease while 16 were surgically obtained nonliver specimens from patients with extrahepatic disease. TTV cloning, sequencing and genotype analyses were performed on isolates from sera, tissue specimens and peripheral blood mononuclear cells of two patients with hepatic and four patients with extrahepatic pathologies, as well as from sera and CSFs of two subjects. TTV was found in 100% of the examined tissues and in 60.1 and 50% of sera from patients with hepatic and extrahepatic pathologies, respectively. Moreover, TTV was detected in four of the six CSFs analysed but only in two correspondent sera. Genotyping revealed the coexistence of multiple TTV genotypes and genetic variants in each infected individual, and the analysis of TTV mRNA showed the presence of transcripts in all the six different tissues studied. These results indicate that the entire adult population in our area is more likely infected by TTV, although several subjects are not viraemic and that TTV infects many different human tissues and is able to invade the central nervous system.

Is investigation of hepatitis C virus NS5A gene heterogeneity a tool for predicting long-lasting response to interferon therapy in patients with HCV-1b chronic hepatitis?

Nonstructural protein 5A (NS5A) of the hepatitis C virus (HCV) may repress the interferon (IFN)-induced protein kinase R (PKR). High variability of different regions in the carboxy-terminal half of NS5A implicated in the interaction with PKR (particularly the interferon sensitivity determining region (ISDR)) may be a predictor of response to IFN in patients infected with genotype 1b of HCV. We examined pretreatment serum samples from 17 HCV-1b infected patients included in the same schedule of IFN therapy. Seven patients were a rare series of sustained responders (SR) with a post-treatment follow-up of 5-7 years, while ten were nonresponders (NR). The carboxy-terminal half of the NS5A gene was amplified and directly sequenced in all 17 cases. In addition, the entire NS5A gene and the part of the HCV E2 gene coding for the hypervariable region 1 (HVR1) were amplified, cloned and sequenced in six cases (three NR and three SR). No difference in number and distribution of amino acid mutations was observed between isolates from SR and NR in any portion of the protein, including the ISDR region. Analysis of full length NS5A confirmed no difference between the two groups. The NS5A gene sequence was different among the six cases cloned although it appeared to be conserved in each individual patient independently of the quasispecies complexity evaluated through HVR1 examination. These data indicate that pretreatment analysis of theNS5A genomic variability has no value in predicting long-lasting response to IFN therapy in HCV-1b-infected patients, and that the HCV NS5A gene has high quasispecies homology.

Analysis of haemochromatosis gene mutations in a population from the Mediterranean Basin

BACKGROUND/AIMS

The C282Y mutation in the haemochromatosis gene (HFE) located on chromosome 6 has been identified as the main genetic basis of hereditary haemochromatosis (HH). Two more mutations of that gene, H63D and S65C, appear to be associated with milder forms of HH. A high allele frequency for C282Y and H63D mutations was reported in populations from North Europe, while incomplete information is available for individuals from the Mediterranean Basin where C282Y homozygotes comprise a smaller percentage of HH cases. In this study we investigated the allele frequency of HFE mutations and the association between HFE mutations and cases of HH in a population from the South of Italy (Sicily and Calabria). In addition, we evaluated a possible association between HFE mutations and either chronic liver disease or type II diabetes.

PATIENTS AND METHODS

Three hundred and twenty-seven individuals (654 chromosomes) were tested for C282Y, H63D and S65C mutations of the HFE gene by restriction fragment length polymorphism. Four had HH, 23 had hepatocellular carcinoma, 100 had chronic liver disease, 100 had type II diabetes, and 100 were healthy controls.

RESULTS

Both C282Y and S65C mutations were each detected in one of the 654 chromosomes analysed (allele frequency=0.15%), while H63D change was found in 122 chromosomes (allele frequency=18.6%) and was equally distributed in all the categories examined. One healthy individual had compound heterozygosity for C282Y and H63D mutations. The frequency of C282Y in this Southern Italian sample was the lowest yet reported for a population of European origin. None of the four HH patients was either homozygous or heterozygous for C282Y.

CONCLUSIONS

In Mediterranean populations from Southern Italy the C282Y mutation occurs sporadically and HFE polymorphisms seem to have little diagnostic relevance.