Sex differences in readmission rate after cardiac surgery

Introduction

The impact of sex on hospital readmission rate after cardiac surgery is unclear. Therefore, we aimed to analyse sex-specific differences and underlying factors in 30-day readmission rate after cardiac surgery.

Methods

We conducted a single center study including all patients after major cardiac surgery (excluding aortic dissection and left ventricular assist device implantation) from January 2012 to September 2020. Reasons for readmission were adjudicated according to all available medical records. We calculated incidence rate ratios (IRR) with 95% confidence intervals (CI) for female sex with re-admission crude and adjusted for plausible confounding factors using negative binomial regression.

Results

4,868 patients were included in the analysis. The median [Interquartile range] age was 68 [60 to 74] years and 24% (n = 1,149) of the patients were female. Female patients were significantly older (median [IQR] age 70 (63 to 76) vs. 67 (59 to 74), p < 0.001) and had lower body mass index and fewer cardiovascular risk factors compared to men. Isolated valve surgery was more frequent in female while coronary artery bypass grafting was more often in men. 30-day readmission was comparable between both sexes (7.0% [n = 81] in female vs. 8.7% [n = 322] in men; p = 0.078). Cardiac related readmissions and infections were the most common reasons for readmission in both groups. The overall incidence rate ratios of female sex with readmission (0.80, 95% CI 0.63 to 1.03, p = 0.078) remained robust after adjustment for EuroSCORE 2 (0.78, CI 0.61 to 1.0, p = 0.051).

Conclusion

Readmission rate and reasons for 30-day readmission after major cardiac surgery were similar between men and women.

Composite haemangioendothelioma in the heart: a case report

BACKGROUND

Primary cardiac neoplasm is rare and generally benign. Epithelioid haemangioendothelioma, a potentially malignant tumour of vascular origin, has been occasionally described in the heart. Composite haemangioendothelioma, characterized by a heterogeneous architecture of vascular components and usually located in soft tissue of the extremities, has only been reported twice in the heart. We herein report another case of this extremely uncommon cardiac tumour.

CASE SUMMARY

Comprehensive cardiac examination of a 59-year-old female patient with palpitations and personal history of Hodgkin's lymphoma and chest radiation revealed a mass in the left atrium. After surgical resection, histopathological and immunohistochemical analysis identified a composite haemangioendothelioma. After two years, repeated imaging revealed neither signs of local relapse nor metastasis.

CONCLUSIONS

Composite haemangioendothelioma, a very uncommon form of potentially malignant vascular tumour, can also be encountered in the heart. In this present case, the outcome was favourable two years after surgical resection without adjuvant therapy.

Hyperacute T Wave in the Early Diagnosis of Acute Myocardial Infarction

STUDY OBJECTIVE

The diagnostic performance of T-wave amplitudes for the detection of myocardial infarction is largely unknown. We aimed to address this knowledge gap.

METHODS

T-wave amplitudes were automatically measured in 12-lead ECGs of patients presenting with acute chest discomfort to the emergency department within a prospective diagnostic multicenter study. The final diagnosis was centrally adjudicated by 2 independent cardiologists. Patients with left ventricular hypertrophy, complete left bundle branch block, or paced ventricular depolarization were excluded. The performance for lead-specific 95th-percentile thresholds were reported as likelihood ratios (lr), specificity, and sensitivity.

RESULTS

Myocardial infarction was the final diagnosis in 445 (18%) of 2457 patients. In most leads, T-wave amplitudes tended to be greater in patients without myocardial infarction than those with myocardial infarction, and T-wave amplitude exceeding the 95th percentile had positive and negative lr close to 1 or with confidence intervals (CIs) crossing 1. The exceptions were leads III, aVR, and V1, which had positive lrs of 3.8 (95% CI, 2.7 to 5.3), 4.3 (95% CI, 3.1 to 6.0) and 2.0 (95% CI, 1.4 to 2.9), respectively. These leads normally have inverted T waves, so T-wave amplitude exceeding the 95th percentile reflects upright rather than increased-amplitude hyperacute T waves.

CONCLUSION

Hyperacute T waves, when defined as increased T-wave amplitude exceeding the 95th percentile, did not provide useful information in diagnosing myocardial infarction in this sample.

Combined Band and Plate Fixation as a New Individual Option for Patients at Risk of Sternal Complications after Cardiac Surgery: A Single-Center Experience

Due to the advent of interventional therapies for low- and intermediate-risk patients, case complexity has increased in cardiac surgery over the last decades. Despite the surgical progress achieved to keep up with the increase in the number of high-risk patients, the prevention of sternal complications remains a challenge requiring new, individualized sternal closure techniques. The aim of this study was to evaluate the safety and feasibility, as well as the in-hospital and long-term outcomes, of enhanced sternal closure with combined band and plate fixation using the new SternaLock^® 360 (SL360) system as an alternative to sternal wiring. From 2020 to 2022, 17 patients underwent enhanced sternal closure using the SL360 at our institution. We analyzed perioperative data, as well as clinical and radiologic follow-up data. The results were as follows: In total, 82% of the patients were treated with the SL360 based on perioperative risk factors, while in 18% of cases, the SL360 was used for secondary closure due to sternal instability. No perioperative complications were observed. We obtained the follow-up data of 82% of the patients (median follow-up time: 141 (47.8 to 511.5) days), showing no surgical revision, no sternal instability, no deep wound infections, and no sternal pain at the follow-up. In one case, a superficial wound infection was treated with antibiotics. In conclusion, enhanced sternal closure with the SL360 is easy to perform, effective, and safe. This system might be considered for both primary and secondary sternal closure in patients at risk of sternal complications.

Detrimental consequences after intimal disruption of subclavian artery during transcathether aortic valve implantation

BACKGROUND

TAVI via the left subclavian artery is considered a bail-out strategy in cases where a transfemoral approach is not feasible. However, since this route is only scarcely used, major complications can arise. We describe such an adverse course and present our proceeding.

CASE PRESENTATION

A 65-year-old man with severe aortic valve stenosis (AS) was referred for transcatheter aortic valve implantation (TAVI) via left subclavian artery. After uneventful deployment of the TAVI prosthesis, consequent valve assessment with transeosophageal echocardiography and angiography showed a highly mobile and tubular structure shifting within the valve. We went for a surgical extraction via sternotomy on cardiopulmonary bypass (CPB). A 6 cm longish intimal cylinder was hassle-free extracted. 4 days postoperatively the left sided radial pulse was missing. In a subsequent computed tomography angiography (CTA) scan a proximal dissection as well as an intimal flap, causing a subtotal stenosis of the left subclavian artery, was detected. Consecutively the intimal cylinder was removed using a Fogarty-balloon. Pre-discharge control revealed recurrence of peripheral radial pulse and an unimpeded function of the TAVI prosthesis. The patient presented no sequela at discharge.

CONCLUSION

Though TAVI is a well-advanced technique complications are not completely avertable. It is thus advisable to have patients discussed in the heart team encompassing all potentially involved specialties.

Outcome of patients with double valve surgery between 2009 and 2018 at University Hospital Basel, Switzerland

Background

In isolated mitral valve regurgitation general consensus on surgery is to favor repair over replacement excluding rheumatic etiology or endocarditis. If concomitant aortic valve replacement is performed however, clinical evidence is more ambiguous and no explicit guidelines exist on the choice of mitral valve treatment. Both, double valve replacement (DVR) and aortic valve replacement in combination with concomitant mitral valve repair (AVR + MVP) have been proven to be feasible procedures. In our single-center, retrospective, observational cohort study, we compared the outcome of these two surgical techniques focusing on mortality and morbidity.

Methods

89 patients underwent DVR (n = 41) or AVR + MVP (n = 48) in our institution between 2009 and 2018. Follow-up data was collected using electronic patient records, by contacting treating physicians and by telephone interviews. We used the Kaplan–Meier method to analyze mortality during follow-up and Cox regression to investigate potential predictors of mortality.

Results

During a median follow-up duration of 4.5 [IQR 2.9 to 6.1] years, there was no significant difference in mortality between both cohorts. Thirty days mortality was 6.3% in the DVR and 7% in the AVR + MVP cohort. Overall mortality amounted to 17% for DVR and 23% for AVR + MVP. DVR was the preferred procedure for valve disease of rheumatic etiology and for endocarditis, while in degenerative valves AVR + MVP was predominant. More biological valves were used in the AVR + MVP cohort (p < 0.001) and more mechanical valves were implanted in the DVR cohort. The rate of rehospitalization, deterioration of left ventricular ejection fraction and postoperative complications were equally distributed among the two cohorts.

Conclusion

Our data analysis showed that both DVR and AVR + MVP are safe and feasible options for double valve surgery. Based on our findings we could not prove superiority of one surgical technique over the other. Choosing the appropriate procedure for the patient should be influenced by valve etiology, patients’ comorbidities and the surgeons’ experience.

Trial registration

This was a retrospectively registered trial, registered on April 1st 2018, ClinicalTrials.gov Identifier: NCT03667274.

Standardized Aortic Valve Neocuspidization for Treatment of Aortic Valve Diseases

BACKGROUND

Aortic valve replacement is the traditional surgical treatment for aortic valve diseases, yet standardized aortic valve neocuspidization (AVNeo) is a promising alternative that is gaining popularity. The purpose of this article is to review the available published literature of AVNeo using glutaraldehyde-treated autologous pericardium, also known as the Ozaki procedure, including indications, outcomes, potential benefits, and modes of failure for the reconstructed valve.

METHODS

A comprehensive literature search was performed using keywords related to aortic valve repair, AVNeo, or Ozaki procedure. All articles describing performance of AVNeo were reviewed.

RESULTS

Reported early mortality after AVNeo varies from 0% to 5.88%. The largest cohort of patients in the literature includes 850 patients with an inhospital mortality rate of 1.88%. Cumulative incidence of aortic valve reoperation was 4.2% in the largest series. Reoperation was uncommon and mainly due to infective endocarditis or degeneration of the reconstructed valve (most commonly due to aortic valve regurgitation, rather than stenosis).

CONCLUSIONS

Aortic valve neocuspidization is a versatile and standardized alternative to aortic valve replacement with a biological prosthesis. Early to midterm outcomes from a number of centers are excellent and demonstrate the safety and durability of the procedure. Long-term outcomes and clinical trial data are necessary to determine which patients benefit the most from this procedure.

Performance of the ESC 0/2h-algorithm using high-sensitivity cardiac troponin I in the early diagnosis of myocardial infarction

The 2020 guidelines of the European Society of Cardiology (ESC) recommend a novel ESC 0/2h-algorithm as the preferred alternative to the ESC 0/1h-algorithm in the early triage for rule-out and/or rule-in of Non-ST-segment-elevation myocardial infarction (NSTEMI). The aim was to prospectively validate the performance of the ESC 0/2h-algorithm using the high-sensitivity cardiac troponin I (hs-cTnI) assay (ARCHITECT) in an international, multicenter diagnostic study enrolling patients presenting with acute chest discomfort to the emergency department.

Long-Term Severe In Vitro Hypoxia Exposure Enhances the Vascularization Potential of Human Adipose Tissue-Derived Stromal Vascular Fraction Cell Engineered Tissues

The therapeutic potential of mesenchymal stromal/stem cells (MSC) for treating cardiac ischemia strongly depends on their paracrine-mediated effects and their engraftment capacity in a hostile environment such as the infarcted myocardium. Adipose tissue-derived stromal vascular fraction (SVF) cells are a mixed population composed mainly of MSC and vascular cells, well known for their high angiogenic potential. A previous study showed that the angiogenic potential of SVF cells was further increased following their in vitro organization in an engineered tissue (patch) after perfusion-based bioreactor culture. This study aimed to investigate the possible changes in the cellular SVF composition, in vivo angiogenic potential, as well as engraftment capability upon in vitro culture in harsh hypoxia conditions. This mimics the possible delayed vascularization of the patch upon implantation in a low perfused myocardium. To this purpose, human SVF cells were seeded on a collagen sponge, cultured for 5 days in a perfusion-based bioreactor under normoxia or hypoxia (21% and <1% of oxygen tension, respectively) and subcutaneously implanted in nude rats for 3 and 28 days. Compared to ambient condition culture, hypoxic tension did not alter the SVF composition in vitro, showing similar numbers of MSC as well as endothelial and mural cells. Nevertheless, in vitro hypoxic culture significantly increased the release of vascular endothelial growth factor (p < 0.001) and the number of proliferating cells (p < 0.00001). Moreover, compared to ambient oxygen culture, exposure to hypoxia significantly enhanced the vessel length density in the engineered tissues following 28 days of implantation. The number of human cells and human proliferating cells in hypoxia-cultured constructs was also significantly increased after 3 and 28 days in vivo, compared to normoxia. These findings show that a possible in vivo delay in oxygen supply might not impair the vascularization potential of SVF- patches, which qualifies them for evaluation in a myocardial ischemia model.

Impact on Mechanical Properties of 10 versus 20 Minute Treatment of Human Pericardium with Glutaraldehyde in OZAKI Procedure

Purpose: The aim of this study was to analyze the effects of 10-minute (standard term) versus 20-minute treatment with glutaraldehyde (GA) on mechanical stability and physical strength of human pericardium in the setting of the OZAKI procedure.

Methods: Leftover pericardium (6 patients) was bisected directly after the operation, and one-half was further fixed for 10 additional minutes. Uniaxial tensile tests were performed and ultimate tensile strength (UTS), ultimate tensile strain (uts), and collagen elastic modulus were evaluated.

Results: Both treatments resulted in similar values of uniaxial stretching-generated elongations at rupture (10 minutes 25 ± 7 % vs. 20 minutes: 22 ± 5 %; p = 0.05), UTS (5.16 ± 2 MPa vs. 6.54 ± 3 MPa; p = 0.59), and collagen fiber stiffness (elastic modulus: 31.80 ± 15.05 MPa vs. 37.35 ± 15.78 MPa; p = 0.25).

Conclusion: Prolongation of the fixation time of autologous pericardium has no significant effect on its mechanical stability; thus, extending the intraoperative treatment cannot be recommended.

Hemoadsorption during Cardiopulmonary Bypass in Patients with Endocarditis Undergoing Valve Surgery: A Retrospective Single-Center Study

Background: Aim of this study was to evaluate the outcomes of endocarditis patients undergoing valve surgery with the Cytosorb^® hemoadsorption (HA) device during cardiopulmonary bypass. Methods: From 2009 until 2019, 241 patients had undergone valve surgery due to endocarditis at the Department of Cardiac Surgery, University Hospital of Basel. We compared patients who received HA during surgery (n = 41) versus patients without HA (n = 200), after applying inverse probability of treatment weighting. Results: In-hospital mortality, major adverse cardiac and cerebrovascular events and postoperative renal failure were similar in both groups. Demand for norepinephrine (88.4 vs. 52.8%; p = 0.001), milrinone (42.2 vs. 17.2%; p = 0.046), red blood cell concentrates (65.2 vs. 30.6%; p = 0.003), and platelets (HA vs. Control: 36.7 vs. 9.8%; p = 0.013) were higher in the HA group. In addition, a higher incidence of reoperation for bleeding (34.0 vs. 7.7 %; p = 0.011), and a prolonged length of in-hospital stay (15.2 (11.8 to 19.6) vs. 9.0 (7.1 to 11.3) days; p = 0.017) were observed in the HA group. Conclusions: No benefits of HA-therapy were observed in patients with infective endocarditis undergoing valve surgery.

Clinical presentation of patients with prior coronary artery bypass grafting and suspected acute myocardial infarction

AIMS

Diagnosis of acute myocardial infarction (AMI) can be challenging in patients with prior coronary artery bypass grafting (CABG).

METHODS AND RESULTS

Final diagnoses were adjudicated by two independent cardiologists using the universal definition of AMI among patients presenting to the emergency department (ED) with suspected AMI. Diagnostic accuracy of 34 chest pain characteristics (CPCs) and four electrocardiogram (ECG) signatures stratified according to the presence or absence of prior CABG were prospectively quantified. Among 4015 patients (no prior CABG: n = 3686; prior CABG: n = 329), prevalence of AMI and unstable angina were higher in patients with prior CABG (35% vs. 18%; 26% vs. 8%; both P < 0.001). Three CPCs (9%) and two electrocardiographic findings (50%) showed a different diagnostic performance (interaction P < 0.05) with loss of diagnostic value in patients with prior CABG. The diagnostic accuracy as quantified by the area under the curve (AUC) of the integrated clinical judgement was moderate to good in patients with prior CABG, and significantly lower compared to patients without prior CABG [AUC 0.80 (95% confidence interval (CI) 0.75-0.84) vs. AUC 0.87 (95% CI 0.86-0.89); P = 0.004]. Time to discharge from the ED was significantly longer in patients with prior CABG [359 (215-525) min vs. 300 (192-435) min; P < 0.001]. Key findings were confirmed in a large independent external validation cohort (n = 13 653).

CONCLUSIONS

Patients with prior CABG presenting with suspected AMI have a high prevalence of AMI and unstable angina and lower diagnostic accuracy of CPCs and the ECG, possibly justifying liberal use of early coronary angiography in these vulnerable patients.

CLINICALTRIALS.GOV REGISTRY

Number NCT00470587.

Are three antiseptic paints needed for safe preparation of the surgical field? A prospective cohort study with 239 patients

Background

Preoperative skin antisepsis is an essential component of safe surgery. However, it is unclear how many antiseptic paints are needed to eliminate bacteria prior to incision. This study compared microbial skin counts after two and three antiseptic paints.

Methods

We conducted a prospective cohort study in non-emergency patients receiving a cardiac/abdominal surgery with standardized, preoperative skin antisepsis consisting of an alcoholic compound and either povidone iodine (PI) or chlorhexidine (CHX). We obtained three skin swabs from the participant’s thorax/abdomen using a sterile template with a 25 cm² window: After collection of the first swab prior to skin antisepsis, and once the second and third application of PI/CHX had dried out, we obtained a second and third swab, respectively. Our primary outcome was the reduction in microbial skin counts after two and three paints of PI/CHX.

Results

Among the 239 enrolled patients, there was no significant difference in the reduction of mean square root-transformed microbial skin counts with three versus two paints (P = 0.2). But distributions of colony forming units (CFUs) decreased from paint 2 to 3 in a predefined analysis (P = 0.002). There was strong evidence of an increased proportion of patients with zero CFU after paint 3 versus paint 2 (P = 0.003). We did not identify risk factors for insufficient reduction of microbial skin counts after two paints, defined as the detection of > 5 CFUs and/or ≥ 1 pathogens.

Conclusions

In non-emergency surgical patients, three antiseptic paints may be superior to two paints in reducing microbial skin colonization prior to surgery.

Frequent Door Openings During Cardiac Surgery Are Associated With Increased Risk for Surgical Site Infection: A Prospective Observational Study

BACKGROUND

Preliminary studies that analyzed surrogate markers have suggested that operating room (OR) door openings may be a risk factor for surgical site infection (SSI). We therefore aimed to estimate the effect of OR door openings on SSI risk in patients undergoing cardiac surgery.

METHODS

This prospective, observational study involved consecutive patients undergoing cardiac surgery in 2 prespecified ORs equipped with automatic door-counting devices from June 2016 to October 2017. Occurrence of an SSI within 30 days after cardiac surgery was our primary outcome measure. Respective outcome data were obtained from a national SSI surveillance cohort. We analyzed the relationship between mean OR door opening frequencies and SSI risk by use of uni- and multivariable Cox regression models.

RESULTS

A total of 301 594 OR door openings were recorded during the study period, with 87 676 eligible door openings being logged between incision and skin closure. There were 688 patients included in the study, of whom 24 (3.5%) developed an SSI within 30 days after surgery. In uni- and multivariable analysis, an increased mean door opening frequency during cardiac surgery was associated with higher risk for consecutive SSI (adjusted hazard ratio per 5-unit increment, 1.49; 95% confidence interval, 1.11-2.00; P = .008). The observed effect was driven by internal OR door openings toward the clean instrument preparation room.

CONCLUSIONS

Frequent door openings during cardiac surgery were independently associated with an increased risk for SSI. This finding warrants further study to establish a potentially causal relationship between OR door openings and the occurrence of SSI.

Perceived Need for Psychosocial Support After Aortic Dissection: Cross-Sectional Survey

Background

The gold standard management of aortic dissection, a life-threatening condition, includes multidisciplinary approaches. Although mental distress following aortic dissection is common, evidence-based psychosocial interventions for aortic dissection survivors are lacking.

Objective

The aim of this study is to identify the perceived psychosocial needs of aortic dissection survivors by surveying patients, their relatives, and health professionals to inform the development of such interventions.

Methods

This study used a cross-sectional survey and collected responses from 41 participants (27 patients with aortic dissection, 8 relatives of patients with aortic dissection, and 6 health professionals) on key topics, types of interventions, best timing, anticipated success, and the intended effects and side effects of psychosocial interventions after aortic dissection.

Results

The principal intervention topics were “changes in everyday life” (28/41, 68%, 95% CI 54.5%-82.9%), “anxiety” (25/41, 61%, 95% CI 46.2%-76.2%), “uncertainty” (24/41, 59%, 95% CI 42.9%-73.2%), “tension/distress” (24/41, 59%, 95% CI 43.9%-73.8%), and “trust in the body” (21/41, 51%, 95% CI 35.9%-67.5%). The most commonly indicated intervention types were “family/relative therapy” (21/41, 51%, 95% CI 35%-65.9%) and “anxiety treatment” (21/41, 51%, 95% CI 35%-67.5%). The most recommended intervention timing was “during inpatient rehabilitation” (26/41, 63%, 95% CI 47.6%-77.5%) followed by “shortly after inpatient rehabilitation” (20/41, 49%, 95% CI 32.4%-65%). More than 95% (39/41) of respondents anticipated a benefit from psychosocial interventions following aortic dissection dissection, expecting a probable improvement in 68.6% (95% CI 61.4%-76.2%) of aortic dissection survivors, a worse outcome for 5% (95% CI 2.9%-7.9%), and that 6% (95% CI 1.8%-10.4%) would have negative side effects due to such interventions.

Conclusions

Our findings highlight a substantial need for psychosocial interventions in aortic dissection survivors and indicate that such interventions would be a success. They provide a basis for the development and evaluation of interventions as part of state-of-the-art aortic dissection management.

Impact of the bicuspid aortic valve on aortic root haemodynamics: three-dimensional computed fluid dynamics simulation

OBJECTIVES

The aim was to evaluate the impact of a bicuspid aortic valve (BAV) on local shear stress and on the pressure profile on the elements of the aortic root (AoR).

METHODS

The experiment setup included a BAV with aortic valve stenosis (n = 5 pigs, 67 ± 3.5 kg) and insufficiency (n = 5 pigs, 66.7 ± 4.4 kg). By implanting 6 high-fidelity microsonometric crystals in each AoR, we determined the 3-dimensional (3D) geometry of the AoR. Experimental and geometric data were used to create a 3D time- and pressure-dependent computed fluid dynamic model of the AoR with the BAV.

RESULTS

3D AoR geometry was determined by AoR tilt (α) and rotation angle (β). Both values were maximal at the end of diastole: 24.41 ± 1.70° (α) and 20.90 ± 2.11° (β) for BAV with stenosis and 31.92 ± 11.51° (α) and 20.84 ± 9.80° (β) for BAV with insufficiency and minimal at peak ejection 23.42 ± 1.65° (α), 20.38 ± 1.61° (β) for stenosis and 26.62 ± 7.86° (α), 19.79 ± 8.45° (β) for insufficiency. In insufficiency, low shear stress of 0-0.08 Pa and moderate pressure (60-80 mmHg) were present. In BAV with stenosis, low shear stress of 0-0.5 Pa and moderate pressure (0-20 mmHg) were present at diastole; at peak ejection high shear stress >2 Pa and elevated pressure of >80 mmHg were present.

CONCLUSIONS

In a BAV with aortic valve stenosis, the haemodynamics are less favourable. The elevated pressure with elevated shear stress may over the long term promote degenerative processes in the leaflets and consequently valve function failure.

Microplegia versus Cardioplexol® in Coronary Artery Bypass Surgery with Minimal Extracorporeal Circulation: Comparison of Two Cardioplegia Concepts

BACKGROUND

The aim of this study is to compare the combined use of the Myocardial Protection System and our microplegia (Basel Microplegia Protocol) with Cardioplexol^® in coronary artery bypass grafting using the minimal extracorporeal circulation.

METHODS

The analysis focused on propensity score matched pairs of patients in whom microplegia or Cardioplexol^® was used. Primary efficacy endpoints were high-sensitivity cardiac troponin-T on postoperative day 1 and peak values during hospitalization. Furthermore, we assessed creatine kinase and creatinine kinase-myocardial type, as well as safety endpoints.

RESULTS

A total of 56 patients who received microplegia and 155 patients who received Cardioplexol^® were included. The use of the microplegia was associated with significantly lower geometric mean (confidence interval) peak values of high-sensitivity cardiac troponin-T (233 ng/L [194-280 ng/L] vs. 362 ng/L [315-416 ng/L]; p = 0.001), creatinine kinase (539 U/L [458-633 U/L] vs. 719 U/L [645-801 U/L]; p = 0.011), and creatinine kinase-myocardial type (13.8 µg/L [9.6-19.9 µg/L] vs. 21.6 µg/L [18.9-24.6 µg/L]; p = 0.026), and a shorter length of stay on the intensive care unit (1.5 days [1.2-1.8 days] vs. 1.9 days [1.7-2.1 days]; p = 0.011). Major adverse cardiac and cerebrovascular events occurred with roughly equal frequency (1.8 vs. 5.2%; p = 0.331).

CONCLUSIONS

The use of the Basel Microplegia Protocol was associated with lower peak values of high-sensitivity cardiac troponin-T, creatinine kinase, and creatinine kinase-myocardial type and with a shorter length of stay on the intensive care unit, as compared with the use of Cardioplexol^® in isolated coronary artery bypass surgery using minimal extracorporeal circulation.

Acute Pulmonary Embolectomy Three Days following a Coronary Artery Bypass Graft Procedure

Pulmonary embolism is very rarely reported early after cardiac surgery, most probably due to full heparinisation during cardiopulmonary bypass. We report a 66-year-old man without thromboembolic history who presented three days after a coronary artery bypass grafting procedure with acute dyspnoea and haemodynamic instability. A CT scan confirmed paracentral bilateral pulmonary embolism requiring an urgent and successful embolectomy. Review of the literature confirms that pulmonary embolism may occur in up to 3% of post-cardiopulmonary bypass patients.

The possibility of pulmonary embolism must be taken into consideration in post-cardiopulmonary bypass patients with acute onset of chest pain and respiratory insufficiency.

Clinical implementation of a novel myocardial protection pathway in coronary artery bypass surgery with minimal extracorporeal circulation

INTRODUCTION

The aim of this study was to report the clinical implementation of the joint use of the Myocardial Protection System (MPS^®) and the minimal extracorporeal circulation system (MiECC), in conjunction with an institutionally refined dose/volume-dependent microplegia in coronary artery bypass grafting (CABG).

METHODS

Patients with isolated CABG surgery were included. The final protocol to achieve cardioplegic arrest consisted of warm blood cardioplegia with 20 mmol potassium (K), 1.6 g magnesium (Mg) and 40 mg lidocaine per liter (L) blood. We prospectively collected intra- and postoperative data to monitor and validate this novel approach.

RESULTS

Eighty patients were operated accordingly. Mean (SD) aortic clamping time and extracorporeal perfusion time were 67.5 (22.6) and 101.1 (31.9) minutes, respectively. Failure to induce cardiac arrest was seen in six patients at the early stage of refinement of the formula. Median (IQR) high -sensitivity cardiac troponin T (hs-cTnT) on the first postoperative day (POD) and peak hs-cTnT were 262.5 ng/L (194.3-405.8) and 265.5 ng/L (194.3-405.8), respectively. Median (IQR) creatine kinase-myocardial type (CK-MB) on POD 1 and peak CK-MB were 14.2 µg/L (10.5-22.7) and 14.2 µg/L (10.7-23.2), respectively. Median (IQR) creatine kinase (CK) on POD 1 and peak CK were 517.5 U/L (389.3-849.8) and 597.5 U/L (455.0-943.0), respectively. No patient died during hospitalization.

CONCLUSIONS

The combination of this cardioplegic formula with MPS^® and MiECC in CABG was safe and feasible. With the final chemical makeup, cardiac arrest was reliably achieved. Remarkably low postoperative cardiac markers indicate shielded cardiac protection during surgery.

Paracrine potential of adipose stromal vascular fraction cells to recover hypoxia-induced loss of cardiomyocyte function

Cell-based therapies show promising results in cardiac function recovery mostly through paracrine-mediated processes (as angiogenesis) in chronic ischemia. In this study, we aim to develop a 2D (two-dimensional) in vitro cardiac hypoxia model mimicking severe cardiac ischemia to specifically investigate the prosurvival paracrine effects of adipose tissue-derived stromal vascular fraction (SVF) cell secretome released upon three-dimensional (3D) culture. For the 2D-cardiac hypoxia model, neonatal rat cardiomyocytes (CM) were cultured for 5 days at < 1% (approaching anoxia) oxygen (O₂ ) tension. Typical cardiac differentiation hallmarks and contractile ability were used to assess both the cardiomyocyte loss of functionality upon anoxia exposure and its possible recovery following the 5-day-treatment with SVF-conditioned media (collected following 6-day-perfusion-based culture on collagen scaffolds in either normoxia or approaching anoxia). The culture at < 1% O ₂ for 5 days mimicked the reversible condition of hibernating myocardium with still living and poorly contractile CM (reversible state). Only SVF-medium conditioned in normoxia expressing a high level of the prosurvival hepatocyte-growth factor (HGF) and insulin-like growth factor (IGF) allowed the partial recovery of the functionality of damaged CM. The secretome generated by SVF-engineered tissues showed a high paracrine potential to rescue the nonfunctional CM, therefore resulting in a promising patch-based treatment of specific low-perfused areas after myocardial infarction.

Aortic valve replacement using autologous pericardium: single centre experience with the Ozaki technique

OBJECTIVE

To assess the clinical implementation and report preliminary results of a novel technique called the Ozaki procedure for stentless aortic valve replacement through reconstruction of the valve leaflets from autologous pericardium.

METHOD

Between September 2015 and May 2017 30 patients (20 males, mean ± standard deviation age 66.83 ± 10.55 years) suffering from aortic stenosis (AS, n = 7), aortic regurgitation (AR, n = 12), or a combination of both (AS/AR, n = 11) were assigned for an Ozaki procedure. The glutaraldehyde-treated autologous pericardium was intraoperatively customised and tailored according to individual sinus measurements and appropriate Ozaki templates (CE marked).

RESULTS

Mean and peak preoperative transvalvular pressure gradients in patients with AS were 46.34 ± 14.71 and 78.00 ± 22.54 mm Hg, respectively and effective orifice area was 0.93 ± 0.26 cm2. Ejection fraction was preserved at 57.37 ± 10.33%. Twenty-four valves were tricuspid and 6 bicuspid; 13 patients had concomitant cardiac surgery (coronary artery bypass graft, mitral valve repair, replacement of ascending aorta). Mean ± SD cross-clamp time for replacement only was 85.18 ± 18.10 minutes and perfusion time 104.76 ± 38.52 minutes. Cusp sizes were 27.76 ± 3.52 mm for the left coronary cusp (CC), 28.20 ± 3.51 mm for the right CC and 29.20 ± 3.34 mm for non-CC. Mean and peak postoperative gradients decreased to 8 ± 3.55 and 14.8 ± 6.21 mm Hg, respectively. Mean length of stay on the intensive care unit was 2.19 ± 2.34 days and in-hospital stay was 8.81 ± 2.04 days after isolated Ozaki procedures. No pacemaker had to be implanted after an isolated Ozaki procedure. Thirty-day mortality was 3.33% (n = 1). After 3 months, no patient presented with aortic stenosis, and regurgitation of the substituted valves was graded nil/trace in 85.71%, mild in 10.71%, and moderate in 3.57% of the patients. Ejection fraction remained unchanged at 58.89 ± 11.29%. No reoperation was required within the first 3 months.

CONCLUSION

This aortic valve replacement technique has become available only recently. In our experience, it can be mastered after a relatively short training period, and has become part of our routine clinical toolbox. The use of autologous pericardium in combination with excellent haemodynamics may have the potential to overcome the structural disadvantages of biological aortic valves, to be beneficial in infective endocarditis, and to represent an alternative for patients with small annuli.

Independent Predictors of the Duration and Overall Burden of Postoperative Delirium After Cardiac Surgery in Adults: An Observational Cohort Study

OBJECTIVE

Postoperative delirium (POD) is a common complication after cardiac surgery and is associated with increased patient morbidity and mortality. The objective of this study was to identify risk factors for long duration and overall burden of POD after cardiac surgery.

DESIGN

One-year, single-center, retrospective, observational cohort study.

SETTING

University hospital.

PARTICIPANTS

Adult patients undergoing cardiac surgery with cardiopulmonary bypass in 2013.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

Patients were screened for POD using the Intensive Care Delirium Screening Checklist. The primary outcome measure was the incidence of POD. Secondary outcome measures were the duration of POD and the area under the curve determined using the Intensive Care Delirium Screening Checklist score over time. Independent predictors of POD were estimated in multivariable logistic regression models. Hospital length of stay, medications, and outcome data also were analyzed. Among the 656 patients included in the cohort, 618 were analyzed. The overall incidence of POD was 39%. Older patient age (odds ratio [95% confidence interval]) 1.06 [1.04-1.09] for an increase of 1 year, p < 0.001); low preoperative serum albumin (1.08 [1.03-1.13] for a decrease of 1 g/L, p < 0.001); a history of atrial fibrillation (2.30 [1.30-4.09], p = 0.004); perioperative stroke (6.27 [1.54-43.64], p = 0.008); ascending aortic replacement surgery (2.99 [1.50-6.05], p = 0.002); longer duration of procedure (1.37 [1.16-1.63] for an increase of 1 hour, p < 0.001); and increased postoperative C-reactive protein concentration (2.16 [1.49-3.16] for a 2-fold increase, p < 0.001) were associated with higher odds of POD. Among patients affected by POD, older age, perioperative stroke, longer procedure time, and increased postoperative C-reactive protein were consistently predictive of longer duration of POD and greater area under the curve.

CONCLUSIONS

Known risk factors for the development of POD after cardiac surgery also are predictive of prolonged duration and high overall burden of POD.

Case report: Open replacement of incomplete semi-circular traumatic ruptures of the ascending and descending aorta

An incomplete traumatic rupture of the ascending aorta is a rare but life-threatening condition. Hence, the assessment of the extent of the injury prior to therapy is crucial. We report a case of a 50-year-old male with traumatic aortic rupture who underwent emergency surgery after the evaluation of computed tomography scan (CT-scan). The surgical treatment involved replacement of the ascending aorta and stent implantation in descending aorta due to its covered rupture.

Prolonged recovery and respiratory depression after fentanyl infusion in a sheep undergoing mitral valve reconstruction

A sheep was anaesthetized for implantation of a novel device (MitroFast®) to replace the posterior leaflet of the mitral valve. Anaesthetic management included a balanced anaesthetic protocol and consisted of propofol or isoflurane combined with fentanyl infusion (0.15–0.4 μg/kg/min). Deliberate hypothermia during cardiopulmonary bypass was set at 34.5–35.5°C. Surgery proceeded uneventfully. Total time of aortic cross-clamping was 35 min and total time on extracorporeal circulation was 60 min. Visual inspection, intracardiac pressure testing and transesophageal echocardiography indicated proper functioning of the device. The anaesthetic period was uneventful, but recovery was prolonged with central nervous and respiratory depression and marked hypoxaemia. Administration of naloxone (1.5 μg/kg, repeated twice at 15–20 min intervals) reversed the central nervous and attenuated the respiratory depressions. An initially low rate of urine production normalized after rewarming and a single intravenous administration of furosemide.

Automated fastener versus manually tied knots in minimally invasive mitral valve repair: impact on operation time and short- term results

Background

This study compares the influence of two different annuloplasty attachment suture applications, namely the use of an automated fastener versus manually tied knots using a traditional knot pusher, on total operation time, on cardiopulmonary-bypass time and on cross-clamp time, and on short-term outcome.

Methods

Sixty patients underwent isolated minimally invasive mitral valve repair in Carpentier Type-II mitral disease with implantation of an annuloplasty ring in combination with correction of the prolapsing leaflet using artificial chords. The first 30 patients after implementation of a novel automated fastener were compared with the last 30 patients corrected with a traditional knot pusher. No significant differences with regard to demographic data (age, gender, NYHA class, ejection fraction, BMI, cardiovascular risk factors) between the two groups were found. All patients received isolated mitral valve repair in the first run. Bretschneider HTK was used for cardioplegic cardiac arrest in all patients.

Results

Transesophageal and transthoracic echocardiography at the end of operation and at discharge revealed no (n = 25), trace (n = 28) or mild (n = 7) residual regurgitation with no evidence of ring dehiscence and without any significant clinical differences between the groups. Cross-clamp, cardiopulmonary-bypass and total- operation time were significantly reduced in the automated fastener group compared to the group using a traditional knot pusher (87.1 ± 17.9 vs. 101.3 ± 17.8; p < 0.01, 138.1 ± 25.6 vs. 152.7 ± 24.9; p < 0.05, and 203.9 ± 31.02 vs. 223.8 ± 29.01; p < 0.01, respectively).

Conclusion

Our short-term results indicate a safe, reliable and fast application of the novel automated fastener device in combination with significant time savings in cardioplegic arrest and cardiopulmonary bypass.

One-year patency control and risk analysis of eSVS®-mesh-supported coronary saphenous vein grafts

Background

The eSVS® external venous nitinol mesh (Kips Bay Medical, Minneapolis, USA) was designed to improve long-term patency of coronary saphenous vein grafts (SVG) by preventing pressure-induced wall stress and reactive neo-intimal hyperplasia. We present one-year-patency rates of meshed SVGs assessed by coronary computed tomographic angiography (cCTA).

Patients and Methods

Data from consecutive patients receiving an eSVS® meshed coronary bypass SVG from 06/2010 to 06/2011 were prospectively collected and analysed post-hoc. Patient characteristics, coronary artery disease, SVG quality, surgery (including number of anastomoses and transit time flow-measurement: TTFM), postoperative course and graft patency by cCTA were recorded. Potential risk factors for meshed graft occlusion were evaluated.

Results

22 patients received an eSVS® mesh (18 isolated CABG, 4 combined with aortic valve replacement). Three patients died prior to the one-year follow-up and were excluded. All 19 surviving patients (mean age 70.4 ± 9.5 years, 3 female) completed a cCTA of all grafts at 12 ± 0.1 months after surgery including 21 meshed SVGs (33 distal anastomoses), 7 unmeshed SVGs (13 distal anastomoses) and 22 arterial grafts (30 distal anastomoses).

Mesh application was safe with patent grafts (by intraoperative TTFM) and perioperative course uneventful in all patients. The average graft/anastomosis number per patient was 2.6 ± 0.5/3.7 ± 0.8. Patency was unrestricted in all arterial and unmeshed SVGs (cCTA). Meshed SVG patency was 85 % (n = 28/33) for distal anastomoses and 76 % (n = 16/21) among meshed SVGs. Four SVGs with single distal anastomosis to the right coronary were completely occluded. One sequential graft to the left coronary was occluded between proximal and first distal anastomosis (see Fig. 1). Patency was independent of target site, coronary run-off, SVG quality and sequential distal grafting. All patients were asymptomatic.

Conclusions

The overall one-year patency rate of eSVS® meshed SVGs/anastomoses was 76 %/85 %. Surgical implantation is safe independently of target site, run-off, vein quality and sequential distal anastomoses. However, graft patency of meshed veins (76 %) was inferior to non-meshed (100 %) or arterial grafts (100 %). Thus our mid-term data do not sustain the concept of improving vein graft patency by external reinforcing with the eSVS® mesh. Further long-term follow-up is warranted.

Rapamycin impairs endothelial cell function in human internal thoracic arteries

Background

Definitive fate of the coronary endothelium after implantation of a drug-eluting stent remains unclear, but evidence has accumulated that treatment with rapamycin-eluting stents impairs endothelial function in human coronary arteries. The aim of our study was to demonstrate this phenomenon on functional, morphological and biochemical level in human internal thoracic arteries (ITA) serving as coronary artery model.

Methods

After exposure to rapamycin for 20 h, functional activity of ITA rings was investigated using the organ bath technique. Morphological analysis was performed by scanning electron microscopy and evaluated by two independent observers in blinded fashion. For measurement of endothelial nitric oxide synthase (eNOS) release, mammalian target of rapamycin (mTOR) and protein kinase B (PKB) (Akt) activation, Western blotting on human mammary epithelial cells-1 and on ITA homogenates was performed.

Results

Comparison of the acetylcholine-induced relaxation revealed a significant concentration-dependent decrease to 66 ± 7 % and 36 ± 7 % (mean ± SEM) after 20-h incubation with 1 and 10 μM rapamycin. Electron microscopic evaluation of the endothelial layer showed no differences between controls and samples exposed to 10 μM rapamycin. Western blots after 20-h incubation with rapamycin (10 nM–1 μM) revealed a significant and concentration-dependent reduction of p (Ser 1177)-eNOS (down to 38 ± 8 %) in human mammary epithelial cells (Hmec)-1. Furthermore, 1 μM rapamycin significantly reduced activation of p (Ser2481)-mTOR (58 ± 11 %), p (Ser2481)-mTOR (23 ± 4 %) and p (Ser473)-Akt (38 ± 6 %) in ITA homogenates leaving Akt protein levels unchanged.

Conclusions

The present data suggests that 20-h exposure of ITA rings to rapamycin reduces endothelium-mediated relaxation through down-regulation of Akt-phosphorylation via the mTOR signalling axis within the ITA tissue without injuring the endothelial cell layer.

Integrity of mechanical aortic valve prostheses explanted after 27 and 23 years

We describe 2 cases of mechanical aortic valve endocarditis and the influence on clinical outcome and prostheses material integrity. One patient required extensive reconstruction due to active endocarditis leading to a "rocking valve". The second case was caused by late aortic dissection following endocarditis. Both valve prostheses showed remarkable material quality and performance in functional assessment and high resolution scanning electron microscopic evaluation after 27 and 23 years of service.

Controlled angiogenesis in the heart by cell-based expression of specific vascular endothelial growth factor levels

Vascular endothelial growth factor (VEGF) can induce normal angiogenesis or the growth of angioma-like vascular tumors depending on the amount secreted by each producing cell because it remains localized in the microenvironment. In order to control the distribution of VEGF expression levels in vivo, we recently developed a high-throughput fluorescence-activated cell sorting (FACS)-based technique to rapidly purify transduced progenitors that homogeneously express a specific VEGF dose from a heterogeneous primary population. Here we tested the hypothesis that cell-based delivery of a controlled VEGF level could induce normal angiogenesis in the heart, while preventing the development of angiomas. Freshly isolated human adipose tissue-derived stem cells (ASC) were transduced with retroviral vectors expressing either rat VEGF linked to a FACS-quantifiable cell-surface marker (a truncated form of CD8) or CD8 alone as control (CTR). VEGF-expressing cells were FACS-purified to generate populations producing either a specific VEGF level (SPEC) or uncontrolled heterogeneous levels (ALL). Fifteen nude rats underwent intramyocardial injection of 10(7) cells. Histology was performed after 4 weeks. Both the SPEC and ALL cells produced a similar total amount of VEGF, and both cell types induced a 50%-60% increase in both total and perfused vessel density compared to CTR cells, despite very limited stable engraftment. However, homogeneous VEGF expression by SPEC cells induced only normal and stable angiogenesis. Conversely, heterogeneous expression of a similar total amount by the ALL cells caused the growth of numerous angioma-like structures. These results suggest that controlled VEGF delivery by FACS-purified ASC may be a promising strategy to achieve safe therapeutic angiogenesis in the heart.

A new cable-tie-based sternal closure device: infectious considerations

OBJECTIVES

To determine the difference in sternal infection and other infectious events between conventional wire and cable-tie-based closure techniques post-sternotomy in a collective of patients after cardiac surgery.

METHODS

The sternal ZipFix™ (ZF) system consists of a biocompatible poly-ether-ether-ketone (PEEK) cable-tie that surrounds the sternum through the intercostal space and provides a large implant-to-bone contact. Between 1 February 2011 and 31 January 2012, 680 cardiac operations were performed via sternotomy at our institution. After the exclusion of operations for active endocarditis and early mortality within 7 days, 95 patients were exclusively closed with ZF and could be compared with 498 who were closed with conventional wires (CWs) during the same period. A multivariable logistic regression analysis, including body mass index, renal impairment and emergency as suspected confounders and inverse propensity weights was performed on the infection rate.

RESULTS

Total infection rate was 6.1%, with a total of 36 diagnosed sternal infections (5 in ZF and 31 in CW). Comparing ZF with CW with regard to sternal infection, there is no statistically significant difference related to the device (odds ratio: 0.067, confidence interval: 0.04-9.16, P=0.72). The propensity modelling provided excellent overlap and the mean propensity was almost the same in both groups. Thus, we have observed no difference in receiving either ZF or CW. No sternal instability was observed with the ZF device, unlike 4/31 patients in the CW group. The overall operation time is reduced by 11 min in the ZF group with identical perfusion and clamping times.

CONCLUSIONS

Our study underlines a neutral effect of the sternal ZipFix™ system in patients regarding sternal infection. Postoperative complications are similar in both sternal closure methods. The cable-tie-based system is fast, easy to use, reliable and safe.

A new cable-tie based sternal closure system: description of the device, technique of implantation and first clinical evaluation

Background

Wire closure still remains the preferred technique despite reasonable disadvantages. Associated complications, such as infection and sternal instability, cause time- and cost-consuming therapies. We present a new tool for sternal closure with its first clinical experience and results.

Methods

The sternal ZipFix^TM System is based on the cable-tie principle. It primarily consists of biocompatible Poly-Ether-Ether-Ketone implants and is predominantly used peristernally through the intercostal space. The system provides a large implant-to-bone contact for better force distribution and for avoiding bone cut through.

Results

50 patients were closed with the ZipFix^TM system. No sternal instability was observed at 30 days. Two patients developed a mediastinitis that necessitated the removal of the device; however, the ZipFix^TM were intact and the sternum remained stable.

Conclusions

In our initial evaluation, the short-term results have shown that the sternal ZipFix^TM can be used safely and effectively. It is fast, easy to use and serves as a potential alternative for traditional wire closure.

Simplified closure of ministernotomy using thermoreactive sternal clips

An increasing number of aortic valve replacements are performed through a ministernotomy. Due to the small incision and partial fixation of the caudal sternum, the traditional wire closure can be complicated and even harmful to the surrounding tissue. In such cases, we recommend the use of nitinol clips for sternal closure. This technique, which we have used in 48 patients, is simple, safe, and fast, and results in excellent outcomes.

Proteome analysis in cardiovascular pathophysiology using Dahl rat model

Dahl salt-sensitive (DS) and salt-resistant (DR) inbred rat strains represent a well established animal model for cardiovascular research. Upon prolonged administration of high-salt-containing diet, DS rats develop systemic hypertension, and as a consequence they develop left ventricular hypertrophy, followed by heart failure. The aim of this work was to explore whether this animal model is suitable to identify biomarkers that characterize defined stages of cardiac pathophysiological conditions. The work had to be performed in two stages: in the first part proteomic differences that are attributable to the two separate rat lines (DS and DR) had to be established, and in the second part the process of development of heart failure due to feeding the rats with high-salt-containing diet has to be monitored. This work describes the results of the first stage, with the outcome of protein expression profiles of left ventricular tissues of DS and DR rats kept under low salt diet. Substantial extent of quantitative and qualitative expression differences between both strains of Dahl rats in heart tissue was detected. Using Principal Component Analysis, Linear Discriminant Analysis and other statistical means we have established sets of differentially expressed proteins, candidates for further molecular analysis of the heart failure mechanisms.

[Surgical treatment options in end-stage heart failure]

Despite significant improvements in pharmacological therapy heart failure is still one of the leading causes for death in the Western World. The gold standard treatment of end-stage heart failure remains cardiac transplantation, but there is a great excess of eligible candidates compared with the low number of suitable donor organs. The variety of surgical organ preserving treatment strategies has significantly increased during the last 20 years, intenting either to delay or even to prevent the need for cardiac transplantation. An individually tailored surgical concept should be considered as an alternative in any heart failure patient who has reached the limits of pharmacologic therapy. This article gives an overview about current and potential future therapeutic options in end-stage heart failure.

Reactive oxygen species mediate functional differences in human radial and internal thoracic arteries from smokers

OBJECTIVE

Smoking not only increases the risk that coronary heart disease will develop but also morbidity and mortality in patients with known coronary atherosclerosis and after coronary artery bypass grafting. Excessive generation of reactive oxygen species (ROS) has been implicated as the final common pathway for the development of endothelial dysfunction in various cardiovascular risk factors. This study assessed the influence of smoking on two different human arteries routinely used as coronary artery bypass graft conduits.

METHODS

Isometric tension was recorded on discarded segments of human left internal thoracic artery (ITA) and the radial artery (RA) from smokers and nonsmokers.

RESULTS

The contractile response to endothelin-1 was significantly stronger in arteries from smokers than in those from nonsmokers. By contrast, endothelium-dependent relaxant responses to acetylcholine were attenuated in RA rings but enhanced in ITA rings from smokers. In additional experiments, 5-(&6)-chloromethyl-2'-7'-dichlorodihydro-fluorescein diacetate (DCDHF) was used to photochemically detect ROS by confocal imaging of intact ITA and RA. Enhanced production of ROS was induced by exposure of tissues to 28 degrees C. While during exposure to 28 degrees C, basal fluorescence emission was unchanged in ITA rings, it increased significantly in RA rings, indicating enhanced formation of ROS in this peripheral artery.

CONCLUSIONS

Data suggest that smoking induces endothelial dysfunction by increasing vascular ROS production. Different levels of endogenous antioxidant enzyme activities and the degree of atherosclerotic changes might modulate physiologic and pharmacologic vasoreactivity and be responsible for decreased graft patency of RA compared with ITA conduits, especially in active smokers.

The role of the sinuses of Valsalva in aortic root flow dynamics and aortic root surgery: evaluation by magnetic resonance imaging

BACKGROUND AND AIM OF THE STUDY

Combined replacement of the aortic valve and ascending aorta using a composite graft represents the standard treatment for dilated aortic root with concomitant structural damage of the aortic valve, especially when the aortic valve cannot be preserved. Unfortunately, hemodynamic changes associated with prosthetic replacement of the aortic root have not been fully elucidated. The study aim was to compare hemodynamics within the replaced aortic root using either a prosthetic vascular graft with bulges mimicking the sinuses of Valsalva and including a stented pericardial valve, or a straight xenopericardial conduit and a stentless porcine valve.

METHODS

Between July 2004 and March 2006, a total of 35 patients (mean age 65.2 years: range: 32-80 years) was enrolled into the present study. Aortic root replacement was performed in nine patients with a Valsalva graft (Gelweave Valsalva; Vascutek, Renfrewshire, UK) including a stented pericardial valve, and in 19 patients with a xenopericardial conduit containing a stentless porcine valve. All patients underwent postoperative magnetic resonance imaging (MRI). A control group of seven patients allowed for comparison with native aortic root hemodynamics.

RESULTS

Maximum flow-velocity above the aortic valve as one marker of compliance of the aortic root was slightly higher in patients with a Valsalva graft compared to native aortic roots (1.9 m/s versus 1.3 m/s, p = 0.001), but was significantly lower than in patients with the xenopericardial graft without neo-sinuses (1.3 m/s versus 2.4 m/s, p < 0.001).

CONCLUSION

The pre-shaped bulges in the prosthetic Valsalva graft effectively mimic the native sinuses of Valsalva, improve compliance of the aortic root, and result in a more physiologic flow pattern, as demonstrated by postoperative MRI.

Arterial access through the right subclavian artery in surgery of the aortic arch improves neurologic outcome and mid-term quality of life

BACKGROUND

We have shown that selective antegrade cerebral perfusion improves mid-term quality of life in patients undergoing surgical repair for acute type A aortic dissection and aortic aneurysms. The aim of the study was to assess the impact of continuous cerebral perfusion through the right subclavian artery on immediate outcome and quality of life.

METHODS

Perioperative data of 567 consecutive patients who underwent surgery of the aortic arch using deep hypothermic circulatory arrest have been analyzed. Patients were divided into three groups, according to the management of cerebral protection. Three hundred eighty-seven patients (68.3%) had deep hypothermic circulatory arrest with pharmacologic protection with pentothal only, 91 (16.0%) had selective antegrade cerebral perfusion and pentothal, and 89 (15.7%) had continuous cerebral perfusion through the right subclavian artery and pentothal. All in-hospital data were assessed, and quality of life was analyzed prospectively 2.4 +/- 1.2 years after surgery with the Short Form-36 Health Survey Questionnaire.

RESULTS

Major perioperative cerebrovascular injuries were observed in 1.1% of the patients with continuous cerebral perfusion through the right subclavian artery, compared with 9.8% with selective antegrade cerebral perfusion (p < 0.001) and 6.5% in the group with no antegrade cerebral perfusion (p = 0.007). Average quality of life after an arrest time between 30 and 50 minutes with continuous cerebral perfusion through the right subclavian artery was significantly better than selective antegrade cerebral perfusion (90.2 +/- 12.1 versus 74.4 +/- 40.7; p = 0.015).

CONCLUSIONS

Continuous cerebral perfusion through the right subclavian artery improves considerably perioperative brain protection during deep hypothermic circulatory arrest. Irreversible perioperative neurologic complications can be significantly reduced and duration of deep hypothermic circulatory arrest can be extended up to 50 minutes without impairment in quality of life.

Temporary neurological dysfunction after surgery of the thoracic aorta: a predictor of poor outcome and impaired quality of life

BACKGROUND

Transient neurological dysfunction (TND) consists of postoperative confusion, delirium and agitation. It is underestimated after surgery on the thoracic aorta and its influence on long-term quality of life (QoL) has not yet been studied. This study aimed to assess the influence of TND on short- and long-term outcome following surgery of the ascending aorta and proximal arch.

METHODS

Nine hundred and seven patients undergoing surgery of the ascending aorta and the proximal aortic arch at our institution were included. Two hundred and ninety patients (31.9%) underwent surgery because of acute aortic dissection type A (AADA) and 617 patients because of aortic aneurysm. In 547 patients (60.3%) the distal anastomosis was performed using deep hypothermic circulatory arrest (DHCA). TND was defined as a Glasgow coma scale (GCS) value <13. All surviving patients had a clinical follow up and QoL was assessed with an SF-36 questionnaire.

RESULTS

Overall in-hospital mortality was 8.3%. TND occurred in 89 patients (9.8%). As compared to patients without TND, those who suffered from TND were older (66.4 vs 59.9 years, p<0.01) underwent more frequently emergent procedures (53% vs 32%, p<0.05) and surgery under DHCA (84.3% vs 57.7%, p<0.05). However, duration of DHCA and extent of surgery did not influence the incidence of TND. In-hospital mortality in the group of patients with TND compared to the group without TND was similar (12.0% vs 11.4%; p=ns). Patients with TND suffered more frequently from coronary artery disease (28% vs 20.8%, p=ns) and were more frequently admitted in a compromised haemodynamic condition (23.6% vs 9.9%, p<0.05). Postoperative course revealed more pulmonary complications such as prolonged mechanical ventilation. Additional to their transient neurological dysfunction, significantly more patients had strokes with permanent neurological loss of function (14.6% vs 4.8%, p<0.05) compared to the patients without TND. ICU and hospital stay were significantly prolonged in TND patients (18+/-13 days vs 12+/-7 days, p<0.05). Over a mean follow-up interval of 27+/-14 months, patients with TND showed a significantly impaired QoL.

CONCLUSION

The neurological outcome following surgery of the ascending aorta and proximal aortic arch is of paramount importance. The impact of TND on short- and long-term outcome is underestimated and negatively affects the short- and long-term outcome.