Surgery for Infective Endocarditis after Primary Transcatheter Aortic-Valve Replacement-A Retrospective Single-Center Analysis.

Transcatheter aortic-valve replacement (TAVR) is increasingly being used for the treatment of aortic-valve stenosis. Therefore, the total number of patients with an aortic-valve prosthesis is increasing, causing the incidence of prosthetic-valve endocarditis to increase. METHODS: Between March 2016 and July 2019, ten patients underwent surgery due to prosthetic-valve endocarditis after TAVR. They were identified in our institutional database and analyzed. RESULTS: Infective endocarditis was diagnosed 17 ± 16 month after TAVR. Mean age was 79 ± 4.4 years. Microbiological detection showed 6/10 positive blood cultures for enterococcus faecalis. Median EuroScore II was 24.64%. The mean size of the surgically replaced aortic prosthesis was 23.6 ± 1.3 and that of the TAVR was 28.4 ± 2.3 mm. The surgically implanted aortic valves had a mean gradient of 8.5 ± 2.2 mmHg. One patient died in hospital due to septic multiorgan failure. After discharge, all patients survived with a mean follow-up of 9 ± 8 month. CONCLUSIONS: With a rising number of patients after TAVR, prosthetic-valve endocarditis will increasingly occur in patients who were previously considered high or intermediate risk. Our results show that patients with TAVR infective endocarditis can be operated on with good results. Surgical therapy should not be withheld from TAVR patients with infective endocarditis.

Training Cardiac Surgeons: Safety and Requirements.

To analyze whether cardiac surgical residents can perform their first surgeries without compromising patients' safety or outcomes, by comparing their performance and results to those of senior surgeons. All documented CABGs conducted between 2002 and 2020 were included. Surgeries were divided according to the experience level of the main surgeon (defined by the number of CABG conducted by him/her) using the following thresholds: 1000; 150; 80 and 35. This resulted in 5 groups: senior surgeons (the reference group); attending surgeons; fellow surgeons; advanced residents and new residents. Primary endpoint was 30 day mortality. Secondary endpoints included a list of intra and post-operative parameters (including in-hospital complications). A multivariable analysis was conducted. 16,486 CABG were conducted by 66 different surgeons over a period of 18 years. Multivariable analysis did not find significant differences between both the primary and the secondary endpoints. Skin-to-skin time correlated significantly with experience level, as new residents needed almost 30% more time than senior surgeons (234 vs 180 minutes). With a suitable supervision by experienced surgeons, patient selection and sufficient resources (longer duration of surgery), surgical residents can perform CABGs with good results and without compromising the patient's outcome.

Negative effect of high-level infrasound on human myocardial contractility: In-vitro controlled experiment.

BACKGROUND: Human exposure to infrasound is increasing due to man-made factors, such as occupational conditions, wind farms and transportation. The concern among the public regarding the safety of infrasound exposure is growing. AIMS: To evaluate whether exposure to infrasound interferes directly with human cardiac function and contributes to pathological processes. SETTING: The University Hospital of Mainz, Germany. METHODS: Human myocardial tissues, obtained from patients undergoing cardiac surgery, were prepared in small muscle samples and stimulated electrically in-vitro for a period of almost two hours under physiological conditions to induce continuous pulsatile contractions and simulating a working human heart. Two samples were obtained from each donor: one was subjected to infrasound for 60 min and the other served as a control. Their contraction forces (CF) and durations (CD) were measured before and after each testing period and their relative changes (CF% and CD%) were calculated and introduced in a multilinear regression model. The following three infrasound levels of exposure were used in this study: 100, 110 and 120 dBz. RESULTS: The measured CF% corresponded negatively with the infrasound level measured in dBz (R2 = 0.631; P = 0.018). The decrease measured almost -11% at 110 dBz and -18% at 120 dBz, after correction for control. The CD on the other hand remained unchanged. CONCLUSIONS: Exposure to high levels of infrasound (more than 100 dBz) interferes with cardiac muscle contractile ability, as early as one hour after exposure. There are numerous additional studies which support this conclusion. These results should be taken into account when considering environmental regulations.

Brain-Derived Neurotrophic Factor Expression and Signaling in Different Perivascular Adipose Tissue Depots of Patients With Coronary Artery Disease.

Background Brain-derived neurotrophic factor (BDNF) is expressed in neuronal and nonneuronal cells and may affect vascular functions via its receptor, tropomyosin-related kinase B (TrkB). In this study, we determined the expression of BDNF in different perivascular adipose tissue (PVAT) depots of patients with established coronary atherosclerosis. Methods and Results Serum, vascular tissue, and PVAT surrounding the proximal aorta (C-PVAT) or internal mammary artery (IMA-PVAT) was obtained from 24 patients (79% men; mean age, 71.7±9.7 years; median body mass index, 27.4±4.8 kg/m2) with coronary atherosclerosis undergoing elective coronary artery bypass surgery. BDNF protein levels were significantly higher in C-PVAT compared with IMA-PVAT, independent of obesity, metabolic syndrome, or systemic biomarkers of inflammation. mRNA transcripts of TrkB, the BDNF receptor, were significantly reduced in aorta compared with IMA. Vessel wall TrkB immunosignals colocalized with cells expressing smooth muscle cell markers, and confocal microscopy and flow cytometry confirmed BDNF receptor expression in human aortic smooth muscle cells. Significantly elevated levels of protein tyrosine phosphatase 1B, a negative regulator of TrkB signaling in the brain, were also observed in C-PVAT. In vitro, inhibition of protein tyrosine phosphatase 1B blunted the effects of BDNF on smooth muscle cell proliferation, migration, differentiation, and collagen production, possibly by upregulation of low-affinity p75 neurotrophin receptors. Expression of nerve growth factor or its receptor tropomyosin-related kinase A did not differ between C-PVAT and IMA-PVAT. Conclusions Elevated expression of BDNF in parallel with local upregulation of negative regulators of neurotrophin signaling in perivascular fat and lower TrkB expression suggest that vascular BDNF signaling is reduced or lost in patients with coronary atherosclerosis.

Direct true lumen cannulation in type A acute aortic dissection: A review of an 11 years' experience.

OBJECTIVES: Direct true lumen cannulation (DTLC) of the aorta is an alternative cardiopulmonary bypass cannulation technique in the context of type A acute aortic dissection (A-AAD). DTLC has been reported to be effective in restoring adequate perfusion to jeopardized organs. This study reports and compares operative outcomes with DTLC or alternative cannulation techniques in a large cohort of patients with A-AAD. METHODS: All patients who underwent surgery for A-AAD between January 2006 and January 2017 in Mainz university hospital were reviewed. The choice of cannulation technique was left to the operating surgeon, however DTLC was our preference in patients who were in state of shock or showed signs of tamponade or hypoperfusion, in cases of potential cerebral malperfusion, as well as in patients who were under resuscitation. RESULTS: A total of 528 patients (63% males, mean age 64±13.8 years) underwent emergency surgery for A-AAD. The DTLC technique was used in 52.4% of patients. The DTLC group of patients had worse clinical status at the time of presentation with more shock, tamponade, true lumen collapse, cerebral and other malperfusion states. New neurologic events were diagnosed in around 8% of patients in each group following surgery, but there was a trend for quicker neurological recovery in the DTLC-group. Early mortality rates, short-term and long-term survival rates did not differ between the two groups. CONCLUSIONS: DTLC is a safe cannulation technique that enables effective antegrade true lumen perfusion in complicated A-AAD scenarios, and is an advantageous addition to the aortic surgeons' armamentarium.

Body Mass Index (BMI) and Its Influence on the Cardiovascular and Operative Risk Profile in Coronary Artery Bypass Grafting Patients: Impact of Inflammation and Leptin.

BACKGROUND: Obesity is related to coronary artery disease (CAD) and worse outcomes in coronary artery bypass graft (CABG) patients. Adipose tissue itself is an endocrine organ that secretes many humoral mediators, such as adipokines, which can induce or reduce inflammation and oxidative stress. OBJECTIVES: We investigate the relationship between the body mass index (BMI), inflammation, and oxidative stress by measuring serum levels of leptin, interleukin-6, and 3-nitrotyrosine in CABG patients and correlate their levels to the cardiovascular and operative risk profiles. METHODS AND RESULTS: 45 men (<75 years) with a median BMI of 29 (21-51) kg/m2, who were diagnosed with CAD and scheduled for elective CABG, were included after applying the following exclusion criteria: prior myocardial infarction, reoperation, female gender, and smoking. Patients' blood samples were taken preoperatively. Several markers were measured. We found significant correlations between leptin and BMI (p < 0.0001) as well as between leptin and 3-nitrotyrosine (p = 0.006). Interleukin-6 was correlated with C-reactive protein (p < 0.0001) and with the incidence of insulin-dependent diabetes mellitus (p = 0.036), arterial hypertension (p = 0.044), reduced left ventricular function (p = 0.003), and severe coronary calcification (p = 0.015). It was also associated with significantly longer extracorporeal bypass time (p = 0.009). Postoperative deep sternal wound infections could be predicted by a higher BMI (p = 0.003) and leptin level (p = 0.001). CONCLUSIONS: There seems to be a correlation between inflammatory processes and cardiovascular morbidity in our cohort. Further, the incidence of deep sternal wound infections is related to a higher BMI and leptin serum level.

T-shaped Transseptal Approach for Mitral Valve Surgery.

We present a T-shaped transseptal approach for mitral valve surgery that makes adequate exposure possible under challenging anatomic and surgical circumstances, hence eliminating the need for forceful retraction on potentially fragile tissues. Particularly suited for patients with complex mitral pathology, it also facilitates juxta-annular transseptal right atrial anchoring, especially in cases of endocarditic anterior mitral annular destruction.

[The Future of Vascular Medicine - Role of 3D Printing]. / Gefäßmedizin in der Zukunft ­ Möglichkeiten mit 3D-Druckverfahren.

Digitalisation is one of the key challenges in current surgery and will impact the future of surgical care as well as upcoming generations of surgeons. 3D printing is a technology that has recently been transferred from industrial prototyping into cardiovascular medicine. The digital model of the anatomical structure which needs to be engineered represents the inherent link of 3D printing to digital medicine. 3D printing technology is able to provide the surgeon with patient-specific models of anatomy and disease for surgical planning and patient informed consent as well as training templates for students and residents, surgical templates and even ready-to-use surgical implants. In our service, we have established a full-inhouse workflow for 3D printing and we currently use this technology for the generation of patient-specific models, training templates and for patient education, as will be presented in this article. Future advances in software solutions, printing polymers and easy-to-handle printers will further propagate and expand the applicability of this technology in cardiovascular medicine.

Contemporary results with the biosynthetic glutaraldehyde denatured ovine collagen graft (Omniflow II) in femoropopliteal position.

OBJECTIVE: The objective of this study was to analyze the outcome of a contemporary series of femoropopliteal bypass operations with the glutaraldehyde denatured polyester mesh-reinforced ovine collagen prosthesis (OCP; Omniflow II [LeMaitre Vascular, Inc, Burlington, Mass]). The experience of two tertiary centers regarding long-term graft function, secondary reinterventions, and biodegeneration of the OCP prosthesis is presented. METHODS: Between January 2006 and January 2014, a series of 205 consecutive operations with the OCP in the femoropopliteal position (54 above knee and 151 below knee) were performed in 194 patients in 202 limbs for disabling claudication (72), chronic critical ischemia (105), acute ischemia (18), popliteal artery aneurysm (4), degeneration of a venous or prosthetic graft (5), and infection of a synthetic bypass graft (1). Grafts were observed with duplex ultrasound scan supplemented by additional angiography in case of recurrent ischemia with prospective documentation of follow-up data in a computerized vascular database. Retrospective analysis of graft patency, limb salvage, and diagnosis of aneurysmal graft degeneration was performed. RESULTS: The 30-day mortality was 3.9%. Early thrombotic bypass occlusion occurred in 8.2% of cases. Four early graft infections could be successfully managed by local treatment with graft preservation. After a mean (median) follow-up of 56 (55) months (range, 1-135 months), primary patency, primary assisted patency, secondary patency, and limb salvage were 71%, 78%, 78%, and 91% for above-knee bypass and 40%, 50%, 63%, and 87% for below-knee bypass at 5 years. Biodegeneration in the form of graft aneurysm or graft stenosis was detected in 26 grafts (12.6%), resulting in secondary open or endovascular procedures in 16 cases. CONCLUSIONS: The OCP provides satisfactory medium- and long-term patency and limb salvage in the femoropopliteal position. Aneurysmal degeneration or graft stenosis may develop over time, demanding lifelong duplex ultrasound surveillance and secondary intervention if needed. Its possible infection-resistant behavior in a contaminated field combined with an acceptable graft patency and limb salvage justifies the use of this graft in the absence of autologous vein.

Early LVAD Implantation in a Patient with Left Ventricular Failure after Aortic Dissection with Left Main Stem Involvement.

BACKGROUND: Coronary involvement in aortic dissection heralds a poor outcome. Involvement of the left main stem may lead to left ventricular (LV) failure requiring mechanical circulatory support. CASE REPORT: A staged approach was applied in a 24-year-old female who suffered extensive infarction due to aortic dissection with left main stem involvement. After replacement of the ascending aorta and grafting of the left internal thoracic artery to the left anterior descending artery following a failed attempt at reconstruction of the left coronary ostium, she failed to wean from cardiopulmonary bypass (CPB) and underwent implantation of an extracorporeal life support (ECLS) system as a bridge to decision. Subsequent implantation of a left ventricular assist device (LVAD) as a bridge to recovery/transplantation was followed by an uneventful further course. CONCLUSIONS: Our experience suggests that early implantation of a ventricular assist device (VAD) as bridge to recovery/transplantation is an alternative to prolonged ECLS in patients who suffered extensive myocardial infarction in the course of aortic dissection.

The Effect of Ivabradine on the Human Atrial Myocardial Contractility in an In Vitro Study.

PURPOSE: Ivabradine has emerged as a new antiarrhythmic agent that could compete with the traditional ones, such as beta-blockers. This experimental study aims to ascertain whether ivabradine directly interferes with the myocardial contractility in an in vitro environment. METHODS: Myocardial tissues from the right atrial appendages of patients undergoing cardiac surgery were dissected to obtain 40 specimens from 20 patients (length: 3 mm), which were exposed to electrical impulses at a frequency of 75 bpm for 30 min to reach a steady state. Specimens were then categorised into four groups (each including five patients). The first group was the control, whereas the second, third, and fourth were treated with 60 nM, 200 nM, and 2 µM ivabradine, respectively. We assessed five different contraction parameters before and after a 15 min treatment and calculated their relative changes, which were then compared to the control group. RESULTS: Ivabradine has affected the force of contraction significantly in vitro (p=0.009). However, force of contraction decreased in both the control group (93.5 ± 4.7%) and the second group (94.1 ± 4.5%, p=0.8) and force of contraction remained unchanged in the third group (101.0 ± 4.1%, p=0.24) and increased significantly in the fourth group (108.9 ± 11.6%, p=0.008). There was no change in other contraction parameters, such as passive tension force (97.1 ± 5.1%, p=0.368), duration of contraction (99.1 ± 4.3%, p=0.816), time to peak (96.6 ± 3.0%, p=0.536), and time to relaxation (101.2 ± 7.0%, p=0.564). CONCLUSIONS: Ivabradine did not interfere with the contractile behaviour of human atrial tissue when it was used in therapeutic dosages in vitro. However, it increased the contractility slightly, when it was used in supratherapeutic dosage.

Giant right atrial myxoma: A rare cause of cardiovascular collapse.

We report the case of a patient with a giant right atrial myxoma that remained clinically silent until it almost completely obliterated the right atrium, prolapsed into the right ventricle and obstructed the tricuspid valve inflow. This case illustrates the importance of rapid surgical intervention in the setting of acute heart failure caused by tumor masses obliterating heart valves or cardiac chambers.

Survival and reinterventions after isolated proximal aortic repair in acute type A aortic dissection.

OBJECTIVES: Conventional treatment for acute type A dissection is the replacement of the ascending aorta. This study demonstrates the results of a conventional approach with isolated proximal repair combined with concomitant endovascular procedures. METHODS: Replacement of the ascending aorta with or without an open distal anastomosis was defined as isolated proximal repair and was performed in 562/588 patients between January 2004 and June 2017. A total of 68% were DeBakey type I and 32% were DeBakey type II aortic dissections. Concomitant procedures were thoracic endovascular aortic repair (3.6%); visceral, renal and iliac stents (2%); and peripheral bypasses (1.1%). Mean follow-up was 4.6 ± 3.5 years with a 98% follow-up rate. Early and long-term survival, reintervention rates and risk factors were analysed. RESULTS: Overall, the in-hospital mortality rate was 10.7%, 5.6% in DeBakey type II and 13% in DeBakey type I aortic dissection (P = 0.008). Risk factors for in-hospital mortality were age [odds ratio (OR) 1.03], chronic obstructive lung disease (OR 3.98), coronary artery disease (OR 2.19), Penn class BC (OR 15.41) and cardiopulmonary bypass time (OR 1.01). The 5- and 10-year survival rates, including in-hospital mortality, were 71% and 54% for type I and 73% and 65% for type II aortic dissection, respectively (P = 0.14). Freedom from reintervention after 5 and 10 years was 96% and 94% for DeBakey type II aortic dissection and 86% and 78% for type I (P < 0.001). CONCLUSIONS: Combined with concomitant endovascular procedures, good short- and long-term results can be achieved in DeBakey type I and II aortic dissection. The reintervention rate is higher in DeBakey type I but can be managed open and endovascularly with good results.

Juxta-annular right atrial anchoring of prosthetic mitral valves in endocarditis with anterior annulus destruction†.

Destruction of the mitral annulus is associated with poor outcomes. We present the treatment of endocarditis using a technique that enables secure anchoring of prosthetic valves where the anterior part of the mitral annulus is severely disrupted. It was used in 5 patients. Follow-up at 10 ± 4 months showed the valves intact without recurrence of endocarditis. Mortality was limited to 1 patient who died of non-cardiac causes. We conclude that partial right atrial anchoring is a useful bail-out and enables favourable outcomes in patients with extensive loss of the (peri)annular tissue due to endocarditis.

Development and evaluation of 3-dimensional printed models of the human tracheobronchial system for training in flexible bronchoscopy.

OBJECTIVES: Training and assessment of proper skills in flexible bronchoscopy are major educational goals for cardiothoracic residents. Therefore, we developed 3-dimensional (3D) printed models of the human tracheobronchial system for training and assessment of cardiothoracic residents in flexible bronchoscopy. METHODS: Three models of normal (size/shape) human tracheobronchial anatomy were generated using a commercially available 3D printer. Ten residents (inexperienced: Group 1; experienced: Group 2) participated in this study with an experimental setting of initial assessment (Model 1), training (15 min, Model 2) and post-training assessment (Model 3). The time needed for flexible bronchoscopy assessment of randomly assigned ostia was recorded before and after training. Additionally, the time for retrieval of a foreign body from the tracheobronchial system was measured before and after training. RESULTS: The average time for intubation of a given ostium (Model 1) at initial assessment was 88 s for Group 1 and 38 s for Group 2 (P < 0.0001). Following training, there was a significant reduction in time for intubation of a given ostium (Model 3) in both groups (P < 0.0001). However, the initial difference between experienced and inexperienced residents was no longer present following training. Additionally, the time for retrieval of a foreign body (cotton wool plug) from the tracheobronchial system was significantly reduced following training in both groups. CONCLUSIONS: Accurate models of the human tracheobronchial system can be generated from representative patient images using 3D engineering software and 3D printing technology. With these models, residents can be effectively trained in flexible bronchoscopy with significant improvement in their proficiency and handling capability.

A low threshold to ECG-gated repeat CTA reduces the risk of false-positive diagnosis of type A dissection in interhospital referrals: a case series study.

BACKGROUND: False-positive diagnosis of acute Stanford type A aortic dissection (AAD) on computed tomography angiography (CTA) is still an issue and may lead to substantial consequences. Given that electrocardiography (ECG)-gated CTA provides greater diagnostic safety, it may be assumed that interhospital referrals with a diagnosis of AAD based on non-ECG-gated pre-referral CTA carry an elevated risk of false-positive diagnosis. PATIENTS AND METHODS: We reviewed a series of patients in whom a diagnosis of AAD based on non-ECG-gated pre-referral CTA was subsequently proven false by ECG-gated CTA. The artifacts that gave rise to the misdiagnosis, as well as the diagnostic pathways followed and the consequences of false-positive diagnosis were investigated. RESULTS: In 5 patients, ECG-gated repeat CTA revealed artifacts in the pre-referral scans that had led to false-positive diagnosis and referral for emergent surgery. In the first case, the patient proceeded to surgery. In 4 subsequent cases, ECG-gated CTA was ordered because a false-positive diagnosis was suspected. We found that ECG-gated CTA rather than echocardiography provided sufficient information to rule out AAD in each of these cases. Comparison between pre-referral non-ECG-gated scans and ECG-gated repeat CTA demonstrated the wide range of artifacts that may give rise to a diagnosis of AAD. CONCLUSION: Patient condition permitting, the threshold to ECG-gated repeat CTA should be low when doubt arises with regard to a diagnosis of AAD based on non-ECG-gated CTA in interhospital referrals.

Repair of TEVAR-Associated Type A Dissection in the Elderly Is Possible With Reasonable Morbidity and Mortality.

BACKGROUND: Type A aortic dissection (AAD) is a devastating complication of thoracic endovascular repair (TEVAR). In elderly patients, surgery for AAD carries considerable morbidity and mortality. Repair of AAD after previous TEVAR is an even greater challenge as it usually requires the arch to be addressed and a preexisting stent graft to be included into the aortic repair. METHODS: A case series of 5 elderly patients who presented with acute AAD after previous TEVAR was reviewed. In 4 cases, there was retrograde AAD with involvement of the arch and stent graft. In 1 patient, intraoperative inspection showed no involvement of the arch. Three underwent ascending and subtotal arch replacement in moderate hypothermic circulatory arrest with selective cerebral perfusion. In 1 case, concomitant tricuspid valve repair was performed. The patient without involvement of the arch underwent emergent replacement of the ascending aorta in deep hypothermic circulatory arrest, and in the oldest, aged 88 years, surgery was limited to wrapping of the ascending aorta as an on-pump beating salvage procedure. RESULTS: Four (80%) of 5 patients survived and were discharged after an intensive care unit stay of 17.45 ± 15.98 days and a hospital stay of 26.0 ± 10.98 days. Mortality was 20%. All survivors were discharged with appropriate rehabilitation potential and without lasting neurological disabilities.

Aerococcus urinae Mitral Valve Endocarditis-Related Stroke: A Case Report and Literature Review.

Background. Aerococcus urinae is a rare causative pathogen of infective endocarditis that results in a high risk of embolic events. The mortality rate for A urinae endocarditis is high. Old age and underlying urologic conditions are the best-known risk factors for infection. Case Description. We report the clinical course of the disease in a 49-year-old man who presented symptoms of a urinary tract infection. A few days later, transthoracic echocardiography showed a conspicuous mitral valve with myxomatous alterations. Following the detection of a cerebral embolism with associated stroke symptoms, as well as at the beginning of cardiac failure, the emergency indication for the surgical treatment of mitral valve endocarditis was given. On the second day following the operation, circulatory collapse rapidly developed. Following an unsuccessful attempt at cardiopulmonary resuscitation, the patient died. Review of the Literature. From 1991 to 2017, 29 cases of A urinae-induced endocarditis have been described in PubMed and Medline. One or 2 new cases are published annually. We review all reported cases of A urinae endocarditis, with an emphasis on the predisposing factors, course, and outcomes of the disease. Conclusion. A urinae endocarditis is a rare disease primarily affecting elderly men with urinary tract pathologies and comorbidities. The course of the disease is severe, and the outcome is often fatal. A 16S rDNA polymerase chain reaction investigation of bacterial genome provides proof of the presence of A urinae. Because of the high risk of embolism, rapid treatment should focus on the diseased heart valve. Based on existing data and the experience gained from handling cases, treatment with ß-lactam and aminoglycosides is recommended. It is also recommended that operative therapy take place as soon as possible.