同期施行冠状动脉搭桥和心脏瓣膜手术的体外循环

目的总结和分析同期施行冠状动脉搭桥和心脏瓣膜手术的体外循环方法。方法125例患者分为3组:M组(冠脉病变及二尖瓣病变)75例,A组(冠脉病变及主动脉瓣病变)34例,D组(冠脉病变及二尖瓣和主动脉瓣病变)16例。心肌保护采用4:1冷含血停搏液,应用单纯顺灌、顺灌逆灌结合、顺灌桥灌结合、顺逆灌和桥灌结合技术。结果术中转流平稳,血流动力学稳定,监测指标均在正常范围,无手术死亡。结论同期施行冠状动脉搭桥和心脏瓣膜手术,术中良好的心肌保护方法和合理的体外循环灌注是保证手术顺利成功的重要因素。     

Novel imaging strategies for the detection of prosthetic heart valve obstruction and endocarditis

Prosthetic heart valve (PHV) dysfunction remains difficult to recognise correctly by two-dimensional (2D) transthoracic and transoesophageal echocardiography (TTE/TEE). ECG-triggered multidetector-row computed tomography (MDCT), 18-fluorine-fluorodesoxyglucose positron emission tomography including low-dose CT (FDG-PET) and three-dimensional transoesophageal echocardiography (3D-TEE) may have additional value. This paper reviews the role of these novel imaging tools in the field of PHV obstruction and endocarditis.For acquired PHV obstruction, MDCT is of additional value in mechanical PHVs to differentiate pannus from thrombus as well as to dynamically study leaflet motion and opening/closing angles. For biological PHV obstruction, additional imaging is not beneficial as it does not change patient management. When performed on top of 2D-TTE/TEE, MDCT has additional value for the detection of both vegetations and pseudoaneurysms/abscesses in PHV endocarditis. FDG-PET has no complementary value for the detection of vegetations; however, it appears more sensitive in the early detection of pseudoaneurysms/abscesses. Furthermore, FDG-PET enables the detection of metastatic and primary extra-cardiac infections. Evidence for the additional value of 3D-TEE is scarce.As clinical implications are major, clinicians should have a low threshold to perform additional MDCT in acquired mechanical PHV obstruction. For suspected PHV endocarditis, both FDG-PET and MDCT have complementary value.     

VALVE MORPHOLOGY OF SYNEDRA GOULARDI (BACILLARIOPHYCEAE)1

Specimens of Synedra goulardi Bréb. from samples taken in Costa Rica were acid cleaned and examined by light and scanning electron microscopy. This linear-lanceolate diatom displays an unusual pattern of markings in its central area which have been mistaken as striae but are actually internal costae. As is typical for members of its genus and that of many other genera in the Fragilariaceae, S. goulardi possesses non-stalked labiate processes, apical pore fields and a lack of marginal spines. There is a great deal of variability in the striae of the genus, ranging from single rows of puncta to areolate striae. Synedra goulardi has double punctate striae. The presence of fossil forms (Neogene) with single punctate striae suggest this may be a primitive condition in the genus.     

Intérêt diagnostique de la TEP-TDM au 18F-FDG dans le diagnostic d’endocardite infectieuse sur valve native

BackgroundNative valve endocarditis (NVE) is a rare but serious disease. The prognosis depends on the rapidity of diagnosis, and is currently based on modified Duke criteria, where echocardiography has a key role but may lack sensitivity if valves are calcified. For prosthetic valves, the European Society of Cardiology 2015 recommendations added ¹⁸F-FDG PET/CT as a major imaging criterion as well as for extension assessment. This study evaluated the diagnostic accuracy of ¹⁸F-FDG PET/CT in NVE and in extension assessment.MethodsThis retrospective study involved 59 patients suspected of NVE at Bordeaux university hospital between 2011 and 2019 and received ¹⁸F-FDG PET/CT. The final diagnosis was established according to Duke criteria after 3 months of management. Infective endocarditis (IE) was assessed in the initial phase according to the Duke criteria. All PET/CTs were blindly reviewed jointly by a junior and senior nuclear-medicine physician.ResultsIn total, 59 patients were included. At 3 months, 26 patients had definite IE, 22 had rejected IE, and 11 possible IE. Twelve patients had positive PET/CT results. The sensitivity of the modified Duke criteria in the initial phase was 77% and the specificity was 81%. When combined with ¹⁸F-FDG PET/CT, the sensitivity of the Duke criteria increased to 96% and the specificity was 81%. The sensitivity of ¹⁸F-FDG PET/CT alone was 46%. All three patients with perivalvular abscess had positive PET/CT results. Of the 22 patients with NVE definite at 3 months, fourteen (54%) had at least one septic embolism diagnosed on PET/CT.ConclusionsThe implementation of ¹⁸F-FDG PET/CT with modified Duke criteria increased the sensitivity for NVE diagnosis in the initial phase and contributed to IE extension assessment. It may contribute to making the diagnosis of a local cardiac complication.     

Changes in demographics,treatment and outcomes in a consecutive cohort who underwent transcatheter aortic valve implantation between 2005 and 2020

IntroductionTranscatheter aortic valve implantation (TAVI) has matured to the treatment of choice for most patients with aortic stenosis (AS). We sought to identify trends in patient and procedural characteristics, and clinical outcomes in all patients who underwent TAVI between 2005 and 2020.MethodsA single-centre analysis was performed on 1500 consecutive patients who underwent TAVI, divided into three tertiles (T) of 500 patients treated between November 2005 and December 2014 (T1), January 2015 and May 2018 (T2) and June 2018 and April 2020 (T3).ResultsOver time, mean age and gender did not change (T1 to T3: 80, 80 and 79 years and 53%, 55% and 52% men, respectively), while the Society of Thoracic Surgeons risk score declined (T1: 4.5% to T3: 2.7%, p < 0.001). Use of general anaesthesia also declined over time (100%, 24% and 1% from T1 to T3) and transfemoral TAVI remained the default approach (87%, 94% and 92%). Median procedure time and contrast volume decreased significantly (186, 114 and 56 min and 120, 100 and 80 ml, respectively). Thirty-day mortality (7%, 4% and 2%), stroke (7%, 3% and 3%), need for a pacemaker (19%, 22% and 8%) and delirium (17%, 12% and 8%) improved significantly, while major bleeding/vascular complications did not change (both approximately 9%, 6% and 6%). One-year survival was 80%, 88% and 92%, respectively.ConclusionOver our 15 years’ experience, patient age remained unchanged but the patient risk profile became more favourable. Simplification of the TAVI procedure occurred in parallel with major improvement in outcomes and survival. Bleeding/vascular complications and the need for pacemaker implantation remain the Achilles’ heel of TAVI.Supplementary InformationThe online version of this article (10.1007/s12471-022-01662-2) contains supplementary material, which is available to authorized users.     

Finite element analysis of the biomechanical interaction between coronary sinus and proximal anchoring stent in coronary sinus annuloplasty

Recent clinical studies of the percutaneous transvenous mitral annuloplasty (PTMA) devices have shown a short-term reduction of mitral regurgitation after implantation. However, adverse events associated with the devices such as compression and perforation of vessel branches, device migration and fracture were reported. In this study, a finite element analysis was carried out to investigate the biomechanical interaction between the proximal anchor stent of a PTMA device and the coronary sinus (CS) vessel in three steps including: (i) the stent release and contact with the CS wall, (ii) the axial pull t the stent connector and (iii) the pressure inflation of the vessel wall. To investigate the impact of the material properties of tissues and stents on the interactive responses, the CS vessel was modelled with human and porcine material properties, and the proximal stent was modelled with two different Nitinol materials with one being stiffer than the other. The results indicated that the vessel wall stresses and contact forces imposed by the stents were much higher in the human model than the porcine model. However, the mechanical differences induced by the two stent types were relatively small. The softer stent exhibited a better fatigue safety factor when deployed in the human model than in the porcine model. These results underscored the importance of the CS tissue mechanical properties. Vessel wall stress and stent radial force obtained in the human model were higher than those obtained in the porcine model, which also brought up questions as to the validity of using the porcine model to assess device mechanical function. The quantification of these biomechanical interactions can offer scientific insight into the development and optimisation of the PTMA device design.     

Deregulation of TNF expression can also cause heart valve disease

High levels of the pro-inflammatory cytokine tumour necrosis factor (TNF) have been associated with many diseases including rheumatoid arthritis (RA), ankylosing spondylitis (AS), inflammatory bowel disease (IBD) and psoriasis.Although it has been clear for twenty-five years that TNF plays a major role in RA and AS, two major questions remain unanswered: (1) What mechanism underlies the loss of control of TNF levels in patients? (2) How does TNF exert its detrimental effects? Nonetheless, biological anti-TNF drugs have become the most successful treatment of these conditions with a third of patients entering remission, and the global market for biological TNF inhibitors is now estimated at around US$35 billions. However, their use is limited by their cost, the fact that they need to be injected, non-negligible side effects and the development of resistance due to the protein (thus antigenic) nature of these TNF inhibitors. It looks inevitable that new approaches to lower the amount of TNF should be considered. To do this, a better understanding of the regulation of TNF expression is necessary.     

Computational simulations of flow dynamics and blood damage through a bileaflet mechanical heart valve scaled to pediatric size and flow

Despite pressing needs, there are currently no FDA approved prosthetic valves available for use in the pediatric population. This study is performed for predictive assessment of blood damage in bileaflet mechanical heart valves (BMHVs) with pediatric sizing and flow conditions. A model of an adult-sized 23 mm St. Jude Medical (SJM) Regent^™ valve is selected for use in simulations, which is scaled in size for a 5-year old child and 6-month old infant. A previously validated lattice-Boltzmann method (LBM) is used to simulate pulsatile flow with thousands of suspended platelets for cases of adult, child, and infant BMHV flows. Adult BMHV flows demonstrate more disorganized small-scale flow features, but pediatric flows are associated with higher fluid shear stresses. Platelet damage in the pediatric cases is higher than in adult flow, highlighting thrombus complication dangers of pediatric BMHV flows. This does not necessarily suggest clinically important differences in thromboembolic potential. Highly damaged platelets in pediatric flows are primarily found far downstream of the valve, as there is less flow recirculation in pediatric flows. In addition, damage levels are well below expected thresholds for platelet activation. The extent of differences here documented between the pediatric and adult cases is of concern, demanding particular attention when pediatric valves are designed and manufactured. However, the differences between the pediatric and adult cases are not such that development of pediatric sized valves is untenable. This study may push for eventual approval of prosthetic valves resized for the pediatric population. Further studies will be necessary to determine the validity and potential thrombotic and clinical implications of these findings.