Myocardial Afterload Is a Key Biomechanical Regulator of Atrioventricular Myocyte Differentiation in Zebrafish

Heart valve development is governed by both genetic and biomechanical inputs. Prior work has demonstrated that oscillating shear stress associated with blood flow is required for normal atrioventricular (AV) valve development. Cardiac afterload is defined as the pressure the ventricle must overcome in order to pump blood throughout the circulatory system. In human patients, conditions of high afterload can cause valve pathology. Whether high afterload adversely affects embryonic valve development remains poorly understood. Here we describe a zebrafish model exhibiting increased myocardial afterload, caused by vasopressin, a vasoconstrictive drug. We show that the application of vasopressin reliably produces an increase in afterload without directly acting on cardiac tissue in zebrafish embryos. We have found that increased afterload alters the rate of growth of the cardiac chambers and causes remodeling of cardiomyocytes. Consistent with pathology seen in patients with clinically high afterload, we see defects in both the form and the function of the valve leaflets. Our results suggest that valve defects are due to changes in atrioventricular myocyte signaling, rather than pressure directly acting on the endothelial valve leaflet cells. Cardiac afterload should therefore be considered a biomechanical factor that particularly impacts embryonic valve development.

Residual Bioprosthetic Valve Immunogenicity: Forgotten, Not Lost

Despite early realization of the need to control inherent immunogenicity of bioprosthetic replacement heart valves and thereby mitigate the ensuing host response and its associated pathology, including dystrophic calcification, the problem remains unresolved to this day. Concerns over mechanical stiffness associated with prerequisite high cross-link density to effect abrogation of this response, together with the insinuated role of leaching glutaraldehyde monomer in subsequent dystrophic mineralization, have understandably introduced compromises. These have become so entrenched as a benchmark standard that residual immunogenicity of the extracellular matrix has seemingly been relegated to a very subordinate role. Instead, focus has shifted toward the removal of cellular compartment antigens renowned for their implication in the failure of vascularized organ xenotransplants. While decellularization certainly offers advantages, this review aims to refocus attention on the unresolved matter of the host response to the extracellular matrix. Furthermore, by implicating remnant immune and inflammatory processes to bioprosthetic valve pathology, including pannus overgrowth and mineralization, the validity of a preeminent focus on decellularization, in the context of inefficient antigen and possible residual microbial remnant removal, is questioned.

Epidemiological aspects of the aortic valve pathology

The dynamics of the structure of aortic valve pathology over the thirty-year (19912020) period of operation of the cardiac surgery hospital of the first department and the clinic of surgery for advanced training of doctors of the Military Medical Academy named after S.M. Kirov is evaluated. 849 cases of aortic valve replacement were retrospectively studied (626 (74%) men, 223 (26%) women). The average age of the patients was 51.8 9.7 years. It was established that the main causes of aortic valve damage were rheumocarditis, calcified aortic stenosis, infectious endocarditis and congenital heart disease in the form of a bicuspid aortic valve. A significant decrease in the incidence of rheumatism as a cause of aortic malformation was revealed from 36% in the period from 1991 to 2000 to 13% in the period from 2011 to 2020. The frequency of calcified aortic stenosis during this period, on the contrary, increased from 30% to 70%, respectively. At the same time, the relationship between the increase in life expectancy of the population of the Russian Federation and the frequency of occurrence of calcified aortic stenosis is traced. This is due to a long asymptomatic period that characterizes the natural course of this pathology, as a result of which the clinical manifestations of this pathology manifest, as a rule, only in old age. During the study period, an increase in the average age of patients who needed aortic valve replacement was also noted. If in the last decade of the twentieth century. it was 41.5 years, then in the period from 2011 to 2020, the average age of patients who needed aortic valve replacement increased to 61.5 years. Thus, over the past thirty years, there has been a significant change in the structure of the pathology of the aortic valve. Calcified aortic stenosis has become the most common cause of prosthetics of aortic malformation, against the background of a significant decrease in the frequency of rheumatic genesis of aortic valve damage.

Surgical Options for Pulmonary Valve Pathology in the Current Era

Pulmonary valve pathology occurs mostly in the settings of congenital heart disease whether primary or as the result of repair of a variety of congenital heart defects. Acquired pulmonary valve disorders, albeit rare, can occur in the settings of endocarditis, tumors, carcinoid syndrome, or rheumatic fever. Surgical options include repair and replacement of pulmonary valve. Several options for replacement are available, which can be tailored based on the patient’s clinical profile and the primary valve pathology. In this chapter, we present the surgical options that are currently available for pulmonary valve disorders and the current outcomes.

Concomittant use of Sapien 3 Transcatheter Valve for Severe MAC with Intuity Elite Rapid Deployment Valve for Aortic Stenosis

Background-Concomitant double valve pathology in the presence of severe MAC poses significant technical challenges when planning surgical intervention. With continued evolution of valve prosthesis, innovative techniques can be considered with the potential for additional therapeutic benefit. Case presentation-We present a novel technique of using a rapid deployment surgical aortic valve in combination with open surgical transcatheter mitral valve implantation (TMVI) for severe Mitral Annular Calcification (MAC). The Intuity Elite rapid deployment prosthesis (Edwards Lifesciences, Irvine, CA) was used concomitantly with the Sapien 3 (Edwards Lifesciences, Irvine, CA) transcatheter prosthesis trans-atrially on cardiopulmonary bypass in a patient with critical aortic stenosis and moderate-severe mixed mitral valve disease in the setting of severe MAC (off-label use). Conclusions-We demonstrate how both technologies can, not only be accommodated, but indeed complement each other achieving an excellent outcome in a high-risk patient.

Five-year outcomes of the modified Ross surgery in adults: experience from one center

<p><strong>Background.</strong> The Ross operation was first proposed in 1967 by D. Ross, and numerous studies have shown that it has excellent long-term results. However, in some patients, it can lead to late dilatation of the pulmonary autograft, which in turn can contribute to repeat operations. To avoid this complication, technical modifications of the Ross operation have been proposed.<br /><strong>Aim.</strong> To evaluate the immediate and five-year outcomes of the modified Ross surgery in adults.<br /><strong>Methods.</strong> This retrospective study included patients aged 18 years and older with aortic valve lesions who underwent a modified Ross procedure by one surgeon between January 2014 and December 2019. The median follow-up period was 23 (12–68) months.<br /><strong>Results.</strong> The study included 43 adult patients. The average age of the patients was 40.0 ± 11.7 years, and 33 (76.7%) were men. The main cause of aortic valve dysfunction was severe aortic regurgitation (32 patients, 74.4%). Infective endocarditis was diagnosed as a cause of aortic valve pathology in 13 (30.2%) patients. Bicuspid aortic valve was present in 29 cases (67.4%). In two cases (4.7%), mini-sternotomy (‘T-shape’) was performed. Ten (23.2%) patients underwent combined interventions. The median duration of cardiopulmonary bypass was 143 (129–160) minutes, and duration of aortic cross-clamp was 116 (109–131) minutes. The autologous inclusion technique was used in 22 (51.2%) cases and the Dacron inclusion technique in 21 (48.8%) cases. Outcomes included no in-hospital mortality, acute renal failure requiring haemodialysis in three patients (7%), pacemaker implantation in two (4.7%), resternotomy for bleeding and stroke in one patient (2.3%) and perioperative myocardial injury in two (4.7%). The five-year overall survival, freedom from reoperation and freedom from dilatation of the ascending aorta or pulmonary autograft ≥ 5 cm after the modified Ross operation were 97.4%, 100.0% and 100.0%, respectively.<br /><strong>Conclusion.</strong> Modified Ross surgery in adults has excellent immediate outcomes with no in-hospital mortality. The five-year overall survival, freedom from reoperation and freedom from aortic dilatation or pulmonary autograft were 97.4%, 100.0% and 100.0%, respectively.</p><p>Received 15 February 2021. Revised 3 June 2021. Accepted 4 June 2021.</p><p><strong>Funding:</strong> The study did not have sponsorship.</p><p><strong>Conflict of interest:</strong> The authors declare no conflicts of interests.</p><p><strong>Contribution of the authors</strong><br />Conception and study design: I.I. Chernov, S.T. Enginoev, D.A. Kondratyev, D.Yu. Kozmin<br />Data collection and analysis: E.R. Aliev, V.V. Demetskaya, D.A. Kondratyev, D.Yu. Kozmin<br />Statistical analysis: S.T. Enginoev<br />Drafting the article: I.I. Chernov, S.T. Enginoev<br />Critical revision of the article: I.I. Chernov, D.G. Tarasov<br />Final approval of the version to be published: I.I. Chernov, S.T. Enginoev, D.A. Kondratyev, D.Yu. Kozmin, V.V. Demetskaya, E.R. Aliev, D.G. Tarasov</p>

Pocket-sized Ultrasound versus Cardiac Auscultation in Diagnosing Cardiac Valve Pathologies: A Prospective Cohort Study

Background: Pocket-sized ultrasound devices are used to perform focused ultrasound studies (POCUS). We compared valve malfunction diagnosis rate by cardiac auscultation to POCUS (insonation), both conducted by medical students. Methods: A prospective cohort study was conducted among patients with and without clinically relevant valve dysfunction. Recruitment to the study group was based on the presence of at least one valve pathology of at least moderate severity identified on recent echocardiography study that was required for clinical reasons. Three final-year medical students examined the patients. Each patient underwent auscultation and a POCUS using a pocket-sized ultrasound machine. Sensitivity was defined as the percentage of patients correctly identified as having a valve disorder. Specificity was defined as correct identification of the absence of valve pathology. Results: The study included 56 patients. In 18 (32%), no valve pathology was found. Nineteen patients (34%) had at least two valvular pathologies. Sixty valve lesions were present in the whole cohort. Students' sensitivity for detecting any valve lesion was 32% and 64% for auscultation and insonation; respectively, specificity was similar. The sensitivity for diagnosing mitral regurgitation, mitral stenosis, and aortic regurgitation rose significantly by using POCUS compared to auscultation alone. When using POCUS, Students identified valve pathologies in 22 cases (39%) from the patients with at least two valve dysfunctions, and none when using auscultation. Conclusions: Final-year medical students' competency to detect valve dysfunction by performing cardiac auscultation is poor. Cardiac ultrasound-focused training significantly improved medical students' sensitivity for diagnosing a variety of valve pathologies.

5 Year Outcomes of Patients With Aortic Structural Valve Deterioration Treated With Transcatheter Valve in Valve – A Single Center Prospective Registry

The Valve-in-Valve (ViV) technique is an established alternative for the treatment of structural bioprosthetic valve deterioration (SVD). Data describing the intermediate term follow up of patients treated with this approach is scarce. We report on our intermediate-term outcomes of patients with SVD in the Aortic position treated with ViV. Included were patients with symptomatic SVD in the aortic position valve who were treated by Valve in valve transcatheter aortic valve implantation (ViV-TAVI) during the years 2010-2019 in our center. Three main outcomes were examined during the follow up period: NYHA functional class, ViV-TAVI hemodynamic per echocardiography, and mortality. Our cohort consisted of 85 patients (mean age 78.8 ± 8.9 years). The indications for aortic ViV were: SVD isolated aortic stenosis in 37.6%, SVD isolated aortic regurgitation in 42.2% and combined valve pathology in 20.0%. Self-expandable and balloon-expandable devices were used in 73 (85.9%) and 12 (14.1%), respectively. Average follow up was 3.7 ± 2.4 years. 95 and 91% of patients were in NYHA functional class I/II at 1 and 5 year follow up respectively. At one year, the mean trans-aortic valve pressure was 15 ± 9 mmHg and rates of ≥ moderate aortic regurgitation were 3.7%. Mortality at one year was 8.6% (95% CI 2.3–14.4) and 31% (95% CI 16.5–42.5) at 5 years. ViV in the aortic position offers an effective and durable treatment option for patient with SVD, with low rates of all-cause mortality, excellent hemodynamic and improved functional capacity at intermediate follow up.

Transient complete heart block: a case report of a rare complication of tricuspid valve infective endocarditis

Background Right-sided tricuspid valve (TV) endocarditis can be difficult to identify and may be under-recognized in the absence of traditional risk factors. While generally identified with aortic valve pathology, infective endocarditis that extends beyond the leaflets of the TV have been reported to cause conduction disease. Case summary We present the case of a 63-year-old patient who presented with haemodynamically unstable complete heart block requiring temporary venous pacemaker support. Despite the absence of traditional risk factors or significant valvular disease on transthoracic echocardiogram, she was found to be persistently bacteraemic and subsequent transoesophageal echocardiogram identified large vegetation on the septal leaflet of the TV. Conduction disease was noted to reverse with antibiotic therapy and resolution of bacteraemia. Discussion Although rare, right-sided endocarditis involving the triangle of Koch may present with conduction disease due to local inflammation and mechanical compression. Conduction disease associated with right-sided disease appears to be readily reversible with medical therapy and temporary device support may be appropriate in the acute setting.

Sutureless aortic valve with supracoronary ascending aortic replacement as an alternative strategy for composite graft replacement in elderly patients

Aortic valve disease is frequently associated with ascending aorta dilatation and can be treated either by separate replacement of the aortic valve and ascending aorta or by a composite valve graft. The type of surgery is depending on the exact location of the aortic dilatation and the concomitant valvular procedures required. The evidence for elective aortic surgery in elderly high-risk patients remains challenging and therefore alternative strategies could be warranted. We propose an alternative strategy for the treatment of ascending aortic aneurysm and aortic valve pathology with the use of a sutureless, collapsible, stent-mounted aortic valve prosthesis.