Mechanical Valve Research Articles

Decellularized aortic homografts versus mechanical composite grafts for aortic root replacement.

Mechanical composite valve grafts (MCVGs) are the first-line therapy for aortic root replacement in young adults. Decellularized aortic homografts (DAH) present a promising novel alternative due to their lower thrombogenicity. We aimed to compare both treatment options regarding survival and valve-related adverse events. This study was designed as a single-centre retrospective cohort study including patients who underwent root replacement with MCVG or DAH between 2000 and 2022. Urgent or emergent procedures were excluded. The study cohort included 289 patients (MCVG n = 216, DAH n = 73) with a mean age of 48.5 ± 12 years (MCVG 49 ± 12 years vs DAH 47 ± 11 years; P = 0.23) and a median EuroScore II of 1.7% (1.2, 2.6). The 30-day mortality was 1% (n = 3). Cumulative survival at 3 years was 99% for DAH and 94% for MCVG, respectively (P = 0.15). Mean follow-up was 98.9 ± 72.7 months. Bleeding events (n = 14, 6.5%) and thromboembolism (n = 14, 6.5%) were only observed in the MCVG group (P = 0.19 and 0.09, respectively). Four cases (5%) of moderate structural valve deterioration occurred, all in the DAH group (P ≤ 0.001). The cumulative incidence of a composite end point of valve-related adverse events was significantly higher in the MCVG group (P = 0.0295). Aortic root replacement with MCVGs and decellularized aortic homografts showed low mortality in an elective setting. Patients in the homograft cohort demonstrated significantly higher freedom from valve-related adverse events. DAH present a promising treatment option for young patients requiring root replacement; however, data on long-term durability are needed.

Comparison of vortex formation in expanded and curved aortic sinuses: The effect of sinus curvature

Aortic valve disease is a significant health issue. Research on the effects of aortic sinus geometry and aortic valve motion during a heartbeat is imperative, as numerous valvular diseases are associated with blood flow near the heart valve. Changes in the internal space of the sinus and the formation of blood clots have been reported after the implantation of a transcatheter aortic valve, an artificial heart valve. Although the sinus shape and leaflet motion significantly affect the hemodynamic characteristics and platelet aggregation, the blood flow behaviors near the heart valve associated with clot formation have not been fully elucidated. This study conducted in vitro experiments to investigate the flow behavior near an aortic sinus model based on the sinus shape. Additionally, hemodynamic changes associated with variations in the aortic sinus geometry and leaflet length within an aortic sinus model under pulsatile-flow conditions were elucidated. In a curved sinus model, a large single vortex formed near the center of the sinus region. Meanwhile, the center of the vortex in the sinus region shifted during a cycle in an expanded sinus model. Furthermore, a small vortex remained where the leaflet was initiated, thus increasing the likelihood of thrombus formation. Thus, the curved sinus model is advantageous for preventing material accumulation by maintaining a large vortex structure. The experimental results confirmed that the aortic sinus shape and leaflet length affect the likelihood of thrombus formation inside the aortic sinus.

Cardiac surgery and acute hepatitis B - Use of the Seraph™ 100 hemofilter.

We present a case of a 55-year-old male, presenting with angina symptoms with electrocardiographic changes and a panfocal systolic murmur radiating to the carotids. He had a primary HBV infection 8 months ago, without antiviral treatment. Echocardiography showed critical aortic valve stenosis (area: 0.53 cm2/m2). No coronary lesions were found on coronary angiography. Blood analysis revealed AST/GOT of 96 U/L and ALT/GPT 150 U/L. The serological profile revealed positive IgM anti-HBc, anti-HBc, anti-HBs and anti-HBe antibodies, with an increasing viral load (VL). The abdominal ultrasound identified mild hepatic fibrosis (F3) with minimal steatosis. Mechanical aortic prosthetic valve replacement was performed under CPB. The Seraph™ 100 filter was incorporated into the CPB circuit to reduce the risk of HBV contamination, infection and liver failure. The postoperative VL was monitored (Table 1). Liver function tests showed peak levels of bilirubin 0.66 mg/dL, AST/GOT 58 U/L, ALT/GPT 74 U/L at 6 hours post-surgery, with recovery of normal ranges at 48 hours post-surgery.

Is Cardiac Surgery Safe During Pregnancy? A 40-Year Single-Institution Experience

BackgroundLimited data exist to characterize maternal and fetal outcomes during pregnancy undergoing cardiac operations using cardiopulmonary bypass. MethodsA retrospective review was performed of all pregnant individuals who underwent cardiac surgery using cardiopulmonary bypass at a single center from 1978 to 2023. Descriptive statistical analysis was performed, with a median reported for continuous variables and incidence for dichotomous variables. ResultsTwenty-nine pregnant patients with a median age of 28 years (interquartile range [IQR], 25-32 years) years underwent cardiac surgery using cardiopulmonary bypass at a median gestation of 25 weeks (IQR, 16-29 weeks). Surgery was performed in the first trimester for 3 patients (10%), second trimester for 16 (55%), and third trimester for 10 (35%). Procedures were emergent in 15 (52%) and urgent in 14 (48%). There was 1 (3%) maternal death 2 days after mechanical aortic valve thrombectomy and 5 (17%) fetal losses. Fourteen patients who underwent cardiac surgery using cardiopulmonary bypass with continuing pregnancy experienced a 29% fetal mortality rate, and 7 patients underwent delivery before surgery and experienced 14% fetal mortality. Among cases of fetal loss, surgery was performed at a median of 25 weeks (IQR, 21-26 weeks) compared with a median of 23 weeks (IQR, 20-29 weeks) in cases without fetal loss (P = .55). ConclusionsCardiac surgery during pregnancy was associated with low maternal mortality but significant fetal mortality. This single-institution series supports consideration of cesarean delivery before cardiopulmonary bypass procedures if the fetus is of a viable gestational age to minimize mortality.

Ascending Aorta Anastomotic Aneurysm Exclusion with Double-Fenestrated PMEG after Open Repair

The objective of this case series is to investigate the outcomes of double-fenestrated physician-modified endografts (PMEGs) in patients with distal anastomotic aneurysms after open repair of the ascending aorta or proximal arch replacement. All consecutive patients with a distal anastomotic aneurysm after open ascending aorta surgery who underwent aortic arch repair with a homemade double-fenestrated stent-graft from 2017 to 2023 were reviewed. Study endpoints included technical success, 30-day, and long-term follow up analysis of mortality, morbidity, and reinterventions. 10 patients were treated with double-fenestrated PMEGs for anastomotic aneurysms after open surgery of the ascending aorta. Of these, 9 were male with a mean age of 58years. Nine patients were initially treated for acute dissection, and 2 had mechanical aortic valves. The mean time between open surgery and the treatment of the pseudoaneurysm was 4.15years. Technical success was 100%. The proximal landing zone was consistently in zone 0, and all endografts were deployed via femoral access. Early outcomes revealed one endoleak (type 1a), which was successfully treated by prompt reintervention. No deaths or strokes occurred during the early postoperative period. During long-term follow up (mean time 35months), no endoleaks requiring intervention occurred, and there were no reports of stent fractures or migrations. No patient died from an aortic-related cause. Aortic arch repair with double-fenestrated PMEGs for distal anastomotic aneurysms after open surgery is feasible and represents a promising alternative in patients ineligible for redo surgery.

An Implantable Magnetic Drive Mechanism for Non-Invasive Arteriovenous Conduit Blood Flow Control.

Hemodialysis patients usually receive an arteriovenous fistula (AVF) in the arm as vascular access conduit to allow dialysis 2-3 times a week. This AVF introduces the high flow necessary for dialysis, but over time the ever-present supraphysiological flow is the leading cause of complications. This study aims to develop an implantable device able to non-invasively remove the high flow outside dialysis sessions. The developed prototype features a magnetic ring allowing external coupling and torque transmission to non-invasively control an AVF valve. Mock-up devices were implanted into arm and sheep cadavers to test sizes and locations. The transmission torque, output force, and valve closure are measured for different representative skin thicknesses. The prototype was placed successfully into arm and sheep cadavers. In the prototype, a maximum output force of 78.9 ± 4.2 N, 46.7 ± 1.9 N, 25.6 ± 0.7 N, 13.5 ± 0.6 N and 6.3 ± 0.4 N could be achieved non-invasively through skin thicknesses of 1-5 mm respectively. The fistula was fully collapsible in every measurement through skin thickness up to the required 4 mm. The prototype satisfies the design requirements. It is fully implantable and allows closure and control of an AVF through non-invasive torque transmission. In vivo studies are pivotal in assessing functionality and understanding systemic effects. A method is introduced to transfer large amounts of energy to a medical implant for actuation of a mechanical valve trough a closed surface. This system allows non-invasive control of an AVF to reduce complications related to the permanent high flow in conventional AVFs.

Delayed iatrogenic atrial septal defect after implantation of a bicaval prosthesis device for the treatment of tricuspid regurgitation.

We present the case of a 71-year-old woman with rheumatic valvular disease who underwent mitro-aortic mechanical valve replacement and tricuspid annuloplasty in 2011. She required a dual-chamber pacemaker in 2012 and developed severe tricuspid regurgitation (TR), leading to percutaneous annuloplasty with Cardioband® system in 2021.

Transcatheter closure management of mitral paravalvular leakage: A single center experience.

Paravalvular leakage (PVL) is a common complication after artificial valve replacement. Transcatheter paravalvular leak closure (PVT), an efficient, safe, and minimally invasive treatment for PVL patients. The purpose of this study was to present our experience with transcatheter closure of mitral paravalvular leakage (PVL) after surgical valve replacement in our center. A cohort of 81 consecutive patients with mitral PVLs was treated with transcatheter closure between September 2014 and December 2022. We reviewed the demographics, clinical features, therapeutic modalities and follow-up results. The patients' charts were used for retrospective analysis. Eighty-one patients from one center were enrolled in this study. The median age of the patients was 63 ± 11 years. The median LVEF was 51% ± 7%, and the median regurgitation volume was 11.5 ± 10.1 mL. Sealing with occlusion was successful in 70 patients, and the technical success rate was 86.5%. The median regurgitation volume was reduced to 1.95 ± 2.6 mL. The major adverse event was hemolysis, which affected 19 patients, 17 of whom required blood transfusion. Three patients required secondary open surgery due to bleeding. Three patients died during the hospital stay, and all of their deaths were caused by hemolysis-related complications. The median hospital stay was 10.3 ± 6.3 days. During the follow-up period, 2 patients died, and none of their deaths were caused by surgery. The New York Heart Association classification increased in all patients during the 6-month follow-up. Transcatheter mitral PVL closure requires complex catheter techniques. However, this technique is minimally invasive and has a shorter hospital stay. Interventional mitral PVL closure is a safe and efficacious technique for high-risk surgical patients with symptomatic paravalvular regurgitation.

Rivaroxaban versus vitamin K antagonist treatment on the progression of coronary calcification: the IRIVASC-trial

Vitamin K antagonists (VKA) remain the only option of anticoagulation for people with mechanical valve replacement and due to their wider availability and lower acquisition costs, VKA’s remain widely used in low- and middle-income countries. It has been suggested that prolonged use of VKAs can increase the development of vascular and valvular calcification, though this effect has not been examined in larger randomized prospective trials. This investigator-initiated multicenter, prospective, randomized, open-label interventional trial randomized patients with baseline coronary or valvular calcification and an indication for prolonged oral anticoagulation therapy to Marcumar or Rivaroxaban. Patients were followed-up through repeat coronary computed tomographies to measure the progression of coronary and valvular calcification for up to 24 months. 192 patients were randomized between 2013 and 2018 to receive either Rivaroxaban or Marcumar and followed for up to 24 months. Coronary calcification significantly increased over time although there was no significant difference in progression between the groups after 12 and 24 months as measured by the Agatston score [360.7 (90.2; 1075.3) vs 380.4 (136.4; 1546.9) p = 0.69], the volume score [295.8 (93.0; 995.3) vs 335.5 (128.7; 1316.9) p = 0.95] and the mass score [58.5 (15.9; 172.0) vs 71.1 (24.8; 257.3) p = 0.5]. Dephosphorylated, uncarboxylated matrix Gla Protein (Dp-ucMGP) significantly decreased in the VKA group [Δ dp-uc MGP – 95.2 (− 554.1; 156.0) vs 231.3 (− 59.7; 388.1) p < 0.001]. There does not appear to be a relevant effect of vitamin K inhibition by the vitamin K antagonist marcumar upon coronary calcification.

Outcome of Corynebacterial Bloodstream Infection in Patients With Cardiac Implantable Electronic Devices: A Brief Report and Systematic Review.

Cardiac implantable electronic device infection in the context of corynebacterial bloodstream infection (BSI) remains poorly understood. From 2012 to 2023 at Mayo Clinic, 4 of 12 patients with corynebacterial BSI had cardiac implantable electronic device infection: 1 patient was diagnosed during a relapsing BSI episode. Undefined source, persistent BSI, and the presence of a prosthetic cardiac valve were common characteristics.

Construction of cirRNA-miRNA-mRNA network and MAPK1 protein signaling pathway in patients with valvular disease affected by artificial heart valve replacement surgery

The progress of modern medical technology has made artificial heart valve replacement an effective means to treat valvular disease, but the impact of cardiac function on patients after surgery is still a key issue. The purpose of this study was to construct the cirRNA-miRNA-mRNA network after artificial heart valve replacement in valvular disease patients, and to explore the regulatory mechanism related to MAPK1 protein, so as to reveal its potential role in affecting cardiac function. We downloaded cyclic cRNA expression profiles from the GEO database. Use the limma package to identify dec. WGCNA is used to identify key modules of circular rna. The target miRNAs of circular rna and the corresponding target genes of miRNAs were screened by ring intertome and target scan database. GO and KEGG analysis using the DAVID database. The genes associated with iron sag disease were derived from FerrDb database. The overlapping genes were obtained by Wien analysis. Next, the CircrNa-mirNa-mrna network was constructed based on the circRNA-miRNA pair and miRNA-mRNA pair and their cyclic landscape software. This study revealed the changes in the structure and expression of MAPK1 protein in the cirRNA-miRNA-mRNA network after artificial heart valve replacement in valvular disease patients, suggesting the potential role of MAPK1 protein in regulating cardiac function, and laying a foundation for further revealing its mechanism and clinical application.

Efficacy and Safety of Warfarin Utilisation in Rheumatic Heart Disease Patients With Mechanical Heart Valves in Remote Northwest Queensland

Efficacy and Safety of Warfarin Utilisation in Rheumatic Heart Disease Patients With Mechanical Heart Valves in Remote Northwest Queensland

Role of 3D transoesophageal echocardiography in the study of infective endocarditis. Demonstration in a case collection.

Infective endocarditis (IE) is a condition that predominantly affects native or prosthetic heart valves, which is currently on the rise due to the increase in invasive cardiology procedures, such as the utilization of cardiac implantable electronic devices and transcatheter interventions. The recommended imaging tests for diagnosis are 2D transthoracic echocardiography (2D TTE) and 2D transoesophageal echocardiography (2D TOE). However, these modalities present limitations in detecting vegetations and estimating their dimensions. These disadvantages can be overcome by 3D transoesophageal echocardiography (3D TOE), particularly with the multiplanar reconstruction tool, which allows for the visualization of infinite valve planes, thus optimizing the detection of lesions and precise measurements. Furthermore, the volume rendering provides insight into the anatomical relationships between lesions, which is particularly useful for surgical planning. In this review, we aim to discuss the role of this recent imaging modality in the diagnosis, prognosis, and therapeutic of IE. Finally, we present a collection of images that illustrate the use of 3D TOE tools.

Transcatheter Aortic Valve Implantation in Rheumatic Aortic Valve Stenosis Using a Top-down Deployment Supra-annular Leaflets Transcatheter Aortic Valve: Technical Considerations

Aortic valve stenosis due to chronic rheumatic heart disease remains prevalent in the Asia-Pacific region. Because of the lack of substantial calcification that can anchor a transcatheter aortic valve, there are several technical considerations during transcatheter aortic valve implantation (TAVI) when treating this subset of patients. We report a case of successful TAVI using a novel top-down deployment supra-annular leaflets valve in a patient with rheumatic aortic valve stenosis and mechanical mitral valve prosthesis.

Age-Specific Outcomes of Bioprosthetic vs. Mechanical Aortic Valve Replacement: Balancing Reoperation Risk with Anticoagulation Burden.

The choice of prosthesis for aortic valve replacement (AVR) remains challenging. The risk of anticoagulation complications vs. the risk of aortic valve reintervention should be weighed. This study compared the outcomes of bioprosthetic vs. mechanical AVR in patients older and younger than 50. This retrospective study was conducted from 2009 to 2019 and involved 292 adult patients who underwent isolated AVR. The patients were divided according to their age (above 50 years or 50 years and younger) and the type of valves used in each age group. The outcomes of bioprosthetic valves (Groups 1a (>50 years) and 1b (≤50 years)) were compared with those of mechanical valves (Groups 2a (>50 years) and 2b (≤50 years)) in each age group. The groups had nearly equal rates of preexisting comorbidities except for Group 1b, in which the rate of hypertension was greater (32.6% vs. 14.7%; p = 0.025). This group also had higher rates of old stroke (8.7% vs. 0%, p = 0.011) and higher creatinine clearance (127.62 (108.82-150.23) vs. 110.02 (84.87-144.49) mL/min; p = 0.026) than Group 1b. Patients in Group 1a were significantly older than Group 2a (64 (58-71) vs. 58 (54-67) years; p = 0.002). There was no significant difference in the NYHA class between the groups. The preoperative ejection fraction and other echocardiographic parameters did not differ significantly between the groups. Re-exploration for bleeding was more common in patients older than 50 years who underwent mechanical valve replacement (p = 0.021). There was no difference in other postoperative complications between the groups. The groups had no differences in survival, stroke, or bleeding rates. Aortic valve reintervention was significantly greater in patients ≤ 50 years old with bioprosthetic valves. There were no differences between groups in the changes in left ventricular mass, ejection fraction, or peak aortic valve pressure during the 5-year follow-up. The outcomes of mechanical and bioprosthetic valve replacement were comparable in patients older than 50 years. Using bioprosthetic valves in patients younger than 50 years was associated with a greater rate of valve reintervention, with no beneficial effect on the risk of bleeding or stroke.

Epidemiological and microbial trends of infective endocarditis in western Norway: a 7-year prospective observational study

BackgroundIn this prospective, observational study, we aimed to investigate epidemiologic and microbial trends of infective endocarditis in western Norway.MethodsClinical and microbiological characteristics of 497 cases of infective endocarditis from 2016 through 2022 were investigated. Categorical data were analysed using Chi-squared tests. Survival data were analysed using multiple Cox regression and reported using hazard ratios.ResultsThe mean age was 67 years, and 74% were men. The annual incidence rates varied from 10.4 to 14.1 per 100,000 inhabitants per year. Infective endocarditis on native valves was observed in 257 (52%) of the cases, whereas infective endocarditis on prosthetic valves and/or cardiac implantable electronic devices was observed in 240 (48%) of the cases: infection on surgically implanted bioprostheses was observed in 124 (25%) of the patients, infection on transcatheter aortic valve implantation was observed in 47 (10%) patients, and infection on mechanical valves was observed in 34 (7%) cases. Infection related to cardiac implantable electronic devices was observed in a total of 50 (10%) cases.Staphylococcus aureus and viridans streptococci were the most common microbial causes, and isolated in 145 (29%) and 130 (26%) of the cases, respectively.Enterococcal endocarditis showed a rising trend during the study period and constituted 90 (18%) of our total cases of infective endocarditis, and 67%, 47%, and 26% of the cases associated with prosthetic material, transcatheter aortic valve implantation and cardiac implantable electronic devices, respectively.There was no significant difference in 90-day mortality rates between the native valve endocarditis group (12%) and the group with infective endocarditis on prosthetic valves or cardiac implants (14%), p = 0.522. In a model with gender, age, people who inject drugs, microbiology and type of valve affected, only advanced age was significantly associated with fatal outcome within 90 days.ConclusionsThe incidence of infective endocarditis, and particularly enterococcal endocarditis, increased during the study period. Enterococci appeared to have a particular affinity for prosthetic cardiac material. Advanced age was the only independent risk factor for death within 90 days.

Mechanical mitral valve obstruction: gone with the wind.

Mechanical mitral valve obstruction: gone with the wind.

Post-catheterization Common Femoral Artery Pseudoaneurysm in a Patient with a Mechanical Mitral Valve Requiring Anticoagulation: A Case Report

Iatrogenic femoral pseudoaneurysms are a rare complication of transfemoral vascular access. We present a case of a 65-year-old woman with a mechanical mitral valve requiring warfarin, who developed a femoral pseudoaneurysm four days after cardiac catheterization with femoral access. The patient developed a 17 x 10 x 17 cm rectus sheath hematoma and was treated with ultrasound-guided thrombin injection. Anticoagulation was held for three days while the patient was monitored for further bleeding and later restarted based on shared decision-making, given the risk of valve thrombosis. There are few guidelines regarding the re-initiation of anticoagulation in high-risk bleeding patients with mechanical mitral valves. Non-invasive coronary computed tomography angiography should be considered in patients on anticoagulation who require non-emergent cardiac ischemic evaluation.

A case of truncus arteriosus with severe heart failure and pulmonary stenosis: bridge to transplant candidacy with surgical correction and a ventricular-assist device.

Ventricular-assist device therapy for small patients with congenital heart disease is challenging due to its complex anatomy and hemodynamics. We describe a 3-year-old patient with heart failure with truncus arteriosus in the palliative stage. The patient underwent palliative right ventricular outflow tract reconstruction following bilateral pulmonary artery banding. At 6months of age, the patient developed severe truncal valve regurgitation and left ventricular dysfunction. Emergent truncal valve replacement with a mechanical valve was performed, but left ventricular dysfunction persisted. At 3years of age, the patient developed acute progression of heart failure triggered by influenza infection. The patient was intubated and transferred to our center to determine the indication for heart transplantation. On the second day after admission, signs of multiorgan failure appeared. Emergent ventricular-assist device implantation for both ventricles was performed with truncal valve closure, ventricular septal defect closure, atrial septal defect closure, and re-right ventricular outflow tract reconstruction. The right ventricular-assist device was successfully removed on the seventh postoperative day. Due to the small pulmonary arteries, severe pulmonary stenosis persisted after ventricular-assist device implantation, but it gradually improved with multiple pulmonary angioplasties. The patient was registered in the Japanese organ transplant network and is awaiting a donor organ in a stable condition.

Long-Term Results of Percutaneous Balloon Aortic Valvuloplasty in Children With Aortic Stenosis: A Single-Center Experience.

Congenital aortic stenosis is a common pathology in the childhood age group and its clinical spectrum varies between asymptomatic and severe heart failure. In our study, we planned to evaluate the long-term results of patients who underwent balloon aortic valvuloplasty (BAV) due to critical aortic valve stenosis in our clinic. Patients aged 0-18 years who underwent aortic balloon valvuloplasty due to aortic stenosis in our clinic between January 2002 and January 2022 were retrospectively evaluated. Among the 48 patients who underwent balloon valvuloplasty due to aortic stenosis, 13 (27%) were female, and 35 (73%) were male. The median age at the time of the procedure was 27.5 months (IQR: 4-96), the median weight was 9.9 kg (IQR: 5.40-29.50), and the median height was 79 cm (IQR: 54-133). The median follow-up duration was 93.5 months (IQR: 38-132). Angiographic assessments in all patients revealed a median left ventricular pressure of 160 mmHg (IQR: 140-200) and a median pressure gradient between the left ventricle and the aorta of 60 mmHg (IQR: 42-80). The median balloon diameter used was 10 mm (IQR: 8-12). Post-procedural measurements showed a median mean gradient of 30 mmHg (IQR: 20-35) between the left ventricle and the aorta. The procedure was successful in 45 (93.5%) patients. During follow-up, 11 patients required surgical intervention. Ross procedure was performed in five patients, homograft in five patients, and mechanical valve implantation in one patient. Risk factors for the need for surgical intervention were evaluated in detail. During the follow-up, the risk factor for intervention was determined to be aortic insufficiency. Aortic valve balloon valvuloplasty is a safe and successful treatment method for critical aortic stenosis. It should be the first choice of treatment option in suitable patients.