A parametric study regarding structural design of a bioprosthetic aortic valve by 3D fluid-structure interaction simulations.

Since the introduction of transcatheter aortic valve (AV) implantation as a viable option, surgical bioprosthetic AVs have recently started incorporating shorter struts considering future valve-in-valve procedures. However, the effect of leaflet coaptation geometry on the longevity of these valves remains unexplored. To address this gap, we performed a finite element analysis on bioprosthetic AVs with varying strut heights using a two-way fluid-structure interaction method. To establish a baseline, we used a standard height based on a rendered platform image of the CE PERIMOUNT Magna Ease valve from Edward Lifesciences in Irvine, CA. Bovine pericardium properties were assigned to the leaflets, while normal saline properties were used as the recirculating fluid in hemodynamic simulations. The physiological pressure profile of the cardiac cycle was applied between the aorta and left ventricle. We calculated blood flow velocity, effective orifice area (EOA), and mechanical stress on the leaflets. The results reveal that as the strut height increases, the stroke volume increases, leakage volume decreases, and EOA improves. Additionally, the maximum mechanical stress experienced by the leaflet decreases by 62% as the strut height increases to 1.2 times the standard height. This research highlights that a low-strut design in bioprosthetic AVs may negatively affect their durability, which can be useful in design of next-generation bioprosthetic AVs.

Long-term effects of left atrial appendage isolation in surgical ablation of atrial fibrillation based on lesion set: a multi-centre propensity-score weighted study.

BACKGROUND: This present study aimed to investigate the impact of left atrial appendage (LAA) isolation on adverse clinical outcomes, with a further stratified analysis by biatrial (BA) and left atrial lesion sets, in patients with atrial fibrillation (AF) undergoing surgical ablation (SA) concurrent with mitral valve (MV) surgery. METHODS: We evaluated 875 patients (aged 65.1±12.0 years) who underwent SA of AF concomitant to MV surgery, excluding those with mechanical prostheses requiring lifelong anticoagulation, between 2005 and 2017 in five tertiary cardiac centres in South Korea. Of these, 458 had isolated the LAA, whereas the remainder (n=417) had the LAA preserved. Comparative risk of stroke, mortality and AF recurrence was assessed between the groups, considering death as a competing event. Inverse-probability treatment weighting was used for baseline adjustment. RESULTS: During the median follow-up of 57.4 months (IQR, 32.5-92.4 months), the adjusted risk of long-term stroke was significantly lower in the patients who underwent LAA isolation compared with those who preserved the LAA (subdistribution HR (SHR), 0.28; 95% CI 0.15 to 0.51; p<0.001). However, there were no significant differences in the adjusted risk of mortality (HR, 0.85; 95% CI 0.57 to 1.27; p=0.429) or AF recurrence (SHR, 0.92; 95% CI 0.78 to 1.08; p=0.291) between LAA isolation and preservation. In the subgroup of patients who underwent BA ablation, LAA isolation was associated with a lower long-term risk of stroke and AF recurrence (SHR, 0.77; 95% CI 0.61 to 0.94; p=0.029) compared with LAA preservation. CONCLUSIONS: Concomitant LAA isolation during SA of AF in patients undergoing MV surgery was associated with a significantly lower risk of long-term stroke, but no survival benefit was observed.

The long-term impact of lesion set in the surgical ablation of atrial fibrillation during mitral valve surgery: multi-center propensity-score weighted study.

OBJECTIVE: This study aimed to assess the effect of the lesion sets for surgical ablation (SA) of atrial fibrillation (AF) on long-term outcomes and identify the optimal lesion set. METHODS: Between 2005 and 2017, 1825 patients underwent SA concomitant to mitral valve (MV) surgery in the participating institutions. Of these, 529 underwent left atrial (LA) ablation, whereas the remainder had biatrial (BA) ablation. The clinical and rhythm outcomes were compared, considering death as a competing event. Inverse probability treatment weighting (IPTW) was used to mitigate the selection bias. RESULTS: The patients undergoing LA ablation were younger and less frequently had long-standing AF with a shorter duration or required concomitant tricuspid valve surgery. Adjusted analysis showed that LA ablation was associated with a lower risk of early pacemaker implantation (odds ratio, 0.16; 95% confidence interval [CI], 0.07-0.38; p<0.001) than BA ablation. Over a median follow-up of 70.4 months (interquartile 44.1-111.2 months), the LA ablation group presented a higher risk of AF recurrence (subdistribution hazard ratio [SHR]1.26; 95% CI 1.12-1.41; p<0.001), with a 5-year cumulative incidence of 34.2% compared to 28.6% in the BA group. The risk of late mortality (SHR, 1.17; 95% CI, 0.74-1.86; p=0.507) and stroke (SHR, 1.21; 95% CI, 0.82-1.79; p=0.345) did not differ between the groups CONCLUSION: In patients undergoing SA concomitant to MV surgery, both lesion sets provided comparable incidence of mortality and stroke. However, BA ablation was associated with a superior rhythm outcome at the expense of a higher risk of early pacemaker implantation.

Effect of physical activity on risk reduction of infective endocarditis among patients with diabetes: a nationwide cohort study.

Patients with diabetes mellitus (DM) are at a higher risk of infectious diseases, and exercise is an important treatment modality for DM. Despite their susceptibility to infection in diabetic patients, the association between the amount of physical activity and the incidence of infective endocarditis (IE) is unclear. We attempted to demonstrate risk reduction by physical activity in diabetic patients with IE. From the National Health Insurance database, patients with DM were verified, and the incidence of IE was investigated. The level of physical activity was categorized into < 500, 500-999, 1,000-1,499, and ≥ 1,500 metabolic equivalent task (METs) minutes/week. Cox proportional hazard models were used to analyze the relationship between incident IE and physical activity. A total of 2,603,012 patients were included in this study. The incidence rate of IE was 10.06, 9.45, 7.78, and 8.84 in < 500, 500-999, 1,000-1,499, and ≥ 1,500 METs-minutes/week groups, respectively (100,000 person/year). A significant risk reduction of incident IE was observed in the 1,000-1499 and ≥ 1,500 METs-min/week groups compared to the < 500 METs-min/week group (Hazard ratio = 0.82, 95% confidence interval [0.690-0.976], HR = 0.831, 95% CI [0.704-0.981]). An analysis of a large national cohort database demonstrated that physical exercise reduced the risk of IE in patients with DM.

Impact of the Duration of Postoperative Antibiotics on the Prognosis of Patients with Infective Endocarditis.

Appropriate postoperative antibiotic treatment in patients with infective endocarditis (IE) reduces the risks of recurrence and mortality. However, concerns about adverse drug reactions arise due to prolonged antibiotic usage. Therefore, we compared the recurrence and mortality rates according to the duration of postoperative antibiotic therapy in patients with IE. From 2005 to 2017, we retrospectively reviewed 416 patients with IE treated at a tertiary hospital in South Korea; among these, 216 patients who underwent heart valve surgery and received appropriate antibiotics were enrolled. The patients were divided into two groups based on the duration of usage of postoperative antibiotic therapy; the duration of postoperative antibiotic therapy was more than two weeks in 156 patients (72.2%) and two weeks or less in 60 patients (27.8%). The primary endpoint was IE relapse. The secondary endpoints were 1-year IE recurrence, 1-year mortality, and postoperative complication rates. The median age was 53 (interquartile range: 38-62) years. The relapse rate of IE was 0.9% (2/216). There was no statistical difference in relapse (0.0% vs. 1.3%, p = 0.379), 1-year recurrence (1.7% vs. 1.3%, p = 0.829), or 1-year mortality (10.0% vs. 5.8%, p = 0.274) between patients with postoperative antibiotic administration of two weeks or less versus more than two weeks. The duration of postoperative antibiotic therapy did not affect the 1-year mortality rate (log-rank test, p = 0.393). In conclusion, there was no statistically significant difference in recurrence, mortality, or postoperative complications according to the duration of postoperative antibiotic therapy.

Does Surgical Ablation of Atrial Fibrillation Benefit Patients Undergoing Bioprosthetic Valve Replacement?

The benefit of avoiding lifelong anticoagulation therapy in patients with bioprosthetic heart valve implantation may potentially be offset by atrial fibrillation (AF); however, clinical impact of surgical AF ablation in such patients remains controversial. We enrolled 426 patients (aged 72.0 ± 7.8 years) with AF who underwent left-side valve replacement with bioprostheses between 2001 and 2018. Of these, 297 underwent concomitant surgical ablation (ablation group) and 129 underwent valve replacement alone (non-ablation group). Clinical outcomes were compared, and mortality was considered as a competing risk factor against valve-related complications. Inverse-probability weighting (IPTW) was adopted to reduce selection bias. The ablation group had lower baseline risk profiles than the non-ablation group. In crude analysis, early mortality rates were 3.4% and 7.0% in the ablation and non-ablation groups, respectively (P = 0.104). During follow-up (1521.9 patient-years), the ablation group showed lower AF-recurrence (P < 0.001) and anticoagulant medication rate (P = 0.021), and lower overall mortality risk (subdistribution hazard ratio [SHR], 0.63; 95% confidence interval [CI], 0.42-0.94), but higher risk of permanent pacemaker implantation (SHR, 4.67; 95% CI, 1.36-16.05). No significant difference in the risk of stroke (SHR, 1.27; 95% CI, 0.55-2.95) was observed between the groups. After baseline IPTW-adjustment, findings of the clinical outcomes were analogous to those from crude analyses. In patients undergoing bioprosthetic valve replacement, the addition of surgical ablation was associated with improved rhythm outcomes and survival but at the expense of a higher risk of pacemaker implantation. The underlying mechanism of improved survival by AF ablation needs further investigation.

Sarcoma Resection With Complete Removal of Left Atrial Posterior Wall.

We report a case of recurrent left atrial (LA) intimal sarcoma invading pulmonary veins (PVs) that was treated by a novel surgical approach-resecting LA wall and PVs down to segmental levels, and then creating neo-LA using lung hilum and posterior mediastinal soft tissue without further reconstructive procedures. This surgical approach may be useful in selected cases with primary cardiac malignancy involving LA and PVs in the aim of achieving complete resection of the tumor.

Mini-access open arch repair.

BACKGROUND: The use of minimally invasive approaches is scarce in open aortic arch repair because of its perceived high operative risk and technical difficulty. METHODS: This study enrolled 59 consecutive patients (aged 58.2±13.2 years) undergoing elective arch replacement either through upper hemi-sternotomy (n=58) or mini-thoracotomy (n=1) between 2015 and 2020. Of these, 44 underwent hemiarch replacement and 15 underwent total arch replacement. Moderate hypothermic circulatory arrest was used for all patients while antegrade cerebral perfusion was selectively used for total arch repair. For more efficient distal aortic anastomosis in limited spaces, inverted graft anastomosis was utilized whenever possible. RESULTS: Hemi-sternotomy involved upper sternal separation down to the second, third, and fourth intercostal spaces in 1 (1.7%), 30 (50.8%), and 27 (45.8%) patients, respectively. Concomitant cardiac procedures included root replacement in 19 patients (32.2%) and aortic valve replacement in 21 patients (35.6%). Circulatory arrest, cardiac ischemic, cardiopulmonary bypass, and total procedural times were 8.9±3.4, 91.1±31.1, 114.6±46.2, and 250.3±79.5 min, respectively for total arch repair, and 25.0±12.1, 72.3±16.6, 106.0±16.9, and 249.1±41.7 min, respectively for hemiarch repair. Conversion to full-sternotomy was required in 1 patient (1.7%) due to bleeding. There was one case of mortality (1.7%) attributable to low-cardiac output syndrome following hemiarch repair concomitantly with Bentall procedure. Major complications included requirement for mechanical support in 1 (1.7%), temporary neurologic deficit in 1 (1.7%), newly initiated dialysis in 3 (5.1%), and re-exploration due to bleeding in 2 (3.4%). CONCLUSIONS: Mini-access open arch repair is technically feasible and achieved excellent early outcomes.

Comparative Surgical Outcomes of Prosthetic and Native Valve Endocarditis.

BACKGROUND AND OBJECTIVES: As a consequence of a growing number of patients undergoing prosthetic heart valve replacement, the incidence of prosthetic valve endocarditis (PVE) has increased. The study aims to analyze patterns and outcomes of PVE surgery as compared with native valve endocarditis (NVE). METHODS: We enrolled 269 patients (aged 58.0±15.7 years) who underwent valve surgery for infective endocarditis (IE) between 2013 and 2019. Of these, 56 had PVE whereas remainder (n=213) had NVE. Clinical outcomes were compared and multivariable analyses were conducted to determine risk factors for mortality. RESULTS: The proportion of PVE among surgical IE gradually increased from 15.4% (11/71) in the first time-quartile to 29.5% (18/61) in the last time-quartile (p=0.055). PVE patients were older, and more commonly had aorto-mitral curtain involvement and abscess formation than NVE group. Early mortality was 14.3% and 6.1% in PVE and NVE group, respectively (p=0.049). Postoperatively, PVE group had higher incidences of low cardiac output syndrome (p=0.027), new-onset dialysis (p=0.006) and reoperation for bleeding (p=0.004) compared to NVE group, but stroke rates were comparable (p=0.503). During follow-up (648.8 patient-years), PVE group showed significantly higher risks of overall mortality (p<0.001), valve reinfection (p<0.001) and permanent pacemaker implantation (p<0.001) than NVE group. On multivariable analysis, PVE (hazard ratio, 2.67; 95% confidence interval, 1.40-5.07; p=0.003) along with age, chronic kidney disease, multi-valve involvement, and causative organisms of Staphylococcus aureus or fungus were independent risk factors of overall mortality. CONCLUSIONS: PVE carried significant perioperative risks, and was an independent risk factor of overall mortality.

Surgical Treatment for Left Main Coronary Atresia with Significant Mitral Regurgitation in a 1-Year-Old Child.

Congenital atresia of the left main coronary artery (LMCA) is an extremely rare coronary anomaly that necessitates surgical correction. Patients with LMCA atresia may have various clinical symptoms, which are determined by the degree of collateral vessel development from the right coronary system, the metabolic demands of the heart, and concomitant mitral insufficiency caused by myocardial ischemia. Unlike in adults, there are limited surgical options for coronary artery disease in children. Herein, we report a case of LMCA atresia with mitral regurgitation in a 19-month-old child that was successfully corrected by coronary artery bypass grafting and mitral valve repair.

Comparison of Sutureless Bioprosthetic Valve With Surgical or TAVR for Severe Aortic Stenosis.

Background: Clinical advantages of sutureless rapid-deployment (RD) aortic valve replacement (AVR) for severe aortic valve stenosis (AS) have not been elucidated compared with surgical (SAVR) or transcatheter (TAVR) aortic valve replacement. Objectives: This study sought to investigate comparative effectiveness and safety of RD-AVR compared with SAVR and TAVR in a prospective cohort of patients with severe AS. Methods: The primary outcome was a composite of death, stroke, or rehospitalization at 12 months. Propensity score matching was used to assemble a cohort of patients with similar baseline characteristics. Results: Among 1,020 eligible patients, 107 (10.5%) underwent RD-AVR, 437 (42.8%) underwent SAVR, and 476 (46.7%) underwent TAVR. In the matched cohorts of RD-AVR and SAVR (n = 107), the incidence of primary composite outcome at 12 months was similar between the 2 groups (8.0% vs 10.8%, respectively; hazard ratio [HR]: 0.74; 95% confidence interval [CI]: 0.30-1.84; P = 0.52). In the matched cohorts of RD and TAVR (n = 58), the incidence of primary composite outcome at 12 months did not statistically differ between the 2 groups (9.4% vs 16.2%, respectively; HR: 0.53; 95% CI: 0.18-1.57; P = 0.25). Conclusions: In this propensity-matched cohort of patients who underwent AVR for severe AS, we did not detect significant differences in the rates of the primary composite of death, stroke, or rehospitalization at 12 months when comparing RD-AVR with SAVR and TAVR. Because the study was underpowered, the results should be considered as hypothesis generating highlighting the need for further research. (ASAN Medical Center Aortic Valve Replacement Registry [ASAN-AVR]; NCT03298178).

A Huge Pericardial Gossypiboma Causing Severe Cardiac Dysfunction.

Gossypiboma-a surgical cotton matrix inadvertently left in the body cavity-is a rare postoperative complication, especially after cardiac surgery. We report a patient who presented with severe cardiac dysfunction caused by a huge pericardial gossypiboma that was detected 30 years after the previous cardiac surgery. This case delineates the serious medical consequences caused by pericardial gossypiboma and suggests considering gossypiboma as a differential diagnosis of a pericardial mass in patients with a history of cardiac surgery.

Recurrent Mediastinal Sarcoma in the Aortic Arch.

As mediastinal sarcomas commonly present as large tumors invading adjacent vital structures, complete resection is frequently challenging. For such tumors, aggressive surgical strategies, such as the resection and reconstruction of the invaded vital structures under cardiopulmonary bypass, may be required to achieve complete resection and to improve survival. Herein, we report a case of recurrent mediastinal sarcoma invading the aortic arch and arch vessels that was successfully removed by total arch replacement.