Hemodynamic Comparison of the On-X and Top Hat Mechanical Aortic Valve Prostheses.

BACKGROUND: There are limited data comparing hemodynamic valve function in mechanical aortic valve prostheses. We compared the hemodynamic function of two commonly used mechanical aortic valve (AV) prostheses, the On-X and Top Hat valves. METHODS: Retrospective analysis of 512 patients who received AV replacement with On-X (n=252, 49%) or Top Hat (n=260, 51%) mechanical valves between 2011 and 2019. Patients were matched based on select variables. Echocardiographic data were collected pre- and postoperatively over a median follow-up of 1.39 years. RESULTS: A total of 320 patients were matched, 160 patients in each group. Despite being matched for left ventricular outflow tract diameter, patients in the Top Hat group received a greater prevalence of smaller tissue annulus diameter valves (≤ 21 mm) (83% versus 38%; P<0.001). Patients in the On-X group had longer aortic cross-clamp time (78 versus 64 minutes; P<0.001) during isolated aortic valve replacement. Discharge echocardiography showed no difference in the AV area index between both groups (1.00 versus 1.02 cm2/m2; P=0.377). During longer-term echocardiographic follow-up, AV area index remained stable for both valves within their respective tissue annulus diameter groups (P=0.060). CONCLUSIONS: There was no difference between the two valves with respect to the AV area index at discharge, and hemodynamic function was stable during longer-term follow-up. The longer aortic cross-clamp time observed in the On-X group may indicate increased complexity in implantation compared to the Top Hat group.

Single Center Prospective Study of Cross-Clamp versus Balloon Occlusion in Robotic Mitral Surgery.

BACKGROUND: Both transthoracic aortic cross-clamp and endoaortic balloon occlusion have been shown to have comparable safety profiles for aortic occlusion. Since most surgeons use only one technique, we sought to compare the outcomes when a homogeneous group of surgeons changed their occlusion technique from aortic cross-clamp to balloon occlusion. METHODS: We changed our technique from aortic cross-clamp to balloon occlusion in November 2022. This allowed us to conduct a prospective treatment comparison study in the same group of surgeons. Propensity score matching (PSM) was used to match cases(balloon occlusion) 1:3 to controls (aortic cross-clamp) based on age, gender, body mass index, concomitant maze, and tricuspid valve repair. RESULTS: Total of 411 patients underwent robotic mitral surgery from 2020 through 2023. Using PSM, 56 balloon occlusion patients were matched to 168 aortic cross-clamp patients. Median age was 65 years (interquartile range[IQR],55.6-70.0) and the majority were males(n=119,53%). All valves were successfully repaired. Balloon occlusion had a shorter median cardiopulmonary bypass (CPB) time compared to aortic cross-clamp (84.0 vs. 94.5 min,p=0.006). Median cross-clamp time (64.0 vs. 64.0 min,p=0.483) and total surgery time (5.9 vs. 6.1 hours,p=0.495) did not differ between groups. There was no in hospital death. There were five surgeons who performed various combinations of console and bedside roles. CPB, cross-clamp, and surgery durations were not significantly affected by the different surgeon combinations. CONCLUSIONS: Compared to aortic cross-clamp, balloon occlusion has similar perioperative and early postoperative outcomes. Additionally, it likely introduces a 10-minute reduction in total CPB time.

Obstruction in Hypertrophic Cardiomyopathy: Many Faces.

Hypertrophic cardiomyopathy (HCM), the most common inherited cardiomyopathy, exhibits left ventricular hypertrophy not secondary to other causes, with varied phenotypic expression. Enhanced actin-myosin interaction underlies excessive myocardial contraction, frequently resulting in dynamic obstruction within the left ventricle. Left ventricular outflow tract obstruction, occurring at rest or with provocation in 75% of HCM patients, portends adverse prognosis, contributes to symptoms, and is frequently a therapeutic target. Transthoracic echocardiography plays a crucial role in the screening, initial diagnosis, management, and risk stratification of HCM. Herein, we explore echocardiographic evaluation of HCM, emphasizing Doppler assessment for obstruction. Echocardiography informs management strategies through noninvasive hemodynamic assessment, which is frequently obtained with various provocative maneuvers. Recognition of obstructive HCM phenotypes and associated anatomical abnormalities guides therapeutic decision-making. Doppler echocardiography allows monitoring of therapeutic responses, whether it be medical therapies (including cardiac myosin inhibitor therapy) or septal reduction therapies, including surgical myectomy and alcohol septal ablation. This article discusses the hemodynamics of obstruction and practical application of Doppler assessment in HCM. In addition, it provides a visual atlas of obstruction in HCM, including high-quality figures and complementary videos that illustrate the many facets of dynamic obstruction.

Outcomes of aortic surgery in patients with Takayasu arteritis.

OBJECTIVE: To investigate the presentation, aortic involvement, and surgical outcomes in patients with Takayasu arteritis undergoing aortic surgery. METHODS: We queried our surgical database for patients with Takayasu arteritis who underwent aortic surgery from 1994 to 2022. RESULTS: There were a total of 31 patients with Takayasu arteritis who underwent aortic surgery. Patients' median age at the time of diagnosis was 35.0 years (interquartile range, 25.0-42.0). The majority were female (n = 27, 87.0%). Most patients (n = 28, 90.3%) were diagnosed before surgery, and 3 patients (9.6%) were diagnosed perioperatively. The median time interval from diagnosis to surgery was 2.8 years (interquartile range, 0.5-13.9). The most common presentation was ascending aorta aneurysm (n = 22, 70.9%), and severe aortic regurgitation was the most common valve insufficiency (n = 17, 54.8%). The most common operation was ascending aorta replacement (n = 20, 64.5%), and aortic valve replacement was the most common valve intervention (n = 17, 54.8%). Active vasculitis was identified in 2 (11.7%) aortic valve specimens. Early mortality was 6.5% (n = 2). A total of 6 deaths occurred over a median follow-up of 13.1 years (interquartile range, 6.1-25.2). Survival at 10 years was 86.7% (95% CI, 75.4-99.7). A total of 5 patients (16.1%) required a subsequent operation in a median of 1.9 years (interquartile range, 0.2-7.4). Freedom from reoperation was 96.9% (95% CI, 90.1-100) at 1 year, 89.4% (95% CI, 78.7-100.0) at 5 years, and 77.5% (95% CI, 61.2-98.1) at 10 and 15 years. CONCLUSIONS: Ascending aorta aneurysm and aortic valve regurgitation are the most frequent presentations in patients with Takayasu arteritis requiring aortic surgery. Surgery in these individuals is safe, with acceptable short- and long-term results.

Treatment Strategies for Hypertrophic Cardiomyopathy: Surgical.

Septal myectomy is a well-established procedure for septal reduction in patients with obstructive hypertrophic cardiomyopathy (HCM) who have not responded to medical treatment. The surgical approach is tailored to the unique pathophysiology and septal morphology of the patient. Extended transaortic myectomy is the standard procedure for patients with isolated subaortic obstruction, the most common type of HCM. However, transapical myectomy is a useful adjunct for patients with long or midventricular obstruction and is our preferred technique for ventricular enlargement in patients with severe symptomatic diastolic heart failure because of extensive apical hypertrophy. Septal myectomy provides excellent postoperative outcomes as regards symptom relief and functional improvement, and operative morbidity and mortality rates are low in experienced centers. This article summarizes our current surgical management of patients with HCM and details operative methods and outcomes.

Post-mortem examination of fatal acute type A aortic dissection: what does it teach us?

OBJECTIVES: Acute type A aortic dissection (ATAAD) remains a highly life-threatening condition. This study investigates factors associated with fatal ATAAD prior to surgical treatment. METHODS: We reviewed autopsy reports of ATAAD decedents who died before surgical intervention and underwent postmortem examination at our clinic from 1994 to 2022. RESULTS: Among 94 eligible cases, 50 (53.2%) decedents had DeBakey type I dissection, and 44 (46.8%) had DeBakey type II dissection. Most were males, 63 (67%), and 72 (77%) had a history of hypertension. The median age was 70.5 years, and the type II group was a decade older than the type I group (P < 0.001). Decedents in the type II group predominantly died during the first hour after symptoms onset 16 (52%), while in the type I group, fatalities occurred between 1 h and 1 day, 27 (66%). The most common site of the intimal tear was the midportion of the ascending aorta, 45 (48%). The median ascending aorta size was 5 cm for the entire cohort, 5.2 cm for type I and 4.6 cm for type II (P < 0.045). CONCLUSIONS: In this autopsy study of fatal acute aortic dissection, the median aortic size was below the current guideline threshold for elective repair. Type II acute aortic dissections were found more frequently than expected and were characterized by older age, advanced aortic atherosclerosis, smaller aortic size, a shorter interval from symptom onset to death and a higher frequency of syncope compared to type I dissection.

Analysis of Anemia, Transfusions, and CABG Outcomes in The Society of Thoracic Surgeons National Database.

BACKGROUND: This study characterized the association of preoperative anemia and intraoperative red blood cell (RBC) transfusion on outcomes of elective coronary artery bypass grafting (CABG). METHODS: Data from 53,856 patients who underwent CABG included in The Society of Thoracic Surgeons (STS) Adult Cardiac Database in 2019 were used. The primary outcome was operative mortality. Secondary outcomes were postoperative complications. The association of anemia with outcomes was analyzed with multivariable regression models. The influence of intraoperative RBC transfusion on the effect of preoperative anemia on outcomes was studied using mediation analysis. RESULTS: Anemia was present in 25% of patients. Anemic patients had a higher STS Predicted Risk of Operative Mortality (1.2% vs 0.7%; P < .001). Anemia was associated with operative mortality (odds ratio [OR], 1.27; 99.5% CI, 1.00-1.61; P = .047), postoperative RBC transfusion (OR, 2.28; 99.5% CI, 2.12-2.44; P < .001), dialysis (OR, 1.58; 99.5% CI, 1.19-2.11; P < .001), and prolonged intensive care unit and hospital length of stay. Intraoperative RBC transfusion largely mediated the effects of anemia on mortality (76%), intensive care unit stay (99%), and hospital stay, but it only partially mediated the association with dialysis (34.9%). CONCLUSIONS: Preoperative anemia is common in patients who undergo CABG and is associated with increased postoperative risks of mortality, complications, and RBC transfusion. However, most of the effect of anemia on mortality is mediated through intraoperative RBC transfusion.

Contemporary Surgical Management of Hypertrophic Cardiomyopathy.

More than half of symptomatic patients with hypertrophic cardiomyopathy (HCM) have left ventricular outflow tract (LVOT) obstruction. Septal reduction therapy by septal myectomy can dramatically relieve exertional dyspnea, chest pain, and presyncope in properly selected patients and is an important management pathway for many patients. The distribution and degree of hypertrophy in patients with obstructive HCM are variable and, as discussed in this review, can influence clinical manifestations of the disease and surgical management. Subaortic septal hypertrophy is the most common phenotype of obstructive HCM associated with LVOT obstruction, but midventricular obstruction and apical hypertrophy may occur in isolation or in conjunction with subaortic septal hypertrophy. In many comprehensive HCM centers, transaortic septal myectomy is the preferred method of septal reduction therapy for symptomatic patients with obstructive HCM. Early surgical approaches aimed at alleviating left LVOT obstruction were hampered by a lack of understanding of the anatomy and pathophysiology of obstructive HCM. With the advent of Doppler echocardiography and, more recently, cardiac magnetic resonance imaging, surgeons can precisely assess the location and degree of obstruction, left ventricular size and function, and morphology and function of the mitral valve. This review discusses the current understanding of the role of septal myectomy in the management of patients with HCM and details contemporary operative methods.

Improvement in gastrointestinal bleeding after septal myectomy for hypertrophic cardiomyopathy.

OBJECTIVE: Patients with obstructive hypertrophic cardiomyopathy may have occult gastrointestinal bleeding. In this study, we analyzed outcomes of septal myectomy in patients who had a history of gastrointestinal bleeding preoperatively to understand patient characteristics and impact of septal reduction on recurrent gastrointestinal bleeding. METHODS: We analyzed 73 adult patients who had a history of gastrointestinal bleeding before transaortic septal myectomy for obstructive hypertrophic cardiomyopathy and compared outcomes to 219 patients without gastrointestinal bleeding preoperatively. RESULTS: Patients with preoperative history of gastrointestinal bleeding were older (median (IQR) age, 65 (59-69) years, P < .001) and were more likely to have systemic hypertension (70% vs 53%, P = .020) and coronary artery disease (25% vs 13%, P = .026). Preoperatively, patients with gastrointestinal bleeding had a larger left atrial volume index (median, 53 mL/m2; interquartile range, 42-67; P = .006) and greater right ventricular systolic pressure (median, 36 mm Hg; interquartile range, 32-49; mm Hg, P = .005) but no significant difference in severity of outflow tract obstruction (P = .368). There were no perioperative deaths. The estimated 5- and 10-year survivals were 96.6% and 81.8%, respectively. At a median of 3.4 (interquartile range, 1.9-9.1) years after septal myectomy, 11 patients (15%) had recurrence of gastrointestinal bleeding, which was attributed to angiodysplasia or unknown causes in 6 patients (8%). CONCLUSIONS: Patients with a preoperative history of gastrointestinal bleeding have favorable short- and long-term outcomes after septal myectomy for obstructive hypertrophic cardiomyopathy. Remission of gastrointestinal bleeding was observed in 85% of patients postprocedure, and only 8% of the patients had recurrent gastrointestinal bleeding due to angiodysplasia or unknown causes.

Benefit of Anticoagulation Early After Surgical Aortic Valve Replacement Using Bioprosthetic Valves.

OBJECTIVE: To compare all-cause mortality and thromboembolic events in patients undergoing surgical aortic valve replacement (sAVR) receiving anticoagulation with warfarin versus patients with no systemic anticoagulation. PATIENTS AND METHODS: Using data from the OptumLabs Data Warehouse, we investigated adult patients having bioprosthetic sAVR with or without coronary artery bypass from January 1, 2007, through December 31, 2019. Patients were classified into groups of nonwarfarin or warfarin (≥30 days of continuous prescription coverage after sAVR). One-to-one propensity score (PS) matching was used to adjust for group differences. RESULTS: Of 10,589 patients having sAVR, 7659 (72.3%) were in the nonwarfarin group and 2930 (27.7%) were in the warfarin group. After PS matching, 2930 pairs of patients were analyzed. Median follow-up was 4.1 months (interquartile range [IQR], 2.6-7.4 months) for the warfarin group and 21.3 months (IQR, 7.8-24.0 months) for the nonwarfarin group. Overall mortality was lower for the warfarin group than for the nonwarfarin group (hazard ratio [HR], 0.68; 95% confidence interval [CI], 0.47 to 1.00; P=.047), and there was a trend toward decreased cumulative incidence of thromboembolic events (subdistribution HR [SHR], 0.62; 95% CI, 0.35 to 1.07; P=.09). Cumulative incidence of major bleeding events was higher for the warfarin group vs the nonwarfarin group (SHR, 1.94; 95% CI, 1.28 to 2.94; P=.002). Results were similar in a subgroup analysis of patients undergoing isolated sAVR. CONCLUSION: During the prescription coverage period, warfarin use after bioprosthetic sAVR was associated with lower all-cause mortality and decreased risk of thromboembolism compared with not receiving warfarin. However, warfarin use was associated with an increased risk of major bleeding events.

Risk factors and early outcomes of repeat sternotomy in 1960 adults with congenital heart disease: A 30-year, single-center study.

OBJECTIVE: Patients with congenital heart disease (CHD) increasingly live into adulthood, often requiring cardiac reoperation. We aimed to assess the outcomes of adults with CHD (ACHD) undergoing repeat sternotomy at our institution. METHODS: Review of our institution's cardiac surgery database identified 1960 ACHD patients undergoing repeat median sternotomy from 1993 to 2023. The primary outcome was early mortality, and the secondary outcome was a composite end point of mortality and significant morbidity. Univariable and multivariable logistic regression models were used to determine factors independently associated with outcomes. RESULTS: Of the 1960 ACHDs patient undergoing repeat sternotomy, 1183 (60.3%) underwent a second, third (n = 506, 25.8%), fourth (n = 168, 8.5%), fifth (n = 70, 3.5%), and sixth sternotomy or greater (n = 33, 1.6%). CHD diagnoses were minor complexity (n = 145, 7.4%), moderate complexity (n = 1380, 70.4%), and major complexity (n = 435, 22.1%). Distribution of procedures included valve (n = 549, 28%), congenital (n = 625, 32%), aortic (n = 104, 5.3%), and major procedural combinations (n = 682, 34.7%). Overall early mortality was 3.1%. Factors independently associated with early mortality were older age at surgery, CHD of major complexity, preoperative renal failure, preoperative ejection fraction, urgent operation, and postoperative blood transfusion. In addition, sternotomy number and bypass time were independently associated with the composite outcome. CONCLUSIONS: Despite the increase in early mortality with sternotomy number, sternotomy number was not independently associated with early mortality but with increased morbidity. Improvement strategies should target factors leading to urgent operations, early referral, along with operative efficiency including bypass time and blood conservation.

Fate of concomitant tricuspid regurgitation in patients undergoing coronary artery bypass grafting.

OBJECTIVE: Owing to a lack of supportive data, tricuspid regurgitation (TR) is usually not addressed in patients undergoing coronary artery bypass grafting (CABG). Here we evaluated changes in TR degrees over time and its impact on survival in patients undergoing CABG. METHODS: We reviewed the data of 9726 patients who underwent isolated CABG between January 2000 and January 2021. According to preoperative TR severity, patients were stratified into nonsignificant (none to trivial, mild) and significant (moderate to severe) TR groups. We excluded patients who had undergone previous tricuspid valve surgery, pacemaker placement, and concomitant valve or ablative surgery. Propensity score matching and Cox proportional hazards models were used to identify associations between TR grade and the primary outcome of all-cause mortality. The secondary outcome was change in TR severity on the last echocardiogram. RESULTS: After propensity score matching, 380 patients in each group were identified. At baseline, 359 patients had moderate TR (94.5%) and 21 (5.5%) had severe TR. On the last follow-up echocardiogram, TR had improved in 40.5% of the patients in the significant TR group. Kaplan-Meier survival curves showed significantly lower survival in patients with significant preoperative TR compared to those with nonsignificant TR (P < .001). After adjusting for other confounders, survival was no worse in the patients with significant TR group (hazard ratio, 1.05; 95% confidence interval, 0.80-1.38; P = .70). CONCLUSIONS: Significant preoperative TR improved in 40.5% of patients after isolated CABG. After adjusting for other factors, significant TR did not affect long-term survival.