Increasing Adoption of Left Atrial Appendage Occlusion in Isolated Coronary Artery Bypass Grafting.

BACKGROUND: Recent randomized trial data showed fewer strokes with left atrial appendage occlusion (LAAO) following cardiac surgery in patients with atrial fibrillation. We developed a quality initiative to increase LAAO adoption. METHODS: Among 11,099 patients undergoing isolated CABG between January 2019-March 2021 at 33 hospitals in Michigan, those with atrial fibrillation undergoing first-time, on-pump CABG were eligible (n=1,241). A goal LAAO rate of 75% was selected as a quality improvement target through a statewide collaborative. An interrupted time series analysis evaluated the change in LAAO rate before (January-December 2019) versus after (January 2020-March 2021) implementation. RESULTS: Implementation of the quality metric improved LAAO rate from 61% (357/581) before to 79% (520/660) after implementation (p<0.001). Compared to patients not undergoing concomitant LAAO, LAAO patients (71%, 877/1,241) were older, more frequently male, and had a lower STS-PROM (2.9±3.5% vs. 3.7±5.7%, p=0.003), while other baseline characteristics including CHA2DS2-VASc scores were similar. Mean bypass and cross-clamp times were 7 and 6 minutes longer, respectively, in the LAAO group among those who did not undergo concomitant ablation. Operative mortality, major morbidity, blood product administration, and thromboembolic events were similar between groups. Interrupted time series analysis showed a significant increase in LAAO rate after implementation (p=0.009). CONCLUSIONS: LAAO in patients with atrial fibrillation undergoing isolated CABG did not add operative risk versus isolated CABG without LAAO. A statewide quality improvement initiative was successful in increasing the rate of concomitant LAAO and could be further evaluated as a potential quality metric in cardiac surgery.

Risk of Pacemaker Implantation After Degenerative Mitral and Concomitant Tricuspid Valve Surgery.

BACKGROUND: A recent multicenter trial showed a reduction in tricuspid regurgitation (TR) progression when tricuspid annuloplasty was performed at the time of surgery for degenerative mitral regurgitation (MR), but with a 14% pacemaker (PPM) rate. We present real-world outcomes at a high-volume center for degenerative MR surgery with/without tricuspid annuloplasty. METHODS: Patients undergoing first-time degenerative mitral surgery between 2011-2021 were identified (n=1,738). After excluding patients undergoing aortic, aortic valve, or tricuspid replacement procedures, patients were stratified into mitral surgery alone (n=1,068) versus mitral surgery plus tricuspid annuloplasty (n=417). Outcomes including operative mortality, new PPM implantation, and postoperative length of stay as well as risk-adjusted overall mortality were compared. RESULTS: Among 1,485 patients in this study, 98% underwent mitral repair. Compared to concomitant tricuspid annuloplasty patients, those undergoing mitral surgery alone were 6 years younger and had lower median STS PROM. Among concomitant tricuspid repair patients, 85% (355/417) had moderate or less preoperative TR, while 15% (61/417) had severe TR. Operative mortality was 1.4%. The incidence of new PPM implantation was 0.7% (7/1,068) in the mitral only group and 5.5% (23/417) in the concomitant tricuspid group (p<0.001). Although unadjusted cumulative survival was lower in the concomitant tricuspid group, after risk adjustment, concomitant tricuspid surgery was not associated with worse overall mortality (HR 0.80 [95% CI, 0.53-1.19], p=0.27). CONCLUSIONS: Concomitant tricuspid annuloplasty is safe, with no difference in mortality and a less than 6% PPM rate at a high-volume mitral center. These data provide real-world context for concomitant tricuspid annuloplasty.

Evaluation of sex differences in the receipt of concomitant atrial fibrillation procedures during nonmitral cardiac surgery.

OBJECTIVE: Women are less likely to receive guideline-recommended cardiovascular care, but evaluation of sex-based disparities in cardiac surgical procedures is limited. Receipt of concomitant atrial fibrillation (AF) procedures during nonmitral cardiac surgery was compared by sex for patients with preoperative AF. METHODS: Patients with preoperative AF undergoing coronary artery bypass grafting and/or aortic valve replacement at any of the 33 hospitals in Michigan from 2014 to 2022 were included. Patients with prior cardiac surgery, transcatheter AF procedure, or emergency/salvage status were excluded. Hierarchical logistic regression identified predictors of concomitant AF procedures, account for hospital and surgeon as random effects. RESULTS: Of 5460 patients with preoperative AF undergoing nonmitral cardiac surgery, 24% (n = 1291) were women with a mean age of 71 years. Women were more likely to have paroxysmal (vs persistent) AF than men (80% vs 72%; P < .001) and had a higher mean predicted risk of mortality (5% vs 3%; P < .001). The unadjusted rate of concomitant AF procedure was 59% for women and 67% for men (P < .001). After risk adjustment, women had 26% lower adjusted odds of concomitant AF procedure than men (adjusted odds ratio, 0.74; 95% CI, 0.64-0.86; P < .001). Female sex was the risk factor associated with the lowest odds of concomitant AF procedure. CONCLUSIONS: Women are less likely to receive guideline recommended concomitant AF procedure during nonmitral surgery. Identification of barriers to concomitant AF procedure in women may improve treatment of AF.

Sex-Based Differences in Concomitant Tricuspid Repair During Degenerative Mitral Surgery.

BACKGROUND: Women with mitral valve disease have higher rates of tricuspid regurgitation (TR) than men. Although tricuspid valve repair (TVr) decreases the progression of TR, we hypothesize that there may be sex-based differences in concomitant TVr at the time of mitral valve operations. METHODS: Adults undergoing mitral valve operation for degenerative disease with moderate or worse preoperative TR at a high-volume center from 2014 to 2023 were identified. Patients with a previous tricuspid intervention were excluded. A multivariable logistic regression identified predictors of concomitant TVr. To evaluate the clinical impact of not performing TVr, a competing risk model compared development of severe TR or valve-related reoperation by sex among patients without TVr. RESULTS: Most included patients were women (55% [n = 214 of 388]), and the median age was 73 years (quartile 1-quartile 3, 65-79 years). There was no difference in the rate of severe TR by sex (female, 28%; male, 26%; P = .63). The unadjusted rate of concomitant TVr was 57% for women and 73% for men (P < .001). Overall, women had 52% lower adjusted odds of TVr (adjusted odds ratio, 0.48; 95% CI, 0.29-0.81; P = .006), including a lower adjusted rate for moderate TR (47% [95% CI, 45%-49%] vs 66% [95% CI, 64%-69%]) and for severe TR (83% [95% CI, 81%-86] vs 92% [95% CI, 90%-93%]) Among those without TVr, 12% of women and 0% of men had severe TR or required a valve-related reoperation at 4 years (P < .001). CONCLUSIONS: Women with moderate or severe TR undergoing mitral valve operation for degenerative disease were less likely to receive concomitant TVr, severe TR was more likely to develop, or they would more likely need a valve-related reoperation. Evaluation of sex-based treatment differences is imperative to improve outcomes for women.

Does Sustained Reduction of Functional Mitral Regurgitation Impact Survival?

Functional mitral regurgitation (FMR) is associated with increased mortality and has been considered a marker for advanced heart disease, yet the value of mitral valve repair (MVr) in this population remains unclear. This study aims to evaluate the impact of reducing FMR burden through surgical MVr on survival. Patients with severe FMR who underwent MVr with an undersized, complete, rigid, annuloplasty between 2004 and 2017 were assessed (n = 201). Patients were categorized based on grade of recurrent FMR (0-4). Time-to-event Kaplan-Meier estimations of freedom from death or reoperation were performed using the log-rank test. Cox proportional hazards models evaluated all-cause mortality and reported in hazards ratios (HR) and 95% confidence intervals (CI). Patients were categorized by postoperative recurrent FMR: 45% (91/201) of patients had grade 0, 29% (58/201) grade 1, 20% (40/201) grade 2, 2% (4/201) grade 3%, and 4% (8/201) grade 4. The cumulative incidence of reoperation with death as a competing risk was higher in patients with grades ≥3 recurrent FMR compared to grades ≤2 (44.6% vs 14.6%, subhazard ratio 3.69 [95% CI, 1.17-11.6]; P = 0.026). Overall freedom from death or reoperation was superior for recurrent FMR grades ≤2 compared to grades ≥3 (log-rank P < 0.001). Increasing recurrent FMR grade was independently associated with mortality (HR 1.30 [95% CI, 1.07-1.59] P = 0.009). Reduced postoperative FMR grade resulted in an incrementally lower risk of death or reoperation after MVr. These results suggest that achieving a durable reduction in FMR burden improves long-term survival.

Should mitral valve replacement age guidelines be lowered due to better bioprosthetic mitral valve durability?

OBJECTIVE: Guideline recommendations for mechanical or bioprosthetic valve for mitral valve replacement by age remains controversial. We sought to determine bovine pericardial valve durability by age and risk of reintervention. METHODS: This retrospective study between 2 large university-based cardiac surgery programs examined patients who underwent bioprosthetic mitral valve replacement from 2004 to 2020. Follow-up was obtained through June 2022. Durability outcomes involving structural valve deterioration were compared by age decile. RESULTS: Of 1544 available patients, mean age was 66 ± 13 years and 652 (42%) were aged less than 65 years. Indications for mitral valve replacement were as follows: mitral regurgitation greater than 2+ in 53% (n = 813), mitral stenosis in 44% (n = 650), endocarditis in 18% (n = 277), and reoperation in 39% (n = 602). Concomitant procedures were aortic valve replacement in 28% (n = 426), tricuspid valve in 36% (n = 550), and coronary artery bypass in 19% (n = 290). Thirty-day mortality was 5.4%. In follow-up (clinical: median [interquartile range] 75 [25-129] months), reoperation for endocarditis and new stroke were low (0.30 and 1.06 per 100 patient/years, respectively). The cumulative incidence of mitral valve reintervention for structural valve deterioration among all patients was 6.2% at 10 years and 9.0% at 12 years with no statistical difference in structural valve deterioration in patients aged 40 to 70 years (P = .1). In 90 patients with mitral valve reintervention, 30-day mortality after reintervention was 4.7% (n = 2) for 43 with mitral valve-in-valve and 6.4% (n = 3) for 47 with reoperation. CONCLUSIONS: Bovine pericardial mitral valve replacement is a durable option for younger patients. The opportunity to avoid anticoagulation and the associated risks with mechanical mitral valve replacement may be of benefit to patients. These insights may provide data needed to revise the current guidelines.

Postoperative atrial fibrillation in mitral valve surgery is not benign.

OBJECTIVE: Postoperative atrial fibrillation (POAF) is common after cardiac surgery and is often considered to be benign despite recent data suggesting worse outcomes. There are no guidelines for the amount of POAF that triggers anticoagulation or for postoperative surveillance. We examined the rate of POAF, incidence of neurologic events, development of permanent atrial fibrillation, and mortality in patients undergoing isolated mitral valve surgery at a Mitral Foundation reference center. METHODS: This is a retrospective cohort study of 922 adult patients from 2011 to 2022 with no preoperative history of arrhythmias. Multivariable logistic regression was used to identify independent risk factors for the primary outcomes. Kaplan-Meier analysis and Cox proportional-hazards model were used to characterize long-term survival. RESULTS: The incidence of POAF was 39%. Median follow-up was 4.9 months (interquartile range, 1.1-42.6 months). Diabetes (odds ratio [OR], 2.2; 95% CI, 1.2-4.1; P = .01) and increasing age (OR, 1.1; 95% CI, 1.0-1.1; P < .001) were risk factors for POAF, whereas New York Heart Association functional class was not. POAF was a risk factor for the development of permanent atrial fibrillation (OR, 3.2; 95% CI 1.9-5.4; P < .001), which was associated with increased risk of neurologic events (OR, 3.8; 95% CI, 1.5-9.7; P = .004). Ultimately, patients with POAF had worse unadjusted (P < .001) and adjusted long-term mortality (hazard ratio, 1.8; 95% CI, 1.1-3.1; P = .03). CONCLUSIONS: POAF is associated with an increased rate of neurologic events, portends development of permanent atrial fibrillation, and is associated with worse long-term survival. POAF is not benign and carries a long-term mortality implication.

Transcatheter Left Atrial Appendage Exclusion: Preclinical and Early Clinical Results With the Laminar Device.

BACKGROUND: The Laminar device rotates and closes the left atrial appendage (LAA) using an integrated ball and lock that excludes and eliminates the LAA pouch. There is a low device surface area, minimizing the risk of peridevice leak (PDL) and device-related thrombus (DRT) formation. OBJECTIVES: This study evaluates the safety and efficacy of the Laminar LAA exclusion device in healthy animals and human subjects with nonvalvular atrial fibrillation at risk of ischemic stroke and systemic thromboembolism. METHODS: The preclinical study implanted the Laminar device into canine subjects that underwent transesophageal echocardiography (TEE) and fluoroscopic evaluation, followed by necropsy and histological assessment at 45 and 150-days post-implant. The early clinical study implanted the device in human subjects, followed to 12 months postimplantation. Procedural success was defined as device implantation in the intended location without residual LAA leak >5 mm as seen by TEE. Safety endpoints included freedom from stroke, systemic embolism, pericardial effusion, or tamponade, life-threatening/major bleeding, or death. RESULTS: The Laminar device was successfully implanted in 10 canines. In all animals at 45 days and 150 days, no PDL or DRT was found, and histological examination showed fully closed LAAs covered with neo-endocardium. The device was successfully implanted in 15 human subjects with no safety events out to 12 months postimplantation. All subjects had successful protocol-defined LAA closure without DRT at 45 days by TEE and computed tomography, which remained stable through 12 months' follow-up. CONCLUSIONS: The preclinical and early clinical results demonstrate a promising safety and efficacy profile for the Laminar LAA exclusion device.

Racial disparities in mitral valve surgery: A statewide analysis.

OBJECTIVE: Racial disparities in health care have come to the forefront. We hypothesized that Black race was associated with worse preoperative risk, lower repair rates, and worse outcomes among patients who underwent mitral valve surgery. METHODS: All patients who underwent mitral valve repair or replacement with or without coronary artery bypass grafting from 2011 to 2020 in a statewide collaborative database were stratified into 3 racial groups, White, Black, and other. Preoperative characteristics, procedure type, and outcomes were evaluated. RESULTS: A total of 9074 mitral valve operations were performed at 33 centers (Black 1009 [11.1%], White 7862 [86.6%]). Preoperative combined Society of Thoracic Surgeons morbidity and mortality was higher for Black patients (Black 32%, White 22%, other 23%, [P < .001]) because of a greater proportion of diabetes, hypertension, and chronic lung disease. White patients were more likely to undergo mitral repair (White 66%, Black 53.3%, other 57%; P < .001). Operative mortality was similar across racial groups (White 3.7%, Black 4.6%, other 4.5%; P = .36). After adjusting for preoperative factors, mitral etiology, and hospitals, race was not associated with mitral valve repair, complications, or mortality, but Black patients had higher odds of extended care facility utilization and readmission. CONCLUSIONS: Contrary to our hypothesis, there was no difference in the odds of repair or operative mortality across races after accounting for risk and etiology. However, Black patients were more likely to be readmitted after discharge. These findings support a greater focus on reducing disparities in mitral valve surgery.

Cardiac Reoperations in Patients With Transcatheter Aortic Bioprosthesis.

BACKGROUND: Despite the rapid adoption of transcatheter aortic valve replacement (TAVR), the frequency and clinical outcomes of reoperation after TAVR are not well-described. METHODS: Between 2011 and 2020, 1719 patients underwent a TAVR at our institution. Among these, 32 patients (2%) required a reoperation. Additionally, 16 patients who received a TAVR at another institution received a reoperation at our institution. We retrospectively reviewed these 48 patients. The median interval from TAVR to reoperation was 2.3 years. RESULTS: Primary reoperations included 37 TAVR valve explants (TAVR-explant; 77%) with surgical aortic valve replacement (SAVR), 8 mitral repairs/replacements (17%), 2 coronary artery bypass grafting procedures (4%), and 1 tricuspid valve replacement (2%). Forty-nine percent of nonaortic valve cardiac lesions were present at the time of TAVR. Furthermore, 18 TAVR-explant patients (49%) were deemed anatomically unsuitable for repeat TAVR based on the index TAVR imaging. During TAVR-explant, 6 patients (13%) with native TAVR sustained various degrees of aortic trauma. Patients with unplanned aortic repair demonstrated a smaller sinotubular junction diameter than those without unplanned repair. In contrast, no unplanned aortic repair was needed in the 14 patients with previous SAVR or the latest 20 consecutive patients. The overall in-hospital mortality was 15%, with an observed-to-expected morality ratio of 1.8. CONCLUSIONS: The clinical impact of post-TAVR reoperation remains substantial despite the lower frequency of unplanned aortic repair over time. The necessity of reoperations or unfavorable repeat TAVR anatomy appears predictable at the time of the index TAVR, and implanters must be mindful of "lifetime management" strategy during candidate selection.

Contemporary Management of Ischemic Mitral Regurgitation at Coronary Artery Bypass Grafting.

BACKGROUND: Recent guidelines for the treatment of moderate or severe ischemic mitral regurgitation (IMR) in patients undergoing coronary artery bypass grafting (CABG) have changed. This study assessed the real-world impact of changing guidelines on the management of IMR during CABG over time. We hypothesized that the utilization of mitral valve repair for IMR would decrease over time, whereas mitral valve replacement for severe IMR would increase. METHODS: Patients undergoing CABG in a statewide collaborative database (2011-2020) were stratified by severity of IMR. Trends in mitral valve repair or replacement were evaluated. To account for differences of the patients, propensity score-matched analyses were used to compare patients with and without mitral intervention. RESULTS: A total of 11,676 patients met inclusion criteria, including 1355 (11.6%) with moderate IMR and 390 (3.3%) with severe IMR. The proportion of patients undergoing mitral intervention for moderate IMR decreased over time (2011, 17.7%; 2020, 7.5%; Ptrend = .001), whereas mitral replacement for severe IMR remained stable (2011, 11.1%; 2020, 13.3%; Ptrend = .14). Major morbidity was higher for patients with moderate IMR who underwent mitral intervention (29.1% vs 19.9%; P = .005). In a propensity analysis of 249 well-matched pairs, there was no difference in major morbidity (29.3% with mitral intervention vs 23.7% without; P = .16) or operative mortality (1.2% vs 2.4%; P = .5). CONCLUSIONS: Consistent with recent guideline updates, patients with moderate IMR were less likely to undergo mitral repair. However, the rate of replacement for severe IMR did not change. Mitral intervention during CABG did not increase operative mortality or morbidity.

Repeat crossclamp after failed initial degenerative mitral valve repair is safe and successful.

Objective: Surgical risk and long-term outcomes when re-crossclamp is required during degenerative mitral valve repair are unknown. We examined the outcomes of patients who required re-crossclamp for mitral valve reintervention. Methods: Adults undergoing mitral valve repair for degenerative mitral valve disease at a single center from 2007 to 2021 who required more than 1 crossclamp for mitral valve reintervention were included. Outcomes including major morbidity and 30-day mortality were collected. Kaplan-Meier analysis characterized survival and freedom from recurrent mitral regurgitation. Results: A total of 69 patients required re-crossclamp for mitral valve reintervention. Of those, 72% (n = 50) underwent successful re-repair and the remaining underwent mitral valve replacement (28%, n = 19). Major morbidity occurred in 23% (n = 16). There was no 30-day mortality, and median long-term survival was 10.9 years for those undergoing re-repair and 7.2 years for those undergoing replacement (P = .79). Midterm echocardiography follow-up was available for 67% (33/50) of patients who were successfully re-repaired with a median follow-up of 20 (interquartile range, 7-37) months. At late follow-up, 90% of patients had mild or less mitral regurgitation. Of those re-repaired, 2 patients later required mitral valve reintervention. Conclusions: Patients requiring re-crossclamp for residual mitral regurgitation had low perioperative morbidity and no mortality. Most patients underwent successful re-repair (vs mitral valve replacement) with excellent valve function and long-term survival. In the event of unsatisfactory repair at the time of mitral valve repair, attempt at re-repair is safe and successful with the appropriate valvar anatomy.

Alfieri versus conventional repair for bileaflet mitral valve prolapse.

Objective: Mitral valve repair for bileaflet prolapse can be complex, involving multiple chords or resection. The Alfieri technique for bileaflet disease is simple but may be associated with mitral stenosis or recurrent mitral regurgitation. Outcomes of patients with bileaflet prolapse undergoing mitral valve repair using the Alfieri versus conventional chord/resection techniques were compared. Methods: Adults undergoing mitral valve repair for bileaflet prolapse for degenerative disease from 2017 to 2023 were stratified by repair technique. Outcomes including operative mortality and echocardiogram data were compared. Time to event analysis was used to characterize freedom from recurrent mitral regurgitation (moderate or greater mitral regurgitation). Results: Among 188 patients with bileaflet prolapse, 37% (70) were repaired with the Alfieri and the remaining patients were repaired with chords/resection. Compared with chords/resection, patients undergoing the Alfieri had shorter cardiopulmonary bypass and crossclamp times. Operative mortality (0% [0/70] vs 2% [2/118], P = .27) was similar between both techniques. The mean mitral gradient was low and similar for the Alfieri versus chords/resection (3 vs 3, P = .34). Development of recurrent mitral regurgitation at 2 years, incorporating the competing risk of death and mitral reintervention, was 4.3% (95% CI, 1.5%-9.3%) for the Alfieri technique and 5.8% (95% CI, 2.2%-11.8%) for chord/resection (P = .83). Conclusions: Both the Alfieri and chord/resection techniques had low rates of recurrent mitral regurgitation at 2 years. The mitral valve gradient was low and similar regardless of technique; thus, those who received the Alfieri technique did not have an increased rate of mitral stenosis. The Alfieri may be an underused technique for bileaflet prolapse.

Surgical outcomes of patients at prohibitive risk who are reconsidered for surgery.

Objectives: Transcatheter treatment of advanced mitral and tricuspid valve disease is largely limited to patients at prohibitive surgical risk, although many are not candidates for transcatheter treatment. Here, we describe surgical outcomes of patients at prohibitive risk who were ineligible for transcatheter therapies to guide surgeons in management of this unique population. Methods: Patients at prohibitive risk, defined per surgeon or cardiologist discretion, who were initially referred for a transcatheter mitral or tricuspid intervention in a multidisciplinary atrioventricular valve clinic, were identified from 2019 to 2022. Preoperative risk, operative outcomes, and long-term mortality were evaluated. Results: A total of 337 patients at prohibitive risk were referred for evaluation in a multidisciplinary atrioventricular valve clinic. Of those, 161 underwent transcatheter therapy, 130 patients underwent continued medical management, and 45 were reevaluated and had high-risk surgery. Among surgical patients, 51% were women with a median age of 76 years (quartile 1-quartile 3, 65-81 years). Most patients presented in heart failure (83%; n = 37 out of 45), and 73% were in New York Heart Association functional class III or IV. Most patients (94%; n = 43) had a mitral valve intervention, of whom 56% (24 out of 43) had a mitral valve replacement. The 30-day mortality rate was 4% (2 out of 45) and major morbidity occurred in 33% (15 out of 45). By Kaplan-Meier analysis, 1-year survival was 86% ± 9%. Conclusions: Select patients at prohibitive risk who were ineligible for transcatheter mitral or tricuspid valve intervention underwent surgery with overall low operative mortality and excellent 1-year survival. Patients a prohibitive risk whose anatomy is not amenable to transcatheter devices should be reconsidered for surgery.