Rigid Sternal Fixation and Enhanced Recovery for Opioid-free Analgesia After Cardiac Surgery.

BACKGROUND: We evaluated the individual contributions of rigid-plate fixation (RPF) and an enhanced recovery protocol (ERP) on postoperative pain, opioid use, and other outcomes after median sternotomy as they were sequentially adopted into practice. METHODS: This single-center, retrospective, case-cohort study compared outcomes between median sternotomy patients (all comers) who underwent surgery before implementation of RPF or ERP ("Controls"), patients closed with RPF prior to ERP implementation ("RPF-only") and patients managed with RPF and ERP during early "RPF+ERP-2020" and late "RPF+ERP-2022" implementation. RESULTS: Six hundred and eight median sternotomy patients (mean age 65.7 ± 10.8 y; 29.6% female) were included in the analysis. Of those, 59.2% were isolated coronary artery bypass grafting and 7.7% were isolated valve procedures; the remainder were mixed/concomitant procedures. Median in-hospital, postoperative opioid administration was 172.5 morphine milligram equivalents in the control cohort versus 0 morphine milligram equivalents for RPF+ERP-2022 (P<.0001) despite similar or slightly reduced patient-reported pain scores. The proportion of patients discharged directly to home was 66.2% for controls versus 79.6% for RPF-only (P=.010) and 93.5% for RPF+ERP-2022 (P<.0001). Median opioids prescribed at discharge were 600 morphine milligram equivalents for controls versus 0 for RPF+ERP-2020 and RPF+ERP-2022 (P<.0001); 86.7% of RPF-only patients received prescription opioids at discharge versus 5% and 4.3% in RPF+ERP-2020 and RPF+ERP-2022, respectively (P<.0001). These outcomes occurred without increased readmissions. CONCLUSIONS: Systematic implementation of RPF and ERP was associated with a significant and clinically meaningful decrease in opioid use in this large, real-world patient population.

Implementing a Preoperative Anemia Optimization Protocol for Cardiovascular Surgery Patients: A Quality Improvement Project.

BACKGROUND: Patients with anemia have poorer outcomes following cardiac surgery than do those without anemia. To improve outcomes, the Enhanced Recovery After Surgery cardiac recommendations include optimizing patients' condition, including treating anemia, before surgery. LOCAL PROBLEM: Despite implementing Enhanced Recovery After Surgery initiatives, a midwestern cardiothoracic surgery group recognized a care gap in preoperative patients with anemia. No standardized protocol was in use. METHODS: An anemia optimization protocol was developed for perioperative care of patients with anemia. Data from retrospective medical record review were analyzed to determine relationships between protocol use and secondary outcomes. The protocol was created using best evidence and expert consensus. Cardiac surgery and hematology specialists revised the protocol and agreed on a final version. The protocol was integrated into the consultation process for cardiac surgery patients. RESULTS: During the implementation period, 23 of 55 patients with anemia (42%) received interventions via the anemia optimization protocol. The mean quantity of packed red blood cells transfused perioperatively per patient was 1.9 U in the protocol group and 3.5 U in the nonprotocol group. In the subgroup of patients experiencing postoperative acute kidney injury, the mean increase in creatinine level was 0.65 mg/dL in the protocol group and 1.52 mg/dL in the nonprotocol group. Four patients in the protocol group (17%) and 6 patients in the nonprotocol group (19%) experienced postoperative acute kidney injury. CONCLUSION: Preoperative anemia is associated with poorer cardiac surgical outcomes. Incorporating the anemia optimization protocol into practice may mitigate the risk of postoperative complications for patients with anemia. Continued use of the protocol is recommended.

Low-dose warfarin with a novel mechanical aortic valve: Interim registry results at 5-year follow-up.

OBJECTIVES: To evaluate whether warfarin targeted at an international normalized ratio of 1.8 (range, 1.5-2.0) after On-X mechanical aortic valve implant is safe for all patients. METHODS: This prospective, observational clinical registry assessed adverse event rates in adult patients receiving low-dose warfarin (target international normalized ratio, 1.8; range, 1.5-2.0) plus daily aspirin (75-100 mg) during a 5-year period after On-X aortic valve implant. The primary end point is the combined rate of major bleeding, valve thrombosis, and thromboembolism overall and in 4 subgroups. The comparator is the Prospective Randomized On-X Anticoagulation Trial control group patients on standard-dose warfarin (international normalized ratio, 2.0-3.0) plus aspirin 81 milligrams daily. RESULTS: A total of 510 patients were recruited at 23 centers in the United States, United Kingdom, and Canada between November 2015 and January 2022. This interim analysis includes 229 patients scheduled to complete 5-year follow-up by August 16, 2023. The linearized occurrence rate (in percent per patient-year) of the primary composite end point of major bleeding, valve thrombosis, and thromboembolism is 1.83% compared with 5.39% (95% confidence interval, 4.12%-6.93%) in the comparator group. Results are consistent in clinic-monitored and home-monitored patients and in those at high risk for thromboembolism. Major bleeding and total bleeding were reduced by 87% and 71%, respectively, versus the comparator group, without an increase in thromboembolic events. CONCLUSIONS: Interim results support the continued safety of the On-X aortic mechanical valve with a target international normalized ratio of 1.8 plus low-dose aspirin through 5 years after implant, with or without home monitoring.

On-X aortic valve replacement patients treated with low-dose warfarin and low-dose aspirin.

OBJECTIVES: To assess if warfarin targeted to international normalized ratio (INR) 1.8 (range 1.5-2.0) is safe for all patients with an On-X aortic mechanical valve. METHODS: This prospective, observational registry follows patients receiving warfarin targeted at an INR of 1.8 (range 1.5-2.0) plus daily aspirin (75-100 mg) after On-X aortic valve replacement. The primary end point is a composite of thromboembolism, valve thrombosis and major bleeding. Secondary end points include the individual rates of thromboembolism, valve thrombosis and major bleeding, as well as the composite in subgroups of home or clinic-monitored INR and risk categorization for thromboembolism. The control was the patient group randomized to standard-dose warfarin (INR 2.0-3.0) plus daily aspirin 81 mg from the PROACT trial. RESULTS: A total of 510 patients were enroled at 23 centres in the UK, USA and Canada. Currently, the median follow-up duration is 3.4 years, and median achieved INR is 1.9. The primary composite end point rate in the low INR patients is 2.31% vs 5.39% (95% confidence interval 4.12-6.93%) per patient-year in the PROACT control group, constituting a 57% reduction. Results are consistent in subgroups of home or clinic-monitored, and high-risk patients, with reductions of 56%, 57% and 57%, respectively. Major and total bleeding are decreased by 85% and 73%, respectively, with similar rates of thromboembolic events. No valve thrombosis occurred. CONCLUSIONS: Interim results suggest that warfarin targeted at an INR of 1.8 (range 1.5-2.0) plus aspirin is safe and effective in patients with an On-X aortic mechanical valve with or without home INR monitoring.

Pacemaker implantation after concomitant tricuspid valve repair in patients undergoing minimally invasive mitral valve surgery: Results from the Mini-Mitral International Registry.

Objective: Randomized evidence suggests a high risk of pacemaker implantation for patients undergoing mitral valve (MV) surgery with concomitant tricuspid valve repair (cTVR). We investigated the impact of cTVR on outcomes in the Mini-Mitral International Registry. Methods: From 2015 to 2021, 7513 patients underwent minimally invasive MV with or without cTVR in 17 international centers (MV: n = 5609, cTVR: n = 1113). Propensity matching generated 1110 well-balanced pairs. Multivariable analysis was applied. Results: Patients with cTVR were older and had more comorbidities. Propensity matching eliminated most differences except for more TR in patients who underwent cTVR (77.2% vs 22.1% MV, P < .001). Mean matched age was 71 years, and 45% were male. European System for Cardiac Operative Risk Evaluation II was still 2.68% (interquartile range [IQR], 0.80-2.63) vs 1.9% (IQR, 1.12-3.9) in matched MV (P < .001). MV replacement (30%) and atrial fibrillation surgery (32%) were similar in both groups. Cardiopulmonary bypass (161 minutes [IQR, 133-203] vs MV: 130 minutes [IQR, 103-166]; P < .001) and crossclamp times (93 minutes [IQR, 66-123] vs MV: 83 minutes [IQR, 64-107]; P < .001) were longer with cTVR. Although in-hospital mortality was similar (cTVR: 3.3% vs MV: 2.2%; P = .5), postoperative pacemaker implantations (9% vs MV: 5.8%; P = .02), low cardiac output syndrome (7.7% vs MV: 4.4%; P = .02), and acute kidney injury (13.8% vs MV: 10%; P = .01) were more frequent with cTVR. cTVR eliminated relevant TR in most patients (greater-than-moderate TR: 6.8%). Multivariable analysis identified MV replacement, atrial fibrillation, and cTVR as risk factors of postoperative pacemaker implantation. Conclusions: cTVR in minimally invasive MV surgery is an independent risk factor for pacemaker implantation in this international registry. It is also associated with more bleeding, low output syndrome, and acute kidney injury. It remains unclear whether technical or patient factors (or both) explain these differences.

Neurological outcomes in minimally invasive mitral valve surgery: risk factors analysis from the Mini-Mitral International Registry.

OBJECTIVES: The aim of this study was to examine the incidence and predictors of stroke after minimally invasive mitral valve surgery (mini-MVS) and to assess the role of preoperative CT scan on surgical management and neurological outcomes in the large cohort of Mini-Mitral International Registry. METHODS: Clinical, operative and in-hospital outcomes in patients undergoing mini-MVS between 2015 and 2021 were collected. Univariable and multivariable analyses were used to identify predictors of stroke. Finally, the impact of preoperative CT scan on surgical management and neurological outcomes was assessed. RESULTS: Data from 7343 patients were collected. The incidence of stroke was 1.3% (n = 95/7343). Stroke was associated with higher in-hospital mortality (11.6% vs 1.5%, P < 0.001) and longer intubation time, ICU and hospital stay (median 26 vs 7 h, 120 vs 24 h and 14 vs 8 days, respectively). On multivariable analysis, age (odds ratio 1.039, 95% confidence interval 1.019-1.060, P < 0.001) and mitral valve replacement (odds ratio 2.167, 95% confidence interval 1.401-3.354, P < 0.001) emerged as independent predictors of stroke. Preoperative CT scan was made in 31.1% of cases. These patients had a higher risk profile and EuroSCORE II (median 1.58 vs 1.1, P < 0.001). CT scan influenced the choice of cannulation site, being ascending aorta (18.5% vs 0.5%, P < 0.001) more frequent in the CT group and femoral artery more frequent in the no CT group (97.8% vs 79.7%, P < 0.001). No difference was found in the incidence of postoperative stroke (CT group 1.5, no CT group 1.4%, P = 0.7). CONCLUSIONS: Mini-MVS is associated with a low incidence of stroke, but when it occurs it has an ominous impact on mortality. Preoperative CT scan affected surgical cannulation strategy but did not led to improved neurological outcomes.

State of the art: Proceedings of the American Association for Thoracic Surgery Enhanced Recovery After Cardiac Surgery Summit.

Despite the benefits established for multiple surgical specialties, enhanced recovery after surgery has been underused in cardiac surgery. A cardiac enhanced recovery after surgery summit was convened at the 102nd American Association for Thoracic Surgery annual meeting in May 2022 for experts to convey key enhanced recovery after surgery concepts, best practices, and applicable results for cardiac surgery. Topics included implementation of enhanced recovery after surgery, prehabilitation and nutrition, rigid sternal fixation, goal-directed therapy, and multimodal pain management.

Aortic cross-clamp time correlates with mortality in the mini-mitral international registry.

OBJECTIVES: Minimally invasive access has become the preferred choice in mitral and/or tricuspid valve surgery. Reported outcomes are at least similar to classic sternotomy although aortic cross-clamp times are usually longer. METHODS: We analysed the largest registry of mitral and/or tricuspid valve surgery patients (mini-mitral international registry (MMIR)) for the relationship between aortic cross-clamp times, mortality and other outcomes. From 2015 to 2021, 7513 consecutive patients underwent mini-mitral and/or tricuspid valve surgery in 17 international Heart-Valve-Centres. Data were collected according to Mitral Valve Academic Research Consortium (MVARC) definitions and 6878 patients with 1 cross-clamp period were analysed. Uni- and multivariable regression analyses were used to assess outcomes in relation to aortic cross-clamp times. RESULTS: Median age was 65 years (57% male). Median EuroSCORE II was 1.3% (Inpatient Quality Reporting (IQR): 0.80-2.63). Minimally invasive access was either by direct vision (28%), video-assisted (41%) or totally endoscopic/robotic (31%). Femoral cannulation was used in 93%. Three quarters were repairs with 17% additional tricuspid valve surgery and 19% Atrial Fibrillation (AF)-ablation. Cardiopulmonary bypass and cross-clamp times were 135 min (IQR: 107-173) and 85 min (IQR: 64-111), respectively. Postoperative events were death (1.6%), stroke (1.2%), bleeding requiring revision (6%), low cardiac output syndrome (3.5%) and acute kidney injury (6.2%, mainly stage I). Statistical analyses identified significant associations between cross-clamp time and mortality, low cardiac output syndrome and acute kidney injury (all P < 0.001). Age, low ejection fraction and emergent surgery were risk factors, but variables of 'increased complexity' (redo, endocarditis, concomitant procedures) were not. CONCLUSIONS: Aortic cross-clamp time is associated with mortality as well as postoperatively impaired cardiac and renal function. Thus, implementing measures to reduce cross-clamp time may improve outcomes.

Risk-related clinical outcomes after minimally invasive mitral valve surgery: insights from the Mini-Mitral International Registry.

OBJECTIVES: With the popularization of catheter-based mitral valve procedures, evaluating risk-specific differentiated clinical outcomes after contemporary mitral valve surgery is crucial. In this study, we assessed the operative results of minimally invasive mitral valve operations across different patient risk profiles and evaluated the value of EuroSCORE (ES) II predicted risk of mortality model for risk prediction, in the large cohort of Mini-Mitral International Registry (MMIR). METHODS: The MMIR database was used to analyse mini-mitral operations between 2015 and 2021. Patients were categorized as low (<4%), intermediate (4% to <8%), high (8% to <12%) and extreme risk (≥12%) according to ES II. The observed-to-expected mortality ratio was calculated for each risk group. RESULTS: A total of 6541 patients were included in the analysis. Of those, 5546 (84.8%) were classified as low risk, 615 (9.4%) as intermediate risk, 191 (2.9%) as high risk and 189 (2.9%) as extreme risk. Overall operative mortality and stroke rates were 1.7% and 1.4%, respectively, and were significantly associated with patient's risk. The observed mortality was significantly lower than expected-according to the ES II-in all risk categories (observed-to-expected ratio < 1). CONCLUSIONS: The present study provides an international contemporary benchmark for operative outcomes after minimally invasive mitral surgery. Operative results were excellent in low-, intermediate- and high-risk patients, but were less satisfactory in extreme risk. The ES II model overestimated the in-hospital mortality. We believe that findings from the MMIR may assist surgeons and cardiologists in clinical decision-making and treatment allocation for patients with mitral valve disease.

Low-Dose vs Standard Warfarin After Mechanical Mitral Valve Replacement: A Randomized Trial.

BACKGROUND: Current guidelines recommend a target international normalized ratio (INR) range of 2.5 to 3.5 in patients with a mechanical mitral prosthesis. The Prospective Randomized On-X Anticoagulation Clinical Trial (PROACT) Mitral randomized controlled noninferiority trial assessed safety and efficacy of warfarin at doses lower than currently recommended in patients with an On-X (Artivion, Inc) mechanical mitral valve. METHODS: After On-X mechanical mitral valve replacement, followed by at least 3 months of standard anticoagulation, 401 patients at 44 North American centers were randomized to low-dose warfarin (target INR, 2.0-2.5) or standard-dose warfarin (target INR, 2.5-3.5). All patients were prescribed aspirin, 81 mg daily, and encouraged to use home INR testing. The primary end point was the sum of the linearized rates of thromboembolism, valve thrombosis, and bleeding events. The design was based on an expected 7.3% event rate and 1.5% noninferiority margin. RESULTS: Mean patient follow-up was 4.1 years. Mean INR was 2.47 and 2.92 (P <.001) in the low-dose and standard-dose warfarin groups, respectively. Primary end point rates were 11.9% per patient-year in the low-dose group and 12.0% per patient-year in the standard-dose group (difference, -0.07%; 95% CI, -3.40% to 3.26%). The CI >1.5%, thus noninferiority was not achieved. Rates (percentage per patient-year) of the individual components of the primary end point were 2.3% vs 2.5% for thromboembolism, 0.5% vs 0.5% for valve thrombosis, and 9.13% vs 9.04% for bleeding. CONCLUSIONS: Compared with standard-dose warfarin, low-dose warfarin did not achieve noninferiority for the composite primary end point. (PROACT Clinicaltrials.gov number, NCT00291525).

Apixaban or Warfarin in Patients with an On-X Mechanical Aortic Valve.

BACKGROUND: Vitamin K antagonists are the only oral anticoagulants approved to prevent valve thrombosis and valve-related thromboembolism in patients with mechanical heart valves. Whether patients with an On-X mechanical aortic valve can be safely anticoagulated with apixaban is unknown. METHODS: Patients with an On-X aortic valve implanted at least 3 months before enrollment were randomly assigned to receive apixaban 5 mg twice daily or warfarin (target international normalized ratio 2.0 to 3.0). The primary efficacy end point was the composite of valve thrombosis or valve-related thromboembolism with coprimary analyses comparing apixaban with warfarin for noninferiority and comparing the apixaban event rate with an objective performance criterion (OPC). RESULTS: The trial was stopped after 863 participants were enrolled owing to an excess of thromboembolic events in the apixaban group. Most (94%) participants took aspirin. A total of 26 primary end-point events occurred, 20 (in 16 participants) in the apixaban group (4.2%/patient-year; 95% confidence interval [CI], 2.3 to 6.0) and 6 (in 6 participants) in the warfarin group (1.3%/patient-year; 95% CI, 0.3 to 2.3). The difference in primary end-point rates between the apixaban and warfarin groups was 2.9 (95% CI, 0.8 to 5.0); noninferiority and OPC success criteria were not met. Major bleeding rates were 3.6%/patient-year with apixaban and 4.5%/patient-year with warfarin. CONCLUSIONS: Apixaban did not demonstrate noninferiority to warfarin and is less effective than warfarin for the prevention of valve thrombosis or thromboembolism in patients with an On-X mechanical aortic valve. (Funded by Artivion; ClinicalTrials.gov number, NCT04142658.)

Advanced artificial intelligence-guided hemodynamic management within cardiac enhanced recovery after surgery pathways: A multi-institution review.

Objective: The study objective was to report early outcomes of integrating Hypotension Prediction Index-guided hemodynamic management within a cardiac enhanced recovery pathway on total initial ventilation hours and length of stay in the intensive care unit. Methods: A multicenter, historical control, observational analysis of implementation of a hemodynamic management tool within enhanced recovery pathways was conducted by identifying cardiac surgery cases from 3 sites during 2 time periods, August 1 to December 31, 2019 (preprogram), and April 1 to August 31, 2021 (program). Reoperations, emergency (salvage), or cases requiring mechanical assist were excluded. Data were extracted from electronic medical records and chart reviews. Two primary outcome variables were length of stay in the intensive care unit (using Society of Thoracic Surgeons definitions) and acute kidney injury (using modified Kidney Disease Improving Global Outcomes criteria). One secondary outcome variable, total initial ventilation hours, used Society of Thoracic Surgeons definitions. Differences in length of stay in the intensive care unit and total ventilation time were analyzed using Kruskal-Wallis and stepwise multiple linear regression. Acute kidney injury stage used chi-square and stepwise cumulative logistic regression. Results: A total of 1404 cases (795 preprogram; 609 program) were identified. Overall reductions of 6.8 and 4.4 hours in intensive care unit length of stay (P = .08) and ventilation time (P = .03) were found, respectively. No significant association between proportion of patients identified with acute kidney injury by stage and period was found. Conclusions: Adding artificial intelligence-guided hemodynamic management to cardiac enhanced recovery pathways resulted in associated reduced time in the intensive care unit for patients undergoing nonemergency cardiac surgery across institutions in a real-world setting.

Prophylactic Left Atrial Appendage Exclusion in Cardiac Surgery Patients With Elevated CHA2DS2-VASc Score: Results of the Randomized ATLAS Trial.

OBJECTIVE: Patients with elevated CHA2DS2-VASc scores are at high risk for atrial fibrillation (AF) and thromboembolic events (TE) after cardiac surgery. Left atrial appendage exclusion (LAAE) is a permanent, continuous approach to stroke prevention in AF, overcoming limitations of oral anticoagulation (OAC). We report ATLAS trial results focused on LAAE technical success and perioperative safety and TE rates with and without LAAE in cardiac surgery patients who developed postoperative AF (POAF). METHODS: ATLAS (NCT02701062) was a prospective, multicenter, feasibility trial. Patients age ≥18 years, undergoing structural heart procedure, with no preoperative AF, CHA2DS2-VASc ≥2, and HAS-BLED ≥2 were randomized 2:1 to LAAE or no LAAE. Patients who developed POAF and/or received LAAE were followed for 1 year. LAAE was evaluated with intraoperative transesophageal echocardiography. RESULTS: A total of 562 patients were randomized to LAAE (n = 376) or no LAAE (n = 186). Mean CHA2DS2-VASc (3.4 vs 3.4) and HAS-BLED (2.8 vs 2.9) scores were similar for LAAE and no LAAE groups. LAAE success (no flow nor residual stump >10 mm) was 99%. One LAAE-related serious adverse event (0.27%) occurred and was resolved without sequelae. There were 44.3% of patients who developed POAF. Through 1 year, 3.4% of LAAE patients and 5.6% of no LAAE patients had TE. OAC was used by 32.5% of POAF patients. Bleeding was higher with OAC than without (16.1% vs 5.4%, P = 0.008). CONCLUSIONS: ATLAS demonstrated a high rate of successful LAAE with low LAAE-related serious adverse events in cardiac surgery patients. Study results should be considered in future trial design to further evaluate prophylactic LAAE for stroke prevention in cardiac surgery patients with elevated stroke risk.

Early results of geometric ring annuloplasty for bicuspid aortic valve repair during aortic aneurysm surgery.

Objectives: Geometric ring annuloplasty has shown promise during bicuspid aortic valve repair for aortic insufficiency. This study examined early outcomes of bicuspid aortic valve repair associated with proximal aortic aneurysm replacement. Methods: From September 2017 to November, 2021, 127 patients underwent bicuspid aortic valve repair with concomitant proximal aneurysm reconstruction. Patient age was 50.6 ± 12.7 years (mean ± standard deviation), male gender was 83%, New York Heart Association Class was 2 (1-2) (median [interquartile range]), and preoperative aortic insufficiency grade was 3 (2-4). Ascending aortic diameter was 50 (46-54) mm, and all patients had ascending aortic replacement. Forty patients had sinus diameters greater than 45 mm, prompting remodeling root procedures. A total of 105 patients had Sievers type 1 valves, 3 patients had type 0, and 7 patients had type 2. A total of 118 patients had primarily right/left fusion, 8 patients had right/nonfusion, and 1 patient had left/nonfusion. Leaflet reconstruction used central leaflet plication and cleft closure, with limited ultrasonic decalcification in 31 patients. Results: Ring size was 23 (21-23) mm, and 26 of 40 root procedures were selective nonfused sinus replacements. Aortic clamp time was 139 (112-170) minutes, and bypass time was 178 (138-217) minutes. Postrepair aortic insufficiency grade was 0 (0-0) (P < .0001), and mean valve gradient was 10 (7-14) mm Hg. No early and 1 late mortality occurred. Four patients required reoperation for bleeding, and 4 patients required pacemakers. At a mean follow-up of 20 months (maximal 93), there were no valve-related complications, 5 late repair failures prompting valve replacement, and 1 death due to Coronavirus Disease 2019. Conclusions: Geometric ring annuloplasty for bicuspid aortic valve repair with proximal aortic aneurysm reconstruction is safe and associated with good early outcomes. Further experience and follow-up will help inform long-term durability.

Mid-term outcomes of concomitant Cox-Maze IV: Results from a multicenter prospective registry.

BACKGROUND: Benefits of concomitant atrial fibrillation (AF) surgical treatment are well established. Cardiac societies support treating AF during cardiac surgery with a class I recommendation. Despite these guidelines, adoption has been inconsistent. We report results of routine performance of concomitant Cox-Maze IV (CMIV) from participating centers using a standardized, prospective registry. METHODS: Nine surgeons at four cardiac surgery programs enrolled 807 patients undergoing concomitant CMIV surgery over 12 years. Lesions were created using bipolar radiofrequency clamps and cryoablation probes. Follow-up occurred at 3- and 6-months, then annually for 3 years. Freedom from AF was defined as no episode >30 s of atrial arrhythmia. RESULTS: Sixty-four percent of patients were male, mean age 69 years, mean left atrial size 4.6 cm, mean preoperative AF duration 4.0 years, mean EuroSCORE 6.4, and mean CHADS2 score 3.1. Thirty-day postoperative mortality and neurologic event rates were 3.3% and 1.3%, respectively. New pacemaker implant rate was 6.3%. Freedom from AF rates at 1- and 3-years stratified by preoperative AF type were: paroxysmal 94.6% and 87.5%, persistent 82.1% and 81.9%, and longstanding persistent 84.1% and 78.1%. At 3-year follow up, 84% of patients were off antiarrhythmic drugs and 74% of sinus rhythm patients were off oral anticoagulants. CONCLUSIONS: Routine CMIV is safe and effective. Acceptable outcomes can be achieved across multiple centers and multiple operators even in a moderate risk patient population undergoing more complex procedures. Surgeons and institutions should be encouraged by all cardiac societies to adopt the CMIV procedure to maximize patient benefit.

The role of mechanical valves in the aortic position in the era of bioprostheses and TAVR: Evidence-based appraisal and focus on the On-X valve.

Patients who need a prosthetic aortic heart valve may decide, working with their cardiologist and cardiac surgeon, among a variety of options: surgical or transcatheter approach, bioprosthetic or mechanical valve, or a Ross procedure if suitable to their age and anatomy. This review article examines the evidence for survival benefit with mechanical aortic valves, discusses bioprosthetic structural valve degeneration and its consequences, and considers the risks of redo aortic valve surgery or subsequent valve-in-valve (ViV) transcatheter intervention. It highlights the unique characteristics of the On-X aortic valve, including the US Food and Drug Administration approved and American College of Cardiology/American Heart Association guideline supported reduced anticoagulation target INR of 1.5 to 2.0, and discusses the PROACT Xa trial comparing apixaban vs warfarin anticoagulation. The choice of prosthetic valve should be individualized, carefully considering each patient's unique circumstances. In that context, the On-X aortic valve offers a potential lifetime solution without need for a repeat operation, while minimizing the risks of long-term anticoagulation. In an era of enthusiasm for bioprosthetic and transcatheter-based approaches, the option of a second-generation bileaflet mechanical valve with optimized hemodynamics-the On-X aortic valve-may well align with patient expectations.