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.

Intercostal Cryo Nerve Block in Minimally Invasive Cardiac Surgery: The Prospective Randomized FROST Trial.

INTRODUCTION: Intercostal cryo nerve block has been shown to enhance pulmonary function recovery and pain management in post-thoracotomy procedures. However, its benefit have never been demonstrated in minimal invasive thoracotomy heart valve surgery (Mini-HVS). The purpose of the study was to determine whether intraoperative intercostal cryo nerve block in conjunction with standard of care (collectively referred to hereafter as CryoNB) provided superior analgesic efficacy in patients undergoing Mini-HVS compared to standard-of-care (SOC). METHODS: FROST was a prospective, 3:1 randomized (CryoNB vs. SOC), multicenter trial in patients undergoing Mini-HVS. The primary endpoint was the 48-h postoperative forced expiratory volume in 1 s (FEV1) result. Secondary endpoints were visual analog scale (VAS) scores for pain at the surgical site and general pain, intensive care unit and hospital length-of-stay, total opioid consumption, and allodynia at 6 months postoperatively. RESULTS: A total of 84 patients were randomized to the two arms of the trial CryoNB (n = 65) and SOC (n = 19). Baseline Society of Thoracic Surgeons Predictive Risk of Mortality (STS PROM) score, ejection fraction, and FEV1 were similar between cohorts. A higher 48-h postoperative FEV1 result was demonstrated in the CryoNB cohort versus the SOC cohort (1.20 ± 0.46 vs. 0.93 ± 0.43 L; P = 0.02, one-sided two-sample t test). Surgical site VAS scores were similar between the CryoNB and SOC cohorts at all postoperative timepoints evaluated, but VAS scores not related to the surgical site were lower in the SOC group at 72, 94, and 120 h postoperatively. The SOC cohort had a 13% higher opioid consumption than the CryoNB cohort. One of 64 CryoNB patients reported allodynia that did not require pain medication at 10 months. CONCLUSIONS: The results of FROST demonstrated that intercostal CryoNB provided enhanced FEV1 score at 48 h postoperatively with optimized analgesic effectiveness versus SOC. Future larger prospective randomized trials are warranted to determine whether intercostal CryoNB has an opioid-sparing effect in patients undergoing Mini-HVS. TRIAL REGISTRATION: Clinicaltrials.gov identifier: NCT02922153.

Orthopedic Principles to Facilitate Enhanced Recovery After Cardiac Surgery.

Enhanced recovery after surgery (ERAS) protocols recognize early postoperative mobilization as a driver of faster postoperative recovery, return to normal activities, and improved long-term patient outcomes. For patients undergoing open cardiac surgery, an opportunity for facilitating earlier mobilization and a return to normal activity lies in the use of improved techniques to stabilize the sternal osteotomy. By following the key orthopedic principles of approximation, compression, and rigid fixation, a more nuanced approach to sternal precaution protocols is possible, which may enable earlier patient mobilization, physical rehabilitation, and recovery.

Sternotomy closure using rigid plate fixation: a paradigm shift from wire cerclage.

BACKGROUND: Rigid plate fixation (RPF) is the cornerstone in managing fractures and osteotomies except for sternotomy, where most cardiac surgeons continue to use wire cerclage (WC). Results of a multicenter randomized trial evaluating sternal healing, sternal complications, patient reported outcome measures (PROMs), and costs after sternotomy closure with RPF or WC are summarized here. METHODS: Twelve US centers randomized 236 patients to either RPF (n=116) or WC (n=120). The primary endpoint, sternal healing at 6 months, was evaluated by a core laboratory using computed tomography and a validated 6-point scale (greater scores represent greater healing). Secondary endpoints assessed through 6 months included sternal complications and PROMs. Costs from the time of sternal closure through 90 days and 6 months were analyzed by a health economic core laboratory. RESULTS: RPF compared to WC resulted in better sternal healing scores at 3 (2.6±1.1 vs. 1.8±1.0; P<0.0001) and 6 months (3.8±1.0 vs. 3.3±1.1; P=0.0007) and higher sternal union rates at 3 [41% (42/103) vs. 16% (16/102); P<0.0001] and 6 months [80% (81/101) vs. 67% (67/100); P=0.03]. There were fewer sternal complications with RPF through 6 months [0% (0/116) vs. 5% (6/120); P=0.03] and a trend towards fewer sternal wound infections [0% (0/116) vs. 4.2% (5/120); P=0.06]. All PROMs including sternal pain, upper extremity function (UEF), and quality-of-life scores were numerically better in RPF patients compared to WC patients at all follow-up time points. Although RPF was associated with a trend toward higher index hospitalization costs, a trend towards lower follow-up costs resulted in total costs that were $1,888 less at 90 days in RPF patients compared to WC patients (95% CI: -$8,889 to $4,273; P=0.52) and $1,646 less at 6 months (95% CI: -$9,127 to $4,706; P=0.61). CONCLUSIONS: Sternotomy closure with RPF resulted in significantly better sternal healing, fewer sternal complications, improved PROMs and was cost neutral through 90 days and 6 months compared to WC.

Rigid Plate Fixation Versus Wire Cerclage: Patient-Reported and Economic Outcomes From a Randomized Trial.

BACKGROUND: In a multicenter randomized trial, sternal closure after cardiac operations using rigid plate fixation (RPF) compared with wire cerclage (WC) resulted in improved sternal healing, reduced sternal complications, and was cost neutral at 6 months. Additional secondary end points are presented from this trial. METHODS: Twelve United States centers randomized 236 patients to RPF (n = 116) or WC (n = 120). Patient-reported outcomes measures, including pain, function, and quality of life scores, were assessed through 6 months and correlated to computed tomography-derived sternal healing scores using logistic regression. Cost analysis through 90 days was performed to mimic bundled care models. RESULTS: All patient-reported outcomes measures were numerically better in RPF patients than in WC patients at all assessments. RPF resulted in more patients reporting no sternal pain after coughing at 3 weeks (41.1% vs 19.6%; p = 0.001) and 6 weeks (54.5% vs 35.1%; p = 0.005) and at rest at 6 weeks (74.1% vs 58.8%; p = 0.02) and 3 months (87.6% vs 75.9%; p = 0.03) compared with WC. Better sternal healing scores correlated to having no sternal pain at rest (odds ratio, 1.6; 95% confidence interval, 1.2 to 2.2; p = 0.002) and after coughing (odds ratio, 1.6; 95% confidence interval, 1.2 to 2.2; p = 0.0007). RPF resulted in improvements in the 36-Item Short Form Health Survey quality of life scores at 3 weeks (53.5 ± 8.7 vs 50.5 ± 10.4; p = 0.03), 6 weeks (45.3 ± 8.4 vs 42.7 ± 8.4; p = 0.03), and 6 months (56.4 ± 6.8 vs 53.9 ± 9.0; p = 0.04) compared with WC. Through 90 days, RPF compared with WC was $1,888 less (95% confidence interval, -$8,889 to $4,273; p = 0.52). CONCLUSIONS: In patients undergoing sternal closure after median sternotomy, RPF compared with WC resulted in reduced sternal pain, improved upper extremity function, and similar total 90-day costs.

Randomized, multicenter trial comparing sternotomy closure with rigid plate fixation to wire cerclage.

OBJECTIVE: To evaluate sternal healing, complications, and costs after sternotomy closure with rigid plate fixation or wire cerclage. METHODS: This prospective, single-blinded, multicenter trial randomized 236 patients at 12 US centers at the time of sternal closure to either rigid plate fixation (n = 116) or wire cerclage (n = 120). The primary endpoint, sternal healing at 6 months, was evaluated by a core laboratory using computed tomography and a 6-point scale (greater scores represent greater healing). Secondary endpoints included sternal complications and costs from the time of sternal closure through 6 months. RESULTS: Rigid plate fixation resulted in better sternal healing scores at 3 (2.6 ± 1.1 vs 1.8 ± 1.0; P < .0001) and 6 months (3.8 ± 1.0 vs 3.3 ± 1.1; P = .0007) and greater sternal union rates at 3 (41% [42/103] vs 16% [16/102]; P < .0001) and 6 months (80% [81/101] vs 67% [67/100]; P = .03) compared with wire cerclage. There were fewer sternal complications through 6 months with rigid plate fixation (0% [0/116] vs 5% [6/120]; P = .03) and a trend towards fewer sternal wound infections (0% [0/116] vs 4.2% [5/120]; P = .06) compared with wire cerclage. Although rigid plate fixation was associated with a trend toward greater index hospitalization costs ($23,437 vs $20,574; P = .11), 6-month follow-up costs tended to be lower ($9002 vs $13,511; P = .14). As a result, total costs from randomization through 6 months were similar between groups ($32,439 vs $34,085; P = .61). CONCLUSIONS: Sternotomy closure with rigid plate fixation resulted in significantly better sternal healing, fewer sternal complications, and no additional cost compared with wire cerclage at 6 months after surgery.

Porcine endothelial cells and iliac arteries transduced with AdenoIL-4 are intrinsically protected, through Akt activation, against immediate injury caused by human complement.

Vascular endothelial cells (ECs) can be injured in a variety of pathologic processes that involve activated complement. We reported previously that porcine ECs incubated with exogenous IL-4 or IL-13 are protected from cytotoxicity by human complement and also from apoptosis by TNF-alpha. The resistance to complement consists of an intrinsic mechanism that is lost a few days after cytokine removal. In our current study, we investigated whether transfer of the IL-4 gene into porcine ECs in vitro and into porcine vascular tissues in vivo would induce efficient and durable protection from human complement. We found that ECs transduced with adenoIL-4 or adenoIL-13 exhibited continuous production of the cytokine and prolonged protection from complement-mediated killing. IL-4 also protected ECs from activation: ECs incubated with IL-4 did not develop cell retraction and intercellular gaps upon stimulation with sublytic complement. The endothelium and subendothelium of pig iliac arteries that were transduced with the IL-4 gene were effectively protected from complement-dependent immediate injury after perfusion with human blood. However, after similar perfusion, the endothelium was immediately lost from arteries that were transduced with a control adenovirus. The protection was not due to up-regulation of the complement regulators decay accelerating factor, membrane cofactor protein, and CD59, or to reduced complement activation, but required the participation of Akt. Although our studies model protection in pig-to-primate xenotransplantation, our findings of IL-4 induction of Akt-mediated protection may be more broadly applicable to EC injury as manifested in ischemia-reperfusion, allotransplantation, and various vascular diseases.

IL-4 and IL-13 induce protection of porcine endothelial cells from killing by human complement and from apoptosis through activation of a phosphatidylinositide 3-kinase/Akt pathway.

Vascular endothelial cells (EC) perform critical functions that require a balance of cell survival and cell death. EC death by apoptosis and EC activation and injury by the membrane attack complex of complement are important mechanisms in atherosclerosis and organ graft rejection. Although the effects of various cytokines on EC apoptosis have been studied, little is known about their effects on complement-mediated EC injury. Therefore, we studied the abilities of various cytokines to induce protection of porcine aortic EC against apoptosis and killing by human complement, a model of pig-to-human xenotransplantation. We found that porcine EC incubated with IL-4 or IL-13, but not with IL-10 or IL-11, became protected from killing by complement and apoptosis induced by TNF-alpha plus cycloheximide. Maximal protection required 10 ng/ml IL-4 or IL-13, developed progressively from 12 to 72 h of incubation, and lasted 48-72 h after cytokine removal. Protection from complement was not associated with reduced complement activation, C9 binding, or changes in CD59 expression. Inhibition of PI3K prevented development of protection; however, inhibition of p38 MAPK or p42/44 MAPK had no effect. IL-4 and IL-13 induced rapid phosphorylation of Akt. Although protection was inhibited by an Akt inhibitor and a dominant negative Akt mutant transduced into EC, it was induced by transduction of EC with the constitutively active Akt variant, myristylated Akt. We conclude that IL-4 and IL-13 can induce protection of porcine EC against killing by apoptosis and human complement through activation of the PI3K/Akt signaling pathway.