Open Chest Surgery Research Articles

Factors contributing to severe scoliosis after open chest surgery for congenital heart disease: a case-control analysis.

Previous reports have identified factors associated with open chest surgery for congenital heart disease (CHD) and scoliosis. However, these reports included conditions such as Down syndrome and Marfan syndrome, which involve both cardiac disease and scoliosis. The relationships between these factors and open chest surgery remain unclear. This study aimed to identify factors contributing to severe scoliosis in CHD patients who have undergone open chest surgery. Seventy-four post-CHD surgery patients with severe scoliosis (Scoliosis group) and 30 post-CHD surgery patients without scoliosis (NS group), excluding those with any syndrome or intellectual disability, were retrospectively analyzed. Patient background characteristics and radiographic parameters were compared between the NS and Scoliosis groups. Furthermore, the patients in the Scoliosis group were classified into three categories, namely, mild scoliosis, moderate scoliosis, and severe scoliosis, and the results were compared among the four groups. Eighteen patients in the NS group and 63 in the Scoliosis group met the inclusion criteria. Compared with the NS group, the Scoliosis group included significantly more girls and patients who had younger ages at first CHD surgery and multiple open chest surgeries. Severe scoliosis progression was observed in patients who underwent multiple surgeries for severe CHD with cardiomegaly. Progression to severe scoliosis was noted in patients with younger ages at first CHD surgery and those who underwent multiple surgeries for severe CHD. Assessing spinal deformities should be a key aspect of postoperative care for CHD, particularly in patients with severe CHD who are undergoing multiple chest surgeries. III.

Abstract 4136085: The Prognostic Impact of Thrombocytopenia at 6 months after Transcatheter Aortic Valve Replacement: A Retrospective Multicenter Study

Background: Transient thrombocytopenia after transcatheter aortic valve replacement (TAVR) is a common phenomenon. Thrombocytopenia after TAVR during the perioperative period has been reported to impact prognosis. However, the impact of thrombocytopenia in the mid-term post-TAVR period is currently unknown. Methods: A retrospective observational study was conducted on 1405 patients who underwent TAVR from May 2016 to February 2023 at four institutions. Of these, 850 patients were analyzed. Patients who underwent dialysis (67), converted to an open chest surgery (8), had a Valve-in-Valve procedure (30), underwent a direct aortic approach (16), had a malignant tumor (66), and patients whose platelet levels could not be measured at 6 months after TAVR due to death or dropout were excluded from the analysis. The clinical follow-up occurred at 1, 6, and 12 months after the procedure. Laboratory testing was conducted before TAVR, during the perioperative period, 1 month post-procedure, and 6 months later. The decrease in platelet count (DPC) 6 months after TAVR was calculated by the following formula: [(Baseline platelet – 6 months platelet)/baseline platelet *100]. A receiver operating characteristics curve was plotted for all-cause mortality at 1 year and DPC at 6 months. The calculated cutoff value for the DPC at 6 months (28.68%) was utilized to classify and compare the two groups. Multivariate logistic regression models were also used to examine the association between the DPC at 6 months and all-cause mortality at 1 year. Adjusted for propensity score matching, the DPC was compared at 6 months in self-expandable and balloon-expandable prosthetic valves. Result: Of the 850 eligible patients (age: 85.5 ± 4.9 years), 31 (3.4%) died between 6 months and 1 year after TAVR. The DPC at 6 months after TAVR was 11.9 ± 22.5%. Multivariate logistic regression analysis including the DPC at 6 months, age, gender, and STS score showed that the DPC at 6 months was independently associated with all-cause mortality at 1 year (odds ratio: 1.03, 95% confidence interval: 1.005-1.046, p=0.01). After adjustment for propensity score matching, the balloon-expandable prosthetic valve had a higher rate of thrombocytopenia at 6 months (15.0% vs. 9.6%, p=0.04). Conclusion: The DPC at 6 months after TAVR may predict all-cause mortality at 1 year.

Abstract 4137925: Long-term Outcome of Initial Thoracic Endovascular Repair or Medical Therapy in Acute Uncomplicated Type B Aortic Dissection: Real-world Data from a Nationwide Claims-Database in Japan.

Introduction: Thoracic endovascular aortic repair (TEVAR) has emerged as a promising treatment option for patients with type B aortic dissection (TBAD). However, there is a lack of evidence regarding the long-term morbidity of initial TEVAR compared to optimal medical therapy (OMT) in acute uncomplicated TBAD (uTBAD). Objective: To evaluate real-world data(RWD) on the long-term outcome of Japanese patients with acute uTBAD using a nationwide claims database. Methods: This retrospective cohort study utilizes JMDC, a nationwide claims database under Japan's universal healthcare system. We included patients who were initially hospitalized with a diagnosis of acute TBAD. We defined acute uTBAD by excluding those who died within one month, suffered aortic rupture, traumatic thoracic aortic injury, underwent open-chest surgery, experienced stroke or paralysis, or had less than six months of history in the JMDC. Patients who underwent TEVAR within three months of the index hospitalization (TEVAR group) were compared with those who received optimal medical therapy (OMT group). Propensity score (PS) matching was performed based on age, sex, and year of hospitalization. Using the Kaplan-Meier method, we calculated the cumulative rate of all-cause mortality and aorta-related events. Results: Of 18,445 patients diagnosed with aortic disease between January 2005 and December 2020, 641 were included in the study (OMT group: n=580, TEVAR group: n=61). After PS-matching, demographics of the groups (OMT_PSM: n=183 vs. TEVAR_PSM: n=61) were female (12.6% vs. 13.1%), median age (54 years [IQR, 48-60] vs. 54 years [IQR, 50-61]) and follow-up time (18 months [8-32] vs. 19 months [9-32]), respectively. Kaplan-Meier curves for the aortic-related events (Figure1, 2) are shown as long-term outcomes. Conclusions: This study successfully demonstrated that the estimated 5-year aortic-related event rate in acute uTBAD patients undergoing OMT is approximately 20%, demonstrating the relevance of the RWD source. However, the number of death events in the TEVAR and OMT groups was not sufficient to provide statistical power. Therefore, further studies are warranted to evaluate the long-term prognosis of initial TEVAR for uTBAD.

Ultrasound-Based Cardiac Output Monitoring During Pediatric Open-Heart Surgery in Children

Aim of the study. To evaluate the feasibility of using non-invasive hemodynamic monitoring technology based on Doppler ultrasound during open-heart surgery in children.Material and methods. Prospective, observational, single-center cohort study included 20 patients aged 10 to 34 months undergoing surgery for congenital heart defects. Ten patients underwent atrial septal defect closure (ASD group), other 10 patients had ventricular septal defect closure (VSD group). Cardiac output (CO) was measured in all patients to guide inotropic and infusion therapy adjustments at three control time points: (1) after intubation and before skin incision, (2) during the immediate post-bypass period with the chest open after weaning from cardiopulmonary bypass (CPB), and (3) after sternal closure and before transfer to the intensive care unit (ICU).Results. At time point 1, the CO values for both the ASD and VSD groups were within the normal reference range: 5.2 L/min [4.7; 5.5] and 5.1 L/min [4.6; 5.6], respectively. At time point 2, CO was measured in 15 of 20 patients, including 8 patients in the ASD group and 7 in the VSD group. Coverage was 75% because of the challenges of measuring 5 patients on the operating table. In the immediate post-bypass period, two patients with VSD (25%) developed hypotension with CO reduced to 3.6 L/min, which is lower than the age-related hemodynamic reference value (5.1 L/min). Inotropic support in these two patients was increased by switching from dopamine, 7 mcg/kg/min, to adrenaline at a dose of 0.05 mcg/kg/min, resulting in improvement of hemodynamic parameters and an increase in CO to 5.2 L/min and 5.0 L/min, respectively, compared to normal agerelated reference values (4.1; 6.1 L/min). After sternal closure, CO values in both groups did not differ significantly from age-related reference values.Conclusion. The USCOM cardiac output monitoring device can be used to manage intraoperative hemodynamics and adjust inotropic therapy even during open chest surgery. However, its routine use in all stages of surgery with median sternotomy is difficult because it requires more time to align the aortic valve projection.

Efficacy and safety of therapeutic alpha-1-microglobulin RMC-035 in reducing kidney injury after cardiac surgery: a multicentre, randomised, double-blind, parallel group, phase 2a trial

Cardiac surgery invariably triggers acute kidney stress causing adverse renal outcomes. The AKITA study evaluated the efficacy and safety of RMC-035, a novel analogue of alpha-1-microglobulin, for reducing cardiac surgery-associated kidney injury. In this randomised double-blind placebo-controlled phase 2a study, we randomly assigned (1:1) adult hospitalised patients undergoing open-chest cardiac surgery at high risk for acute kidney injury (AKI) at 21 sites in North America and Europe to receive either RMC-035 (1.3 or 0.65mg/kg) or placebo (1:1) for 2 days (5 intravenous infusions), stratified by region and renal function. Eligible patients had at least one pre-defined AKI risk factor. Patients with severe renal impairment (estimated glomerular filtration rate [eGFR] <30mL/min/1.73m2) were excluded. The co-primary efficacy and safety endpoints were AKI (Kidney Disease: Improving Global Outcomes definition) within 72h after surgery and nature, frequency, and severity of treatment-emergent adverse events (TEAEs). Secondary endpoints included eGFR and Major Adverse Kidney Events (MAKE) up to Day 90. Randomised patients who had received at least one dose of study drug were analysed for primary and safety analyses. Participants, investigators and sponsor were masked to treatment allocation. This study is registered at ClinicalTrials.gov (NCT05126303) and EudraCT (2021-004040-19). Patient enrolment was stopped at interim analysis due to futility. Between March 31, 2022 and July 12, 2023, 177 patients (RMC-035: 89, placebo: 88) were randomised and treated. AKI rate for RMC-035 vs placebo was 50.6% (n=45) and 39.8% (n=35) (relative risk [RR]: 1.30, 90% confidence interval [90% CI]: 0.99, 1.71; p=0.12). A short-lived creatinine increase was observed with the higher RMC-035 dose. Treatment with RMC-035 was associated with improved secondary renal outcomes at Day 90: placebo-adjusted eGFR change from baseline 4.3mL/min/1.73m2, 90% CI 0.51-8.12, p=0.06; and MAKE 6.7% (n=6) vs 15.9% (n=14); RR: 0.41, 90% CI: 0.19, 0.88, p=0.05. The most frequently reported TEAEs for RMC-035 were chills (30.3%), nausea (21.3%), anaemia (20.2%); and atrial fibrillation (29.5%), anaemia (20.5%), hypervolemia (14.8%) for placebo. The majority of TEAEs in both treatment groups were mild or moderate in severity. In the RMC-035 group, 26 (29.2%) patients experienced at least one severe or life-threatening TEAE and in the placebo group 16 (18.2%) patients. There were 4 deaths per treatment arm (one treatment-related, in placebo group). In this proof-of-concept study, RMC-035 did not reduce AKI 72h after cardiac surgery. Evaluations may have been confounded by a drug-induced transient creatinine increase in a subgroup of patients. RMC-035 was associated with improved secondary renal outcomes. These results merit further investigation and should be interpreted with caution, as the study was not powered for these outcomes. Guard Therapeutics.

Early diagnosis to avoid invasive treatment in cardiac migration of a ventriculoperitoneal catheter: a qualitative systematic review and Weibull analysis of case reports

OBJECTIVE The migration of distal catheter after ventriculoperitoneal shunt placement is a rare but significant complication. Especially in a case of cardiac migration, open-heart surgery or catheter intervention may be required. The authors encountered a case of cardiac migration that fortunately could be treated by withdrawal. A systematic review of cardiac migration was performed to clarify when and how migration was diagnosed and why invasive treatments were required. Based on the collected cases, a Weibull analysis of the latency until diagnosis was performed to examine whether cardiac migration is caused by an initial factor and to compare the result with the other migration sites such as gastrointestinal tract or urinary tract. METHODS A qualitative systematic review was performed according to the Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) guidelines. A database of case reports was created by searching PubMed and Scopus with the keywords "ventriculoperitoneal AND shunt AND migration" (last search date: April 2022). Whether the occurrence rate of migration is constant over time was examined by fitting a Weibull distribution. RESULTS A total of 339 articles of all migration sites were identified. Among them, 36 articles reporting 38 cases of cardiac migration were considered eligible. A total of 39 cases including the authors’ case were reviewed qualitatively. When classifying the cases by their latency to diagnosis, the rates of pulmonary thrombosis and of cardiac adhesion were higher in the delayed group (≥ 1 year) than in the early group (≤ 1 month). The rate of open chest surgery was higher in the delayed, intermediate, and early groups, in that order. In the Weibull analysis, the shape parameter (β) was less than 1, indicating that the occurrence rate of cardiac migration was initially high, followed by a decline. The finding supports the hypothesis that migration results from an intraoperative vascular injury. Note that these findings are subject to bias given that they are derived from case reports. CONCLUSIONS In light of the previous reports, the latency until diagnosis of cardiac migration was associated with the rate of thrombosis and adhesion, which resulted in escalation to invasive treatment. Early diagnosis will prevent invasive treatment because most cases are caused by initial factors, as the Weibull analysis showed.

Coronary bypass surgery for multivessel disease after percutaneous coronary intervention in acute coronary syndromes: why, for whom, how early?

Multivessel coronary artery disease is present in ∼50% of patients with acute coronary syndrome and, compared with single-vessel disease, entails a higher risk of new ischaemic events and a worse prognosis. Randomized controlled trials have shown the superiority of 'complete revascularization' over culprit lesion-only treatment. Trials, however, only included patients treated with percutaneous coronary intervention (PCI), and evidence regarding complete revascularization with coronary artery bypass graft (CABG) surgery after culprit lesion-only PCI ('hybrid revascularization') is lacking. The CABG after PCI is an open, non-negligible therapeutic option, for patients with non-culprit left main and/or left anterior descending coronary artery disease where evidence in chronic coronary syndrome patients points in several cases to a preference of CABG over PCI. This valuable but poorly studied 'PCI first-CABG later' option presents, however, relevant challenges, mostly in the need of interrupting post-stenting dual antiplatelet therapy (DAPT) for surgery to prevent excess bleeding. Depending on patients' clinical characteristics and coronary anatomical features, either deferring surgery after a safe interruption of DAPT or bridging DAPT interruption with intravenous short-acting antithrombotic agents appears to be a suitable option. Off-pump minimally invasive surgical revascularization, associated with less operative bleeding than open-chest surgery, may be an adjunctive strategy when revascularization cannot be safely deferred and DAPT is not interrupted. Here, the rationale, patient selection, optimal timing, and adjunctive strategies are reviewed for an ideal approach to hybrid revascularization in post-acute coronary syndrome patients to support physicians' choices in a case-by-case patient-tailored approach.

Simple model of pulmonary hypertension secondary to left heart pressure overload induced by partial intravascular occlusion of the ascending aorta.

Pulmonary hypertension is a group of diseases characterized by elevated pulmonary artery pressure and pulmonary vascular resistance with significant morbidity and mortality. The most prevalent type is pulmonary hypertension secondary to left heart disease (PH-LHD). The available experimental models of PH-LHD use partial pulmonary clamping by technically nontrivial open-chest surgery with lengthy recovery. We present a simple model in which the reduction of the cross-sectional area of the ascending aorta is achieved not by external clamping but by partial intravascular obstruction without opening the chest. In anesthetized rats, a blind polyethylene tubing was advanced from the right carotid artery to just above the aortic valve. The procedure is quick and easy to learn. Three weeks after the procedure, left heart pressure overload was confirmed by measuring left ventricular end-diastolic pressure by puncture (1.3 ± 0.2 vs. 0.4 ± 0.3 mmHg in controls, mean ± SD, P < 0.0001). The presence of pulmonary hypertension was documented by measuring pulmonary artery pressure by catheterization (22.3 ± 2.3 vs. 16.9 ± 2.7 mmHg, P = 0.0282) and by detecting right ventricular hypertrophy and increased muscularization of peripheral pulmonary vessels. Contributions of a precapillary vascular segment and vasoconstriction to the increased pulmonary vascular resistance were demonstrated, respectively, by arterial occlusion technique and by normalization of resistance by a vasodilator, sodium nitroprusside, in isolated lungs. These changes were comparable, but not additive, to those induced by an established pulmonary hypertension model, chronic hypoxic exposure. Intravascular partial aortic obstruction offers an easy model of pulmonary hypertension induced by left heart disease that has a vasoconstrictor and precapillary component.NEW & NOTEWORTHY We present a new, simple model of a clinically important type of pulmonary hypertension, that induced by left heart failure. Left ventricular pressure overload is induced in rats by inserting a blinded cannula into the ascending aorta via carotid artery access. This partial intravascular aortic obstruction, which does not require opening of the chest and prolonged recovery, causes pulmonary hypertension, which has a precapillary and vasoconstrictor as well as a vascular remodeling component.

In the Catheterization Laboratory, Most Iatrogenic Cardiac Tamponades Require Only Pericardiocentesis: A Single-Center Experience.

Cardiac tamponade (CT) is a rare but life-threatening complication of cardiac interventions, requiring immediate pericardial cavity pressure relief. While pericardiocentesis often suffices, and some cases necessitate open-chest surgery. This decision is frequently based on individual physician's experience. This study aims to identify high-risk CT patients following cardiac intervention, advocating for early, decisive surgical intervention. A retrospective analysis was conducted on 51 patients who developed iatrogenic CT at our center between October 2013 and October 2023. Patients were classified based on the necessity for open-chest surgery. The study evaluated a variety of factors, including baseline characteristics, therapeutic approaches, and outcomes. Of the 51 patients with iatrogenic CT, 49 patients were successfully treated without open-chest surgery, with an average immediate drainage volume of 208.2 173.8 mL. In contrast, the two patients requiring open-chest surgery had significantly higher drainage volumes, exceeding 500 mL, with over 300 mL drained in the first hour, indicating laceration injuries. Patients not requiring open-chest surgery demonstrated favorable outcomes. The majority of patients with iatrogenic CT and non-lacerated injuries experienced a favorable prognosis following pericardiocentesis. However, in cases of lacerated injuries with drainage volume was above 300 mL per hour, pericardiocentesis alone could not stabilize the hemodynamics due to persistent bleeding. Immediate surgery may be needed in these cases.

Therapeutic α-1-microglobulin ameliorates kidney ischemia-reperfusion injury.

α-1-Microglobulin (A1M) is a circulating glycoprotein with antioxidant, heme-binding, and mitochondrial protection properties. The investigational drug RMC-035, a modified therapeutic A1M protein, was assessed for biodistribution and pharmacological activity in a broad set of in vitro and in vivo experiments, supporting its clinical development. Efficacy and treatment posology were assessed in various models of kidney ischemia and reperfusion injury (IRI). Real-time glomerular filtration rate (GFR), functional renal biomarkers, tubular injury biomarkers (NGAL and KIM-1), and histopathology were evaluated. Fluorescently labeled RMC-035 was used to assess biodistribution. RMC-035 demonstrated consistent and reproducible kidney protection in rat IRI models as well as in a model of IRI imposed on renal impairment and in a mouse IRI model, where it reduced mortality. Its pharmacological activity was most pronounced with combined dosing pre- and post-ischemia and weaker with either pre- or post-ischemia dosing alone. RMC-035 rapidly distributed to the kidneys via glomerular filtration and selective luminal uptake by proximal tubular cells. IRI-induced expression of kidney heme oxygenase-1 was inhibited by RMC-035, consistent with its antioxidative properties. RMC-035 also dampened IRI-associated inflammation and improved mitochondrial function, as shown by tubular autofluorescence. Taken together, the efficacy of RMC-035 is congruent with its targeted mechanism(s) and biodistribution profile, supporting its further clinical evaluation as a novel kidney-protective therapy.NEW & NOTEWORTHY A therapeutic A1M protein variant (RMC-035) is currently in phase 2 clinical development for renal protection in patients undergoing open-chest cardiac surgery. It targets several key pathways underlying kidney injury in this patient group, including oxidative stress, heme toxicity, and mitochondrial dysfunction. RMC-035 is rapidly eliminated from plasma, distributing to kidney proximal tubules, and demonstrates dose-dependent efficacy in numerous models of ischemia-reperfusion injury, particularly when administered before ischemia. These results support its continued clinical evaluation.

Efficacy and Safety of Botulinum Toxin Type A for the Prevention of Postoperative Atrial Fibrillation

BackgroundPostoperative atrial fibrillation (POAF) is associated with increased morbidity and mortality. Epicardial injection of botulinum toxin may suppress POAF. ObjectivesThis study sought to assess the safety and efficacy of AGN-151607 for the prevention of POAF after cardiac surgery. MethodsThis phase 2, randomized, placebo-controlled trial assessed the safety and efficacy of AGN-151607, 125 U and 250 U vs placebo (1:1:1), for the prevention of POAF after cardiac surgery. Randomization was stratified by age (<65, ≥65 years) and type of surgery (nonvalvular/valve surgery). The primary endpoint was the occurrence of continuous AF ≥30 seconds. ResultsAmong 312 modified intention-to-treat participants (placebo, n = 102; 125 U, n = 104; and 250 U, n = 106), the mean age was 66.9 ± 6.8 years; 17% were female; and 64% had coronary artery bypass graft (CABG) only, 12% had CABG + valve, and 24% had valve surgery. The primary endpoint occurred in 46.1% of the placebo group, 36.5% of the 125-U group (relative risk [RR] vs placebo: 0.80; 95% CI: 0.58-1.10; P = 0.16), and 47.2% of the 250-U group (RR vs placebo: 1.04; 95% CI: 0.79-1.37; P = 0.78). The primary endpoint was reduced in the 125-U group in those ≥65 years of age (RR: 0.64; 95% CI: 0.43-0.94; P = 0.02) with a greater reduction in CABG-only participants ≥65 years of age (RR: 0.49; 95% CI: 0.27-0.87; P = 0.01). Rehospitalization and rates of adverse events were similar across the 3 groups. ConclusionsThere were no significant differences in the rate of POAF with either dose compared with placebo; however, there was a lower rate of POAF in participants ≥65 years undergoing CABG only and receiving 125 U of AGN-151607. These hypothesis-generating findings require investigation in a larger, adequately powered randomized clinical trial. (Botulinum Toxin Type A [AGN-151607] for the Prevention of Post-operative Atrial Fibrillation in Adult Participants Undergoing Open-chest Cardiac Surgery [NOVA]; NCT03779841); A Phase 2, Multi-Center, Randomized, Double-Blind, Placebo-Controlled, Dose Ranging Study to Evaluate the Efficacy and Safety of Botulinum Toxin Type A [AGN 151607] Injections into the Epicardial Fat Pads to Prevent Post-Operative Atrial Fibrillation in Patients Undergoing Open-Chest Cardiac Surgery; 2017-004399-68)

Danshen and Zhizi Compatibility Alleviates Heart Injury and Cardiac Ferroptosis in Myocardial Infarction in Rats by Cyclic Adenosine Monophosphate/Protein Kinase A Signaling

Objective: To investigate the effect and mechanism of the Danshen and Zhizi Compatibility (DZ) on alleviating heart injury and cardiac ferroptosis in rats with myocardial infarction. Methods: A rat model of myocardial infarction was established by ligation of the left anterior descending artery. The rats were equally and randomly divided into 5 groups. The sham group underwent open-chest surgery without arterial ligation, while the other 4 groups underwent surgery, including 3 groups treated with low dose (4 g/kg/d), high dose (8 g/kg/d) DZ and high dose (8 g/kg/d) DZ supplemented with H-89 (0.5 mg/kg/d) respectively. The sham and myocardial infarction group received the same volume of saline. 14 days after surgery, the serum and heart tissues were harvested to detect cyclic adenosine monophosphate (cAMP) and protein kinase A (PKA) activity, heart injury and the level of ferroptosis. Results: G-protein coupled receptors (GPCRs) have a high binding affinity with the main components of DZ, which indicated that DZ probably contributed to ameliorating cardiac injury by activating downstream cyclic adenosine monophosphate (cAMP)/protein kinase A (PKA) signaling. Treatment with the high dose of DZ significantly increased cAMP concentration in the serum, PKA activity in the heart tissue and upregulated perilipin (PLIN)5 expression. DZ significantly attenuated heart injury, whereas H-89 reversed the protective effects of DZ. In addition, DZ administration inhibited ferroptosis as evidenced by reduced malondialdehyde (MDA), and 4-hydroxynonenal (4-HNE) levels. In addition, DZ increased glutathione (GSH) levels and Glutathione peroxidase (GPX)4 protein expression in heart tissue, whereas H-89 abrogated the regulatory effect of DZ. Conclusion: Our results demonstrated that DZ alleviated heart injury and cardiac ferroptosis in myocardial infarction through the cAMP-PKA signalling pathway.

Postoperative atrial fibrillation is associated with long-term morbidity and mortality in older adults: Analysis from the SWEDEHEART Registry

ObjectivesPostoperative atrial fibrillation (POAF) is the most common perioperative arrhythmia. The association of POAF with negative short-term outcomes after cardiac surgery is well understood; however, the association of POAF with long-term morbidity and mortality is not well described. We compared the risk of long-term clinical outcomes (up to 9 years postdischarge) in patients with and without POAF following open-chest cardiac surgery. MethodsThis observational, retrospective cohort study used data from the Swedish Web-system for Enhancement and Development of Evidence-based care in Heart disease Evaluated According to Recommended Therapies (SWEDEHEART) Swedish Cardiac Surgery Registry and National Board of Health and Welfare. Patients aged 55 to 90 years who underwent open-chest coronary artery bypass and/or valvular surgery between 2010 and 2019 were included. Clinical outcomes were adjusted for differences in baseline demographics and clinical history using multivariable Cox regression. ResultsA total of 30,870 patients with a mean age of 69.2 years were included in the study (no POAF, n = 20,734; POAF, n = 10,136). The median follow-up was 4.6 years. After adjustment, POAF was associated with a significantly higher risk of recurrent atrial fibrillation (hazard ratio [HR], 2.30; 95% CI, 2.21-2.41), heart failure (HR, 1.17; 95% CI, 1.10-1.25), chronic kidney disease (HR, 1.15; 95% CI, 1.07-1.24), all-cause mortality (HR, 1.11; 95% CI, 1.04-1.18), and cardiovascular mortality (HR, 1.16; 95% CI, 1.06-1.26). POAF was also associated with a numerically higher risk of ischemic stroke and major bleed, but these findings were not statistically significant after adjustment. ConclusionsThese data provide further insight into the long-term clinical outcomes associated with POAF in patients undergoing cardiac surgery.

Risk of Potential Invasive Non-Tuberculous Mycobacterial Infection in Major Cardiothoracic Surgeries.

Nontuberculous Mycobacteria (NTM) commonly colonise municipal water supplies and cause healthcare-associated outbreaks. Although the infections are rare, they are associated with high mortality. Aerosolization of NTM from colonised Heater cooler devices causes invasive infections in cardiac surgery patients. These units are widely used in open-chest heart surgery as an essential part of extracorporeal circulation but have been suggested as being a risk for infection. Water disinfection as well as effective engineering-related mitigation strategies should be designed to decrease the burden of NTM in the hospital water supply. Key Words: Nontuberculous Mycobacteria, Heater cooler devices, Endocarditis, Water, Cardiothoracic surgeries.

Analysis of drug-induced and spontaneous cardioversions reveals similar patterns leading to termination of atrial fibrillation.

The mechanisms leading to the conversion of atrial fibrillation (AF) to sinus rhythm are poorly understood. This study describes the dynamic behavior of electrophysiological parameters and conduction patterns leading to spontaneous and pharmacological AF termination. Five independent groups of goats were investigated: (1) spontaneous termination of AF, and drug-induced terminations of AF by various potassium channel inhibitors: (2) AP14145, (3) PA-6, (4) XAF-1407, and (5) vernakalant. Bi-atrial contact mapping was performed during an open chest surgery and intervals with continuous and discrete atrial activity were determined. AF cycle length (AFCL), conduction velocity and path length were calculated for each interval, and the final conduction pattern preceding AF termination was evaluated. AF termination was preceded by a sudden episode of discrete activity both in the presence and absence of an antiarrhythmic drug. This episode was accompanied by substantial increases in AFCL and conduction velocity, resulting in prolongation of path length. In 77% ± 4% of all terminations the conduction pattern preceding AF termination involved medial to lateral conduction along Bachmann's bundle into both atria, followed by anterior to posterior conduction. This finding suggests conduction block in the interatrial septum and/or pulmonary vein area as final step of AF termination. AF termination is preceded by an increased organization of fibrillatory conduction. The termination itself is a sudden process with a critical role for the interplay between spatiotemporal organization and anatomical structure.

A systematic methodology for epicardial and epiaortic echocardiography in swine research models.

Perioperative echocardiography is of paramount importance during cardiac surgery. Nonetheless, in the experimental large-animal setting, it might be challenging obtaining optimal imaging when using conventional imaging acquisition techniques, such as transthoracic and transesophageal screenings. Open-chest surgery allows epicardial echocardiographic assessment with direct contact between probe and heart, thus providing superior quality. Standard protocols regarding the use of epicardial ultrasound in swine for research purposes are lacking. Epicardial echocardiography was performed in 10 female German Landrace pigs undergoing cardiac surgery. A structured and comprehensive protocol for epicardial echocardiography was elaborated including apical, ventricular long and short axis, as well as epiaortic planes. All experiments were approved by the local board for animal welfare and conducted in accordance with the German animal protection law (TierSchG) and the ARRIVE guidelines. Systematic protocols using epicardial echocardiography may serve as an additional tool to assess cardiac dimensions and function in experimental scenarios with swine models.

Inactivation of the NLRP3 inflammasome mediates exosome-based prevention of atrial fibrillation.

Rationale: Extracellular vesicles (EVs) from human explant-derived cells injected directly into the atria wall muscle at the time of open chest surgery reduce atrial fibrosis, atrial inflammation, and atrial fibrillation (AF) in a rat model of sterile pericarditis. Albeit a promising solution to prevent postoperative AF, the mechanism(s) underlying this effect are unknown and it is not clear if this benefit is dependent on EV dose. Methods: To determine the dose-efficacy relationship of EVs from human explant-derived cells in a rat model of sterile pericarditis. Increasing doses of EVs (106, 107, 108 or 109) or vehicle control were injected into the atria of middle-age male Sprague-Dawley rats at the time of talc application. A sham control group was included to demonstrate background inducibility. Three days after surgery, all rats underwent invasive electrophysiological testing prior to sacrifice. Results: Pericarditis increased the likelihood of inducing AF (p<0.05 vs. sham). All doses decreased the probability of inducing AF with maximal effects seen after treatment with the highest dose (109, p<0.05 vs. vehicle). Pericarditis increased atrial fibrosis while EV treatment limited the effect of pericarditis on atrial fibrosis with maximal effects seen after treatment with 108 or 109 EVs. Increasing EV dose was associated with progressive decreases in pro-inflammatory cytokine content, inflammatory cell infiltration, and oxidative stress. EVs decreased NLRP3 (NACHT, LRR, and PYD domains-containing protein-3) inflammasome activation though a direct effect on resident atrial fibroblasts and macrophages. This suppressive effect was exclusive to EVs produced by heart-derived cells as application of EVs from bone marrow or umbilical cords did not alter NLRP3 activity. Conclusions: Intramyocardial injection of incremental doses of EVs at the time of open chest surgery led to progressive reductions in atrial fibrosis and inflammatory markers. These effects combined to render atria resistant to the pro-arrhythmic effects of pericarditis which is mechanistically related to suppression of the NLRP3 inflammasome.

Establishment of nonobstructive coronary microcirculatory disorders in rabbits using three established methods and a comparative study

To compare the merits and drawbacks of three approaches for establishing a rabbit model of nonobstructive coronary microcirculatory disease, namely, open thoracic subtotal ligation of coronary arteries, ultrasound-guided cardiac microsphere injection, and sodium laurate injection. New Zealand rabbits were allocated to four groups: a normal group (Blank group), an Open-chest group (Open-chest), a microsphere group (Echo-M), and a sodium laurate group (Echo-SL), each comprising 10 rabbits. The rabbits were sacrificed 24 h after the procedures, and their echocardiography, stress myocardial contrast echocardiography, pathology, and surgical times were compared. The results demonstrated varying degrees of reduced cardiac function in all three experimental groups, the Open-chest group exhibiting the most significant decline. The myocardial filling in the affected areas was visually analyzed by myocardial contrast echocardiography, revealing sparse filling at rest but more after stress. Quantitative analysis of perfusion parameters (β, A, MBF) in the affected myocardium showed reduced values, the Open-chest group having the most severe reductions. No differences were observed in stress myocardial acoustic imaging parameters between the Echo-M and Echo-SL groups. Among the pathological presentations, the Open-chest model predominantly exhibited localized ischemia, while the Echo-M model was characterized by mechanical physical embolism, and the Echo-SL model displayed in situ thrombosis as the primary pathological feature. Inflammatory responses and collagen deposition were observed in all groups, with the severity ranking of Open-chest > Echo-SL > Echo-M. The ultrasound-guided intracardiac injection method used in this experiment outperformed open-chest surgery in terms of procedural efficiency, invasiveness, and maneuverability. This study not only optimizes established cardiac injection techniques but also offers valuable evidence to support clinical investigations through a comparison of various modeling methods.

Surgically treated purulent pericarditis induced by ingested fish bone: a case report

BackgroundAspiration of fish bones is common, but perforation of the gastrointestinal tract is very rare. Once perforation occurs, fatal complications such as mediastinitis and cardiac tamponade can occur. Here, we present a case of acute pericarditis due to perforation of a fish bone.Case presentationA 66-year-old woman was referred to our hospital with shortness of breath. Blood tests showed high C-reactive protein, and contrast-enhanced computed tomography showed a large amount of pericardial fluid as well as a foreign body with high bone density in the pericardial sac. Upper gastrointestinal endoscopy showed no evidence of penetration of the esophageal or gastric mucosa. Emergency open chest surgery was performed, and the pericardial sac was filled with copious amounts of pus. The fish bone-like foreign body was found to penetrate the pericardial membrane from the diaphragmatic side. The foreign body was removed, a drainage tube was placed, and the chest was closed. After 2 weeks of postoperative antibiotics, the patient was discharged from the hospital in stable general condition. Three months after the surgery, the patient had no recurrence of pericarditis.ConclusionsWe reported a rare case of gastrointestinal perforation by a fish bone, resulting in pericardium, which was treated by surgical drainage.

Abstract 12958: Temporal Association of Systemic Inflammatory Biomarkers With Incidence of Postoperative Atrial Fibrillation After Botulinum Toxin Type A Administration in Epicardial Fat Pads

Background: A one-time injection of botulinum toxin type A (BoNT/A) in epicardial fat pads was evaluated for post-operative atrial fibrillation (POAF) in patients undergoing open-chest cardiac surgery in the Ph2 NOVA trial. Treatment with 125U BoNT/A numerically reduced the incidence of POAF in the mITT (36.5% vs 46.1%) and CABG populations (28.4% vs 40.0%), with statistical significance observed in the CABG + ≥65 years subgroup (27.5% vs 56.4%; P &lt;0.01). No significant reduction was observed in the 250U group vs placebo. Purpose: Explore systemic inflammatory biomarker changes after treatment with BoNT/A and the temporal relation to incidence of POAF. Methods: This analysis included 308 patients who received 125U BoNT/A (n=103), 250U BoNT/A (n=103), or placebo (n=102). Subgroup analysis was done for CABG (n=198), age ≥65 years (n=185), and CABG + ≥65 years (n=118). Serum samples were collected preoperatively prior to dosing on Day 1, then post-treatment on Days 2-4 to test for IL-6, IL-10, and hsCRP. A 2-sample t test was used for mean concentrations and a linear mixed model was used for fold change (FC) from baseline. Results: Baseline levels of IL-6, IL-10, and hsCRP were similar between treatment groups. Reduction of IL-6 (45.7 ± 4.4 vs 62.4 ± 5.8 pg/mL, P &lt;0.05; 10.8 vs 15.9 FC, P &lt;0.01) and IL-10 (1.49 ± 0.13 vs 2.04 ± 0.24 pg/mL, P &lt;0.05; 1.96 vs 2.66 FC, P &lt;0.01) was most significant on Day 2 in CABG patients treated with 125U vs placebo, which aligns with the highest rate and risk of POAF (Figure 1). Mean hsCRP was most significantly reduced on Day 4 in the 250U group among CABG patients (193 ± 8 vs 227 ± 10 mg/dL, P &lt;0.01) followed by 125U vs placebo (196 ± 10 vs 227 ± 10 mg/dL, P &lt;0.05); a similar dose-dependent reduction was observed by FC analysis. Conclusions: Treatment with 125U BoNT/A in cardiac surgery patients lowered the incidence of POAF vs placebo and reduced postoperative systemic IL-6 and IL-10 on Day 2, most significantly in the CABG population.