Single-Centre Experience of Surgical Myectomy for Hypertrophic Obstructive Cardiomyopathy.

BACKGROUND: Septal myectomy is the gold standard treatment for hypertrophic obstructive cardiomyopathy. This study aimed to evaluate the results from patients with hypertrophic cardiomyopathy who had undergone septal myectomy. METHODS: Data were analysed that has been prospectively collected over 7 years from 345 patients with hypertrophic cardiomyopathy who underwent septal myectomy at Meshalkin National Medical Research Center. RESULTS: Six (6) patients (1.7%) died within 30 days of surgery. The mean (standard deviation, SD) resting left ventricular outflow tract gradients reduced from 83.4 (24.2) mmHg preoperatively to 16.2 (8.5) mmHg at discharge (p < 0.001). Of the 345 patients, 329 (95.4%) attended the most recent follow-up assessments, and of these, 254 (77.2%) were categorised as New York Heart Association (NYHA) class I, 64 (19.5%) class II, and 11 (3.3%) class III. The mean overall long-term survival rate after septal myectomy was 95.7% (SD 1.7%) (95% CI, 90.0-97.9). This did not differ from the age-matched and gender-matched general population (log-rank, p = 0.109). At the last follow-up assessments, six of 67 patients who had undergone concomitant Cox-Maze IV procedures had late atrial tachyarrhythmia recurrences. A preoperative short-axis view of left atrial diameter of 57.5 mm (hazard ratio, 1.30 (95% CI, 1.03-1.65), p < 0.001) predicted late atrial tachyarrhythmias (p < 0.002). CONCLUSIONS: At this hypertrophic cardiomyopathy centre, septal myectomy is associated with low operative and early mortality rates (<2%), a low risk of early adverse events, and acceptable intermediate-term clinical and haemodynamic results.

Diepoxy- Versus Glutaraldehyde-Treated Xenografts: Outcomes of Right Ventricular Outflow Tract Reconstruction in Children.

BACKGROUND: Xenografts used for right ventricular outflow tract (RVOT) reconstruction are typically treated with glutaraldehyde. However, potential benefit of epoxy treatment was demonstrated in experimental studies. We aimed to compare diepoxy-treated bovine pericardial valved conduits (DE-PVCs) and glutaraldehyde-treated bovine pericardial valved conduits (GA-PVCs) for RVOT reconstruction in pediatric patients. METHODS: Between 2002 and 2017, 117 patients underwent RVOT reconstruction with PVC in single center: DE-PVC group, n = 39; and GA-PVC group, n = 78. After performing propensity score analysis (1:1) for the entire sample, 29 patients from the DE-PVC group were matched with 29 patients from the GA-PVC group. RESULTS: There were no conduit-related deaths. In the DE-PVC group, the freedom from conduit failure was 90.9% at four years and 54.3% at eight years postoperatively. In the GA-PVC group, it was 46.3% and 33.1%, respectively. The difference was significant (P = .037). Conduit failure was typically caused by stenosis in both groups. In the DE-PVC group, the main cause of stenosis was xenograft calcification (27.6%); while in the GA-PVC group, it was mostly due to neointimal proliferation (25.0%) and, less often, calcification (14.3%). Conduit thrombosis was the cause of replacement in 6.9% of patients from the GA-PVC group. CONCLUSIONS: Diepoxy-treated bovine pericardial valved conduit is a suitable alternative to GA-PVC for RVOT reconstruction in pediatric patients. Diepoxy-treated bovine pericardial valved conduits may be less prone to conduit failure and more resistant to neointimal proliferation and conduit thrombosis than GA-PVCs.

General Study and Gene Expression Profiling of Endotheliocytes Cultivated on Electrospun Materials.

Endothelization of the luminal surface of vascular grafts is required for their long-term functioning. Here, we have cultivated human endothelial cells (HUVEC) on different 3D matrices to assess cell proliferation, gene expression and select the best substrate for endothelization. 3D matrices were produced by electrospinning from solutions of poly(D,L-lactide-co-glycolide) (PLGA), polycaprolactone (PCL), and blends of PCL with gelatin (Gl) in hexafluoroisopropanol. Structure and surface properties of 3D matrices were characterized by SEM, AFM, and sessile drop analysis. Cell adhesion, viability, and proliferation were studied by SEM, Alamar Blue staining, and 5-ethynyl-2'-deoxyuridine (EdU) assay. Gene expression profiling was done on an Illumina HiSeq 2500 platform. Obtained data indicated that 3D matrices produced from PCL with Gl and treated with glutaraldehyde provide the most suitable support for HUVEC adhesion and proliferation. Transcriptome sequencing has demonstrated a minimal difference of gene expression profile in HUVEC cultivated on the surface of these matrices as compared to tissue culture plastic, thus confirming these matrices as the best support for endothelization.

History and Current Status of Cardiac Anesthesiology in Russia.

Anesthesiology, the branch of medicine concerning anesthesia and management of the vital functions of patients undergoing surgery, has played an important role in the development of cardiac surgery. In the middle of the last century, medical professionals had little experience in the treatment of congenital and acquired heart diseases. Progress of cardiac anesthesiology in Russia, as well as in countries across the globe, was due to requests to increase the safety of surgical procedures and to improve survival rates for the increasing number of patients with complex heart diseases. The development of cardiac surgery and anesthesiology in Russia evolved in 2 directions simultaneously in the mid-1950s. Some surgeons widely accepted the use of perfusionless hypothermia (hypothermia caused by surface cooling without perfusion); others were in favor of cardiopulmonary bypass technology. This review focuses on major historic milestones of cardiac anesthesiology in Russia, including its current status and the major problems it faces today.

A left atrial versus a biatrial lesion set for persistent atrial fibrillation ablation during open heart surgery.

OBJECTIVES: To compare the outcomes of left atrial ablation and biatrial (BA) ablation in patients with persistent and long-standing persistent atrial fibrillation undergoing open heart surgery. METHODS: Between January 2007 and December 2016, 588 consecutive patients with either persistent (20.9%) or long-standing persistent atrial fibrillation (79.1%) were enrolled in this study. To reduce between-group differences, propensity score-matched groups (156 patients/group) were obtained, with similar preoperative and perioperative characteristics. RESULTS: The propensity score-matched left atrial and BA groups did not differ regarding 30-day mortality (1.9% vs 0.6%; P = 0.617), 5-year overall survival (93.5 ± 2.2% vs 92.8 ± 2.9%, P = 0.998) or survival free from thromboembolic events (97.1 ± 2.8% vs 96.2 ± 2.7%, P = 0.309). The BA lesion set was more beneficial in terms of freedom from atrial arrhythmia recurrence (85.3 ± 4.5% vs 91.9 ± 3.1%, P = 0.049; hazard ratio 3.26; 95% confidence interval 1.33-7.99), but it was associated with higher pacemaker implantation rate (3.8% vs 17.3%; P < 0.001) due to sinus node dysfunction. There was no significant between-group difference regarding the incidence of atrioventricular conduction disturbances (3.2% vs 7.0%, respectively; P = 0.211). CONCLUSIONS: The 2 lesion sets (left atrial and BA) are associated with similar 30-day mortality, survival rates, incidences of embolic events and atrioventricular conduction disturbances. In patients with persistent atrial fibrillation, concomitant surgical ablation with BA lesion set provided better freedom from atrial arrhythmia recurrence, but BA ablation was associated with a higher incidence of sinus node dysfunction and a higher rate of pacemaker implantation.

In search of the best xenogeneic material for a paediatric conduit: an analysis of clinical data.

OBJECTIVES: In this study, we aimed to determine the incidence of reintervention and calcification of xenografts in paediatric patients who underwent placement of the right ventricle-to-pulmonary artery valved conduits. METHODS: We retrospectively analysed clinical data of paediatric patients (1 day-18 years) who underwent right ventricular outflow tract reconstruction using xenograft from 2000 to 2016 at a single centre. RESULTS: A total of 301 patients underwent the placement of 337 xenografts, including glutaraldehyde-treated bovine jugular vein (n = 171, 50.7%), glutaraldehyde-treated bovine pericardial valved conduit (n = 75, 22.3%), diepoxy-treated porcine aortic conduit (n = 58, 17.2%) and diepoxy-treated bovine pericardial valved conduit (DE-PVC) (n = 33, 9.8%). There were 284 (84.3%) primary implantations and 53 (15.7%) reimplantations. The median follow-up was 4.2 years (range 1.5 months-14.5 years). The multivariate regression analysis did not reveal statistically significant associations of the first reintervention with the type of xenograft (P = 0.78). At reintervention, calcification of the wall and/or cusps was the main cause of conduit dysfunction in 66.4% of cases. On the basis of the multivariate Cox regression analysis, xenograft types were significant predictors of reintervention caused by conduit calcification (P = 0.012). The diepoxy-treated porcine aortic conduit group had the risk of calcification 3 times higher than the glutaraldehyde-treated bovine jugular vein group (P < 0.001).The glutaraldehyde-treated bovine pericardial valved conduit and diepoxy-treated bovine pericardial valved conduit groups had the risk of calcification comparable with the glutaraldehyde-treated bovine jugular vein group in multivariate proportional hazards model (P = 0.36 and P = 0.59, respectively). CONCLUSIONS: We have not revealed significant difference in the freedom from first reintervention among types of conduit. Calcification leading to the conduit dysfunction was present in all groups; however, diepoxy-treated porcine aortic conduits demonstrated suboptimal results in terms of calcification at follow-up.

In search of the best xenogeneic material for a paediatric conduit: an experimental study.

OBJECTIVES: The development of calcification-resistant bioprosthetic materials is a very important challenge for paediatric surgery. The subcutaneous implantation in rats is the well-known first-stage model for this kind of research. Using this model, we aimed to compare calcification of the porcine aortic wall and bovine pericardium and jugular vein wall cross-linked with glutaraldehyde (GA) and ethylene glycol diglycidyl ether (DE). We also determined the efficacy of DE-preserved tissue modification with 2-(2-carboxyethylamino)ethylidene-1,1-bisphosphonic acid (CEABA). METHODS: Three groups of each biomaterial were evaluated: GA-treated, DE-treated and DE + CEABA-treated. The microstructure of non-implanted biomaterials was assessed by light microscopy after Picro Mallory staining; the phosphorus content of the DE and DE + CEABA samples was assessed by atomic emission spectrometry. Samples were implanted subcutaneously into young rats for 10 and 60 days. The explant end-point included quantitative calcification assessment by atomic absorption spectrophotometry and light microscopy examination after von Kossa staining. RESULTS: All GA-treated biomaterials had a high calcium-binding capacity (>100 µg/mg dry tissue). DE preservation decreased the vein wall and pericardium calcium content by 4- and 40-fold, respectively, but was ineffective for the aortic wall. The calculated CEABA content was almost equal in the vein wall and pericardium (17.7 and 18.5 µM/g) and slightly less in the aortic wall (15 µM/g) (P = 0.011). CEABA effectively reduced mineralization in the DE aortic wall and DE pericardium to 10.1 (7.8-21.1) and 0.95 (0.57-1.38) µg/mg but had no effect in the DE vein wall. Mineralization in the GA- and DE-treated aortic and vein walls was predominantly associated with elastin. CEABA modification decreased elastin calcification but did not block it completely. CONCLUSIONS: Each xenogeneic material requires individual anticalcification strategy. DE + CEABA pretreatment demonstrates a high mineralization-blocking efficacy for the bovine pericardium and should be employed to further develop the paediatric pericardial conduit. Aortic wall calcification cannot be blocked completely using this strategy.

Globular chitosan prolongs the effective duration time and decreases the acute toxicity of botulinum neurotoxin after intramuscular injection in rats.

Botulinum neurotoxin (BoNT) is used for an increasing number of neurological and non-neurological indications and disorders. Since the duration of action of this neurotoxin is limited, the goal of the work was to improve the pharmacological time course of BoNT. We explored the effect of several polysaccharides on the duration of action of BoNT/A1 in rat electromyography. The formulation of BoNT/A1 containing globular chitosan increased the threshold stimulation intensity almost 2 times in 30 days after injection if compared with the baseline threshold. However, conventional linear chitosan, heparin and hyaluronic acid did not have such an effect. In addition, we compared the effectiveness of different doses of BoNT/A1 (25, 50, 75, and 100 U) with globular chitosan and compared the acute toxicity of this formulation with that of BoNT/A1 in physiological saline after intramuscular injection. The results demonstrated that the dose 25 U of BoNT/A1 with globular chitosan was both effective and safe for animals after intramuscular injection. The assessed median lethal dose (LD50) for intramuscular injection in rats was 1.4 times higher for a combination of BoNT/A1 with globular chitosan than that for a solution of BoNT/A1 in physiological saline. Thus, the results of our study have provided evidence that intramuscular injection of the formulation of BoNT/A1 (25 U) containing globular chitosan in rats is safe and significantly prolongs the effective duration time of BoNT/A1.

Does mitral valve repair matter in infants with ventricular septal defect combined with mitral regurgitation?

OBJECTIVES: This study aimed to assess mitral valve function after repair of ventricular septal defect (VSD) combined with mitral regurgitation (MR) in the mid-term follow-up period, to evaluate the clinical utility of simultaneous mitral valve repair (MVR). METHODS: From June 2005 to March 2014, 60 patients with VSD and MR underwent surgical treatment. After performing propensity score analysis (1:1) for the entire sample, 46 patients were selected and divided into 2 groups: those with VSD closure and MVR (VSD + MVR, 23 patients) and those with VSD closure without mitral valve intervention (VSD only, 23 patients). The follow-up period ranged from 12 to 48 months (median 32 months; interquartile range 28-40 months). RESULTS: There was no postoperative mortality in either group. There was no significant difference in the duration of the postoperative period between groups (ventilation time, P = 0.49; inotropic support, P = 0.50). Mean cardiopulmonary bypass time and aortic cross-clamping time were significantly longer in the 'VSD + MVR' group (cardiopulmonary bypass, P = 0.023; aortic cross-clamp, P < 0.001). There was no significant difference in regurgitation area (P = 0.30) and MR grade (P = 0.76) between groups postoperatively. There was no significant difference in freedom from MR ≥ 2+ between groups (log-rank test, P = 0.28). In the 'VSD + MVR' group, 12-, 36- and 42-month freedom from MR ≥ 2+ values were 100%, 59 ± 10.4% [95% confidence interval (CI) 36.1-76.2%] and 44 ± 15% (95% CI 15.8-69.7%), respectively, while in the 'VSD only' group, these values were 100%, 54.5 ± 10.6% (95% CI 32-72.3%) and 54.5 ± 10.6% (95% CI 30-72.3%), respectively. The only significant risk factor for recurrent MR ≥ 2+ during the follow-up period was mild residual MR in the early postoperative period (P = 0.037). CONCLUSIONS: In infants with VSD combined with MR, simultaneous MVR has no benefits simultaneous MVR provided no advantage over that of isolated VSD closure. We found that the presence of mild residual MR in the early postoperative period predisposes the development of MR ≥ 2+ in follow-up period.

Globular chitosan treatment of bovine jugular veins: evidence of anticalcification efficacy in the subcutaneous rat model.

Vascular xenografts are widely used in cardiovascular surgery as an alternative to autologous vessels and vascular allografts. Calcification is one of the main drawbacks of vascular grafts, especially among young patients and children. Among different anticalcification approaches, chitosan emerges as a highly promising candidate due to its versatility, natural origin, and biocompatibility. We investigated the anticalcification efficacy of globular chitosan ("Chitozol") as it demonstrated the improved rate of water solubility as compared with conventional linear macromolecules of chitosan. In addition, we supposed that compact globular form of "Chitozol" molecules could provide effective penetration of extracellular matrix of bovine jugular veins (BJVs). Our results revealed that "Chitozol" treatment mitigated calcification in the experimental groups as compared to the control groups (without any treatment, conventional treatment with glutaraldehyde, and commercially available Contegra conduit). Different concentrations of "Chitozol" (0.3% and 3%), as well as different incubation times (15 and 30min), were equally effective in the prevention of calcification. In addition, "Chitozol" treatment with decellularization of BJVs demonstrated slightly improved stress-strain properties of unimplanted samples. Thus, the filling of fresh BJV with globular chitosan is proposed as a promising emerging treatment for the mitigation of calcific degeneration in BJVs xenografts.

Concomitant ablation for atrial fibrillation during septal myectomy in patients with hypertrophic obstructive cardiomyopathy.

OBJECTIVE: The appearance of atrial fibrillation is associated with significant clinical deterioration in patients with obstructive hypertrophic cardiomyopathy; therefore, maintenance of sinus rhythm is desirable. Guidelines and most articles have reported the results of catheter ablation and pharmacologic atrial fibrillation treatment; nevertheless, data regarding concomitant procedures during septal myectomy are limited. The aim of this study was to assess the outcomes of concomitant atrial fibrillation treatment in patients with obstructive hypertrophic cardiomyopathy. METHODS: Between 2010 and 2013 in our clinic, 187 patients with obstructive hypertrophic cardiomyopathy underwent extended myectomy. In 45 cases, concomitant Cox-Maze IV procedure was performed; however, obstructive hypertrophic cardiomyopathy was the primary indication for surgery. Atrial fibrillation was paroxysmal in 26 patients (58%) and nonparoxysmal in 19 patients (42%). The mean age of patients was 52.8 ± 14.2 years (range, 22-74 years). Mean peak gradient was 90.7 ± 24.2 mm Hg, and interventricular septum thickness was 26.1 ± 4.3 mm. Mean atrial fibrillation duration was 17.3 ± 8.5 months. RESULTS: There were no early deaths. No procedure-related complications occurred with regard to ablation procedure. Complete atrioventricular block was achieved in 2 patients (4.0%). Mean crossclamping time was 61 ± 36 minutes. Peak left ventricular outflow tract gradient was 12.6 ± 5.5 mm Hg based on transesophageal echocardiography. The Maze IV procedure was used for ablation in all patients (radiofrequency ablation with bipolar clamp + cryolesion for mitral and tricuspid lines). Because of the atrial wall thickness (5-6 mm), applications were performed 8 to 10 times on each line. There were no cases of pacemaker implantation due to sinus node dysfunction. All patients were discharged in stable sinus rhythm. Mean follow-up was 23.7 ± 1.3 months. The rate of atrial fibrillation freedom was 100% (45 patients) at 6 months, 89% (40 patients) at 1 year, and 78% (35 patients) at 24 months. CONCLUSIONS: Concomitant ablation atrial fibrillation during septal myectomy in patients with obstructive hypertrophic cardiomyopathy is a safe and effective procedure and should be considered carefully in this patient group.

Risk Factors For Unfavorable Outcomes After Bidirectional Cavopulmonary Anastomosis.

BACKGROUND: Bidirectional cavopulmonary anastomosis (BCPA) is an important preliminary step toward the Fontan procedure; thus, understanding of risk factors for morbidity and mortality after BCPA may ultimately promote improved rates of success with Fontan completion and general survival. This study evaluated survival and predictors of unfavorable outcomes in patients after BCPA. METHODS: Clinical data of 157 patients who underwent BCPA from 2003 to 2015 at a single center were retrospectively analyzed. RESULTS: Three-year and nine-year survival after BCPA were 87.1% ± 2.8% and 85.8% ± 2.9%, respectively. Freedom from unfavorable outcomes (mortality, BCPA takedown, nonsuitability for Fontan procedure) was 83.8% ± 3.1% at three years and 73.5% ± 4.8% at nine years. Multivariate proportional hazards regression analysis revealed that total anomalous pulmonary venous connection (TAPVC; hazard ratio [HR]: 3.74, 95% confidence interval [CI]: 1.35-10.36; P = .01) and increased mean pressure in BCPA circuit (HR: 1.17, 95% CI: 1.02-1.34; P = .03) were independent risk factors for unfavorable outcomes. Postoperative mean pressure in BCPA circuit in patients with poor outcomes was median 16 mm Hg (interquartile range [IQR]: 14-18 mm Hg) versus median 14 mm Hg (IQR: 12-15.5 mm Hg) in patients with favorable outcomes ( P < .01). Preoperative (HR: 1.87, 95% CI: 1.20-2.91; P < .01) and postoperative atrioventricular valve regurgitation (AVVR; HR: 2.22, 95% CI: 1.24-3.94; P < .01) were also associated with unfavorable outcome in univariate Cox regression. CONCLUSIONS: Elevated mean pressure in the BCPA circuit is the main predictor of unfavorable outcome; therefore, thorough preoperative examination and careful patient selection are critical points for successful intermediate-stage and later Fontan completion. Total anomalous pulmonary venous connection and insufficient correction of AVVR worsen the prognosis in this patient group.

Bidirectional cavopulmonary anastomosis with additional pulmonary blood flow: good or bad pre-Fontan strategy.

Objectives: This study aimed to evaluate the influence of preserved additional pulmonary blood flow (APBF) on survival after bidirectional cavopulmonary shunt (BCPS) and completion of Fontan circulation. Methods: From March 2003 and April 2015, 156 patients with a single ventricle underwent BCPS. After performing propensity score analysis (1:1) for the entire sample, 50 patients with APBF (APBF group) were matched with 50 patients without APBF (no-APBF group). Results: Age ( P = 0.90), sex ( P = 0.57), weight ( P = 0.75), single ventricle morphology ( P = 0.87), type of neonatal palliative procedure ( P = 0.52), saturation ( P = 0.35), ejection fraction ( P = 0.90), Nakata index ( P = 0.70) and mean pulmonary artery pressure ( P = 0.72) were not significantly different between the groups. No significant survival difference was demonstrated ( P = 0.54). One and 4-year survival rates were both 89.1% ± 4.6% in the APBF group and 87.2% ± 4.9% and 83.4% ± 5.9%, respectively, in the no-APBF group. There was no significant difference in rates of Fontan completion ( P = 0.24), which was achieved in 22 patients from the APBF group (55.0%) and 26 patients from the no-APBF group (65.0%). However, Fontan completion occurred significantly earlier in the no-APBF group ( P < 0.01). In this group, Fontan procedure was performed before 36 months of inter-stage period in 45.9% ± 8.5% of cases (95% CI 31.0-63.7%) compared to only 13.3 ± 5.6% (95% CI 5.8-29.1%) in the APBF group. Conclusions: Our study demonstrates that APBF does not affect survival after BCPS or Fontan completion rate. APBF allows postponing the Fontan procedure without a negative effect on clinical status.

Human Induced Pluripotent Stem Cell-Derived Cardiomyocytes Afford New Opportunities in Inherited Cardiovascular Disease Modeling.

Fundamental studies of molecular and cellular mechanisms of cardiovascular disease pathogenesis are required to create more effective and safer methods of their therapy. The studies can be carried out only when model systems that fully recapitulate pathological phenotype seen in patients are used. Application of laboratory animals for cardiovascular disease modeling is limited because of physiological differences with humans. Since discovery of induced pluripotency generating induced pluripotent stem cells has become a breakthrough technology in human disease modeling. In this review, we discuss a progress that has been made in modeling inherited arrhythmias and cardiomyopathies, studying molecular mechanisms of the diseases, and searching for and testing drug compounds using patient-specific induced pluripotent stem cell-derived cardiomyocytes.

Transcriptome Characteristics and X-Chromosome Inactivation Status in Cultured Rat Pluripotent Stem Cells.

Rat pluripotent stem cells, embryonic stem cells (ESCs), and induced pluripotent stem cells (iPSCs) as mouse and human ones have a great potential for studying mammalian early development, disease modeling, and evaluation of regenerative medicine approaches. However, data on pluripotency realization and self-renewal maintenance in rat cells are still very limited, and differentiation protocols of rat ESCs (rESCs) and iPSCs to study development and obtain specific cell types for biomedical applications are poorly developed. In this study, the RNA-Seq technique was first used for detailed transcriptome characterization in rat pluripotent cells. The rESC and iPSC transcriptomes demonstrated a high similarity and were significantly different from those in differentiated cells. Additionally, we have shown that reprogramming of rat somatic cells to a pluripotent state was accompanied by X-chromosome reactivation. There were two active X chromosomes in XX rESCs and iPSCs, which is one of the key attributes of the pluripotent state. Differentiation of both rESCs and iPSCs led to X-chromosome inactivation (XCI). The dynamics of XCI in differentiating rat cells was very similar to that in mice. Two types of facultative heterochromatin described in various mammalian species were revealed on the rat inactive X chromosome. To explore XCI dynamics, we established a new monolayer differentiation protocol for rESCs and iPSCs that may be applied to study different biological processes and optimized for directed derivation of specific cell types.

Randomized trial of fish oil infusion to prevent atrial fibrillation after cardiac surgery: data from an implantable continuous cardiac monitor.

OBJECTIVE: To test the hypothesis that perioperative OMEGA-3 polyunsaturated fatty acid infusion would reduce the incidence of postoperative atrial fibrillation in patients after coronary artery bypass grafting as assessed by an implantable continuous cardiac monitor. DESIGN: Prospective, randomized, double-blind, placebo-controlled study. SETTING: Tertiary cardiothoracic referral center. PARTICIPANTS: Thirty-nine patients with coronary artery disease who underwent surgery with cardiopulmonary bypass. INTERVENTIONS: Patients were assigned randomly to receive either OMEGA-3 polyunsaturated fatty acids (200 mg/kg/day starting before anesthesia induction for 24 hours followed by 100 mg/kg/day for 7 days) or placebo. The primary outcome was freedom from atrial fibrillation at 2-year follow-up. Reveal(®) cardiac monitor was implanted subcutaneously in all patients. Data from the cardiac monitor were collected on the 10th day and 3, 6, 12, and 24 months postoperatively. MEASUREMENT AND MAIN RESULTS: Postoperative atrial fibrillation developed in 4 (19%) patients in the control group and in 5 (27.8%) patients in the study group at 10-day follow-up (p = 0.88). At 2-year follow-up, 5 (27.8%) patients in the control group and 6 (35.3%) patients in the study group had atrial fibrillation (p = 0.9). Atrial fibrillation duration predicted risk of cardiovascular hospitalization at the 2-year follow-up (regression coefficient estimate = 0.24, standard error 0.02, p<0.0001; R(2) = 0.74). CONCLUSIONS: Infusion of OMEGA-3 polyunsaturated fatty acids failed to prevent the occurrence of atrial fibrillation in 2 years after coronary artery bypass grafting surgery. The cumulative atrial fibrillation duration registered by the continuous cardiac monitor at the 2-year follow-up was a significant predictor of an adverse outcome.