Cardiopulmonary Bypass Support Research Articles

Successful Resuscitation of Porcine Hearts After 12 and 24 h of Static Cold Storage With Normothermic Ex Situ Perfusion.

Heart transplantation is always an emergency because the transplant needs to occur within 6 h after procurement to prevent primary graft dysfunction. Static cold storage (SCS) is the gold-standard preservation method. This study describes the outcomes of hearts preserved after prolonged SCS (12 and 24 h); those are then resuscitated with a novel normothermic ex situ heart perfusion (NEHP) system. Anesthetized piglets (n = 10) were used as heart donors. Hearts were procured and stored at 5 °C CoStorSol following standard SCS protocols. Two groups were studied: SCS-12 h and SCS-24 h. After SCS, 8 h of NEHP (37 °C blood-based perfusate) was performed at 0.7-1.0 mL/min/g of cardiac tissue. NEHP parameters were monitored continuously. Results were corroborated with 3 additional hearts transplanted orthotopically in healthy recipients (n = 3) after SCS (24 h) + NEHP (5 h). Recipients were observed for 90 min after weaning off cardiopulmonary bypass support. All hearts (after 12 and 24 h of SCS) regained normal function and metabolism within 10 min and retained it throughout 8 h of NEHP. No differences were observed in NEHP parameters and histopathology between groups. Three hearts were successfully transplanted after a total ~30 h of preservation (24 h of SCS + 5 h of NEHP + 1 h of second cold ischemia time). The 3 recipients were weaned off cardiopulmonary bypass with mild vasopressor support. NEHP has the potential to routinely resuscitate porcine hearts that have undergone SCS for up to 24 h, restoring them to viable function. By objectively assessing heart function before transplant, NEHP may enhance the success rate of transplants. If these resuscitated hearts can be successfully transplanted, it would support the effectiveness of NEHP in ensuring heart viability.

Thoracoabdominal Normothermic Regional Perfusion Using Mobile Closed Extracorporeal Circuit in Circulatory Death Determination Heart Donors.

Thoracoabdominal normothermic regional perfusion (TA-NRP) is increasingly implemented in donation after circulatory determination of death (DCD). Thoracoabdominal normothermic regional perfusion allows thoracic and abdominal organs to be perfused with warm, oxygenated blood after declaration of death, interrupting ischemia. Evidence is accumulating supporting the use of TA-NRP to improve the outcome of grafts from DCD donors. Thoracoabdominal normothermic regional perfusion may restore and maintain a near-physiological environment during procurement. Moreover, during TA-NRP it is feasible to evaluate the heart in situ. Thoracoabdominal normothermic regional perfusion could be performed through different cannulation techniques, central or peripheral, and, with different extracorporeal circuits. The use of conventional cardiopulmonary bypass and extracorporeal life support (ECLS) devices equipped with open circuits has been described. We report the use of a fully mobile, closed ECLS circuit to implement TA-NRP. The procedure was successfully performed in a peripheral center without a cardiac surgery program through a percutaneous cannulation approach. This strategy resulted in combined heart, liver, and kidney recovery despite a significantly prolonged functional warm ischemia time. The feasibility of TA-NRP using modified but still closed fully mobile ECLS circuits could furtherly support the expansion of DCD programs, increasing the availability of heart for transplantation, and the quality of the grafts, improving recipients' outcome.

A clinical comparison of glycol and water-based heater-cooler systems for cardiopulmonary bypass.

While newer heater-cooler technologies using ethylene glycol-based (GB) solutions during cardiothoracic surgery have become commercially available, there is a paucity of clinical data describing their effectiveness during cardiopulmonary bypass (CPB) support. This analysis aimed to compare clinical characteristics and procedural outcomes using water-based (WB) and GB heater-cooler systems. A retrospective analysis was performed on consecutive adult patients undergoing CPB from June to October 2022 comparing WB or GB groups. The primary outcome was a composite of operative death or major morbidity. Secondary endpoints included transfusion requirements on CPB, patient cooling and warming rates, and vasoactive-inotropic scores (VIS) at case completion. P-control charts were used to monitor the weekly incidence of the composite outcome. A sub-analysis was performed to evaluate the primary outcome for cardiac surgery cases indexed by the Society of Thoracic Surgeons (STS). There were 167 patients included for analysis; 87 (52.1%) underwent CPB with a WB system and 80 (47.9%) with a GB system. GB procedure subjects were younger (p = .01), experienced longer CPB times (p = .034), and were more likely to receive thoracic transplant or aortic surgery (p = 0.015). The composite outcome of operative mortality or major morbidity occurred in 29.9% and 24% of the WB and GB groups, respectively (p = .372). P-control charts indicated a weekly mean incidence of 30% during WB practice, which decreased to 24% with GB practice. Among 106 STS-indexed cardiac surgery cases, mean composite outcome incidence decreased from 19% to 6% following our GB transition. Additionally, cooling, and warming rates indexed to patient BSA and VIS at case completion were not significantly different. Our analysis demonstrated a safe transition from WB to GB heater-cooler technologies in our practice. This early analysis suggests that GB heater coolers may be safely adopted to mitigate the risks of nontuberculous mycobacterium infections for cardiac surgical patients.

Pediatric continuous-flow total artificial heart with rotor axial position tracking technology: First report of in vivo assessment

BackgroundThe pediatric continuous-flow total artificial heart (P-CFTAH) is a novel double-ended centrifugal pump designed with the intent to provide circulatory support for pediatric heart failure. ObjectivesTo enable continuous monitoring of pump hemodynamics, Hall effect sensors (HES) were embedded inside the P-CFTAH design to track both axial movement and position of the pump rotor post-implantation. Herein, we report an early in vivo evaluation of the P-CFTAH with HES, implanted in small-sized ovine models. MethodsFive healthy lambs were used for the P-CFTAH implantation via a full median sternotomy and cardiopulmonary bypass support. Successful evaluation of the P-CFTAH was achieved in four out of five (n = 4, 20.9 ± 1.3 kg). The hemodynamics and operating conditions were continuously recorded with varying pump speeds (2,800-5,000 rpm), systemic/pulmonary vascular resistance ratio, and high- and low-volume conditions. Among the four cases, P-CFTAH with HES embedded in the rotor was used in two cases. ResultsAll surgical procedures were uneventful, and the optimal anatomical fit of the pump was shown in the chest. Differences between the left and right atrial pressures were mostly maintained within the intended limit of ± 10 mm Hg throughout the design range of systemic and pulmonary vascular resistance. The HES accurately traced the rotor position, showing a positive correlation with atrial pressure differences. ConclusionsThe findings suggest that the P-CFTAH has the potential to provide self-balancing circulatory support for pediatric heart failure patients. The study contributes to the development of a pediatric-sized total artificial heart with improved monitoring.

Perventricular device closure of the ventricular septal defects in children-first experience in the United Arab Emirates

BackgroundVentricular septal defect (VSD) is the most common congenital cardiac malformation, accounting for approximately 30% of congenital heart defects. Conventional surgical repair using cardiopulmonary bypass is invasive and associated with morbidities and prolonged hospital stay. With the advent of interventional approaches and availability of different occluding devices, the technique of perventricular device closure is evolving and being implemented successfully in larger groups of patients. We present herein, our initial experience of perventricular device closure for the ventricular septal defects in children to assess risks and benefits.MethodsFrom March, 2023 to February, 2024, we have performed perventricular closure of ventricular septal defects in 13 children, under guidance of transesophageal echocardiography without cardiopulmonary bypass support. The median age at operation was 2 year (range 1.3–10 years) with the median body weight 11 kg (range 8.7–16.6 kg). Sixty-nine percent were males. The ventricular septal defect sizes ranged from 2.7 to 6 mm (mean 4.7 mm). Seven defects were perimembranous, four sub-aortic and two were muscular. One patient also underwent pulmonary artery de-banding with pulmonary artery balloon angioplasty and other one patent ductus arteriosus ligation, concomitantly. For defect closure, we used ventricular septal defect occlusion device (MemoPart™, Lepu Medical Technology Company, China) through a 3-cm skin incision in the lower- third of the sternum. The device sizes ranged from 5 to 8 mm (mean 6.9+-1.8 mm) and all patients except for two required symmetrical devices.ResultsAll patients underwent device closure successfully. The procedural duration ranged between 32 and 52 min. None of the patients required cardiopulmonary bypass. The mean ventilation time and intensive care unit stay was 3 and 24 h, respectively. None of the patients required inotropic support or blood transfusions. Moreover, no patients developed any arrhythmias including heart block. The average length of hospital stay was 4.4 days. At the latest follow up, there were no residual shunts, conduction disturbances, device dislodgement or major aortic or tricuspid valve complications seen in any patients. There was no mortality.ConclusionsPerventricular device closure of ventricular septal defects is a less invasive, extremely safe and effective method in children. It is associated with very fast recovery, shorter hospitalization time and better cosmetic incision. Moreover, it avoids cardiopulmonary bypass. The modifications and refinements in the design, material and implantation techniques will help in expanding the indications and prevent complications in the long-term.

Perioperative use of Impella device in very high-risk coronary artery bypass grafting

ABSTRACT This case study presents a high-risk coronary artery bypass grafting (CABG) patient with a recent anterior wall myocardial infarction and severely impaired left ventricular function. The patient underwent on-pump CABG with prolonged cardiopulmonary bypass support. The management strategy used hybrid mechanical circulatory support, intra-aortic balloon pump, and Impella CP, improved postoperative recovery, and prevented low cardiac output syndrome development.

Prevalence and clinical implications of heightened plastic chemical exposure in pediatric patients undergoing cardiopulmonary bypass.

Phthalate chemicals are used to manufacture plastic medical products, including many components of cardiopulmonary bypass (CPB) circuits. We aimed to quantify iatrogenic phthalate exposure in pediatric patients undergoing cardiac surgery and examine the link between phthalate exposure and postoperative outcomes. The study included pediatric patients undergoing (n=122) unique cardiac surgeries at Children's National Hospital. For each patient, a single plasma sample was collected preoperatively and two additional samples were collected postoperatively upon return from the operating room and the morning after surgery. Concentrations of di(2-ethylhexyl) phthalate (DEHP) and its metabolites were quantified using ultra high-pressure liquid chromatography coupled to mass spectrometry. Patients were subdivided into three groups, according to surgical procedure: (1) cardiac surgery not requiring CPB support, (2) cardiac surgery requiring CPB with a crystalloid prime, and (3) cardiac surgery requiring CPB with red blood cells (RBCs) to prime the circuit. Phthalate metabolites were detected in all patients, and postoperative phthalate levels were highest in patients undergoing CPB with an RBC-based prime. Age-matched (<1 year) CPB patients with elevated phthalate exposure were more likely to experience postoperative complications. RBC washing was an effective strategy to reduce phthalate levels in CPB prime. Pediatric cardiac surgery patients are exposed to phthalate chemicals from plastic medical products, and the degree of exposure increases in the context of CPB with an RBC-based prime. Additional studies are warranted to measure the direct effect of phthalates on patient health outcomes and investigate mitigation strategies to reduce exposure.

Robotic-enhanced hybrid ablation for persistent and long-standing atrial fibrillation: Early assessment of feasibility, safety, and efficacy

ObjectivesTo assess feasibility, safety, and early efficacy of robotic-enhanced epicardial ablation (RE-EA) as first stage of a hybrid approach to patients with persistent (PsAF) and long-standing atrial fibrillation (LSAF). MethodsSingle-center, retrospective analysis of patients with documented PsAF and LSAF who underwent RE-EA followed by catheter-guided endocardial ablation. Postoperatively, patients were monitored for major adverse events and underwent rhythm follow-up at 3 and 12 months. ResultsBetween January 2021 and June 2023, we performed RE-EA in 64 patients (73.5% male, CHA2DS2-VASc 2.7 ± 1.6, BMI 34.1 ± 6.3 kg/m2). Mean AF preoperative duration and left atrial volume index were, respectively, 85 months and 47.5 mL/m2. Through the robotic approach, the intended lesion set was completed in all patients without cardiopulmonary bypass support, conversion to thoracotomy/sternotomy, blood transfusions, or perioperative mortality. The average LOS was 1.7 days, with only 1 patient requiring intensive care unit admission and >65% of patients discharged within 24 hours. At follow-up, 2 (3.1%) patients experienced new left pleural effusion or hemidiaphragm paralysis requiring treatment. There were no readmissions related to AF, stroke, thromboembolic events, or deaths. The mean interval between the epicardial and endocardial stages of the procedure was 5.9 months. Rhythm follow-up showed AF resolution in 73.4% and 71.9% of patients at 3 and 12 months, respectively. ConclusionsRE-EA is a feasible and safe, first-stage approach for the treatment of patients with PsAF and LSAF. It improves exposure of the intended targets, favors short hospital stay, and facilitates return to activity with satisfactory AF treatment in the short term.

Coral reef aorta: a rare form of obstruction of the ascending aorta in adolescent with aortopathy- case report

BackgroundSupra aortic obstruction in children is uncommon and is seen in certain unique conditions. While intraluminal obstruction due to heavy calcification is seen in older populations, it is not described in pediatric populations. The coral reef aorta is a rare and distinct calcifying disease causing luminal obstruction of the suprarenal aorta in adults. The definition of this diagnosis relies entirely on the unique aspects and consistency of the lesions, which are rock-hard, irregular, gritty plaques with a white luminal surface resembling a coral reef. However, no such case has been described in children.Case presentationWe present an adolescent boy who presented with a heavily calcified ascending aortic lesion associated with aortopathy and hypertension, 12 years after an aortic coarctation repair. The investigations included echocardiography, magnetic resonance and computer-tomographic imaging. A 3-D model was printed in order to visualize and plan surgical steps in advance for safe placement of clamps and defining the extent of resection. In addition, it provided an idea about tissue quality, thickness, spatial relationship, and orientation in relation to surrounding structures. Successful resection and replacement of the diseased segment of the aorta were achieved on cardiopulmonary bypass support. Post-operative recovery was uneventful, and at 6-month follow-up, the patient is doing well. In this report, various aspects of such lesions have been discussed, including clinical presentations, complications, planning and conduct of a safe cardiopulmonary bypass, and precautions during surgery for a successful outcome.ConclusionComplicated obstructive aortic lesions in children require careful assessment, appropriate advanced imaging, and the use of 3-D printing technology in order to plan and perform safe and effective surgical management. The etiology of severe calcified aorta in children may be related to metabolic factors, previous surgery, use of a homograft, or an inflammatory process. However, it has yet to be proven.

Mini-access ascending aorto-bifemoral bypass surgery for the treatment of aortic steno-occlusive disease

ObjectivesMid-aortic syndrome is a rare condition characterized by severe aortic narrowing, leading to high upper body blood pressure and organ hypoperfusion, necessitating surgical intervention. Although central bypassing is considered ideal, it involves extensive incisions. To overcome these limitations, less-invasive approaches have been developed. This study aims to introduce a mini-access approach using video-endoscopy and to evaluate the feasibility and outcomes of mini-access ascending aorto-bifemoral bypass surgery. MethodsFrom November 2020 to May 2022, we performed ascending aorta to bifemoral artery bypass operations on 7 patients to treat steno-occlusive diseases in the downstream aorta. A Y-graft was created, and procedures were conducted under general anesthesia using video-endoscopy with limited skin incisions. ResultsIntraoperatively, there were no major complications, and none of the patients required cardiopulmonary bypass support. Furthermore, there were no postoperative mortalities or major complications. Postoperatively, the mean ankle-brachial index significantly improved from 0.59/0.59 to 0.96/0.92 (P = .004), and the mean glomerular filtration rate increased from 61.1 to 85.3 mL/min/1.73 mm2 (P = .012). Additionally, symptoms of claudication resolved in all patients. ConclusionsVideoscope-assisted mini-access aortic bypass surgery not only provides favorable early postoperative outcomes but also represents a technically feasible alternative to traditional surgical approaches for the treatment of steno-occlusive aortic diseases.

On Pump Beating Heart Coronary Artery Surgery in Patients Requiring Urgent Revascularization.

When acute coronary syndrome patients necessitate immediate revascularization, heart-on-pump coronary artery bypass grafting may be regarded as a viable substitute for conventional on-pump surgery. Our clinical experience and initial outcomes of heart-on-pump coronary surgery in patients with acute coronary syndrome are detailed in this article. This research endeavor was a retrospective analysis that spanned the years March 2011 to August 2023. The sample size comprised 2816 patients who had undergone coronary artery surgery. During this period, the same surgical team performed coronary artery bypass surgery on 411 of these patients, who underwent beating heart surgery while on cardiopulmonary bypass support and without cardioplegic arrest; this was done under emergency conditions. 9.3 ± 2.2 hours elapsed between the initiation of acute myocardial infarction and the commencement of coronary artery bypass grafting (CABG). A mean of 4.0 grafts was applied (2.2 ± 1.1). Mortality in hospitals was calculated for sixteen patients. Following surgery, twenty-six patients developed an inadequate cardiac output syndrome. Despite having renal dysfunction, none of the eight individuals needed hemodialysis. The mean duration of stay in intensive care was 3.2 (2.2 ± 1.1) days, while the mean length of hospitalization was 9.2 (4.3 ± 2.4) days. We believe that for high-risk patients with multivascular coronary artery disease who require an emergency coronary artery bypass graft, on-pump beating heart revascularization could be a viable option.

Abstract 13838: Hemostatic Disorder During Left Ventricular Assist Device Implantation in Swine

Introduction: Implantation of left ventricular assist devices (LVAD) conventionally requires the use of cardiopulmonary bypass (CPB). Among others, mechanical circulatory support devices favor intraoperative hemostatic disorder. Hypothesis: Despite the high risk of severe bleeding and thromboembolic complications, little is known about the intraoperative extent of hemostatic disorder during LVAD implantation.This study aimed to determine the extent of hemostatic disorder during LVAD implantation in a porcine model under CPB and LVAD support, separately. Methods: We performed LVAD implantation in 10 female German Landrace pigs (body weight 104 ± 13 kg). Blood samples were collected three times: at (1) Baseline, (2) after CPB and (3) after LVAD. For CPB, cannulation of the left jugular vein and right femoral artery was performed. After sternotomy and pericardiotomy, apical coring was performed under CPB. A continuous-flow LVAD with transventricular outflow graft was implanted. For CPB and LVAD, a flow rate of 3-7 L/min and a rotational speed of 4000 to 7200 rpm were aimed, respectively. Hemostatic laboratory markers from all times were compared by Wilcoxon signed rank test. Results: Compared to Baseline, CPB led to a significant decrease of fibrinogen and antithrombin as well as an increase of von Willebrand factor (vWF) ratio and D dimer (DD). Compared to after CPB, there was a continued decrease of antithrombin and an increase of DD, as well as a significant increase of vWF and vWF activity under LVAD support. Conclusion: Among others, CPB and LVAD separately contribute to hemostatic disorder during LVAD implantation. Human laboratory markers allowed early detection of intraoperative hemostatic changes in pigs. Further studies are needed to investigate whether off-pump LVAD implantation reduces perioperative hemostatic disorder.

Outcomes and Direct Cost of Isolated Nonemergent CABG in Patients With Low Ejection Fraction.

Preoperative left ventricular ejection fraction (LVEF) is one of the main predictors of outcomes in cardiac surgery. We present current era outcomes and associated direct cost in nonemergent isolated coronary artery bypass surgery (CABG) patients with LVEF <20% over the past 6 years and compare it with higher EF subgroups. Six-year data from 2016 to 2022 at hospitals sharing Society of Thoracic Surgeons and financial data with Biome Analytics were analyzed based on 3 EF subgroups (EF ≤20%, EF 21% to 35%, and EF >35%). Outcomes and costs were assessed. Overall 30-day mortality of 12,649 patients was 1.9%. The EF ≤20% (n = 248), EF 21% to 35% (n = 1,408), and EF >35 (n = 10,993) cohorts had mortality of 6.9%, 3.7%, and 1.6%, respectively. The EF ≤20% subgroup had higher use of cardiopulmonary bypass, blood products, and mechanical support. In addition, the EF ≤20% subgroup had higher complication rates in almost all measured categories. Also, the EF ≤20% cohort had significantly higher length of stay, intensive care unit (ICU) hours, ICU and hospital readmissions, and lowest discharge to home rate. The strongest factors associated with mortality were postoperative cardiac arrest, renal failure requiring dialysis, extracorporeal membrane oxygenation, sepsis, prolonged ventilation, and gastrointestinal event. The overall median direct cost of care was $37,387.79 ($27,605.18, $51,720.96), with a median direct cost of care in the EF ≤20%, EF 21% to 35%, and EF >35% subgroups of $52,500.17 ($34,103.52, $80,806.79), $44,108.32 ($31,597.58, $63,788.03), and $36,521.80 ($27,168.91, $50,019.31), respectively. In nonemergent isolated CABG surgery, low EF continues to have higher surgical risks and higher direct cost of care despite advances in cardiovascular care.

Surgical Retrieval of an Embolized Patent Ductus Arteriosus Closure Device in an Infant Weighing 1050 G.

Pro00015566-07/01/2021-Children's National Medical Center.

The effects of pulsatile versus nonpulsatile flow on cerebral pulsatility index, mean flow velocity at the middle cerebral artery, regional cerebral oxygen saturation, cerebral gaseous microemboli counts, and short-term clinical outcomes in patients undergoing congenital heart surgery

ObjectiveThe objective of this retrospective review was to evaluate whether or not pulsatile flow improves cerebral hemodynamics and clinical outcomes in pediatric congenital cardiac surgery patients. MethodsThis retrospective study included 284 pediatric patients undergoing congenital cardiac surgery with cardiopulmonary bypass support utilizing nonpulsatile (n = 152) or pulsatile (n = 132) flow. Intraoperative cerebral gaseous microemboli counts, pulsatility index, and mean blood flow velocity at the right middle cerebral artery were assessed using transcranial Doppler ultrasound. Clinical outcomes were compared between groups. ResultsPatient demographics and cardiopulmonary bypass characteristics between groups were similar. Although the pulsatility index during aortic crossclamping was consistently higher in the pulsatile group (P < .05), a significant degree of pulsatility was also observed in the nonpulsatile group. No significant differences in mean cerebral blood flow velocity, regional cerebral oxygen saturation, or gaseous microemboli counts were observed between the perfusion modality groups. Clinical outcomes, including intubation duration, intensive care unit and hospital length of stay, and mortality within 180 days were similar between groups. ConclusionsAlthough the pulsatility index was greater in the pulsatile group, other measures of intraoperative cerebral perfusion and short-term outcomes were similar to the nonpulsatile group. These findings suggest that while pulsatile perfusion represents a safe modality for cardiopulmonary bypass support, its use may not translate into detectably superior clinical outcomes.

Treatment of long-segment congenital tracheal stenosis with congenital cardiovascular defects in infancy.

This study aims to evaluate the outcomes of simultaneous repair for infants with long-segment congenital tracheal stenosis (LSCTS) with congenital cardiovascular defects (CCD). We retrospectively reviewed the clinical data of infants aged less than 1 year with LSCTS and CCD who underwent simultaneous repair at Children's Hospital of Chongqing Medical University from January 2020 to March 2023. A systematic search of PubMed, Embase, and Cochrane Library for the relevant published studies that reported the simultaneous repair of CTS and CCD in infancy was conducted in March 2023. The inverse variance method of DerSimonian-Laird (D+L) was used for estimate synthesis. A total of thirteen infants with a mean age of 5.6±3.1 months and a mean weight of 6.4±0.9Kg underwent slide tracheoplasty with modified procedures and cardiovascular operations. LSCTS was diagnosed in all thirteen patients. Nine infants were ventilator dependent, and four patients were operated on due to persistent wheezing and recurrent respiratory infections. Seven patients underwent pulmonary artery sling repair, and six underwent atrial septal defect repair. All infants were repaired utilizing cardiopulmonary bypass (CPB) support. Significant complications were recorded in three patients. In-hospital deaths were seen in one case. The median tracheal minimum diameter of hospital survivors was significantly larger than the preoperative minimum diameter (p<0.001). The mean follow-up duration was 17.1±7.1 months. There was no late mortality during the follow-up. Twelve studies were included based on our search strategy. The pooled estimate of mortality in the literature was 10.9% (95%CI, 5.3%-17.7%, I2=0). The pooled estimate of airway re-interventions was 28.8% (95%CI, 14.5%-43.2%, I2=74%). Simultaneous repair of LSCTS and CCD in infancy is safe and effective. Slide tracheoplasty with appropriate technical modifications may be valid for LSCTS repair without significant restenosis and reinterventions.

Giant myxoma of the right sections of the heart obstructing the inferior vena cava: A case report

Objective: We present a rare case of surgical management of giant myxoma of the right heart with obstruction of the orifice of the inferior vena cava (IVC), obstruction of the right atrioventricular orifice, with the development of high pulmonary hypertension, and severe heart failure. Case presentation: A 39 years old male patients applied to the consultative polyclinic with typical complaints of severe shortness of breath, palpitations, severe weakness, almost bed rest, severe swelling of the lower extremities, with a transition to the anterior abdominal wall (edema). On physical examination signs of severe heart failure NYHA class IV were revealed. Imaging demonstrated giant right atrial myxoma obstructing IVC with base originated in fossa ovalis, obstructing tricuspid valve and protruding in the right ventricle occupying 50% of its cavity. The surgical removal of the giant RA myxoma protruding the right ventricle and obstructing IVC and tricuspid valve was performed under cardiopulmonary bypass and hemodynamic support. The patient was discharged on the 10th day after surgery and only residual minimal tricuspid regurgitation was revealed on follow-up examination. Conclusion: The described case from our practice proves the possibility of a severe course of giant myxomas of the right heart, with the development of deep hemodynamic complications of systemic and pulmonary circulation. The chosen correct tactics of surgical treatment provided a favorable result, despite the severity of the initial condition and the degree of hemodynamic disturbance. Intraoperative tactics and technique for performing the stages of urgent surgery were chosen based on the situation, the features of the anatomical structure of the tumor, and the severe complications that arose. Our case proves the possibility of adequate implementation of such interventions, when choosing the right tactics of surgical treatment. Take home message: If clinical signs of circulatory failure, heart failure are detected, it is necessary to perform echocardiography. If mass formations of the heart chambers are detected, immediately refer the patient to specialized cardiac surgery clinics to resolve the issue of surgical correction of pathology.

Ortalama trombosit hacmi ve trombosit dağılım genişliğinin off-pump koroner baypas greftleme ameliyatlarındaki değişimi ve bu değişimin ameliyat sonrası kanama miktarı ile ilişkisinin araştırılması

Objectives: This study aimed to examine the relationship between preoperative mean platelet volume (MPV) and platelet distribution width (PDW) values and postoperative drainage amounts in coronary artery bypass grafting operations without cardiopulmonary bypass support. Patients and methods: One hundred three patients (78 males, 25 females; mean age: 62.8±10.0 years; range, 40 to 85 years) who underwent off-pump coronary artery bypass grafting surgery between December 2015 and May 2018 were included in the retrospective study. Results: There was a negative and insignificant relationship between preoperative MPV values and postoperative drainage (p=0.223, r=-0.121). There was a positive and insignificant relationship between preoperative PDW values and postoperative drainage (p=0.167, r=0.137). Conclusion: According to the results of our study, PDW and MPV values did not correlate with postoperative bleeding in patients who underwent off-pump coronary artery bypass grafting.

BIO6: Acute In Vivo Studies of the Left Atrial Assist Device and Simulated Diastolic Heart Failure

Purpose: The Left Atrial Assist Device (LAAD) is a mixed-flow pump in development for patients who have diastolic heart failure (DHF). The device is implantable in the mitral plane and delivers blood from the left atrium to the left ventricle to mitigate high left atrial pressure. The purpose of this study was to assess the operational in vivo performance of the LAAD with simulated DHF conditions. Methods: The LAAD was implanted in calves (n=8; mean weight 84.5 kg) using cardiopulmonary bypass (CPB) support through a left atrial incision. Various pump-operating conditions, including mean pump speeds ranging from 3,600 to 5,200 rpm and three DHF conditions with a balloon (0, 50 and 70 mL) inflated inside the left ventricle, were tested and evaluated. The hemodynamics for each pump setting were recorded. As for the DHF conditions, the effect of the balloon inflation was evaluated before and after the LAAD implantation in 5 cases (mean weight 89.1 kg) among the 8 calves. Results: The LAAD responded to all control inputs and ran as expected during the experiment. Anatomical fit of the LAAD was suitable for all hearts, but some suction events were occasionally observed at speeds over 4,400 rpm, mainly due to of the small size of the normal left atrium. For the simulated DHF conditions, the baseline data (without LAAD) showed lower cardiac output and aortic pressure (Fig 1A and 1B) and higher LAP and left ventricle end diastolic pressure (Fig 1C and 1D) as the DHF conditions increased in severity. The LAAD seemed to mitigate the severity of the simulated DHF hemodynamics (Fig 1A-D). Conclusion: The acute implantations of the LAADs in calves were successful, and the pump showed improvement of the hemodynamics in the simulated DHF conditions. Additional studies, including chronic evaluations are underway.Figure 1. The in vivo hemodynamics changes under 50 and 70 mL of balloon inflation compared with no balloon inflation. A: Cardiac output (CO), B: Arterial pressure (AoP), C: Left atrial pressure (LAP), and D: Left ventricular end-diastolic pressure (LVEDP).

Association of postoperative atrial fibrillation with higher dosing ratios of protamine-to-heparin.

Background: Postoperative atrial fibrillation (POAF) is defined as new-onset AF in the immediate postoperative period. The relatively high incidence of POAF after cardiac surgery is well described, but pathophysiological mechanisms underlying the initiation, maintenance, and progression of POAF may be multifactorial and have not yet been comprehensively characterized. One of the mechanisms includes altered Ca2+ kinetics. Accumulating evidence has suggested that altered atrial cytosolic calcium handling contributes to the development of POAF, protamine reversibly modulates the calcium release channel/ryanodine receptor 2 (RyR2) and voltage-dependent cardiac RyR2. However, it is currently unknown whether such abnormalities contribute to the arrhythmogenic substrate predisposing patients to the development of POAF. Methods: We have retrospectively analyzed 147 patients who underwent cardiac surgery with cardiopulmonary bypass support. Of these, 40 patients were excluded from the analysis because of pre-existing AF. All patients received heparin followed by protamine at different dosing ratios of protamine-to-heparin, depending on the periods studied. Results: The dosing ratio of protamine-to-heparin=1.0 was compared with higher dosing ratios of protamine-to-heparin >1.0 up to 1.7. POAF developed in 15 patients (15/107=14%), of these, 5 out of 57 patients (33.3%) in the dosing ratio of protamine-to-heparin=1.0 and 10 out of 35 patients (66.7%) in the higher dosing ratios of protamine-to-heparin. Statistical significance was observed in patients with higher dosing ratios of protamine-to-heparin, compared with the dosing ratio of protamine-to-heparin=1.0 (odds ratio=3.890, 95% CI=1.130-13.300, p-value=0.031). When types of diseases were analyzed in terms of higher dosing ratios of protamine-to-heparin, only valvular disorders were significantly associated with POAF (p=0.04). Conclusions: Protamine is clinically utilized to reverse heparin overdose and has been shown to display immunological and inflammatory alterations. However, its association with POAF has not been reported. Our results provide evidence that higher dosing ratios of protamine-to-heparin may increase the incidence of POAF.