Toward More Granular Guidelines in AAOCA: Associating Anatomical Details With Specific Surgical Strategies.

Patients with anomalous aortic origin of a coronary artery (AAOCA) require imaging to clarify the multiple potential anatomic sites of obstruction (fixed or dynamic). Once repaired, the pathway of blood to the myocardium must not encounter: (1) intrinsic ostial stenosis, (2) obstruction from compression or distortion near the commissure or the intercoronary pillar, (3) stenosis where the artery exits the aortic wall (due to an acutely angled "take-off"), (4) compression due to a pathway between the great vessels, (5) stenosis or compression along an intramural course, or (6) compression due to an intramuscular (intraseptal/intraconal) course. Detailed anatomic evaluation of each of these locations allows the surgeon to select an appropriate repair strategy, and each of these abnormal anatomic features should be "matched" with a particular surgical correction. We speculate that the most common surgical repair, unroofing with or without tacking, is often inadequate, as in isolation, it may not allow for correction with a large orifice from the appropriate sinus, without an interarterial course. While the evidence base is insufficient to call these recommendations formal guidelines, these recommendations should serve as a basis for further validity testing, and ultimate evolution to more granular guidelines on AAOCA management.

Passive high-frequency microrheology of blood.

Indicative of various pathologies, blood properties are under intense scrutiny. The hemorheological characteristics are traditionally gauged by bulk, low-frequency indicators that average out critical information about the complex, multi-scale, and multi-component structure. In particular, one cannot discriminate between the erythrocytes contribution to global rheology and the impact of plasma. Nevertheless, in their fast stochastic movement, before they encounter each other, the erythrocytes probe the subtle viscoelasticity of their protein-rich environment. Thus, if these short time scales can be resolved experimentally, the plasma properties could be determined without having to separate the blood components; the blood is practically testing itself. This microrheological description of blood plasma provides a direct link between the composition of whole blood and its coagulability status. We present a parametric model for the viscoelasticity of plasma, which is probed by the erythrocytes over frequency ranges of kilohertz in a picoliter-sized volume. The model is validated both in vitro, using artificial hemo-systems where the composition is controlled, as well as on whole blood where continuous measurements provide real-time information. We also discuss the possibility of using this passive microrheology as an in vivo assay for clinically relevant situations where the blood clotting condition must be observed and managed continuously for diagnosis or during therapeutic procedures at different stages of hemostatic and thrombotic processes.

Joint programmes in paediatric cardiac surgery: an update and descriptive analysis.

OBJECTIVE: Joint programmes are an alternative model that may aid in improving congenital cardiac surgery outcomes while avoiding the potential resource and accessibility challenges that could result from regionalisation. This study aims to characterise current joint programmes, identify factors that are associated with joint programme success and failure, and gauge attitudes within the profession regarding joint programmes as an alternative. METHODS: A multiple choice survey with 23 standard questions for all programmes and additional 42 additional questions for each participant hospital in a joint programme was addressed to paediatric cardiac surgeons in the United States of America. Questions were designed to qualitatively and quantitatively characterise congenital cardiac surgery joint programmes. RESULTS: Of the 34 unique congenital cardiac surgery programmes identified in this survey, 14 have participated in a joint programme and 50% of those joint programmes existed for more than 10 years. Most joint programmes (86%) participate or participated in a model where the hospital participants are engaged in a "mother-daughter" relationship in both perception and case volume distribution. In three out of four defunct joint programmes, there were case complexity limitations placed on partner institutions, but the now independent partner institutions operate with no limitation on complexity. Most (71%) hospital participants in a joint programme felt that the joint programme produced better outcomes than two separate programmes; however, among those who participate or have participated in a joint programme, only 18% felt that joint programmes were the optimal model for delivery of congenital cardiac surgical care.

Computational Fluid Dynamics Study of Cerebral Thromboembolism Risk in Ventricular Assist Device Patients: Effects of Pulsatility and Thrombus Origin.

This study investigates the hypothesis that by surgically manipulating the outflow graft (OG) implantation during ventricle assist device placement, it may be possible to reduce the risk of cerebral embolism. We investigate this hypothesis using a computational approach on a patient-specific basis under fully pulsatile hemodynamics with a multiscale computational fluid dynamics model incorporating a coupled Eulerian-Lagrangian scheme that effectively tracks emboli in the fluid domain. Blood is modeled as a non-Newtonian fluid based on the hematocrit level. Preliminary flow analysis shows that depending on the anastomosis angle the left ventricular assist device (LVAD) can enhance the flow to the cerebral circulation by nearly 31%. Z-test results suggest that unsteady-flow modeling ought to be an integral part of any cardiovascular simulation with residual ventricular function. Assuming unsteady-flow conditions, a shallow LVAD outflow graft anastomosis angle is the most optimal if thrombi are released from the aortic-root reducing cerebral embolization incidence to 15.5% and from the ventricle to 17%, while a more pronounced anastomosis angle becomes advantageous when particles originate from the LVAD with an embolization rate of 16.9%. Overall, computations suggest that a pronounced LVAD anastomosis angle is the better implementation. Unsteady modeling is shown to be necessary for the presence of significant antegrade aortic-root flow which induces cyclical flow patterns due to residual pulsatility. On the other hand, depending on thrombus origin and ventricular assist devices (VAD) anastomosis angle there is a strong tradeoff in embolization rates.

Gravity Venous Drainage and the 3/8-Inch Venous Line: What Would Poiseuille Do?

The 1/2″ venous line has long been the drainage tubing diameter of choice for adult patients undergoing cardiac surgery. However, several programs use a smaller diameter venous line when used in conjunction with kinetic-assisted venous drainage or vacuum-assisted venous drainage. In 2014, our perfusion team made an institution-wide effort to miniaturize the cardiopulmonary bypass (CPB) circuit for children. One of our changes was the transition to a 3/8″ diameter venous line for drainage, even in our larger patients (up to 80 kg). We reviewed the current literature on this topic and delineated the various parameters required to be able to use the 3/8″ venous line with gravity drainage with the aim of using it on patients up to 115 kg with the appropriate venous reservoir. We have successfully used the 3/8″ venous line in more than 40 of our larger patients (35-90 kg) without the need for assisted venous drainage. We were able to reduce CPB prime from 625 ± 118 to 425 ± 52 mL before retrograde autologous priming (RAP)/venous autologous priming (VAP). The prime was further reduced to 325 ± 66 mL after RAP/VAP. Homologous blood utilization was reduced from 217 ± 311 mL to 27 ± 77 mL. Both results were statistically significant. We hypothesize that taking into account two of the parameters of Poiseuille's law, namely length and diameter, it is possible to safely drain large children and mid-size adults via gravity venous drainage and the 3/8″ venous line. This technique allows reducing prime volume, simplifies CPB circuits with increased safety and potentially reduces the need for homologous blood transfusion.

Patient-specific multiscale computational fluid dynamics assessment of embolization rates in the hybrid Norwood: effects of size and placement of the reverse Blalock-Taussig shunt.

The hybrid Norwood operation is performed to treat hypoplastic left heart syndrome. Distal arch obstruction may compromise flow to the brain. In a variant of this procedure, a synthetic graft (reverse Blalock-Taussig shunt) is placed between the pulmonary trunk and innominate artery to improve upper torso blood flow. Thrombi originating in the graft may embolize to the brain. In this study, we used computational fluid dynamics and particle tracking to investigate the patterns of particle embolization as a function of the anatomic position of the reverse Blalock-Taussig shunt. The degree of distal arch obstruction and position of particle origin influence embolization probabilities to the cerebral arteries. Cerebral embolization probabilities can be reduced by as much as 20% by optimizing graft position, for a given arch geometry, degree of distal arch obstruction, and particle origin. There is a tradeoff, however, between cerebral pulmonary and coronary embolization probabilities.

Risk Factors for an Elevated Ventricular End-Diastolic Pressure Prior to the Fontan Operation.

Systemic ventricular end-diastolic pressure (SVEDP) is an important determinant of pulmonary artery pressure in those with a Fontan circulation. Predictors of an elevated SVEDP have been incompletely identified in this population. All who underwent the Fontan operation at our center between 1/2009 and 12/2013 were retrospectively identified. SVEDP at the pre-Fontan catheterization and other patient variables were extracted. We identified 61 patients. Pre-Fontan SVEDP was positively associated with systemic ventricular systolic pressure (ß = 0.4, p = 0.004), aortic systolic pressure (ß = 0.3, p = 0.007), aortic mean pressure (ß = 0.3, p = 0.02), and decreased ventricular systolic function (p = 0.03). Compared to those with pre-Fontan SVEDP ≤ 7 mmHg, patients with SVEDP > 7 mmHg had higher average ventricular systolic pressure (85.0 ± 7.5 vs. 78.7 ± 8.3 mmHg, p = 0.003), higher average descending aorta mean pressure (62.4 ± 4.9 vs. 58.6 ± 8.1 mmHg, p = 0.03), and a higher incidence of decreased ventricular systolic function (36 vs. 15%, p = 0.07). For those with a systemic right ventricle, the SVEDP decreased significantly from the pre-Stage 2 to pre-Fontan measurements (8.7 ± 2.6 vs. 7.3 ± 2.0 mmHg, p = 0.02), but not for those with a systemic left ventricle (7.8 ± 2.0 vs. 7.2 ± 1.8 mmHg, p = 0.3). At pre-Fontan catheterization, decreased ventricular systolic function and markers of systemic afterload were positively associated with the SVEDP. SVEDP decreased significantly after Stage 2 for those with a systemic right ventricle, but not for those with a systemic left ventricle; the systemic right ventricle may be particularly vulnerable to pre-Stage 2 volume loading.

The Novel Use of a Low Prime Modified Ultrafiltration Apparatus in a 13-kg Jehovah's Witness Patient: A Case Report.

Modified ultrafiltration (MUF) is used in neonates and infants to reduce volume overload and increase oxygen-carrying capacity post cardiopulmonary bypass (CPB). In addition, it decreases edema, attenuates complementation activation and immunogenic response to CPB. Hemodilution in the pediatric patient has always been a challenge, countered in part by miniaturization of CPB circuits. We describe a case in which we maintained an acceptable hematocrit level greater than 24%, considered the nadir below which the adverse effects of hemodilution can become evident. We performed this by the novel use of an intravenous warming device (enFlow, Vyaire Medical, Mettawa, IL) to reduce the prime volume of our MUF circuit by more than 50%. We present the case and discuss the advantages and disadvantages of using a low-prime MUF circuit. We were able to conduct "bloodless" CPB, with the use of acute normovolemic hemodilution, miniaturization of the CPB and MUF circuits.

Bloodless Heart Surgery for an 11-kg Infant of the Jehovah's Witness Faith Undergoing Second Repair for Complete Atrioventricular Canal.

Bloodless pediatric cardiac surgery is the intent of most surgical centers especially in the Jehovah's Witness population where it is a desire not to administer blood products because of religious belief. It is a tremendous feat, considering that most pediatric cardiovascular prime volumes are more than 20% of the patient's estimated blood volume (EBV). We report on our bloodless strategy for a 2-year old Jehovah's Witness with trisomy 21 and complete atrioventricular canal repair, who underwent atrial septal defect and ventricular septal defect patch closure, pulmonary artery debanding, and pulmonary arterioplasty. We modified our circuit to reduce our prime volume to approximately 10% of the EBV and removed 200 mL of the patient's blood before surgery as acute normovolemic hemodilution. We did not alter our institutional standards for transfusion of blood and blood products. The post cardiopulmonary bypass (CPB) hematocrit was 30%. We conclude that bloodless CPB surgery can be performed safely in Jehovah's Witness patients with a carefully planned interdisciplinary approach.

Experimental Study of Anisotropic Stress/Strain Relationships of Aortic and Pulmonary Artery Homografts and Synthetic Vascular Grafts.

Homografts and synthetic grafts are used in surgery for congenital heart disease (CHD). Determining these materials' mechanical properties will aid in understanding tissue behavior when subjected to abnormal CHD hemodynamics. Homograft tissue samples from anterior/posterior aspects, of ascending/descending aorta (AA, DA), innominate artery (IA), left subclavian artery (LScA), left common carotid artery (LCCA), main/left/right pulmonary artery (MPA, LPA, RPA), and synthetic vascular grafts, were obtained in three orientations: circumferential, diagonal (45 deg relative to circumferential direction), and longitudinal. Samples were subjected to uniaxial tensile testing (UTT). True strain-Cauchy stress curves were individually fitted for each orientation to calibrate Fung model. Then, they were used to calibrate anisotropic Holzapfel-Gasser model (R2 > 0.95). Most samples demonstrated a nonlinear hyperelastic strain-stress response to UTT. Stiffness (measured by tangent modulus at different strains) in all orientations were compared and shown as contour plots. For each vessel segment at all strain levels, stiffness was not significantly different among aspects and orientations. For synthetic grafts, stiffness was significantly different among orientations (p < 0.042). Aorta is significantly stiffer than pulmonary artery at 10% strain, comparing all orientations, aspects, and regions (p = 0.0001). Synthetic grafts are significantly stiffer than aortic and pulmonary homografts at all strain levels (p < 0.046). Aortic, pulmonary artery, and synthetic grafts exhibit hyperelastic biomechanical behavior with anisotropic effect. Differences in mechanical properties among vascular grafts may affect native tissue behavior and ventricular/arterial mechanical coupling, and increase the risk of deformation due to abnormal CHD hemodynamics.

The Impact of Roller Pump vs. Centrifugal Pump on Homologous Blood Transfusion in Pediatric Cardiac Surgery.

Centrifugal pumps are considered to be less destructive to blood elements (1) when compared to roller pumps. However, their large prime volumes render them unsuitable as arterial pumps in heart lung machine (HLM) circuitry for children. In November of 2014, the circuit at Arnold Palmer Hospital, a Biomedicus BP-50 with kinetic assist venous drainage (KAVD) and 1/4″ tubing was converted to a roller pump in the arterial position with gravity drainage. Vacuum-assisted venous drainage (VAVD) was mounted on the HLM as a backup, but not used. Tubing was changed to 3/16″ in the arterial line in patients <13 kg. A retrospective study with a total of 140 patients compared patients placed on cardiopulmonary bypass (CPB) with Biomedicus centrifugal pumps and KAVD (Centrifugal Group, n = 40) to those placed on CPB with roller pumps and gravity drainage (Roller Group, n = 100). Patients requiring extra-corporeal membrane oxygenation (ECMO)/cardio-pulmonary support (CPS) or undergoing a hybrid procedure were excluded. Re-operation or circulatory arrest patients were not excluded. Prime volumes decreased by 57% from 456 ± 34 mL in the Centrifugal Group to 197 ± 34 mL in the Roller Group (p < .001). There was a corresponding increase in hematocrit (HCT) of blood primes and also on CPB. Intraoperative homologous blood transfusions also decreased 55% from 422 mL in the Centrifugal Group to 231 mL in the Roller Group (p < .001). The Society of Thoracic Surgeons--European Association for Cardio-Thoracic Surgery (STAT) categorized intubation times and hospital length of stay (LOS) for all infants showed a trend toward reduction, but was not statistically significant. Overall mortality was 5% utilizing the centrifugal configuration and 0% in the roller pump cohort. We demonstrated that the transition to roller pumps in the arterial position of the HLM considerably reduced our priming volume and formed a basis for a comprehensive blood conservation program. By maintaining higher HCTs on CPB, we were able to reduce intraoperative homologous blood transfusions.

Intra-operative arrhythmia predicts post-operative arrhythmia and the need for temporary pacing wires.

OBJECTIVE: Protocols for the placement of temporary pacing wires vary among institutions. Our current protocol is to selectively place temporary pacing wires in those patients who develop haemodynamically significant intra-operative arrhythmia. We wished to identify how effective our current protocol is at identifying who will develop post-operative arrhythmia and need temporary pacing wires. METHODS: The charts of 880 patients over 8 years who underwent cardiopulmonary bypass were reviewed to find patients who developed intra-operative arrhythmia, had temporary pacing wires placed, and whether or not they developed post-operative arrhythmia and required utilisation of the pacing wires. RESULTS: A total of 87 (9.9%) out of 880 patients who required cardiopulmonary bypass over 8 years had intra-operative arrhythmia and had temporary pacing wires placed. Of these, 59 (67.8%) had post-operative arrhythmia and utilised the pacing wires, whereas 28 (32.2%) did not have post-operative arrhythmia or utilise the pacing wires. In all, seven patients who did not have intra-operative arrhythmia or temporary pacing wires placed developed post-operative arrhythmia. CONCLUSION: Intra-operative arrhythmia is predictive of post-operative arrhythmia (70.2%) and our protocol is a sensitive means of identifying those who will develop post-operative arrhythmia (89.3%).

Mathematical modeling of patient-specific ventricular assist device implantation to reduce particulate embolization rate to cerebral vessels.

Stroke is the most devastating complication after ventricular assist device (VAD) implantation, with an incidence of 14%-47% despite improvements in device design and anticoagulation. This complication continues to limit the widespread implementation of VAD therapy. Patient-specific computational fluid dynamics (CFD) analysis may elucidate ways to reduce this risk. A patient-specific three-dimensional model of the aortic arch was generated from computed tomography. A 12 mm VAD outflow-graft (VAD-OG) "anastomosed" to the aorta was rendered. CFD was applied to study blood flow patterns. Particle tracks, originating from the VAD, were computed with a Lagrangian phase model and percentage of particles entering the cerebral vessels was calculated. Twelve implantation configurations of the VAD-OG and three particle sizes (2, 4, and 5 mm) were considered. Percentage of particles entering the cerebral vessels ranged from 6% for the descending aorta VAD-OG anastomosis, to 14% for the ascending aorta at 90 deg VAD-OG anastomosis. Values were significantly different among all configurations (X(2) = 3925, p < 0.0001). Shallower and more cephalad anastomoses prevented formation of zones of recirculation in the ascending aorta. In this computational model and within the range of anatomic parameters considered, the percentage of particles entering the cerebral vessels from a VAD-OG is reduced by nearly 60% by optimizing outflow-graft configuration. Ascending aorta recirculation zones, which may be thrombogenic, can also be eliminated. CFD methods coupled with patient-specific anatomy may aid in identifying the optimal location and angle for VAD-OG anastomosis to minimize stroke risk.

Tailoring left ventricular assist device cannula implantation using coupled multi-scale multi-objective optimization.

BACKGROUND: The frequent occurrence of thromboembolic cerebral events continues to limit the widespread implementation of Ventricular Assist Devices (VAD) despite continued advancements in VAD design and anti-coagulation treatments. Recent studies point to the optimal positioning of the outflow graft (OG) as a potential mitigator of post implantation thromboembolism. OBJECTIVE: This study aims to examine the tailoring of the OG implantation orientation with the goal of minimizing the number of thrombi reaching the cerebral vessels by means of a formal shape optimization scheme incorporated into a multi-scale hemodynamics analysis. METHODS: A 3-D patient-specific computational fluid dynamics model is loosely coupled in a two-way manner to a 0-D lumped parameter model of the peripheral circulation. A Lagrangian particle-tracking scheme models and tracks thrombi as non-interacting solid spheres. The loose coupling between CFD and LPM is integrated into a geometric shape optimization scheme which aims to optimize an objective function that targets a drop in cerebral embolization, and an overall reduction in particle residence times. RESULTS: The results elucidate the importance of OG anastomosis orientation and placement particularly in the case that studied particle release from the OG, as a fivefold decrease in cerebral embolization was observed between the optimal and non-optimal implantations. Another case considered particle release from the ventricle and aortic root walls, in which optimal implantation was achieved with a shallow insertion angle. Particle release from all three origins was investigated in the third case, demonstrating that the optimal configurations were generally characterized by VAD flow directed along the central lumen of the aortic arch. Because optimal configurations depended on the anatomic origin of the thrombus, it is important to determine, in clinical studies, the most likely sites of thrombus formation in VAD patients.

Cilia and Nodal Flow in Asymmetry: An Engineering Perspective.

Over the past several years, cilia in the primitive node have become recognized more and more for their contribution to development, and more specifically, for their role in axis determination. Although many of the mechanisms behind their influence remain undocumented, it is known that their presence and motion in the primitive node of developing embryos is the determinant of the left-right axis. Studies on cilial mechanics and nodal fluid dynamics have provided clues as to how this asymmetry mechanism works, and more importantly, have shown that direct manipulation of the flow field in the node can directly influence physiology. Although relatively uncommon, cilial disorders have been shown to have a variety of impacts on individuals from chronic respiratory infections to infertility, as well as situs inversus which is linked to congenital heart disease. After first providing background information pertinent to understanding nodal flow and information on why this discussion is important, this paper aims to give a review of the history of nodal cilia investigations, an overview of cilia mechanics and nodal flow dynamics, as well as a review of research studies current and past that sought to understand the mechanisms behind nodal cilia's involvement in symmetry-breaking pathways through a biomedical engineering perspective. This discussion has the additional intention to compile interdisciplinary knowledge on asymmetry and development such that it may encourage more collaborative efforts between the sciences on this topic, as well as provide insight on potential paths forward in the field.

Research Enterprise of the Congenital Heart Surgeons' Society 2018 to 2023: History, Accomplishments, Transformation, and Challenges.

The history of the research arm of the Congenital Heart Surgeons' Society (CHSS) through 2017 was contained within two prior publications that covered CHSS history in general. The present article is the first to focus explicitly on the research enterprise, with emphasis on the period 2018 to 2023. During this time, the challenges of continuing to build multiple cohorts with lifelong follow-up and to transform the enterprise to a premiere research organization became manifest. Although continuing its commitment to produce impactful research results and to educate the Kirklin/Ashburn Fellow, the research team devoted considerable effort to defining the problems of cohort relevance, workflow, data management, long-term patient follow-up, CHSS member engagement, and the regulatory burden. The team wrote a proposal outlining ways to solve the challenges. A major change from a single-institution "Data Center" to a two-institution Center for Research & Quality (CRQ) was made, assuring increased faculty members and resources. The proposed changes to structure and process began execution in mid-2022. A second Kirklin/Ashburn Fellowship position was created. Between 2018 and 2022, the CRQ produced 17 publications and launched five new research initiatives. This article chronicles the exciting five-year period in which the CHSS research enterprise began a transformation with the intent to become the premiere research organization in the world in the specialty of congenital cardiac surgery.

Invited Commentary: Notwithstanding the Significance of Anatomy in Anomalous Aortic Origin of a Coronary Artery, Physiology Is Important, Too.

The management strategies for anomalous aortic origin of a coronary artery (AAOCA) are based on anatomy, symptoms, and stress tests for evidence of ischemia. These strategies remain associated with low levels of evidence. Stress tests for ischemia or ventricular dysfunction, the only widely used physiological tests, are not adequately reliable. Additional physiological metrics are needed to build reliable strategies. Fractional flow reserve (FFR) and instantaneous wave-free ratio (iFR) are physiological measurements that are used in assessing acquired coronary artery disease (CAD). In this commentary, we describe FFR and iFR and review studies supporting their utility in assessing CAD. We describe a few small studies of their use in assessing AAOCA. Finally, we comment on the unique features of AAOCA that mandate further investigation on how to conduct and interpret FFR/iFR measurements. Even at a point where we understand how to do this, determining the effectiveness of these measurements in improving outcomes and guiding management will require lengthy and challenging trials. A collective effort of institutions that manage AAOCA will be essential.

Mycotic Pseudoaneurysm: Rare Complication of a Norwood/Sano Graft Stump.

The Sano variant of the stage 1 Norwood procedure is commonly performed as initial palliation for hypoplastic left heart syndrome. We present a case of a 2-year-old who developed a mycotic pseudoaneurysm of the Sano graft and discuss the importance of imaging and operative management of this rare presentation. Localization and full description of the lesion require compulsive, often multimodality imaging.

In-Silico and In-Vitro Analysis of the Novel Hybrid Comprehensive Stage II Operation for Single Ventricle Circulation.

Single ventricle (SV) anomalies account for one-fourth of all congenital heart disease cases. The existing palliative treatment for this anomaly achieves a survival rate of only 50%. To reduce the trauma associated with surgical management, the hybrid comprehensive stage II (HCSII) operation was designed as an alternative for a select subset of SV patients with the adequate antegrade aortic flow. This study aims to provide better insight into the hemodynamics of HCSII patients utilizing a multiscale Computational Fluid Dynamics (CFD) model and a mock flow loop (MFL). Both 3D-0D loosely coupled CFD and MFL models have been tuned to match baseline hemodynamic parameters obtained from patient-specific catheterization data. The hemodynamic findings from clinical data closely match the in-vitro and in-silico measurements and show a strong correlation (r = 0.9). The geometrical modification applied to the models had little effect on the oxygen delivery. Similarly, the particle residence time study reveals that particles injected in the main pulmonary artery (MPA) have successfully ejected within one cardiac cycle, and no pathological flows were observed.

Persistent Hypoxia After Blunt Thoracic Trauma due to Flail Tricuspid Valve Leaflet and Patent Foramen Ovale.

Structural cardiac injury after blunt trauma is uncommon but usually life-threatening. While tricuspid injury is very rare and potentially lethal, the right heart can accommodate larger volumes and higher pressures in acute tricuspid insufficiency and facilitate initial stabilization prior to definitive valvular repair. ECMO may be used to ameliorate resulting right heart failure. The traumatic force required to cause cardiac structural injury is also associated with pulmonary complications related to pneumothorax, hemothorax, effusion, acute pain secondary to rib fractures, and pulmonary contusions causing hypoxia. We present an unusual case of hypoxia in a trauma patient caused by acute tricuspid regurgitation with pre-existing patent foramen ovale.