Artery Shunt Research Articles

Graft Aberrant Hepatic Arteries in Deceased Donor Liver Transplantation: The "One Liver, One Artery" Approach

Introduction: In liver transplantation (LT), aberrant hepatic arteries (aHA) frequently require complex arterial reconstructions during graft implantation, potentially increasing the risk of postoperative complications. The physiological presence of intrahepatic hilar arterial shunts may allow selective non-conservative aHA management. The aim of this study was to assess the impact of a selective reconstruction approach of aHAs on deceased-donor LT(DDLT) outcomes.

A swine model of reproducible timed induction of peripheral arterial shunt failure: Developing warning signs of imminent shunt failure

Temporary intravascular shunts are used to maintain perfusion in injured vessels, although failure can be unpredictable and lead to significant morbidity. The aim of the present study was to develop a dose- and timing-controlled swine model of intrinsic shunt failure to facilitate the development of a warning system for impending failure. Ten Yorkshire swine (weight, 56.6 ± 4.2 kg) underwent bilateral Argyle shunt (Cardinal Health, Dublin, OH) placement in the external iliac arteries, with proximal cannulation of the circumflex iliac arteries for infusion of thrombin. The thrombin infusion was randomized to the left or right side for 5000 vs 10,000 U/h. The 5000-U/h group required 2.1 times as long as the 10,000-U/h group to reach failure (mean, 21.8 minutes vs 46.4 minutes; P < .0001), as shown by a Kaplan-Meier survival analysis (log-rank P < .0001). However, the 5000-U/h group required the same total amount of thrombin (mean, 3752 ± 856 U; P = .57). Thus, time- and/or thrombin dose-controlled induction of shunt failure is technically feasible. Furthermore, in the final 15 minutes before failure, the flow was similar between the two groups (P > .05), and the slope of the flow curve became more negative the closer the model was to failure. Overall, this model could be used to develop an alert system to predict for impending shunt failure or the need for intervention.

Ductus Arteriosus Stent Compared with Surgical Shunt for Infants with Ductal-Dependent Pulmonary Blood Flow: A Systematic Review and Meta-Analysis

The aim of this study was to perform a systematic review and meta-analysis to evaluate the safety and efficacy of ductus arteriosus stent (DAS) compared with surgical systemic-pulmonary artery shunt (SPS) in patients with ductal-dependent pulmonary blood flow. A literature search was conducted in PubMed, Embase, and the Cochrane Library databases from their inception to December 2020. Two reviewers independently screened the articles, evaluated the quality of the articles, and collected the data. Meta-analyses were conducted using fixed and random effects models. We used the I-square (I2 ) test to examine heterogeneity and the funnel plot Egger’s test was used to test for publication bias. We analyzed nine studies including 842 patients were included in the present study (DAS: n = 295; SPS: n = 547). There was a benefit in favor of DAS group for medium-term mortality (RR, 0.63; 95% CI, [0.40, 0.99]; P = 0.91, I2 = 0%). DAS group demonstrated a reduced risk for complications compared with SPS (RR, 0.46; 95% CI, [0.29, 0.72]; P = 0.78, I2 = 0%). There was an increased risk for unplanned reintervention for DAS (RR, 1.77; 95% CI, [1.42, 2.20]; P = 0.61, I2 = 0%). DAS demonstrated shorter mean intensive care unit length of stay (MD, –5.12; 95% CI, [–7.33, –2.91]; P = 0.005, I2 = 76%). There was also demonstrated higher postprocedure oxygen saturation for SPS over DAS (MD, 1.78; 95% CI, [0.92, 2.64]; P = 0.46, I2 = 0%). There was no difference between the two groups in terms of mortality within 30 days, Nakata Index, and hospital length of stay. Conclusions: In terms of initial palliative surgical in the ductal-dependent pulmonary blood flow, DAS demonstrated a lower risk of medium-term mortality, lower risk of complications, higher risk of unplanned reintervention, shorter ICU length of stay, and higher postprocedure oxygen saturation compared with SPS.

Double aortic arch: an elusive diagnosis in a child with CHD.

An 18-month-old male with pulmonary atresia and ventricular septal defect presented with stridor after neonatal systemic-to-pulmonary artery shunt surgery, that persisted on follow-up. CT angiography revealed a vascular ring with balanced double aortic arch.

Abstract 10502: Impact of Norwood Shunt Type on Cardiac Function and Clinical Outcomes in Survivors to Early Adolescence with Hypoplastic Left Heart Syndrome and Other Single Right Ventricular Anomalies: A Report from the Single Ventricle Reconstruction (SVR) III Study

Introduction: The SVR Trial demonstrated that the right ventricle-to-pulmonary artery shunt (RVPAS) vs. modified Blalock-Taussig-Thomas shunt (MBTTS) at Norwood operation was associated with better early survival for children with hypoplastic left heart syndrome (HLHS). However, it remains unclear if shunt type is associated with cardiac function, morbidities or survival in older children. Methods: SVR Trial survivors were followed annually. Cardiac MRI and cycle ergometry were performed at 10-12 years (y) of age for SVR III participants. Outcomes were compared by shunt type received (presented) and intention to treat, using linear, Poisson and Cox proportional hazards regression. Results: Among 549 children in the SVR Trial, 237 of 313 eligible transplant-free survivors returned for follow-up at median (IQR) 10.9 (10.4-11.5) y. Transplant-free survival at 12 y was 59% for the RVPAS vs 54% for the MBTTS, with no difference in survival conditional on Stage II survival. Ejection fraction (EF) was measured by MRI in 168 participants, with no difference between groups (RVPAS median 53 [IQR 46-58] and MBTTS 52 [IQR 48-56], p=.38). In multivariable modeling, the percent variance in EF explained by pre-Norwood and Norwood variables including shunt type was low (R 2 &lt; .2). Cycle ergometry was performed in 181 participants with no difference by shunt type in peak VO 2 (ml/kg/minute) (RVPAS 30 [IQR 25-36] vs. MBTTS 29 [IQR 24-33], p=.26) or in peak work rate (RVPAS 67±24 watts vs MBTTS 66±20 watts, p=.61). By age 12 y, the RVPAS group had a higher rate of PLE (5% vs. 2%, p =.04) and catheter interventions (14 vs 10 per 100 pt-y; p=0.01). Otherwise the cumulative incidence of events and complications were similar for shunt groups with stroke in 7%, seizure 14%, plastic bronchitis 1%, atrial tachyarrhythmias 7% and ventricular tachyarrhythmias 3%. Conclusion: By 12 y after Norwood, shunt type has minimal effect on post-Stage II transplant-free survival, cardiac function or exercise performance. EF is preserved in most transplant-free survivors. However, low and declining transplant-free survival, poor exercise performance, and accruing morbidities highlight the critical need for innovative strategies to improve long-term outcomes in patients with HLHS.

Tratamento cirúrgico de persistência de ducto arterioso – relato de caso

The ductus arteriosus is an arterial shunt between the aorta and a pulmonary artery, physiological during fetal development, during this period it shunts away part of the blood circulation that would go to the lungs, which at that moment are still afunctional. After birth, there is a physiological closure of this duct, its non-occlusion is called persistent ductus arteriosus (PDA), which is treated surgically. We report the clinical case of a female canine of the German dwarf spitz breed that was diagnosed with PDA in a routine pediatric pre-vaccination consultation. Doppler echocardiography was then performed with confirmation of PDA. Treatment consisted of surgical correction using the standard technique of ligation of the patent ductus arteriosus. The procedure was successful with the patient's recovery.

Complications After Surgical Repair of Congenital Heart Disease in Infants. An Experience From Tertiary Care Center.

ObjectivesThis study aimed to describe the incidence and spectrum of postoperative complications in infants who underwent their first cardiac surgery for the repair of congenital heart diseases.MethodsThis is a single-center retrospective study. Data of infants admitted to King Faisal Specialist Hospital & Research Center; Jeddah; Saudi Arabia, from January 2015 to December 2019 who underwent the first cardiac procedure for congenital heart disease at an age of less than 3 months, were analyzed. The primary outcome is the prevalence and spectrum of postoperative complications during hospitalization. Data were analyzed by using descriptive and analytical statistics using SAS software version 9.4.ResultsData of 130 procedures were analyzed. The most frequent procedure performed was the Norwood procedure (31.5%), aortic coarctation repair (13.8%), arterial switch operation (13%), and Blalock-Taussig and central shunts (10%). The overall postprocedural complications were reported in 96 (73.8%) of the procedures. The most frequent complications were prolonged postoperative mechanical ventilation (27%), pleural effusion (21%), excessive bleeding (19%), cardiac arrest (18%), and systemic infections (18%).ConclusionCardiac surgery for congenital heart disease in young infants has a substantial risk for postoperative complications. The high incidence of these complications in these cases makes necessary attention to prove the outcomes in the cardiac centers.

Sternotomy versus Mini-Sternotomy in Pediatric Patients undergoing Modified Blalock-Taussig Shunt

Abstract Background In the present era, primary correction is the preferred approach to the neonate or young infant with a cardiac anomaly who has two ventricles. However, when only one functional ventricle is present or pulmonary blood flow is reduced, an initial palliative systemic-to-pulmonary arterial shunt is mandatory. In this study we compare post-operative short term outcomes of sternotomy versus mini-sternotomy approaches in pediatric patients undergoing Modified Blalock Taussig Shunt. Patients and Methods A prospective randomized study was conducted on 90 patients who were schedueled for MBT shunt due to a group of cyanotic heart disease. They comprised 2 groups G1: sternotomy group (n = 45) and G2: ministernotomy group (n = 45). Results Mean age was 11± 3.39 months and mean weight was 6.75±1.96 kg in the sternotomy group, while for ministernotomy group the mean age was 10.55± 4.65 and mean weight was 7.00±2.03 kg. The change (%) between preoperative and postoperative oxygen saturation was 35.6% for sternotomy group and 43.8% for ministernotomy group. There were seven cases of mortality (15.6%) in sternotomy grouped compared to three cases of mortality (6.7%) in ministernotomy with P value of 0.314. Superficial wound infection occurred in one case (2.2%) in each group. Mean duration of ventilation was 52.53 ± 15.76 h for sternotomy group and 46.93±19.23 h for ministernotomy group with P value of 0.025, mean ICU stay was 7.42 ± 2.94 days for sternotomy group and 5.13± 2.37 days for ministernotomy with P value of &amp;lt; 0.001. Conclusion Upper ministernotomy is a safe alternative approach for MBT shunt in pediatric patients. It provides the advantages of less ventilation time, less post operative bleeding, and ICU stay.

OUTCOMES OF PALLIATIVE RIGHT VENTRICLE TO PULMONARY ARTERY CONNECTION FOR TETRALOGY OF FALLOT WITH PULMONARY ATRESIA AND MAPCAS

<h3>BACKGROUND</h3> Tetralogy of Fallot with pulmonary atresia with major aorto pulmonary artery collaterals (TOF-PA MAPCAS) is a rare and complex cyanotic congenital heart malformation with a high incidence of early mortality and morbidity. Different surgical interventions have been described including construction of a systemic to pulmonary artery shunt (Modified Blalock-Taussig shunt or central shunt) and unifocalization, however the perioperative mortality remains significant due to the high incidence of thrombosis, obstruction, and pulmonary artery (PA) distortion. Another alternative is a palliative right ventricle to pulmonary artery connection (RVPAC) to bring antegrade flow to diminutive PAs. The objective of our study was to evaluate the impact of RVPAC on mortality, survival, morbidity, PA growth and eligibility for biventricular repair. We believe that the RVPAC approach allows for better PA growth and obviates the need for a conduit at the time of complete repair. <h3>METHODS AND RESULTS</h3> We performed a retrospective single-institution study from January 2016 to March 2021 that included 15 consecutive patients diagnosed with TOF-PA MAPCAS who underwent an RVPAC at CHU Sainte-Justine as their initial palliation. Median age at palliation and complete repair was 18 (4 -100) and 309 (96 – 1044) days respectively. Mortality after a RVPAC was 0 % with a median hospital length of stay of 14,5 days (6 - 55), while the late interstage mortality rate was 0 %. Overall survival was 100 %. 9 patients (60%) had a biventricular repair, and 6 patients (40%) are awaiting repair. RVPAC allowed significant growth of the native pulmonary arteries with a mean Nakata index at CT scan of 70 ± 48,04 mm2/m2 before the RVPAC and 251 ± 121,05 mm2/m2 after (P = 0.001). 4 patients (44%) required reinterventions after completed repair by catheterization for stenotic pulmonary artery branches, while no patients required a late reoperation. 8 patients (53,33%) had embolization of collaterals and none required unifocalization. <h3>CONCLUSION</h3> This reproducible and safe technique allows for excellent growth of the PA tree. Biventricular repair was possible in most cases without the use of a conduit or unifocalization of collaterals. This technique appears to be suitable for any type of TOF-PA MAPCAS with confluent native branch pulmonary arteries.

Postoperative Renal Failure, Shunt Type, and Mortality After Norwood Palliation

BackgroundThe Single Ventricle Reconstruction Trial demonstrated increased risk of death or heart transplant 1 year after Norwood among subjects randomly assigned to modified Blalock-Taussig shunts compared with right ventricle to pulmonary artery (RV-PA) shunts. We used the Single Ventricle Reconstruction Trial public use database to evaluate incidence and risk factors for postoperative renal failure and relationships between renal failure, shunt type, and outcomes after Norwood. MethodsPostoperative renal failure was defined a priori as a threefold rise in creatinine from baseline, or dialysis use, within 7 days of Norwood. We used multivariate logistic regression to evaluate risk factors for postoperative renal failure and Cox hazard regression to determine the association between postoperative renal failure and 1 year after Norwood mortality. ResultsOverall, postoperative renal failure occurred in 8.4% (46 of 544) patients with risk factors including receipt of a modified Blalock-Taussig shunt (adjusted odds ratio [aOR] 3.3, P = .02), low center volume (aOR 2.7, P = .005), two or more preoperative complications (aOR 4.0, P < .001), low birth weight (aOR 3.2, P = .002), postoperative heart block (aOR 8.5, P = .001), and delayed sternal closure (aOR 5.3, P = .026). Renal failure was an independent risk factor for 1-year mortality (aHR 1.9, P = .019). Assessing interaction by shunt type, mortality risk associated with renal failure was greatest in the RV-PA shunt group (aHR 3.3 vs RV-PA shunt without renal failure, P = .001), but was also increased in the modified Blalock-Taussig shunt group (aHR 1.9, P = .03). ConclusionsPostoperative renal failure is common after Norwood and is independently associated with mortality. Although renal failure is more common after modified Blalock-Taussig shunt, the highest mortality risk with renal failure occurs after RV-PA shunt.

Delayed presentation of massive haemoptysis from aortic aneurysm after aortic coarctation repair (a case report).

IntroductionMassive haemoptysis refers to coughing and losing a huge amount of blood in a 24-hour period. It's a life-threatening condition with high mortality rate.Case presentationWe report a rare case of massive haemoptysis in a 60-year-old female patient who had aortic coarctation repair 30 years ago. Her Computed tomography (CT) angiography showed huge aneurysmal dilatation and dissection of the descending thoracic aorta at the site of the repair. Thoracic endovascular aortic repair (TEVAR) was done, but the patient had recurrent massive haemoptysis due to extension of the aneurysm to the aortic arch. The patient then underwent one stage surgical right to left carotid artery shunt followed by TEVAR to the aortic arch covering the left common carotid artery. The procedure was successful, and haemoptysis was controlled without any complications.DiscussionIn this case the high index of suspicion for thoracic aortic aneurysm in patients presenting with haemoptysis and prior history of coarctation repair were demonstrated.Conclusionmassive haemoptysis in patients who had aortic coarctation repair is an alarming sign, and surgical intervention is required. TEVAR has become one of the best approaches for managing aortic aneurysm and has replaced open repair.

Novel technique of achieving hemodynamic stability during systemic to pulmonary artery shunt.

Historically, the Blalock Taussig (BT) shunt has been an off-pump procedure. For the last two decades, the number of BT shunt operations has come down globally with the adoption of neonatal early corrective surgery. BT shunts are still performed for augmentation of pulmonary arterial (PA) growth or as a part of univentricular palliation. Many infants do not tolerate PA branch clamping while undergoing the graft to PA anastomosis, necessitating institution of cardiopulmonary bypass (CPB). Since the threshold to go on CPB for shunt placement is quite low at most institutions, our technical modification described can avoid deleterious effect of CPB. Our point of interest is to maintain lung perfusion by adopting few principles of off-pump coronary artery bypass surgery.

Selection of optimal endarterectomy technique in the left anterior descending artery for diffuse coronary atherosclerosis

Aim. To determine the optimal method for performing coronary artery endarterectomy (СE) based on immediate and long-term outcomes of coronary artery bypass grafting (CABG) in combination with open or closed CE in the left anterior descending artery (LAD).Material and methods. This retrospective study included 103 patients who underwent CABG in combination with closed CE and 204 after open CE in the LAD during the period from 2003 to 2016. In both groups, the patient age was comparable (65 years [56; 69] vs 67 years [58; 72] (p=0,263)). There were more men (88,3% vs 81,4% (p=0,421). The mean follow-up period was 94 months [38; 180]. Long-term outcomes were assessed in 86,4% (n=89) and 83,8% (n=171) of patients from the closed and open CE groups, respectively (p=0,141). Angiographic data were studied in 75,3% and 67,3% of patients, respectively (p=0,441).Results. In the closed and open CE groups, in-hospital mortality was 4,8% and 1,5% (p=0,0012), incidence of perioperative myocardial infarction — 11,6% vs 2,5%, (p&lt;0,001), survival rate after 7,8 years — 81,3±5,1% and 84,4±3,2% (p=0,342), respectively. The patency of arterial shunts was significantly higher in the open CE group — 93,1% vs 80,6% (p=0,004). At the same time, the patency of venous shunts in the long-term period between the groups was comparable — 70,1% vs 73,7% (p=0,314).Conclusion. Open CE in combination with CABG provides better immediate outcomes compared to closed CE. Long-term survival and freedom from angina between the groups were comparable. In the long-term period, the patency of internal thoracic artery after open CE is better than after the closed technique. Open CE is a safe and effective method to achieve complete myocardial revascularization in patients with severe diffuse LAD atherosclerosis.

Involvement of Neutrophil Extracellular Traps in Cerebral Arteriovenous Malformations

Cerebral arteriovenous malformations (cAVMs) represent tangles of abnormal vasculature without intervening capillaries. High-pressure vascular channels due to abnormal arterial and venous shunts can lead to rupture. Multiple pathways are involved in the pathobiology of cAVMs including inflammation and genetic factors such as KRAS mutations. Neutrophil release of nuclear chromatin, known as neutrophil extracellular traps (NETs), plays a multifunctional role in infection, inflammation, thrombosis, intracranial aneurysms, and tumor progression. However, the relationship between NETs and the pathobiology of cAVMs remains unknown. We tested whether NETs play a role in the pathobiology of cAVMs. We analyzed samples from patients who had undergone surgery for cAVM and immunohistochemically investigated expression of citrullinated histone H3 (CitH3) as a marker of NETs. CitH3 expression was compared among samples from cAVM patients, epilepsy patients, and normal human brain tissue. Expressions of thrombotic and inflammatory markers were also examined immunohistochemically in samples from cAVM patients. Expression of CitH3 derived from neutrophils was observed intravascularly in all cAVM samples but not other samples. Nidi of AVMs showed migration of many Iba-I-positive cells adjacent to the endothelium and endothelial COX2 expression, accompanied by expression of IL-6 and IL-8 in the endothelium and intravascular neutrophils. Unexpectedly, expression of CitH3 was not necessarily localized to the vascular wall and thrombus. Our results offer the first evidence of intravascular expression of NETs, which might be associated with vascular inflammation in cAVMs.

Pulmonary-to-Systemic Arterial Shunt to Treat Children With Severe Pulmonary Hypertension

BackgroundThe placement of a pulmonary-to-systemic arterial shunt in children with severe pulmonary hypertension (PH) has been demonstrated, in relatively small studies, to be an effective palliation for their disease. ObjectivesThe aim of this study was to expand upon these earlier findings using an international registry for children with PH who have undergone a shunt procedure. MethodsRetrospective data were obtained from 110 children with PH who underwent a shunt procedure collected from 13 institutions in Europe and the United States. ResultsSeventeen children died in-hospital postprocedure (15%). Of the 93 children successfully discharged home, 18 subsequently died or underwent lung transplantation (20%); the mean follow-up was 3.1 years (range: 25 days to 17 years). The overall 1- and 5-year freedom from death or transplant rates were 77% and 58%, respectively, and 92% and 68% for those discharged home, respectively. Children discharged home had significantly improved World Health Organization functional class (P < 0.001), 6-minute walk distances (P = 0.047) and lower brain natriuretic peptide levels (P < 0.001). Postprocedure, 59% of children were weaned completely from their prostacyclin infusion (P < 0.001). Preprocedural risk factors for dying in-hospital postprocedure included intensive care unit admission (hazard ratio [HR]: 3.2; P = 0.02), mechanical ventilation (HR: 8.3; P < 0.001) and extracorporeal membrane oxygenation (HR: 10.7; P < 0.001). ConclusionsA pulmonary-to-systemic arterial shunt can provide a child with severe PH significant clinical improvement that is both durable and potentially free from continuous prostacyclin infusion. Five-year survival is comparable to children undergoing lung transplantation for PH. Children with severely decompensated disease requiring aggressive intensive care are not good candidates for the shunt procedure.

Performance of a novel temporary arterial shunt in a military-relevant controlled hemorrhage swine model.

In military trauma, temporary vascular shunts restore arterial continuity until delayed vascular reconstruction, often for a period of hours. A novel US Air Force-developed trauma-specific vascular injury shunt (TS-VIS) incorporates an accessible side port for intervention or monitoring, which may improve patency under adverse hemodynamic conditions. Our objective was to evaluate TS-VIS patency in the setting of volume-limited resuscitation from hemorrhagic shock. Female swine (70-90 kg) underwent 30% hemorrhage and occlusion of the left external iliac artery for 30 minutes. Animals were allocated to one of three groups (n = 5 per group) by left external iliac artery treatment: Sundt shunt (SUNDT), TS-VIS with arterial pressure monitoring (TS-VIS), or TS-VIS with heparin infusion (10 μ/kg per hour, TS-VISHep). Animals were resuscitated with up to 3 U of whole blood to maintain a mean arterial pressure (MAP) of >60 mm Hg and were monitored for 6 hours. Bilateral femoral arterial flow was continuously monitored with transonic flow probes, and shunt thrombosis was defined as the absence of flow for greater than 5 minutes. No intergroup differences in MAP or flow were observed at baseline or following hemorrhage. Animals were hypotensive at shunt placement (MAP, 35.5 ± 7.3 mm Hg); resuscitation raised MAP to >60 mm Hg by 26.5 ± 15.5 minutes. Shunt placement required 4.5 ± 1.8 minutes with no difference between groups. Four SUNDT thrombosed (three before 60 minutes). One SUNDT thrombosed at 240 minutes, and two TS-VIS and one TS-VISHep thrombosed between 230 and 282 minutes. Median patency was 21 minutes for SUNDT and 360 minutes for both TS-VIS groups (p = 0.04). While patent, all shunts maintained flow between 60% and 90% of contralateral. The TS-VIS demonstrated sustained patency superior to the Sundt under adverse hemodynamic conditions. No benefit was observed by the addition of localized heparin therapy over arterial pressure monitoring by the TS-VIS side port.

RBC Transfusion Induced ST Segment Variability Following the Norwood Procedure.

Retrospective case-control study. Nine-hundred seventy-three-bed pediatric hospital with a 54-bed cardiovascular ICU. Seventy-three neonates with hypoplastic left heart syndrome following the Norwood procedure, 38 with a Blalock-Taussig shunt and 35 with a right ventricle to pulmonary artery shunt. RBC transfusion. High-frequency physiologic data were captured 30 minutes prior to the initiation of (baseline) and during the 120 minutes of the transfusion. A rate pressure product was calculated for each subject and used as an indicator of myocardial oxygen demand. Electrocardiogram leads (aVL, V1, II) were used to construct a 3D ST segment vector to assess ST segment variability and functioned as a surrogate indicator of myocardial ischemia. One-hundred thirty-eight transfusions occurred in the Blalock-Taussig shunt group and 139 in the right ventricle to pulmonary artery shunt group. There was no significant change in the rate pressure product for either group; however, ST segment variability progressively increased for the entire cohort during the transfusion, becoming statistically significant by the end of the transfusion. Upon subgroup analysis, this finding was noted with statistical significance in the Blalock-Taussig shunt group and trending toward significance in the right ventricle to pulmonary artery shunt group. We found a significant increase in the ST segment variability and evidence of myocardial ischemia temporally associated with RBC transfusions in neonates following the Norwood procedure, specifically among those in the Blalock-Taussig shunt group, which may impact immediate and long-term outcomes.

Preoperative risk factors influencing inter-stage mortality after the Norwood procedure.

With improvements in early survival after the stage I palliation (S1P) Norwood procedure for hypoplastic left heart syndrome (HLHS) and its variants, inter-stage death accounts for an increasing proportion of mortality. Our aim was to identify the risk factors for inter-stage mortality. The records of 322 neonates with HLHS or a variant who underwent the Norwood procedure at our centre between 2001 and 2019 were retrospectively analysed. The diagnoses included 271 neonates with HLHS (84%) and 51 with variants (16%). Aortic atresia was observed in 138 (43%) patients, mitral atresia in 91 (28%), extracardiac anomalies in 42 (13%) and genetic disorder in 14 (4%). The median age and weight of the patients at the S1P Norwood procedure were 9 (interquartile range: 7-12) days and 3.2 (2.9-3.5) kg, respectively. The median cardiopulmonary bypass time was 137 (107-163) min. Modified Blalock-Taussig shunts were used in 159 (49%) and unvalved right ventricle-to-pulmonary artery shunts in 163 (51%) patients. The number of inter-stage deaths was as follows: between S1P and stage II palliation (S2P), 61 including 38 early (<30 days) and 23 late (>30 days) deaths, and between S2P and stage III palliation, 32 deaths. Low birth weight (<2.5 kg) (odds ratio 4.37, P = 0.020) and restrictive atrial septum (odds ratio 2.97, P = 0.013) were identified as risks for early mortality. Low birth weight [hazard ratio (HR) 0.99/g, P = 0.002] was a risk for inter-stage mortality between S1P and S2P. Extracardiac anomalies (HR 4.75, P = 0.049) and significant pre-S1P atrioventricular valve regurgitation (HR: 7.72, P = 0.016) were risks for inter-stage mortality between S2P and stage III palliation. Other anatomical variables including aortic atresia, anatomical subtypes and the diameter of the ascending aorta nor shunt type were not identified as risk factors for mortality during any inter-stage period. The risk factors for inter-stage attrition after the Norwood procedure were different between each stage. Preoperative factors, including birth weight, restrictive atrial septum and extracardiac anomalies, adversely affected the inter-stage mortality.

Transpleural systemic artery-to-pulmonary artery communications in the absence of chronic inflammatory lung disease. A case series and review of the literature

To describe the causes and computed tomography (CT) and angiographic appearances of transpleural systemic artery-to-pulmonary artery shunts in patients without chronic inflammatory lung disease and determine their best management. All patients referred to a tertiary referral unit between January 2009 and January 2020 in whom a diagnosis of a systemic-to-pulmonary artery communication without underlying chronic inflammatory lung disease was subsequently made have been included in this report. Medical records and imaging findings were reviewed retrospectively. Ten patients (male: female ratio=7:3; median age 42 years [range 22-70 years]) with systemic artery-to-pulmonary artery shunts without chronic inflammatory lung disease were identified. Five were misdiagnosed as having a pulmonary arteriovenous malformation and had been referred for embolisation. In six patients, there was either a history of accidental or iatrogenic thoracic trauma or of inflammatory disease involving the pleura, and in two patients, in whom a previous medical history could not be obtained, there were CT features suggesting previous pleural inflammatory disease. Two shunts were thought to be congenital. All individuals were asymptomatic other than one with localised thoracic discomfort that dated from the time of surgery. All patients were managed conservatively and have remained well with a median follow-up of 4.5 years (range 1-11.3 years). Localised transpleural systemic artery-to-pulmonary artery shunts in the absence of chronic inflammatory lung disease are usually related to previous thoracic trauma/intervention or abdominal or pulmonary sepsis involving a pleural or diaphragmatic surface. Congenital shunts are rare. The present study and much of the literature supports conservative management.

Can ankle-brachial index be used as a predictor for carotid artery shunt application during carotid endarterectomy?

Objectives: This study aims to investigate the possible relationship between low ankle-brachial index (ABI) and shunt requirement during carotid endarterectomy (CEA) operations. Patients and methods: Medical records of a total of 56 patients (40 males, 16 females; mean age: 65.6±8.4 years; range, 48 to 82 years) who underwent CEA between January 2013 and December 2016 were retrospectively reviewed. The ABI was measured in all patients at the time of hospital admission. Peripheral arterial disease was defined as having an ABI of ≤0.90 in either leg. Selective carotid artery shunt strategy was applied to all patients who underwent CEA under regional anesthesia. Results: Forty-eight (85.8%) patients were symptomatic. Peripheral arterial disease was diagnosed in 25 (44.6%) patients with ABI measurements. Eleven (19.6%) patients required shunt placement due to neurological deterioration during the carotid clamping test. The mean ABI of 11 (19.6%) patients was 0.8±0.15, while the ABI was less than 0.90 in 10 (17.8%) patients. There was a statistically significant correlation between perioperative shunt usage and peripheral arterial disease (odds ratio [OR]: 19.68, 95% confidence interval [CI]: 2.3-164.4; p=0.001). Conclusion: Low ABI appears to be related to a higher rate of shunt requirement in patients undergoing CEA under regional anesthesia with a selective shunt strategy in our modest cohort.