Patent Ductus Arteriosus Shunt Research Articles

Patent ductus arteriosus management in very-low-birth-weight prematurity: a place for an early operation?

The goal was to evaluate neonatal outcomes based on treatment strategies and time points for haemodynamically significant patent ductus arteriosus (hsPDA) in very-low-birth-weight preterm infants, with a particular focus on surgical closure. This retrospective study included very-low-birth-weight infants born between 2014 and 2021 who received active treatment for hsPDA. Neonatal outcomes were compared between (i) primary surgical closure versus primary ibuprofen; (ii) early (<14th post-natal day) versus late primary surgical closure (≥14th post-natal day); and (iii) primary versus secondary surgical closure after ibuprofen failure. Further analysis using 1:1 propensity score matching was performed. Logistic regression was conducted to analyse the risk factors for post-ligation cardiac syndrome (PLCS) and/or acute kidney injury (AKI). A total of 145 infants with hsPDA underwent active treatment for closure. The in-hospital death rate and the incidence of severe bronchopulmonary dysplasia (BPD) were similar between the primary surgical closure group and the primary ibuprofen group in a 1:1 matched analysis. Severe BPD was significantly higher in the late surgical closure group than in the early primary surgical closure group with 1:1 propensity score matching (72.7% vs 40.9%, P=0.033). The secondary surgical closure group showed the mildest clinical condition; however, the probability of PLCS/AKI was highest (38.6%) compared to the early (15.2%) or the late primary surgical group (28.1%, P<0.001), especially in extremely premature infants (gestational age < 28 weeks). Surgical patent ductus arteriosus closure is not inferior to pharmacologic treatment. Considering the harmful effect of a prolonged patent ductus arteriosus shunt exposure, a timely decision and timely efforts should be made to minimize the risk of severe BPD and PLCS/AKI after surgical closure.

Role of maternal hyperoxygenation testing to predict need for balloon atrial septostomy in fetal d-transposition of great arteries.

Predicting whether balloon atrial septostomy (BAS) will be necessary after birth for fetuses with d-transposition of the great arteries (d-TGA) remains challenging. We sought to determine whether measurements obtained during fetal maternal hyperoxygenation (MH) testing can improve our ability to predict need for postnatal BAS. Forty-one mothers carrying fetuses with d-TGA with either intact ventricular septum or small ventricular septal defect measuring <3mm underwent MH testing between 33-38 weeks gestation. Patent foramen ovale (PFO) size, measured by 2D and color Doppler, patent ductus arteriosus (PDA) shunting (all antegrade versus bidirectional) was assessed in room air (RA) and during MH, blinded to postnatal outcome. BAS status and timing were recorded. Postnatally, 23 neonates underwent BAS while 18 did not, and 14 subjects underwent emergent BAS within 3 hours of life. By univariate analysis, PFO size measured both in RA and MH and all antegrade shunting in the PDA during MH predicted BAS. During MH testing, median PFO size by 2D measured 2.5mm (interquartile range, IQR, 2-3mm) in fetuses who underwent emergent BAS versus 4.1mm (IQR 3.4-5mm) in fetuses who did not undergo BAS (p<0.001). By cutpoint analysis, PFO size during MH testing ≤ 3.2mm predicted need for emergent BAS with sensitivity 93% and specificity 78%. In d-TGA, measurement of PFO size and direction of PDA shunting during MH testing improves our ability to predict need for BAS postnatally, although additional study is needed. We propose incorporating third trimester MH testing when planning deliveries of d-TGA fetuses. This article is protected by copyright. All rights reserved.

Computed tomographic assessment of bronchoesophageal artery hypertrophy and systemic‐to‐pulmonary shunt mimicking a persistent ductus arteriosus in a French Bulldog

AbstractA 5‐year‐old, female French bulldog was evaluated for left‐sided congestive heart failure. A diagnosis of bronchoesophageal artery hypertrophy with systemic‐to‐pulmonary shunt was made. Even though Doppler echocardiographic findings were in favour of a left‐to‐right shunting patent ductus arteriosus, the exploratory thoracotomy highlighted a more complex vascular anomaly. An angiographic computed tomography study allowed to establish the final diagnosis. Bronchial‐to‐pulmonary artery shunts can mimic the presence of a patent ductus arteriosus, therefore computed tomography is considered a valuable additional tool for diagnosis and surgical planning.

Patent ductus arteriosus shunting direction and diameter predict inpatient outcomes in newborns with congenital diaphragmatic hernia.

To evaluate whether the patent ductus arteriosus (PDA) can serve as a predictive factor for inpatient outcomes in congenital diaphragmatic hernia (CDH) patients. A retrospective cohort study was conducted on 59 CDH patients at the Capital Institute of Pediatrics from January 2020 to August 2022. Echocardiography was performed at least three times: within 2-3 h after birth, pre-operatively, and post-operatively of CDH surgery. Based on the direction of the PDA shunt in the first echocardiogram, patients were classified into three groups: left-to-right shunting or closed PDA (L-R), bi-directional shunting, and right-to-left shunting (R-L). The mortality rate was 15.3% (9/59), with all non-survivors having R-L shunting and group mortality of 39.1% (9/23). The direction of the PDA shunt was significantly associated with the duration of ventilation and length of hospital stay (p < 0.05). Decreased PDA diameter or pre-operative shunting direction change towards L-R or bi-directional shunting were associated with higher survival rates, while increased PDA diameter or continuous R-L shunting were associated with higher mortality rates. Pre-operative PDA shunt direction, PDA size after birth and before surgery, gestational age of diagnosis, and shortening fraction before surgery were significantly correlated with patient outcomes. The direction of the preoperative PDA shunt was the most relevant factor among these relationships (p = 0.009, OR 20.6, CI 2.2∼196.1). Our findings highlight the importance of monitoring changes in PDA shunt directionality and diameter in the early stage after birth, as these parameters may serve as valuable predictors of patient outcomes.

Successful Percutaneous Closure of Complicated Residual Patent Ductus Arteriosus Shunts Resembling Pig Nostrils Following Second-Time Surgical Treatment

Successful Percutaneous Closure of Complicated Residual Patent Ductus Arteriosus Shunts Resembling Pig Nostrils Following Second-Time Surgical Treatment

Risk factors for intraoperative hemorrhage and perioperative complications and short- and long-term outcomes during surgical patent ductus arteriosus ligation in 417 dogs.

To evaluate the short- and long-term outcomes of dogs undergoing surgical ligation for a left-to-right shunting patent ductus arteriosus (PDA), identify risk factors for intraoperative hemorrhage and intra- and postoperative complications, and report overall mortality rates. 417 client-owned dogs undergoing surgical ligation for a left-to-right shunting PDA between January 2010 and January 2020. Data recorded included patient signalment, echocardiogram findings, intraoperative complications and mortality, postoperative complications, and short- and long-term outcomes. There was no association between age and risk of intraoperative hemorrhage (P = .7), weight and intraoperative hemorrhage (P = .96), or increasing left atrium-to-aortic (LA:Ao) ratio and intraoperative hemorrhage (P = .08). Intraoperative hemorrhage occurred in 10.8% of patients. Intraoperative mortality was 2%. Ninety-five percent of dogs experiencing intraoperative hemorrhage survived to discharge. Survival to discharge was 97%. One- and 5-year survival rates were 96.4% and 87%, respectively. Surgical ligation for a left-to-right shunting PDA is recommended due to the good long-term prognosis. Certain preoperative factors such as age, weight, and the presence and degree of mitral valve regurgitation had no detectable association with risks of intraoperative hemorrhage and, therefore, should not preclude surgical treatment for a left-to-right shunting PDA. Future studies are needed to further assess the association between increasing LA:Ao ratio and risk of intraoperative hemorrhage.

Patent ductus arteriosus (PDA) and pulmonary morbidity: can early targeted pharmacologic PDA treatment decrease the risk of bronchopulmonary dysplasia?

A persistent left-to-right shunt through a patent ductus arteriosus (PDA) increases the rate of pulmonary hydrostatic fluid filtration, impairs pulmonary mechanics, and prolongs the need for respiratory support. Infants with a moderate/large PDA shunt that persists for more than 7-14 days are at increased risk for developing bronchopulmonary dysplasia (BPD) if they also require invasive ventilation for more than 10 days. In contrast, infants who require invasive ventilation for less than 10 days have similar rates of BPD no matter how long they are exposed to a moderate/large PDA shunt. Although pharmacologic PDA closure decreases the risk of abnormal early alveolar development in preterm baboons that are ventilated for 2 weeks, the findings from recent randomized controlled trials, as well as a quality improvement project, suggest that routine early targeted pharmacologic treatments, as currently employed, do not appear to alter the incidence of BPD in human infants.

Anaesthetic management of a dog with a bidirectionally shunting patent ductus arteriosus and concurrent pulmonary hypertension

AbstractA 1‐year‐old, 9.8‐kg (21.6‐lb), female, spayed Pembroke Welsh corgi dog was presented for evaluation of previously diagnosed patent ductus arteriosus and severe pulmonary hypertension. In the veterinary literature, there is relatively little information related to the anaesthetic management of patients with patent ductus arteriosus and severe pulmonary hypertension (or in those with Eisenmenger pathophysiology). In this case report, we consider haemodynamic concerns related to anaesthesia in this clinical setting, while describing the successful management of this case and related complications.

Impact of patent ductus arteriosus shunt size and duration on risk of death or severe respiratory morbidity in preterm infants born in China

The purpose of this study is to assess whether duration and size of the arterial duct were associated with severe respiratory morbidity and mortality in preterm infants. All echocardiography evaluations for patent ductus arteriosus (PDA) in a cohort of preterm infants, born at a gestational age less than 28 weeks, from birth up to 36 weeks of postconceptional age or final ductal closure were reviewed. Ductal size was measured at the pulmonary end. PDA was classified as small (E1: ductal diameter (DD) ≤ 1.5 mm), moderate (E2: 1.5 mm < DD ≤ 2.5 mm), or large (E3) (DD > 2.5 mm). The primary outcome was adverse outcome defined by the composite outcome of bronchopulmonary dysplasia (BPD) or death. Infants in whom the primary outcome occurred were classified as “high-risk” whereas patients who did not satisfy this outcome were classified as “low-risk”. Intergroup comparison (high vs. low risk) was performed using univariate and multivariate analyses. A total of 135 infants, born between 2010 and 2020, were evaluated. The primary outcome was satisfied in 46 (34.1%) patients. The high-risk group was characterized by increased duration of exposure to PDA of any (E1/E2/E3) grade (44 vs. 25.5 days, p = .0004), moderate or large (E2/E3) PDA (30.5 vs. 11.5 days, p < .0001), moderate (E2) PDA (10.8 vs.6 days, p = 0.05), and large (E3) PDA (11.5 vs.0 days, p < .0001) compared with low-risk group. Lower gestational age, prolonged duration of mechanical ventilation, higher rate of inotrope use, pharmacological therapy, and PDA ligation were also associated with development of BPD or death (high-risk group). After adjusting for confounders, the rate of inotrope use [OR 2.688, 95% CI (1.011–7.142), p = 0.047], duration of large (E3) PDA [OR 1.060, 95% CI (1.005–1.118), p = 0.03], and mechanical ventilation [OR 1.130, 95% CI (1.064–1.200), p = 0.0001] were independently associated with the composite of BPD or death. Among infants who developed BPD, 27 were classified as grade I and 18 as grade II BPD, respectively. Infants with grade II BPD had prolonged MV (20.0 vs. 9.0 days, p = 0.024), prolonged exposure to PDA of any grade (55.8 vs. 36.0 days, p = 0.03), and prolonged exposure to large (E3) PDA compared with infants with grade I BPD. Conclusion: Prolonged exposure to a large PDA was associated with severe respiratory morbidity and mortality in preterm infants. The modulator role of early intervention, in the most pathologic shunts, on severe respiratory morbidity in preterm infants should be tested in well-designed clinical trials.What is Known:• Current guidelines recommended against accelerating PDA closure of preterm infants within 2 weeks of life, with low certainty evidence indicating improved long-term outcomes.• Recent studies suggest that conservative approach regarding PDA management has detrimental effects on the respiratory outcomes in a subgroup population.What is New:• Persistent patency of significant PDA is associated with increased risk of BPD/death in extremely preterm infants.• Targeted intervention of PDA is beneficial for the at-risk preterm infants with increased PDA hemodynamic significance.

A simple noninvasive biomarker can reflect both the acute and chronic pulmonary impact of patent ductus arteriosusshunting.

The SFR (SpO2 /FiO2 ratio) offers a continuous, noninvasive reflection of pulmonary function regardless of whether the baby is ventilated or breathing spontaneously. We hypothesized that significant patent ductus arteriosus (PDA) shunting would impair pulmonary oxygen diffusion, reflected by decreased SFR; and that early PDA related decreases in SFR predict subsequent chronic lung disease (CLD). We retrospectively examined records from preterm neonates ≤30 weeks gestational age. Ductal shunting was graded for severity by first week echocardiogram. SFR was calculated as SpO2 /FiO2 and recorded on Day 7 of life and 36 weeks postmenstrual age (PMA). We studied 104 infants: 65 with closed duct,17 with hemodynamically insignificant PDA, and 22 with hemodynamically significant (hsPDAs). CLD developed in 9 (14%) of those with closed ducts; 6 (35%) of those with hisPDA; and in 12 (55%) of those with hsPDA (p = 0.005). SFR values at 1 week postnatally were decreased in those with hsPDA and with hisPDA as compared with those with closed ducts(closed ducts 452 [448-457]vs.hisPDA 396 [294-442]vs.hsPDA 327 [235-369]; p = 0.00001). However, at 36 weeks only SFRs of babies with hsPDA remained significantly lower (467 [461-467]vs.467 [413-471]vs.369 [262-436]for closed vs.hisPDA vs.hsPDA respectively; p = 0.000148). Using ROC curve analysis, Week 1 SFR was strongly associated with hsPDA (area under curve [AUC] = 0.770; p < 0.0001) and highly predictive (AUC = 0.801; p < 0.0001) of CLD at 36 weeks PMA. Early decreases in SFR reflect both the acute and chronic pulmonary impact of PDA shunting, possibly providing the missing link supporting an association between hemodynamically significant PDA and subsequent CLD.

Management of the patent ductus arteriosus in preterm infants.

Management of the patent ductus arteriosus (PDA) is one of the most contentious topics in the care of preterm infants. PDA management can be broadly divided into prophylactic and symptomatic therapy. Prophylaxis with intravenous indomethacin in extremely low birth weight infants may reduce severe intraventricular hemorrhage. Echocardiography should be routinely used to confirm the presence of a PDA before considering symptomatic therapy. A symptomatic PDA can be managed conservatively, using pharmacotherapy or with procedural closure. Ibuprofen should be considered as the pharmacotherapy of choice for a symptomatic PDA. High-dose ibuprofen may be preferable, especially for preterm infants beyond the first 3 to 5 days of age. If pharmacotherapy fails (after two courses) or is contraindicated, procedural closure may be considered for infants with a persistent PDA with significant clinical symptoms in addition to echocardiographic signs of a large PDA shunt volume and pulmonary over-circulation.

Assessment of superior vena cava flow and cardiac output in different patterns of patent ductus arteriosus shunt

Despite the widespread use of superior vena cava (SVC) flow as a marker of systemic blood flow from the upper body, no previous studies have systematically evaluated the correlation between SVC flow and other echocardiography measures of systemic blood flow in the context of different patterns of patent ductus arteriosus (PDA) shunt direction METHODS: A retrospective cohort study of preterm infants (<30weeks,<21 days of life) who underwent comprehensive targeted neonatal echocardiography (TnECHO) was performed. Patients were categorized as follows: (i) Hemodynamically significant left-to-right shunt; (ii): Bidirectional shunt; (iii) No PDA or insignificant shunt. SVC flow, as measured by two distinct methods, was compared to left and right ventricular outputs (LVO and RVO). Intra- and inter-observer reliability testing was performed RESULTS: In total, 45 patients were included (15 in each group) with a median [IQR] weight of 720 [539, 917] grams at the time of assessment. SVC dimensions and flow measurements were not different between the groups, although patients with left-to-right shunt had higher LVO/RVO ratio. SVC flow, as estimated using the modified method, had a strong correlation with LVO (r=.63, p=0.012) and RVO (r=.635, p=0.011) in patients with no PDA. Inter- and intra-observer reliability were both stronger for LVO and RVO when compared to SVC flow measurements CONCLUSION: SVC flow was comparable across all three groups irrespective of higher LVO and LVO/RVO ratio in patients with left-to-right shunts. This may reflect poor measurement reliability or compensation for left-to-right ductal shunt by increased LVO to maintain systemic perfusion.

AORTIC FLOW PROPAGATION VELOCITY AND ITS RELATION TO MAGNITUDE OF SHUNT IN PATIENTS WITH ISOLATED PATENT DUCTUS ARTERIOSUS

Background: Patent ductus arteriosus (PDA) is normally associated with hyperdynamic status. Given the presence of a vascular shunt between the aorta and pulmonary artery, intrinsic aortic changes occur (aortic stiffness). Arterial stiffness is currently regarded as an independent predictor of cardiovascular morbidity and mortality. There is a close relationship between arterial stiffness and aortic flow propagation velocity (AFPV). Objective: To assess aortic stiffness in patients with isolated PDA using Doppler-derived AFPV, assess shunt magnitude i.e. pulmonary to systemic blood flow ratio (QP/QS) in patients with isolated PDA by echocardiography, compare AFPV values in patients with isolated PDA and apparently healthy individuals, and to correlate AFPV with PDA size and shunt magnitude. Patients and Methods: Our study was performed at Bab EL-Sha'riya Hospital, Al-Azhar University during the period from September 2019 and August 2020, and consisted of twenty-five patients with isolated PDA, and twenty healthy controls. Detailed history, physical examination was performed and conventional two-dimensional echocardiography was done to all cases then echocardiographic assessment of PDA including magnitude of the shunt by measuring QP/QS ratio. Aortic flow propagation velocity (AFPV) was measured in all cases. Results: Patients with PDA exhibited significantly lower AFPV than the control (p < 0.001). AFPV was significantly correlated with systolic blood pressure (r= -0.29 &p= 0.01). Also, there was significant correlation (r=-0.426) between AFPV and PDA size, mainly pulmonary end (p=0.03), and magnitude of the shunt QP/QS (r= 0.723 & p < 0.001). Conclusion: Transthoracic echocardiographic determination of the color M-mode propagation velocity of the descending aorta is a simple, non-invasive practical surrogate method in identifying arterial stiffness in patients with PDA and is related to effective orifice of PDA and magnitude of the shunt.

The use of Amplatzer vascular plug II in 32 consecutive dogs for transvenous occlusion of patent ductus arteriosus

ObjectivesTo describe the use of the Amplatzer vascular plug II (AVPII) for transvenous occlusion of patent ductus arteriosus in a non-selective population of dogs, with a focus on the surgical technique, short term outcome and associated complications. Animals, materials and methodsRetrospective study. Records of thirty-two consecutive dogs treated for a left-to-right shunting patent ductus arteriosus with the AVPII were reviewed. ResultsDuctal occlusion with an AVPII occlusion device was attempted in 32 dogs weighing 1.1–53.8 kg. Transvenous occlusion was successful in 30 dogs. One dog required a transarterial approach for occlusion. One dog died during catheterisation of the right heart but prior to transductal catheterisation. Mean ductal ampulla diameter was 7.9 mm (range, 4.1–15.4 mm) and median size of deployed devices was 10 mm (range 4–20 mm). Mean device to ampulla ratio was 1.34 ± 0.15. Device was positioned in situ with no residual flow on follow-up echocardiographic assessment (> one month) in all dogs where deployment was attempted. Occlusion success rate was 96.9% and mortality rate was 3.1%. Four dogs (13.3%) demonstrated minor complications, with none having long-term significance. ConclusionsThe use of AVPII device via a transvenous approach is a feasible and effective method for occlusion of a left-to-right shunting patent ductus arteriosus in dogs of a wide range of weight. The method described may complement existing catheter-based occlusion methods.

Patent ductus arteriosus, tracheal ventilation, and the risk of bronchopulmonary dysplasia

BackgroundAn increased risk for bronchopulmonary dysplasia (BPD) exists when moderate-to-large patent ductus arteriosus shunts (hsPDA) persist beyond 14 days.GoalTo examine the interaction between prolonged exposures to tracheal ventilation (≥10 days) and hsPDA on the incidence of BPD in infants <28 weeks gestation.Study DesignPredefined definitions of prolonged ventilation (≥10 days), hsPDA (≥14 days), and BPD (room air challenge test at 36 weeks) were used to analyze deidentified data from the multicenter TRIOCAPI RCT in a secondary analysis of the trial.ResultsAmong 307 infants who survived >14 days, 41 died before 36 weeks. Among survivors, 93/266 had BPD. The association between BPD and hsPDA depended on the length of intubation. In multivariable analyses, prolonged hsPDA shunts were associated with increased BPD (odds ratio (OR) (95% confidence interval (CI)) = 3.00 (1.58–5.71)) when infants required intubation for ≥10 days. In contrast, there was no significant association between hsPDA exposure and BPD when infants were intubated <10 days (OR (95% CI) = 1.49 (0.98–2.26)). A similar relationship between prolonged hsPDA and length of intubation was found for BPD/death (n = 307): infants intubated ≥10 days: OR (95% CI) = 2.41 (1.47–3.95)); infants intubated <10 days: OR (95% CI) = 1.37 (0.86–2.19)).ConclusionsModerate-to-large PDAs were associated with increased risks of BPD and BPD/death—but only when infants required intubation ≥10 days.ImpactInfants with a moderate-to-large hsPDA that persist beyond 14 days are only at risk for developing BPD if they also receive prolonged tracheal ventilation for ≥10 days.Infants who receive less ventilatory support (intubation for <10 days) have the same incidence of BPD whether the ductus closes shortly after birth or whether it persists as a moderate-to-large shunt for several weeks.Early PDA closure may be unnecessary in infants who require short durations of intubation since the PDA does not seem to alter the incidence of BPD in infants who require intubation for <10 days.

Patent ductus arteriosus shunt elimination results in a reduction in adverse outcomes: a post hoc analysis of the PDA RCT cohort.

A post hoc appraisal of the PDA RCT to assess the relationship between early patent ductus arteriosus (PDA) shunt elimination and chronic lung disease or death (CLD/Death). Infants <29 weeks were divided into four groups: intervention arm in whom PDA closure was achieved (n = 17); intervention arm in whom PDA closure was not achieved (n = 13); placebo arm (n = 30); low risk infants (n = 13). The main outcome measure was CLD/Death. The rates of CLD/Death were lower in the Intervention Success Group (29%) when compared to the Intervention Failure Group (85%) or the Placebo Group (60%, all p < 0.05). There was no difference in CLD/Death between the Intervention Success and Low Risk Groups (8%, p > 0.05). A persistent PDA beyond Day 8 was associated with CLD/Death (aOR 6.5 [1.7-25.5]). Early shunt elimination in preterm infants with a PDA may reduce respiratory morbidity when compared to infants with prolonged shunt exposure.

Transarterial correction of patent ductus arteriosus in small dogs with the Amplatz™ Vascular Plug 4: A pilot study

ObjectivesDetermine if the Amplatz™ Vascular Plug 4 (AVP4) can be used to occlude left-to-right shunting patent ductus arteriosus (PDA) in dogs with inadequate arterial vascular access for the Amplatz Canine Duct Occluder (ACDO). AnimalsSix adolescent dogs with PDA whose femoral artery was too small for insertion of a 4 Fr vascular access sheath. Materials and methodsStandard femoral arterial vascular access and a 4 Fr diagnostic catheter were used to deploy an appropriately sized AVP4 into the PDA of each dog. Successful occlusion was defined as no residual ductal flow and determined by color Doppler echocardiography and angiography. ResultsThe AVP4 was successfully deployed, and complete occlusion of the PDA was achieved in all dogs. There were no complications encountered in any of the dogs. ConclusionsThe AVP4 is a viable option for the correction of PDA in dogs with inadequate arterial vascular access for the ACDO and should be considered as one of the options available for PDA correction in this challenging animal population.

Clinical features and outcome of dogs and cats with bidirectional and continuous right-to-left shunting patent ductus arteriosus.

BackgroundStudies describing the clinical progression of animals with reverse patent ductus arteriosus (PDA) are lacking.ObjectivesTo describe the signalment, presenting signs, echocardiographic features, and survival in a group of dogs and cats with bidirectional and continuous right‐to‐left PDA.AnimalsForty‐six client‐owned animals included, comprising 43 dogs and 3 cats with bidirectional or continuous right‐to‐left PDA.MethodsRetrospective multicenter study. Medical records and echocardiographic findings reviewed from animals diagnosed with bidirectional or continuous right‐to‐left PDA. Impact of ductal morphology, spectral Doppler flow profile, PCV, sildenafil treatment at presentation, sildenafil dose, severity of pulmonary hypertension, general anesthesia with or without surgery and the presence of right‐sided congestive heart failure (R‐CHF) on crude mortality rate were evaluated via Mantel‐Cox log rank comparison of Kaplan‐Meier survival curves. Univariable and multivariable Cox proportional hazards analysis was performed, and hazard ratio (HR) (95% confidence intervals [CI]) was presented.ResultsHindlimb collapse was the most common presenting sign in dogs (n = 16). Clinical signs in cats were variable. Median survival time was 626 days in dogs (range 1‐3628 days). Dogs with R‐CHF had a shorter median survival time (58 days vs 1839 days, P = .03). Dogs treated with sildenafil at initial presentation survived longer (1839 days vs 302 days, P = .03), which was the only independent predictor of survival (HR 0.35, CI 0.15‐0.86, P = 0.021).Conclusions and Clinical ImportanceDogs and cats with reverse PDA have a variable clinical presentation and prognosis. Survival time was longer in animals prescribed sildenafil at diagnosis. Dogs with R‐CHF at presentation have a worse overall outcome.

Alternative anaesthetic management in a reintervention for correction of a left‐to‐right shunting patent ductus arteriosus (PDA) in a dog

AbstractA three‐year‐old, male neutered, 2.7 kg Chihuahua was referred for correction of a type IIA, left‐to‐right shunting PDA. The correction of the PDA required two separate interventions. During the first intervention, a minimally invasive transvascular correction of the PDA that was converted to a thoracotomy was suspended after the evidence of iatrogenic haemopericardium. The second intervention, scheduled after the resolution of the haemopericardium, consisted of surgical ligation of the PDA via thoracotomy. Long periods of hypotension (mean arterial pressure below 60 mm Hg) were observed during the first intervention, during which anaesthesia was maintained with a combination of sevoflurane and infusions of fentanyl and lidocaine. The use of total intravenous anaesthesia with alfaxalone in conjunction with locoregional techniques in the second intervention provided smooth anaesthesia with improved cardiovascular stability.

Branham sign in dogs undergoing interventional patent ductus arteriosus occlusion or surgical ligation: a retrospective study.

Background:The Branham sign is a baroreceptor response that follows patent ductus arteriosus (PDA) closure. Although described in dogs following both interventional and surgical ductal closure, a direct comparison of the Branham sign elicited by these two techniques has not been made.Aim:Since closure with an Amplatz canine ductal occluder (ACDO) occurs over 10 minutes and surgical ligation (SL) is more rapid, we hypothesized that the Branham sign following occlusion of a PDA with an ACDO would be less severe than following SL.Methods:Clinical records of dogs diagnosed with left-to-right shunting PDA between 2008 and 2018 were retrospectively reviewed. Of 139 dogs undergoing PDA occlusion, only 41 dogs (ACDO n = 32, SL n = 9) were included after applying exclusion criteria. Heart rate (HR) and blood pressure (BP) from occlusion time (T0) until 30 minutes post occlusion (T30) were recorded. Signalment and anesthetic protocol were also recorded. The influence of age and weight on the hemodynamic variations was assessed. Hemodynamic variables and calculations were compared between and within groups using a repeated measures general linear model, and post hoc tests were applied if significance was identified.Results:A mild Branham sign was present in both groups, and hemodynamic changes were not significantly different between groups. In both groups, there was a significant decrease in HR (11 bpm, 5.3–16.3; p < 0.001) (10.4%, 5.4–15.5; p < 0.001) and increase in diastolic BP (9.5 mmHg, 3–16; p = 0.002) (23.5%, 7.1–39.9; p = 0.002), but systolic BP did not change significantly (p = 0.824). Age and weight did not influence Branham sign.Conclusion:The Branham sign in dogs is mild in both groups, lasts for at least 30 minutes, and is independent of the method of PDA closure.