Invasive haemodynamics predict outcomes in paediatric pulmonary artery hypertension

BACKGROUND

Invasive haemodynamics are often performed for initiating and guiding pulmonary artery hypertension therapy. Little is known about the predictive value of invasive haemodynamic indices for long-term outcomes in children with pulmonary artery hypertension. We aimed to evaluate invasive haemodynamic data to help predict outcomes in paediatric pulmonary artery hypertension.

METHODS

Patients with pulmonary artery hypertension who underwent cardiac catheterisation (2006-2019) at a single centre were included. Invasive haemodynamic data from the first cardiac catheterisation and clinical outcomes were reviewed. The combined adverse outcome was defined as pericardial effusion (due to right ventricle failure), creation of a shunt for pulmonary artery hypertension (atrial septal defect or reverse Pott's shunt), lung transplant, or death.

RESULTS

Among 46 patients with a median [interquartile range (IQR)] age of 13.2 [4.1-44.7] months, 76% had CHD. Median mean pulmonary artery pressure was 37 [28-52] mmHg and indexed pulmonary vascular resistance was 6.2 [3.6-10] Woods units × m2. Median pulmonary artery pulsatility index was 4.0 [3.0-4.7] and right ventricular stroke work index was 915 [715-1734] mmHg mL/m2. After a median follow-up of 2.4 years, nine patients had a combined adverse outcome (two had a pericardial effusion, one underwent atrial level shunt, one underwent reverse Pott's shunt, and six died). Patients with an adverse outcome had higher systolic and mean pulmonary artery pressures, higher diastolic and transpulmonary pressure gradients, higher indexed pulmonary vascular resistance, higher pulmonary artery elastance, and higher right ventricular stroke work index (p < 0.05 each).

CONCLUSION

Invasive haemodynamics (especially mean pulmonary artery pressure and diastolic pressure gradient) obtained at first cardiac catheterisation in children with pulmonary artery hypertension predicts outcomes.

Amplatzer Vascular Plug closure of an iatrogenic interatrial tunnel-type communication

A 50-year-old woman who had atrial septal defect surgery at 11 months old underwent ascending aortic aneurysm resection and two attempts at closure of a residual atrial septal defect. Post-operatively, she had severe cyanosis. She was referred to our centre where a transesophageal echocardiogram and cardiac catheterisation showed an iatrogenic interatrial tunnel-type communication that was closed with an Amplatzer Vascular Plug.

Novel Score to Predict Immunoglobulin Resistance in Kawasaki Disease

To evaluate existing scoring systems and develop a new model to predict intravenous immunoglobulin (IVIG) resistance in patients with Kawasaki disease (KD). A retrospective cohort study performed between 2004 and 2017 identified 115 patients treated with IVIG for classic or incomplete KD. In our practice, IVIG resistance was defined as fever for > 24 h and patients were divided into responders and non-responders. A univariate analysis was performed to identify independent predictors of IVIG resistance. The predictors were combined into a new scoring system and compared with existing scoring systems. Sixty-five patients had classic KD and 50 had incomplete KD. Among the 115 patients, 80 (69.6%) responded and the remaining 35 were resistant (30.4%) to IVIG. Of the 35 resistant patients, 16 patients had incomplete KD. Hispanic children comprised 43% of our sample population. Coronary artery abnormalities developed in 14 of the 35 IVIG-resistant patients (39%). Univariate analysis showed that IVIG-resistant patients were older and present with lower platelets, potassium, and creatinine (P < 0.05). Multivariate logistic regression analysis used platelets, potassium, body surface area (BSA), and creatinine to devise the Las Vegas Scoring System (LVSS), which demonstrated a sensitivity of 76.2% and a specificity of 68.6%. Compared to published data, we observed a higher rate of IVIG resistance and coronary artery abnormalities in our patient population. The LVSS (using platelets, potassium, BSA, and creatinine) showed higher specificity and comparable sensitivity to other scoring systems devised to predict IVIG resistance.

A Bioinformatic Algorithm based on Pulmonary Endoarterial Biopsy for Targeted Pulmonary Arterial Hypertension Therapy

Background

Optimal pharmacological therapy for pulmonary arterial hypertension (PAH) remains unclear, as pathophysiological heterogeneity may affect therapeutic outcomes. A ranking methodology based on pulmonary vascular genetic expression analysis could assist in medication selection and potentially lead to improved prognosis.

Objective

To describe a bioinformatics approach for ranking currently approved pulmonary arterial antihypertensive agents based on gene expression data derived from percutaneous endoarterial biopsies in an animal model of pulmonary hypertension.

Methods

We created a chronic PAH model in Micro Yucatan female swine by surgical anastomosis of the left pulmonary artery to the descending aorta. A baseline catheterization, angiography and pulmonary endoarterial biopsy were performed. We obtained pulmonary vascular biopsy samples by passing a biopsy catheter through a long 8 French sheath, introduced via the carotid artery, into 2- to 3-mm peripheral pulmonary arteries. Serial procedures were performed on days 7, 21, 60, and 180 after surgical anastomosis. RNA microarray studies were performed on the biopsy samples.

Results

Utilizing the medical literature, we developed a list of PAH therapeutic agents, along with a tabulation of genes affected by these agents. The effect on gene expression from pharmacogenomic interactions was used to rank PAH medications at each time point. The ranking process allowed the identification of a theoretical optimum three-medication regimen.

Conclusion

We describe a new potential paradigm in the therapy for PAH, which would include endoarterial biopsy, molecular analysis and tailored pharmacological therapy for patients with PAH.

CAR Selectively Enhances the Pulmonary Vasodilatory Effect of Fasudil in a Microsphere Model of Pulmonary Hypertension

Background

Despite the approval of several medications for pulmonary hypertension, morbidity and mortality are unacceptably high. Systemic hypotension may limit the use of pulmonary hypertension medications.

Objectives

This study aimed to assess whether the homing peptide CAR (CARSKNKDC) improves the vasodilatory selectivity of fasudil in the pulmonary circulation or systemic circulation in a porcine pulmonary hypertension model.

Materials and Methods

Pulmonary hypertension (to approximately 2/3-3/4 systemic pressure levels) was induced by chronic and acute administration of microspheres in 3 micro Yucatan pigs (mean weight 19.9 kg, mean age 4.3 months). Fasudil (0.3 mg/kg) was administered without and with CAR (1.5 mg/kg), and the effect on aortic (Ao) and right ventricular (RV) pressure was recorded with indwelling catheters.

Results

Immediately after fasudil administration, there was a decrease in Ao pressure followed by prompt recovery to baseline. The RV pressure decrease was progressive and sustained. Fasudil alone resulted in a 12% decrease in RV pressure, whereas co-administration of CAR with fasudil resulted in a 22% decrease in RV pressure (p < 0.0001). Fasudil alone caused an average decrease of 34% in the RV/Ao pressure ratio, and fasudil + CAR caused an average decrease of 40% in the RV/Ao pressure ratio (p < 0.0001).

Conclusion

The homing peptide CAR selectively enhanced the acute vasodilatory effects of fasudil on the pulmonary vascular bed in a porcine experimental model of pulmonary hypertension.

Hepatic Fibrosis Risk Factors in Extracardiac-Fontan Patients: Observations From a Single Center

Objective: We reviewed our experience with transvenous liver biopsy-derived hepatic fibrosis scores and possible associated risk factors in those postextracardiac Fontan patients. Methods: We identified extracardiac-Fontan patients with postoperative durations <20 years who underwent cardiac catheterizations with transvenous hepatic biopsies between April 2012 and July 2022. If a patient underwent two liver biopsies, we averaged the two total fibrosis scores and concurrent time, pressure, and oxygen saturation data. We grouped patients by the following factors: (1) sex, (2) venovenous collaterals, and (3) type of functionally univentricular heart. We identified potential hepatic fibrosis risk factors as the following: female, presence of venovenous collaterals, and a functional univentricle of right-ventricular type. For statistical analysis, we used Kruskal-Wallis nonparametric testing. Results: We identified 127 patients who underwent 165 transvenous biopsies, with 38 patients undergoing 2 biopsies. We found that females with two additional risk factors had the highest median total fibrosis scores, 4 (1-8); males with <2 risk factors had the lowest median total fibrosis scores, 2 (0-5); and females with <2 additional risk factors and males with two risk factors were in the middle, median total fibrosis score 3 (0-6), P =.002; and there were no statistical differences for the other demographic or hemodynamic variables. Conclusions: For extracardiac-Fontan patients with similar demographic and hemodynamic variables, identifiable risk factors are associated with the degree of hepatic fibrosis.

Prenatal diagnosis of hypoplastic aortic arch without intracardiac malformations: The nevada experience

OBJECTIVE

We reviewed our center's experience with neonatal and infant hypoplastic aortic arch, unassociated with intracardiac malformations, and investigated changes in prenatal detection rates over time for those requiring therapeutic procedures.

METHODS

We identified all prenatal diagnoses of hypoplastic aortic arch with situs solitus, unassociated with intracardiac malformations, made in Nevada between May 2017 and April 2022. In addition, we identified all those 0-180 days old, with prenatal care, that underwent a surgical or interventional cardiac catheterization aortic arch procedure, whether prenatally or postnatally diagnosed. We excluded those with ventricular septal defects, functionally univentricular hearts, interrupted aortic arches, or any associated malformation requiring an additional surgical or interventional procedure ≤6 months old. Additionally, we calculated prenatal detection rates for those undergoing a surgical or interventional catheterization procedure for each of the 5 years.

RESULTS

We identified 107 patients prenatally and postnatally. Of the 107 patients, 56 (34 prenatally diagnosed and 22 postnatally diagnosed) underwent an aortic arch procedure, and 51 additionally prenatally diagnosed, live-born infants did not undergo a procedure. Of the 56 procedures, 2 were by interventional catheterization, and 54 underwent a surgical repair. Prenatal detection for those undergoing a procedure statistically significantly increased over the 5 years from 38% to 82%, rho = 0.95 (p = .04).

CONCLUSIONS

Currently in Nevada, our prenatal detection rate is >80% in the general population for those between 0 and 6 months old who require a therapeutic procedure for aortic arch obstruction without intracardiac malformations.

Atresia of the Midportion of the Coronary Sinus: A Case Report

A 12-year-old with a history of critical pulmonary stenosis and moderate right ventricular hypoplasia underwent neonatal pulmonary valve dilation, an aortopulmonary shunt, and an infant cavopulmonary anastomosis with aortopulmonary shunt takedown. During a diagnostic cardiac catheterization at 12 years of age, angiography showed interruption in the midportion of the coronary sinus, which required no intervention.

Stage-1 Hybrid Palliation for High-Risk 2-Ventricle Patients with Ductal-Dependent Systemic Circulation in the Era of High Prenatal Detection

OBJECTIVE

We reviewed our center's prenatal detection and surgical experience with high-risk, 2-ventricle patients, with complex congenital heart disease that underwent stage-1 hybrid palliation.

METHODS

We retrospectively identified those born between March 2008 and March 2021 with 2-ventricle hearts, complex congenital cardiovascular malformations, and ductal-dependent systemic circulation that underwent stage-1 hybrid palliation consisting of surgical bilateral pulmonary artery banding and interventional catheterization placed ductus arteriosus stents.

RESULTS

We identified 30 patients. Of the 30, 19 (63%) were male. For the 30, median gestational age was 35 weeks (29-39 weeks), and median birth weight was 2.2 kg (0.6-4.5 kg). Of the 30, 1 was transferred from an adjacent state, and 29 were born in Nevada. Of the 29 born in Nevada, overall statewide prenatal detection was 18 of 29 (62%); however, for 2008 to 2011 the prenatal detection rate was 3 of 10 (30%) and 15 of 19 (79%) for 2012 to 2021, P = .03. For the last 5 years, prenatal detection for Nevada-born patients was 8 of 8 (100%). Two full-term newborns, without a prenatal diagnosis, presented postnatally in extremis. For the 30 patients, there were 0 stage-1 hybrid palliation mortalities, 1 subsequent repair mortality, and 3 late nonsurgical deaths.

CONCLUSIONS

Stage-1 hybrid palliation may result in excellent surgical outcomes for high-risk, 2-ventricle patients. Additionally, high rates of population-wide prenatal detection are possible for high-risk congenital heart disease, allowing prenatal planning and possibly reducing postnatal extremis presentations.

Common arterial trunk in the era of high prenatal detection rates: Results of neonatal palliation and primary repair

OBJECTIVE

We reviewed our center's experience with common arterial trunk.

METHODS

We included those with common arterial trunk in Nevada with estimated delivery dates or birth dates between June 2006 and May 2021. We excluded patients with functionally univentricular hearts.

RESULTS

We identified a total of 39: 32 prenatally and 7 postnatally. Of the 32 prenatally detected, 2 had elective termination, 2 had fetal demise, and 28 were live-born. Of the 7 postnatally diagnosed, 6 had prenatal care without a fetal echocardiogram, and 1 had no prenatal care. Overall, live-born prenatal detection was 28/34 (82%). Prenatal detection for 2006-2009 was 2/6 (33%) and for 2010-2021 was 26/28 (93%) p = .049. Of the 35 live-born infants, 1 died preoperatively, and 34 underwent neonatal surgery. Of the 34, 8 had palliation (birth weight 1.9±0.7 kg, range 0.8-2.6 kg), and 26 had a primary repair (birth weight 3.0±0.3 kg, range 2.6-4.0 kg) p = .0004. For all 34 neonatal surgical procedures, there were 2 (5.9%) deaths; however, there were no subsequent surgical or interventional catheterization mortalities.

CONCLUSIONS

In Nevada, current state-wide, general population prenatal detection of the common arterial trunk was more than 90%. By employing a combination of neonatal palliation and primary repair, surgical mortality was less than 6% in a cohort that included those with birth weights less than 2.5 kg, truncal valve surgery, and interrupted aortic arches.

Fontan-associated liver disease and total cavopulmonary anatomical flow effectors

OBJECTIVE

We investigated a relationship between a composite index comprised of Fontan-circuit anatomical features and hepatic fibrosis scores from biopsy.

METHODS

We identified living extracardiac Fontan patients, ≥7 years old and ≥5 but <20 years postoperative, that underwent cardiac catheterization and transvenous liver biopsy between March 2012 and September 2020. We divided patients into anatomical groups and applied a risk score to each patient. We compared average anatomical risk scores with average hepatic total fibrosis scores by group.

RESULTS

We identified 111 patients that met inclusion criteria. After excluding four patients, we assigned 107 to one of 12 anatomical variant groups (n ≥ 3). For the 107, the average age at liver biopsy was 14 ± 6 years old. Of the 107, 105 (98%) were New York Heart Association Class 1. We found average anatomical risk scores by group correlated with average total fibrosis scores by group (R = 0.8; p = .005). An average Fontan duration to biopsy of 10 ± 1 years was similar for all 12 anatomical groups. We found no other clinical variables, laboratory, or hemodynamic values that trended with anatomical risk scores or hepatic total fibrosis scores.

CONCLUSIONS

In a cohort of relatively young, stable extracardiac Fontan patients, average composite anatomical risk scores strongly correlated with average hepatic total fibrosis scores by anatomical group. These findings suggest that some anatomical variants in extracardiac Fontan patients are associated with higher Fontan-associated liver disease (FALD)-related hepatic total fibrosis scores than others, despite similar Fontan durations.

Fontan-Associated Anatomical Variants and Hepatic Fibrosis

OBJECTIVE

We hypothesized that a relationship between post-Fontan hepatic fibrosis and anatomical variants might exist.

METHODS

Attempting to limit confounding variables, we analyzed data from living, stable, post-extracardiac Fontan patients who underwent cardiac catheterization and transvenous hepatic biopsy procedures between March 2012 and June 2020.

RESULTS

We identified 120 patients who met the inclusion criteria. Of the 120, 35 (29%) had pulmonary artery stents. For the 35 with pulmonary artery stents, the average total fibrosis score was 3.2 ± 1.9 and the fibrosis progression rate was 0.36 ± 0.33, and for those with no pulmonary artery stents, the total fibrosis score was 2.6 ± 1.8 and the fibrosis progression rate was 0.27 ± 0.33 (P = .13 and P = .11, respectively). Of the 120, 65 had functional univentricles of right ventricular type. Of these 65, 27 had pulmonary artery stents. For the 27 with pulmonary artery stents, the average total fibrosis score was 3.4 ± 1.8 and the average fibrosis progression rate was 0.39 ± 0.30, and for the 38 without pulmonary artery stents, the average fibrosis score was 2.3 ± 1.5 and the average fibrosis progression rate was 0.23 ± 0.21 (P = .01 for comparison of both values).

CONCLUSIONS

This study's findings suggest that a post-extracardiac Fontan with a functional univentricle of right ventricular type plus a pulmonary artery stent may have more advanced liver pathology than those without a pulmonary artery stent at similar Fontan duration years and ages at liver biopsy.

“Crossed” pulmonary arteries in a newborn with truncus arteriosus: An unusual anatomic variant

We report a newborn with truncus arteriosus and a very unusual variant of “crossed” pulmonary arteries. The left pulmonary artery arose anterior and slightly to the right side of the common trunk and the right pulmonary artery arose from the posterior and left side of the common trunk. Computed tomographic images and a diagram are provided.

Hemodynamic and clinical effects of selexipag in children with pulmonary hypertension

Selexipag is an oral prostacyclin receptor agonist; it was recently approved for use in adults with pulmonary arterial hypertension. The safety and efficacy of selexipag has not yet been determined in the pediatric population. We describe short-term hemodynamic and clinical data with selexipag therapy in four pediatric patients with pulmonary hypertension. We reviewed clinical, echocardiographic, and hemodynamic data. One patient was transitioned from subcutaneous treprostinil to selexipag, and in three patients, selexipag was added as a third agent. Drug dosing was attained empirically based on patient body size. A follow-up catheterization was performed 12-18 months after initiation of selexipag therapy. All four patients tolerated selexipag well, without significant side effects. One patient transitioned successfully from subcutaneous treprostinil to selexipag. None of the four patients had clinical deterioration. In three patients who were able to perform a 6-minute walk test, pre and post selexipag distances were 350 and 400, 409 and 390, and 300 and 360 m, respectively. Echocardiograms showed no significant changes. Catheterization showed a variable change in pulmonary vascular resistance (small decrease in three patients and increase in one patient). Brain natriuretic peptide levels before and after selexipag in the four patients were 38 and 49, 33 and 54, 29 and 25, and 12 and 14 pg/mL, respectively. Selexipag use for 16-28 months was safe in four pediatric patients; none of them had clinical deterioration. Larger number of patients and longer follow-up intervals are necessary before further recommendations can be made.

Percutaneous retrieval of fractured intravascular catheters in premature infants

BACKGROUND

Premature infants often require long-term indwelling intravascular catheters. Occasionally, catheters fracture and migrate into cardiovascular structures, risking perforation, infection, thrombosis, and interference with cardiac and valve function. This case series describes our experience with percutaneous retrieval of broken intravascular catheters.

METHODS

A gooseneck micro-snare was used to retrieve fractured catheters in four premature infants, weighing between 840 and 1930 grams.

RESULTS

All procedures were successful without complications.

CONCLUSIONS

Gooseneck-snare retrieval of broken indwelling intravascular catheters can be performed safely and successfully in premature infants even those that weigh less than 1000 grams.

Detecting Critical Congenital Heart Disease in Nevada

Background:

We reviewed data on patients born with critical congenital heart disease in the state of Nevada and analyzed detection via prenatal diagnosis versus newborn pulse oximetry screening, location of birth, and gestational age at birth.

Methods:

We inquired our databases and electronic health records for all patients with critical congenital heart disease born in Nevada between January 2016 and May 2019.

Results:

We identified 218 live born patients. Of the 218, average gestational age was 38 weeks (±2.2 weeks). Of the 218, 171 (78%) were prenatally diagnosed, 37 (17%) were diagnosed by immediate postnatal signs and symptoms, 8 (4%) had false-negative pulse oximetry screens that resulted in post-hospital discharge presentations, and 2 (1%) had positive pulse oximetry screens. The eight post-hospital discharge presentations included four in extremis, two with extreme cyanosis, and two dying at home. Of the 171 prenatally diagnosed patients, 157 (92%) were born at the Nevada hospital with the congenital cardiac unit.

Conclusion:

To the best of our knowledge, our results represent the highest statewide, general population prenatal detection of critical congenital heart disease in the United States. Our high prenatal detection rate led to the majority of patients being born at the Nevada facility with the congenital heart unit, limiting intrastate neonatal transports. On average, patients were born at term. Further, in Nevada, state-mandated, universal pulse oximetry screening resulted in more false-negative results than positive results

An actuatable soft reservoir modulates host foreign body response

The performance of indwelling medical devices that depend on an interface with soft tissue is plagued by complex, unpredictable foreign body responses. Such devices-including breast implants, biosensors, and drug delivery devices-are often subject to a collection of biological host responses, including fibrosis, which can impair device functionality. This work describes a milliscale dynamic soft reservoir (DSR) that actively modulates the biomechanics of the biotic-abiotic interface by altering strain, fluid flow, and cellular activity in the peri-implant tissue. We performed cyclical actuation of the DSR in a preclinical rodent model. Evaluation of the resulting host response showed a significant reduction in fibrous capsule thickness (P = 0.0005) in the actuated DSR compared with non-actuated controls, whereas the collagen density and orientation were not changed. We also show a significant reduction in myofibroblasts (P = 0.0036) in the actuated group and propose that actuation-mediated strain reduces differentiation and proliferation of myofibroblasts and therefore extracellular matrix production. Computational models quantified the effect of actuation on the reservoir and surrounding fluid. By adding a porous membrane and a therapy reservoir to the DSR, we demonstrate that, with actuation, we could (i) increase transport of a therapy analog and (ii) enhance pharmacokinetics and time to functional effect of an inotropic agent. The dynamic reservoirs presented here may act as a versatile tool to further understand, and ultimately to ameliorate, the host response to implantable biomaterials.

Left Subclavian Artery Test Balloon Occlusion Before Covered Stent for Recoarctation and Aneurysm

A 57-year-old man, with a history of coarctation patch repair at three years of age, presented with left ventricular dilatation and moderate to severe dysfunction. A computed tomographic angiogram of the chest revealed moderate residual stenosis of the distal arch and proximal descending aorta and a large aneurysm adjacent to the origin of the left subclavian artery. Due to high surgical risk, a hybrid approach was undertaken with temporary balloon occlusion of the left subclavian artery, followed by surgical left common carotid to left subclavian artery graft and percutaneous covered stent implantation to relieve the obstruction and exclude the aneurysm.

Analysis of Screening Electrocardiogram for the Subcutaneous Defibrillator in Adults with Congenital Heart Disease

Candidates for the subcutaneous implantable cardioverter-defibrillator (S-ICD) are screened using an electrocardiogram (S-ECG) tool to measure appropriate detection. We sought to define the S-ICD candidacy of congenital heart disease patients using the S-ECG tool. We also analyzed the reliability of the (S-ECG) tool between measurers in this population. Patients above the age of 12 and with a diagnosis associated with either a higher incidence of cardiac arrest or vascular access challenges were asked to undergo screening. S-ECGs were then analyzed by a pediatric electrophysiologist, an S-ICD device engineer, and an S-ICD clinical representative for candidacy. Results were compared for interobserver variability and S-ECGs were analyzed by t test to determine variables that differ among passing and failing leads. Thirty-one patients underwent screening. Two of the 31 (6.5%) patients failed S-ICD screening. Analysis of the screening leads demonstrated the highest passing rates using lead III at a 5 mm/mV amplitude setting with 71 and 62% pass rate in the supine and standing positions, respectively. Interobserver analysis correlated well among the three measurers. There was a higher amplitude difference between QRS and T waves among passing versus failing S-ECG. Congenital heart disease patients have acceptable passage rates utilizing the S-ECG algorithm. Interobserver measurements were well correlated and these data suggest that the proximal coil to device (lead III) vector would be best utilized in this patient population. A larger difference between QRS and T wave amplitudes was associated with a higher S-ECG passing rate.

Assessment of microRNA and gene dysregulation in pulmonary hypertension by endoarterial biopsy

MicroRNAs (miRNAs) may regulate a number of genes, each of which may have a variety of functions. We utilized an endoarterial biopsy catheter to assess the dysregulation of miRNAs in a porcine shunt model of pulmonary hypertension (PH). Two Yucatan micropigs underwent surgical anastomosis of the left pulmonary artery to the descending aorta. Endoarterial biopsy samples were obtained at baseline, and at regular intervals during the progression of PH. RNA, isolated from biopsy samples, was analyzed by Illumina miRNA expression microarrays (containing ∼1200 human miRNAs), Affymetrix Porcine GeneChips, Bioconductor, and GeneSpring. We examined a total of 925 genes in a PH whole genome microarray. Biopsy samples showed that 39 miRNAs were downregulated and 34 miRNAs were upregulated compared to baseline. The number of PH-associated genes reported to be controlled by each of the dysregulated miRNAs was in the range of 1–113. The five miRNAs that had the largest number of PH-associated genes were: miR-548c-3p, miR-520d-3p, miR-130a-5p, miR-30a-3p, and miR-let-7g-3p. Several of the dysregulated miRNAs have been associated with molecular pathways and biologic processes involved in PH. Among 29 miRNAs, which were predicted to be dysregulated by a systems biology approach, we found four that were dysregulated in our porcine shunt model. An endoarterial biopsy technique was successful in showing that a large number of miRNAs are dysregulated in a porcine shunt model of PH. Many of these miRNAs control multiple PH-associated genes, molecular pathways, and biologic processes. Endoarterial biopsy offers potential experimental and clinical diagnostic value.

Challenges in the development of chronic pulmonary hypertension models in large animals

Pulmonary hypertension (PH) results in significant morbidity and mortality. Chronic PH animal models may advance the study of PH's mechanisms, evolution, and therapy. In this report, we describe the challenges and successes in developing three models of chronic PH in large animals: two models (one canine and one swine) utilized repeated infusions of ceramic microspheres into the pulmonary vascular bed, and the third model employed a surgical aorto-pulmonary shunt. In the canine model, seven dogs underwent microsphere infusions that resulted in progressive elevation of pulmonary arterial pressure over a few months. In this model, pulmonary endoarterial tissue was obtained for histology. In the aorto-pulmonary shunt swine model, 17 pigs developed systemic level pulmonary pressures after 2-3 months. In this model, pulmonary endoarterial tissue was sequentially obtained to assess for changes in gene and microRNA expression. In the swine microsphere infusion model, three pigs developed only a modest chronic increase in pulmonary arterial pressure, despite repeated infusions of microspheres (up to 40 in one animal). The main purpose of this model was for vasodilator testing, which was performed successfully immediately after acute microsphere infusions. Chronic PH in large animal models can be successfully created; however, a model's characteristics need to match the investigational goals.

Hybrid Palliation for Ductal-Dependent Systemic Circulation

We reviewed our hybrid palliation experience for 91 neonates, with ductal-dependent systemic circulation, born between August 2007 and October 2015. For analysis, we stratified the 91 patients by a risk factor (RF) score and divided them into three groups: (1) high-risk two-functional ventricles (2V) median RF score of 3 (N = 20); (2) low-risk one-functional ventricle (1V) RF score 0-1 (N = 32); and (3) high-risk 1V RF score ≥2 (N = 39). Midterm survival (median 4 years) by group was: (1) 95 %, (2) 91 %, and (3) 15 %, (p = 0.001). In conclusion, hybrid palliation was associated with excellent midterm results for high-risk 2V and low-risk 1V patients with ductal-dependent systemic circulation. In contrast, high-risk 1V patients had significantly worse outcomes.

Fontan Outcomes and Pulmonary Blood Flow at Birth

We previously noted, in a small group of post-Fontan patients, a possible association between hepatic fibrosis scores and the status of pulmonary blood flow at birth. To further explore this observation, we examined data from all Fontan patients seen in our center from July 2010 to March 2015. We identified 200 patients for analysis. Of the 200 patients, 56 underwent transvenous-hepatic biopsy. Of the 200 patients, 13 (6.5%) had protein-losing enteropathy. We divided both the 56 biopsy patients and the entire cohort of 200 patients into 4 groups: (1) unobstructed pulmonary blood flow at birth with functional left ventricles, (2) unobstructed pulmonary blood flow at birth with functional right ventricles, (3) obstructed pulmonary blood flow at birth with functional left ventricles, and (4) obstructed pulmonary blood flow at birth with functional right ventricles. Analysis of the 56 liver-biopsy patient groups showed median hepatic total-fibrosis scores for the 4 groups of 2 (0-6), 2 (0-8), 3 (2-6), and 4 (1-8), respectively, with statistical significance between groups 4 and 1 (p = 0.031). For the entire cohort of 200 patients, we analyzed the incidence of protein-losing enteropathy for each of the four groups and found protein-losing enteropathy percent occurrences of 0, 2.9, 8.8, and 16.1, respectively, with statistical significance between groups 4 and 2 (p = 0.031) and between groups 4 and 1 (p = 0.025). A history of obstructed pulmonary blood flow at birth, coupled with a functional right ventricle, may predict a poorer long-term Fontan outcome.

Eating disorder professionals' perceptions of oral health knowledge

OBJECTIVE

The aim of this study was to assess the oral health knowledge among professionals who specialize in treating eating disorders, and identify to what extent their education, and training addresses oral health care delivery, and recommendations for individuals with eating disorders.

METHOD

Participants for this study were licensed behavioural and medical providers specializing in eating disorder treatment (n = 107), and recruited through professional eating disorder organizations. Participants completed an anonymous, online questionnaire (33 items) assessing level of oral health-related education, knowledge and treatment recommendations within the participant's respective eating disorder discipline.

RESULTS

The majority of respondents (85%) were formally trained in eating disorders, and of those trained, 64.4% were not satisfied with the level of oral health education during formal education, and 19.5% report no oral health education. Respondents consider their knowledge of risk of oral disease for their clients/patients as average or above (84%), and ranked tooth erosion as the greatest reason for oral care (63%) while dry mouth led in the rankings for least significant reason for oral care (33%). Referral for oral care was found to be more common after reports of complication (55%).

DISCUSSION

According to these findings, eating disorder professionals regard oral health care for their clients as significant, and may be unaware of associated oral risk factors, current oral care standards and long-term oral effects of disordered eating apart from enamel erosion.

Fontan hepatic fibrosis and pulmonary vascular development

Fontan patients are at risk for hepatic fibrosis; however, risk factors are unclear. We performed a multivariate analysis in a small cohort of 14 patients (7-24 years old, mean 15) with Fontan circulation, undergoing cardiac catheterization and transvenous liver biopsies, all demonstrating fibrosis. We found by stepwise regression analysis that the history of pulmonary atresia was a predictor of higher total hepatic fibrosis scores than a history of unobstructed pulmonary blood flow (p = 0.002). Other variables including age, time from Fontan, hemodynamic measurements, and laboratory values were not predictive of total fibrosis scores at p values <0.05. Hepatic fibrosis scores between those born with pulmonary atresia versus unrestricted pulmonary blood flow may reflect differences in pulmonary circulatory physiology, resulting from differences in pulmonary vascular development.

Moving towards universal prenatal detection of critical congenital heart disease in southern Nevada: a community-wide program

This study compares the current, prenatal detection rate for critical congenital heart disease in Southern Nevada with the previously reported rate, after developing and expanding a comprehensive, community-wide fetal cardiology program. For the current-period analysis, we inquired our database and electronic health records for patients born in Clark County, Nevada, with critical congenital heart disease between May 2012 and April 2014, and we compared the results with the previous period between May 2003 and April 2006. The major components of the community-wide program include fetal congenital heart disease screening via general obstetric ultrasound studies performed in obstetrician's offices, radiology imaging centers, or maternal-fetal medicine specialty practices; subsequent referral for comprehensive fetal echocardiography performed in maternal-fetal medicine offices under the on-site supervision by fetal cardiologists; and recurring community educational programs teaching the 5-axial plane, fetal echocardiographic screening protocol to general obstetric sonographers and instructing perinatal sonographers in advanced imaging topics. For the current period, the prenatal detection rate for critical congenital heart disease in Southern Nevada was 71 versus 36% for the previous period (p < 0.001). The temporal improvement in prenatal detection of critical congenital heart disease may be related to our expanded decentralized, community-wide fetal cardiology program, and our experiences may be applicable to other metropolitan areas.

Evaluation of peak pressure gradients in patients after melody valve implantation: a comparison of cardiac catheterization and doppler echocardiography

OBJECTIVES

The aim of this study was to determine and quantify the relationship between Doppler echocardiography and cardiac catheterization measurements of the peak right ventricle-pulmonary artery (RV-PA) pressure gradient in patients within 24 hours of Melody valve implantation for treatment of a dysfunctional RV outflow tract (RVOT) conduit or bioprosthetic valve (BPV).

BACKGROUND

Patients with a dysfunctional RVOT conduit or BPV are now routinely treated percutaneously with implantation of a Melody valve. However, often the postimplantation catheter measurements of the RV-PA peak gradient do not match the postimplant echo-derived gradients obtained after completion of the procedure. Importantly, these echo gradients are commonly used to monitor patients after implantation over time.

METHODS

Medical records of 42 patients with Melody valve implantation were reviewed (men: 25/42; mean age: 22.4 ± 11.2 years; RVOT conduit: 23/42; BPV: 18/42; pulmonic stenosis: 6/42, pulmonic regurgitation: 3/42, both: 33/42).

RESULTS

The postimplantation RV-PA peak gradient measured by Doppler echocardiography (within 24 hours of valve implantation) was significantly higher than the measurements acquired by catheterization immediately following implantation (24.2 ± 16.3 mmHg vs. 11.6 ± 8.5 mmHg, P < 0.0001). The relationship showed a moderate-strong correlation (r = 0.65, P < 0.0001) with regression analysis suggesting a linear association in both directions (echo gradient = 1.24 × cath gradient + 9.8, P<0.0001 vs. cath gradient = 0.34 × echo gradient + 3.4, P<0.0001).

CONCLUSION

The Doppler echocardiography-derived RV-PA peak gradient within 24 hours of valve implantation is predictably higher than the catheter measured peak gradient immediately following valve implantation. A regression equation was derived to define this important relationship.

Transvenous hepatic biopsy in stable Fontan patients undergoing cardiac catheterization

Liver pathology complicates Fontan palliation. Previous reports established that both hepatic sinusoidal and portal fibrosis occur in patients after Fontan procedures. Past studies predominantly included symptomatic patient cohorts. Thus, the authors of this study aimed to characterize hepatic pathology via transvenous hepatic biopsies in 21 asymptomatic patients at the time of elective cardiac catheterization. Seven of these patients (33 %) were accompanied by an interventional procedure. Hepatic biopsies showed evidence of either sinusoidal or portal fibrosis or both in all but one patient. The findings showed a statistically significant (p = 0.005) moderately strong positive correlation between fibrosis scores and time since Fontan surgery. Additionally, no significant correlation was found between fibrosis scores and inferior vena cava pressure, pulmonary vascular resistance, platelet counts, or serum laboratory testing of hepatic function.

Vascular histomolecular analysis by sequential endoarterial biopsy in a shunt model of pulmonary hypertension

The molecular mechanisms of pulmonary arterial hypertension (PAH) remain ill-defined. The aims of this study were to obtain sequential endoarterial biopsy samples in a surgical porcine model of PAH and assess changes in histology and mRNA expression during the disease progression. Differentially expressed genes were then analyzed as potential pharmacological targets. Four Yucatan micro-pigs underwent surgical anastomosis of the left pulmonary artery to the descending aorta. Endovascular samples were obtained with a biopsy catheter at baseline (before surgery) and from the left lung 7, 60, and 180 days after surgery. RNA was isolated from biopsy samples, amplified and analyzed. Dysregulated genes were linked to drugs with potential to treat or prevent PAH. With the development of PAH in our model, we identified changes in histology and in the expression of several genes with known or investigational inhibitors and several novel genes for PAH. Gene dysregulation displayed time-related variations during disease progression. Endoarterial biopsy provides a new method of assessing pulmonary vascular histology and gene expression in PAH. This analysis could identify novel applications for existing and new PAH drugs. The detection of stage- and disease-specific variation in gene expression could lead to individualized therapies.

Successful immediate newborn ross-konno and mitral valve repair following fetal aortic valvuloplasty

Perinatal management of severe mitral regurgitation (MR) and aortic stenosis (AS) is difficult; mortality is high, and there are few reports of successful postnatal biventricular repairs. We report a patient with severe MR and AS, diagnosed prenatally, that underwent a fetal aortic valvuloplasty and a successful modified Ross-Konno procedure with concomitant mitral valve repair shortly after birth.

Hemodynamic and histologic characterization of a swine (Sus scrofa domestica) model of chronic pulmonary arterial hypertension

The purpose of this work was to develop and characterize an aortopulmonary shunt model of chronic pulmonary hypertension in swine and provide sequential hemodynamic, angiographic, and histologic data by using an experimental endoarterial biopsy catheter. Nine Yucatan female microswine (Sus scrofa domestica) underwent surgical anastomosis of the left pulmonary artery to the descending aorta. Sequential hemodynamic, angiographic, and pulmonary vascular samples were obtained. Six pigs (mean weight, 22.4±5.3 kg; mean age, 7.3±2.7 mo at surgery) survived long-term (6 mo) and consistently developed marked pulmonary arterial hypertension. Angiography showed characteristic central pulmonary arterial enlargement and peripheral tortuosity and pruning. The biopsy catheter was safe and effective in obtaining pulmonary endoarterial samples for histologic studies, which showed neointimal and medial changes. Autopsy confirmed severe pulmonary vascular changes, including concentric obstructive neointimal and plexiform-like lesions. This swine model showed hemodynamic, angiographic, and histologic characteristics of chronic pulmonary arterial hypertension that mimicked the arterial pulmonary hypertension of systemic-to-pulmonary arterial shunts in humans. Experimental data obtained using this and other models and application of an in vivo endoarterial biopsy technique may aid in understanding mechanisms and developing therapies for experimental and human pulmonary arterial hypertension.

Effectiveness and safety of balloon dilation of native aortic coarctation in premature neonates weighing < or = 2,500 grams

Six neonates weighing < or = 2,500 g with native coarctation of the aorta underwent balloon dilation. Of the 6 neonates, 4 were female and 2 were male, with a mean age of 14 days (range 9 to 20) and a mean weight of 1,900 g (range 790 to 2,500). The procedure was acutely successful in all 6 patients; the peak gradient decreased from 38 + or - 19 mm Hg to 11 + or - 3 mm Hg. The diameter increased from 1.5 + or - 0.6 mm to 3.6 + or - 0.7 mm. Of the 6 patients, 3 had required no additional intervention at a mean of 42 months after the initial dilation, and 3 had developed restenosis a mean of 2.4 months after the initial dilation and underwent successful redilation. Of the latter 3 patients, 2 developed restenosis and underwent surgical repair 37 and 68 days after the second dilation, and 1 of these patients developed recoarctation after surgery that was treated successfully with balloon dilation 54 days after the end-to-end repair. In conclusion, premature neonates weighing < or = 2,500 g with coarctation of the aorta appear to respond acutely to balloon dilation. Some patients will have a successful long-term result after a single balloon dilation procedure. However, restenosis is common and tends to develop rapidly.