Transcatheter Fontan Fenestration Closure: Sustained Improvements in Oxygen Saturation with Minimal Morbidity and Mortality.

Fontan fenestration decreases central venous pressure and preserves cardiac output while decreasing systemic oxygen saturation. Transcatheter fenestration closure increases oxygen saturation, though the persistence of this increase and the long-term incidence of adverse outcomes such as death and heart transplant remain unknown. We describe immediate and long-term clinical and adverse outcomes following fenestration closure. Catheterization, echocardiogram, and clinic reports were reviewed following transcatheter Fontan fenestration closure. Data were reported as n (%) and median (IQR). Continuous variables were compared using Wilcoxon ranked sum test. 51 patients had fenestration closure 0.9 (0.7-1.5) years following extracardiac Fontan operation. Most (84%) were closed with Amplatzer Septal Occluders. Systemic O2 saturation immediately increased from 87 (83-89) to 95 (94-97)%, P < 0.05. Cardiac index decreased from 4 (3-5) to 2.9 (2.6-3.5) L/min/m2. Fontan pressure and pulmonary vascular resistance were not significantly changed. Clinical follow-up duration for all patients was 7.3 (range 1.3-16) years. Oxygen saturation at last follow-up was 94.5 (92-97)% and did not decrease over time (P < 0.05). One patient (2%) developed protein losing enteropathy, 1 (2%) had heart transplant, and 1 (2%) patient died 9.4 years following fenestration closure. No patient required fenestration re-creation following closure. Transcatheter Fontan fenestration closure leads to sustained increases in systemic oxygen saturation and a low incidence of adverse outcomes such as death and transplant. Further study comparing fenestration closure to non-closure and longer follow-up duration are required to determine if there is a survival benefit to fenestration closure.

Physiological fetal vascular shunts and failure to regress: what the radiologist needs to know.

The fetal circulation is characterized by the presence of three physiological vascular shunts - the ductus arteriosus, the foramen ovale and the ductus venosus. Acting in concert, these shunts preferentially stream blood flow in a pattern that maximizes efficiency of blood oxygenation by the maternofetal unit. Shortly following the transition to extrauterine life, a quick and predetermined succession of events results in closure of these embryological structures with consequent establishment of postnatal vascular flow patterns. While this transition is often seamless, the physiological shunts of the fetus occasionally fail to regress. Such failure to regress can occur in isolation or in association with other congenital malformations. This failed regression challenges the circulatory physiology of the neonate and might have implications for the optimum functioning of several organ systems. When symptomatic, these shunts are treated. Interventions, when undertaken, might be medical, endovascular or surgical. The radiologist's role continues to expand in the assessment of these shunts, in providing a roadmap for treatment and in prompt identification of treatment-related complications. This review is to familiarize radiologists with the embryology, pre- and post-treatment imaging appearances, and associated complications of persistent fetal vascular shunts.

The incidence of recurrent laryngeal nerve injury resulting in vocal cord paralysis following interventional congenital catheterisation procedures.

BACKGROUND: Recurrent laryngeal nerve injury leading to vocal cord paralysis is a known complication of cardiothoracic surgery. Its occurrence during interventional catheterisation procedures has been documented in case reports, but there have been no studies to determine an incidence. OBJECTIVE: To establish the incidence of left recurrent laryngeal nerve injury leading to vocal cord paralysis after left pulmonary artery stenting, patent ductus arteriosus device closure and the combination of the procedures either consecutively or simultaneously. METHODS: Members of the Congenital Cardiovascular Interventional Study Consortium were asked to perform a retrospective analysis to identify cases of recurrent laryngeal nerve injury after the aforementioned procedures. Twelve institutions participated in the analysis. They also contributed the total number of each procedure performed at their respective institutions for statistical purposes. RESULTS: Of the 1337 patients who underwent left pulmonary artery stent placement, six patients (0.45%) had confirmed vocal cord paralysis. 4001 patients underwent patent ductus arteriosus device closure, and two patients (0.05%) developed left vocal cord paralysis. Patients who underwent both left pulmonary artery stent placement and patent ductus arteriosus device closure had the highest incidence of vocal cord paralysis which occurred in 4 of the 26 patients (15.4%). Overall, 92% of affected patients in our study population had resolution of symptoms. CONCLUSION: Recurrent laryngeal nerve injury is a rare complication of left pulmonary artery stent placement or patent ductus arteriosus device closure. However, the incidence is highest in patients undergoing both procedures either consecutively or simultaneously. Additional research is necessary to determine contributing factors that might reduce the risk of recurrent laryngeal nerve injury.

Long-Term Outcomes of Balloon Valvuloplasty for Isolated Pulmonary Valve Stenosis.

To evaluate the long-term cumulative incidence of ≥ moderate pulmonary regurgitation (PR) and re-intervention following balloon pulmonary valvuloplasty (BPV). While BPV for pulmonary valve stenosis (PS) relieves obstruction acutely, long-term outcomes are not well documented. Between 1982 and 2002, 211 patients had BPV for isolated PS. Follow-up data were available for 103 patients. Cumulative incidence of ≥ moderate PR and re-intervention was evaluated and risk factors for ≥ moderate PR assessed in univariate and multivariable analyses. Median age at BPV was 0.7 years (range 1 day-42.2 years); peak catheter gradient was 65 mmHg (range 31-169 mmHg); 23% had critical PS. Sixty-two patients had a recent echocardiogram with median follow-up 15.1 years (range 10.1-26.3 years); 60% had ≥ moderate PR. Three patients had pulmonary valve replacement following BPV due to symptomatic severe PR. In univariate analysis, critical PS, younger age, smaller BSA, and smaller pulmonary annulus at the time of BPV, as well as greater baseline PS gradient by catheterization, were associated with ≥ moderate PR (all p < 0.05). In multivariable analysis, only BSA < 0.3 m2 was independently associated with ≥ moderate PR (adjusted odds ratio 6.4, 95% confidence interval 1.2-33.6). In the largest study to date of > 10-year outcomes following BPV, 60% of patients with available follow-up data developed ≥ moderate PR. Few patients had pulmonary valve replacement. Patients with lower BSA at the time of BPV were more likely to have greater PR at late follow-up.

Results of coil closure of patent ductus arteriosus using a tapered tip catheter for enhanced control.

OBJECTIVES: This article describes the efficacy and embolization rates of coil delivery via modified vertebral catheter (MVC) for patent ductus arteriosus (PDA) closure. BACKGROUND: Various techniques have been devised to enhance coil control and prevent embolization during PDA closure. Since 1995, they have delivered coils via tapered vertebral catheters for improved coil control. METHODS: Catheterization reports, angiograms, and echocardiograms were reviewed for patients with PDA occlusion via MVC from 2001 to 2014. Residual shunting was determined by angiography and echocardiogram within 24 hr post-procedure. Procedural success was defined as ≤ trivial angiographic and echocardiographic shunt, and no aortic nor LPA obstruction, after final coil delivery. RESULTS: About 125 coil occlusions were attempted in 103 patients. Minimal PDA diameter was 2 (0.6-6) mm. Four coils were removed with a snare/bioptome due to aortic/LPA obstruction following release. Seven were malpositioned while still held by the MVC of which three embolized while attempting withdrawal. Five embolized after full release from the MVC. The embolization rate was 6.4%. Embolizations were more likely in PDAs ≥ 2.5 mm (P < 0.05). Ultimately, 98/103 PDAs were occluded using the MVC. No patient had greater trivial residual shunt or aortic/LPA obstruction for an overall success rate of 95%. For PDAs < 2.5 mm the success rate was 97%. CONCLUSIONS: Coil delivery via MVC was safe and effective for small PDAs. While fully controlled release and retrieval devices are now available for PDA closure with lower embolization rates, coil occlusion by MVC should still be considered for small PDAs, especially in resource limited regions. © 2016 Wiley Periodicals, Inc.

Transcatheter occlusion of large pulmonary arteriovenous malformations using multiple devices in a neonate.

Pulmonary arteriovenous malformations (PAVMs) are usually well-tolerated hemodynamically. Rarely, they cause severe neonatal cyanosis, requiring urgent treatment. We report the use of multiple transcatheter vascular occlusion devices to reduce right-to-left shunting in a neonate with multiple, large PAVMs.

Hemodynamic and Hematologic Effects of Histotripsy of Free-Flowing Blood: Implications for Ultrasound-Mediated Thrombolysis.

PURPOSE: To investigate the extent and consequences of histotripsy-induced hemolysis in vivo. MATERIALS AND METHODS: Porcine femoral venous blood was treated with histotripsy in 11 animals with systemic heparinization and 11 without heparin. Serum and hemodynamic measurements were obtained at 0, 2, 5, 10, 15, and 30 minutes and 48-72 hours after the procedure. Fisher exact test was used to determine differences in mortality between heparinized and nonheparinized groups. A linear mixed effects model was used to test for differences in blood analytes and hemodynamic variables over time. RESULTS: Of 11 animals in the nonheparinized group, 5 died during or immediately after histotripsy (45% nonheparin mortality vs 0% heparin mortality, P = .035). Serum hematocrit, free hemoglobin, lactate dehydrogenase (LDH), and right ventricular systolic pressure changed significantly (P < .001) over the treatment time. Serum hematocrit decreased slightly (from 32.5% ± 3.6% to 29.4% ± 4.2%), whereas increases were seen in free hemoglobin (from 6.2 mg/dL ± 4.6 to 348 mg/dL ± 100), LDH (from 365 U/L ± 67.8 ± to 722 U/L ± 84.7), and right ventricular systolic pressure (from 23.2 mm Hg ± 7.2 to 39.7 mm Hg ± 12.3). After 48-72 hours, hematocrit remained slightly decreased (P = .005), whereas LDH and free hemoglobin remained slightly increased compared with baseline (both P < .001). CONCLUSIONS: Intravascular histotripsy applied to free-flowing venous blood is safe with systemic heparinization, causing only transient hemodynamic and metabolic disturbances, supporting its use as a future noninvasive thrombolytic therapy modality.

Long-term outcomes up to 25 years following balloon pulmonary valvuloplasty: A multicenter study.

OBJECTIVE: Evaluate long-term outcomes following balloon pulmonary valvuloplasty (BPV) for pulmonary stenosis (PS). BACKGROUND: Long-term data following BPV is limited to small, single center studies. METHODS: BPV from April 12, 1985 to January 7, 2015 from three centers were included. Outcomes studied were ≥ moderate PI by echocardiogram and residual PS ≥ 40 mm Hg. Risk factors for ≥ moderate PI, residual PS, and repeat intervention were assessed by univariate and multivariate analysis. RESULTS: Among 254 patients, mean age at BPV was 3.8 years (range 1 day-67 years), initial PS catheter gradient was 56 mm Hg (IQR 40-70), 19% had critical PS, and 9% had genetic syndromes. Mean follow-up duration was 7.5 years (maximum 25 years). Sixty-nine (29%) had ≥ moderate PI, 41 patients (17%) had residual PS > 40 mm Hg, and 31 (13%) had re-intervention. In univariate analysis, younger age, lower weight, greater initial PS gradient, greater initial RV/systemic pressure ratio, critical PS, and longer follow-up duration were associated with ≥ moderate PI. Greater initial PS gradient was associated with long-term residual PS or repeat intervention. In multivariate analysis, greater initial gradient and lower weight were independently associated with > moderate PI and greater initial PS gradient and genetic abnormality were independently associated with residual PS and repeat intervention. CONCLUSION: Smaller patients with greater initial PS were more likely to develop significant long-term PI. Patients with greater initial PS and genetic abnormalities were more likely to have residual PS or require repeat intervention following BPV.

Protein Losing Enteropathy After Cardiac Transplantation Successfully Treated by Stent Implantation.

Protein losing enteropathy (PLE) is a severe consequence of Fontan physiology that sometimes requires heart transplantation for definitive treatment. We describe transplant refractory PLE in a patient with heterotaxia and complex systemic and hepatic venous connections, successfully treated by transcatheter relief of multiple venous obstructions.

A tale of two brothers: anomalous coronary arteries in two siblings.

We report a case of a 10-year-old boy with aberrant left coronary artery from the right sinus of Valsalva, whose presenting sign was cardiac arrest. The patient's asymptomatic younger brother was found to have aberrant right coronary artery from the left sinus of Valsalva. This is the first report of a familial clustering of coronary artery anomalies in which the initial presentation of one subject was sudden cardiac death and a sibling harboring a similar lesion was identified while asymptomatic.

Neuroanatomical substrates for paroxysmal dyskinesia in lethargic mice.

The paroxysmal dyskinesias are a group of neurological disorders described by intermittent attacks of involuntary abnormal movements superimposed on a relatively normal baseline. The neuroanatomical substrates for these attacks are not fully understood, though available evidence from studies of affected people and animal models points to dysfunction in the basal ganglia or cerebellum. In the current studies, the anatomical basis for paroxysmal dyskinesias in lethargic mice was determined via histochemical methods sensitive to changes in regional brain activity followed by surgical elimination of the suspected source. Cytochrome oxidase histochemistry revealed increased activity in the red nucleus. Surgical removal of the cerebellum worsened ataxia but eliminated paroxysmal dyskinesias. These studies support the hypothesis that abnormal cerebellar output contributes to paroxysmal dyskinesias.

Penetrance of mutations in plakophilin-2 among families with arrhythmogenic right ventricular dysplasia/cardiomyopathy.

OBJECTIVES: The purpose of our study was to characterize the penetrance of PKP2 mutations among family members of people with arrhythmogenic right ventricular dysplasia/cardiomyopathy (ARVD/C) and to examine clinical features and predictors of disease among PKP2 mutation carriers. BACKGROUND: Arrhythmogenic right ventricular dysplasia/cardiomyopathy is an inherited cardiomyopathy characterized by fatty-fibrous myocardial replacement of the right ventricle, ventricular arrhythmias, and right ventricular dysfunction. Mutations in PKP2, the gene encoding plakophilin-2, are found in 11% to 43% of ARVD/C probands. METHODS: The study population was composed of 64 individuals in 9 families with an ARVD/C proband previously shown to carry a pathogenic PKP2 mutation. The diagnosis of ARVD/C was established based on task force criteria (TFC) set by the European Society of Cardiology. RESULTS: In addition to the probands, PKP2 mutations were present in 52% of relatives screened. Forty-nine percent of PKP2 mutation carriers met TFC. Among mutation carriers who did not meet full TFC, 50% met at least some TFC criteria besides family history. Pedigrees showed wide intra-familial variability, ranging from severe disease with early death to individuals who were completely asymptomatic late in life. Male PKP2 mutation carriers were more likely to have structural and conduction abnormalities as determined by imaging studies, signal-averaged electrocardiography, and 24-h ambulatory electrocardiography (p < 0.05). CONCLUSIONS: PKP2 mutations in a group of North American families with ARVD/C have both reduced penetrance and variable expressivity. Gender may have an influence on penetrance of PKP2 mutations, with male mutation carriers more likely to develop specific phenotypic manifestations of this disease.