Outcomes and Predictors of Perinatal Mortality in Fetuses With Ebstein Anomaly or Tricuspid Valve Dysplasia in the Current Era: A Multicenter Study

BACKGROUND

Ebstein anomaly and tricuspid valve dysplasia are rare congenital tricuspid valve malformations associated with high perinatal mortality. The literature consists of small, single-center case series spanning several decades. We performed a multicenter study to assess the outcomes and factors associated with mortality after fetal diagnosis in the current era.

METHODS AND RESULTS

Fetuses diagnosed with Ebstein anomaly and tricuspid valve dysplasia from 2005 to 2011 were included from 23 centers. The primary outcome was perinatal mortality, defined as fetal demise or death before neonatal discharge. Of 243 fetuses diagnosed at a mean gestational age of 27±6 weeks, there were 11 lost to follow-up (5%), 15 terminations (6%), and 41 demises (17%). In the live-born cohort of 176 live-born patients, 56 (32%) died before discharge, yielding an overall perinatal mortality of 45%. Independent predictors of mortality at the time of diagnosis were gestational age <32 weeks (odds ratio, 8.6; 95% confidence interval, 3.5-21.0; P<0.001), tricuspid valve annulus diameter z-score (odds ratio, 1.3; 95% confidence interval, 1.1-1.5; P<0.001), pulmonary regurgitation (odds ratio, 2.9; 95% confidence interval, 1.4-6.2; P<0.001), and a pericardial effusion (odds ratio, 2.5; 95% confidence interval, 1.1-6.0; P=0.04). Nonsurvivors were more likely to have pulmonary regurgitation at any gestational age (61% versus 34%; P<0.001), and lower gestational age and weight at birth (35 versus 37 weeks; 2.5 versus 3.0 kg; both P<0.001).

CONCLUSION

In this large, contemporary series of fetuses with Ebstein anomaly and tricuspid valve dysplasia, perinatal mortality remained high. Fetuses with pulmonary regurgitation, indicating circular shunt physiology, are a high-risk cohort and may benefit from more innovative therapeutic approaches to improve survival.

Sequential percutaneous closure of mitral prosthetic paravalvular leak and complex communicating pseudoaneurysms of the ascending aorta and subvalvar left ventricular outflow tract

Ascending aortic and subvalvar left ventricular outflow tract (LVOT) pseudoaneurysms are rare complications following aortic valve or root replacement surgery. Clinically important paravalvular leaks are rare complications following any valve replacement surgery. We report an unusual case of sequential percutaneous closure of mitral prosthetic paravalvular leak and complex communicating ascending aortic and subvalvar LVOT pseudoaneurysms, which demonstrates the importance of multimodal imaging assessment surrounding percutaneous closure. © 2015 Wiley Periodicals, Inc.

Clinical and hemodynamic outcomes up to 7 years after transcatheter pulmonary valve replacement in the US melody valve investigational device exemption trial

BACKGROUND

Studies of transcatheter pulmonary valve (TPV) replacement with the Melody valve have demonstrated good short-term outcomes, but there are no published long-term follow-up data.

METHODS AND RESULTS

The US Investigational Device Exemption trial prospectively enrolled 171 pediatric and adult patients (median age, 19 years) with right ventricular outflow tract conduit obstruction or regurgitation. The 148 patients who received and were discharged with a TPV were followed up annually according to a standardized protocol. During a median follow-up of 4.5 years (range, 0.4-7 years), 32 patients underwent right ventricular outflow tract reintervention for obstruction (n=27, with stent fracture in 22), endocarditis (n=3, 2 with stenosis and 1 with pulmonary regurgitation), or right ventricular dysfunction (n=2). Eleven patients had the TPV explanted as an initial or second reintervention. Five-year freedom from reintervention and explantation was 76±4% and 92±3%, respectively. A conduit prestent and lower discharge right ventricular outflow tract gradient were associated with longer freedom from reintervention. In the 113 patients who were alive and reintervention free, the follow-up gradient (median, 4.5 years after implantation) was unchanged from early post-TPV replacement, and all but 1 patient had mild or less pulmonary regurgitation. Almost all patients were in New York Heart Association class I or II. More severely impaired baseline spirometry was associated with a lower likelihood of improvement in exercise function after TPV replacement.

CONCLUSIONS

TPV replacement with the Melody valve provided good hemodynamic and clinical outcomes up to 7 years after implantation. Primary valve failure was rare. The main cause of TPV dysfunction was stenosis related to stent fracture, which was uncommon once prestenting became more widely adopted.

CLINICAL TRIAL REGISTRATION

URL: http://www.clinicaltrials.gov. Unique identifier: NCT00740870.

Intermediate Outcomes in the Prospective, Multicenter Coarctation of the Aorta Stent Trial (COAST)

BACKGROUND

The Coarctation of the Aorta Stent Trial (COAST) was designed to assess the safety and efficacy of the Cheatham Platinum stent when used in children and adults with native or recurrent coarctation. Acute outcomes have been reported. We report here follow-up to 2 years.

METHODS AND RESULTS

A total of 105 patients underwent attempted implantation, with 104 successes. There were no procedural deaths, serious adverse events, or surgical intervention. All patients experienced immediate reduction in upper- to lower-extremity blood pressure difference with sustained improvement to 2 years. Rates of hypertension and medication use decreased from baseline to 12 months and remained largely unchanged at 2 years. Six aortic aneurysms have been identified: 5 were successfully treated with covered stent placement, and 1 resolved without intervention. Stent fractures were noted in 2 patients at 1 year and 11 patients at 2 years, with evidence of fracture progression. To date, only larger stent diameter was associated with stent fracture. Twelve additional fractures have occurred after 2 years. No fracture has resulted in loss of stent integrity, stent embolization, aortic wall injury, or reobstruction. Nine reinterventions occurred in the first 2 years for stent redilation and address of aneurysms, and 10 additional reinterventions occurred after 2 years.

CONCLUSIONS

The Cheatham Platinum stent is safe and associated with persistent relief of aortic obstruction. Stent fracture and progression of fracture occur but have not resulted in clinically important sequelae. Reintervention is common and related to early and late aortic wall injury and need for re-expansion of small-diameter stents.

CLINICAL TRIAL REGISTRATION

URL: http://www.clinicaltrials.gov. Unique identifier: NCT00552812.

Iatrogenic aortopulmonary communications after transcatheter interventions on the right ventricular outflow tract or pulmonary artery: Pathophysiologic, diagnostic, and management considerations

OBJECTIVES

To investigate the spectrum, etiology, and management of traumatic aortopulmonary (AP) communications after transcatheter interventions on the pulmonary circulation.

BACKGROUND

An iatrogenic AP communication is an unusual complication after balloon pulmonary artery (PA) angioplasty or stenting, or transcatheter pulmonary valve replacement (TPVR). However, with the increasing application of transcatheter therapies for postoperative PA stenosis and right ventricular outflow tract (RVOT) dysfunction, including percutaneous pulmonary valve replacement, consideration of the etiology, diagnosis, and management of this problem is important for interventional cardiologists performing such procedures.

METHODS AND RESULTS

We present three new cases, as well as gross anatomy and histopathology data, related to AP communications after PA interventions. We also review the literature relevant to this topic. Including these new cases, there have been 18 reported cases of iatrogenic AP communication after transcatheter interventions on the PAs or RVOT, primarily patients with transposition of the great arteries who underwent PA angioplasty after an arterial switch operation, or after TPVR in patients who had undergone a Ross procedure. The likely cause of such defects is PA trauma plus distortion of the neo-aortic anastomosis resulting from angioplasty or stenting of the RVOT or central PAs, with subsequent dissection through the extravascular connective tissue and into the closely adjacent vessel through the devitalized tissue at the anastomosis.

CONCLUSIONS

Cardiologists performing PA or RVOT interventions should be aware of the possibility of a traumatic AP communication and consider this diagnosis when confronted with suggestive signs and symptoms.

Low rate of prenatal diagnosis among neonates with critical aortic stenosis: insight into the natural history in utero

OBJECTIVES

To better understand the natural history and spectrum of fetal aortic stenosis (AS), we aimed to (1) determine the prenatal diagnosis rate of neonates with critical AS and a biventricular (BV) outcome, and (2) describe the findings at fetal echocardiography in patients diagnosed prenatally.

METHODS

A multicenter, retrospective study was performed on neonates who presented with critical AS and who were discharged with a BV outcome from 2000 to 2013. The prenatal diagnosis rate was compared with that reported for hypoplastic left heart syndrome (HLHS). We reviewed fetal echocardiographic findings in patients who were diagnosed prenatally.

RESULTS

In only 10 (8.5%) of 117 neonates with critical AS and a BV outcome was the diagnosis made prenatally, a rate significantly lower than that for HLHS in the contemporary era (82%; P < 0.0001). Of the 10 patients diagnosed prenatally, all had developed left ventricular dysfunction by a median gestational age of 33 (range, 28-35) weeks. When present, Doppler abnormalities such as retrograde flow in the aortic arch (n = 2), monophasic mitral inflow (n = 3) and left-to-right flow across the foramen ovale (n = 8) developed late in gestation (median 33 weeks).

CONCLUSION

The prenatal diagnosis rate of critical AS and a BV outcome among neonates is very low, probably owing to a relatively normal four-chamber view in mid-gestation with development of significant obstruction in the third trimester. The natural history contrasts with that of severe mid-gestation AS with evolving HLHS and suggests that the gestational timing of development of significant AS has an important impact on subsequent left-heart growth in utero.

Comparison of reported outcomes with percutaneous versus surgical closure of ruptured sinus of Valsalva aneurysm

Sinus of Valsalva aneurysm is a rare cardiac malformation that stems from incomplete fusion of the aortic media and the aortic valve annulus, a weakness that may result in rupture of the sinus, large left-to-right shunt, and severe congestive heart failure. Historically, this lesion has been repaired surgically, but percutaneous closure (PC) has emerged as a therapeutic intervention over the last 20 years. We review and contrast 34 studies detailing the PC approach with 16 studies on surgical closure (SC), together comprising a total of 877 patients who were treated for ruptured sinus of Valsalva aneurysm from 1956 to 2014. Both groups had similar sites of rupture, age distribution, and clinical symptoms at presentation. Selection bias ultimately prohibits a direct comparison between the 2 groups as patients who underwent SC often had worse aortic regurgitation and more complex associated lesions, including endocarditis, bicuspid aortic valve, tunnel-type fistulous connections, larger defect size, and multiple site of rupture. In conclusion, although SC is indicated and reserved for these more complicated patients, our review of previously published reports reveals that PC in patients who are too ill to undergo bypass, with mild or no aortic regurgitation and simple associated defects (muscular ventricular septal defects, secundum atrial septal defect, small patent ductus arteriosus), can be safe, effective, and practical.

Embolic myocardial infarction in a patient with a Fontan circulation

Coronary artery embolism is an uncommon cause of acute myocardial infarction (MI). We present a patient with pulmonary atresia and severe right heart hypoplasia who underwent a lateral tunnel Fontan procedure in childhood and presented with an acute ST-segment elevation MI at 19 years of age. In addition to the known risk of thrombotic complications associated with a Fontan circulation, potential predisposing factors to thromboembolism in this patient included a right ventricle to left anterior descending coronary connection and a Fontan baffle leak. The patient was treated with device closure of the baffle leak and anticoagulation. This is one of the first reports of an embolic MI in a patient with a Fontan circulation. The optimal method of reducing thromboembolic risk in this patient, and those with a Fontan circulation in general, is complicated and no consensus exists.

Computational simulations of flow dynamics and blood damage through a bileaflet mechanical heart valve scaled to pediatric size and flow

Despite pressing needs, there are currently no FDA approved prosthetic valves available for use in the pediatric population. This study is performed for predictive assessment of blood damage in bileaflet mechanical heart valves (BMHVs) with pediatric sizing and flow conditions. A model of an adult-sized 23 mm St. Jude Medical (SJM) Regent(™) valve is selected for use in simulations, which is scaled in size for a 5-year old child and 6-month old infant. A previously validated lattice-Boltzmann method (LBM) is used to simulate pulsatile flow with thousands of suspended platelets for cases of adult, child, and infant BMHV flows. Adult BMHV flows demonstrate more disorganized small-scale flow features, but pediatric flows are associated with higher fluid shear stresses. Platelet damage in the pediatric cases is higher than in adult flow, highlighting thrombus complication dangers of pediatric BMHV flows. This does not necessarily suggest clinically important differences in thromboembolic potential. Highly damaged platelets in pediatric flows are primarily found far downstream of the valve, as there is less flow recirculation in pediatric flows. In addition, damage levels are well below expected thresholds for platelet activation. The extent of differences here documented between the pediatric and adult cases is of concern, demanding particular attention when pediatric valves are designed and manufactured. However, the differences between the pediatric and adult cases are not such that development of pediatric sized valves is untenable. This study may push for eventual approval of prosthetic valves resized for the pediatric population. Further studies will be necessary to determine the validity and potential thrombotic and clinical implications of these findings.

Fetal aortic valvuloplasty for evolving hypoplastic left heart syndrome: postnatal outcomes of the first 100 patients

BACKGROUND

Fetal aortic valvuloplasty can be performed for severe midgestation aortic stenosis in an attempt to prevent progression to hypoplastic left heart syndrome (HLHS). A subset of patients has achieved a biventricular (BV) circulation after fetal aortic valvuloplasty. The postnatal outcomes and survival of the BV patients, in comparison with those managed as HLHS, have not been reported.

METHODS AND RESULTS

We included 100 patients who underwent fetal aortic valvuloplasty for severe midgestation aortic stenosis with evolving HLHS from March 2000 to January 2013. Patients were categorized based on postnatal management as BV or HLHS. Clinical records were reviewed. Eighty-eight fetuses were live-born, and 38 had a BV circulation (31 from birth, 7 converted after initial univentricular palliation). Left-sided structures, namely aortic and mitral valve sizes and left ventricular volume, were significantly larger in the BV group at the time of birth (P<0.01). After a median follow-up of 5.4 years, freedom from cardiac death among all BV patients was 96±4% at 5 years and 84±12% at 10 years, which was better than HLHS patients (log-rank P=0.04). There was no cardiac mortality in patients with a BV circulation from birth. All but 1 of the BV patients required postnatal intervention; 42% underwent aortic or mitral valve replacement. On the most recent echocardiogram, the median left ventricular end-diastolic volume z score was +1.7 (range, -1.3 to +8.2), and 80% had normal ejection fraction.

CONCLUSIONS

Short- and intermediate-term survival among patients who underwent fetal aortic valvuloplasty and achieved a BV circulation postnatally is encouraging. However, morbidity still exists, and ongoing assessment is warranted.

Cardiac screening in infants with infantile hemangiomas before propranolol treatment

There is no uniform pretreatment cardiac evaluation for infants treated with oral propranolol, which is now the drug of choice for hemangiomas of infancy requiring systemic medical intervention. The aim of this study was to report and evaluate the findings of pretreatment cardiac evaluation. Data were reviewed for patients evaluated by a single hemangioma specialist and a single pediatric cardiologist prior to initiation of propranolol for infantile hemangioma. Cardiac evaluation included a complete echocardiogram. From July 2009 through January 2013, 239 consecutive patients 12 months of age or younger (median 2.7 months) were screened. No patients had cardiac contraindications to propranolol. However, 50 patients (21%) had an abnormal echocardiogram: 39 atrial septal defects (5 associated with right heart enlargement), 6 ventricular septal defects, 2 patent ductus arteriosus, 1 aortic coarctation, 1 pulmonary valve stenosis, and 1 aberrant subclavian artery. Overall, 69 patients had an audible heart murmur, 44 of which were not associated with pathologic findings on echocardiogram. All patients with a ventricular septal defect and 16 of 39 with an atrial septal defect had a murmur. Two of seven patients with PHACE syndrome had cardiac anomalies. None of the findings precluded the use of propranolol. Assisted reproductive technologies were used in 18% of pregnancies, including in vitro fertilization in 12%. Cardiac contraindications to propranolol treatment are uncommon in patients with infantile hemangioma. However, anatomic abnormalities were more common than reported in the general population. Further study is necessary to determine whether there is a pathogenic relationship between cardiac defects and nonsyndromic infantile hemangioma.

Fontan pathway growth: a quantitative evaluation of lateral tunnel and extracardiac cavopulmonary connections using serial cardiac magnetic resonance

BACKGROUND

Typically, a Fontan connection is constructed as either a lateral tunnel (LT) pathway or an extracardiac (EC) conduit. The LT is formed partially by atrial wall and is assumed to have growth potential, but the extent and nature of LT pathway growth have not been well characterized. A quantitative analysis was performed to evaluate this issue.

METHODS

Retrospective serial cardiac magnetic resonance data were obtained for 16 LT and 9 EC patients at 2 time points (mean time between studies, 4.2 ± 1.6 years). Patient-specific anatomies and flows were reconstructed. Geometric parameters of Fontan pathway vessels and the descending aorta were quantified, normalized to body surface area (BSA), and compared between time points and Fontan pathway types.

RESULTS

Absolute LT pathway mean diameters increased over time for all but 2 patients; EC pathway size did not change (2.4 ± 2.2 mm vs 0.02 ± 2.1 mm, p < 0.05). Normalized LT and EC diameters decreased, while the size of the descending aorta increased proportionally to BSA. Growth of other cavopulmonary vessels varied. The patterns and extent of LT pathway growth were heterogeneous. Absolute flows for all vessels analyzed, except for the superior vena cava, proportionally to BSA.

CONCLUSIONS

Fontan pathway vessel diameter changes over time were not proportional to somatic growth but increases in pathway flows were; LT pathway diameter changes were highly variable. These factors may impact Fontan pathway resistance and hemodynamic efficiency. These findings provide further understanding of the different characteristics of LT and EC Fontan connections and set the stage for further investigation.

Isolated pulmonary artery arising from a duct: a single-center review of diagnostic and therapeutic strategies

OBJECTIVE

Isolated pulmonary artery of ductal origin (IPADO) is a rare disease with diverse presentations. Diagnostic and therapeutic approaches vary widely given the low incidence. Reporting additional cases may help inform medical decision making.

METHODS

We reviewed diagnostic data--including echocardiography, catheterization, and MRI--and outcomes for all patients with IPADO at our institution.

RESULTS

Thirty-seven patients who met inclusion criteria were identified. The mean age at diagnosis was 3 months (range, 1 day-45 years). In 11 patients, the duct supplying the IPADO was patent (ie, patent ductus arteriosis [PDA]); the duct had closed (ligamentum) in the other 26 patients. When performed, catheterization delineated the anatomy in 90% (100% if PDA) versus 54% with magnetic resonance imaging. Patients with a PDA were more likely to undergo intervention (100% vs 58%, P=.02) and had earlier first intervention (1 vs 20 months; P<.001). Patients diagnosed at age≤6 months were more likely to undergo intervention (86% vs 50%; P=.03) and unifocalization (81% vs 44%; P=.04), and had greater IPADO flow at follow-up (40% vs 14%; P<.001). Patients who underwent any intervention had greater IPADO flow than those without intervention (38% vs 0%).

CONCLUSIONS

Early IPADO diagnosis is important in long-term outcome. However, successful interventions can be performed on older patients. Diagnosis relies on angiography but magnetic resonance imaging may play an increasingly important role. Although initial intervention depends on individual factors, the ultimate goal should be early unifocalization.

Impact of transcatheter pulmonary valve replacement on biventricular strain and synchrony assessed by cardiac magnetic resonance feature tracking

BACKGROUND

Transcatheter pulmonary valve (TPV) replacement is an emerging therapy intended to restore pulmonary valve function in patients with right ventricular outflow tract conduit dysfunction; the impact of this technique on ventricular strain and synchrony is not known.

METHODS AND RESULTS

Cardiac magnetic resonance and ECG data acquired at 1 center as part of the US Melody TPV trial were analyzed. Biventricular strain and mechanical synchrony measurements were made based on short-axis and 4-chamber steady-state free precession images using feature tracking software. Post- versus pre-TPV replacement findings were compared for all patients (n=31) and subgroups with predominant pulmonary regurgitation (n=13) or stenosis (n=18). Most patients had tetralogy of Fallot (18/31). After TPV replacement, left ventricular (LV) circumferential strain increased for the whole cohort (P<0.001) and both subgroups (pulmonary regurgitation P=0.01; pulmonary stenosis P=0.02). LV longitudinal strain increased for the whole cohort (P=0.02) and pulmonary regurgitation subgroup (P=0.05); circumferential right ventricular strain increased for the pulmonary stenosis group only (P=0.05). LV longitudinal synchrony improved significantly in the pulmonary regurgitation group (maximum wall delay P=0.03; cross-correlation delay P=0.01). Electric measures of synchrony did not improve.

CONCLUSIONS

In patients with right ventricular outflow tract conduit dysfunction, TPV replacement is associated with improved global LV strain, as well as improved right ventricular strain and LV synchrony in subgroups. Given the associations between strain and synchrony and clinical outcomes, these findings support potential long-term benefits of TPV replacement.

Angioplasty of Obstructed Homograft Conduits in the Right Ventricular Outflow Tract With Ultra-Noncompliant Balloons

Background—

Angioplasty and stent placement in right ventricle-to-pulmonary artery (RV-PA) conduits have been shown to prolong the functional lifespan of a conduit. Safety and efficacy of angioplasty of obstructed RV-PA homografts using ultra-noncompliant (UNC) or ultrahigh-pressure balloons are unknown.

Methods and Results—

From 2004 to 2012, 70 patients underwent 76 procedures for angioplasty of RV-PA homografts with UNC Atlas balloons. The UNC group was compared with a partially contemporaneous control cohort of 81 patients who underwent 84 angioplasty procedures with conventional balloons. Acute hemodynamic changes after angioplasty of homografts with UNC balloons included significantly reduced RV:Ao pressure ratio ( P =0.02) and right ventricular outflow tract gradients ( P ≤0.001). Balloon waist resolution was more frequently achieved with UNC balloons ( P =0.04), and balloon rupture occurred less often ( P <0.001). Conduit tears of any severity occurred in 22% of patients overall and were more common in the UNC group ( P =0.001). Patients with any conduit tear had significantly greater reduction in their RV:Ao pressure ratio ( P <0.001) and right ventricular outflow tract gradient ( P =0.004) than those with no tear. There were 4 unconfined tears, all in the UNC group, with no acute decompensations or deaths and only 1 patient who required surgical management.

Conclusions—

RV-PA conduit tears are common in patients undergoing angioplasty, but clinically important tears, which only occurred during UNC angioplasty in this series, were uncommon. UNC balloons can be used to good effect with significant reduction in right ventricular outflow tract gradient and the RV:Ao ratio when compared with conventional balloons.

Ventricular strain in fetuses with aortic stenosis and evolving hypoplastic left heart syndrome before and after prenatal aortic valvuloplasty

OBJECTIVE

The impact of prenatal intervention on fetal cardiac function has not been well defined. We assessed standard ventricular function parameters and strain in fetuses with evolving hypoplastic left heart syndrome (HLHS) treated with fetal aortic valvuloplasty (fAVP).

METHODS

Fetuses with valvar aortic stenosis that underwent fAVP were studied. Echocardiographic images prior to intervention (Pre), within 1 week after fAVP (Post), and at the last prenatal follow-up examination (FU) were analyzed. Left ventricular (LV) circumferential (LVCS) and longitudinal strain (LVLS), right ventricular (RV) longitudinal strain (RVLS), and LV end-diastolic dimension Z-scores (LVIDD-Z) were documented and compared according to postnatal outcome.

RESULTS

Among 57 fetuses studied, the postnatal outcome was biventricular in 23 and univentricular in 34. Prior to fAVP, strain was <4 in most cases, regardless of outcome. Biventricular fetuses had higher LVCS and LVLS segmental strain than univentricular fetuses. Among fetuses with a biventricular outcome, LVCS and LVLS increased as LVIDD-Z decreased in late gestation, whereas LVCS and LVLS remained <4 in univentricular fetuses, although the LVIDD-Z decreased to <0 in all cases. Septal RVLS increased after fAVP in the biventricular but not the univentricular outcome group.

CONCLUSION

In utero aortic valve dilation appears to have a beneficial effect on both LV and RV function in some fetuses with evolving HLHS.

Heterogeneity of regional function and relation to ventricular morphology in patients with fontan circulation

The relation between underlying ventricular morphology and regional function in patients with Fontan circulation remains unclear. The aim of this study was to compare regional function and its heterogeneity in patients with tricuspid atresia (TA), biventricular apex-forming morphology (BiV), and controls. Nineteen patients (median age 12 years) with Fontan circulation who presented consecutively were prospectively enrolled and compared with age- and heart rate-matched controls. Most patients were in New York Heart Association class I (63%). Longitudinal systolic strain (S), systolic strain rate (SRsys), and early diastolic strain rate (SRdia) peaks were obtained from 6 ventricular segments, and a coefficient of variation by segment was calculated as a measure of regional heterogeneity. Systolic S, SRsys and SRdia peaks were decreased at the right and left lateral walls in both patient groups compared with controls (p ≤0.001 for all). Patients with TA had higher systolic S and SRsys in the middle of the right lateral wall than those with BiV morphology (p = 0.009 and p = 0.001, respectively). The mean coefficients of variation assessed by S and SRsys were similar in controls and patients with TA but lower in those with BiV than in controls and patients with TA (p <0.001 and p = 0.01, respectively). The mean coefficient of variation assessed by SRdia was greater only in patients with BiV than in controls (p = 0.001). In conclusion, patients with Fontan circulation have more heterogeneous systolic and early diastolic regional function than healthy control subjects, and patients with TA have better systolic regional function in the middle of the right lateral wall and less systolic heterogeneity than patients with BiV morphology.

Risk of coronary artery compression among patients referred for transcatheter pulmonary valve implantation: a multicenter experience

BACKGROUND

The Melody transcatheter pulmonary valve (TPV) was approved for implantation in obstructed right ventricular outflow tract conduits in 2010 after a multicenter trial demonstrating improvements in conduit obstruction, regurgitation, and right ventricular pressure. A recognized risk and contraindication to TPV implantation is the demonstration of coronary artery (CA) compression during balloon angioplasty or stent placement in the overlying conduit. This study is the first to characterize the risk of CA compression in this population.

METHODS AND RESULTS

From 2007 to 2012, 404 patients underwent 407 catheterizations for potential TPV implantation (median age, 18 years) at 4 centers. Three hundred forty-three patients (85%) underwent valve implantation. Twenty-one patients (5%) had evidence of CA compression with simultaneous right ventricular outflow tract angioplasty and CA angiography. Sixty-eight patients (17%) had abnormal CA anatomy. Fifteen of 21 (71%) patients with CA compression had abnormal CA anatomy. Eight patients with tetralogy of Fallot and 7 patients with transposition of the great arteries demonstrated compression. Of the 34 patients with tetralogy of Fallot and abnormal CA, 7 (21%) demonstrated CA compression.

CONCLUSIONS

CA compression following TPV implantation can be catastrophic. CA compression was observed in 5% of patients during test balloon angioplasty. No patients in this study developed clinically apparent CA compression after TPV implantation. CA compression was significantly associated with the presence of abnormal CA anatomy, especially in patients with tetralogy of Fallot or transposition of the great arteries. Preimplantation coronary angiography with simultaneous test angioplasty is an important step to evaluate for the presence of CA compression during TPV implantation.

Outcomes After Primary Transcatheter Therapy in Infants and Young Children With Severe Bilateral Peripheral Pulmonary Artery Stenosis

Background—

Angioplasty and stent implantation have become accepted therapies for isolated peripheral pulmonary stenosis, and have been shown to increase vessel diameter and reduce right ventricular (RV) pressure acutely in patients with pulmonary artery (PA) stenosis. The purpose of this study was to assess long-term outcomes after primary transcatheter therapy for peripheral pulmonary stenosis.

Methods and Results—

We studied 69 patients who underwent primary transcatheter intervention for severe isolated peripheral pulmonary stenosis at ≤5 years of age. Genetic/syndromic diagnoses included Williams syndrome (n=23), non-Williams familial arteriopathy (n=12), and Alagille syndrome (n=3). At the initial PA intervention, median RV:aortic pressure ratio decreased from 1.00 to 0.88 (median decrease, 0.18; P <0.001). Patients with a higher preintervention RV:aortic pressure ratio had a greater reduction ( P <0.001). During follow-up (median, 8.5 years), 10 patients died, 5 from complications of PA catheterization (all before 1998). Thirteen patients underwent surgical PA intervention, most within 1 year and along with repair of supravalvar aortic stenosis. Freedom from any PA reintervention was 38±6% at 1 year and 22±6% at 5 years. The median RV:aortic pressure ratio decreased from 1.0 at baseline to 0.53 at the most recent catheterization ( P <0.001), and 82% of patients with available clinical follow-up were asymptomatic.

Conclusions—

Transcatheter therapy for infants with severe peripheral pulmonary stenosis has become safer, regardless of genetic condition. Coupled with reintervention and surgical relief in selected cases, RV:aortic pressure ratios decrease substantially and most patients are asymptomatic at late follow-up.

Risk factors for profuse systemic-to-pulmonary artery collateral burden in hypoplastic left heart syndrome

Risk factors for developing systemic-to-pulmonary artery collaterals (SPCs) in hypoplastic left heart syndrome (HLHS) are unknown. We performed a retrospective case-control study to identify risk factors for developing a profuse SPC burden in HLHS. Angiograms of 439 patients with HLHS (performed <2 years of age) were reviewed using a previously published angiographic grading scale to identify cases (profuse SPC burden, n = 20) and controls (no or minimal SPC burden, n = 35). In univariate analyses, profuse SPC burden was associated with mitral atresia and aortic atresia subtype (MA/AA) (65% vs 14%, p <0.0001), use of a Sano shunt (70% vs 37%, p = 0.03), longer log-transformed durations of intensive care unit stay (p = 0.02), hospital stay (p = 0.002), pleural drainage (p = 0.008) after stage 1 palliation, lower oxygen saturation at discharge after stage 1 palliation (82 ± 4 vs 85 ± 4%, p = 0.03), and a history of severe shunt obstruction (37% vs 11%, p = 0.04). In a multivariate logistic regression model, profuse SPC burden was associated with MA/AA subtype (odds ratio 6.6), Sano shunt type (odds ratio 8.6), and log-transformed duration of hospital stay after stage 1 (odds ratio 7.9, model p <0.0001, area under the curve 0.88). Nonassociated parameters included fetal aortic valve dilation, severe cyanotic episodes, number of days with open sternum or number of additional exploratory thoracotomies after stage 1 palliation, pulmonary vein stenosis, and restrictive atrial septal defect. In conclusion, in the present case-control study of patients with HLHS, the development of a profuse SPC burden was associated with MA/AA subtype, Sano shunt type, and longer duration of hospital stay after stage 1 palliation.

The Melody® valve and Ensemble® delivery system for transcatheter pulmonary valve replacement

The Melody® transcatheter pulmonary valve (TPV) is a percutaneous valve system designed for the treatment of obstruction and/or regurgitation of prosthetic conduits placed between the right ventricle and pulmonary arteries in patients with congenital heart disease. In 2000, Melody TPV became the first transcatheter valve implanted in a human; in 2006 it became the first transcatheter valve commercially available anywhere in the world; and in 2010 it was launched as the first commercially available transcatheter valve in the United States. In this review, we present the clinical background against which the Melody valve was developed and implemented, introduce the rationale for and challenges of transcatheter valve technology for this population, outline the history and technical details of its development and use, and summarize currently available data concerning the performance of the device.

Infective endocarditis after transcatheter pulmonary valve replacement using the Melody valve: combined results of 3 prospective North American and European studies

BACKGROUND

Transcatheter (percutaneous) pulmonary valve (TPV) replacement has emerged as a viable therapy for right ventricular outflow tract conduit dysfunction. Little is known about the incidence, clinical course, and outcome of infective endocarditis (IE) after TPV implant. We reviewed combined data from 3 ongoing prospective multicenter trials to evaluate the experience with IE among patients undergoing TPV replacement using the Melody valve.

METHODS AND RESULTS

Any clinical episode reported by investigators as IE with documented positive blood cultures and fever, regardless of TPV involvement, was considered IE. Cases were classified as TPV-related if there was evidence of vegetations on or new dysfunction of the TPV. The 3 trials included 311 patients followed for 687.1 patient-years (median, 2.5 years). Sixteen patients were diagnosed with IE 50 days to 4.7 years after TPV implant (median, 1.3 years), including 6 who met criteria for TPV-related IE: 3 with vegetations, 2 with TPV dysfunction, and 1 with both. The annualized rate of a first episode of IE was 2.4% per patient-year and of TPV-related IE was 0.88% per patient-year. Freedom from TPV-related IE was 97±1% 4 years after implant. All patients were treated with intravenous antibiotics, 4 had the valve explanted, and 2 received a second TPV. There was 1 sepsis-related death, 1 patient died of sudden hemoptysis, and 2 patients developed recurrent IE.

CONCLUSIONS

Bacterial endocarditis has occurred in all 3 prospective multicenter studies of the Melody valve in North America and Europe. Most cases did not involve the TPV and responded to antibiotics. More data are necessary to understand risk factors in this population.

Transcatheter Closure of Post-myocardial Infarction Ventricular Septal Rupture

Background—

Ventricular septal rupture (VSR) after acute myocardial infarction (AMI) is a potentially lethal mechanical complication of acute coronary syndromes. Given high surgical mortality, transcatheter closure has emerged as a potential strategy in selected cases. We report our single-center experience with double-umbrella device percutaneous closure of post-AMI VSR.

Methods and Results—

In this single-center, retrospective, cohort study, patients who underwent transcatheter closure of post-AMI VSR between 1988 and 2008 at Boston Children’s Hospital were included. Data were analysed according to whether the patients underwent direct percutaneous VSR closure or closure of a residual VSR after a previous surgical approach. Primary outcome was mortality rate at 30 days. Clinical predictors of primary outcome were investigated using univariate logistic regression. Thirty patients were included in the study (mean age, 67±8 years). A total of 40 closure devices were implanted. Major periprocedural complications occurred in 4 (13%) patients. Cardiogenic shock, increasing pulmonary/systemic flow ratio, and the use of the new generation (6-arm) STARFlex device all were associated with higher risk of mortality. The Model for End-Stage Liver Disease Excluding international normalized ratio (MELD-XI) score at the time of VSR closure seemed to be most strongly associated with death (odds ratio, 1.6; confidence interval, 1.1–2.2; P <0.001).

Conclusions—

Transcatheter closure of post-AMI VSR using CardioSEAL or STARFlex devices is feasible and effective. The MELD-XI score, a marker of multiorgan dysfunction, is a promising risk stratifier in this population of patients. Early closure of post-AMI VSR is advisable before establishment of multiorgan failure.

Left ventricular diastolic function in children and young adults with congenital aortic valve disease

Young patients with congenital aortic valve disease are at risk of left ventricular (LV) diastolic dysfunction (DD). We evaluated LV remodeling and the prevalence of, and risk factors for, DD in patients with aortic stenosis (AS), pure aortic regurgitation (AR), and AS+AR. Patients aged 8 to 39 years with congenital AS (n = 103), AR (n = 36), or AS+AR (n = 107) were identified. Cross-sectional assessment of the LV remodeling pattern and diastolic function was performed. A diastolic function score (DFS; range 0 to 4) was assigned to each patient, with 1 point for an abnormal value in each of 4 categories: mitral inflow (E/A and E-wave deceleration time), tissue Doppler E', E/E', and left atrial volume. Patients with a DFS of ≥2 were compared to those with a DFS <2. Concentric hypertrophy was the most common remodeling pattern in those with AS (51%), mixed/physiologic hypertrophy in those with AS+AR (48%) and eccentric hypertrophy in those with AR (49%) predominated. In the entire cohort, 91 patients (37%) had a DFS of ≥2. Patients with AS or AS+AR had greater DFS than those with pure AR (p <0.001). On multivariate analysis, a greater LV mass z-score and previous aortic valve balloon dilation were associated with a DFS of ≥2. In patients with catheterization data (n = 65), E/E' correlated with LV end-diastolic pressure. Those with a DFS of ≥2 had a greater LV end-diastolic pressure and mean pulmonary artery pressure than those with a DFS <2. In conclusion, DD is common in young patients with AS and AS+AR but not in those with pure AR. A greater LV mass and previous aortic valve dilation were associated with DD.

Melody valve implant within failed bioprosthetic valves in the pulmonary position: a multicenter experience

BACKGROUND

Transcatheter pulmonary valve implantation using the Melody valve has emerged as an important therapy for the treatment of postoperative right ventricular outflow tract dysfunction. Melody-in-bioprosthetic valves (BPV) is currently considered an off-label indication. We review the combined experience with transcatheter pulmonary valve implantation within BPVs from 8 centers in the United States and discuss technical aspects of the Melody-in-BPV procedure.

METHODS AND RESULTS

A total of 104 patients underwent Melody-in-BPV in the pulmonary position at 8 US centers from April 2007 to January 2012. Ten different types of BPVs were intervened on, with Melody valve implantation at the intended site in all patients. Following Melody valve implant, the peak right ventricle-to-pulmonary artery gradient decreased from 38.7 ± 16.3 to 10.9 ± 6.7 mm Hg (P<0.001), and the right ventricular systolic pressure fell from 71.6 ± 21.7 to 46.7 ± 15.9 mm Hg (P<0.001). There was no serious procedural morbidity, and no deaths related to the catheterization or implant. At a median follow-up of 12 months (1-46 months), no patients had more than mild regurgitation, and 4 had a mean right ventricular outflow tract gradient ≥30 mm Hg. During follow-up, there were 2 stent fractures, 3 cases of endocarditis (2 managed with surgical explant), and 2 deaths that were unrelated to the Melody valve.

CONCLUSIONS

Transcatheter pulmonary valve implantation using the Melody valve within BPVs can be accomplished with a high rate of success, low procedure-related morbidity and mortality, and excellent short-term results. The findings of this preliminary multicenter experience suggest that the Melody valve is an effective transcatheter treatment option for failed BPVs.

Exercise stress echocardiographic assessment of outflow tract and ventricular function in patients with an obstructed right ventricular-to-pulmonary artery conduit after repair of conotruncal heart defects

This study assessed right ventricular (RV) and RV outflow tract (RVOT) function and pressure in response to exercise in patients with an obstructed RV-pulmonary artery (PA) conduit using exercise stress echocardiography (ESE) to evaluate these parameters. RV-PA conduits inevitably develop stenosis and/or regurgitation over time. Assessment of conduit obstruction only at rest may not reveal the extent of physiologic perturbation related to RV pressure loading. Patients with a stenotic RV-PA conduit who were being considered for transcatheter pulmonary valve placement were approached prospectively. ESE was performed and ventricular images were obtained at rest and at peak exercise. Forty patients (median age 17 years) were enrolled. Most patients had tetralogy of Fallot (63%) and were in New York Heart Association class II (59%). Exercise stress echocardiographic images were adequate in 38 patients (95%). With exercise there was a significant increase in maximum instantaneous RVOT gradient from rest (59 vs 96 mm Hg, p <0.001); exercise-induced change in RVOT gradient correlated with global RV strain at rest (r = -0.3, p = 0.05). Compared to measurements at rest there were significant increases in median peak longitudinal strain of the left ventricular free wall, interventricular septum, and global left ventricular strain at peak exercise. There were no significant changes in median RV strain at peak exercise (RV free wall -14.3 [-26, -8] at rest vs -15.2 [-27, -3] at peak exercise, p = 0.87; global RV strain -13.9 [-32, -9] vs -15.1 [-23, -6], p = 0.11). In conclusion, using ESE it was possible to evaluate abnormal ventricular function and conduit dysfunction at peak exercise in patients with an obstructed RV-PA conduit.

Wire-related pulmonary artery injury during pediatric and adult congenital interventional cardiac catheterization

OBJECTIVES

Guidewires used in pediatric catheterization are typically floppy, soft, or J-tipped, and are generally assumed to be atraumatic. A recent sentinel case suggested that such wires may cause clinically significant pulmonary artery (PA) injury. We sought to determine the incidence of wire-related PA injury as a cause of "idiopathic" airway bleeding (endobronchial blood) during interventional cardiac catheterization in patients with congenital heart disease.

DESIGN

The Children's Hospital Boston database of cardiac catheterizations was reviewed for adverse events (AEs) indicating possible PA injury occurring between September 2006 and August 2011. Procedure notes were reviewed, and when the clinical scenario was suggestive of wire injury or was not clear, relevant angiograms were reviewed.

RESULTS

One thousand forty-seven cases involving PA dilation were performed in the period of interest. Five cases of probable wire injury were identified, suggesting an incidence of approximately 0.5 per 100 cases. Of these five cases, trauma was judged due to floppy-tipped wires in two, soft-tipped wires in two, and a J-tipped wire in one. In three cases, the distal wire was looped such that the leading segment was stiffer than the wire tip. Clinical manifestations of wire injury comprised contrast within the airway, vessel aneurysm/tear, obstructive intimal flap, blood from the endotracheal tube, hemothorax, and wedge defect on lung scan. These injuries were relatively benign and did not result in instability or prolonged bleeding.

CONCLUSIONS

Wire injury to the PAs is relatively uncommon, although possible with even floppy-tipped wires. The mechanism and implications of such injuries are markedly different than balloon-mediated vascular tears.

Echocardiographic predictors of left ventricular dysfunction after aortic valve surgery in children with chronic aortic regurgitation

OBJECTIVE

Postoperative left ventricular dysfunction is associated with poor prognosis in adults with severe chronic aortic regurgitation and published practice guidelines aim to minimize this risk. However, only limited information exists in pediatrics. The goal of this study was to define preoperative risk factors for postoperative left ventricular dysfunction in children with chronic aortic regurgitation.

METHODS

Patients fulfilling the following criteria were included in this study: (1) age at preoperative echocardiogram ≤18 years; (2) ≥moderate aortic regurgitation; (3) ≤mild aortic valve stenosis; (4) no additional valve disease/shunt; (5) underwent aortic valve surgery for aortic regurgitation; and (6) available preoperative and ≥6-month postoperative echocardiograms with adequate information. Primary outcome was postoperative left ventricular dysfunction defined as ejection fraction z-score < -2.

RESULTS

Median ages at diagnosis and surgery of the 53 eligible patients were 6.9 (0.04-17.2) and 13 years (1.2-22.4), respectively. Compared with patients whose postoperative left ventricular ejection fraction was normal, those with left ventricular ejection fraction z-score < -2 (n = 10) had significantly higher preoperative left ventricular end-diastolic and systolic volumes and dimensions and lower indices of systolic function. Preoperative left ventricular ejection fraction z-score < -1 was the most sensitive (89%; confidence interval [CI] 52, 100) but least specific (58%; CI 41, 73), whereas left ventricular end-systolic diameter z-score ≥ 5 was the most specific (95%; CI 84, 99) but least sensitive (60%; CI 26, 88) outcome identifier. A combination of shortening fraction z-score < -1 or end-systolic diameter z-score ≥ 5 best identified postoperative left ventricular dysfunction with an area of 0.819 under the receiver-operator characteristic curve.

CONCLUSION

Lower indices of left ventricular systolic function and severity of dilation identify children at risk for postoperative left ventricular dysfunction after aortic valve surgery. These identifiers are similar to predictors defined in adult patients albeit with different threshold values.

Outcomes of transcatheter approach for initial treatment of pulmonary atresia with intact ventricular septum

OBJECTIVE

To review the short and medium term outcome of transcatheter pulmonary valve perforation (PVP) in patients with pulmonary atresia-intact ventricular septum and non-right ventricular dependant coronary circulation (PA/IVS non-RVDCC).

BACKGROUND

PVP in patients with PA/IVS non-RVDCC has become more common in the past two decades. However, data on outcomes with this strategy are mixed.

METHODS

Data were reviewed retrospectively for all patients with PA/IVS non-RVDCC treated from 1996- 2010 at our institution. Patients who had severe neonatal Ebstein malformation, or initial interventional management at another institution were excluded.

RESULTS

PVP was attempted in 30 of 50 patients (60%); 26 (87%) of these had a successful procedure. Twenty-four patients (48%) had surgery without PVP. There were no deaths in the cohort. Complications of PVP included 5 (17%) myocardial perforations. Of those with successful PVP, 10 (38%) did not have surgery (PVP-NS) and 16 (62%) had surgery (PVP-S) prior to discharge. Tricuspid valve (TV) Z-score was larger in the PVP-NS than in PVP-S patients, with median TV diameter Z-scores of +0.7 (-0.9, 1.7) and -1.1 (-2.8, 2), respectively (P = 0.01). Time from PVP to either hospital discharge (PVP-NS group) or surgery (PVP-S group) was significantly different between groups: 15 (7, 22) and 8 days (0, 46), respectively (P = 0.01). There were no differences in the number of trials or lowest arterial PaO2 off prostaglandins between groups. All patients in the PVP-NS group had a biventricular circulation at a median follow-up of 4.3 years.

CONCLUSIONS

The results of a collaborative approach to treating neonates with PA/IVS non-RVDCC are excellent. Smaller TV size is associated with greater likelihood of surgery prior to discharge, and may serve as a surrogate for early RV inadequacy.

Staged left ventricular recruitment after single-ventricle palliation in patients with borderline left heart hypoplasia

OBJECTIVES

The goal of this study was to review results of a novel management strategy intended to rehabilitate the left heart (LH) in patients with LH hypoplasia who have undergone single-ventricle palliation (SVP).

BACKGROUND

Management of patients with hypoplastic LH syndrome and borderline left ventricle (LV) involves 2 options: SVP or biventricular repair. We hypothesized that staged LV recruitment and biventricular conversion may be achieved after SVP by using a strategy consisting of relief of inflow and outflow tract obstructions, resection of endocardial fibroelastosis, and promotion of flow through the LV.

METHODS

Patients with hypoplastic LH and borderline LV who underwent traditional SVP (n = 34) or staged LV recruitment (n = 34) between 1995 and 2010 were retrospectively analyzed and compared with a control SVP group.

RESULTS

Mean initial z-scores for LH structures before stage 1 SVP were not significantly different between groups. Mortality occurred in 4 of 34 patients after LV recruitment and in 7 of 34 after traditional SVP. LH dimension z-scores increased significantly over time after LV recruitment, whereas they declined after traditional SVP, with significant interaction between stage of palliation and treatment group. Restriction of the atrial septum (conducted in 19 of 34 patients) was the only predictor of increase in left ventricular end-diastolic volume (p < 0.001). Native biventricular circulation was achieved in 12 patients after staged LV recruitment; all of these patients had restriction at the atrial septum.

CONCLUSIONS

In these patients with borderline LH disease who underwent SVP, it is possible to increase LH dimensions by using an LV recruitment strategy. In a subset of patients, this strategy allowed establishment of biventricular circulation.

Evaluating the role of connexin43 in congenital heart disease: Screening for mutations in patients with outflow tract anomalies and the analysis of knock-in mouse models

Background:

GJA1 gene encodes a gap junction protein known as connexin 43 (Cx43). Cx43 is abundantly expressed in the ventricular myocardium and in cardiac neural crest cells. Cx43 is proposed to play an important role in human congenital heart disease, as GJA1 knock-out mice die neonatally from outflow tract obstruction. In addition, patients with visceroatrial heterotaxia or hypoplastic left heart syndrome were reported to have point mutations in GJA1 at residues that affect protein kinase phosphorylation and gating of the gap junction channel. However, as these clinical findings were not replicated in subsequent studies, the question remains about the contribution of GJA1 mutations in human congenital heart disease (CHD).

Materials and Methods:

We analyzed the GJA1 coding sequence in 300 patients with CHD from two clinical centers, focusing on outflow tract anomalies. This included 152 with Tetralogy of Fallot from over 200 patients exhibiting outflow tract anomalies, as well as other structural heart defects including atrioventricular septal defects and other valvar anomalies. Our sequencing analysis revealed only two silent nucleotide substitutions in 8 patients. To further assess the possible role of Cx43 in CHD, we also generated two knock-in mouse models with point mutations at serine residues subject to protein kinase C or casein kinase phosphorylation, sites that are known to regulate gating and trafficking of Cx43, respectively.

Results:

Both heterozygous and homozygous knock-in mice were long term viable and did not exhibit overt CHD.

Conclusion:

The combined clinical and knock-in mouse mutant studies indicate GJA1 mutation is not likely a major contributor to CHD, especially those involving outflow tract anomalies.