Comparison of Semi-Automated Versus Manual Quantitative Right Ventricular Assessment in Hypoplastic Left Heart Syndrome.

Quantitative echocardiographic evaluation is important for systemic right ventricles, but its asymmetric shape makes this challenging and time consuming when performed manually. Semi-automated software could make these quantitative measures easier to accomplish in the clinical setting. We hypothesized that semi-automated software would approximate manual measures of right ventricular size and function. Children with hypoplastic left heart who had echocardiograms were prospectively identified. These measurements were performed using manual and semi-automated techniques: end-diastolic and end-systolic area, fractional area change (FAC), dimensions (longitudinal, basal and mid-cavitary diameters), and tricuspid annular plane systolic excursion (TAPSE). Agreement between measures was evaluated. Sixty-three echocardiograms were analyzed. Intra- and inter-observer reliability was acceptable and similar between methods except that inter-observer reliability for the manual method was superior for TAPSE. Correlation between methods was high (r > 0.9, p < 0.001) for most of the measures. Correlation for FAC was r = 0.79, and for TAPSE the correlation was r = 0.61 (both p < 0.001). The percent relative difference between manual and semi-automated methods was less than 6% for most measures. End-systolic area and FAC had a relative difference of 10% and 11% respectively. The only measure with substantial bias between the manual and semi-automated methods was TAPSE which had a relative difference of 52%. EchoInsight® semi-automated software provides similar measures of right ventricular dimensions and FAC in patients with hypoplastic left heart compared to manual measures. Measures of TAPSE do not correlate well between manual and semi-automated methods. Further research is warranted on the use of semi-automated analyses in this patient population.

Added Value of Live 3-Dimensional Transesophageal Echocardiography During Procedures in Fontan Patients.

3D transesophageal echocardiography (3D-TEE) has proven useful and accurate during some operating room (OR), interventional cardiac catheterization (Cath), and electrophysiologic (EP) procedures. The use of 3D-TEE during similar procedures in patients who have undergone Fontan surgery and its additional value have not been previously reported. To determine if live 3D-TEE during procedures post Fontan has added value, 3D-TEEs in 58 post-Fontan patients over a 5-year study period were reviewed. Additional information provided by 3D-TEE (over 2D-TEE) was classified into the following: A: new information which changed/refined the plan and 0: no new important information. Pre- and post-bypass OR 3D-TEEs were counted as one study. A total of 67 3D-TEEs (41 Cath, 13 OR, and 13 EP procedures) were performed. Median age was 14 years (6-39 years). Median weight was 47 kg (21-109 kg). In Cath procedures, only 2/41 (5%) were graded A (R to L atrial level shunt [Fontan leak], n = 1; thrombus in pulmonary artery stump, n = 1). In the OR, 6/13 (46%) were graded A (atrioventricular valvuloplasty, n = 1; neo-aortic valvuloplasty, n = 1; relief of systemic and pulmonary venous outflow obstruction, n = 2 and n = 2; respectively). In EP procedures, 4/13 (31%) were graded A (thrombus, n = 3; mapping for lead placement to assist in multisite pacing for dyssynchrony, n = 1). 3D-TEE of Fontan improved visualization and frequently added value in the OR/EP lab and may be helpful in select catheterization cases. Future studies with a larger sample could build on this data to identify when 3D-TEE will be most useful.

Right Ventricular Mechanical Dyssynchrony in Hypoplastic Left Heart Syndrome: Correlation with Systolic Function and QRS Duration.

The single right ventricle (RV) in hypoplastic left heart syndrome (HLHS) often develops systolic dysfunction with time and this affects prognosis. Mechanical dyssynchrony has been reported in HLHS but has not consistently correlated with systolic function or electrical dyssynchrony. The aims of this study were to assess the relationship between RV mechanical dyssynchrony, RV systolic function, and QRS duration on surface electrocardiography. We hypothesized that surface QRS duration would not be an adequate indicator of mechanical dyssynchrony compared with dyssynchrony parameters. Retrospective analysis of echocardiograms of patients with HLHS divided into preserved vs reduced RV function. We measured two RV function parameters: (1) fractional area change (FAC) and (2) global longitudinal strain (RVGLS). We measured two dyssynchrony parameters: (1) the standard deviation of the time to peak strain for 9 segments (tPS-9) and (2) time difference between the earliest and latest time to peak strain (RV dyssynchrony index or RVDI) both corrected for R-R interval. We also measured the QRS duration from surface EKG. Mechanical dyssynchrony parameters were compared to both RV systolic function and to QRS duration. 41 patients with HLHS were identified: 21 had preserved function and 20 had reduced function defined by a FAC < 35%. The reduced function group had a significantly lower mean FAC and RVGLS. RVDI was higher in the dysfunction group and had a modest correlation with FAC (r = 0.48) and RVGLS (r = 0.57). tPS-9 was longer in the dysfunction group and had a modest correlation with FAC (r = 0.45) and RVGLS (r = 0.57). QRS duration was longer in the dysfunction group and had a modest correlation with FAC (r = 0.56) and RVGLS (r = 0.56). The weakest correlations were between QRS duration and tPS-9 (r = 0.32) and QRS duration and RVDI (r = 0.10). RV dysfunction measured by FAC was associated with mechanical dyssynchrony measured by increased RVDI and tPS-9. QRS duration was longer in the group with dysfunction but did not correlate with directly measured mechanical dyssynchrony. This may have potential implications for cardiac resynchronization therapy in univentricular patients as assessed by mechanical dyssynchrony parameters rather than QRS duration alone.

Saline Contrast Transesophageal Echocardiography in Fontan Patients: Assessment of the Presence, Type, and Size of Right to Left Shunts.

Right to left (R-L) shunts resulting in cyanosis or systemic embolization occur after the Fontan procedure. The primary modality of diagnosing these is angiography. Successful delineation of these shunts in Fontan patients using selective saline contrast transesophageal echocardiography (SCTEE) may allow for reduced radiation and contrast exposure. We hypothesized that SCTEE could accurately determine the presence, type, and semiquantitative shunt size of R-L shunts in Fontan patients. SCTEE was performed in Fontan patients undergoing angiography for clinical indications. Injections were performed in six sites: mid-Fontan, right and left pulmonary arteries, superior and inferior vena cavae, and innominate vein. R-L shunt size was subjectively graded as 0 = absent, 1 = small, and 2 = medium or large based on echo contrast density in the left atrium. SCTEE was compared to angiography. 33 patients with Fontan were studied with median age 15 years, median weight 50.1 kg, and median O2 saturation of 90% in the R-L shunt group and 95% in the no R-L shunt group. R-L shunt types included intracardiac shunts (ICS), veno-venous collaterals (VVCs), arteriovenous malformations (AVMs), and their combinations. SCTEE versus angiography results were the same for the presence, type, and size of R-L shunts in 79% (26/33). SCTEE identified shunts in 88% (29/33). Angiography identified shunts in 85% (28/33). Neither method missed any medium or large R-L shunts. SCTEE and angiography had similar accuracy. SCTEE accurately detected the presence, type, and size of R-L shunts in most Fontan patients in this study. This can be used to guide targeted angiography, reducing radiation exposure and contrast load.

Semi-automated speckle-tracking for quantitative right ventricular assessment in children and adolescents.

BACKGROUND: Assessment of right ventricular size and function is an important part of the clinical cardiac evaluation; however, these quantitative measures are challenging by echocardiography. Automated software could be useful in place of manual measurements and qualitative assessment. This study evaluates a semi-automated software by comparing automated to manual measures in normal children. METHODS: Neonates to adolescents with normal echocardiograms were prospectively enrolled. Measurements were performed using manual techniques and semi-automated software (EchoInsight®, Epsilon Imaging, Ann Arbor, Michigan, United States of America). Right ventricular measurements included end-diastolic and end-systolic area, fractional area change, chamber dimensions, and tricuspid annular plane systolic excursion. Agreement between manual and semi-automated measures was compared. RESULTS: Echocardiograms for 233 patients were included in the analysis. Intra- and inter-observer reliabilities for semi-automated measures were good with intraclass correlation coefficients all over 0.9 and 0.85, respectively. There was very strong correlation between manual and semi-automated methods for areas and dimensions (r = 0.93-0.99) and low bias (1.4-10.8%). For functional measures, tricuspid annular plane systolic excursion measures correlated well (r = 0.84), but fractional area change did not (r = 0.50). Both demonstrated significant bias (33.5-43.0%). The semi-automated method consistently underestimated fractional area change with a mean of 26.6% versus a manual mean of 36.1%. CONCLUSIONS: The semi-automated software is capable of generating quantitative right ventricular measures in children with good reliability. The software demonstrates very good correlation and low bias when compared to manual methods for right ventricular areas and dimensions. There is a significant difference between manual and semi-automated techniques for the functional measures.

Right Ventricular Systolic Function Parameters in Hypoplastic Left Heart Syndrome.

Assessment of the systolic function of the right ventricle (RV) in patients with hypoplastic left heart syndrome (HLHS) is important. The asymmetric shape and heavy trabeculations make accurate assessment of RV systolic function challenging. Novel measures of RV function could be helpful in distinguishing reduced versus preserved function in HLHS and may also be worse in HLHS with preserved function compared to normal controls. These novel methods offer promise, but research and clinical applicability is hindered as no cut-off values for normal function have been established. We performed a retrospective comparison of functional assessments from echocardiograms of HLHS patients with preserved and reduced RV function along with a control group of normal patients. Measures of function included fractional area change (FAC), tissue motion annular displacement of the tricuspid (TMAD-TV) and pulmonary valves (TMAD-PV), myocardial performance index (MPI), tricuspid tissue Doppler S' velocity, and RV global longitudinal strain (RVGLS). Comparisons were made between three groups: normal patients, HLHS with preserved function, and HLHS with reduced function defined as FAC < 35%. FAC was chosen as the reference as it is a historical standard. 41 HLHS patients were studied. Of these patients, 20 had HLHS with reduced function, and 21 had preserved function. They were compared with 27 age-matched, normal, controls. Comparison between HLHS and normal controls: in HLHS with preserved RV systolic function, compared to normal controls, tissue Doppler S', MPI, and TMAD-TV were all abnormal (all p < 0.05). RVGLS was not statistically different (20.5 ± 3.6% for normal vs. 17.9 ± 2.6% for HLHS with preserved function). TMAD-PV was similar between groups (16.1 ± 4.6% vs. 16.7 ± 5.1%). All measures were significantly worse (all p < 0.05) in the HLHS with reduced function group compared to normal controls. Comparison between HLHS preserved vs reduced function: in HLHS with reduced function defined by FAC < 35%, all measures were significantly worse compared to HLHS with preserved function (all p < 0.05). The cut-off values that correspond to a FAC of > 35% were 14.5% for TMAD-TV and 16% for RVGLS. All measures except RVGLS and TMAD-PV estimated worse function than controls even for HLHS with preserved function. Each of the functional measures was able to identify preserved vs reduced function in HLHS with FAC as the reference standard. Cut-off values between preserved and reduced function in HLHS were estimated for TMAD-TV and RVGLS based on a relatively small cohort. These cut-off values will aid in the research design of future studies.

Right Ventricular Longitudinal Shortening Before and After Stage I Surgical Palliation Correlates with Outcomes.

Quantification of right ventricular function is difficult, but important, in patients with single ventricles. Tissue motion annular displacement (TMAD) is an echocardiographic tool that measures displacement of the tricuspid valve relative to the apex. We evaluated TMAD, lateral annular displacement (LAD), and fractional area change (FAC) for correlation with outcomes. We measured TMAD, LAD, FAC, and other variables that may affect prognosis in patients with single right ventricle physiology pre- and post-Stage I palliation and correlated them with outcomes up to the Glenn procedure. Intra- and inter-observer variability for TMAD measurements were 2.7% (1.2-3.5%) and 6.1% (3.3-8.1%), respectively. Sixty-six subjects met the inclusion criteria. Pre-Stage I TMAD was 13.7% (SD 3.9%). TMAD had a linear relationship with FAC (r2 = 0.76). There was a correlation between TMAD and hospital stay (p = 0.044) and ECMO/arrest (p = 0.024). LAD correlated with ECMO/arrest (p = 0.045) and mortality/transplant (p = 0.049). FAC correlated with in-hospital mortality (p = 0.028). Post-Stage I TMAD was 11.8% (SD 3.7%). TMAD, LAD, and FAC all correlated with in-hospital mortality and mortality/transplant. In multivariate models, TMAD was independently predictive of weight for age Z score pre-Glenn. TMAD, FAC, and LAD correlate with clinically significant outcomes after the first-stage palliation. TMAD correlated with more outcomes than FAC and was the only measure that was independently predictive of any outcome. TMAD is a reproducible measure of RV function in this population. TMAD has prognostic value before and after first-stage palliation and may outperform more traditional measures.

Three-dimensional transesophageal echocardiography of atrial septal defect device closure.

Most secundum atrial septal defects (ASD) are amenable to device closure. Three- dimensional transesophageal echocardiography (3DTEE) can be used to obtain an en face view of the ASD and important surrounding structures which provides for analysis of the type, size, shape, orientation, number and position of orifices, ASD rims and important surrounding structures in a single live 3D echo view. Also, 3DTEE is ideal for monitoring the position and configuration of devices and delivery hardware using live real -time imaging techniques. In this chapter we will describe and illustrate the methods to obtain and optimize 3DTEE en face views of the ASD during device closure using 3D zoom, live 3D and 3D full volume plus iCrop modalities. The respective 3D TEE modalities, imaging protocols, advantages and limitations will be discussed. Because it is useful, accurate and fairly simple to use, we have adopted 3D TEE for routine clinical use during ASD device closure.

Transesophageal echocardiography of intracardiac thrombus in congenital heart disease and atrial flutter: the importance of thorough examination of the Fontan.

Transesophageal echocardiography (TEE) is used in atrial flutter or fibrillation (AFF) before electric cardioversion to detect intracardiac thrombi. Previous studies have described the use of TEE to diagnose intracardiac thrombi in the left atrium and left atrial appendage, which has an incidence of 8 % among patients without congenital heart disease (CHD). In their practice the authors have noted a significant incidence of intracardiac thrombi in other structures of patients with CHD and AFF. This study aimed to determine the incidence and location of intracardiac thrombi using TEE in patients with CHD requiring electric cardioversion of AFF and to compare the use of TEE and transthoracic echo (TTE) to detect intracardiac thrombus in this population. A retrospective chart review of TEE and TTE findings for all patients with CHD who had electric cardioversion of AFF at our institution from 2005 to 2013 was conducted. The diagnosis, presence, and location of intracardiac thrombus were determined. The TEE and TTE results were compared. The study identified 27 patients with CHD who met the study entry criteria at our institution between 2005 and 2013. Seven of these patients had a single ventricle with Fontan palliation. All the patients presented with AFF and had TEE before electric cardioversion. No patients were excluded from the study. The patients ranged in age from 2 to 72 years (median, 21 years) and weighed 17-100 kg (median, 65 kg). The duration of AFF before TEE and attempted cardioversion ranged from 1 day to 3 weeks (median, 3.5 days). Intracardiac thrombus was present in 18 % (5/27) of the patients and in 57 % (4/7) of the Fontan patients with AFF. No embolic events were reported acutely or during a 6-month follow-up period. Among patients with CHD who present with AFF, a particularly high incidence of intracardiac thrombi is present in the Fontan patients that may be difficult to detect by TTE. Thorough TEE examination of the Fontan and related structures is indicated before electric cardioversion of AFF. The incidence of intracardiac thrombus in CHD patients is more than double that reported in non-CHD patients.

Materials Characterization of Stereolithography 3D Printed Polymer to Develop a Self-Driven Microfluidic Device for Bioanalytical Applications.

Stereolithography (SLA) 3D printing is a rapid prototyping technique and reproducible manufacturing platform, which makes it a useful tool to develop advanced microfluidic devices for bioanalytical applications. However, limited information exists regarding the physical, chemical, and biological properties of the photocured polymers printed with SLA. This study demonstrates the characterization of a commercially available SLA 3D printed polymer to evaluate the potential presence of any time-dependent changes in material properties that may affect its ability to produce functional, capillary-action microfluidic devices. The printed polymer was analyzed with Fourier transform infrared-attenuated total reflectance, contact angle measurements, tensile test, impact test, scanning electron microscopy, and fluid flow analysis. Polymer biocompatibility was assessed with propidium iodide flow cytometry and an MTT assay for cell viability. The material characterization and biocompatibility results were then implemented to design and fabricate a self-driven capillary action microfluidic device for future use as a bioanalytical assay. This study demonstrates temporally stable mechanical properties and biocompatibility of the SLA polymer. However, surface characterization through contact angle measurements shows the polymer's wettability changes over time which indicates there is a limited postprinting period when the polymer can be used for capillary-based fluid flow. Overall, this study demonstrates the feasibility of implementing SLA as a high-throughput manufacturing method for capillary action microfluidic devices.

Development of a Resilience Parameter for 3D-Printable Shape Memory Polymer Blends.

The goal of this paper was to establish a metric, which we refer to as the resilience parameter, to evaluate the ability of a material to retain tensile strength after damage recovery for shape memory polymer (SMP) systems. In this work, three SMP blends created for the additive manufacturing process of fused filament fabrication (FFF) were characterized. The three polymer systems examined in this study were 50/50 by weight binary blends of the following constituents: (1) polylactic acid (PLA) and maleated styrene-ethylene-butylene-styrene (SEBS-g-MA); (2) acrylonitrile butadiene styrene (ABS) and SEBS-g-MA); and (3) PLA and thermoplastic polyurethane (TPU). The blends were melt compounded and specimens were fabricated by way of FFF and injection molding (IM). The effect of shape memory recovery from varying amounts of initial tensile deformation on the mechanical properties of each blend, in both additively manufactured and injection molded forms, was characterized in terms of the change in tensile strength vs. the amount of deformation the specimens recovered from. The findings of this research indicated a sensitivity to manufacturing method for the PLA/TPU blend, which showed an increase in strength with increasing deformation recovery for the injection molded samples, which indicates this blend had excellent resilience. The ABS/SEBS blend showed no change in strength with the amount of deformation recovery, indicating that this blend had good resilience. The PLA/SEBS showed a decrease in strength with an increasing amount of initial deformation, indicating that this blend had poor resilience. The premise behind the development of this parameter is to promote and aid the notion that increased use of shape memory and self-healing polymers could be a strategy for mitigating plastic waste in the environment.

Development and Characterization of Furfuryl-Gelatin Electrospun Scaffolds for Cardiac Tissue Engineering.

In this study, three types of electrospun scaffolds, including furfuryl-gelatin (f-gelatin) alone, f-gelatin with polycaprolactone (PCL) in a 1:1 ratio, and coaxial scaffolds with PCL (core) and f-gelatin (sheath), were developed for tissue engineering applications. Scaffolds were developed through single nozzle electrospinning and coaxial electrospinning, respectively, to serve as scaffolds for cardiac tissue engineering. Uniform fibrous structures were revealed in the scaffolds with significantly varying average fiber diameters of 760 ± 80 nm (f-gelatin), 420 ± 110 nm [f-gelatin and PCL (1:1)], and 810 ± 60 nm (coaxial f-gelatin > PCL) via scanning electron microscopy. The distinction between the core and the sheath of the fibers of the coaxial f-gelatin > PCL electrospun fibrous scaffolds was revealed by transmission electron microscopy. Thermal analysis and Fourier transformed infrared (FTIR) spectroscopy revealed no interactions between the polymers in the blended electrospun scaffolds. The varied blending methods led to significant differences in the elastic moduli of the electrospun scaffolds with the coaxial f-gelatin > PCL revealing the highest elastic modulus of all scaffolds (164 ± 3.85 kPa). All scaffolds exhibited excellent biocompatibility by supporting the adhesion and proliferation of human AC16 cardiomyocytes cells. The biocompatibility of the coaxial f-gelatin > PCL scaffolds with superior elastic modulus was assessed further through adhesion and functionality of human-induced pluripotent stem cell (hiPSC)-derived cardiomyocytes, thereby demonstrating the potential of the coaxially spun scaffolds as an ideal platform for developing cardiac tissue-on-a-chip models. Our results demonstrate a facile approach to produce visible light cross-linkable, hybrid, biodegradable nanofibrous scaffold biomaterials, which can serve as platforms for cardiac tissue engineered models.

Hypoplastic left heart syndrome and aortic atresia-mitral stenosis variant: role of myocardial protection strategy and impact of ventriculo-coronary connections after stage I palliation.

Aortic atresia-mitral stenosis (AA-MS) has been implicated as a determinant of outcome after Stage-1 palliation (S1P) in hypoplastic left heart syndrome (HLHS).Studies evaluating the association of AA-MS with ventriculo-coronary connections (VCC) and mortality report conflicting results. The significance of VCC, myocardial protection, and shunt strategy after S1P has yet to be determined. Between January 2005 and July 2009, 100 neonates with HLHS underwent S1P. Mitral and aortic valves and presence of VCC were assessed. Antegrade continuous cold blood cardioplegia was administered throughout the vast extent of the neo-aortic reconstruction. A right ventricle-to-pulmonary shunt was used for an ascending aortic diameter of 0.6 mm/kg or less. Survival analysis was performed to determine predictors and assess impact of AA-MS and VCC on hospital and interstage mortality. Twenty-seven (of 100) patients had AA-MS. The mean age and weight at S1P were 6.5 ± 2.8 days and 3.09 ± 0.47 kg, respectively. VCC were found in 56% of AA-MS. Twenty-two had Norwood-Sano, 3 had classic Norwood, and 2 had hybrid S1P. VCC were associated with AA-MS, endocardial fibroelastosis, and ascending aortic size <2 mm (P < 0.05) but not higher mortality (P = ns). Operative and interstage survival for AA-MS after S1P was 85.2 and 71%, respectively (not statistically different compared to all other subtypes; P = ns). Actuarial survival after S1P at 1, 3, 6, 12, and 36 months was 92.9 ± 4.9, 78.6 ± 7.8, 75 ± 8.2, 71.3 ± 8.3, and 71.3 ± 8.3%, respectively. Intact atrial septum and post-S1P renal dysfunction (P < 0.05) were independent predictors of hospital and interstage mortality. In patients with HLHS, AA-MS carries no survival disadvantage after S1P during the hospital and interstage period regardless of VCC. Intact atrial septum and post-S1P renal dysfunction predict early and interstage mortality. Myocardial protection and shunt strategy might influence the outcome in this HLHS variant.

Design of Shape Memory Thermoplastic Material Systems for FDM-Type Additive Manufacturing.

The work presented here describes a paradigm for the design of materials for additive manufacturing platforms based on taking advantage of unique physical properties imparted upon the material by the fabrication process. We sought to further investigate past work with binary shape memory polymer blends, which indicated that phase texturization caused by the fused filament fabrication (FFF) process enhanced shape memory properties. In this work, two multi-constituent shape memory polymer systems were developed where the miscibility parameter was the guide in material selection. A comparison with injection molded specimens was also carried out to further investigate the ability of the FFF process to enable enhanced shape memory characteristics as compared to other manufacturing methods. It was found that blend combinations with more closely matching miscibility parameters were more apt at yielding reliable shape memory polymer systems. However, when miscibility parameters differed, a pathway towards the creation of shape memory polymer systems capable of maintaining more than one temporary shape at a time was potentially realized. Additional aspects related to impact modifying of rigid thermoplastics as well as thermomechanical processing on induced crystallinity are also explored. Overall, this work serves as another example in the advancement of additive manufacturing via materials development.

Ventriculocoronary artery connections with the hypoplastic left heart: a 4-year prospective study: incidence, echocardiographic and clinical features.

Ventriculocoronary connections (VCCs), also called sinusoids, occur with hypoplastic left heart (HLH). Previous reports are limited to case reports, pathologic series, and surgical series with limited detail, which may underestimate the incidence and overestimate the severity of VCCs in HLH. A study was conducted to determine the incidence VCCs in HLH, their effect on survival, and their echocardiographic and clinical features. The echocardiograms and medical records of 100 consecutive neonatal HLH cases were analyzed. All had an aortic and a mitral valve diameter and a left ventricular (LV) volume less than Z-3. For palliation, Norwood, Sano, or hybrid procedures were used, and if the patient was alive, subsequent bidirectional Glenn and extracardiac Fontan procedures were applied. Cases were classified as manifesting mitral and aortic atresia (MAAA), mitral and aortic stenosis (MSAS), or mitral stenosis and aortic atresia (MSAA). All other diagnoses or any case with additional cardiac anomalies were excluded from the study. Overall, VCCs were found in 15% of the cases. They occurred in 56% of the MSAA subtype cases and were not statistically associated with a high mortality rate. However, in one case, large and multiple VCCs definitely caused or contributed to early death. All VCCs had a transmyocardial course, a turbulent color-Doppler flow, and a dominant usually retrograde systolic coronary artery flow pattern. The VCCs were associated (p < 0.05) with MSAA, endocardial fibroelastosis, and ascending aortic size less than 2 mm. As shown by the findings, 15% of the HLH patients had MSAA with VCCs. Unless the VCCs were large or extensive, they did not contribute to mortality. Detailed echocardiographic analysis of VCCs in HLH was feasible. Recent reports emphasize more severe cases.

Tissue Motion Annular Displacement Predicts Mortality/Transplant After the Bidirectional Glenn.

BACKGROUND: Quantifying right ventricular function in patients with a systemic right ventricle (RV) is difficult but important for prognosis. Tissue motion annular displacement tracks displacement of the tricuspid annulus toward the apex. We evaluated this measure alongside fractional area change (FAC) on patients with single, RV prior to the bidirectional Glenn procedure. We tested both measures for correlation with outcomes. METHODS: Retrospective measurement of tissue motion annular displacement and FAC was performed on echocardiographic clips obtained prior to the bidirectional Glenn. A chart review included postoperative outcomes and midterm mortality/transplant. Bivariate correlations and Cox proportional hazards models were used for analyses. RESULTS: Fifty-one patients with dominant RV underwent the bidirectional Glenn procedure and all had image quality that allowed analysis. The age ranged from 3 to 11 months (median 4 months). Neither tissue motion annular displacement nor FAC correlated with short-term postoperative outcomes. Tissue motion annular displacement was independently predictive of mortality/transplant ( P = .03) in the Cox hazard model. The mean for survivors was 12.4% and for nonsurvivors/transplants was 10.0%. Tissue motion annular displacement intra-observer variability was 2.8% (1.2%-3.5%). Interobserver mean variability was 6.1% (3.3%-8.1%). Fractional area change was not predictive of mortality/transplant. CONCLUSION: Tissue motion annular displacement is an independent predictor of midterm mortality/transplant after the bidirectional Glenn procedure in patients with single, RV, in this study. It may outperform FAC in this regard and has good reproducibility. Tissue motion annular displacement may be a useful measure in identifying high-risk children in this population.

Three-dimensional analysis of regional right ventricular shape and function in repaired tetralogy of Fallot using cardiovascular magnetic resonance.

BACKGROUND: Patients with surgically repaired tetralogy of Fallot (rTOF) often have residual pulmonic valve regurgitation, leading to abnormal remodeling and dysfunction of the right ventricle often requiring pulmonic valve replacement. We tested the hypothesis that 3D analysis of right ventricular (RV) shape and function may reveal differences in regional adaptive remodeling that occurs in patients with rTOF, depending on whether a transannular patch (TAP) was utilized. METHODS: Forty patients with rTOF who underwent cardiac magnetic resonance imaging (1.5 T), including 20 with and 20 without TAP, and 10 normal controls were studied. Images were analyzed to measure RV endocardial curvature and global and regional volume and function. RESULTS: RV ejection fraction (EF) was 42 ±â€¯11% in TAP and 38 ±â€¯9% in no-TAP (p = 0.19), both lower than 54 ±â€¯3% in controls (p < 0.01). Left ventricular (LV) EF was 54 ±â€¯9% in TAP, 54 ±â€¯8% in no-TAP (p = 0.87) and 61 ±â€¯16% in controls (both p < 0.01). Indexed LV end-diastolic volumes were higher in no-TAP than in TAP subgroup (p = 0.02). With TAP, mid RV septum showed lower curvature during diastole (less convex), than the mid and apical free walls and free wall adjacent to the RV outflow tract (RVOT; more convex). There were no differences in curvature during systole between rTOF subgroups but mid and RVOT free walls showed higher curvature versus controls. CONCLUSIONS: This is the first study to comprehensively describe the influence of TAP on changes in regional RV shape in patients with rTOF. Understanding these differences may help guide therapeutic options for residual pulmonary valve regurgitation in rTOF patients.

Three-Dimensional Echocardiographic En Face Views of Ventricular Septal Defects: Feasibility, Accuracy, Imaging Protocols and Reference Image Collection.

BACKGROUND: Ventricular septal defect (VSD) is the most common congenital cardiac anomaly. Accurate assessment is critical for planning treatment. Recent advances in three-dimensional (3D) echocardiography have improved image quality and ease of use. METHODS: The feasibility and accuracy of three specific 3D echocardiographic protocols to demonstrate en face views of VSDs were analyzed in a retrospective review of 100 consecutive patients. Sixty-four patients underwent transthoracic echocardiography and 36 transesophageal echocardiography. Types of VSDs included 34 muscular, 32 perimembranous, 18 malaligned, 11 inlet, four outlet, and one acquired. Ages ranged from 1 day to 77 years, and body weights from 3 to 92 kg. Three-dimensional echocardiographic full-volume mode with standard XYZ and adjustable plane cropping, 3D full-volume mode with iCrop, and narrow-sector live 3D protocols were compared for feasibility and accuracy to obtain a diagnostic-quality en face view of a VSD. RESULTS: The success rate for obtaining a high-quality en face image for the three protocols was 100% for full-volume mode with iCrop, 97% for full-volume standard mode, and 94% for narrow-sector live 3D mode. The ability of both full-volume mode with iCrop and full-volume standard mode to demonstrate a VSD was slightly better than that of narrow-sector live 3D mode (P < .001 for both vs narrow-sector live 3D mode). In all patients, the type, size, and location of the VSD were demonstrated accurately by two or more of the protocols. CONCLUSIONS: Three-dimensional echocardiography of VSDs is feasible and accurate in most patients using defined protocols. The protocols are described and illustrated in detail, and a reference 3D image collection is presented.

Intermediate results of the anatomic repair for congenitally corrected transposition.

BACKGROUND: Anatomic repair of congenitally corrected transposition of the great arteries has several advantages over the traditional approach but lacks long-term evaluation. METHODS: The data on 12 patients who had the procedure between January 1989 and June 2000 were retrospectively reviewed. Associated lesions included ventricular septal defect in 12 patients, pulmonary stenosis in 10 patients, and moderate to severe tricuspid valve regurgitation in 4 patients. Mean age at operation was 9+/-3.6 months. All patients had venous switch Mustard procedure. Tunneling of the morphologic left ventricle through the ventricular septal defect to the aorta with insertion of right ventricular to pulmonary artery conduit was performed in 10 patients, and arterial switch operation in 2. Concomitant tricuspid valvuloplasty was done in 2 patients and ventricular septal defect enlargement in 1. RESULTS: There was one hospital death (9%) in the patient who needed ventricular septal defect enlargement. Complications included atrioventricular block requiring pacemaker insertion in 1 patient (9%) and superior vena caval obstruction in 1 patient (9%). Follow-up is available on all patients 0.5 to 10 years (mean, 7.6+/-3.1 years). All patients are asymptomatic. Exercise test results on the three oldest patients were normal. Bradytachyarrhythmias developed in 4 patients (36%). Right ventricular to pulmonary artery conduit replacement was needed in 5 patients 2.2 to 7.1 years (mean 5.2+/-3.6 years) postoperatively. Mild to moderate tricuspid valve regurgitation persisted in 2 patients. Systemic left ventricular fractional shortening was 36% to 47% (mean, 39%+/-4.6%), and ejection fraction was 49% to 70% (mean, 60.8%+/-7.9%). CONCLUSIONS: The double switch operation can be performed safely with minimal intermediate and long-term complications.

Significance of low peak Doppler velocity in the proximal sano conduit in hypoplastic left heart syndrome.

BACKGROUND: The Sano modification of the Norwood operation is a well-established first step palliation for hypoplastic left heart syndrome (HLHS). Theoretically, the first point of resistance to pulmonary flow should be in the proximal Sano, generating high Doppler flow velocity. Paradoxically, however, some patients have low gradients in the proximal Sano conduit. The objective of this study was to determine the hemodynamic and anatomic significance of low proximal Sano Doppler flow velocity and its clinical implications. METHODS: Doppler-derived peak gradients in the proximal Sano conduits were measured in HLHS patients after Norwood-Sano surgery over a 4-year period and confirmed by cardiac catheterization within 2 to 4 weeks. Clinical outcomes of patients with proximal Sano gradients of 30 mm Hg or less (group 1) were compared with patients whose gradient was greater than 30 mm Hg (group 2). RESULTS: Of the 53 patients, 21 (40%) belonged to group 1. Patients in group 1 had smaller ostial right and left pulmonary artery (PA) diameter (3.2 ± 1.2 mm versus 4.5 ± 1.8 mm, p = 0.03; and 3.4 ± 1.2 mm versus 5.6 ± 2.1 mm, p = 0.01) when compared with patients in group 2. Patients (7 of 10) who needed either balloon angioplasty of a distal Sano or proximal branch PA were from group 1 (p = 0.01). Patients in group 1 had higher rates of unintended PA interventions (33% versus 9%) and complications (48% versus 16%) compared with group 2. CONCLUSIONS: Low peak Doppler flow velocity in the proximal Sano correlates with the presence of either distal Sano stenosis or proximal branch PA stenosis. These patients require close follow-up in the interstage period and may need earlier intervention.