Right Ventricular Outflow Tract Diameter Research Articles

Right Ventricular Outflow Tract Diameter Change with Exercise: a Prospective Exercise Echocardiography and Invasive CPET study

Abstract While cardiac output reserve with exercise predicts outcomes in cardiac and pulmonary vascular disease, precise quantification of exercise cardiac output requires invasive cardiopulmonary testing (iCPET). To improve the accuracy of cardiac output reserve estimation with transthoracic echocardiography (TTE), this prospective study aims to define changes in right ventricular outflow tract diameter (RVOTd) with exercise and its relationship with invasively measured hemodynamics. 20 subjects underwent simultaneous TTE and iCPET, with data collected at rest, leg-raise, 25W, 50W (n = 16), 75W (n = 14), 100W (n = 6). This was followed by a second exercise study with real-time RV pressure-volume loops at similar stages (except leg-raise). The overall cohort included heart failure with preserved ejection fraction (n = 12), pulmonary arterial hypertension (n = 5), and non-cardiac dyspnea (n = 3).RVOTd was reverse engineered from the TTE-derived RVOT velocity time integral (VTI) and iCPET-derived stroke volume, using the formula: Fick stroke volume = RVOT VTI x RVOT area (wherein RVOT area = π x [RVOTd/2]2). RVOTd increased by nearly 3-4% at every 25W increment. Using linear regression models, where each subject is treated as a categorical variable and adjusting for subject intercept, RVOTd was correlated with hemodynamic variables (cardiac output, heart rate, pulmonary artery and RV pressures). Of all the predictor hemodynamic variables, cardiac output had the highest r2 model fit (adjusted r2 = 0.68), with a unit increase in cardiac output associated with a 0.0678 increase in RVOTd (p < 0.001). Our findings indicate that RVOTd increases by 3-4% with every 25W increment, predominantly correlated with cardiac output augmentation. These results can improve the accuracy of cardiac output reserve estimation by adjusting for RVOTd with graded exercise during noninvasive CPET and echocardiogram. However, future studies are needed to define these relationships for left ventricular outflow tract diameter.

Abstract 14195: Right Ventricular Outflow Tract Diameter Increase With the Low-Moderate Workload: A Prospective Simultaneous Exercise Echocardiography and Invasive Cardiopulmonary Exercise Testing Study

Background: While cardiac output at rest can be estimated non-invasively with echocardiogram, change in left ventricular or right ventricular outflow tract diameter (RVOTd) with exercise makes the cardiac output estimation inaccurate. Hypothesis: RVOTd increases with exercise proportionally with an incremental workload and is determined by stroke volume augmentation. Aims: 1. Define a workload-based change in RVOTd in subjects undergoing invasive cardiopulmonary exercise test (iCPET). 2. Correlate RVOTd at exercise stages with iCPET metrics. Methods: 20 subjects undergoing simultaneous echocardiogram and iCPET were enrolled in a prospective study. Exercise datapoints were acquired at 25 W (n=20), 50W (n=16), 75W (n=14), 100W (n=6). Three hemodynamic groups included: HFpEF (n=12), PAH (n=5), controls (n=3). Utilizing iCPET-based direct Fick cardiac output and stroke volume, RVOTd was reverse engineered with RVOT velocity time integral, per ASE guidelines. Pearson correlation was used to assess correlation of RVOTd with hemodynamic metrics. p<0.05* Results: In overall cohort, age was 64±12 years, BMI 31.2±4.9 Kg/m 2 , female 60%, peak VO 2 13.7±5.7 mL/Kg.min -1 and V E /VCO 2 37±8. Increase in RVOTd with exercise is represented in the Figure. In comparison to rest, RVOTd increased significantly even at low-25W (+4.1±13.6%*) and moderate-50W (+7.6±17.2%*) workloads. Overall, RVOTd increased by 4-5% every 25W. At high workload (100W), the diameter increased by 24% (n=6). There were no differences in RVOT diameter between subgroups. RVOTd at four exercise stages (25W, 50W, 75W, 100W) correlated significantly with stroke volume index (r=0.68*, 0.80*, 0.23, 0.64) and cardiac output (r=0.50*, 0.80*, 0.08, 0.68), but non-significantly with heart rate (r=-0.15, 0.19, -0.10, 0.68). Conclusion: RVOTd increases by 4-5% every 25W on an incremental workload protocol. This behavior is predominantly associated with an increase in stroke volume index with exercise.

Protocol for rheumatoid arthritis complicated with cardiovascular damage treated with Guanxining tablet with a randomized controlled trial

BackgroundCardiovascular disease (CVD) is the main cause of death in patients with rheumatoid arthritis (RA). Apart from traditional cardiovascular risk factors, immune dysfunction and chronic inflammation of RA are also risk factors for complex cardiovascular damage. Although methotrexate (MTX) is beneficial to CVD in RA patients by inhibiting inflammation, its adverse effects limit its clinical application. Therefore, it is essential to seek safer and more effective drugs. ObjectiveWe aimed to assess the efficacy of Guanxining Tablet (GXNT) for rheumatoid arthritis complicated with cardiovascular damage. MethodsWe will conduct a prospective single-center randomized trial. We will randomly divide 56 eligible patients into two groups. The treatment group will take GXNT and MTX treatment, and the control group will receive MTX and the placebo. The primary outcome measure will be aortic distensibility (AD). Secondary outcome measures will be Cardiac function which will contain right ventricular outflow tract diameter (RVOTD), aortic diameter (AOD), left atrium diameter (LAD), right ventricular end diastolic diameter (RVDD), left ventricular end diastolic diameter (LVDD), ejection fraction (EF%), fractional shortening (FS%), stroke volume (SV). Adverse events will be closely monitored during the entire trial period. DiscussionThis trial is intended to determine whether the addition of GXNT will improve the prognosis of patients with rheumatoid arthritis and cardiovascular damage without severe adverse reactions. Completing this clinical trial might provide these patients with a novel and effective drug while avoiding adverse reactions similar to methotrexate. Trial registrationChiCTR2000030247.

The relation of right ventricular outflow tract measurements with in-hospital clinical outcomes after tricuspid valve surgery.

Right ventricular (RV) function is a determining factor for clinical outcomes in patients undergoing tricuspid valve surgery (TVS). Our aim was to investigate the importance of the function of the right ventricular outflow tract (RVOT), which is an important anatomical region of the RV, in patients underwent TVS. 104 patients who underwent TVS were analyzed retrospectively. Patients with previous cardiac surgery, congenital heart disease, or heart failure were excluded. The parasternal short-axis view at the level of the aortic root was used to measure RVOT dimensions and RVOT fractional shortening (RVOT-FS). The effect of RVOT diameter and function on major adverse cardiac events (MACE) after TVS was investigated. In our study, MACE, consisting of pacemaker implantation, acute kidney injury, postoperative atrial fibrillation and mortality, was developed at 44 (42.3%) patients.We compared the predictive performances of RVOT end-systolic (RVOTs) diameter, RVOT end-diastolic (RVOTd) diameter, RVOT-FS and RV diameters in prediction of MACE. The model including the RVOTs had higher AUC, R2 and likelihood ratio X2 values (0.775, 0.287 and 25.0, respectively) than RVOTd (0.770, 0.279 and 24.2, respectively) and RVOT-FS (0.750, 0.215 and 18.1, respectively). RVOT diameters showed better performance in predicting MACE than RV diameters. Moreover, there was statistically significant association between RVOTs, RVOTd and MACE (p value were 0.014 and 0.027, respectively), while no association between RVOT-FS and MACE (p value was 0.177). In summary, we determined that the RVOT diameters are important predictors for the in-hospital clinical outcomes of patients who underwent TVS.

Atrial Septal Defect: Larger Right Ventricular Dimensions and Atrial Volumes as Early as in the First Month After Birth—a Case–Control Study Including 716 Neonates

Atrial septal defect (ASD) is characterized by a left-to-right shunt causing dilatation of the right atrium and right ventricle as well as pulmonary hyperperfusion. The detection of ASDs often occurs late in childhood or adulthood. Little is known about cardiac structure and function in neonates with ASD.We analyzed neonatal echocardiograms from the Copenhagen Baby Heart Study, a multicenter, population-based cohort study of 27,595 neonates. We included 716 neonates with secundum-type ASDs and matched them 1:1 on sex and age at examination with neonates without ASD from the same birth cohort. Neonates with an ASD (median age 11 days, 52% female) had larger right ventricular (RV) dimensions than matched controls (RV longitudinal dimension end-diastole: 27.7 mm vs. 26.7 mm, p < 0.001; RV basal dimension end-diastole: 14.9 mm vs. 13.8 mm, p < 0.001; and RV outflow tract diameter 13.6 mm vs. 12.4 mm, p < 0.001). Atrial volumes were larger in neonates with ASD compared to controls (right atrial end-systolic volume: 2.9 ml vs. 2.1 ml, p < 0.001; and left atrial end-systolic volume 2.0 ml vs. 1.8 ml, p < 0.001). Tricuspid annular plane systolic excursion was larger in neonates with ASD than in controls (10.2 mm vs. 9.6 mm, p < 0.001). Left ventricular dimensions and function did not differ between neonates with ASD and controls. In conclusion, ASDs were associated with altered cardiac dimensions already in the neonatal period, with larger right ventricular dimensions and larger atrial volumes at echocardiography within the first 30 days after birth.ClinicalTrials.gov Identifier: NCT02753348 (April 27, 2016).

Evaluación del tracto de salida del ventrículo derecho mediante resonancia magnética con flujo 4D en pacientes sometidos a recambio valvular pulmonar transcatéter

Introduction and objectivesMagnetic resonance imaging (MRI) including 4D flow is used before percutaneous pulmonary valve implantation (PPVI). As PPVI is limited by the size of the right ventricular outflow tract (RVOT), accurate sizing is needed to plan the intervention. The aim of this study was to compare different MRI modalities and invasive angiogram to balloon sizing of RVOT. MethodsSingle-centre prospective study of patients who underwent PPVI for isolated pulmonary regurgitation assessed by 4D flow MRI, 3D steady-state free precession/gradient echo (3D SSFP/GRE) and contrast magnetic resonance angiogram. Balloon sizing was considered as the reference. ResultsA total of 23 adults were included (mean age, 38.4±12.5 years). Eighteen patients underwent successful primary PPVI. The average of the narrowest RVOT diameter was 25.4±4.3mm by balloon sizing. Compared to balloon sizing, RVOT diameters were better correlated when estimated by systolic 4D flow MRI (r=0.89, P<0.001) than by diastolic 4D flow MRI (r=0.71, P<0.001), 3D contrast magnetic resonance angiography (r=0.73; P<.001) and 3D SSFP/GRE (r=0.50; P=.04) and not significantly correlated when estimated by 2D in diastole and systole. The mean difference between systolic 4D flow MRI and balloon sizing was 0.2mm (95%CI, –3.5 to 3.9 mm), whereas it was wider with other techniques. ConclusionsBeyond the quantification of pulmonary valve regurgitation, 4D flow allows accurate estimation of RVOT diameters, especially in systole, which is fundamental before planning PPVI.

4D flow magnetic resonance imaging to assess right ventricular outflow tract in patients undergoing transcatheter pulmonary valve replacement

Introduction and objectivesMagnetic resonance imaging (MRI) including 4D flow is used before percutaneous pulmonary valve implantation (PPVI). As PPVI is limited by the size of the right ventricular outflow tract (RVOT), accurate sizing is needed to plan the intervention. The aim of this study was to compare different MRI modalities and invasive angiography to balloon sizing of RVOT. MethodsSingle-center prospective study of patients who underwent PPVI for isolated pulmonary regurgitation assessed by 4D flow MRI, 3D steady-state free precession/gradient echo (3D SSFP/GRE) and contrast magnetic resonance angiography. Balloon sizing was considered as the reference. ResultsA total of 23 adults were included (mean age, 38.4±12.5 years). Eighteen patients underwent successful primary PPVI. The average of the narrowest RVOT diameter was 25.4±4.3 mm by balloon sizing. Compared to balloon sizing, RVOT diameters were better correlated when estimated by systolic 4D flow MRI (r=0.89, P<.001) than by diastolic 4D flow MRI (r=0.71, P <.001), 3D contrast magnetic resonance angiography (r=0.73; P <.001) and 3D SSFP/GRE (r=0.50; P=.04) and was not significantly correlated when estimated by 2D in diastole and systole. The mean difference between systolic 4D flow MRI and balloon sizing was 0.2 mm (95%CI, –3.5 to 3.9 mm), whereas it was wider with other techniques. ConclusionsBeyond the quantification of pulmonary valve regurgitation, 4D flow allows accurate estimation of RVOT diameters, especially in systole, which is fundamental before planning PPVI.

Long-Term Electrocardiographic and Echocardiographic Progression of Arrhythmogenic Right Ventricular Cardiomyopathy and Their Correlation With Ventricular Tachyarrhythmias.

Prior studies of structural and electrocardiographic changes in arrhythmogenic right ventricular (RV) cardiomyopathy and their role in predicting ventricular arrhythmias (ventricular tachycardia) have shown conflicting results. We reviewed 405 ECGs, 315 transthoracic echocardiographies, and 441 implantable cardioverter defibrillator interrogations in 64 arrhythmogenic RV cardiomyopathy patients (56% men, mean age [SD], 44.2 [14.6] years) over a mean follow-up of 10 (range, 2.3-19) years. Generalized estimating equations were used to identify the association between ECG abnormalities, clinical variables, and transthoracic echocardiographic measurements (>mild degree of tricuspid regurgitation, RV outflow tract diameter in parasternal long axis and short axis, RV end-diastolic area, fractional area change). There was a 4.65 (95% CI, 0.51%-8.8%) increase in RV end-diastolic area, a 3.75 (95% CI, 1.17%-6.34%) decrease in fractional area change, and 1.9 (95% CI, 1.3-2.8) higher odds (odds ratio) of RV wall motion abnormality with every 5-year increase in age after patients' first transthoracic echocardiography. >Mild tricuspid regurgitation was an independent predictor of RV enlargement and dysfunction (hazard ratio of >10% drop in fractional area change from baseline [95% CI], 3.51 [1.77-6.95] and hazard ratio of >10% increase in RV end-diastolic area from baseline [95% CI], 4.90 [2.52-9.52]). Patients with implantable cardioverter defibrillator were more likely to develop >mild tricuspid regurgitation and larger structural and functional disease progression. More pronounced increase in RV end-diastolic area was translated into higher rates of any ventricular tachycardia. Inferior T-wave inversions and sum of R waves (mm) in V1 to V3 were predictors of RV enlargement and dysfunction with the former also predicting risk of any ventricular tachycardia. Arrhythmogenic RV cardiomyopathy is a progressive disease. Tricuspid regurgitation is an independent predictor of structural disease progression, which may be exacerbated by use of a transvenous implantable cardioverter defibrillator lead.

Echocardiographic Follow-Up of Right Ventricular Function After Tetralogy of Fallot Operation

Aim: Although limited in assessing right ventricular (RV) function, echocardiography is widely used after correction for tetralogy of Fallot (TOF). The change in echocardiographic measurements of RV in asymptomatic patients after TOF repair over a long follow-up time is not explored yet. The variation in simple echocardiographic measurements during follow-up of our TOF patients are presented. The predictive value of those parameters in determining a future pulmonary valve replacement is sought. Method: Asymptomatic patients surviving the first year after correction for simple TOF from February 2007 to December 2019 at Başkent University, Istanbul Hospital are enrolled. Patients are followed annually with echocardiography including: RV area, volume, length, RV outflow tract (RVOT) diameter and gradient, tricuspid annulus diameter, tricuspid lateral annular tissue velocities, tricuspid annular plane systolic excursion, TEI index RV ejection fraction (EF) measurements. The change in the consecutive echocardiographic measurements during follow-up is analysed. Patients are evaluated with a cardiac magnetic resonance (CMR) imaging when deemed necessary and compared with echocardiographic measurements. Results: A total of 66 patients (54.5% males) are operated at age 14.4±9.3 months (78.8% with transannular patch). Twelve patients had pulmonary valve replacement (PVR) operation at an age 10.1±3.1 years. During follow-up of 7.2±4.3 years, tricuspid annulus diameter, RV area, RV inlet length, RV volume, RV volume index significantly increased (p=0.001 for all), whereas RV inlet length index, TEI and TEI z score decreased (p&lt;0.0001 for all). When means are compared, tricuspid annulus (28.8mm vs 25.0mm; p=0.013), RV volume (72.2ml vs 52.2ml; p=0.042), RV inlet length index (77.9mm/m2 vs 60.2mm/m2 ; p=0.013), RVOT diameter (28.7 vs 23.0; p=0.007) are increased. RV EF is decreased (51.3% vs 60.5%; p=0.011) in those requiring PVR. Those with higher RV area index, RV volume index, tricuspid annulus diameter and tricuspid annular z score in their first echocardiography after the TOF repair, are more likely to have a PVR operation later on (p&lt;0.05 for all). RV volume index ≥39ml/m2 predicts a PVR within 7 years with 100% sensitivity and 74% specificity. Tricuspid annular z score less than -0.43 seems to eliminate the possibility of having a PVR within 7 years with a sensitivity of 44% and specificity of 100%. Conclusion: Observing the sequential change in echocardiographic parameters like RV volume index, RV area index, tricuspid annulus z score is reliable in determining right ventricular function and can limit the costly CMR applications. Cut off values of RV volume index &gt;39ml/m2 and tricuspid annulus z score ≥ - 0.43 after the initial TOF repair may determine patients with higher possibility of having early PVR and indicate a closer follow-up.

Alterra Adaptive Prestent and SAPIEN 3 THV for Congenital Pulmonic Valve Dysfunction

The aim of this study was to demonstrate the safety and functionality of the Alterra Adaptive Prestent and SAPIEN 3 transcatheter heart valve (THV) in patients with dysfunctional, dilated right ventricular outflow tract (RVOT) greater or equal to moderate pulmonary regurgitation (PR). Significant variations in the size and morphology of the RVOT affect the placement of transcatheter pulmonary valves. The Alterra Prestent internally reduces and reconfigures the RVOT, providing a stable landing zone for the 29-mm SAPIEN 3 THV. Eligible patients had moderate or greater PR, weighed >20kg, and had RVOT diameter 27 to 38mm and length >35mm. The primary endpoint was device success, a 5-item composite: 1 Alterra Prestent deployed in the desired location, 1 SAPIEN 3 THV implanted in the desired location within the Prestent, right ventricular-to-pulmonary artery peak-to-peak gradient<35mmHg after THV implantation, less than moderate PR at discharge, and no explantation 24h post-implantation. The secondary composite endpoint was freedom from THV dysfunction (RVOT/pulmonary valve (PV) reintervention, greater or equal to moderate total PR, mean RVOT/PV gradient ≥ 35 mm Hg at 30days and 6months. Descriptive statistics are reported. Enrolled patients (N=15) had a median age and weight of 20 years and 61.7kg, respectively; 93.3% were in New York Heart Association functional class I or II. Device success was 100%. No staged procedures were necessary. No THV dysfunction was reported to 6months. No serious safety signals were reported. This early feasibility study demonstrated the safety and functionality of the Alterra Adaptive Prestent in patients with congenital RVOT dysfunction and moderate or greater PR. Durability and long-term outcome data are needed.

Computed tomography guided sizing for transcatheter pulmonary valve replacement

ObjectiveTo evaluate the predictive value of Computed Tomography Angiography (CTA) measurements of the RVOT for transcatheter valve sizing. BackgroundTranscatheter pulmonary valve replacement (TPVR) provides an alternative to surgery in patients with right ventricular outflow tract (RVOT) dysfunction. We studied 18 patients who underwent catheterization for potential TPVR to determine whether CT imaging can be used to accurately predict implant size. MethodsCases were grouped by RVOT characteristics: native or transannular patch (n = 8), conduit (n = 5) or bioprosthetic valve (n = 5). TPVR was undertaken in 14/18 cases, after balloon-sizing was used to confirm suitability and select implant size. Retrospective CT measurements of the RVOT (circumference-derived (Dcirc) and area-derived (Darea) diameters) were obtained at the level of the annulus, bioprosthesis or conduit. Using manufacturer sizing guidance, a valve size was generated and a predicted valve category assigned: (1) <18 mm, (2) 18–20 mm, (3) 22–23 mm, (4) 26–29 mm and (5) >29 mm. Predicted and implanted valves were compared for inter-rater agreement using Cohen’s kappa coefficient. ResultsThe median age of patients was 37 years old (IQR: 30–49); 55% were male. Diagnoses included: Tetralogy of Fallot (12/18), d-Transposition repair (3/18), congenital pulmonary stenosis (2/18) and carcinoid heart disease (1/18). Measurements of Darea (κ = 0.697, p < 0.01) and Dcirc (κ = 0.540, p < 0.01) were good predictors of implanted valve size. When patients with RVOT conduits were excluded, the predictive accuracy improved for Darea (κ = 0.882, p < 0.01) and Dcirc (κ = 0.882, p < 0.01). ConclusionsCT measurement of the RVOT, using Darea or Dcirc, can predict prosthetic valve sizing in TPVR. These measurements are less predictive in patients with conduits, compared to those with a native RVOT or pulmonic bioprosthesis. Condensed abstractWe studied 18 patients who underwent catheterization for TPVR to determine whether CT imaging could be used to accurately predict implant size. Retrospective RVOT measurements were used to generate a predicted valve size, which was compared with implanted valve size for inter-rater agreement. Measurements of Darea (κ = 0.697, p < 0.01) and Dcirc (κ = 0.540, p < 0.01) were good predictors of implanted valve size. When cases with RVOT conduits were excluded, the predictive accuracy improved for Darea (κ = 0.882, p < 0.01) and Dcirc (κ = 0.882, p < 0.01). CT measurement of the RVOT can accurately predict prosthetic valve sizing in TPVR. These measurements are less predictive in patients with conduits.

Different CMR Imaging Modalities for Native and Patch-Repaired Right Ventricular Outflow Tract Sizing: Impact on Percutaneous Pulmonary Valve Replacement Planning.

Percutaneous pulmonary valve replacement (PPVI) in native or patched right ventricular outflow tract (RVOT) has proven to be feasible. The procedure is highly dependent on the size of the RVOT. Several methods exist to evaluate the size of the RVOT by cardiovascular magnetic resonance (CMR). We evaluated different CMR modalities for measuring RVOT diameters. Thirty-one consecutive patients with native or patched RVOT were retrospectively evaluated. CMR was part of follow-up of patients with corrected Tetralogy of Fallot or pulmonary stenosis with significant pulmonary regurgitation (PR). CMR included 3D-SSFP whole-heart in systole, diastole, and contrast-enhanced MR angiography (ceMRA). Diameters of the RVOT were assessed by the three sequences. Additionally, in patients who underwent cardiac catheterization (n = 11) for PPVI, vessel diameters assessed by cine-angiography were compared to CMR. Systolic diameters of RVOT were significantly larger compared to the diameters taken in diastole and ceMRA (median difference 5.0mm and 3.8mm). Diastolic and ceMRA diameters did not differ significantly. CMR diameters taken in systole showed no statistical difference to systolic diameters taken by cine-angiography, while diastolic and ceMRA diameters were significantly smaller. PPVI was feasible to a maximal CMR diameter of 31mm measured by SSFP whole-heart sequence in systole. Absolute diameters of native RVOT differ depending on the CMR sequence and timing of acquisition (systolic vs diastolic gating). Diameters taken during heart catheterization by cine-angiography best correlate to systolic CMR values. Data may help to select RVOTs suitable for PPVI.

P4507Left atrial conduit function modulates functional capacity in heart failure patients acting through the pulsatile component of right ventricular afterload

Abstract Background It has been suggested that left atrial (LA) characteristics modulate the functional capacity in heart failure (HF) patients through the impact that LA cavity exerts on the pulmonary circulation and the pulsatile component of right ventricular (RV) afterload, as represented by pulmonary arterial compliance (PAC). Purpose Thus, we hypothesized that, in a HF patients' population, a larger relative contribution of LA phasic conduit function (PCF) to the left ventricular (LV) stroke volume would be associated with a heavier right ventricular hemodynamic burden and a reduced functional capacity. Methods 60 sinus rhythm HF subjects (42 males, 67±11 years, ejection fraction [EF] 39±11%, range 20% - 62%) underwent 6 minute walking test (6MWT) and routine transthoracic echocardiography, plus real time 3D acquisitions analyzed with a dedicated echo software package. LV ejection fraction (EF) was obtained from 3D echo acquisitions. LV diastolic dysfunction (DD) was assessed according to current guidelines. Computation of PCF was made by simultaneous gathering real time 3D multibeats (6 cycles) LA and LV volumes, using the formula: PCF(time) = [LV(time) − LV minimum] − [LA maximum − LA(time)] as proposed by Bowman &amp; Kovacs (2004), with PCF expressed as % of LV stroke volume. Atrioventricular compliance (Cn) was also assessed, as proposed by Flachskampf et al. (1992): 1270*(mitral valve area/E wave downslope) and expressed in ml/mmHg. Finally, PAC was obtained as the ratio between RV stroke volume (pulmonary velocity time integral*pulmonary valve annulus area measured from the RV outflow tract diameter) and pulse pressure (obtained from pulmonary and tricuspid regurgitant envelopes) and expressed in ml/mmHg. Results Maximal LA and LV volumes averaged 69±21 ml and 147±47 ml, respectively. The mean value of PCF was 33±12% (range 7% - 58%). Mean 6MWT was 397±162 m. Mean PAC was (3.1±1.1 ml/mmHg). DD grade I, II and III were detected in 38 (63%), 18 (30%) and 4 (7%) of the patients' population, respectively. PCF was independent of LA or LV volumes and EF, but showed a strong direct relation with DD (r=0.62; p&lt;0.0001) and a relevant inverse dependence on Cn (r=−0.48; p=0.0001). For a comparable Cn, dividing patients into tertiles according to 6MWT, it was clear that highest PCF was significantly associated with lowest functional capacity (ANCOVA, figure left). Similarly, dividing patients into tertiles according to PAC, it emerges that highest PCF is significantly associated with most deranged PAC (ANCOVA, figure right), suggesting outmost RV hemodynamic burden. Conclusion PCF is an important parameter to be quantified in HF patients that is dependent on global left heart compliance, being affected by DD, but not LV EF. Furthermore, at a given Cn, PCF is increased in HF patients with lowest functional capacity, likely because RV pulsatile afterload is highest in these subjects.

Creating three dimensional models of the right ventricular outflow tract: influence of contrast, sequence, operator, and threshold.

The use of 3D printed models of the right ventricular outflow tract (RVOT) for surgical and interventional planning is growing and often requires image segmentation of cardiac magnetic resonance (CMR) images. Segmentation results may vary based on contrast, image sequence, signal threshold chosen by the operator, and manual post-processing. The purpose of this study was to determine potential biases and post-processing errors in image segmentation to enable informed decisions. Models of the RVOT and pulmonary arteries from twelve patients who had contrast enhanced CMR angiography with gadopentetate dimeglumine (GPD), gadofosveset trisodium (GFT), and a post-GFT inversion-recovery (IR) whole heart sequence were segmented, trimmed, and aligned by three operators. Geometric agreement and minimal RVOT diameters were compared between sequences and operators. To determine the contribution of threshold, interoperator variability was compared between models created by the same two operators using the same versus different thresholds. Geometric agreement by Dice between objects was high (intraoperator: 0.89-0.95; interoperator: 0.95-0.97), without differences between sequences. Minimal RVOT diameters differed on average by - 1.9 to - 1.3mm (intraoperator) and by 0.4 to 1.4mm (interoperator). The contribution of threshold to interoperator geometric agreement was not significant (same threshold: 0.96 ± 0.06, different threshold: 0.93 ± 0.05; p = 0.181), but minimal RVOT diameters were more variable with different versus constant thresholds (- 9.12% vs. 2.42%; p < 0.05). Thresholding does not significantly change interoperator variability for geometric agreement, but does for minimal RVOT diameter. Minimal RVOT diameters showed clinically relevant variation within and between operators.

The right ventricular outflow tract in pediatric pulmonary hypertension-Data from the European Pediatric Pulmonary Vascular Disease Network.

The right ventricular outflow tract (RVOT) is pivotal for adequate RV function and known to be adversely affected by elevated pulmonary arterial pressure (PAP) in adults with pulmonary hypertension (PH). Aim of this study was to determine the effects of increased RV pressure afterload in children with PH on RVOT size, function, and flow parameters. We conducted a transthoracic echocardiographic study in 51 children with PH (median age: 5.3years; range 1.5months to 18years) and determined the following RVOT variables: RVOT diameter, RVOT velocity time integral (VTI), ratio of tricuspid regurgitation velocity (TRV)/RVOT VTI, and RVOT systolic excursion (SE). In our pediatric PH cohort, the age-specific RVOT diameter z-score was higher compared to normal values. Deviation from normal RVOT diameter values increased with age, disease severity, and New York Heart Association functional class. Significant correlations were found between RVOT diameter and the RV end-diastolic area and right atrial area. The age-specific RVOT VTIz-score values were significantly lower in children with PH vs healthy controls. The TRV/RVOT VTI ratio increased with rising systolic RV pressure, while the RVOT SE was similar between PH children and control subjects. In pediatric PH cohort, the RVOT VTI is decreased, and the TRV/RVOT VTI ratio and the RVOT diameter increased compared to healthy subjects. Assessment of RVOT variables, together with established RV parameters, allows for a comprehensive assessment of global right heart size and performance in children with PH.

Right Ventricular Outflow Tract (RVOT) Changes in Children with an Atrial Septal Defect: Focus on RVOT Velocity Time Integral, RVOT Diameter, and RVOT Systolic Excursion.

Aim of the study was to determine the influence of right heart volume overload in children with atrial septal defect (ASD) on right ventricular outflow tract (RVOT) variables. A prospective study was conducted in 115 children (age range: 2days-18.1years) with a moderate to large ASD. We determined effects of age, body length (BL), body weight (BW), and body surface area (BSA) on the variables RVOT diameter, RVOT velocity time integral (VTI), and RVOT systolic excursion (SE), and tested the predictive value of published normal values for age, BW, BL, and BSA in our ASD patients. In our pediatric ASD patients, the age-specific RVOT diameter (z-score: +2.2, 95% CI: 2.0-2.4, P<0.001) was significantly increased compared to normal values with 54% of our ASD patients having a z-score >2.0. The age-specific RVOT VTI z-score (z-score: +3.6, 95% CI: 3.2-3.9, P<0.001) was significantly increased compared to normal values with 81% of our ASD patients having a z-score >2.0. The age-specific RVOT SE z-score was not increased but slightly lower compared to normal values (z-score: -0.5, 95% CI: -0.7 to -0.3, P<0.001) with 3% of our ASD patients having a z-score >2.0 while 12% of the patients had a z-score <-2. In our study population, we show the RVOT VTI and diameter to be relevant predictors in identifying an enlarged RVOT size and flow in children with moderate to large ASD.

Comparison of patients with early-phase arrhythmogenic right ventricular cardiomyopathy and right ventricular outflow tract ventricular tachycardia

AimsDifferentiation between early-phase arrhythmogenic right ventricular cardiomyopathy (ARVC) and right ventricular outflow tract (RVOT)-ventricular tachycardia (VT) can be challenging, and correct diagnosis is important. We compared electrocardiogram (ECG) parameters and morphological right ventricular (RV) abnormalities and investigated if ECG and cardiac imaging can help to discriminate early-phase ARVC from RVOT-VT patients.Methods and resultsWe included 44 consecutive RVOT-VT (47 ± 14 years) and 121 ARVC patients (42 ± 17 years). Of the ARVC patients, 77 had definite ARVC and 44 had early-phase ARVC disease. All underwent clinical examination, ECG, and Holter monitoring. Frequency of premature ventricular complexes (PVC) was expressed as percent per total beats/24 h (%PVC), and PVC configuration was recorded. By echocardiography, we assessed indexed RV basal diameter (RVD), indexed RVOT diameter, and RV and left ventricular (LV) function. RV mechanical dispersion (RVMD), reflecting RV contraction heterogeneity, was assessed by speckle-tracking strain echocardiography. RV ejection fraction (RVEF) was assessed by cardiac magnetic resonance imaging (CMR). Patients with early-phase ARVC had lower %PVC by Holter and PVC more frequently originated from the RV lateral free wall (both P < 0.001). RVD was larger (21 ± 3 vs. 19 ± 2 mm, P < 0.01), RVMD was more pronounced (22 ± 15 vs. 15 ± 13 ms, P = 0.03), and RVEF by CMR was decreased (41 ± 8 vs. 49 ± 4%, P < 0.001) in early-phase ARVC vs. RVOT-VT patients.ConclusionPatients with early-phase ARVC had structural abnormalities with lower RVEF, increased RVD, and pronounced RVMD in addition to lower %PVC by Holter compared with RVOT-VT patients. These parameters can help correct diagnosis in patients with unclear phenotypes.

Prevalence and risk factors for pulmonary arterial hypertension in end-stage renal disease patients undergoing continuous ambulatory peritoneal dialysis

Background: Pulmonary arterial hypertension (PAH) is a major complication in renal failure patients, but very little information is available on the cardiovascular parameters in these patients. The prevalence and risk factors for PAH were systematically evaluated in patients with end-stage renal diseases (ESRD) undergoing continuous ambulatory peritoneal dialysis (CAPD). Methods: Between January 2010 and January 2014, 177 ESRD patients (85 males and 92 females) undergoing CAPD therapy were recruited. General data, biochemical parameters and echocardiographic findings were collected and PAH risk factors studied. Results: Study participants consisted of 65 patients (36.52%) with PAH (PAH group) and 112 patients without PAH (non-PAH group). The interdialytic weight gain, systolic blood pressure and diastolic blood pressure (DBP), mean arterial pressure and hypertensive nephropathy incidence in the PAH group were significantly higher than the non-PAH group (all p < 0.05). There were significant differences between PAH group and non-PAH group in C-reactive protein-positive rate, N-terminal pro-brain natriuretic peptide (NT-proBNP), hemoglobin, prealbumin and serum albumin levels (all p < 0.05). Compared with non-PAH group, PAH group showed significant increases in right ventricular internal diameter (RVID), right ventricular outflow tract diameter (RVOTD), main pulmonary artery diameter, left atrial diameter (LAD), left ventricular end-diastolic diameter, interventricular septal thickness, left ventricular mass index, early diastolic mitral annulus velocity and valve calcification incidence (all p < 0.05), and decreased left ventricular ejection fraction (LVEF), tricuspid annulus plane systolic excursion (TAPSE) and early diastolic blood flow peak and mitral annulus velocity (E/E’) (all p < 0.05). Logistic regression analysis revealed that DBP, NT-proBNP, LAD, RVID, RVOTD, LVEF, TAPSE and E/E’ are major risk factors for PAH. Conclusion: We observed a high incidence of PAH in ESRD patients undergoing CAPD. Logistic regression analysis revealed that DBP, NT-proBNP, LAD, RVID, RVOTD, LVEF, TAPSE and E/E’ are high-risk factors for PAH in ESRD patients undergoing CAPD.

Application of micro transesophageal echocardiography (micro-TEE) in neonat and infant cardiac surgery

Objective To evaluate the value of phased array probe of transesophageal echocardiography miniature (micro-TEE) in the neonatal and infant cardiac surgery intraoperation. Methods Micro-TEE probe was used in children with weight ≤5 kg undergoing cardiac surgery to detect the atrial and ventricular cavity size, the left and right ventricular outflow tract diameter were detected by transthoracic echocardiography(TTE) 3-7 d after operation, and compared with the measured value immediately after the TEE. Results Before and after intubation, airway index not statistically significant (P>0.05). Preoperative TEE and TTE inspection results were consistent with intraoperative diagnosis. Postoperative TEE measuring intracardiac structural data (each room, chamber size and left and right ventricular outflow tract diameter) and postoperative TTE measurement value representing the difference was not statistically significant(P>0.05). Conclusions Micro TEE intraoperative guardianship of low birth weight infants is safe and feasible, and can supplement and improve the preoperative diagnosis, and can accurately and timely evaluate postoperative curative effect. Key words: Echocardiography, transesopheageal; Infant, low birth weight; Cardiac surgical procedures

Clinical Significance of Epsilon Waves in Arrhythmogenic Cardiomyopathy.

Epsilon waves are hallmark features of arrhythmogenic cardiomyopathy (ACM) but information about their clinical significance is variable. We evaluated epsilon wave prevalence, characteristics, and their clinical significance in an ACM population. Eighty-six unselected patients fulfilling the 2010 Task Force criteria were enrolled. Seventy-six of them were carriers of desmosomal mutations. All subjects were serially evaluated with standard 12-lead ECG and 2-dimensional echocardiography. Epsilon waves were evaluated in all precordial and inferior leads. Novel parameters assessed included their duration and precordial/inferior lead extension. Twenty-five subjects (29%) had epsilon waves that were present in lead V3 and beyond in 9, and in the inferior leads in 7. Epsilon waves were associated with right ventricular outflow tract (RVOT) (P = 0.001) but not RV posterior wall (P = 0.21), RV apex (P = 0.30), or left ventricular (P = 0.94) wall motion abnormalities. Patients with epsilon waves had increased RVOT diameter (P < 0.0001). Extension of epsilon waves in lead V3 and beyond was associated with increased epsilon wave duration (P = 0.002) and RVOT diameter (P = 0.04). The duration of epsilon waves was positively correlated with RVOT diameter (r = 0.70, P = 0.0001). Epsilon waves were also associated with episodes of sustained ventricular tachycardia (P = 0.004) but not with heart failure (P = 0.41) or sudden cardiac death (P = 0.31). Detection of epsilon waves on 12-lead ECG reflects significant RVOT involvement, which was associated with episodes of sustained ventricular tachycardia but not sudden cardiac death.