Echocardiographic parameters of severe pulmonary regurgitation after surgical repair of tetralogy of Fallot

Aims: Reliable evaluation of the severity and consequences of pulmonary regurgita‐ tion (PR) in patients with repaired tetralogy of Fallot (TOF) is crucial to timely identify the need for pulmonary valve intervention. We aimed to identify the accuracy of echocardiographic parameters to differentiate between moderate and severe PR, using phase contrast cardiac magnetic resonance imaging (CMR) as gold standard.
Methods and results: In this cross‐sectional study, 45 TOF patients with both echo‐ cardiographic and CMR measurements of PR were enrolled. All quantitative and semiquantitative echocardiographic measurements such as pressure half time (PHT), Color flow jet width (CFJW), ratio CFJW/right ventricle outflow tract (RVOT) diame‐ ter, PR index and the presence of early termination of the PR jet, end‐diastolic ante‐ grade flow and diastolic backflow in main pulmonary artery (MPA), and PA branches correlated significantly with PR fraction on CMR. Qualitative assessment with color flow on echocardiography overestimated PR Multivariate linear regression analysis identified the ratio of CFJW/RVOT diameter and PHT as independent predictors of PR fraction. Accuracy of echo parameters was tested to differentiate between mild‐ to‐moderate and severe PR Combining different echocardiographic parameters in‐ creased sensitivity and specificity. The addition of diastolic flow reversal in the PA branches to PHT below 167 milliseconds increased the NPV from 87% to 89% and PPV from 62% to 76%.
Conclusions: Comparison with CMR confirms that echocardiographic parameters are reliable in predicting PR severity. Combined measurement of diastolic flow reversal in the pulmonary artery branches and PHT is reliable in the detection of severe PR in the follow‐up of TOF patients.     

Percutaneous pulmonary valve implantation preceded by routine prestenting with a bare metal stent

Objectives: To evaluate the effectiveness and safety of percutaneous pulmonary valve implantation (PPVI) with routine prestenting with a bare metal stent (BMS). Background: PPVI is a relatively new method of treating patients with repaired congenital heart disease (CHD). Results of PPVI performed with routine prestenting have never been reported. Methods: Consecutive patients who underwent PPVI for homograft dysfunction with prestenting with BMS were studied. The schedule of follow‐up assessment comprised clinical evaluation, cardiovascular magnetic resonance, transthoracic echocardiography, and chest X‐ray to screen for device integrity. Results: PPVI was performed with no serious complications in all patients (n = 10, mean age 26.8 ± 4.0 years, 60% males). In nine patients with significant pulmonary stenosis, peak right ventricular outflow tract (RVOT) gradient was reduced from a mean of 80.6 ± 22.7 to 38.8 ± 10.4 mm Hg on the day following implantation (P = 0.001). At 1‐month and 6‐month follow‐ups, mean RVOT gradient was 34.0 ± 9.8 and 32.0 ± 12.2 mm Hg, respectively. In patients with significant pulmonary regurgitation, mean pulmonary regurgitation fraction decreased from 19% ± 6% to 2% ± 1% (P = 0.0008). Relief of RVOT obstruction and restoration of pulmonary valve competence were associated with significant decrease in right ventricular (RV) end‐diastolic and end‐systolic volumes (125.5 ± 48.6 to 109.2 ± 42.9 mL/m²; P = 0.002 and 68.4 ± 41.5 vs. 50.9 ± 40.6 mL/m²; P = 0.001) as well as improvement in RV ejection fraction (48.8% ± 13.1% to 57.6% ± 14.4%; P = 0.003) and New York Heart Association class (P = 0.003). All patients completed 6‐month follow‐up. No stent fractures were observed. Conclusions: PPVI with routine prestenting with BMS is a safe and effective method of treatment in patients with repaired CHD. © 2010 Wiley‐Liss, Inc.     

Nonvolumetric echocardiographic indices of right ventricular systolic function: validation with cardiovascular magnetic resonance and relationship with functional capacity

Purpose: Right ventricular (RV) systolic function as measured by right ventricular ejection fraction (RVEF) has long been recognized as an important predictor of outcome in heart failure patients. The echocardiographic measurement of RV volumes and RVEF is challenging, however, owing to the unique geometry of the right ventricle. Several nonvolumetric echocardiographic indices of RV function have demonstrated prognostic value in heart failure. Comparison studies of these techniques with each other using RVEF as a benchmark are limited, however. Furthermore, the contribution of these various elements of RV function to patient functional status is uncertain. We therefore aimed to: (1) Determine which nonvolumetric echocardiographic index correlates best with RVEF as determined by cardiac magnetic resonance (CMR) imaging (the accepted gold standard measure of RV systolic function) and (2) Ascertain which echocardiographic index best predicts functional capacity. Methods: Eighty‐three subjects (66 with systolic heart failure and 17 healthy controls) underwent CMR, 2D echocardiography, and cardiopulmonary exercise testing for comparison of echocardiographic indices of RV function with CMR RVEF, 6‐minute walk distance and VO_{2 PEAK}. Results: Speckle tracking strain RV strain exhibited the closest association with CMR RV ejection fraction. Indices of RV function demonstrated weak correlation with 6‐minute walk distance, but basal RV strain rate by tissue velocity imaging had good correlation with VO_{2 PEAK}. Conclusion: Strain by speckle tracking echocardiography and strain rate by tissue velocity imaging may offer complementary information in the evaluation of RV contractility and its functional effects. (Echocardiography 2012;29:455‐463)     

The effects of pregnancy on right ventricular remodeling in women with repaired tetralogy of Fallot

Objectives

The aim of this study was to better understand the quantitative volumetric changes associated with pregnancy in women with repaired tetralogy of Fallot (TOF), utilizing sequential cardiovascular magnetic resonance (CMR) imaging.

Background

An increasing number of women with repaired TOF are reaching childbearing age. Limited echocardiographic studies suggest accelerated remodeling of the right ventricle (RV) in women with repaired TOF after pregnancy.

Methods

Sequential CMRs from a group of women with repaired TOF who completed pregnancy and from a matched comparison group of nulliparous women with repaired TOF were evaluated. The two groups were matched according to baseline QRS duration, RV end-diastolic volume (EDV), age at CMR and time between CMRs. Longitudinal change of CMR parameters was compared between the groups.

Results

Thirteen women (mean age 26.6 ± 7.4 years) with repaired TOF who completed pregnancy and 26 nulliparous women with repaired TOF (mean age 22.6 ± 8.0 years) were included in this analysis. The rate of increase of RV EDV in the pregnancy group was higher than the comparison group (4.1 ± 1.1 ml/m²/year vs. 1.6 ± 0.6 ml/m²/year, p = 0.07). RV EF did not change significantly in either group. No definitive interaction between degree of pulmonary regurgitation and increase of RV EDV was identified.

Conclusions

Women with repaired TOF who have completed pregnancy appear to experience an accelerated rate of right ventricular remodeling, defined as an increase in end-diastolic volume; however RV systolic function does not deteriorate. Further investigations with a prospective study design, larger cohorts, and longer follow-up are needed to confirm these initial observations.     

Right atrial size relates to right ventricular end-diastolic pressure in an adult population with congenital heart disease

Aim: Noninvasive markers of right ventricular (RV) diastolic dysfunction are limited by their lack of reproducibility and accuracy. We tested the hypothesis that right atrial (RA) size measured by echocardiography was correlated to invasive parameters of RV diastolic filling. Methods and Results: We studied 31 consecutive adult patients with congenital heart disease. From 2D echocardiography images, we measured maximal RA long‐axis and short‐axis lengths, area and volume. We compared each of these measures to right ventricular end‐diastolic pressure (RVEDP) and mean right atrial pressure (mRAP) measured by right heart catheterization. RA long‐axis, short‐axis, area, and volume correlated significantly with RVEDP (r = 0.78, P < 0.001; r = 0.61, P < 0.001; r = 0.79, P < 0.001; and r = 0.75, P < 0.001, respectively) and mRAP (r = 0.66, P < 0.001; r = 0.56, P = 0.002; r = 0.70, P < 0.001; r = 0.68, P < 0.001, respectively). Single cut points for each echocardiographic parameter demonstrated reasonable accuracy to rule‐in and rule‐out RVEDP ≥7 mm Hg (sensitivity = 74%, specificity = 82%, positive LR = 4.1, negative LR = 0.32 for RA long‐axis of 49 mm; sensitivity = 89%, specificity = 82%, positive LR = 4.9, negative LR = 0.12 for RA area of 14 cm²; sensitivity = 89%, specificity = 82%, positive LR = 4.9, negative LR = 0.13 for RA volume of 37 mL). Conclusion: RA size measured by echocardiography is strongly correlated to invasive parameters of RV diastolic filling and predicts high RV end‐diastolic pressure. (Echocardiography 2011;28:109‐116)     

The role of echocardiography for quantitative assessment of right ventricular size and function in adults with repaired tetralogy of Fallot

Background: Quantitative assessment of right ventricular (RV) systolic function by echocardiography is challenging in patients with congenital heart disease because of the complex geometry of the RV and the iatrogenic structural abnormalities resulting from prior cardiac surgeries. The purpose of this study was to determine the correla‐ tion between echocardiographic indices of RV systolic function and cardiac magnetic resonance imaging (CMRI) derived RV ejection fraction (RVEF) in adults with repaired tetralogy of Fallot (TOF).
Methods: Quantitative assessment of RV function was performed with RV tissue Doppler systolic velocity (RV s'), tricuspid annular plane systolic excursion (TAPSE), and fractional area change (FAC). These echocardiographic indices were compared to RVEF from CMRI performed on the same day as echocardiogram.
Results: Of 209 patients, the mean RV FAC was 39 ± 9%, TAPSE was 18 ± 4 mm, RV s' was 10 ± 2 cm/s, and RVEF was 40 ± 10%. There was a good correlation be‐ tween TAPSE and RVEF (r = 0.79, P < .001), good correlation between RV s' and RVEF (r = 0.71, P < .001), and modest correlation between FAC and RVEF (r = 0.66, P < .001). TAPSE < 17 mm effectively discriminated between patients with RV systolic dysfunc‐ tion defined as RVEF < 47% (sensitivity 81%, specificity 79%, area under the curve [AUC] 0.805). FAC < 40% was associated with RVEF < 47% (sensitivity 72%, specificity 63%, AUC 0.719). RV s' < 11 cm was associated with RVEF < 47% (sensitivity 83%, specificity 68%, AUC 0.798).
Conclusion: Despite the structural and functional abnormalities of the RV in patients with repaired TOF, quantitative assessment of RV systolic function by echocardiog‐ raphy is feasible and had good correlation with CMRI‐derived RVEF.     

Pulmonary Regurgitation after Tetralogy of Fallot Repair: A Diagnostic and Therapeutic Challenge

Background:

Pulmonary regurgitation is the key hemodynamically significant lesion in repaired tetralogy of Fallot contributing to progressive right ventricular (RV) dilatation and biventricular dysfunction. The timing for pulmonary valve replacement remains a controversial topic, and the decision to intervene depends on assessment of RV size and RV function.

Objectives:

This review aims to discuss the echocardiographic techniques that can be used to assess patients with pulmonary regurgitation after the repair of tetralogy of Fallot defect. While cardiac magnetic resonance (CMR) imaging is the clinical reference method, there is an important role of echocardiography in identifying patients with significant pulmonary regurgitation and assessing the RV size and function. The different echocardiographic techniques that can be used in this context are discussed. Newer techniques for assessing RV size and function include three-dimensional (3D) echocardiography, tissue Doppler and strain imaging. 3D RV volumetric reconstruction based on two-dimensional imaging is a promising new technique that could potentially replace CMR for RV volumetric assessment.

Conclusions:

Developments in echocardiographic techniques provide new insights into the impact of pulmonary regurgitation on RV structure and function. Echocardiography and CMR are complementary modalities and further research is required to define the optimal use of both techniques for this indication.     

Feasibility of right ventricular longitudinal systolic function evaluation with transthoracic echocardiographic indices derived from tricuspid annular motion: a preliminary study in acute respiratory distress syndrome

Introduction: Assessment of right ventricular (RV) function in patients with acute respiratory distress syndrome (ARDS) remains challenging. Transthoracic echocardiographic (TTE) indices based on longitudinal systolic RV function are now considered as a reliable evaluation of RV function. We investigated feasibility of two methods in ARDS patients. Methods: Prospective observational study. TTE was performed after 12–36 hours of mechanical ventilation. Feasibility of tricuspid annular motion (S_t), tricuspid annular plane systolic excursion (TAPSE) was compared to usual two‐dimensional (2D) study: fractional area change (RV_FAC) and ratio of right to left ventricular end‐diastolic area (RVEDA/LVEDA). Results: Fifty patients were investigated, with TTE possible in all but two patients. Feasibility was 62% for RV_FAC, 72% for RVEDA/LVEDA, and 96% for TAPSE and S_t. RV dilatation (RVEDA/LVEDA ≥0.60) was found in 16 patients, including 4 patients with acute cor pulmonale. A longitudinal RV dysfunction (TAPSE < 12 mm or S_t < 11.5 cm/sec) was suspected in 30% of patients. Relation between both longitudinal indices was modest (r²= 0.36, P < 0.001). TAPSE (but not S_t) was found poorly related to RV_FAC (r²= 0.27, P = 0.03). Both indices were related to LV function (S_t: r²= 0.27, TAPSE: r²= 0.17, both P < 0.05). Conclusion: Despite a superior feasibility than 2D study, our results suggest that both indices may not bring identical information to echo study. TAPSE may be more adapted to ICU use than S_t. Both should be further investigated in terms of analysis of RV function and ventricular interdependence. Their relations with LV function may limit their use as sole markers of RV function in this population. (Echocardiography 2012;29:513‐521)     

Right atrial area and right ventricular outflow tract akinetic length predict sustained tachyarrhythmia in repaired tetralogy of Fallot

Aims

Repaired tetralogy of Fallot (rtoF) patients are at risk of atrial or ventricular tachyarrhythmia and sudden cardiac death. Risk stratification for arrhythmia remains difficult.We investigated whether cardiac anatomy and function predict arrhythmia.

Methods

One-hundred-and-fifty-four adults with rtoF, median age 30.8 (21.9–40.2) years, were studied with a standardised protocol including cardiovascular magnetic resonance (CMR) and prospectively followed up over median 5.6 (4.6–7.0) years for the pre-specified endpoints of new-onset atrial or ventricular tachyarrhythmia (sustained ventricular tachycardia/ventricular fibrillation).

Results

Atrial tachyarrhythmia (n = 11) was predicted by maximal right atrial area indexed to body surface area (RAAi) on four-chamber cine-CMR (Hazard ratio 1.17, 95% Confidence Interval 1.07–1.28 per cm²/m²; p = 0.0005, survival receiver operating curve; ROC analysis, area under curve; AUC 0.74 [0.66–0.81]; cut-off value 16 cm²/m²). Atrial arrhythmia-free survival was reduced in patients with RAAi ≥ 16 cm²/m² (logrank p = 0.0001). Right ventricular (RV) restrictive physiology on echocardiography (n = 38) related to higher RAAi (p = 0.02) and had similar RV dilatation compared with remaining patients.Ventricular arrhythmia (n = 9) was predicted by CMR RV outflow tract (RVOT) akinetic area length (Hazard ratio 1.05, 95% Confidence Interval 1.01–1.09 per mm; p = 0.003, survival ROC analysis, AUC 0.77 [0.83–0.61]; cut-off value 30 mm) and decreased RV ejection fraction (Hazard ratio 0.93, 95% Confidence Interval 0.87–0.99 per %; p = 0.03). Ventricular arrhythmia-free survival was reduced in patients with RVOT akinetic region length > 30 mm (logrank p = 0.02).

Conclusion

RAAi predicts atrial arrhythmia and RVOT akinetic region length predicts ventricular arrhythmia in late follow-up of rtoF. These are simple, feasible measurements for inclusion in serial surveillance and risk stratification of rtoF patients.     

Effects of Chronic Severe Pulmonary Regurgitation and Percutaneous Valve Repair on Right Ventricular Geometry and Contractility Assessed by Tissue Doppler Echocardiography

Introduction: Pulmonary regurgitation (PR) following repair of right ventricular (RV) outflow obstruction is related to slowly progressive RV dilatation and heart failure and will eventually require surgical intervention, but optimal timing of pulmonary valve replacement is challenging. Tissue Doppler based quantification of RV contractility may offer additional information in the management of these patients. Methods: In a porcine animal model free PR was induced by percutaneous stenting of the pulmonary valve orifice (N = 23). After 1, 2, or 3 months of free PR percutaneous pulmonary valve replacement (PPVR) was performed. Tissue Doppler derived measures of global and regional myocardial contractility were obtained by transthoracic echocardiography, and compared to a sham‐operated control group (N = 9). Results: Free PR is associated with RV dilatation (RV end‐diastolic area increased from 15 ± 3 to 23 ± 7 cm²/m², P < 0.0001) and a decrease in RV fractional area change from 62 ± 10% to 57 ± 12%, P = 0.08, with no impact of duration of free PR. The isovolumic acceleration, regional strain, and strain rate were unchanged after free PR and after PPVR. No consistent relation of echocardiographic measures of contractility and response to PPVR could be identified. Conclusion: Echocardiographic measures of RV contractility remained unchanged, despite significant RV remodeling following chronic PR and PPVR persistently induced significant recovery in the majority of the animals. These results may imply that Tissue Doppler based measures of RV contractility may not be sufficiently sensitive to be a suitable adjunct to conventional echocardiography in the follow‐up of patients with free PR in order to optimize timing of valve replacement. (Echocardiography 2010;27:854‐863)     

Variability in Surgical Referral Patterns for Pulmonary Valve Replacement in Adults with Repaired Tetralogy of Fallot

Background. Individuals with repaired tetralogy of Fallot (TOF) comprise a substantial proportion of the current adult congenital heart disease population. Pulmonary regurgitation (PR) is one of the most prevalent postoperative sequelae, but timing of pulmonary valve replacement (PVR) in the asymptomatic TOF patient remains controversial. Objective. We sought to explore thresholds for PVR referral among adult congenital physicians. Methods. Physicians attending an international adult congenital cardiac disease conference were given a survey focusing on PVR referral patterns for the asymptomatic individual with repaired TOF. Survey questions related to an asymptomatic adult with repaired TOF, at least moderate PR, and varying degrees of right ventricular (RV) dilation and RV dysfunction. Results. A total of 128 surveys were completed. Nine percent did not feel that PVR was indicated in the asymptomatic patient. Of those practitioners who felt that PVR was indicated, many [(69%, [74/107]) relied on RV end‐diastolic volumes (RVEDV) to guide decision making. Fewer relied on RVEDV for surgical referral as RV ejection fraction (EF) decreased. RVEDV thresholds for PVR referral varied depending on the RV function: with normal RVEF, 180 cc/m² was the most commonly used cutoff; if RV dysfunction was significant, 150 cc/m² was the threshold most often cited. Physicians who utilized RV volumes to guide decision making tended to work in a tertiary care setting (P= 0.008). Conclusions. PVR referral patterns for an asymptomatic TOF patient with significant PR and important RV dilation are variable among adult congenital cardiologists. Uncertainty regarding thresholds for PVR referral underscores the need for further study of this important issue.     

Effects of left ventricular function on the exercise capacity in patients with repaired tetralogy of Fallot

Background: Tissue Doppler imaging has been recently used to evaluate ventricular function. Peak oxygen uptake (V^?O₂peak) has been demonstrated as a predictor for death in adults with repaired tetralogy of Fallot (TOF). The aim of this study was to determine which Doppler parameters correlated with V^?O₂peak in patients with repaired TOF. Method and Results: Doppler echocardiography, tissue Doppler imaging, and exercise test were performed in 30 patients with TOF after surgical repair. In 30 patients with repaired TOF (median age 14 years, range 9–25 years), 11 patients (37%) were female. Seven patients (median age 12 years) had normal left ventricular diastolic function, whereas the rest of the patients were classified as diastolic dysfunction grade II (median age 15 years; n = 15) and III and IV (median age 18 years; n = 8). The oxygen uptake at anaerobic threshold (V^?O_2AT) and peak exercise in patients with left ventricular diastolic dysfunction was significantly lower than that in those with normal diastolic function. Also, V^?O_2AT and V^?O₂peak in patients with diastolic dysfunction grade III and IV were significantly lower than that in those with diastolic dysfunction grade II. Left ventricular early diastolic myocardial velocity was most closely correlated to V^?O₂peak (r = 0.51; P = 0.005). Peak early ventricular filling velocity to early diastolic myocardial velocity ratio was significantly correlated with V^?O₂peak (r =?0.50; P = 0.006). Conclusion: Left ventricular diastolic dysfunction is correlated with V^?O₂peak. Left ventricular diastolic function should be a routine echocardiographic assessment in patients with repaired TOF. (Echocardiography 2011;28:1019‐1024)     

Value of the surface electrocardiogram in detecting right ventricular dilatation in the presence of left bundle branch block

Approximately 20% of patients with heart failure have left bundle branch block (LBBB) on surface electrocardiogram (ECG). In this group of patients, detection of right ventricular (RV) dilatation on standard ECG can be of clinical relevance because RV enlargement is an important prognostic marker. Consequently, the aim of this study was to evaluate diagnostic accuracy for several electrocardiographic criteria in determining significant RV dilatation in these patients. Standard 12-lead ECGs were obtained in 173 patients with heart failure and known LBBB. From the ECG, 3 criteria for RV dilatation were defined: presence of terminal positivity in lead aVR (late R wave in lead aVR), low voltage (<0.6 mV) in all extremity leads, and an R/S ratio <1 in lead V(5). In addition, all patients underwent comprehensive echocardiographic evaluation including assessment of RV dimensions. Measurements were performed blinded to electrocardiographic results. Significant RV dilatation was defined as an RV base-to-apex length ≥ 86 mm or an RV diastolic area ≥ 33 cm(2). Eighty-six patients (50%) had a late R wave in lead aVR, 36 patients (21%) had low voltage in extremity leads, and 67 patients (39%) had an R/S ratio <1 in lead V(5). An RV base-to-apex length ≥ 86 mm was present in 67 patients (39%), and 62 patients (36%) had an RV diastolic area ≥ 33 cm(2). Any combination of 2 to 3 positive criteria could predict an RV base-to-apex length ≥ 86 mm with a positive predictive value of 89% and a negative predictive value of 88%. Similarly, an RV diastolic area ≥ 33 cm(2) was predicted with a positive predictive value of 80% and a negative predictive value of 88%. In conclusion, combining 2 to 3 distinct electrocardiographic criteria allows for accurate detection of RV dilatation in patients with heart failure and LBBB.     

Systolic Right Ventricular Function in Children and Young Adults with Pulmonary Artery Hypertension Secondary to Congenital Heart Disease and Tetralogy of Fallot: Tricuspid Annular Plane Systolic Excursion (TAPSE) and Magnetic Resonance Imaging Data

Objective. The tricuspid annular plane systolic excursion (TAPSE), as echocardiographic index to assess right ventricular (RV) systolic function, has not been investigated thoroughly in children and young adults with tetralogy of Fallot (TOF) and pulmonary artery hypertension secondary to congenital heart disease (PAH‐CHD). Patients. TAPSE values of 49 patients with PAH‐CHD and 156 patients with TOF were compared with age‐matched normal subjects. TAPSE values were also compared with RV ejection fraction (RVEF) and RV indexed end‐diastolic volume (RVEDVi) determined by magnetic resonance imaging in PAH‐CHD and TOF patients. Results. Patients with a PAH‐CHD showed a positive correlation between TAPSE with RVEF (r= 0.81; P < 0.001) and a negative correlation between TAPSE with RVEDVi (r=?0.67; P < 0.001). Similarly, in our TOF patients, a positive correlation between TAPSE with RVEF (r= 0.65; P < 0.001) and a negative correlation between TAPSE with RVEDVi (r=?0.42; P < 0.001) was seen. Conclusions. Significant pressure overload in PAH‐CHD patients and volume overload in TOF patients lead to a decreased systolic RV function, determined by TAPSE and magnetic resonance imaging and to increased RVEDVi values, determined by MRI, with time.     

Electrocardiographic QRS Duration Reflects Right Ventricular Remodeling in Patients Undergoing Corrective Surgery for Isolated Tricuspid Regurgitation: A Comparative Study with Cardiac Magnetic Resonance Imaging

Background:

The role of electrocardiogram (ECG) is unclear for the longitudinal follow‐up of patients who undergo corrective surgery for isolated severe tricuspid regurgitation (TR).

Hypothesis:

This study sought to investigate the usefulness of changes in QRS duration of ECG after TR surgery in predicting right ventricular (RV) reverse remodeling as determined by cardiac magnetic resonance imaging (CMR).

Methods:

We enrolled 30 consecutive TR patients (27 women, aged 57.8 ± 9.6 years) who had undergone prior left‐sided valve surgery. A computer‐assisted analysis was performed for objective calculation of QRS duration before and after surgery.

Results:

At a median CMR follow‐up of 27.5 months postsurgery, QRS duration was cut by 14.6%, from 110.4 ± 14.6 msec to 96.9 ± 11.9 msec (P < 0.001), while CMR showed a decrease in RV end‐diastolic volume index (RV‐EDVI) from 179.5 ± 59.7 to 119.1 ± 30.4 mL/m² (P < 0.001). QRS duration correlated significantly with RV‐EDVI and RV end‐systolic volume index (r = 0.65, P < 0.001 and r = 0.53, P < 0.001, respectively), and a percent change in QRS duration was significantly correlated with a percent change in RV‐EDVI (r = 0.40, P = 0.03). When significant RV reverse remodeling was defined as a reduction in RV‐EDVI ≥20% following TR surgery, the sensitivity and specificity for significant RV reverse remodeling were 75% and 78%, respectively, with a 9% reduction in QRS duration (P = 0.01, area underneath the receiver operator curve [AUC] = 0.81).

Conclusions:

The extent of changes in postoperative QRS duration can be used as a useful, inexpensive, and simple index reflecting the occurrence of significant RV reverse remodeling in patients undergoing corrective TR surgery. Clin. Cardiol. 2012 doi: 10.1002/clc.22030 First two authors equally contributed to this work. This study was supported in part by grants from the Korea Health 21 R&D Project, Ministry of Health and Welfare, Republic of Korea (A090064) and Leading Foreign Research Institute Recruitment Program through the National Research Foundation of Korea (NRF) funded by the Ministry of Education, Science and Technology (MEST) (0640‐20100001). The authors have no funding, financial relationships, or conflicts of interest to disclose.     

Infundibular sparing versus transinfundibular approach to the repair of tetralogy of Fallot

Introduction: The right ventricular infundibular sparing approach (RVIS) to the repair of tetralogy of Fallot (TOF) avoids a full-thickness ventricular incision, typically utilized in the transinfundibular (TI) method.
Methods: We performed a retrospective, age-matched cohort study of patients who underwent RVIS at Texas Children’s Hospital or TI at Children’s Hospital Medical Center in Nebraska and subsequently underwent cardiac magnetic resonance imaging (CMR). We compared right ventricular end-diastolic and systolic volumes indexed to body surface area (RVEDVi and RVESVi) and right ventricular ejection fraction (RVEF) as primary endpoints. Secondary endpoints were indexed left ventricular diastolic and systolic volume (LVEDVi and LVESVi), left ventricular ejection fraction (LVEF), right ventricular (RV) sinus ejection fraction (EF) and RV outflow tract EF (RVOT EF).
Results: Seventy-nine patients were included in the analysis; 40 underwent RVIS and 39 underwent TI repair. None of the patients in the TI repair group had an initial palliation with a systemic to pulmonary arterial shunt compared to seven (18%) in the RVIS group (P < .01). There was no appreciable difference in RVEDVi (122 ± 29 cc/ m² vs 130 ± 29 cc/m² , P = .59) or pulmonary regurgitant fraction (40 ± 13 vs 37 ± 18, P = .29) between the RVIS and TI groups. Compared to the TI group, the RVIS group had higher RVEF (54 ± 6% vs 44 ± 9%, P < .01), lower RVESV (57 ± 17 cc/m² vs 67 ± 25 cc/m² , P = .03), higher LVEF (61 ± 11% vs 54 ± 8%, P < .01), higher RVOT EF (47 ± 12% vs 41 ± 11%, P = .03), and higher RV sinus EF (56 ± 5% vs 49 ± 6%, P < .01).
Conclusions: In this selected cohort, patients who underwent RVIS repair for TOF had higher right and left ventricular ejection fraction compared to those who underwent TI repair.     

Echocardiographic findings in patients meeting task force criteria for arrhythmogenic right ventricular dysplasia: new insights from the multidisciplinary study of right ventricular dysplasia

OBJECTIVES: The purpose of this study was to quantify the echocardiographic abnormalities in probands who were newly diagnosed with arrhythmogenic right ventricular dysplasia (ARVD). BACKGROUND: The diagnosis of ARVD remains challenging. The Multidisciplinary Study of Right Ventricular Dysplasia was initiated to characterize the cardiac structural, clinical, and genetic aspects of ARVD. METHODS: Detailed echocardiograms were performed in 29 probands and compared with echoes from 29 normal control patients matched for age, gender, body size, and year of echo. Right atrial (RA) and right ventricular (RV) chamber dimensions, RV regional function, and the presence of morphologic abnormalities (hyper-reflective moderator band, trabecular derangement, and sacculations) were assessed. The RV systolic function was calculated as RV fractional area change (FAC). RESULTS: The RV dimensions were significantly increased, and RV FAC was significantly decreased in probands versus control patients (27.2 +/- 16 mm vs. 41.0 +/- 7.1 mm, p = 0.0003). The right ventricular outflow tract (RVOT) was the most commonly enlarged dimension in ARVD probands (37.9 +/- 6.6 mm) versus control patients (26.2 +/- 4.9 mm, p < 0.00001). A RVOT long-axis diastolic dimension >30 mm occurred in 89% of probands and 14% of controls. The RV morphologic abnormalities were present in many probands (trabecular derangement in 54%, hyper-reflective moderator band in 34% and sacculations in 17%) but not in controls. CONCLUSIONS: Probands with ARVD have significant RA and RV enlargement and decreased RV function, which can be easily assessed on standard echocardiographic imaging. These parameters should be measured when ARVD is suspected and compared with normal values.     

Long‐Term Outcome in Asymptomatic Patients with Severe Aortic Regurgitation,Normal Left Ventricular Ejection Fraction,and Severe Left Ventricular Dilatation

Background: Although the guidelines consider severe left ventricular (LV) dilatation a class IIaC indication for surgery in asymptomatic patients with severe aortic regurgitation (AR) and normal LV function, the optimal management remains controversial. We aimed to assess the LV enlargement, hypertrophy and function, and the outcomes in these patients by the presence of severe LV dilatation at baseline. Methods: From our 20‐year database, we identified all asymptomatic patients with severe AR and LV ejection fraction (EF) >50% and ≥2 echocardiograms ≥1 year apart. LV end‐diastolic diameter >70 mm or LV end‐systolic diameter >50 mm or LV end‐systolic diameter index >25 mm/m² defined severe LV dilatation. A composite end point included onset of symptoms or LV dysfunction. Results: Eighty‐four patients (52 ± 18 years, 61 men) were enrolled and followed‐up for 7.1 ± 5.1 years. Two groups were defined: 22 patients with and 62 patients without severe LV dilatation at baseline. The progression of LV dilatation and hypertrophy, and the LVEF at last exam were similar in both groups. Twelve of 22 and 34 of 62 patients (P = 0.59) reached the end point. Vasodilators did not modify the progression of LV enlargement/hypertrophy. Ten of 22 and 25 of 62 patients (P = 0.45) underwent surgery and had similar postoperative LV diameters, mass, EF. Conclusions: The progression of LV enlargement/hypertrophy and outcomes in asymptomatic patients with severe AR, normal LV function, and severe LV dilatation or the postoperative LV parameters were not influenced by the severe LV dilatation, suggesting that a close follow‐up could delay surgery in this population. (Echocardiography 2010;27:915‐922)     

The impact of body mass index on right ventricular systolic functions in normal and mildly obese healthy patients: a velocity vector imaging study

Background: Increasing prevalence of obesity is a significant problem in Western countries. Obesity has many effects on cardiovascular structure, function, and hemodynamics. Our aim was to compare the impact of body mass index (BMI) on right ventricular (RV) functions among healthy subjects with conventional echocardiography, tissue Doppler imaging (TDI), and velocity vector imaging (VVI). Methods: Eighty‐one healthy subjects divided into three group according to their BMI. All subjects were evaluated by conventional echocardiography, TDI, and VVI. A full polysomnogram were performed in subjects with BMI ≥ 30 km/m². Results: RV end‐diastolic and end‐systolic diameters of patients in these three groups were similar (P > 0.05). There were no differences between each group in RV outflow tract fractional shortening (P = 0.52) and tricuspid annular plane systolic excursion (P = 0.94). No correlation observed between BMI and RV systolic parameters obtained with TDI. Longitudinal peak systolic strain and SRs were similar in all groups through each segment (P > 0.05) Conclusion: The results of our study show no changes in the RV functions in obese and overweight who were otherwise healthy subjects. We also revealed a significant correlation between BMI and left ventricular diameters and wall thickness but no relation with RV diameters or functions. (Echocardiography 2011;28:746‐752)     

Evaluation of the peri-strut low intensity area following sirolimus- and paclitaxel-eluting stents implantation: insights from an optical coherence tomography study in humans

Background

In the past 5 years a few number of studies and case reports have come out focusing on biventricular (BiV) stimulation for treatment of congenital heart disease related ventricular dysfunction. The few available studies include a diverse group of pathophysiological entities ranging from a previously repaired tetralogy of Fallot (TOF) to a functional single ventricle anatomy. Patient's status is too heterogeneous to build important prospective study. To well understand the implication of prolonged electromechanical dyssynchrony we performed a chronic animal model that mimics essential parameters of postoperative TOF.

Methods

Significant pulmonary regurgitation, mild stenosis, as well as right ventricular outflow tract (RVOT) scars were induced in 15 piglets to mimic repaired TOF. 4 months after hemodynamics and dyssynchrony parameters were compared with a control group and with a population of symptomatic adult with repaired TOF.

Results

Comparing the animal model with the animal control group on echocardiography, RV dilatation, RV and LV dysfunction, broad QRS complex and dyssynchrony were observed on the animal model piglets. Moreover, epicardial electrical mapping showed activation consistent with a right bundle branch block. The animal models displayed the same pathophysiological parameters as the post TOF repair patients in terms of QRS duration, pulmonary regurgitation biventricular dysfunction and dyssynchrony.

Conclusion

This chronic swine model mimics electromechanical ventricular activation delay, RV and LV dysfunction, as in adult population of repair TOF. It does appear to be a very useful and interesting model to study the implication of dyssynchrony and the interest of resynchronization therapy in TOF failing ventricle.