Assessment of left ventricular dyssynchrony and function using real-time 3-dimensional echocardiography in patients with congenital right heart disease

Analysis of circulating microRNAs in patients with repaired Tetralogy of Fallot with and without heart failure

BACKGROUND

MicroRNAs (miRNAs) are a class of regulatory RNAs that regulate gene expression post-transcriptionally. Little, however, is known on the expression profile of circulating miRNAs in Tetralogy of Fallot (TOF) patients late after surgical repair. In this study, we aimed to identify the specific patterns of circulating miRNAs in blood of patients with repaired, non-syndromic TOF and to assess whether these specific miRNAs may be useful to differentiate patients with and without heart failure.

METHODS

SurePrint™ 8 × 60 K Human v16 miRNA arrays were used to determine miRNA expression profiles in 15 healthy controls and 37 patients after TOF repair of whom 3 had symptomatic right heart failure. The expression levels of selected miRNAs have been validated by quantitative reverse transcription polymerase chain reaction (RT-qPCR). Enrichment analyses of altered miRNA expression were predicted using bioinformatic tools.

RESULTS

Compared with healthy controls, a total of 49, 58 and 77 miRNAs were found to be significantly altered in TOF patients (TOF-all), TOF patients with (TOF-HF) and without symptomatic right heart failure (TOF-noHF) (>2.0-fold change, adjusted P < 0.05), respectively. Three miRNAs namely miR-181d-5p, miR-206 and miR-625-5p were validated by RT-qPCR in all TOF groups. The area under the receiver operating characteristic curve (AUC) for miR-181d-5p, miR-206 and miR-625-5p were 0.987, 0.993 and 0.769 in TOF-all and 0.990, 0.994 and 0.749 in TOF-noHF, respectively. Moreover, expression levels of miR-625-5p, miR-1233-3p and miR-421 were lower in TOF-HF compared to TOF-noHF (P = 0.012).

CONCLUSIONS

Altered expression levels of circulating miRNAs were found in TOF patients late after surgical repair and are different to those seen in the right ventricular myocardium of infants with TOF. Expression levels of miR-421, miR-1233-3p and miR-625-5p are lower in TOF patients with symptomatic right heart failure and thus may indicate disease progression in these patients.

Three-dimensional Echocardiography in Congenital Heart Disease: An Expert Consensus Document from the European Association of Cardiovascular Imaging and the American Society of Echocardiography

Three-dimensional echocardiography (3DE) has become important in the management of patients with congenital heart disease (CHD), particularly with pre-surgical planning, guidance of catheter intervention, and functional assessment of the heart. 3DE is increasingly used in children because of good acoustic windows and the non-invasive nature of the technique. The aim of this paper is to provide a review of the optimal application of 3DE in CHD including technical considerations, image orientation, application to different lesions, procedural guidance, and functional assessment.

Pacing and Defibrillators in Complex Congenital Heart Disease

Device therapy in the complex congenital heart disease (CHD) population is a challenging field. There is a myriad of devices available, but none designed specifically for the CHD patient group, and a scarcity of prospective studies to guide best practice. Baseline cardiac anatomy, prior surgical and interventional procedures, existing tachyarrhythmias and the requirement for future intervention all play a substantial role in decision making. For both pacing systems and implantable cardioverter defibrillators, numerous factors impact on the merits of system location (endovascular versus non-endovascular), lead positioning, device selection and device programming. For those with Fontan circulation and following the atrial switch procedure there are also very specific considerations regarding access and potential complications. This review discusses the published guidelines, device indications and the best available evidence for guidance of device implantation in the complex CHD population.

Assessment of left ventricular dyssynchrony and cardiac function in patients with different pacing modes using real-time three-dimensional echocardiography: Comparison with tissue Doppler imaging

The aim of this study was to evaluate the left ventricular mechanical dyssynchrony (LVMD) and left ventricular dysfunction of patients in AAI, DDD and VVI pacing modes using real-time three-dimensional echocardiography (RT3DE) and tissue Doppler imaging (TDI). The results from the RT3DE and TDI were subsequently compared. Twenty patients with sick sinus syndrome (SSS) who had undergone the implantation of a dual-chamber pacemaker were enrolled in this study and the pacemakers were programmed to AAI, DDD and VVI modes, sequentially. The RT3DE and TDI parameters were obtained following pacing for 24 h in each mode. With RT3DE, we measured the systolic dyssynchrony indices, including Tmsv₁₆-SD%, Tmsv₁₂-SD%, Tmsv₆-SD%, Tmsv₁₆-Dif%, Tmsv₁₂-Dif% and Tmsv₆-Dif%, left ventricular end-diastolic volume (LVEDV), left ventricular end-systolic volume (LVESV) and left ventricular ejection fraction (LVEF), respectively. With TDI, we measured the standard deviation and the maximal difference in time from the QRS onset to the peak systolic velocity for 12 left ventricular myocardial segments, i.e. Ts-SD and Ts-Dif, respectively. The results showed that the Tmsv₁₆-SD% and Ts-SD in the AAI mode were significantly lower than those in the DDD and VVI modes (P<0.05); however, there were no significant differences between the DDD and VVI modes (P>0.05). The LVEF in the AAI, DDD and VVI modes was 63.1±8.9, 58.6±11.2 and 57.9±7.6%, respectively (P>0.05). There were negative correlations between the LVEF and Tmsv₁₆-SD% (r, −0.651; P<0.001) and Ts-SD (r, −0.649; P<0.0001). A moderate correlation (r, 0.698; P<0.0001) was observed between Tmsv₁₆-SD% and Ts-SD. The concordance rate between Tmsv₁₆-SD% and Ts-SD for detecting LVMD was 76%. This study showed that DDD and VVI pacing modes induced significant LVMD and a reduction in LVEF, unlike the AAI pacing mode. RT3DE and TDI were capable of objectively evaluating LVMD; however, each method had certain faults. At present, there is a lack of a uniform standard for assessing LVMD; therefore, the use of a variety of techniques and indices is necessary in order to comprehensively evaluate LVMD in patients with different cardiac pacing modes.

Left ventricular mechanics in repaired tetralogy of Fallot with and without pulmonary valve replacement: analysis by three-dimensional speckle tracking echocardiography

Background

Altered septal curvature and left ventricular (LV) geometry secondary to right ventricular (RV) dilation render two-dimensional assessment of LV mechanics difficult in repaired tetralogy of Fallot (TOF) patients. The novel three-dimensional (3D) speckle tracking echocardiography enables comprehensive evaluation of true 3D LV mechanics.

Methods and Results

Seventy-six patients aged 23.6±8.3 years, 55 with isolated repair (group I) and 21 with subsequent pulmonary valve replacement (group II), and 34 healthy controls were studied. Three-dimensional volume datasets were acquired for assessment of LV global and regional 3D strain, systolic dyssynchrony index (SDI), twist, twist gradient (twist/LV length), and ejection fraction. A global performance index was calculated as (global 3D strain•twist gradient)/SDI. The septal curvature and LV eccentricity were determined from the mid-ventricular short-axis. Compared with controls, group I and II patients had significantly reduced LV global 3D strain, LV twist, twist gradient, septal curvature, and global performance index, and greater LV systolic and diastolic eccentricity and SDI (all p<0.05). All but the four apical LV segments in patients had reduced regional 3D strain compared with controls (all p<0.05). Septal curvature correlated with LV global 3D strain (r = 0.41, p<0.001), average septal strain (r = 0.38, p<0.001), twist (r = 0.32, p<0.001), twist gradient (r = 0.33, p<0.001), and global performance index (r = 0.43, p<0.001).

Conclusions

Adverse 3D LV mechanics as characterized by impaired global and regional 3D systolic strain, mechanical dyssynchrony, and reduced twist is related to reduced septal curvature in repaired TOF patients with and without pulmonary valve replacement.

Usefulness of real-time 3-dimensional echocardiography to identify and quantify left ventricular dyssynchrony in patients with Kawasaki disease

OBJECTIVES

The role of left ventricular (LV) dyssynchrony in Kawasaki disease is unknown. This study sought to establish values for real-time 3-dimensional (3D) echocardiographically derived LV dyssynchrony parameters and identify and quantify LV dyssynchrony in patients with Kawasaki disease.

METHODS

Forty patients hospitalized for Kawasaki disease were analyzed retrospectively, and 40 sex- and age-matched healthy control volunteers were also enrolled. The systolic dyssynchrony index (percentage of the cardiac cycle) from 16 and 12 LV segments on real-time 3D echocardiography was analyzed to calculate LV dyssynchrony (defined as the standard deviation of the time to reach the minimum systolic volume for 16 LV segments) according to a 17-segment model. We analyzed the 3D LV ejection fraction (LVEF), end-diastolic volume, and end-systolic volume in the patients with Kawasaki disease compared to the controls.

RESULTS

The 16-segment systolic dyssynchrony index ± SD was significantly higher in the patients with Kawasaki disease: 2.73% ± 0.96% compared to 2.01% ± 0.85% in the controls (P < .05). The 12-segment systolic dyssynchrony index in the patients with Kawasaki disease was 2.65% ± 0.93% compared to 1.98% ± 0.81% in the controls (P< .05). Patients with Kawasaki disease and an LVEF of less than 50% had a significantly higher systolic dyssynchrony index compared to patients with an LVEF of 50% or greater (2.89% ± 0.79% versus 2.26% ± 0.73%; P < .05). The LVEF measured by echocardiography was decreased in the patients with Kawasaki disease, and global systolic function was impaired. The LVEF measured by a biplane method was sufficiently related to the LVEF measured by echocardiography.

CONCLUSIONS

Real-time 3D echocardiography is a noninvasive and feasible method for identifying and evaluating LV dyssynchrony in children with Kawasaki disease. Left ventricular dyssynchrony is significantly impaired and related to LV systolic function in patients with Kawasaki disease.

Altered diastolic left atrial and ventricular performance in asymptomatic patients after repair of tetralogy of Fallot

We evaluated the interaction of left atrial and ventricular diastolic performance in asymptomatic children and young adults after ToF-repair (n=25). Those young people, as well as 25 age matched healthy children and young adults were examined using non-invasive conventional echocardiography. Regional systolic and diastolic myocardial strain and strain rate in left atrium and ventricle were analysed using 2D-speckle-tracking (Vivid VII, EchoPacGE). We collected planimetric data about the left atrial and ventricular performance during systole (volumetric LVEF, LV-Tei-Index, MV-E/E'-Ratio) and diastole (LAEF, LVEDV, left atrial volume). Registration of right pulmonary-venous inflow-patterns during ventricular systole, diastole and active atrial contraction was used to support assessment of left atrial function. To verify the timing of left atrial contraction and possible electromechanical delay we measured several ECG-related time-intervals. Statistical analysis included Mann-Whitney-U-Test, Bonferroni-Holm-Test and two-tailed Spearman-Correlation. Systolic pulmonary-venous inflow in ToF-patients was not different compared to the controls. Early diastolic pulmonary-venous inflow was significantly higher in ToF-patients as well as the LV-Tei-Index. The MV-E/E'-ratio, which is closely related to LVEDP, was significantly higher in ToF-patients and correlated with the early diastolic pulmonary venous inflow parameters such as the maximum diastolic bloodflow speed. Diastolic left atrial and ventricular strain and strain rate in ToF-patients did not differ from those in the controls. During late diastole there was a significantly premature timing of maximum myocardial strain rate of the interatrial septum and time-ratio of P-wave origin to maximum reverse pulmonary-venous blood flow and the duration of one heart action. Furthermore the maximum late diastolic reverse pulmonary-venous blood flow was significantly higher in ToF-patients. Those observations indicate a premature active left atrial contraction in late diastole in ToF-patients compared to the controls. In asymptomatic young patients after ToF-repair earlier and increased left atrial contraction was found, which may indicate adaptive compensatory mechanisms to overcome latent and asymptomatic altered systolic and diastolic left ventricular performance. Extensive assessment of left atrial parameters including the pulmonary veins should be considered in terms of an entire evaluation of left heart function in patients after ToF-repair.