Stefan Orwat

Left Ventricular Longitudinal Function Predicts Life-Threatening Ventricular Arrhythmia and Death in Adults With Repaired Tetralogy of Fallot

Background— Sudden cardiac death and life-threatening ventricular arrhythmia remain a concern in adult patients with repaired tetralogy of Fallot. Longitudinal left ventricular (LV) function is sensitive in detecting early myocardial damage and may have prognostic implications in this setting. Methods and Results— We included 413 tetralogy of Fallot patients (age, 36±13 years; QRS duration, 148±27 milliseconds; LV ejection fraction, 55±10%). A composite end point of sudden cardiac death/life-threatening ventricular arrhythmia (sustained ventricular tachycardia, resuscitated sudden cardiac death, or appropriate implantable cardioverter-defibrillator discharge) was used. During a median follow-up of 2.9 years, 5 patients died suddenly, 9 had documented sustained ventricular tachycardia, and another 5 had appropriate implantable cardioverter-defibrillator shocks. On univariate Cox analysis, QRS duration (hazard ratio [HR], 1.02 per 1 ms; P=0.046), right atrial area (HR, 1.05 per 1 cm2; P=0.02), right ventricular fractional area change (HR, 0.94 per 1%; P=0.02), right ventricular outflow tract diameter (HR, 1.08 per 1 mm; P=0.01), mitral annular plane systolic excursion (HR, 0.84 per 1 mm; P=0.03), and LV global longitudinal 2-dimensional strain (HR, 0.87 per 1%; P=0.03) were related to the combined end point. On bivariable analysis, mitral annular plane systolic excursion and LV global longitudinal 2-dimensional strain were related to outcome independently of QRS duration (P=0.002 and P=0.01, respectively). In addition, a combination of echocardiographic variables, including right atrial area, right ventricular fractional area change, and LV global longitudinal 2-dimensional strain or mitral annular plane systolic excursion, was also found to be significantly related to outcome (P<0.001; c statistic, 0.70). Conclusions— LV longitudinal dysfunction was associated with greater risk of sudden cardiac death/life-threatening ventricular arrhythmias. In combination with echocardiographic right heart variables, also available from routine echocardiography, these measures provide important outcome information and should be considered a useful adjunct to established markers such as QRS duration in the estimation of prognosis in this challenging population.

Right ventricular–left ventricular interaction in adults with Tetralogy of Fallot: A combined cardiac magnetic resonance and echocardiographic speckle tracking study

OBJECTIVES To assess ventricular dysfunction and ventricular interaction after repair of Tetralogy of Fallot (ToF) employing echocardiography speckle-tracking and cardiac magnetic resonance imaging (CMR). BACKGROUND Severe pulmonary regurgitation and right ventricular (RV) dysfunction are common after repair of ToF and may also affect the shape and function of the left ventricle (LV). Recent studies suggest that LV dysfunction may be of particular prognostic value. METHODS AND RESULTS Twenty-one consecutive adults with repaired ToF (15 male, mean age 38 ± 11 years, 7 with severe PR) underwent a comprehensive echocardiographic exam including speckle-tracking analysis, CMR and cardiopulmonary exercise testing. Twenty-one subjects without relevant heart disease served as controls. Echocardiographically measured RV diameters correlated with RV volumes obtained from CMR (r=0.63; p=0.006). In addition, a close correlation was found between RV and LV function on CMR (r=0.74, p=0.002), speckle-tracking LV and RV peak longitudinal 2D strain (r=0.66, p=0.003) and mitral and tricuspid annular plain systolic excursion (r=0.71, p=0.0003). While LV ejection fraction was normal in the majority of patients and not different from controls, LV longitudinal strain was significantly reduced in ToF patients (-16.5 ± 3.3 vs. -20.5 ± 2.7%, p=0.0001). CONCLUSION Left and right ventricular function both by CMR and speckle-tracking is interrelated in adults with repaired ToF. Despite normal LV ejection fraction, 2D longitudinal strain is significantly reduced in ToF patients, suggesting subclinical LV myocardial damage. Considering the potential prognostic value of LV dysfunction in ToF, this measurement may gain importance and should be included in future outcome studies.

Quantification of biventricular myocardial function using cardiac magnetic resonance feature tracking, endocardial border delineation and echocardiographic speckle tracking in patients with repaired tetralogy of fallot and healthy controls

BackgroundParameters of myocardial deformation have been suggested to be superior to conventional measures of ventricular function in patients with tetralogy of Fallot (ToF), but have required non-routine, tagged cardiovascular magnetic resonance (CMR) techniques. We assessed biventricular myocardial function using CMR cine-based feature tracking (FT) and compared it to speckle tracking echocardiography (STE) and to simple endocardial border delineation (EBD). In addition, the relation between parameters of myocardial deformation and clinical parameters was assessed.MethodsOverall, 28 consecutive adult patients with repaired ToF (age 40.4 ± 13.3 years) underwent standard steady-state-free precession sequence CMR, echocardiography, and cardiopulmonary exercise testing. In addition, 25 healthy subjects served as controls. Myocardial deformation was assessed by CMR based FT (TomTec Diogenes software), CMR based EBD (using custom written software) and STE (TomTec Cardiac Performance Analysis software).ResultsFeature tracking was feasible in all subjects. A close agreement was found between measures of global left (LV) and right ventricular (RV) global strain. Interobserver agreement for FT and STE was similar for longitudinal LV global strain, but FT showed better inter-observer reproducibility than STE for circumferential or radial LV and longitudinal RV global strain. Reproducibility of regional strain on FT was, however, poor. The relative systolic length change of the endocardial border measured by EBD yielded similar results to FT global strain. Clinically, biventricular longitudinal strain on FT was reduced compared to controls (P < 0.0001) and was related to the number of previous cardiac operations. In addition, FT derived RV strain was related to exercise capacity and VE/VCO2-slope.ConclusionsAlthough neither the inter-study reproducibility nor accuracy of FT software were investigated, and its inter-observer reproducibility for regional strain calculation was poor, its calculations of global systolic strain showed similar or better inter-oberver reproducibility than those by STE, and could be applied across RV image regions inaccessible to echo. ‘Global strain’ calculated by EBD gave similar results to FT. Measurements made using FT related to exercise tolerance in ToF patients suggesting that the approach could have clinical relevance and deserves further study.

Systemic right ventricular longitudinal strain is reduced in adults with transposition of the great arteries, relates to subpulmonary ventricular function, and predicts adverse clinical outcome

BACKGROUND Transposition of the great arteries (TGA) after atrial switch operation and congenitally corrected TGA (ccTGA) are commonly associated with impaired systemic right ventricular (RV) function and impaired prognosis. We aimed to investigate the value of indices of myocardial deformation on speckle-tracking echocardiography for quantifying ventricular function and their potential role in assessing ventricular-ventricular interaction and outcome in patients with a systemic RV. METHODS AND RESULTS A total of 129 patients (87 with TGA and atrial switch and 42 with ccTGA, 71 men, age 35 ± 12 years) were investigated, and biventricular myocardial deformation was compared with findings in healthy subjects (n = 38, age 36 ± 10 years). Systemic ventricular longitudinal 2-dimensional (2D) peak systolic strain (RV 2D-LS) was significantly reduced compared with controls (-12.9 ± 3.6 and -15.4 ± 5.1 vs -21.0 ± 5.5 in TGAs, ccTGAs, and controls, P < .0001). Systemic and pulmonary 2D-LS were correlated in patients with TGA (r = 0.46, P < .0001) and ccTGA (r = 0.64, P < .0001), suggesting interventricular interaction, and this was confirmed when ejection fraction on magnetic resonance imaging was assessed (r = 0.53, P < .0001). More importantly, systemic 2D-LS (hazard ratio 1.31, P = .01) was related to adverse clinical outcome (symptomatic progression to New York Heart Association class ≥3, clinically relevant cardiac arrhythmia, or death) in patients with TGA and atrial switch independently of ejection fraction on cardiac magnetic resonance imaging, history of clinically relevant arrhythmia, or functional class. CONCLUSIONS Global longitudinal systolic strain is significantly reduced in patients with a systemic RV, is related to subpulmonary ventricular function, and predicts adverse clinical outcome in adults with atrial switch TGA.

Changes in the Pacemaker Rate After Transition From Edwards SAPIEN XT to SAPIEN 3 Transcatheter Aortic Valve Implantation: The Critical Role of Valve Implantation Height.

OBJECTIVES The aim of this study was to analyze the pacemaker implantation rate (PMIR) with the new balloon-expandable Edwards SAPIEN 3 valve (S3) and the factors associated with it. BACKGROUND The introduction of the S3 for transcatheter aortic valve replacement (TAVR) has led to a reduction in paravalvular regurgitation. There are, however, concerns that the new design may increase the PMIR. METHODS The first 206 patients treated with the S3 were compared with 371 preceding patients treated with SAPIEN XT valves. Patients who previously underwent pacemaker or implantable cardioverter defibrillator implantation or transapical and valve-in-valve procedures were excluded from the analysis. All patients were monitored for at least 7 days. Previous and new conduction abnormalities were documented, and prosthesis implantation height was assessed for the S3. RESULTS There were no significant differences in baseline characteristics between groups. The PMIR was, however, significantly higher for the S3 (19.1% vs. 12.2%; p = 0.046). The mean implantation height was significantly lower in patients requiring PMI (67%/33% vs. 72%/28% aortic/ventricular stent extension, p = 0.032). On multivariate regression analysis, implantation height was the only independent predictor of PMI (odds ratio: 0.94 [95% confidence interval: 0.90 to 0.99]; p = 0.009). It increased from 68%/32% to 75%/25% when comparing the first with the second half of S3 implantations (p < 0.0001). This change was associated with a significant decrease in PMIR from 25.9% to 12.3% (p = 0.028), no longer different from the XT valve (12.2%). CONCLUSIONS The PMIR after TAVR is higher with the S3 than with the XT and is independently associated with the implantation height. This increase in the PMIR may be avoided by intending an aortic stent extension >70%.

Impact of transcatheter aortic valve implantation or surgical aortic valve replacement on right ventricular function.

Objective Transcatheter aortic valve implantation (TAVI) has become an alternative to surgical aortic valve replacement (sAVR) in selected high risk patients. While improvement in left ventricular function after TAVI has been demonstrated, little is known about the impact on right ventricular (RV) function. Since postoperative RV dysfunction is linked to adverse outcomes, the authors sought to investigate the effect of TAVI and aortic valve replacement (AVR) on RV function using speckle tracking echocardiography. Design Cross-sectional study in tertiary healthcare setting. Setting 101 patients with severe symptomatic aortic stenosis (age 81±11 yrs) who underwent TAVI and 22 patients who underwent sAVR were included. RV function was assessed using 2D longitudinal strain (RV-LS), fractional area change and tricuspid annular plain systolic excursion before and after sAVR and TAVI (median 89 days). Results Although the TAVI group had worse baseline characteristics, RV function remained unchanged in this group whereas significant deterioration of RV function was observed in patients undergoing conventional AVR: RV-LS (−25.2±6.1 vs −20.0±7.0%; p=0.009), RV-fractional area change (47.0±7.0 vs 39.8±10.7%, p=0.019) and tricuspid annular plain systolic excursion (24±5 vs 16±4 mm, p=0.0001). Conclusion While TAVI did not affect RV function it deteriorated significantly in patients undergoing sAVR. The authors speculate that this may be related to the detrimental effects of pericardiotomy and, to a lesser degree, cardiopulmonary bypass. While further studies are required to assess the clinical significance of this finding, these data suggest that patients with pre-existing RV dysfunction may benefit from TAVI and that RV function should be incorporated into future risk scores.

Myocardial deformation parameters predict outcome in patients with repaired tetralogy of Fallot

Background Parameters of myocardial deformation have been suggested to be superior to conventional measures of ventricular function and to predict outcome in repaired tetralogy of Fallot (ToF). We aimed to test the hypothesis that parameters of myocardial deformation on cardiac MRI (CMR) relate to symptoms and provide prognostic information in patients with repaired ToF. Methods and results We included 372 patients with ToF (median age 16 years; 55% male), recruited within a nationwide, prospective study. Longitudinal (LS), circumferential (CS) and radial global strain (RS) were analysed by CMR-based feature tracking (FT). A combined endpoint of death, successful resuscitation or documented ventricular tachycardia was employed. Parameters of global strain were associated with New York Heart Association (NYHA) class and symptomatic deterioration. During a median follow-up of 7.4 years, 20 events occurred. Left ventricular (LV) CS and right ventricular (RV) LS emerged as predictors of outcome, independent of QRS duration, LV/RV ejection fraction and volumes, NYHA class and peak oxygen uptake. In combination, these parameters also identified a subgroup of patients at significantly increased risk of adverse of outcomes (HR 3.3, p=0.002). Furthermore, LV LS, RS, CS and RV LS were related to the risk of death and nearly missed death (p<0.05 for all). Conclusions FT-CMR provides myocardial deformation parameters, easily derived from standard CMR studies. They relate to symptoms and clinical deterioration in patients with ToF. More importantly, they predict adverse outcome independent of established risk markers, and should be considered as a useful adjunct to established outcome predictors, especially in younger patients with ToF. Clinical trial registration number http://www.clinicaltrials.gov: NCT00266188; Results.

Longitudinal left ventricular 2D strain is superior to ejection fraction in predicting myocardial recovery and symptomatic improvement after aortic valve implantation

BACKGROUND Predicting improvement of myocardial function after transcatheter aortic valve implantation (TAVI) for aortic stenosis (AS) remains a challenge. As ejection fraction (EF) may be of limited value in detecting early myocardial dysfunction and predicting outcome, we assessed the potential of echocardiographic longitudinal function in this setting. MATERIALS AND METHODS Left ventricular (LV) function was assessed using EF, mitral annular plane systolic excursion (MAPSE), peak longitudinal 2D strain (LS) and strain rate (SR) in101consecutive patients with severe symptomatic AS (age 81 ± 11 years) undergoing TAVI. Echocardiography and assessment of clinical status including NYHA functional class were performed prior and after intervention (median 70 days). RESULTS Pre-interventional EF was 57 ± 17% and 32 patients (32%) had an EF<50% while 58 patients (57%) were found to have an impaired LS. After TAVI there was no significant change in EF. In contrast, LS, SR and MAPSE improved significantly (-14.0 ± 4.4 vs. -15.5 ± 4.0%; p=0.007, 0.68 ± 0.24 vs. 0.78 ± 0.23/s, p=0.002; and 9.1 ± 3.2 vs. 10.2 ± 3.3mm, p=0.006, respectively). Receiver Operating Curve characteristic analysis identified a pre-TAVI LS>-13.3% as the optimal cut-off value for predicting lack of LS recovery post TAVI. There was a marked improvement in NYHA FC after intervention (p=0.0002). Among the studied echocardiographic parameters LS change correlated closest with NYHA class improvement (r=0.42, p=0.0008). CONCLUSION Overall, LS appears to be more sensitive for detecting early myocardial damage in patients with AS compared to conventional echocardiographic parameters. More importantly, pre-interventional LS may identify irreversible myocardial dysfunction and LS improvement correlates with symptomatic improvement after intervention.

Aortic regurgitation severity after transcatheter aortic valve implantation is underestimated by echocardiography compared with MRI

Objective Aortic regurgitation (AR) after transcatheter aortic valve implantation (TAVI) is associated with a poor clinical outcome and its assessment therefore crucial. Quantification of AR by transthoracic echocardiography (TTE), however, remains challenging in this setting. The present study used quantitative flow measurement by cardiac MRI (CMR) with calculation of regurgitant fraction (RF) for the assessment of AR and compared the results with TTE. Methods and results We included 65 patients with a mean age of 82.2±8.1 years (38 women) who underwent successful TAVI with Edwards SAPIEN valves (52 transfemoral, 13 transapical). The postinterventional degree of AR was assessed by CMR and by TTE. There was agreement between CMR and TTE with regards to the absence of severe AR. However, TTE significantly underestimated the presence of moderate AR classifying it to be mild in 38 and moderate in only 5 patients, whereas CMR found mild AR in 23 and moderate in 16 patients. Overall, there was only fair agreement between CMR and TTE regarding the grading of AR with a weighted κ of 0.33. The rate of detection of TTE for more than mild AR was only 19%. Conclusions Using CMR for the quantification of AR in a sizeable group of TAVI patients, we demonstrate a strong tendency of TTE to underestimate AR compared with CMR. Since higher AR severity on echocardiography has been associated with worse patient outcome, the potential incremental prognostic value of CMR should be studied prospectively in this setting.

Value of Speckle-tracking Echocardiography and MRI-based Feature Tracking Analysis in Adult Patients after Fontan-type Palliation

BACKGROUND Patients are commonly affected by ventricular dysfunction and heart failure after Fontan palliation. Reliable quantification of ventricular function is of interest but hampered by complex ventricular anatomy and physiology. OBJECTIVES We aimed to assess myocardial function using a novel cardiac magnetic resonance imaging (CMR)-based feature-tracking (FT) technique and to study its clinical utility in Fontan patients. METHODS Retrospective study in consecutive patients attending our service. RESULTS We included 15 adult Fontan patients (age 27 ± 7 years) who underwent a standardized transthoracic echocardiographic investigation (TTE) with measurement of global strain using speckle tracking. Thirteen patients also underwent CMR, with assessment of myocardial deformation by FT, providing longitudinal and circumferential global strain for the single ventricle. The value of TTE-based strain measurements was limited by the fact that in 63% of patients at least one myocardial segment could not be adequately quantified due to limited acoustic windows. In contrast, CMR allowed for a complete visualization of all wall segments. Not surprisingly, there was poor agreement between the techniques but good or moderate interobserver variability for FT (coefficients of variability 6.6% and 14.3% for circumferential and longitudinal strain). Unlike ejection fraction, FT parameters correlated significantly with age at Fontan completion, New York Heart Association (NYHA) class, and peak oxygen uptake on cardiopulmonary exercise testing. CONCLUSIONS Assessment of myocardial function using CMR cine-based feature tracking is feasible in Fontan patients. Unlike echocardiographic techniques, FT is independent of inadequate acoustic windows and FT measurements relate to clinical parameters, suggesting that this approach could have clinical relevance in future.