Prevalence and prognostic impact of apical sparing contractility pattern in patients with aortic stenosis referred for transcatheter aortic valve implantation.

INTRODUCTION: Prolonged afterload increase in aortic stenosis (AS) may alter left ventricular (LV) contractility, irrespective of LV ejection fraction (LVEF). The prevalence and morbimortality associated with the apical sparing strain pattern (ASP), a typical finding of cardiac amyloidosis (CA), are not fully understood in patients with AS. We assessed the prevalence of the ASP in patients with severe AS and its clinical impact after transcatheter aortic valve implantation (TAVI). METHODS: Eighty-nine consecutive patients with severe AS and LV hypertrophy referred for TAVI were included. Baseline clinical and echocardiographic data were assessed, including the ASP in bull's eye plots (ASPB), relative apical longitudinal strain (RALS) and EF to global longitudinal strain (EF/GLS) ratio. We analysed all-cause mortality; a composite of all-cause mortality, stroke, and heart failure hospitalizations; and the rate of pacemaker implantation, after TAVI. RESULTS: Mean age was 82 ± 6 years and mean LVEF was 57 ± 10%. ASPB and RALS >1 were present in 43.8% and 24.7% of patients, respectively. Over a median follow-up of 13 months (IQR 6-32), ASPB was associated with higher rates of all-cause mortality (log-rank P=0.001) and was an independent predictor of all-cause mortality in multivariate analysis. Combination of the ASPB and GLS or EF/GLS ratio improved the risk stratification. Patients with RALS >1 were more likely to have new BBB and an indication for pacemaker implantation (P=0.048). CONCLUSION: The ASP, as assessed by the ASPB and RALS, was frequent in patients with AS regardless of the diagnosis of CA. The ASPB may refine risk stratification in patients referred for TAVI.

Prognostic power of anaerobic threshold parameters in patients with transposition of the great arteries and systemic right ventricle.

INTRODUCTION: Both transposition of the great arteries (TGA) previously submitted to a Senning/Mustard procedure and congenitally corrected TGA (cc-TGA) have the systemic circulation supported by the morphological right ventricle, thereby rendering these patients to heart failure events risk. The aim of this study was to evaluate cardiopulmonary exercise test parameters for stratifying the risk of heart failure events in TGA patients. METHODS: Retrospective evaluation of adult TGA patients with systemic circulation supported by the morphological right ventricle submitted to cardiopulmonary exercise test in a tertiary centre. Patients were followed up for at least 1 year for the primary endpoint of cardiac death or heart failure hospitalisation. Several cardiopulmonary exercise test parameters were analysed as potential predictors of the combined endpoint and their predictive power were compared (area under the curve). RESULTS: Cardiopulmonary exercise test was performed in 44 TGA patients (8 cc-TGA), with a mean age of 35.1 ± 8.4 years. The primary endpoint was reached by 10 (22.7%) patients, with a mean follow-up of 36.7 ± 26.8 months. Heart rate at anaerobic threshold had the highest area under the curve value (0.864), followed by peak oxygen consumption (pVO2) (0.838). Heart rate at anaerobic threshold ≤95 bpm and pVO2 ≤20 ml/kg/min had a sensitivity of 87.5 and 80.0% and a specificity of 82.4 and 76.5%, respectively, for the primary outcome. CONCLUSION: Heart rate at anaerobic threshold ≤95 bpm had the highest predictive power of all cardiopulmonary exercise test parameters analysed for heart failure events in TGA patients with systemic circulation supported by the morphological right ventricle.

Longitudinal strain by two-dimensional speckle tracking to assess ventricular function in adults with transposition of the great arteries: Can serial assessment be simplified?

INTRODUCTION: Transposition of the great arteries (TGA) is a rare form of congenital heart disease in which most patients reach adulthood. Right ventricular dysfunction is the most severe residual complication in long-term follow-up, both in patients treated by atrial switch and in those with congenitally corrected TGA. New echocardiographic tools such as longitudinal strain by two-dimensional (2D) speckle tracking may improve assessment of ventricular function in these patients. METHODS AND RESULTS: We performed a retrospective analysis of echocardiograms in adult patients with TGA (26 patients with dextro-TGA - 15 treated by atrial switch and six by arterial switch - and five with congenitally corrected TGA) and in a control group of 14 healthy individuals. Right ventricular strain was significantly worse (p<0.001), as was the corresponding annular plane systolic excursion (p=0.010) in atrial switch patients, in comparison to arterial switch patients, while no differences were found in left ventricular parameters. In the overall population, systemic right ventricular parameters were significantly less negative than pulmonary right ventricular parameters, and these were less negative than in controls. Left ventricular parameters were similar across groups, except for pulmonary left ventricular strain, which was worse than in controls (p=0.008) as well as pulmonary right ventricular strain. CONCLUSIONS: Assessment of ventricular function in patients with TGA by 2D speckle tracking longitudinal strain is easy and feasible and may be a useful tool for serial follow-up. Of particular note, we found that there is also some degree of ventricular dysfunction even after re-establishment of normal connections.

Bicuspid aortic valve outcomes.

BACKGROUND: Bicuspid aortic valve is the most common CHD. Its association with early valvular dysfunction, endocarditis, thoracic aorta dilatation, and aortic dissection is well established. OBJECTIVE: The aim of this study was to assess the incidence and predictors of cardiac events in adults with bicuspid aortic valve. METHODS: We carried out a retrospective analysis of cardiac outcomes in ambulatory adults with bicuspid aortic valve followed-up in a tertiary hospital centre. Outcomes were defined as follows: interventional - intervention on the aortic valve or thoracic aorta; medical - death, aortic dissection, aortic valve endocarditis, congestive heart failure, arrhythmias, or ischaemic heart disease requiring hospital admission; and a composite end point of both. Kaplan-Meier curves were generated to determine event rates, and predictors of cardiac events were determined by multivariate analysis. RESULTS: A total of 227 patients were followed-up over 13±9 years; 29% of patients developed severe aortic valve dysfunction and 12.3% reached ascending thoracic aorta dimensions above 45 mm. At least one cardiac outcome occurred in 38.8% of patients, with an incidence rate at 20 years of follow-up of 47±4%; 33% of patients were submitted to an aortic valve or thoracic aorta intervention. Survival 20 years after diagnosis was 94±2%. Independent predictors of the composite end point were baseline moderate-severe aortic valve dysfunction (hazard ratio, 3.19; 95% confidence interval, 1.35-7.54; p<0.01) and aortic valve leaflets calcification (hazard ratio, 4.72; 95% confidence interval, 1.91-11.64; p<0.005). CONCLUSIONS: In this study of bicuspid aortic valve, the long-term survival was excellent but with occurrence of frequent cardiovascular events. Baseline aortic valve calcification and dysfunction were the only independent predictors of events.

Usefulness of right ventricular and right atrial two-dimensional speckle tracking strain to predict late arrhythmic events in adult patients with repaired Tetralogy of Fallot.

OBJECTIVE: To determine whether right ventricular and/or atrial speckle tracking strain is associated with previous arrhythmic events in patients with repaired tetralogy of Fallot. METHODS AND RESULTS: We studied right ventricular and atrial strain in 100 consecutive patients with repaired tetralogy of Fallot referred for routine echocardiographic evaluation. Patients were divided into two groups, one with previous documentation of arrhythmias (n=26) and one without arrhythmias, in a median follow-up of 22 years. Patients with arrhythmias were older (p<0.001) and had surgical repair at an older age (p=0.001). They also had significantly reduced right ventricular strain (-14.7±5.5 vs. -16.9±4.0%, p=0.029) and right atrial strain (19.1±7.7% vs. 25.8±11.4%, p=0.001). Neither right ventricular nor right atrial strain were independent predictors of the presence of a history of documented arrhythmias, which was associated with age at correction and with the presence of residual defects. In a subanalysis after excluding 23 patients who had had more than one corrective surgery, right ventricular strain was an independent predictor of the presence of previous arrhythmic events (OR 1.19, 95% CI 1.02-1.38, p=0.025). Right atrial strain was also an independent predictor after adjustment (OR 0.93, 95% CI 0.87-0.99, p=0.029). The ideal cut-off for right ventricular strain was -15.3% and for right atrial strain 23.0%. CONCLUSIONS: Compared with conventional echocardiographic parameters, strain measures of the right heart are associated with the presence of arrhythmic events, and may be useful for risk stratification of patients with repaired tetralogy of Fallot, although a prospective study is required.