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.

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.