Author + information
- Published online June 4, 2018.
- Erberto Carluccio, MD∗ ( )(, )
- Paolo Biagioli, MD and
- Giuseppe Ambrosio, MD
- ↵∗Division of Cardiology and Cardiovascular Pathophysiology, University Hospital Santa Maria della Misericordia, Piazzale Menghini, 06132 Perugia, Italy
We read with great interest the paper by Asami et al. (1) regarding the association between right ventricular (RV) dysfunction and cardiovascular death after transcatheter aortic valve replacement. In their elegant study, RV function was pre-operatively assessed by measuring fractional area change, tricuspid annular plane systolic excursion (TAPSE), and systolic movement of the RV lateral wall by tissue Doppler imaging. Compared with patients with normal RV function, RV dysfunction was independently associated with a 3-fold higher risk of cardiovascular death at 1 year (1).
This finding reinforces the notion that RV function is a major determinant of outcome in various clinical settings. However, given that RV dysfunction has such a high prognostic value, one may surmise that efforts should be directed to unmask it when conventional indexes of RV function are normal.
Using guidelines-based cut-off values, Asami et al. (1) found RV dysfunction in 29.1% of their patients. It would be interesting to know if RV dysfunction could be detected in some of the remaining patients deemed to have “normal” RV function by traditional methods.
RV imaging evaluation has long been quite challenging and technically difficult, due to the complex shape of this chamber. TAPSE (by M-mode imaging) is the most routinely used method to evaluate RV function due to its ease of measurement, reproducibility, and prognostic value (2). However, TAPSE has well-recognized limitations, as it does not truly measure myocardial contraction or take into account the presence of regional differences in function. Tissue Doppler imaging measurements of RV systolic function also have limitations, as signal noise may influence the accuracy of measurements (3). Furthermore, as with any Doppler technique, abnormalities in RV geometry can affect the insonation angle, while translational myocardial motion will affect measurements (3). Finally, although RV fractional area change is recognized to precisely estimate RV global systolic function, it has limited reproducibility (3).
Recently, 2-dimensional strain imaging techniques, such as speckle-tracking echocardiography, have allowed cardiologists to investigate myocardial mechanics easily and with greater accuracy, as they are relatively angle independent (3). Speckle-tracking echocardiography has recently been also applied to RV, demonstrating the prognostic role of RV longitudinal strain in different clinical settings, including heart failure (4,5). By this approach, we recently documented in the setting of heart failure and reduced ejection fraction that 25% of patients in whom RV function was “preserved” according to TAPSE (>16 mm), actually had impaired RV free-wall longitudinal strain (≥−15.3%). This finding has major clinical implications, as we showed that RV free-wall longitudinal strain was superior to conventional echocardiographic measures of RV function (including TAPSE, RV fractional area change, and S′ velocity by tissue Doppler imaging) and could significantly prognosticate and reclassify event risk even in those patients with normal TAPSE values (5).
Therefore, in keeping with the important observations of Asami et al. (1), we also think that assessment of RV function could be enriched by analysis of longitudinal strain in the setting of aortic stenosis, to improve detection of RV dysfunction and risk stratification of patients who are candidate for transcatheter aortic valve replacement.
Please note: Prof. Ambrosio has received grants from Angelini, Behring, Menarini, and Merck outside of the submitted work. All other authors have reported that they have no relationships relevant to the contents of this paper to disclose.
- 2018 American College of Cardiology Foundation
- Asami M.,
- Stortecky S.,
- Praz F.,
- et al.
- Ghio S.,
- Guazzi M.,
- Scardovi A.B.,
- et al.
- Bosch L.,
- Lam C.S.P.,
- Gong L.,
- et al.
- Carluccio E.,
- Biagioli P.,
- Alunni G.,
- et al.