Three-dimensional anatomic features of the mitral valve that predict systolic anterior motion occurring during dobutamine stress echocardiography.

BACKGROUND/AIM: Left ventricular outflow tract obstruction related to systolic anterior motion (SAM) of the mitral valve is a common complication of dobutamine stress echocardiography (DSE). However, the mechanisms underlying SAM have not been fully characterized. The objective of the present study was to use three-dimensional echocardiography to identify anatomic features of the mitral valve that predispose to SAM during DSE. METHODS: We retrospectively evaluated consecutive patients included prospectively in our database and who had undergone 3D echocardiography (including an assessment of the mitral valve) before DSE. Patients who had developed SAM during DSE (the SAM+ group) were matched 2:3 with patients who did not (the SAM- group). RESULTS: One hundred patients were included (mean age: 67 ± 10). Compared with SAM- patients (n = 60), SAM+ patients (n = 40) had a lower mitral annular area, a smaller perimeter, and a smaller diameter (p < .01 for all, except the anteroposterior diameter). The SAM+ group had also a narrower mitral-aortic angle (126 ± 12° vs. 139 ± 11° in the SAM- group; p < .01) and a higher posterior mitral leaflet length (1.4 ± .27 cm vs. 1.25 ± .29, respectively; p < .01). Furthermore, the mitral annulus was more spherical, more flexible, and more dynamic in SAM+ patients than in SAM- patients (p < .05 for all). In a multivariate analysis of anatomic variables, the mitral-aortic angle, the mitral annular area, and posterior leaflet length were independent predictors of SAM (p ≤ .01 for all). In a multivariate analysis of standard echo and hemodynamic variables, the presence of wall motion abnormalities at rest (p < .01) was an independent predictor of SAM. CONCLUSION: SAM during DSE is multifactorial. In addition to the pharmacologic effects of dobutamine on the myocardium, 3D echocardiographic features of the mitral valve (a smaller mitral annulus, a narrower mitral-aortic angle, and a longer posterior leaflet) appear to predispose to SAM.

[Is Tako-tsubo cardiomyopathy really reversible ?] / La Cardiomyopathie de Tako-tsubo est-elle réellement réversible ?

Tako-tsubo cardiomyopathy is characterized by a total reversibility of wall motion abnormalities of the left ventricle (LV) as well as normalization of LV ejection fraction after the acute phase. However, recent studies have shown that some patients present functional, metabolic, and morphologic abnormalities away from the acute phase suggesting an incomplete recovery of the disease. In this revue we discuss about this topic through several tools used in those studies (echocardiography, exercise test, MRI, nuclear imaging, biology, as well).

Usefulness of Noninvasive Myocardial Work to Predict Left Ventricular Recovery and Acute Complications after Acute Anterior Myocardial Infarction Treated by Percutaneous Coronary Intervention.

BACKGROUND: Predicting left ventricular recovery (LVR) after acute ST-elevation myocardial infarction (STEMI) is challenging and of prognostic importance. Our objective was to evaluate the usefulness of noninvasive myocardial work (MW), a new index of global and regional myocardial performance, to predict LVR and in-hospital complications after STEMI. METHODS: Ninety-three patients with anterior STEMI (mean age, 59 ± 12 years) treated by percutaneous coronary intervention (PCI) were prospectively enrolled and underwent a transthoracic Doppler echocardiography within 24-48 hours after PCI and a median of 92 days at follow-up. Myocardial work is derived from the strain-pressure relation, integrating in its calculation the noninvasive arterial pressure. Segmental LVR was defined as a normalization of wall motion abnormalities of the affected segments and global recovery as an absolute improvement of left ventricular ejection fraction (LVEF) > 5% in patients with baseline LVEF ≤ 50%. In-hospital complications were defined as a composite of death, reinfarction, heart failure, and LV apical thrombus. RESULTS: Segmental MW was impaired in infarct segments, more severely in nonrecovering versus recovering segments (P < .01). Furthermore, global constructive MW was significantly correlated with follow-up LVEF (r = 0.58) and global longitudinal strain (r = -0.67; all P < .01). Constructive MW was the best index to predict segmental (P < .01 vs MW index, MW efficiency, and wasted work) and global recovery (P < .05 vs global longitudinal strain) with an independent association (odds ratio = 1.17, 95% CI, 1.13-1.20, and odds ratio = 1.43, 95% CI, 1.18-1.68, respectively; all P < .001). Moreover, global constructive MW was more severely impaired in patients with in-hospital complications (n = 16; P < .01). CONCLUSIONS: In patients with anterior STEMI treated by PCI, constructive MW is an independent predictor of segmental and global LVR and is significantly impaired in patients with in-hospital complications.