Search

Purpose To investigate determinants of right ventricular (RV) function in competitive athletes by a combined assessment of speckle tracking (STE) and real time 3D echocardiography (RT3DE). Methods Right ventricular function of 40 top-level rowers was compared to 43 sedentary normal controls by standard Doppler echocardiography, RT3DE, and STE. RV diameters and wall thickness, tricuspid annular plane systolic excursion (TAPSE), tricuspid E/A ratio, and pulsed tissue Doppler of lateral tricuspid annulus were analyzed. RV volumes, ejection fraction (EF), and stroke volume (SV) were determined. RV global longitudinal strain (GLS) (average of 6 regions), septal strain (average of 3 septal regions, septal longitudinal strain [SLS]), and lateral strain (average of 3 lateral regions, lateral longitudinal strain [LLS]) were estimated by STE. Results The 2 groups were comparable for age, body mass index, and blood pressure, but heart rate was lower in rowers. RV diameters were larger and TAPSE, tricuspid E/A ratio, and tissue Doppler-derived s′ and e′ velocities were higher in rowers. By RT3DE, RV end-diastolic volume (EDV) and end-systolic volume were greater in rowers (both P

Postsystolic motion (PSM) is a delayed ejection motion of the myocardium occurring after the aortic valve closure, during a generally prolonged isovolumic relaxation time (IVRT). In this review we analyze the physiopathologic mechanisms underlying PSM and the contribution of tissue Doppler for its understanding. By using various techniques, this phenomenon has been described in experimental observations and related to myocardial ischemia produced by gradual or abrupt coronary occlusion. In clinical studies, it is associated with recovery of regional myocardial function. Tissue Doppler, providing a velocity map of myocardial motion, allows an easy, noninvasive detection of PSM in the clinical setting. PSM, as identified by tissue Doppler, appears a hallmark of myocardial ischemia and viability but it may occur also in nonischemic conditions as left ventricular (LV) hypertrophy and volume overload, left bundle branch block and even in normal individuals. Strain and strain rate (SR), obtainable by off-line color tissue Doppler, may be useful to identify the mechanisms underlying PSM since these measurements reflect, respectively, the intrinsic rate and the percentage of deformation of a given myocardial segment, and are relatively independent of both overall cardiac movement and tethering of the neighboring LV segments. By using SR imaging, the ratio of PSM to regional systolic longitudinal strain can be used to separate ischemic from nonischemic PSM and appears the best quantitative parameter to identify ischemia during dobutamine stress. A method to detect LV wall asynchrony and immediate benefit of cardiac resynchronization therapy has been developed combining the assessment of tissue-tracking (TT) derived delayed longitudinal contraction and of SR-derived PSM.

PURPOSE To analyze pulsed-Doppler tissue imaging (DTI) of the right ventricular (RV) tricuspid annulus and left ventricular (LV) mitral annulus in patients paced in the DDD mode at three different pacing modes as compared with healthy subjects, and to investigate possible physiologic interaction between the RV and LV in this subgroup of patients. METHODS We selected a population of 22 subjects with pacemakers (PM) for atrioventricular (AV) block and/or sick sinus syndrome and compared them to 20 healthy subjects. Standard echo Doppler and DTI parameters were measured at baseline (heart rate [HR] 70 beats/min; AV delay 125 msec) and after at least 5 minutes of constant stimulation at two different pacing modes: (1) HR 70 beats/min, AV delay 188 msec, and (2) HR 89 beats/min, AV delay 125 msec. LV stroke volume was obtained by LV outflow Doppler method. RESULTS In the PM group, RV and LV annulus exhibited significantly higher peak systolic (S(m)) and early (E(m)) diastolic wall velocities than controls. In the PM population, LV stroke volume was strongly associated to RV E(m) peak velocity (r = 0.83; P < 0.00001) and RV S(m) peak velocity (r = 0.81; P < 0.0001). These associations between LV stroke volume and RV DTI parameters remained significant even after increase of HR and AV delay in the pacing modalities. Moreover, univariate relations were found in the PM group between DTI indexes of RV tricuspid annulus and the homologous indexes of LV mitral annulus. In a multiple linear regression analysis, both RV E(m) (P < 0.001) and RV S(m) (P < 0.001) were related independently to LV stroke volume (cumulative R(2) = 0.85, P < 0.00001). CONCLUSIONS Our findings suggest the usefulness of pulsed-DTI to display physiologic ventricular interaction in patients with PM. Therefore, DTI may be taken into account as a valuable supporting tool to predict LV systolic performance and to select the most appropriate pacing mode in individual PM patients.