Description: Aims Previous studies have identified four baseline characteristics associated with a favourable response to cardiac resynchronization therapy (CRT): female, non-ischaemic aetiology of heart failure, left bundle-branch block (LBBB), and QRS duration ≥150 ms. This study evaluated the incremental value of discoordination and dyssynchrony indices over these characteristics for the prediction of the response to CRT. Methods and results The speckle-tracking strain analysis was performed in 120 CRT candidates. Patients were divided into subgroups according to the gender (male vs. female), aetiology of heart failure (ischaemic vs. non-ischaemic), QRS morphology (LBBB vs. non-LBBB), and QRS duration (≥150 vs. 〈150 ms), respectively. Discoordination was measured using the mid-ventricular radial discoordination index (RDI-M), the ratio of the average mid-ventricular thinning to thickening during ejection. Patients with one of the four favourable characteristics were more likely to exhibit other favourable characteristics and had greater amounts of average myocardial thinning during ejection and RDI-M than those without (all P 〈 0.05). In contrast, dyssynchrony indices failed to demonstrate significant differences between male and female and between ischaemic and non-ischaemic subjects. Of 39 patients who had 6-month follow-up data after CRT, left ventricular reverse remodelling was found in 22 patients (56%). Combining the favourable characteristics and RDI-M provides the best ability to predict reverse remodelling after CRT (area under the curve = 0.85, 95% confidence interval 0.73–0.98, P 〈 0.001). Conclusion Mechanical discoordination rather than mechanical dyssynchrony provides a significant incremental value over the baseline characteristics for the prediction of the response to CRT.

Description: Aims The multifactorial mechanisms of tricuspid valve (TV) insufficiency in patients with hypoplastic left heart syndrome (HLHS) include structural anomalies of TV leaflets and ventricular dilatation. We hypothesized that 2-D echocardiography underestimates the importance of TV structural abnormalities, whereas surgical assessment underestimates the importance of motion abnormalities, and compared echocardiographic assessment with surgical description. Methods and results Two independent experts retrospectively reviewed echocardiograms of all patients who had staged single-ventricular palliation and TV repair during January 1998–December 2008, and compared with case-matched controls who did not require TV repair. Primary and secondary mechanisms of TV insufficiency were categorized, and surgical findings ascertained from operation records. There were 32 patients with a median age of 5.9 months (0.3–140) and 32 matched controls. On echocardiographic review, an abnormality of at least one leaflet was noted in every patient (100%) vs. in only 14 controls 14 (44%) ( P 〈 0.001). Leaflet prolapse was described in 22 (69%), and the restriction of a leaflet in 20 (69%). Agreement between the experts was excellent ( = 0.64–0.88). On surgical inspection, annular dilatation was found in 17 (53%), and leaflet dysplasia in 14 (44%). Agreement between echocardiographic and surgical assessment was poor ( 〈 0.6). Conclusion Important structural abnormalities are common in patients with HLHS and TV insufficiency, some readily identified by 2-D echocardiography. However, there are significant discrepancies between echocardiographic and surgical findings. Echocardiographic assessment is sensitive to detect leaflet motion abnormalities, but not leaflet structural abnormalities. Both echocardiographers and surgeons should be aware of these limitations when planning surgical interventions.

Description: Background Previous intravascular ultrasound-based virtual histology (IVUS-VH) measurement variability studies have been confined to single-frame or short-segment analysis in stable patients with minimal disease. We sought to determine the magnitude of human measurement variability in acute coronary syndrome (ACS) plaques. Methods and results Prior to percutaneous coronary intervention, we performed IVUS-VH analysis in troponin-positive ACS culprit lesions. A total of 3840 IVUS-VH frames were analysed by two operators to determine intra- and inter-observer variability. The plaque constituent area and volumes were compared using intra-class correlation coefficient (ICC); within-subjects standard deviation (WSSD, mm 2 or mm 3 ) and the repeatability coefficient (RCO) to quantify the magnitude of operator error that 95% of future measurements should not exceed. The majority of intra- and inter-observer measurements had ICC of 〉0.92 confirming excellent agreement. Only the fibrous area (0.86), fibro-fatty (FF) area (0.72) and FF volume (0.87) had ICC levels suggesting an operator error 〉10%. However, the mean RCO and the percentage this represents in single-frame analysis (area error) varied across the plaque subtypes: fibrous area = 1.64 mm 2 (59%); FF area = 0.49 mm 2 (140%); necrotic core (NC) area = 0.39 mm 2 (21.3%); dense calcium (DC) area = 0.29 mm 2 (33.7%). For full lesion pullbacks (volume error): fibrous volume = 8.14 mm 3 (9.9%); FF volume = 5.63 mm 3 (53.8%); NC volume = 3.78 mm 3 (6.9%) and DC = 2.4 mm 3 (9.6%) Conclusion As in previous studies, intra- and inter-observer ICC suggests good agreement between observers. However, this can still represent large measurement error values and percentages. These findings could impact on the interpretation of previous studies and influence future studies using IVUS-VH measurements as endpoints.

Description: Aims Asynchronous myocardial contraction adversely influences left ventricular (LV) function and is therefore associated with a poor prognosis in heart failure. Exercise-induced change in ventricular dyssynchrony may be an important determinant of dynamic changes in cardiac output and mitral regurgitation. Methods and results A prospective, longitudinal study was designed with pre-defined dyssynchrony index and outcome variables to test the hypothesis that dynamic dyssynchrony is associated with worse long-term event-free survival in patients with dilated cardiomyopathy (DCM) and ‘narrow’ QRS complex. One-hundred eighty patients (62 ± 8 years; 110 males) with NYHA class II–III, idiopathic DCM, ejection fraction ≤35%, and QRS duration 〈120 ms were selected. All the patients underwent standard Doppler echo, colour tissue velocity imaging (DTI), and supine bicycle exercise stress echocardiography. Cardiac synchronicity was defined, at rest and at peak exercise, as DTI velocity opposing-wall delay (significant if ≥65 ms). Outcome was defined as freedom from death, heart transplantation, or LV-assist device implantation, over a median follow-up of 48 months, and a Cox proportional hazards model was used for survival analysis. At baseline examination, DCM patients showed a reduced LV ejection fraction (31 + 4%). A significant electromechanical delay in 58 patients (32%). At the peak of physical exercise, a significant electromechanical delay was detected in 103 patients (57%). There were 41 events during the follow-up (23%): 28 cardiac deaths, 8 heart transplantations, and 5 LV-assist device implantations over 4 years. When adjusted for confounding baseline variables, LV end-diastolic volume, restrictive mitral flow pattern, severity of mitral regurgitation, and the presence of exercise-induced intraventricular dyssynchrony were the only independent determinants of an adverse outcome. Conclusion In patients with idiopathic DCM and narrow QRS, the increase in echocardiographic dyssynchrony during exercise was the strongest predictor of less favourable event-free survival.

Description: Aims The aim of this study was to assess the changes in the left atrial (LA) shape and to identify the determinants of these changes in chronic mitral regurgitation (MR). Methods and results We enrolled 125 consecutive patients (56 ± 16 years, 51% men) with chronic MR caused by myxomatous mitral valve disease in sinus rhythm and 45 control patients (54 ± 15 years, 55% men) undergoing transthoracic Doppler echocardiography. The LA eccentricity index (LAEi) and the LA volume index (LAVi) were used to estimate the LA shape and size, respectively. There were significant decreases in LAEi ( r = –0.723, P 〈 0.001) and increases in LAVi ( r = 0.642, P 〈 0.001) with increasing severity of MR. In multivariate stepwise linear regression analysis, regurgitant fraction (RF) was an independent determinant of the LAE, whereas RF, left ventricular (LV) mass index and LV diastolic dysfunction grade were independent determinants of the LA volume. The LAEi was positively related to the velocity of A ' in the entire population ( r = 0.238, P = 0.002). On the receiver operating characteristic (ROC) curve analysis, LAEi ≤1.30 was the best cut-off value to reflect the LA systolic dysfunction ( A ' velocity 〈7 cm/s; area under the curve was 0.78, P 〈 0.001). Conclusion LA becomes more spherical with increasing severity of MR, suggesting a decrease in LAE, which is mainly determined by the volume overload. LAE might be closely related to the LA systolic function in chronic MR.

Description: Aims Dobutamine stress echocardiography (DSE) is widely used to evaluate myocardial contractile reserve in patients with heart failure (HF). The aim of the study was to assess the relationship between the tissue Doppler (TD) mitral annulus systolic velocity (Sm) change during DSE, contractile reserve, and aerobic exercise capacity in HF patients. Methods and results Sixty-four HF patients (age 67 ± 9 years, 58% with an ischaemic aetiology, and a mean value of the ejection fraction 29 ± 7%) underwent high-dose DSE. The mean value of the TD mitral annulus septal–lateral Sm change was analysed at rest and at peak DSE. All patients underwent also the cardiopulmonary exercise test. With a receiver operating characteristic analysis, a value of 2.02 cm/s obtained as a stress–rest difference in a mean value of the peak systolic velocity of the mitral annulus (Sm) was the best value for diagnosing the myocardial contractile reserve [area under the curve 0.69 (95% CI 0.56–0.80), sensitivity 69% (95% CI 54–81), specificity 80% (95% CI 45–97)]. The patient population was divided into two groups: with rest–stress Sm change during DSE ≤ 2.02 cm/s and with rest–stress Sm change 〉2.02 cm/s. Patients with Sm rest–stress 〉2.02 change during DSE, compared with patients with rest–stress change ≤2.02, showed a lower incidence of severe diastolic dysfunction at rest (16 vs. 46%, P = 0.039) and lower E/Ea values (11 ± 5 vs. 15 ± 6, P = 0.005), similar ejection fraction at rest but higher ejection fraction at peak DSE (53 ± 14 vs. 41 ± 12%, P = 0.001), better myocardial contractile reserve assessed by a pressure–volume relationship (1.89 ± 2.01 vs. 0.58 ± 1.38 mmHg/mL/m 2 , P = 0.004), with a lower end-systolic volume (–46 ± 20 vs. –24 ± 19%, P 〈 0.001), a higher increase in the ejection fraction (23 ± 10 vs. 12 ± 10%, P = 0.001) during DSE, and better peak oxygen consumption (16 ± 4 vs. 13 ± 2 mL/kg/min, P = 0.01). Conclusion In patients with HF, the rest–stress variation of mitral annulus systolic velocities during DSE predicts the presence of myocardial contractile reserve and exercise tolerance.