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Background Strain rate imaging (SRI) is proposed for assessing atrial function. There are limited studies on the role of SRI in assessing the left atrial (LA) function in patients with mitral stenosis (MS). We decided to assess LA early diastolic strain to evaluate LA conduit function in two groups of patients with MS. Methods A total of 49 patients with moderate to severe MS, scheduled for percutaneous transluminal mitral commissurotomy, were categorized into two groups: normal sinus rhythm (NSR, n=24) and persistent atrial fibrillation (AF, n=25). Early diastolic strain was measured via SRI in four mid-left atrial walls by transthoracic echocardiography. Results Left atrial volume was significantly higher in AF group. LA early diastolic strain was significantly reduced in AF patients in three walls: interatrial septum (−6.78±6.22% vs −11.44±6.35%, P=.016), anterior wall (−4.47±4.30% vs −12.52±10.62%, P=.002), and inferior wall (−2.87±3.23% vs −9.73±9.67%, P=.003). After adjustment for age, heart rate, LA volume, LA thrombus, and LAA emptying velocity, there was a significant correlation between the presence of AF and left atrial average early diastolic strain. This correlation was also remarkable between existence of AF and two LA walls (i.e., anterior and inferior walls of the LA). Conclusion There was reduced average early diastolic strain in the presence of AF compared to NSR in MS patients regardless of LA volume and age. In AF patients, there is not only a loss of atrial late diastolic contraction, but also there is a reduction in early diastolic shortening of LA myocardium.

Background: Assessment of left ventricular (LV) dyssynchrony has an important role in optimizing the selection of cardiac resynchronization therapy (CRT) candidates. We compared a new semiautomatic echocardiographic modality, tissue synchronization imaging (TSI) with a manual method, color-coded tissue Doppler imaging (TDI), in the assessment of LV dyssynchrony in patients with heart failure (HF). Methods: Ninety-five patients (age = 54.5 ± 17.1 years, 66.3% male) with advanced HF (NYHA functional class ≥III and ejection-fraction ≤35%) were included in the study and evaluated echocardiographically. The time to regional peak systolic velocity (Ts) in six basal and six middle segments of the LV was measured manually using velocity curves from TDI and semiautomatically using TSI and seven parameters of systolic dyssynchrony were computed. Results: Overall, a moderate-to-good association was found between Ts derived by these two modalities, whereas the mean of Ts via TSI was significantly lower than that measured by TDI in many LV segments. The agreement between these two modalities in identifying LV dyssynchrony varied from weak to moderate according to various dyssynchrony indices. In comparison to the TDI-derived dyssynchrony indices, TSI showed a high sensitivity of more than 90% using Ts delay at the basal/all LV segments and the indices for their standard deviations (SD) for identifying LV dyssynchrony, whereas the highest specificity of 80% was achieved using the septal-lateral dyssynchrony index in the prediction of LV dyssynchrony. Conclusion: With the aid of selected LV dyssynchrony indices, the TSI method may confer enough sensitivity for a speedy evaluation and initial screening of LV dyssynchrony in HF patients; however, the current technology of TSI does not seem specific enough to replace TDI in the evaluation of dyssynchrony. (Echocardiography 2012;29:7-12)

Background: Echocardiographic measurements of time-to-peak systolic velocities (Ts) are helpful for assessing the degree of cardiac asynchrony. We assessed the degree of ventricular asynchrony in structurally normal heart according to Ts by tissue Doppler imaging. Methods: We performed conventional echocardiography and tissue velocity imaging for 65 healthy adult volunteers to measure the Ts of 12 left ventricular segments in the mid and basal levels delay of Ts and standard deviation (SD) of Ts in all and basal segments. Six frequently used markers of dyssynchrony were measured and were also compared between men and women. Data are presented as median (25th and 75th percentile). Results: Septal-lateral and anteroseptal-posterior delays were 50 (20, 90) and 20 (0, 55) ms. The delay between the longest and the shortest Ts in basal and all segments were 100 (80, 120) and 110 (83, 128) ms, respectively. SD of Ts was 39 (24, 52) ms for basal and 41 (28, 51) ms for all segments. Overall, 76.9% of cases had at least one marker of dyssynchrony. Frequencies of dyssynchrony markers were almost significantly higher in women compared to men. The most frequently observed dyssynchrony marker was SD of Ts of all segments (70.8%) and the lowest was anteroseptal-posterior delay (21.5%). Conclusions: Normal population almost had dyssynchrony by previously described markers and many of these markers were more frequent in women. Conducting more studies on normal population by other tissue Doppler modalities may give better description of cardiac synchronicity. (Echocardiography 2010;27:823-830)

Background: Longitudinal myocardial tissue velocity imaging (TVI) and strain rate imaging (SRI) quantify regional myocardial function. We aimed to measure TVI and SRI indices for inferobasal aneurysmal segments by echocardiography at rest. Method: Sixteen patients with inferobasal left ventricular (LV) aneurysm, LV ejection fraction (EF) ≤50%, and 14 normal coronaries with normal echocardiography (control group) were studied. In SRI, peak systolic strain (ST), strain rate (SR), and pattern of strain curves and in TVI, peak systolic inward motion (Sm) were evaluated all at rest. Ascending curve means systolic expansion and descending means shortening. Results: LVEF was significantly lower in the patient group. Mean ST, SR, and Sm of inferobasal segment showed significant difference between patient and control groups; for ST: 1.45 ± 7.18% versus −17.64 ± 7.45%, P < 0.0001; SR: −0.25 ± 0.26 versus −1.44 ± 0.64 sec−1, P < 0.0001; and Sm: 3.85 ± 1.26 versus 5.56 ± 1.28 cm/sec, P = 0.006, respectively. All inferobasal aneurysmal segments had ascending curve while normal segments showed a descending curve. In patient group, aneurysmal segments had significantly reduced ST and SR compared to normal segments. Normal functioning segments of patients showed significant reduction of ST and SR compared to normal LV segments in control subjects. The range of SR and ST for inferobasal aneurysmal segments did not overlap with that of the normal segments (−0.60, 0.19 and −3.00, −0.80 sec−1 for SR, and −8.30, 23.30 and −35.30, −10.00% for ST, respectively). Conclusion: SRI indices were significantly reduced in inferobasal aneurysmal segment in comparison with either the same segment in normal subjects or normal functioning segments in the same patients. SR and ST may be superior to Sm in the evaluation of inferobasal aneurysmal segments. (Echocardiography 2010;27:803-808)

AIM To study tissue velocity imaging (TVI) and strain rate imaging (SRI) indices in akinetic nonviable and normal left ventricular (LV) inferobasal segment and effect of dobutamine infusion on these indices in nonviable segments. METHODS The study population consisted of two groups: 25 patients (mean age 60.75 +/- 8.69 years) with left ventricular akinetic inferobasal nonviable segment determined by dobutamine stress echocardiography (DSE) and 14 normal coronaries (mean age 56.67 +/- 11.90 years) with normal echocardiography as control group. The following TVI and SRI parameters were measured in patient and control group: ejection phase velocity (Sm [cm/sec]), peak systolic strain (ST [%]), and strain rate (SR [per second])). RESULTS Ejection fraction was significantly lower in patient group (29.40%+/- 5.46% vs. 55.00%+/- 3.39%; P < 0.001). Several differences were observed in patients with nonviable inferobasal segments compared to control group: Sm was reduced (3.58 +/- 1.08 cm/sec vs. 5.56 +/- 1.28 cm/sec; P < 0.001); SR and ST were significantly decreased (-0.39 +/- 0.20/second vs. -1.44 +/- 0.64/second, and -3.86%+/- 4.12% vs. -17.64%+/- 7.44%, respectively; P < 0.001 in both). The range of SR for nonviable segments (-0.04 to -0.77/second) did not overlap with that of the normal segments (-0.80 to -3.0/second). This range for Sm and ST overlapped with those of the normal segments. CONCLUSION All TVI and SRI parameters are reduced in akinetic nonviable inferobasal compared with normal segments. According to findings of this study, resting strain rate has a potential to discriminate nonviable inferobasal from normal segments.