Prognostic value of intra-left ventricular electromechanical asynchrony in patients with hypertrophic cardiomyopathy.

AIMS: We sought to assess the indexes of myocardial activation delay, using Doppler myocardial imaging (DMI), as potential predictors of cardiac events in patients with hypertrophic cardiomyopathy (HCM). The distribution and magnitude of left ventricular (LV) hypertrophy are not uniform in patients with HCM, which results in heterogeneity of regional LV systolic function. METHODS AND RESULTS: The study population included 123 HCM patients (39.4+/-5.9 years) and 123 age- and sex-matched healthy subjects, followed up for 48.4+/-8.8 months. By use of pulsed DMI, the following regional parameters were evaluated in six different basal myocardial segments: myocardial peak velocities and systolic time-intervals; myocardial intraventricular (intra-V-Del) and interventricular (inter-V-Del) systolic delays. DMI analysis in HCM showed lower myocardial systolic and early-diastolic peak velocities of all the segments. As for time intervals, HCM showed significant inter- and intra-V delays (P<0.0001), whereas homogeneous systolic activation of the ventricular walls was assessed in controls. During the follow-up, 16 cardiac deaths (12 sudden deaths) were observed in HCM patients. InHCM, DMI intra-V-Del was the most powerful independent predictor of sudden cardiac death (P<0.0001). In particular, an intra-V-Del>45 ms is identified with high sensitivity and specificity in HCM patients at higher risk of ventricular tachycardia and sudden cardiac death (test accuracy: 88.8%). CONCLUSION: In HCM patients, DMI indexes of intra-V-Del may provide additional information for selecting subgroups of HCM patients at increased risk of ventricular arrhythmias and sudden cardiac death at follow-up. Accordingly, such patients may be more actively identified for early intensive treatment and survey.     

Myocardial systolic activation delay in patients with left bundle branch block and either normal or impaired left ventricular function

AIM OF THE STUDY: to evaluate determinants of myocardial activation delay of both left (LV) and right (RV) ventricle in patients with left bundle branch block (LBBB) and either normal or impaired LV ejection fraction (EF). METHODS: From an initial cohort of patients with LBBB, 42 patients with dilated cardiomyopathy (group A) and 33 with normal global LV systolic function (group B), all comparable in age and sex, underwent standard Doppler echo, pulsed Doppler myocardial imaging (DMI), and coronary angiography. Using DMI, the following regional parameters were evaluated in five different basal myocardial segments (LV anterior, inferior, septal, lateral walls-RV lateral wall): systolic (Sm), early- and late-diastolic (Em and Am) peak velocities. As index of myocardial systolic activation was calculated: precontraction time (PCTm) (from the beginning of Q-wave of ECG to the onset of Sm). Intraventricular systolic dyssynchrony was analyzed by difference of PCTm in different LV myocardial segments. Interventricular activation delay was calculated by the difference of PCTm between the most delayed LV segment and RV lateral wall. RESULTS: Patients of group A showed increased heart rate (HR), QRS duration and LV end-diastolic diameter, and reduced LV EF. By DMI, patients of group A showed reduced myocardial peak velocities and a significant intraventricular delay in activation of LV lateral wall, with increased regional PCTm (P < 0.001). In addition, patients with dilated cardiomyopathy showed a more pronounced interventricular dyssynchrony, even after adjustment for HR and QRS duration. By receiver operating characteristic (ROC) curve analysis, a cut-off value of 55 msec of interventricular delay showed 86% sensitivity and 92% specificity in identifying patients with impaired EF. In the overall population, by use of stepwise forward multivariate linear regression analyses, LV end-diastolic diameter (beta coefficient = 0.52; P < 0.001) and LV EF (beta coefficient =-0.58; P < 0.0001) were the only independent determinants of interventricular activation delay. CONCLUSIONS: Pulsed DMI is an effective noninvasive technique for assessing the severity of regional delay in activation of LV walls in patients with LBBB. The impairment of interventricular systolic sychronicity is strongly related to LV dilatation and to the degree of global systolic dysfunction. Therefore, patients with dilated cardiomyopathy suitable for cardiac resynchronization therapy may be better selected.     

Impaired Myocardial Function in Hypertrophic Cardiomyopathy

Background: Tissue Doppler imaging (TDI) parameters of peak myocardial velocities (S′, E′, and A′) has been employed to assess the regional left ventricular myocardial function. The global function index (GFI) derived from TDI has been recently employed to distinguish the different etiologies of left ventricular hypertrophy. Objective: To analyze whether the GFI or individual TDI parameters of peak myocardial velocities (S′, E′, and A′) allows detecting different degrees of regional myocardial dysfunction in the most frequent forms of hypertrophic cardiomyopathy (HCM). Methods: GFI = (E/E′)/S′ (where E is the peak transmitral flow velocity, E′ is the early diastolic myocardial velocity, and S′ is the peak systolic myocardial velocity) and TDI peak myocardial velocities was measured in the septal and lateral mitral annulus in 101 patients with HCM (mean age 47.5 ± 14 years, 58 women) and in age‐matched group of 30 healthy controls (mean age 46 ± 6 years, 16 women). Results: Forty‐five patients had nonobstructive asymmetric septal HCM, 20 patients had a subaortic gradient ≥ 30 mm Hg, 21 p. had apical HCM, and 15 p. had other forms of HCM (midventricular, symmetric, and biventricular). All patients with HCM exhibited a decrease in early diastolic (E′) and systolic (S′) myocardial velocities, both in the lateral and septal‐mitral annulus border, but more pronounced in septal‐mitral annulus. Septal GFI was higher in HCM patients than in healthy subjects (1.8 (1.1–2.5) and (0.57 (0.31–0.92), respectively, P < 0.001), but no differences were seen when different forms of HCM were compared. Conclusions: In a selected population of patients with HCM and a preserved left ventricular(LV) systolic function, GFI and individual TDI parameters of peak velocity (S′, E′, and A′) and E/E′ ratio were similar in different forms of HCM, indicating that in all patients with HCM there is regional systolic and diastolic myocardial dysfunction, regardless of the location of hypertrophy. (ECHOCARDIOGRAPHY, Volume 26, July 2009)     

Regional left ventricular myocardial contraction abnormalities and asynchrony in patients with hypertrophic cardiomyopathy evaluated by magnetic resonance spatial modulation of magnetization myocardial tagging.

Global left ventricular (LV) pump function is generally preserved in patients with hypertrophic cardiomyopathy (HCM). However, it is unknown whether regional myocardial contractility is impaired, especially in nonhypertrophied regions. The purpose of this study was to evaluate regional LV myocardial contraction in patients with HCM using magnetic resonance (MR) spatial modulation of magnetization (SPAMM) myocardial tagging. The study group comprised 20 patients with asymmetric septal hypertrophy (HCM group) and 16 age-matched normal patients (control group), and data were collected using transthoracic M-mode and 2-dimensional echocardiography, and MR SPAMM myocardial tagging. The systolic strain ratio, maximum systolic strain velocity, and time from end-diastole to maximum systolic strain (deltaT) in the anterior, ventricular septal, inferior and lateral regions for 2 LV short-axis sections at the levels of the chordae tendineae and papillary muscles were measured at 50-ms intervals by MR myocardial tagging. The end-diastolic anterior and ventricular septal wall thicknesses and LV mass index were significantly different between the HCM and control groups. The systolic strain ratio for all 4 walls, particularly the anterior and ventricular septal regions, was significantly lower in the HCM group. In the HCM group, the maximum systolic strain velocity was significantly lower and deltaT was significantly shorter for all 4 walls, particularly the anterior and ventricular septal regions. The standard deviation for the deltaT, calculated from the deltaT for the 8 regions of the 2 LV short-axis sections, was significantly greater in the HCM group. In conclusion, regional LV myocardial contraction is impaired in both hypertrophied and nonhypertrophied regions, and systolic LV wall asynchrony occurs in patients with HCM.     

Assessment of the Systolic Left Ventricular Myocardial Velocity Profile and Gradient Using Tissue Doppler Imaging in Patients with Hypertrophic Cardiomyopathy

To determine the systolic characteristics of the hypertrophied myocardium in patients with hypertrophic cardiomyopathy (HCM), we evaluated the left ventricular [left ventricle (LV)] myocardial velocity profile (MVP) and gradient obtained from tissue Doppler imaging (TDI). Transmural wall-motion velocities in the ventricular septum and LV posterior wall were recorded in 12 patients with asymmetric septal hypertrophy and 12 healthy volunteers, and their profiles and gradients were determined. The maximum systolic myocardial velocity gradient in the ventricular septum was significantly lower in the HCM group than in the control group (0.88 ± 0.35 versus 2.24 ± 0.41; P < 0.001), whereas the gradient in the LV posterior wall was only slightly lower in the HCM group than in the control group (2.69 ± 0.82 versus 3.45 ± 0.96). In the control group, the MVPs in the ventricular septum and LV posterior wall were closely linear, suggesting that the transmural velocity is uniform during systole. MVPs in the ventricular septum and LV posterior wall in the HCM group also were closely linear, whereas the distribution of velocities in the ventricular septum was fairly dispersed compared with the control group. The myocardial velocity gradient on the right ventricular side of the ventricular septum decreased or disappeared in the patients with HCM, suggesting a nonuniform distribution of velocities. In conclusion, the MVP and gradient obtained from TDI may represent new indices for evaluating regional LV contractile abnormality in patients with HCM.     

Assessment of myocardial velocities and global function of the left ventricle in asymptomatic patients with moderate-to-severe chronic aortic regurgitation: a tissue Doppler echocardiographic study

OBJECTIVE: Asymptomatic patients with chronic aortic regurgitation (AR) have an excellent prognosis in the presence of preserved systolic function. It is a challenge to recognize patients with subclinical myocardial dysfunction in AR. Conventional parameters still have many drawbacks in predicting early left ventricular (LV) dysfunction. Pulsed-wave tissue Doppler imaging (PW-TDI) is a useful noninvasive technique for evaluating global and regional LV systolic function. In this study, we aimed to assess clinical usefulness of TDI in predicting early disturbance of myocardial contractility in asymptomatic patients with significant AR and preserved left ventricular systolic function. METHODS AND THE RESULTS: Echocardiograms were obtained in 32 AR patients and 33 healthy subjects. In addition to conventional parameters, regional myocardial velocities, isovolumetric contraction time (mICT), isovolumetric relaxation time (mIRT), and ejection time (mET) of left ventricle were obtained by TDI and modified LV myocardial performance index (MPI) was calculated. In AR, peak systolic velocity (Sm) of septal and anterior mitral annulus, and mean Sm was significantly lower, and LVMPI was significantly higher compared to control group. CONCLUSION: The data obtained by TDI show that LV MPI is lengthened, and systolic myocardial velocities are shortened in patients having chronic AR with normal LV systolic function according to conventional echocardiographic parameters. This suggests that LV long-axis contraction and global LV performance are preciously and noticeably decreased in patients with moderate-to-severe chronic AR despite normal LV ejection fraction.     

Effect of obstruction on longitudinal left ventricular shortening in hypertrophic cardiomyopathy.

OBJECTIVES: We investigated the cause of the midsystolic drop (MSD) in left ventricular (LV) ejection velocities that are observed with hypertrophic cardiomyopathy (HCM) and severe obstruction. BACKGROUND: Dynamic obstruction is an important determinant of symptoms and adverse outcome. The MSD in velocity and flow occurs in patients with gradients >60 mm Hg. The nadir velocity in the LV occurs simultaneously with peak gradient. METHODS: We studied 36 patients with obstructive HCM and an MSD and compared them with 15 patients with HCM and no obstruction and with 25 age-matched normal control subjects. We measured LV ejection velocity proximal and distal to LV obstruction as well as tissue Doppler velocities and time intervals. RESULTS: The duration of contraction of both the septum and lateral wall is shorter in obstructed patients with the MSD than in nonobstructed HCM patients: septal contraction 203 +/- 68 ms vs. 271 +/- 41 ms (p < 0.001). Parallel reduction in the length of shortening was noted: 1.2 +/- 0.6 cm vs. 1.9 +/- 0.4 cm (p < 0.001). The ejection velocity nadir follows the septal and lateral peak velocities by 100 ms and 60 ms, respectively. The velocity nadir occurs as both walls rapidly decelerate to their premature termination: septal deceleration 79 +/- 35 cm/s2 vs. 48 +/- 21 cm/s2 (p < 0.001). With medical abolition of obstruction the MSD disappears and the duration and length of contraction normalizes. CONCLUSIONS: These data indicate that the MSD is caused by premature termination of LV segmental shortening and is a manifestation of systolic dysfunction.     

Impact of ventricular dyssynchrony on postexercise accommodation of systolic myocardial motion in hypertensive patients with heart failure and a normal ejection fraction: a tissue-Doppler echocardiography study

BackgroundWe hypothesized left ventricular (LV) dyssynchrony would affect postexercise accommodation of regional myocardial motion in patients with heart failure and a normal ejection fraction (HFNEF).Methods and ResultsTissue-Doppler echocardiography was studied in 100 hypertensive patients with LV ejection fraction >50%. Among them, 70 HFNEF patients were classified into the systolic dyssynchrony (Dys: >65 ms difference of electromechanical delay between septal and lateral segments) (43 patients) and nondyssynchrony (Ndys: 27 patients) groups, and the other 30 patients were as the control (Ctrl). The systolic myocardial velocities (Sm) of 6-basal LV segments at baseline and after exercise were analyzed. When compared with the Ctrl group, the baseline lower mean Sm of 6 LV segments in the Ndys group could increase to a similar postexercise level as that in the Ctrl group, whereas that in the Dys group remained lower after exercise (7.8 ± 1.3 versus Ndys: 8.6 ± 1.5 and Ctrl: 8.9 ± 1.2 cm/s, P < .05, respectively). This is mainly due to a much higher percentage increase of lateral Sm after exercise in the Ndys group (Ndys: 49 versus Dys: 29%, P < .05).ConclusionsDyssynchrony-related regional myocardial contractile abnormality after exercise in HFNEF patients suggested the detrimental impact of electromechanical uncoupling on HF symptoms.     

The influence of ambulatory blood pressure profile on global and regional functions of the left and the right ventricles in orderly treated hypertensive patients

BACKGROUND: The association between nondipping profile and adverse cardiovascular outcome is still controversial. Tissue Doppler imaging (TDI), a new and useful addition to standard echocardiographic imaging techniques, permits a quantitative assessment of both global and regional function and timing of myocardial velocities. In this study, we aimed to assess whether a reduced nocturnal fall in blood pressure (BP) in orderly treated hypertensive patients with satisfactory BP control is related to more prominent structural and functional alterations of the ventricles. METHOD AND RESULTS: Sixty-nine hypertensive patients with adequate BP control were divided into two groups with respect to ambulatory BP profiles as dippers and nondippers. In addition to conventional echocardiographic parameters, in septal and lateral segments of left ventricle and free wall of right ventricle, peak systolic velocity (Sm), early (Em), and late (Am) diastolic velocities, isovolumic contraction time (ICTm), isovolumic relaxation time (IRTm), and ejection times (ETm) were measured, and modified myocardial performance index (MPIm) was calculated. Left ventricular (LV) and atrial dimensions, ejection fraction, transmitral early to late diastolic flow ratio, LV mass index, and LV hypertrophy ratio did not differ between groups. Both regional and mean LV Sm, Em/Am, MPIm and right ventricular Sm and MPIm were similar in both groups. CONCLUSION: In treated hypertensive patients with satisfactory BP control, there was no significant difference in cardiac structural and functional abnormalities among dipper and nondipper subjects.     

Detection of preclinical left ventricular dysfunction in Fabry disease: the contribution of tissue Doppler.

INTRODUCTION: Fabry disease is a rare X-linked lysosomal storage disorder caused by a deficiency of alpha-galactosidase, which results in progressive intracellular accumulation of glycosphingolipids in various tissues. Cardiac involvement is frequent, with left ventricular (LV) hypertrophy (concentric, apical or asymmetric septal) as the most common finding. Evaluating LV systolic dysfunction with conventional echocardiography is not sufficiently sensitive to detect impaired myocardial function early in the course of the disease. Doppler myocardial imaging can quantify changes in global and regional longitudinal myocardial function with great precision. AIM: To identify parameters of cardiac dysfunction in patients with Fabry disease with no cardiac symptoms using conventional or Doppler echocardiography and tissue Doppler (including tissue tracking, strain and strain rate). METHODS: Four patients with Fabry disease (3 female; mean age 47 +/- 17 years) and 29 healthy controls (19 female and 10 male; mean age 38 +/- 14 years) were studied with conventional echocardiography and tissue Doppler imaging using a Vivid 7 scanner. The following parameters were measured: LV dimensions, ejection fraction (using Simpson's rule), systolic and diastolic velocities and tissue tracking of the mitral annulus at six sites (apical views). LV peak systolic strain and strain rate were obtained in 12 segments from apical views. RESULTS: Two patients had LV hypertrophy (one concentric and one apical). Diastolic impairment was detected in three patients by reduced flow propagation velocity of early transmitral flow (Vp) and E/Vp ratio. Mitral annulus systolic velocities were lower in Fabry disease than in the controls. Peak systolic strain and strain rate were diminished in all segments in three patients, showing impaired myocardial systolic function. The results are presented for each of the four patients. CONCLUSIONS: In patients with Fabry disease, with no cardiac symptoms and normal LV systolic function on conventional echocardiography, diastolic dysfunction was detected by Vp and E/Vp ratio regardless of LV hypertrophy. However, tissue Doppler imaging was able to detect impaired myocardial systolic function, particularly in patients with LV hypertrophy.     

Role of left ventricular dyssynchrony in predicting remodeling after ST elevation myocardial infarction

Background: Intraventricular dyssynchrony is associated with worsening systolic function, adverse remodeling, and clinical events. The aim of this study is to investigate whether intraventricular dyssynchrony assessed by tissue Doppler imaging (TDI) can predict left ventricular (LV) remodeling after first ST segment elevation myocardial infarction (STEMI) treated successfully with primary percutaneous coronary intervention (pPCI). Methods: Fifty‐two consecutive patients who presented with first acute STEMI were included in the study. All patients underwent successful pPCI. Standard echocardiography was performed within 48 hours of admission. LV dyssynchrony was assessed by color‐coded TDI. Dyssynchrony (Ts‐diff) was calculated by maximal temporal difference between time to peak systolic velocities (Ts) of six basal segments. Echocardiographic examination was repeated after 6 months to reassess LV volumes. LV remodeling was defined as >15% increase in LV end‐systolic volume index (LVESVI) after 6 months. Results: Eleven patients (23%) developed LV remodeling. Baseline dyssynchrony was found to be correlated with percent change in LVESVI and LV end‐diastolic volume index (LVEDVI) after 6 months. Ts‐diff, creatine kinase‐MB and mitral inflow E‐wave deceleration time (DT) were the independent predictors of remodeling after STEMI in multivariate logistic regression analysis. Receiver operating characteristic curve analysis showed that Ts‐diff >56 msec had 72.7% sensitivity and 83.8% specificity for predicting remodeling. Conclusions: LV dyssynchrony is a strong predictor of LV remodeling after acute myocardial infarction (AMI). It could be useful in risk stratification of patients after AMI. (Echocardiography 2012;29:165‐172)     

Tissue Doppler imaging a new prognosticator for cardiovascular diseases

Tissue Doppler imaging (TDI) is evolving as a useful echocardiographic tool for quantitative assessment of left ventricular (LV) systolic and diastolic function. Recent studies have explored the prognostic role of TDI-derived parameters in major cardiac diseases, such as heart failure, acute myocardial infarction, and hypertension. In these conditions, myocardial mitral annular or basal segmental (Sm) systolic and early diastolic (Ea or Em) velocities have been shown to predict mortality or cardiovascular events. In particular, those with reduced Sm or Em values of <3 cm/s have a very poor prognosis. In heart failure and after myocardial infarction, noninvasive assessment of LV diastolic pressure by transmitral to mitral annular early diastolic velocity ratio (E/Ea or E/Em) is a strong prognosticator, especially when E/Ea is > or =15. In addition, systolic intraventricular dyssynchrony measured by segmental analysis of myocardial velocities is another independent predictor of adverse clinical outcome in heart failure subjects, even when the QRS duration is normal. In heart failure patients who received cardiac resynchronization therapy, the presence of systolic dyssynchrony at baseline is associated with favorable LV remodeling, which in turn predicts a favorable long-term clinical outcome. Finally, TDI and derived deformation parameters improve prognostic assessment during dobutamine stress echocardiography. A high mean Sm value in the basal segments of patients with suspected coronary artery disease is associated with lower mortality rate or myocardial infarction and is superior to the wall motion score.     

Myocardial tissue velocity reduction is correlated with clinical neurologic severity in myotonic dystrophy

About 15% of patients with myotonic dystrophy (MD) die of ventricular arrhythmias, but few have documented left ventricular (LV) dysfunction and heart failure. This study prospectively evaluated a group of patients with MD without known heart failure to assess whether there is subclinical impairment of LV contractility using conventional 2-dimensional echocardiography and tissue Doppler imaging, and to correlate any abnormalities found with the degree of neurologic severity and cytosine-thymine-guanine trinucleotide repeat length. Twenty-two patients with MD without known heart failure were evaluated and compared with 22 healthy, age-matched controls. The patients with MD and control subjects did not differ with respect to LV ejection fraction (60 +/- 5% vs 60 +/- 4%, respectively, p = 0.86). However, peak systolic velocities were significantly lower in subjects with MD compared with controls in the basal lateral (6.1 +/- 2.6 vs 8.2 +/- 2.0 cm/s, p <0.005), basal septal (5.0 +/- 1.1 vs 6.3 +/- 1.1 cm/s, p <0.0003), and mitral annulus-lateral segments (7.6 +/- 1.9 vs 9.2 +/- 1.9 cm/s, p = 0.007). Mean LV velocities were also lower in subjects with MD (6.2 +/- 1.3 vs 7.5 +/- 1.1 cm/s, p <0.002). In subjects with MD, the peak systolic velocities correlated inversely with neurologic severity (r = -0.51, p = 0.014) but not with trinucleotide repeat length. In conclusion, patients with MD without known heart failure were found to have reduced myocardial tissue velocities; the degree of velocity reduction correlated with their neurologic severity.     

Tissue Doppler imaging a new prognosticator for cardiovascular diseases.

Tissue Doppler imaging (TDI) is evolving as a useful echocardiographic tool for quantitative assessment of left ventricular (LV) systolic and diastolic function. Recent studies have explored the prognostic role of TDI-derived parameters in major cardiac diseases, such as heart failure, acute myocardial infarction, and hypertension. In these conditions, myocardial mitral annular or basal segmental (Sm) systolic and early diastolic (Ea or Em) velocities have been shown to predict mortality or cardiovascular events. In particular, those with reduced Sm or Em values of <3 cm/s have a very poor prognosis. In heart failure and after myocardial infarction, noninvasive assessment of LV diastolic pressure by transmitral to mitral annular early diastolic velocity ratio (E/Ea or E/Em) is a strong prognosticator, especially when E/Ea is > or =15. In addition, systolic intraventricular dyssynchrony measured by segmental analysis of myocardial velocities is another independent predictor of adverse clinical outcome in heart failure subjects, even when the QRS duration is normal. In heart failure patients who received cardiac resynchronization therapy, the presence of systolic dyssynchrony at baseline is associated with favorable LV remodeling, which in turn predicts a favorable long-term clinical outcome. Finally, TDI and derived deformation parameters improve prognostic assessment during dobutamine stress echocardiography. A high mean Sm value in the basal segments of patients with suspected coronary artery disease is associated with lower mortality rate or myocardial infarction and is superior to the wall motion score.     

Assessment of right and left ventricular function by tissue Doppler echocardiography in patients after biventricular repair of pulmonary atresia with intact ventricular septum

BACKGROUND: Survival of patients with PAIVS has improved significantly with adoption of a selective management approach based on RV and coronary arterial anatomy. We sought to determine the right (RV) and left ventricular (LV) function of patients with pulmonary atresia and intact ventricular septum (PAIVS) long-term after biventricular repair. METHODS: The regional ventricular function of 22 patients (11 males) aged 12.8+/-5.6 years with PAIVS after biventricular repair was assessed by tissue Doppler echocardiography (TDE). The results were compared to those of 22 age-matched controls. RESULTS: When compared with controls, patients had significantly reduced myocardial tissue velocities, systolic and diastolic strain rate, and peak systolic strain in the basal, mid-, and apical segments of the RV free wall, interventricular septum and LV lateral wall (all with p<0.01). Heterogeneity of systolic and diastolic strain rate was observed in the RV free wall and interventricular septum in patients but not in controls. CONCLUSION: Impairment of RV and LV regional longitudinal myocardial function occurs in patients with PAIVS late after biventricular repair.     

Hypertrophic cardiomyopathy with mild left ventricular remodeling: echocardiographic assessment using left ventricular wall motion score

OBJECTIVES: The present study sought to investigate the echocardiographic features of hypertrophic cardiomyopathy (HCM) with mild left ventricular (LV) remodeling, particularly in relation to wall motion abnormalities. METHODS: Among the 137 consecutive patients with HCM, 13 patients (mean age 52 +/- 13 years) who progressed to mild LV systolic dysfunction (LV ejection fraction (LVEF) of 35-50%) were studied. By reviewing the echocardiograms of these patients, wall motion score index (WMSI) was scored using 16 segments model. RESULTS: HCM patients with mild LV systolic dysfunction exhibited mild LV dilatation, mild left atrial dilatation, septal hypertrophy, and LV wall motion impairment localized in the septal and apical regions (septal WMSI 1.94 +/- 0.33 vs. total WMSI 1.51 +/- 0.25 and posterior WMSI 1.02 +/- 0.07; p < 0.001). During follow-up, further deterioration of LV systolic function (LVEF< 35%) was noted in five patients, who had less severe hypertrophy at the initial echocardiograms. These patients developed progressive LV cavity enlargement and more severe and extensive wall motion abnormalities, accompanied by septal akinesis and wall thinning, although posterolateral wall motion impairment was relatively mild (posterior WMSI 1.80 +/- 0.27 vs. septal WMSI 2.95 +/- 0.11; p < 0.001). CONCLUSIONS: Septal and apical wall motions are reduced in HCM with mild LV remodeling. As LV dysfunction progresses, septal akinesis and wall thinning develop and LV cavity enlargement becomes more prominent, though posterolateral wall motion impairment is relatively mild.     

Regional myocardial systolic function during acute myocardial ischemia assessed by strain Doppler echocardiography.

OBJECTIVES: We sought to evaluate if echocardiographic strain measurements could detect acute myocardial ischemia, and to compare this new method with myocardial velocity measurements and wall motion score index. BACKGROUND: Tissue Doppler echocardiography (TDE) is a promising method for assessing regional myocardial function. However, myocardial velocities measured by tissue Doppler echocardiography (TDE) vary throughout the left ventricle (LV) because of tethering effects from adjacent tissue. Strain Doppler echocardiography (SDE) is a new tool for measuring regional myocardial deformation excluding the effect of adjacent myocardial tissue. METHODS: Seventeen patients undergoing angioplasty of the left anterior descending coronary artery (LAD) were studied. Left ventricular longitudinal wall motion was assessed by TDE and SDE from the apical four-chamber view before, during and after angioplasty from multiple myocardial segments simultaneously. RESULTS: Systolic strain values were uniformly distributed in the different nonischemic LV segments, whereas systolic velocities decreased from basis to apex. During LAD occlusion, strain measurement showed expansion in the apical septal segment in 16 of 17 patients (7.5 +/- 6.5% vs. -17.7 +/- 7.2%, p < 0.001) and reduced compression in the mid-septal segment (p < 0.05) compared with baseline. Segments not supplied by LAD remained unchanged. Tissue Doppler echocardiography showed reduced velocities in all septal segments (p < 0.05) during angioplasty even though LAD does not supply the basal septal segment. Negative systolic velocities were present in 11 of 17 patients. Wall motion score index increased during ischemia (1.3 +/- 0.4, p < 0.05). CONCLUSIONS: The new SDE approach might be a more accurate marker than TDE for detecting systolic regional myocardial dysfunction induced by LAD occlusion.     

Patients with ankylosing spondylitis have evidence of left ventricular asynchrony

Objectives: Ankylosing spondylitis (AS) is a chronic inflammatory disease that often leads to cardiovascular complications including aortic regurgitation and conduction disturbances. Left ventricular (LV) systolic asynchrony is defined as loss of the simultaneous peak contraction of corresponding cardiac segments. The aim of this study was to evaluate LV systolic asynchrony noninvasively in patients with AS by using tissue synchrony imaging (TSI). Methods: Asynchrony was evaluated in 77 AS patients (61 male, mean age 36.4 ± 10 years) and 40 controls (35 male, mean age 39.1 ± 8.2 years). All study population underwent a comprehensive echocardiographic evaluation including TSI. The time to regional peak systolic velocity (Ts) during the ejection phase in LV was measured from TSI images by the six‐basal and six‐midsegmental model, and four TSI parameters of systolic asynchrony were computed. Results: The baseline demographic and echocardiographic characteristics were similar between the patients enrolled and controls. All TSI parameters of LV asynchrony were prolonged in patients with AS compared to controls: the standard deviation (SD) of the 12 LV segments Ts (39.6 ± 19.6 vs. 24.7 ± 11.6, P < 0.001); the maximal difference in Ts between any 2 of the 12 LV segments (122.1 ± 52.9 vs. 82.2 ± 38.6, P < 0.001); the SD of the six basal LV segments (33.5 ± 20.2 vs. 23 ± 13.3, P = 0.008); and the maximal difference in Ts between any two of the six basal LV segments (84.6 ± 48.1 vs. 60.4 ± 34.6, P = 0.008). The asynchrony parameters were significantly correlated with index of myocardial performance (Tei index) and peak systolic mitral annular velocity. Conclusion: TSI showed presence of LV systolic asynchrony in patients with AS which may account for the cardiovascular complications of AS. (Echocardiography 2012;29:661‐667)     

Regional left ventricular diastolic function in hypertrophic cardiomyopathy: application of "sector analysis" to ECG forward and reverse gated radionuclide ventriculography

To estimate regional left ventricular (LV) diastolic filling patterns in hypertrophic cardiomyopathy (HCM), a computer-assisted method by applying "sector analysis" to ECG forward and reverse gated radionuclide ventriculography was developed. Fourteen patients with HCM (four with localized septal hypertrophy, seven with apical hypertrophy and three with septal and apical hypertrophy according to echocardiography) were observed at rest. After establishing serial 20 msec imaged frames, the LV region of interest was subdivided into eight sectors radiating from the geometric center. A time-activity curve was generated for each sector and was fitted by third-order harmonics of the Fourier series. From each fitted curve, the regional peak filling rate (rPFR) and the time of rPFR (rTPFR) in the forward gating method and regional atrial contribution to filling (rAC/FV) in the reverse gating method were calculated. The coefficient of variance of rTPFR was used as an index of LV diastolic asynchrony. In HCM, a prominent delay of rTPFR was observed in the hypertrophied regions. The coefficient of variance of rTPFR correlated inversely with global LVPFR (r = -0.62, p less than 0.05), indicating that diastolic asynchrony is one of the determinants of the LV early filling rate. Regional AC/FV was augmented in the hypertrophied regions, indicating the important role of atrial systolic LV filling for slowed early filling. Thus, this new method provides valuable information concerning regional diastolic LV wall mechanics in HCM.     

Assessment of Right Ventricular Diastolic Function by Tissue Doppler Imaging in Patients with Acute Right Ventricular Myocardial Infarction

Background: It is known that right ventricular systolic parameters as assessed by color tissue Doppler imaging (TDI) are abnormal in patients with inferior wall ST elevation myocardial infarction (IWMI) with right ventricular myocardial infarction (RVMI). This study was undertaken to determine right ventricular diastolic function as assessed by TDI in patients with acute RVMI. Methods: Thirty‐five patients with first IWMI were studied and compared with 20 age‐matched healthy controls, and categorized into those with (14 patients) and without (21 patients) RVMI based on standard ECG criteria. Peak systolic, peak early and late diastolic velocities (Sm, Em, and Am), Em/Am ratio along with time to Sm (ECG Q‐Sm) and time to Em (ECG Q‐Em) were acquired from the apical 4‐chamber view at the lateral side of tricuspid annulus using TDI. Results: Sm, Em, and Em/Am ratio was reduced significantly in patients with RVMI as compared with those without RVMI and healthy individuals (Sm [11.1 ± 2.9] vs. [14 ± 1.9] and [14.5 ± 2.1] cm/sec, P < 0.01; Em [9.2 ± 3.5] vs. [12.9 ± 3] and [14.0 ± 2.0] cm/sec, P < 0.01; Em/Am ratio 0.53 ± 0.2 vs. 0.78 ± 0.19 and 0.8 ± 0.3 [P < 0.0001]). Among the intervals, there was significant prolongation of Q‐Em (558 ± 14.8 vs. 507 ± 16.2 and 480 ± 20 ms [P < 0.0001]) but Q‐Sm and Am were not statistically different between the groups. Conclusion: Right ventricular TDI diastolic parameters are abnormal in patients with RVMI. The method of recording the velocities and time intervals are simple and can be used to assess right ventricular diastolic function in patients with RVMI. (Echocardiography 2010;27:539‐543)