Detection of left ventricular regional relaxation abnormalities and asynchrony in patients with hypertrophic cardiomyopathy with the use of tissue Doppler imaging

Left ventricular long-axis function in hypertrophic cardiomyopathy - Relationships between e`, early diastolic excursion and duration, and systolic excursion

Background

The peak velocity of early diastolic mitral annular motion (e`) is believed to provide sensitive detection of left ventricular (LV) diastolic dysfunction in hypertrophic cardiomyopathy (HCM), but other aspects of LV long-axis function in HCM have received less attention. Systolic mitral annular excursion (SExc) is also reduced in HCM and must be an intrinsic limitation to the extent of the subsequent motion during diastole. However, the effects of HCM on excursion during early diastole (EDExc) and atrial contraction (AExc), the duration of early diastolic motion (EDDur), and the relationships of EDExc with SExc, and of e`with EDExc and EDDur, are all unknown.

Methods

The study group was 22 subjects with HCM and there were 22 age and sex matched control subjects. SExc, EDExc, e`, AExc and EDDur were measured from pulsed wave tissue Doppler signals acquired from the septal and lateral walls. In the combined group of HCM and control subjects, multivariate analyses were performed to identify independent predictors of EDExc and e`for both LV walls.

Results

SExc, EDExc and e`were all lower, and EDDur was longer in the HCM group compared to the control group for both LV walls (p<0.05 for all). In contrast, AExc was lower for the septal wall in the HCM group (p<0.05), but not different between the groups for the lateral wall. In regression analyses of the combined group, EDExc was positively correlated with SExc, and SExc explained 57–86% of the variances in septal and lateral EDExc, e`was positively correlated with EDExc, and EDExc explained 58–68% of the variances of e`, whereas the combination of EDExc with EDDur explained 87–92% of the variances in e`. A diagnosis of HCM was not an independent predictor of EDExc when in combination with SExc, but was a minor contributor to the prediction of e`in combination with EDExc and EDDur.

Conclusion

In HCM, the decrease in LV longitudinal contraction is the major mechanism accounting for a lower EDExc, the lower e`is accounted for by contributions from the lower EDExc and prolongation of early diastolic motion, and there is no atrial compensation for the reduction of long-axis contraction.

Evaluation of Hypertrophic Cardiomyopathy: Newer Echo and MRI Approaches

PURPOSE OF REVIEW

This review discusses the basic and evolving echocardiographic and cardiac magnetic resonance (CMR) approaches in the diagnosis and management of patients with hypertrophic cardiomyopathy (HCM).

RECENT FINDINGS

Newer imaging technologies and techniques in both echocardiography and CMR have proved to add incremental value to our understanding of HCM. 3D reconstruction in echocardiography and CMR allows for more accurate morphological and volumetric assessment of the left ventricle. Echocardiographic and CMR-based left atrial assessment, including for its mechanical properties, has been shown to be correlated to outcomes and development of atrial fibrillation. Tissue characterization and scar burden quantification by late gadolinium enhancement on CMR has revolutionized our understanding of fibrotic processes in HCM and their contribution to disease severity and clinical outcomes. Cardiac imaging plays a crucial role in HCM patients. Using echocardiography and CMR as complementary modalities allows for improved diagnostics, optimization of treatment, and better prognostication.

Evaluation of hemodynamics in patients with hypertrophic cardiomyopathy by vector flow mapping: Comparison with healthy subjects

The present study investigated the role of energy loss assessed by vector flow mapping (VFM) in patients with hypertrophic cardiomyopathy (HCM). VFM analysis was performed in 42 patients with HCM and in 40 control subjects, which were matched for age, sex and left ventricular (LV) ejection fraction. The intra-LV and left atrial blood flow were obtained from the apical 3-chamber view, and the energy loss (EL) during the systolic and diastolic phases was calculated. The measurements were averaged over three cardiac cycles and indexed to body surface area. Compared with the controls, the left ventricular energy loss (LVEL)-total value was significantly decreased in patients with HCM during the diastolic phase (P1, P2 and P3; all P<0.05). A tendency for increased systolic LVEL-total values was observed in the patients with HCM compared with the controls (P>0.05). LVEL-base values were decreased in the patients with HCM during P1 and P2 (slow filling time). Compared with the controls, patients with HCM had lower LVEL-mid values during the diastolic phases (P0, P1, P2 and P3; all P<0.05). However, the LVEL-mid value of patients with HCM was higher compared with that of the controls during systolic P5 (P<0.05). LVEL-apex was decreased in patients with HCM during P0, P2 and P3. Compared with the controls, the left atrial energy loss (LAEL) of all three phases in patients with HCM were lower (each P<0.01). The diastolic LVEL values were significantly lower in patients with HCM compared with the controls; however, the systolic LVEL levels tended to be higher in HCM. The LAEL of the reservoir phase, conduit phase and atrial systolic phase were decreased in HCM compared with controls. The present study demonstrated that measurement of EL by VFM is a sensitive method of determining subclinical LV dysfunction in patients with HCM. The value of EL has been considered to be a quantitative parameter for the estimation of the efficiency of intraventricular blood flow.

Challenges for 'diastology': contributions from Japanese researchers

Diastology is a study to treat diastole of the heart. Transmitral flow and pulmonary venous flow velocities recorded by pulsed Doppler echocardiography provide more important information about left ventricular (LV) diastolic dysfunction [left atrial (LA)-LV coupling] than cardiac catheterization in clinical practice; however, these waveforms are influenced by loading conditions, particularly preload. The early diastolic mitral annular and LV wall motion indices measured by tissue Doppler echocardiography can evaluate LV relaxation abnormality and filling pressure by being relatively preload independent. In addition, the role of concomitant systolic longitudinal dysfunction is well characterized in asymptomatic patients and in patients with heart failure and preserved ejection fraction. Two-dimensional speckle tracking echocardiography is an angle-independent method, and has the potential to evaluate the contraction and relaxation abnormalities in the longitudinal, circumferential, and radial directions of the LV myocardium as well as LV torsion/untwisting and, moreover, deformation of the LA myocardium and large arterial wall. As a result, this new technique can facilitate the early detection of impaired LA-LV-arterial coupling in patients before occurrence of overt heart failure symptoms.

The role of imaging in the diagnosis and management of hypertrophic cardiomyopathy

Hypertrophic cardiomyopathy (HCM) is the most common genetic cardiomyopathy, affecting approximately 1:500 people. As the yield of genetic testing is only about 35-60%, the diagnosis of HCM is still clinical and based on the demonstration of unexplained and usually asymmetric left ventricular (LV) hypertrophy by imaging modalities. In the past, echocardiography was the sole imaging modality used for the diagnosis and management of HCM. However, in recent years other imaging modalities such as cardiac magnetic resonance have played a major role in the diagnosis, management and risk stratification of HCM, particularly when the location of left ventricular hypertrophy is atypical (apex, lateral wall) and when the echocardiographic imaging is sub-optimal. However, the most unique contribution of cardiac magnetic resonance is the quantification of myocardial fibrosis. Exercise stress echocardiography is the preferred provocative test for the assessment of LV outflow tract obstruction, which is detected only on provocation in one-third of the patients.

Role of multimodality cardiac imaging in the management of patients with hypertrophic cardiomyopathy: an expert consensus of the European Association of Cardiovascular Imaging Endorsed by the Saudi Heart Association

Taking into account the complexity and limitations of clinical assessment in hypertrophic cardiomyopathy (HCM), imaging techniques play an essential role in the evaluation of patients with this disease. Thus, in HCM patients, imaging provides solutions for most clinical needs, from diagnosis to prognosis and risk stratification, from anatomical and functional assessment to ischaemia detection, from metabolic evaluation to monitoring of treatment modalities, from staging and clinical profiles to follow-up, and from family screening and preclinical diagnosis to differential diagnosis. Accordingly, a multimodality imaging (MMI) approach (including echocardiography, cardiac magnetic resonance, cardiac computed tomography, and cardiac nuclear imaging) is encouraged in the assessment of these patients. The choice of which technique to use should be based on a broad perspective and expert knowledge of what each technique has to offer, including its specific advantages and disadvantages. Experts in different imaging techniques should collaborate and the different methods should be seen as complementary, not as competitors. Each test must be selected in an integrated and rational way in order to provide clear answers to specific clinical questions and problems, trying to avoid redundant and duplicated information, taking into account its availability, benefits, risks, and cost.

Left atrial distensibility and E/e' for estimating left ventricular filling pressure in patients with stable angina. -A comparative echocardiography and catheterization study-

BACKGROUND

Although E/e' (the ratio of early diastolic mitral inflow velocity to early diastolic mitral annular velocity) is widely used to measure left ventricular filling pressure (LVFP), its accuracy is questionable in coronary artery disease patients.

METHODS AND RESULTS

Echocardiograms and LVFP were obtained from 174 patients with stable angina (Canadian Cardiovascular Society angina grade I-II) who had received interventions for angiography-confirmed coronary stenosis. Compared with single-vessel groups, the multiple-vessel group exhibited lower mitral annular velocities, higher LVFP, and stronger correlations between E/regional e' and LVFP. Additionally, stronger correlations between E/regional e' and LVFP existed in patients with systolic dysfunction or lower variation of myocardial performance index (MPI) among anterior, inferior and lateral borders of mitral annulus. Average e' was not superior to any regional e' for assessing LVFP by the E/e' method. E/e' and left atrial (LA) ejection fraction (EF) correlated linearly with LVFP, but the correlation between LA distensibility and LVFP was logarithmical. Compared with E/e', LA distensibility and LAEF were superior for identifying high LVFP.

CONCLUSIONS

E/e' is not completely satisfactory for assessing LVFP in patients with stable angina, especially those with single-vessel disease, preserved systolic function or high MPI variation. For identifying high LVFP, LA distensibility and LAEF are better than E/e'.

Heterogeneity of apex-to-base dispersion in diastolic lengthening is related to impaired global left ventricular relaxation in patients with hypertrophic cardiomyopathy

BACKGROUND

The presence of apex-to-base disparity in diastolic left ventricle (LV) endocardial lengthening, based on an electromechanical activation sequence, has been recognized as an important determinant of LV diastolic properties. However, the behavior of LV apical and basal diastolic lengthening and its relationship to LV filling in hypertrophic cardiomyopathy (HCM) are unknown.

METHODS

We obtained basal and apical LV short-axis views in 27 patients with non-obstructive HCM and 25 healthy volunteers. The patients with HCM were subdivided into two groups; those with apical hypertrophy [APH(+)] or those without apical hypertrophy [APH(-)]. Eight equiangular points on the endo-myocardium at end diastole were placed in each view, and the movements of these points were automatically tracked using a two-dimensional echocardiographic tissue tracking system. Time-LV internal diameter curves were obtained and averaged. The time intervals from the aortic valve closure to the point of the first 40% of peak diastolic lengthening (T 40) were measured in each view. The standard deviation of the time to peak systolic circumferential shortening at the base and apex were calculated to assess the heterogeneity of LV contraction.

RESULTS

The time difference in the T 40 between the apex and base (dt-T 40) in the HCM-APH(+) and HCM-APH(-) groups was greater than that in the control group. The heterogeneities in LV apical systolic shortening in the HCM groups were greater than those in the control group. There were good linear correlations between the dt-T 40 and the LV early diastolic echo-parameters and the LV mass index.

CONCLUSIONS

Delayed apical relaxation and filling in patients with HCM is related to LV diastolic dysfunction and systolic dyssynchronous contraction.

Asynchrony of Left Ventricular Systolic Performance After the First Acute Myocardial Infarction in Patients with Narrow QRS Complexes: Doppler Tissue Imaging Study

BACKGROUND

Left ventricular (LV) electromechanical delay results in asynchronized contraction. However, it is not known if the presence of cardiac diseases without QRS prolongation may result in interventricular or intraventricular asynchrony. Doppler tissue imaging is now established for detecting regional contractile abnormalities and asynchrony in the LV.

OBJECTIVES

The aim of the study was to assess the degree of LV asynchrony after the first acute myocardial infarction (AMI) in patients with a narrow QRS complex using Doppler tissue imaging and correlate this with the site and extent of the infarction.

METHODS

Echocardiography with Doppler tissue imaging was performed within 1 week of AMI in 155 patients and compared with 50 age- and sex-matched healthy volunteers. Regional myocardial velocities were assessed at the 4 mitral annular sites, and the corresponding systolic velocity (Sm), early diastolic velocity (Em), time to peak Sm (Ts), and time to peak Em (Te) were measured. To assess LV synchronicity, SDs of Ts (Ts-SD) and Te (Te-SD) of all the 4 mitral annular sites were computed. Location and size of infarct were confirmed by echocardiographic wall-motion score index.

RESULTS

QRS complex duration was normal in all patients. Wall-motion score index was significantly higher in patients with anterior than inferior AMI (2.02 +/- 0.34 vs 1.24 +/- 0.21, P < .001). Ts-SD was significantly higher in patient than control group, and in patients with anterior than inferior AMI (38.21 +/- 2.59 vs 21.06 +/- 0.52 milliseconds and 43.18 +/- 3.77 vs 33.24 +/- 1.4 milliseconds, respectively, P < .001 for each), whereas Te-SD did not differ significantly among these groups (20.35 +/- 1.77 vs 18.17 +/- 1.14 milliseconds and 21.6 +/- 1.35 vs 19.1 +/- 1.11 milliseconds, respectively, P > .05 for each). A strong positive correlation was detected between LV systolic asynchrony (Ts-SD) and wall-motion score index (r = .77), LV mass (r = .67), LV end-systolic dimension (r = .65), and LV end-diastolic dimension (r = .5). The correlation was negative with LV ejection fraction (r = -.70) and Sm (r = -.6); the correlation was weak with Em (r = -.33) (P < .001 for all). In multivariate logistic regression analysis, infarct size was found to be the most independent predictor for systolic asynchrony (odds ratio 3.59, 95% confidence interval [1.43-9.33], P < .001).

CONCLUSION

AMI has a significant impact on regional myocardial contractility and LV systolic (but not diastolic) synchronicity early in the course even in the absence of QRS widening or bundle branch block. The degree of LV systolic asynchrony is greater with anterior than inferior AMI and mainly determined by infarct size.

Role of Left Ventricular Regional Diastolic Abnormalities for Global Diastolic Dysfunction in Patients with Hypertrophic Cardiomyopathy

BACKGROUND

The usefulness of Doppler strain rate imaging for assessment of left ventricular regional diastolic function has not been fully determined.

OBJECTIVE

We aimed to clarify the relationships between diastolic strain rates and global diastolic function and find a useful index for regional diastolic function in patients with hypertrophic cardiomyopathy (HCM).

METHODS

Strain rate curves were obtained using an apical approach at 12 different sites of the left ventricular myocardium in 25 patients with HCM and 20 control subjects, and peak early diastolic strain rate (ESR), peak late diastolic strain rate, and the time from QRS to ESR were measured. The flow propagation velocity was measured using color M-mode Doppler echocardiography as a global diastolic index.

RESULTS

Each of the spatially averaged values of ESR and ESR/peak late diastolic strain rate and the coefficients of variation of time from QRS to ESR was significantly correlated with flow propagation velocity, but the best correlation was observed in ESR. Although both ESR and peak late diastolic strain rate of each myocardial segment of patients with HCM tended to decrease as the wall thickness increased, only ESR significantly decreased even in the segments without apparent hypertrophy.

CONCLUSIONS

In patients with HCM, the reduction of ESR was more closely associated with global diastolic dysfunction than asynchrony, and ESR may be a useful and sensitive index for regional diastolic function.

Prognostic value of intra-left ventricular electromechanical asynchrony in patients with mild hypertrophic cardiomyopathy compared with power athletes

OBJECTIVES

We sought to assess the indexes of myocardial activation delay, using Doppler myocardial imaging (DMI), as potential diagnostic tools and predictors of cardiac events in patients with hypertrophic cardiomyopathy (HCM) compared with power athletes.

BACKGROUND

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

The study population comprised 70 young patients with HCM (mean (SD) age 29.4 (5.9) years) with mild septal hypertrophy (15-19 mm) and 85 age and sex matched athletes with septal thickness >12 mm, followed up for 44.4 (10.8) months. Using pulsed DMI, myocardial peak velocities, systolic time intervals, and myocardial intraventricular and interventricular systolic delays were measured in six different basal myocardial segments.

RESULTS

DMI analysis showed in HCM lower myocardial both systolic and early diastolic peak velocities of all the segments. Patients with HCM also showed significant interventricular and intraventricular delay (p<0.0001), whereas athletes showed homogeneous systolic activation of the ventricular walls. During the follow up, seven sudden deaths occurred in the HCM group, while no cardiovascular event was observed in the group of athletes. In patients with HCM, intraventricular delay on DMI was the most powerful independent predictor of sudden cardiac death (p<0.0001). An intraventricular delay >45 ms identified with high sensitivity and specificity patients with HCM at higher risk of ventricular tachycardia and cardiac events (test accuracy 90.6%).

CONCLUSIONS

DMI may be a valid supporting tool for the differential diagnosis between HCM and "athlete's heart". In patients with HCM, DMI indexes of intraventricular delay may provide additional information for selecting subgroups of patients with HCM at increased risk of ventricular arrhythmias and sudden cardiac death at follow up. Accordingly, such patients may benefit from early intensive treatment and survey. MINIABSTRACT: Doppler myocardial imaging may represent a valid supporting tool for the differential diagnosis between mild hypertrophic cardiomyopathy (HCM) and "athlete's heart". In patients with HCM, DMI indexes of intraventricular delay may provide additional information for selecting subgroups of patients with HCM at increased risk of ventricular arrhythmias and sudden cardiac death at follow up.

Detection of left ventricular regional relaxation abnormalities in patients with hypertrophic cardiomyopathy by quantitative tissue velocity imaging

To assess the left ventricular regional relaxation abnormalities in patients with hypertrophic cardiomyopathy (HCM) by quantitative tissue velocity imaging (QTVI), Doppler echocardiography and QTVI were performed in HCM (n=10) and healthy subjects (n=11) at apical long-axis, two-chamber and four-chamber views. Regional early diastolic velocity (rVe) and regional atrial contraction (rVa) were measured at each segment of ventricular middle, basal and annular levels. Mean rVe and mean rVa at three levels as well as mean rVe/rVa ratio were calculated. Our results showed that transmitral inflow peak velocities during early diastole (E) and atrial contraction (A) were also measured and E/A ratio was calculated. The rVe of all left ventricular segments in HCM were lower than those in healthy subjects (P<0.05), but compared with healthy subjects majority of rVa in HCM were not different except inferior wall and anterior wall. E between HCM and healthy subjects was different (P=0.036), while mean rVe between them was significantly different (P<0.0001). Mean rVa and mean rVe/rVa of three levels were lower in HCM than in healthy subjects (P<0.05), but there were no differences in A and E/A between them (P=0.22, P=0.101). Left ventricular regional myocardial relaxation is reduced in HCM. Transmitral inflow E and A are influenced by preload, relaxation of myocardium and atrial contraction, etc., while rVe and rVa reflect myocardial relaxation function independently. QTVI is more sensitive and more accurate than conventional Doppler imaging for characterizingregional diastolic properties in HCM.

Usefulness of a New Proposed Tissue Doppler Imaging Global Function Index in Hypertrophic Cardiomyopathy

BACKGROUND

A global function index (GFI) derived from tissue Doppler imaging (TDI) has been proposed to improve the diagnosis of hypertrophic cardiomyopathy (HCM). We aimed to evaluate the usefulness of this index in a large selected HCM population.

METHODS

GFI =[E/Ea]/Sa, was calculated at mitral annulus lateral and septal borders in 164 HCM patients and in 40 healthy volunteers. Group comparisons and correlations between GFI and other variables were performed.

RESULTS

Of the 164 patients, 69 (42%) had a peak gradient >30 mmHg in the left ventricle outflow tract (LVOT). GFI (lateral or septal) was not normally distributed. There were differences among controls, obstructive HCM, and nonobstructive HCM (P < 0.0001), but significant overlap of GFI values were observed between groups. GFI was correlated to septal thickness (r = 0.44; P < 0.0001), left atrial diameter (r = 0.52; P < 0.0001), and LVOT gradient (r = 0.58; P < 0.0001).

CONCLUSION

In a selected HCM population, GFI was limited by its asymmetrical distribution and significant overlap of values between groups. Further studies are necessary to verify the reliability of GFI in the clinical practice and its position among other tissue Doppler indices.

Physiologic compensation is supranormal in compensated aortic stenosis: does it return to normal after aortic valve replacement or is it blunted by coexistent coronary artery disease? An intramyocardial magnetic resonance imaging study

BACKGROUND

In compensated aortic stenosis (AS), cardiac performance measured at the ventricular chamber is typically supranormal, whereas measurements at the myocardium are often impaired. We investigated intramyocardial mechanics after aortic valve replacement (AVR) and the effects relative to the presence or absence of coronary artery disease (CAD+ or CAD-), respectively.

METHODS AND RESULTS

Twenty-nine patients (46 to 91 years, 10 female) with late but not decompensated AS underwent cardiovascular MRI before AVR (PRE), with follow-up at 6+/-1 (EARLY) and 13+/-2 months (LATE) to determine radiofrequency tissue-tagged left ventricle (LV) transmural circumferential strain, torsion, structure, and function. At the myocardial level, concentric LV hypertrophy regressed 18% LATE (93+/-22 versus 77+/-17 g/m2; P<0.0001), whereas at the LV chamber level, ejection fraction was supranormal PRE, 67+/-6% (ranging as high as 83%) decreasing to 59+/-6% LATE (P<0.05), representing not dysfunction but a return to more normal LV physiology. Between the CAD+ and CAD- groups, intramyocardial strain was similar PRE (19+/-10 versus 20+/-10) but different LATE, with dichotomization specifically related to the CAD state. In the CAD- patients, strain increased to 23+/-10% (+20%), whereas in CAD+ patients it fell to 16+/-11% (-26%), representing a nearly 50% decline after AVR (P<0.05). This was particularly evident at the apex, where CAD- strain LATE improved 17%, whereas for CAD+ it decreased 2.5-fold. Transmural strain and myocardial torsion followed a similar pattern, critically dependent on CAD. AVR impacted LV geometry and mitral apparatus, resulting in decreased mitral regurgitation, negating the double valve consideration.

CONCLUSIONS

In AS patients after AVR, reverse remodeling of the supranormal systolic function parallels improvement in cardiovascular MRI-derived regression of LV hypertrophy and LV intramyocardial strain. However, discordant effects are evident after AVR, driven by CAD status, suggesting that the typical AVR benefits are experienced disproportionately by those without CAD and not by those obliged to undergo concomitant coronary artery bypass grafting/AVR.

Focalized Contractile Impairment at Hypertrophied Myocardium Proven in Consideration of Wall Stress in Patients With Hypertrophic Cardiomyopathy

In hypertrophic cardiomyopathy (HCM) a hyperkinetic state is sometimes observed in spite of impaired systolic function in the hypertrophied myocardium. The aim of the present study was to determine the mechanism of this paradox. Seventeen patients with HCM and 10 normal subjects underwent cine magnetic resonance (MR) imaging to measure percent systolic wall thickening and percent fractional shortening. The ratio of systolic radial wall stress of the LV at the hypertrophied myocardium over that at the nonhypertrophied myocardium was evaluated to describe the focal advantageous condition for wall thickening. The ratio was 0.66 +/- 0.36 at the start of contraction and 0.78 +/- 0.31 at early-systole, indicating consistently smaller radial wall stress at the hypertrophied myocardium. Although the condition for contraction was favorable (a ratio less than 1.00), percent systolic wall thickening at the hypertrophied myocardium (23.0 +/- 11.8%) was smaller than that at the nonhypertrophied myocardium (70.5 +/- 32.3%). Smaller end-diastolic dimension (HCM group; 45.2 +/- 4.2 mm, reference group; 48.9 +/- 4.1 mm, P = 0.04) with a statistically identical value of systolic decrease in intraventricular dimension (HCM group; 19.7 +/- 3.9 mm, reference group; 18.9 +/- 3.2 mm, P = 0.60) yielded high percent fractional shortening in patients with HCM (43.5 +/- 7.6%). Although contractile impairment was proven at the hypertrophied region with low radial wall stress in the HCM group, the smaller end-diastolic dimension in this group resulted in high percent fractional shortening.

Regional diastolic dysfunction in individuals with left ventricular hypertrophy measured by tagged magnetic resonance imaging--the Multi-Ethnic Study of Atherosclerosis (MESA)

BACKGROUND

Impairment of global diastolic function is considered to be the mechanism of congestive heart failure in individuals with preserved systolic left ventricular (LV) function. Left ventricular hypertrophy (LVH) is known to be a risk factor for congestive heart failure with preserved systolic function, and this process may begin as a regional process. We investigated whether regional LV diastolic function measured by magnetic resonance tagging is altered in asymptomatic participants of the MESA with LVH and preserved systolic LV function.

METHODS

Regional systolic and diastolic strain rates were calculated from strain data in 218 participants of the MESA study. Circumferential strain was calculated from the midwall layer of the septum, anterior, lateral, and inferior walls at mid-LV level. Global LV function measures were studied by magnetic resonance imaging in 4291 MESA participants. Left ventricular hypertrophy for men and women was defined from the MESA population using previously established Framingham criteria.

RESULTS

Global systolic function was slightly less in the LVH (ejection fraction = 0.66 +/- 0.10) versus the non-LVH group (ejection fraction = 0.69 +/- 0.07, P < .001). Stepwise regression analyses showed a direct relationship between regional diastolic dysfunction and increasing LV mass. Regional systolic strain and strain rate measures from participants with LVH were not significantly different from those without LVH. However, regional diastolic strain rate was significantly reduced in participants with LVH (1.5 +/- 1.1 s(-1)) compared with the non-LVH group (2.2 +/- 1.1 s(-1), P < .001) regardless of age or sex.

CONCLUSIONS

Left ventricular hypertrophy is associated with regional diastolic dysfunction in individuals without evidence of clinical cardiovascular disease and preserved systolic function. Magnetic resonance imaging tagging provides detailed quantification of regional diastolic function noninvasively.

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.

Quantitative assessment of regional peak myocardial acceleration during isovolumic contraction and relaxation times by tissue Doppler imaging

OBJECTIVE

To examine regional wall acceleration and its relation to relaxation.

STUDY DESIGN

8 sheep were examined by tissue Doppler ultrasound imaging (VingMed Vivid FiVe) in apical four chamber views to evaluate the left ventricular wall divided into six segments and the mitral annulus in two segments. Peak myocardial acceleration during isovolumic periods (pIVA) derived from tissue Doppler echocardiography was analysed during isovolumic contraction (ICT) and relaxation times (IRT) in each segment.

INTERVENTIONS

After scanning at baseline, haemodynamic status was changed by administration of blood, dobutamine, and metoprolol. Changes of pIVA during IRT and ICT were compared over the four haemodynamic conditions in parallel with their peak positive and negative dP/dt measured with a high frequency manometer tipped catheter.

RESULTS

pIVA of the basal lateral segment during ICT correlated most strongly with peak positive dP/dt (r = 0.96, p < 0.0001) and there was good correlation between pIVA of the mitral valve annulus in the septum during IRT and peak negative dP/dt (r = 0.80, p < 0.0001). pIVA differed significantly between the four haemodynamic conditions during ICT in all segments (p < 0.05); pIVA during IRT did not differ significantly between the four conditions.

CONCLUSIONS

pIVA of the basal lateral wall during ICT correlated most strongly with peak positive dP/dt, and pIVA of the septal mitral valve annulus during IRT correlated well with peak negative dP/dt.

Left ventricular systolic asynchrony after acute myocardial infarction in patients with narrow QRS complexes

BACKGROUND

The aim of the study was to assess the degree of left ventricular (LV) asynchrony after myocardial infarction (MI) in patients with a narrow QRS complex using tissue Doppler imaging (TDI) and correlate this with the site and extent of the infarction measured by contrast-enhanced magnetic resonance imaging (Ce-MRI).

METHODS

Echocardiography with TDI and Ce-MRI was performed within 6 days of acute MI in 47 patients and compared with 69 age-matched healthy volunteers. Regional myocardial velocities were assessed in 12 segments, and the corresponding systolic velocity (Sm), early diastolic velocity (Em), as well as the time to peak Sm (Ts) and time to peak Em (Te) were measured. To assess LV synchronicity, SDs of Ts (Ts-SD) and Te (Te-SD) of all 12 segments were computed. Location and size of infarct were confirmed by Ce-MRI with a 16-segment model.

RESULTS

All the patients had a normal QRS complex duration. The Ts-SD was significantly prolonged in the MI group when compared with controls (42.2 +/- 13.7 vs 18.0 +/- 7.0 milliseconds, P < .001). The Ts-SD was longer in patients with anterior than inferior MI (46.8 +/- 13.9 vs 34.6 +/- 8.5 milliseconds, P = .002). Stepwise multiple regression analysis revealed that infarct size was the main independent predictor of systolic asynchrony ( B = 0.79, 95% CI 0.75-1.23, P < .001). Asynchrony was not related to the transmurality of the infarction.

CONCLUSIONS

Myocardial infarction has a significant impact on LV synchronicity even in those with a narrow QRS complex. The degree of LV systolic asynchrony is mainly determined by the infarct size and not transmurality.

Tissue Doppler imaging in the evaluation of patients with cardiac amyloidosis

PURPOSE OF REVIEW

Although two-dimensional, M-mode, and Doppler echocardiography have played a major role in the assessment of amyloid deposition in the heart, diagnosis of cardiac amyloidosis (CA) based on these conventional techniques is often only possible once the disease is in a relatively advanced stage. To optimize survival, early diagnosis and institution of therapy are essential. Recently, tissue Doppler imaging (TDI) and myocardial strain rate (SR) have emerged as important clinical tools in the assessment of CA.

RECENT FINDINGS

Tissue Doppler imaging-derived modalities including TDI velocities, strain, and SR are currently being used in the early diagnosis and evaluation of patients with CA. Although these new indices have been examined in relatively few patients, findings suggest an important and expanding role of TDI in amyloid infiltration of the heart.

SUMMARY

This review summarizes the recent literature addressing the role of TDI velocities, strain, and SR in the diagnosis and assessment of CA.

Tissue Doppler imaging for the evaluation of patients with hypertrophic cardiomyopathy

PURPOSE OF REVIEW

To discuss the role of tissue Doppler imaging for assessing regional myocardial function in patients with proven or suspected hypertrophic cardiomyopathy and review its application in clinical practice for diagnosis, estimation of filling pressures, and monitoring of treatment.

RECENT FINDINGS

Patients with hypertrophic cardiomyopathy have very abnormal systolic and diastolic myocardial function, even if global systolic function of the left ventricle appears normal. Regional function is most abnormal in walls that are markedly hypertrophied, but it is also abnormal in segments that are not affected by hypertrophy, and it is depressed in patients who have a mutation for hypertrophic cardiomyopathy but have not yet developed clear phenotypic changes. Genetic diagnosis remains difficult especially in sporadic cases, due to the very large number of mutations that have been identified; the hypertrophy may represent a nonspecific compensatory response to any mutation that impairs myofibrillar function. Subclinical changes especially affect long-axis ventricular function, and tissue Doppler imaging is the most sensitive test to identify reduced velocities of long-axis shortening and early diastolic lengthening of the left ventricle, prolonged contraction and relaxation times, and reduced strain in affected segments, both in patients with hypertrophy and in asymptomatic subjects with mutations. It can also discriminate well between hypertrophic cardiomyopathy and athlete's heart, and can be used with standard echocardiographic measurements to estimate left ventricular filling pressure or to monitor treatment.

SUMMARY

Tissue Doppler imaging can now be usefully incorporated into the routine echocardiographic study of patients with proven or suspected hypertrophic cardiomyopathy.

Longitudinal myocardial velocity gradient derived from pulsed Doppler tissue imaging in AL amyloidosis: a sensitive indicator of systolic and diastolic dysfunction

OBJECTIVE

This study was performed to clarify whether the longitudinal myocardial velocity gradient could give new insights into the features of congestive heart failure in patients with primary amyloidosis.

METHODS

A total of 33 consecutive patients with biopsy specimen-proven primary amyloidosis were examined by pulsed Doppler tissue imaging.

RESULTS

In all, 22 had evidence of heart involvement, of whom 11 had clinical congestive heart failure. Sample volumes were placed on basal and midventricle in the apical 2- and 4-chamber views. Peak systolic, and peak early and late diastolic wall-motion velocities were measured at each site. Longitudinal myocardial velocity gradients were calculated as the difference between basal and midmyocardial velocities. Single-point analysis of pulsed Doppler tissue imaging could not distinguish any difference among groups, whereas the longitudinal myocardial velocity gradients in systole and early diastole were significantly impaired in the patients with congestive heart failure compared with both the patients without cardiac involvement and those with cardiac amyloidosis without congestive heart failure.

CONCLUSION

Longitudinal myocardial velocity gradient is a sensitive method for detecting systolic and diastolic dysfunction in cardiac amyloidosis and is superior to single-point analysis Doppler tissue imaging.

Assessment of regional left ventricular filling dynamics using color kinesis in patients with hypertrophic cardiomyopathy

OBJECTIVES

Using color kinesis, we evaluated regional left ventricular filling dynamics in patients with hypertrophic cardiomyopathy (HCM).

METHODS

In all, 20 patients (14 men and 6 women) and 20 age-matched healthy control subjects (10 men and 10 women) were studied. From color kinesis diastolic images in a left ventricular short-axis view, we generated regional time curves (6 segments) of left ventricular filling. The percent filling fraction at 25%, 50%, and 75% of filling time was averaged for all segments in each patient, and the SD of its mean was used as an asynchrony index at each particular filling time. The mean filling time for each segment was also measured.

RESULTS

The asynchrony index was increased significantly in mid (50%) to late (75%) diastole in patients with HCM as compared with control subjects. Patients with HCM had regional mean filling times prolonged even in the nonhypertrophic segments. Moreover, there was significant correlation between the asynchrony index at mid and late diastole, and the global mean filling time.

CONCLUSIONS

Color kinesis is useful in evaluating regional filling dynamics in patients with HCM. Our data reinforce the notion that HCM is a functionally heterogeneous disorder.

Myocardial strain rate is a superior method for evaluation of left ventricular subendocardial function compared with tissue Doppler imaging

OBJECTIVES

This study was performed to evaluate subendocardial function using strain rate imaging (SRI).

BACKGROUND

The subendocardium and mid-wall of the left ventricle (LV) play important roles in ventricular function. Previous methods used for evaluating this function are either invasive or cumbersome. Strain rate imaging by ultrasound is a newly developed echocardiographic modality based on tissue Doppler imaging (TDI) that allows quantitative assessment of regional myocardial wall motion.

METHODS

We examined eight sheep using TDI in apical four-chamber views to evaluate the LV free wall. Peak strain rates (SRs) during isovolumic relaxation (IR), isovolumic contraction (IC), and myocardial strain were measured in the endocardial (End), mid-myocardial (Mid), and epicardial (Epi) layers. For four hemodynamic conditions (created after baseline by blood, dobutamine, and metoprolol infusion), we compared differences in SR of End, Mid, and Epi layers to peak positive and negative first derivative of LV pressure (dP/dt).

RESULTS

Strain rate during IC showed a good correlation with +dP/dt (r = 0.74, p < 0.001) and during IR with -dP/dt (r = 0.67, p = 0.0003). There was a significant difference in SR between the myocardial layers during both IC and IR (End: -3.4 +/- 2.2 s(-1), Mid: -1.8 +/- 1.5 s(-1), Epi: -0.63 +/- 1.0 s(-1), p < 0.0001 during IC; End: 2.2 +/- 1.5 s(-1), Mid: 1.0 +/- 0.8 s(-1), Epi: 0.47 +/- 0.64 s(-1), p < 0.0001 during IR). Also, SRs of the End and Mid layers during IC were significantly altered by different hemodynamic conditions (End at baseline: 1.7 +/- 0.7 s(-1); blood: 2.0 +/- 1.1 s(-1); dobutamine: 3.4 +/- 2.3 s(-1); metoprolol: 1.0 +/- 0.4 s(-1); p < 0.05). Myocardial strain showed differences in each layer (End: -34.3 +/- 12.6%; Mid: -22.6 +/- 12.1%; Epi: -11.4 +/- 7.9%; p < 0.0001) and changed significantly in different hemodynamic conditions (p < 0.0001).

CONCLUSIONS

Strain and SR appear useful and sensitive for evaluating myocardial function, especially for the subendocardial region.

Myocardial velocity gradient as a noninvasively determined index of left ventricular diastolic dysfunction in patients with hypertrophic cardiomyopathy

OBJECTIVES

We investigated the utility of the peak negative myocardial velocity gradient (MVG) derived from tissue Doppler imaging (TDI) for evaluation of diastolic dysfunction in patients with hypertrophic cardiomyopathy (HCM).

BACKGROUND

Hypertrophic cardiomyopathy is characterized by impaired diastolic function with abnormal stiffness and prolonged relaxation. However, it remains difficult to evaluate these defects noninvasively.

METHODS

Both TDI and conventional echocardiography were performed in 36 patients with HCM and in 47 control subjects. Left ventricular (LV) pressure was measured simultaneously in all HCM patients and in 26 controls.

RESULTS

The peak negative MVG occurred soon after the isovolumic relaxation period during the initial phase of rapid filling (auxotonic relaxation). It was significantly smaller in HCM patients than in control subjects (2.32 +/- 0.52/s vs. 4.82 +/- 1.15/s, p < 0.0001); the cutoff value for differentiation between all HCM patients and 47 normal individuals was determined as 3.2/s. Both the left ventricular end-diastolic pressure (LVEDP) (19.6 +/- 6.1 mm Hg vs. 6.5 +/- 1.7 mm Hg, p < 0.0001) and the time constant of LV pressure decay during isovolumic diastole (tau) (44.0 +/- 6.7 ms vs. 32.1 +/- 5.5 ms, p < 0.0001) were increased in HCM patients compared with controls. The peak negative MVG was negatively correlated with both LVEDP (r = -0.75, p < 0.0001) and tau (r = -0.58, p < 0.0001).

CONCLUSIONS

A reduced peak negative MVG reflects both prolonged relaxation and elevated LVEDP. The peak negative MVG might thus provide a noninvasive index of diastolic function, yielding unique information about auxotonic relaxation in patients with HCM.

Peak mean myocardial velocities and velocity gradients measured by color M-mode tissue Doppler imaging in healthy cats

We sought to assess the feasibility of recording the myocardial velocity gradients (MVGs) and mean myocardial velocities (MMVs) measured by color M-mode tissue Doppler imaging (TDI) in the free wall of unsedated normal cats (n = 18) with a 7.4-MHz probe equipped to record TDI images. The peak MVG and MMV values during the different phases of the cardiac cycle corresponded to certain color velocity patterns occurring in the left ventricular free wall (LVFW). Biphasic shifts were recorded in the tracings of both the MVG and MMV during early diastole (E1 and E2) as well as during the isovolumic relaxation (IVR) and isovolumic contraction (IVC) phases. Stepwise regression analysis showed that age was the only significant predictor for the peak MVG values during the 2nd phase of early diastole (E2) (r = -0.79, r2 = 0.63, and P < .001). The peak late diastolic MVG values were associated positively with age (r = 0.50, r2 = 0.25, and P < .05). The peak MMV values showed a negative association with age during E2 (r = -0.71, r2 = 0.50, and P < .001) as well as during early systole (Se) (r = -0.55, r2 = 0.30, and P < .05) and late systole (SI) (r = -0.62, r2 = 0.39, and P < .01). A positive association was found between age and the peak MMV values during late diastole (r = 0.54, r2 =- 0.29, and P < .05). The MVG values showed cyclic variations consistent with wall thickness changes. The accuracy of velocity determination and the spatial resolution of the system used were validated with a phantom. To our knowledge, this study is the 1st report of the application of this technique to the myocardium of cats,providing insights into the physiology of myocardial motion. It provides reference ranges of the peak MVG and MMV values for future studies of feline myocardial diseases.

Left ventricular myocardial function in congenital valvar aortic stenosis assessed by ultrasound tissue-velocity and strain-rate techniques

A pilot study was performed to reveal the potentials of new echo Doppler techniques for the detection of myocardial changes due to congenital valvar aortic stenosis. A total of 24 patients, (age range 0.1 to 17 years), with various degrees of aortic stenosis, and 24 age- and gender-matched, healthy children were enrolled in this study. Conventional echo Doppler, tissue velocity imaging (TVI) and strain-rate imaging (StRI) measurements were carried out using the apical four-chamber view and transthoracic long-axis view. All patients had normal fractional shortening of the left ventricle (> 28%). Although the sum of septal and ventricular wall thicknesses was significantly increased in the patients (p < 0.001), only 6 of the 24 patients showed left ventricular hypertrophy. In tissue velocity mode, systolic and early diastolic wall velocity acceleration was significantly reduced in both views. Peak systolic and early diastolic wall velocities, as well as strain rate values, in the four-chamber view were significantly reduced in the patient group. The decrease was highest for the strain-rate values in all cases. In conclusion, strain rate values at different moments within the heart cycle might become important parameters in the assessment of myocardial impairment. Further studies are indicated to assess the correlation of these parameters with the severity of stenosis, left ventricular hypertrophy and irreversible myocardial function changes.

Myocardial velocity gradient reflects the severity of myocardial damage regardless of the presence or absence of mitral regurgitation

Complicating mitral regurgitation (MR) apparently enhances left ventricular ejection fraction, thereby leading to the underestimation of myocardial damage by routine echocardiography. We sought to assess the significance of myocardial velocity gradient (MVG) derived from Doppler tissue imaging as an indicator of the severity of myocardial damage in the presence or absence of MR. Peak systolic and diastolic MVG was obtained from 39 participants: 12 healthy participants, 10 patients with dilated cardiomyopathy complicating moderate to severe MR [MR (+) group], and 17 patients with dilated cardiomyopathy without significant MR [MR (-) group]. MVG was compared with standard echocardiographic and Doppler transmitral flow velocity indices. Plasma brain natriuretic peptide levels were measured in all patients. Left ventricular dimension and fractional shortening was similar between MR (+) and MR (-) groups. Plasma brain natriuretic peptide levels were significantly increased in MR (+) group (440 +/- 417 pg/mL) as compared with MR (-) group (122 +/- 107 pg/mL, P <.05). Peak systolic MVG was significantly attenuated in dilated cardiomyopathy group with or without MR [MR (+) group = 1.3 +/- 0.5 seconds(-1), MR (-) group = 2.1 +/- 0.5 seconds(-1), where normal = 4.0 +/- 0.9 seconds(-1), P <.01, respectively]. Peak systolic MVG was further attenuated in MR (+) group than in MR (-) group (P <.01). Plasma brain natriuretic peptide levels were negatively correlated with peak systolic MVG (r = -0.66, P <.0005). Peak diastolic MVG was attenuated in MR (+) and also in MR (-) groups [MR (+) group = -4.5 +/- 2.0 seconds(-1), MR (-) group = -4.4 +/- 1.1 seconds(-1), where normal = -8.7 +/- 2.4 seconds(-1), P <.01, respectively], whereas transmitral flow indices failed to distinguish MR (+) group from normal as a result of pseudonormalization. MVG may reflect the severity of myocardial damage regardless of the presence or absence of complicating MR.

Doppler tissue imaging: regional myocardial function in hypertrophic cardiomyopathy and in athlete's heart

BACKGROUND

The distinction between hypertrophic cardiomyopathy (HCM) and the athlete's (AT) heart is an important clinical problem, and the analysis of regional myocardial function with Doppler tissue imaging may be useful in the differential diagnosis.

OBJECTIVE

Our aim was to compare regional function assessed by Doppler tissue imaging in rowers and in a group of patients with HCM.

METHODS

In 24 patients with nonobstructive HCM and in 20 competitive rowers with similar age, blood pressure, and heart rate, we analyzed with pulsed Doppler tissue imaging left ventricular (LV) regional function (velocities, time intervals, heterogeneity and asynchrony indices, and meridional gradient) in the longitudinal (8 segments, apical views) and in the radial (2 segments, short-axis view) axis.

RESULTS

Compared with AT, patients with HCM showed: (1). systolic function; (a). longitudinal: lower velocities and meridional gradient; longer precontraction period (PCP); and higher PCP/LV contraction time; (b). radial: lower velocities and gradient; longer PCP; and higher PCP/LV contraction time; (2.diastolic function; (a). logitudinal: lower e (early diastolic), a (late diastolic), and e/a velocities; and longer prerelaxation time and time to peak e. The percentage of segments with e/a < 1 was 25% in the HCM group and 0% in the AT heart group; (b). radial: lower e velocity and gradient; lower e/a gradient; and longer medial prerelaxation and basal time to peak e. Most of these differences also occurred in the nonhypertrophied inferior wall of patients with HCM.

CONCLUSIONS

There are significant differences between regional LV function of competitive rowers and patients with HCM. These differences (1). occur in systole and diastole; (2). affect velocities and time intervals; (3). are more striking in the long axis, but are also seen in the short axis, and (4). also occur in nonhypertrophied segments, suggesting the usefulness of the technique in the differential diagnosis between the 2 situations, namely in individuals that fall in Maron's "grey zone."

Comparison between invasive hemodynamic measurements and noninvasive assessment of left ventricular diastolic function by use of Doppler echocardiography in healthy anesthetized cats

OBJECTIVE

To compare Doppler echocardiographic variables of left ventricular (LV) function with those obtained invasively via cardiac catheterization under a range of hemodynamic conditions.

ANIMALS

7 healthy anesthetized cats (1 to 3 years of age).

PROCEDURE

Cats were anesthetized and instrumented to measure the time constant of isovolumic relaxation (tau [tau]), LV end-diastolic pressure (LVEDP), peak negative and positive rate of change of LV pressure, arterial blood pressure, and cardiac output. Echocardiographic variables of diastolic function (isovolumic relaxation time [IVRT], early LV flow propagation velocity [Vp], transmitral and pulmonary venous flow velocity indices, and LV tissue Doppler imaging indices) were measured simultaneously over a range of hemodynamic states induced by treatments with esmolol, dobutamine, cilobradine, and volume loading. Correlation between invasive and noninvasive measures of LV filling was determined by univariate and multivariate regression analyses.

RESULTS

Significant correlations were found between tau and IVRT, peak Vp, peak late transmitral flow velocity, and peak systolic pulmonary venous flow velocity. A significant correlation was found between LVEDP and early diastolic transmitral flow velocity (peak E) and the ratio of peak E to peak Vp, but not between LVEDP and peak Vp.

CONCLUSIONS AND CLINICAL RELEVANCE

IVRT and Vp can be used as noninvasive indices of LV relaxation; Vp was independent of preload and heart rate in this study. The E:Vp ratio may be useful as an indicator of LV filling pressure.

Usefulness of pulsed tissue Doppler imaging for evaluating systolic and diastolic left ventricular function in patients with AL (primary) amyloidosis

To clarify whether pulsed tissue Doppler imaging at multiple left ventricular LV sites could help to explain the mechanism of congestive heart failure (CHF) in patients with primary amyloidosis, we examined 86 consecutive patients with primary amyloidosis confirmed by biopsy (group I, 31 patients without cardiac involvement; group II, 31 patients with evidence of heart involvement but no CHF; and group III, 24 patients with heart involvement, clinical CHF, and normal fractional shortening >28%). Peak early diastolic myocardial velocities in group II were significantly lower than those in group I, and the values in group III were also significantly lower than those in group II at most sites. In contrast to diastolic abnormalities, peak systolic wall motion velocities in group III were significantly lower than those in group II, but there were no significant differences between groups I and II. Thus, cardiac amyloidosis is characterized by an initial impairment in early cardiac relaxation, whereas CHF is associated with an impairment of peak systolic wall motion velocities, most prominently seen in the longitudinal axis. This systolic dysfunction can be detected by pulsed tissue Doppler imaging, even when ejection fraction is in the normal range.

Left ventricular diastolic function assessed using Doppler tissue imaging in patients with hypertrophic cardiomyopathy: relation to symptoms and exercise capacity

BACKGROUND

Conventional Doppler indices of left ventricular diastolic function do not correlate with symptoms or exercise capacity in patients with hypertrophic cardiomyopathy, because of their dependence on loading conditions. Diastolic mitral annular velocity measured using Doppler tissue imaging has been reported to be a preload independent index of left ventricular diastolic function.

OBJECTIVE

To determine the relation between diastolic annular velocities combined with conventional Doppler indices and symptoms or exercise capacity in hypertrophic cardiomyopathy.

METHODS

85 patients with hypertrophic cardiomyopathy and 60 normal controls were studied. Diastolic mitral annular velocities, transmitral left ventricular filling, and pulmonary venous velocities were measured.

RESULTS

Early diastolic velocities at lateral and septal annulus were lower in patients with hypertrophic cardiomyopathy than in controls (lateral Ea: 10 (3) v 18 (4) cm/s, p < 0.0001; septal Ea: 7 (2) v 12 (3) cm/s, p < 0.0001). Unlike conventional Doppler indices alone, transmitral early left ventricular filling velocity (E) to lateral Ea ratio correlated inversely with peak oxygen consumption (r = -0.42, p < 0.0001). Patients in New York Heart Association (NYHA) class III had a higher transmitral E to lateral Ea ratio (12.0 (4.6)) than those in NYHA class II (7.6 (3.1), p < 0.005) or class I (6.6 (2.6), p < 0.0001).

CONCLUSIONS

Early diastolic mitral annular velocities are reduced in patients with hypertrophic cardiomyopathy. Unlike conventional Doppler indices alone, the transmitral E to lateral Ea ratio correlates with NYHA functional class and exercise capacity.

Conscious sedation with midazolam or propofol does not alter left ventricular diastolic performance in patients with preexisting diastolic dysfunction: a transmitral and tissue Doppler transthoracic echocardiography study

The effects of midazolam and propofol on left ventricular (LV) diastolic function have not been evaluated in humans. We tested the hypothesis that midazolam and propofol alter LV diastolic function evaluated with transmitral and tissue Doppler transthoracic echocardiography in patients with normal LV systolic function in the presence and absence of preexisting diastolic dysfunction. After IRB approval and informed consent, patients (n = 34) with normal or reversed transmitral blood flow velocity E-to-A ratios received 3 escalating doses of midazolam (0.025, 0.05, and 0.1 mg/kg) or propofol (0.25, 0.5, and 1.0 mg/kg) over 10 s at 5-min intervals. Hemodynamic variables and indices of diastolic function were recorded 3 min after each dose of midazolam and propofol. Patients with diastolic dysfunction demonstrated decreased ratios of peak transmitral E-to-A wave velocity and their corresponding time-velocity integrals as compared with normal patients. Reductions in anterior and posterior mitral annulus E/A ratios were also present. Midazolam and propofol did not further alter indices of LV diastolic function in patients with impaired early LV filling. The results indicate that sedation with midazolam or propofol does not affect indices of LV diastolic performance in healthy patients and those with preexisting diastolic dysfunction.

IMPLICATIONS

Sedation with midazolam or propofol does not alter indices of left ventricular diastolic function in healthy patients and those with preexisting left ventricular filling abnormalities as evaluated by transthoracic echocardiography.

The echo-Doppler evaluation of left ventricular diastolic function. A current perspective

The role of left ventricular (LV) diastolic function in health and disease is still incompletely understood and under appreciated by most primary care physicians and many cardiologists. Physical examination, electrocardiogram, and chest radiographs are unreliable in making the diagnosis of LV diastolic dysfunction in most individuals, and invasive measurements of cardiac pressures, rates of LV relaxation, and LV compliance are costly, clinically impracticable as they carry increased risk, and require special catheters and software analysis programs. The authors address the definition of LV diastolic dysfunction, history of diastole, LV filling patterns, pulmonary venous flow velocity variables, additional ancillary data, practical echo-Doppler evaluation of LV diastolic function, and limitations.