Comparison by real-time three-dimensional echocardiography of left ventricular geometry in hypertrophic cardiomyopathy versus secondary left ventricular hypertrophy

Echocardiographic Characterization of Left Heart Morphology and Function in Highly Trained Male Judo Athletes

The long-term practice of judo can lead to various changes in the heart including increased dimensions of the left ventricle in diastole and thickening of the interventricular septum and the posterior wall of the left ventricle. This study aimed to assess left ventricular morphology and function in elite male judokas. A comparative cross-sectional study was conducted that included a total of 20 subjects, 10 judokas, and 10 healthy non-athletes aged 24 ± 2.85 years. Demographic and anthropometric data were analyzed. All subjects underwent a medical examination and a two-dimensional transthoracic echocardiogram. Different parameters of left ventricular morphology and function were measured and compared between athletes and non-athletes. Left ventricle mass and LV mass index were higher in judokas than in non-athletes (p < 0.05), as well as PW thickness (9.78 ± 0.89 mm vs. 8.95 ± 0.76 mm). A total of six (n = 6) of athletes had eccentric hypertrophy, while others had normal heart geometry. LVEDd, LVEDs, LVEDd/BSA, and LVEDs/BSA were significantly higher in judokas (p < 0.05). LVEDd in athletes ranged from 48 to 62 mm. These values, combined with normal diastolic function, ejection fraction, and shortening fraction, indicate that the judokas’ cardiac adaptation was physiological rather than pathological.

Basal Septal Hypertrophy as the Early Imaging Biomarker for Adaptive Phase of Remodeling Prior to Heart Failure

Hypertension plays a dominant role in the development of left ventricular (LV) remodeling and heart failure, in addition to being the main risk factor for coronary artery disease. In this review, we focus on the focal geometric and functional tissue aspects of the LV septal base, since basal septal hypertrophy (BSH), as the early imaging biomarker of LV remodeling due to hypertensive heart disease, is detected in cross-sectional clinic studies. In addition, the validation of BSH by animal studies using third generation microimaging and relevant clinical observations are also discussed in the report. Finally, an evaluation of both human and animal quantitative imaging studies and the importance of combined cardiac imaging methods and stress-induction in the separation of adaptive and maladaptive phases of the LV remodeling are pointed out. As a result, BSH, as the early imaging biomarker and quantitative follow-up of functional analysis in hypertension, could possibly contribute to early treatment in a timely fashion in the prevention of hypertensive disease progression to heart failure. A variety of stress stimuli in etiopathogenesis and the difficulty of diagnosing pure hemodynamic overload mediated BSH lead to an absence of the certain prevalence of this particular finding in the population.

Hemodynamic stress and microscopic remodeling

BACKGROUD

Heart responds to physiologic and pathologic conditions and sympathetic drive plays an important role. It has been documented that LV base is more dominantly affected by sympathetic drive compared to the other regions. LV base is more dominantly exposed to wall stress in the initial period of remodeling due to pressure-overload, since LV cavity is the largest at base. Basal septal hypertrophy (BSH) in cross-sectional data is associated with the early phase of hypertensive heart disease. BSH was confirmed by 3rd generation microscopic ultrasound in small animals. BSH as the closest location to increased afterload could be detected in variety of stress stimuli and result in a huge septal hypertrophy in advance cases possibly related to earlier exposure of hemodynamic stress to septal wall.

CONCLUSION

Effective geometric and functional evaluation of initial remodeling due to hemodynamic stress is important according to both human and animal data. These findings possibly contribute to early recognition of adaptive phase of hypertensive remodeling and more effective management in a timely fashion.

Evolution of ventricular hypertrophy and myocardial mechanics in physiological and pathological hypertrophy

Left ventricular hypertrophy (LVH) is an adaptive response to physiological or pathological stimuli, and distinguishing between the two has obvious clinical implications. However, asymmetric septal hypertrophy and preserved cardiac function are noted in early stages in both cases. We characterized the early anatomic and functional changes in a mouse model of physiological and pathological stress using serial echocardiography-based morphometry and tissue velocity imaging. Weight-matched CF-1 male mice were separated into Controls ( n = 10), treadmill Exercise 1 h daily for 5 days/wk ( n = 7), and transverse aortic constriction (TAC, n = 7). Hypertrophy was noted first in the left ventricle basal septum compared with other segments in Exercise (0.84 ± 0.02 vs. 0.79 ± 0.03 mm, P = 0.03) and TAC (0.86 ± 0.05 vs. 0.77 ± 0.04 mm, P = 0.02) at 4 and 3 wk, respectively. At 8 wk, eccentric LVH was noted in Exercise and concentric LVH in TAC. Septal E/E' ratio increased in TAC (32.6 ± 3.7 vs. 37 ± 6.2, P = 0.002) compared with the Controls and Exercise (32.3 ± 5.2 vs. 32.8 ± 3.8 and 31.2 ± 4.9 vs. 28.2 ± 5.0, respectively, nonsignificant for both). Septal s' decreased in TAC (21 ± 3.6 vs. 17 ± 4.2 mm/s, P = 0.04) but increased in Exercise (19.6 ± 4.1 vs. 29.2 ± 2.3 mm/s, P = 0.001) and was unchanged in Controls (20.1 ± 4.2 vs. 20.9 ± 5.1 mm/s, nonsignificant). With similar asymmetric septal hypertrophy and normal global function during the first 4-8 wk of pathological and physiological stress, there is an early marginal increase with subsequent decrease in systolic tissue velocity in pathological but early and progressive increase in physiological hypertrophy. Tissue velocities may help adjudicate between these two states when there are no overt anatomic or functional differences. NEW & NOTEWORTHY Pathological and physiological stress-induced ventricular hypertrophy have different clinical connotations but present with asymmetric septal hypertrophy and normal global function in their early stages. We observed a marginal but statistically significant decrease in systolic tissue velocity in pathological but progressive increase in velocity in physiological hypertrophy. Tissue velocity imaging could be an important tool in the management of asymmetric septal hypertrophy by adjudicating between these two etiologies when there are no overt anatomic or functional differences.

Effect of Sex and Sporting Discipline on LV Adaptation to Exercise

OBJECTIVES

This study sought to investigate the effect of different types of exercise on left ventricular (LV) geometry in a large group of female and male athletes.

BACKGROUND

Studies assessing cardiac adaptation in female and male athletes indicate that female athletes reveal smaller increases in LV wall thickness and cavity size compared with male athletes. However, data on sex-specific changes in LV geometry in athletes are scarce.

METHODS

A total of 1,083 healthy, elite, white athletes (41% female; mean age 21.8 ± 5.7 years) assessed with electrocardiogram and echocardiogram were considered. LV geometry was classified into 4 groups according to relative wall thickness (RWT) and left ventricular mass (LVM) as per European and American Society of Echocardiography guidelines: normal (normal LVM/normal RWT), concentric hypertrophy (increased LVM/increased RWT), eccentric hypertrophy (increased LVM/normal RWT), and concentric remodeling (normal LVM/increased RWT).

RESULTS

Athletes were engaged in 40 different sporting disciplines with similar participation rates with respect to the type of exercise between females and males. Females exhibited lower LVM (83 ± 17 g/m² vs. 101 ± 21 g/m²; p < 0.001) and RWT (0.35 ± 0.05 vs. 0.36 ± 0.05; p < 0.001) compared with male athletes. Females also demonstrated lower absolute LV dimensions (49 ± 4 mm vs. 54 ± 5 mm; p < 0.001) but following correction for body surface area, the indexed LV dimensions were greater in females (28.6 ± 2.7 mm/m² vs. 27.2 ± 2.7 mm/m²; p < 0.001). Most athletes showed normal LV geometry. A greater proportion of females competing in dynamic sport exhibited eccentric hypertrophy compared with males (22% vs. 14%; p < 0.001). In this subgroup only 4% of females compared with 15% of males demonstrated concentric hypertrophy/remodeling (p < 0.001).

CONCLUSIONS

Highly trained athletes generally show normal LV geometry; however, female athletes participating in dynamic sport often exhibit eccentric hypertrophy. Although concentric remodeling or hypertrophy in male athletes engaged in dynamic sport is relatively common, it is rare in female athletes and may be a marker of disease in a symptomatic athlete.

The Effect of Dobutamine Stress on Left Ventricular Outflow Tract Gradients in Hypertensive Patients with Basal Septal Hypertrophy

Basal septal hypertrophy (BSH), a cause of left ventricular outflow tract (LVOT) obstruction, is thought to occur by increased ventricular dynamics. The aim of the study was to evaluate the effect of pharmacologic stress on LVOT gradients in a group of hypertensive patients with BSH. Dobutamine stress was used in 24 hypertensive patients (mean age 56 ±8 years; 11 women) with BSH and 20 normal controls (mean age 54 ±9 years; 7 women). Ejection fraction and myocardial mass, basal septal dimension, and LVOT diameter were measured with 2-dimensional echocardiography. LVOT velocities and transmitral velocities before and at peak dobutamine infusion were determined by continuous wave Doppler and pulsed Doppler, respectively. There were no differences in mean ejection fraction and myocardial mass between BSH patients (58 ±3%, 204 ±24 g) and normals (56 ±4%, 201 ±32 g). The basal septum was thicker in patients (1.55 ±0.2 cm) than in normals (1.03 ±0.1 cm, p<0.001). Maximum LVOT velocities were similar in BSH (1.2 ±0.4 m/sec) and normals (1.1 ±0.2 m/sec) at rest. At peak stress, maximum LVOT velocities were higher in BSH (3.3 ±0.6 m/sec) than normals (1.7 ±0.4 m/sec, p<0.001). LV rate-pressure product at peak stress was higher in BSH (23,326 ±4,388) than normals (17,592 ±2,409, p<0.001). LV isovolumetric relaxation time was prolonged, and the E/A ratio was decreased in the patients at rest (130 ±14 msec and 0.72 ±0.18, respectively, p<0.001). At peak stress, diastolic function did not significantly change in two groups. The correlations between LVOT velocity change by stress and mean LVOT diameter ( r =-0.668, p<0.001) and mean BS thickness ( r =0.610; p<0.001) were significant in the whole group. High velocities appeared on LVOT at peak pharmacologic stress in the hypertensive patients with BSH compared with control group. This suggests dynamic ventricular ejection by stress may contribute to hypertrophy of the basal segment, which is the closest part of septum to increased afterload.

Could early septal involvement in the remodeling process be related to the advance hypertensive heart disease?

BACKGROUND

Quantitative imaging analyses showed an earlier septal wall involvement in hypertension. We planned to determine the effect of hypertension on regional myocardial performance index (MPI) in a hypertensive patient population.

METHODS

We evaluated 119 hypertensive patients who were divided into gr. I: 57 patients without left ventricular hypertrophy (LVH), (53.1 ± 10 years), and gr. II: 62 patients with LVH (55.1 ± 9 years) using conventional and tissue doppler imaging. They were compared with gr. III, a sex-age-matched normal control group (37 subjects, 53.0 ± 10 years).

RESULTS

We detected basal septal and basal lateral contraction time (CT), isovolumetric CT and relaxation time (IVRT) and MPI. EF was 68 ± 5 % in gr. I, 69 ± 5 % in gr. II, 69 ± 4 % in gr. III. LV mass index was 122 ± 11 g/m2 in gr. I, 148 ± 13 g/m2 in gr. II and 118 ± 13 g/m2 in gr. III. Concentric LVH was detected in gr. II (relative wall thickness = 0.49 ± 0.8). LV septal and lateral MPI were abnormal in both hypertensive groups (p < 0.0001). Septal MPI was correlated moderately with septal wall thickness (r = 0.447, p < 0.001).

CONCLUSIONS

LV diastolic dysfunction becomes more severe in septal wall than lateral wall in hypertensive LVH. Septal myocardial performance is more dominantly affected by hypertension possibly due to earlier septal involvement in disease course. Septal MPI is correlated moderately with septal wall thickness.

Three-Dimensional Echocardiographic Evaluation of Mitral Apparatus during Preload Manipulation in Patients with Hypertrophic Cardiomyopathy

BACKGROUND

The three-dimensional (3D) dynamic change of mitral geometry during preload manipulation has not been fully investigated. We investigated how preload manipulation affected the mitral apparatus geometry in hypertrophic cardiomyopathy (HCM) patients using 3D echocardiography.

METHODS AND RESULTS

Twenty five HCM patients, thirteen with obstructive HCM (HOCM) and twelve with nonobstructive HCM (HNCM), and six healthy controls were studied. Subjects underwent 3D echocardiography during rest, leg raising, the Valsalva maneuver, and the Valsalva maneuver after nitroglycerin intake (NTG-Valsalva). Left ventricular outflow tract (LVOT) pressure gradients, mitral annular area, annular circumference, and the tenting volume of the mitral leaflets were measured. Standardized annular area significantly decreased during the NTG-Valsalva maneuver in all 3 groups (▵2.23 mm(2) /m(2) in control, P = 0.031; ▵0.46 mm(2) /m(2) in HNCM, P = 0.012; ▵1.3 mm(2) /m(2) in HOCM, P = 0.013). Standardized annular area decrease during the Valsalva maneuver alone was more prominent in HNCM patients (▵0.57 mm(2) /m(2) , P = 0.009) than HOCM patients (▵0.3 mm(2) /m(2) , P = 0.094). Standardized mitral tenting volume during the NTG-Valsalva maneuver significantly decreased only in HOCM patients (▵1.18 mm(3) /m(2) , P = 0.046).

CONCLUSION

Decreased mitral annular area and changes in leaflets tenting volume during preload reduction might affect the development of LVOT obstruction. Our data suggest the importance of preserving the saddle-shaped of the mitral annulus in management of HCM with LVOT obstruction.

Stress-induced regional features of left ventricle is related to pathogenesis of clinical conditions with both acute and chronic stress

Tako-tsubo cardiomyopathy is a relatively newly described acute and reversible left ventricular (LV) dysfunction triggered by emotional stress. The disease is associated with excessive sympathetic stimulation, microvascular dysfunction and abnormal myocardial tissue metabolism. Recently, we have pointed out that tako-tsubo cardiomyopathy may be associated with particular LV features which are also described by quantitative echocardiographic methods in hypertensive heart disease. The patients with acute or chronic stress can be presented clinically by stress-induced LV hypercontractility of LV base, relevant LV outflow tract obstruction and narrowed cavity. Recent observations also have confirmed the possibility of association of both acute and chronic conditions in a clinical presentation of the patients. Therefore, we believe that the presence of both resistance and hypercontractile response of LV base to stress induction compared with midapical region in clinical conditions with acute or chronic stress is important in the disease process.

Current cardiac imaging techniques for detection of left ventricular mass

Estimation of left ventricular (LV) mass has both prognostic and therapeutic value independent of traditional risk factors. Unfortunately, LV mass evaluation has been underestimated in clinical practice. Assessment of LV mass can be performed by a number of imaging modalities. Despite inherent limitations, conventional echocardiography has fundamentally been established as most widely used diagnostic tool. 3-dimensional echocardiography (3DE) is now feasible, fast and accurate for LV mass evaluation. 3DE is also superior to conventional echocardiography in terms of LV mass assessment, especially in patients with abnormal LV geometry. Cardiovascular magnetic resonance (CMR) and cardiovascular computed tomography (CCT) are currently performed for LV mass assessment and also do not depend on cardiac geometry and display 3-dimensional data, as well. Therefore, CMR is being increasingly employed and is at the present standard of reference in the clinical setting. Although each method demonstrates advantages over another, there are also disadvantages to receive attention. Diagnostic accuracy of methods will also be increased with the introduction of more advanced systems. It is also likely that in the coming years new and more accurate diagnostic tests will become available. In particular, CMR and CCT have been intersecting hot topic between cardiology and radiology clinics. Thus, good communication and collaboration between two specialties is required for selection of an appropriate test.

[The role of real-time three-dimensional echocardiography in the evaluation of hypertrophic cardiomyopathy]

Hypertrophic cardiomyopathy is a relatively common hereditary disorder, which is associated with cardiac morphologic and functional alterations. Echocardiography is a non-invasive, simple and easy-to-learn method to evaluate patients with cardiomyopathy. The aim of this review paper is to demonstrate the possible diagnostic role of one of the newest echocardiographic development, the real-time 3-dimensional echocardiography in the evaluation of hypertrophic cardiomyopathy.

Single photon emission computed tomography: an alternative imaging modality in left ventricular evaluation

Various diagnostic imaging modalities have been used for quantitative left ventricular (LV) parameters. Because of the suboptimal value of the most widely used technology, two-dimensional (2D) echocardiography, 3D ultrasonographic imaging has improved accuracy for LV volume and function. Single photon emission computed tomography (SPECT) is another diagnostic method where LV volumetric and functional parameters can be accurately provided by gated myocardial perfusion tomographic slices. First pass radionuclide venticulography is another imaging modality which has some practical limitations. Despite lower ejection fraction (EF) values compared with invasive approach, noninvasive techniques are accurate in determination of normal and depressed EF. Noninvasive techniques with 3D approach including gated SPECT are beneficial for not only global but also regional LV evaluation. It has been mentioned that the slight difference between echocardiography and SPECT could be caused by the diverse population studied. The results of diagnostic stress tests support that SPECT is feasible to use in evaluation of LV volume and functional analysis. Magnetic resonance imaging is an expensive modality to use routinely, but it preserves its importance in selected patients for providing precise LV geometric data.

Takotsubo cardiomyopathy may be associated with cardiac geometric features as observed in hypertensive heart disease

Takotsubo cardiomyopathy is a clinical entity with a relatively new described acute and reversible left ventricular (LV) dysfunction triggered by emotional stress. Different observations have represented that takotsubo cardiomyopathy may be associated with similar LV myocardial geometry as described by novel quantitative echocardiographic methods in hypertensive heart disease. Therefore, acute emotional stress in takotsubo cardiomyopathy or chronic stress by increased afterload in hypertension possibly represents similar morphologic and functional features on the basis of heart.

Demonstration of left ventricular outflow tract eccentricity by real time 3D echocardiography: implications for the determination of aortic valve area

BACKGROUND

Determination of the left ventricular outflow tract cross-sectional area (ALVOT) is necessary for calculating aortic valve area (AVA) by echocardiography using the continuity equation (CE). In the commonly applied form of CE, pir(2) is used to estimate ALVOT utilizing the assumptions that LVOT is round and the parasternal long axis (PLAX) plane bisects LVOT. Imaging LVOT using real time 3D echocardiography (RT3DE) eliminates the need for these assumptions. We tested the hypothesis that LVOT is round based on a formula for eccentricity.

METHODS AND RESULTS

In 53 patients, 2D echocardiography (2DE) and RT3DE were acquired. ALVOT was calculated by 2DE using pir(2) (ALVOT-2D). Using RT3DE, ALVOT planimetry was performed immediately beneath the aortic valve (ALVOT-3Dplan). Eccentricity Index (EI) was calculated using the shortest and longest LVOT diameters. The long axis was measured to be larger by 0.53 cm +/- 0.36 (P < 0.005). The median EI was 0.20 (0.00-0.54), indicating that half the subjects had at least a 20% difference between the major and minor diameters. ALVOT-3Dplan was larger than ALVOT-2D (3.73 +/- 0.95 cm(2) vs. 3.18 +/- 0.73 cm(2); P < 0.001) by paired analysis. Using the equation of an ellipse (piab), ALVOT-3Dellip was 3.57 +/- 0.95 resulting in improved agreement with ALVOT-3Dplan.

CONCLUSIONS

In our small patient sample with normal aortic valves, we showed the LVOT shape is usually not round and frequently, elliptical. Incorrectly assuming a round LVOT underestimated the ALVOT-3Dplan and consequently the AVA by 15%. Investigating the LVOT in aortic stenosis is warranted to evaluate whether RT3DE may improve measurement of AVA.

Relation between number of component views and accuracy of left ventricular mass determined by three-dimensional echocardiography

Three-dimensional echocardiography (3DE) allows the accurate determination of left ventricular (LV) mass, but the optimal number of component or extracted 2-dimensional (2D) image planes that should be used to calculate LV mass is not known. This study was performed to determine the relation between the number of 2D image planes used for 3DE and the accuracy of LV mass, using cardiovascular magnetic resonance (CMR) imaging as the reference standard. Three-dimensional echocardiography data sets were analyzed using 4, 6, 8, 10 and 20 component 2D planes as well as biplane 2D echocardiography and CMR in 25 subjects with a variety of LV pathologies. Repeated-measures analysis of variance and the Bland-Altman method were used to compare measures of LV mass. To further assess the potential clinical impact of reducing the number of component image planes used for 3DE, the number of discrepancies between CMR and each of the 3DE estimates of LV mass at prespecified levels (i.e., > or =5%, > or =10%, and > or =20% difference from CMR LV mass) was tabulated. The mean LV mass by magnetic resonance imaging was 177 +/- 56 g (range 91 to 316). Biplane 2-dimensional echocardiography significantly underestimated CMR LV mass (p <0.05), but LV mass by 3DE was not statistically different from that by CMR regardless of the number of planes used. However, error variability and Bland-Altman 95% confidence intervals decreased with the use of additional image planes. In conclusion, transthoracic 3DE measures LV mass more accurately than biplane 2-dimensional echocardiography when > or =6 component 2D image planes are used. The use of >6 planes further increases the accuracy of 3DE, but at the cost of greater analysis time and potentially increased scanning times.

Three-Dimensional Echocardiographic Evaluation of the Heart Chambers: Size, Function, and Mass

The major advantage of three-dimensional (3D) ultrasound imaging of the heart is the improvement in the accuracy of the echocardiographic evaluation of cardiac chamber volumes, which is achieved by eliminating the need for geometric modeling and the errors caused by foreshortened 2D views. In this article, we review the literature that has provided the scientific basis for the clinical use of 3D ultrasound imaging of the heart in the assessment of cardiac chamber size, function, and mass, and discuss its potential future applications.

Effect of dobutamine stress on basal septal tissue dynamics in hypertensive patients with basal septal hypertrophy

Left ventricular outflow tract (LVOT) obstruction has been classically observed in hypertrophic cardiomyopathy in which the LVOT obstruction is associated with asymmetric septal hypertrophy producing a systolic pressure gradient across the LVOT. Basal septal hypertrophy (BSH) with hypertension may result in dynamic LVOT obstruction as well. It was suggested that regional hypertrophy may be related to enhanced ventricular dynamics.

Quantitative assessment of right ventricular geometric remodeling in pulmonary hypertension secondary to left-sided heart disease using real-time three-dimensional echocardiography

We assessed right ventricular (RV) geometric remodeling quantitatively in patients with chronic pulmonary hypertension (PH) secondary to left-sided heart disease using real-time 3-dimensional echocardiography by comparing segmental and total volumes to that in normal subjects. The comparison result revealed that RV geometric remodeling in the PH group mainly occurred at the basal, mid-basal, and mid-segments. Total RV end-diastolic and end-systolic volumes in the PH group were significantly larger than that in normal subjects.

Do variable age-related secondary factors affect ventricular geometry in hypertrophic cardiomyopathy?

The relationship between cardiac shape and the age of patients with hypertrophic cardiomyopathy (HCM) has been established, and echocardiography has been accepted as the best method to quantitate ventricular cavity geometry. Recently, real-time three-dimensional volumetric data have demonstrated that children and young, middle-aged, and elderly patients with HCM have different morphologic and prognostic characteristics. This review discusses the importance of phenotypic expression and describes secondary factors that may affect ventricular cavity geometry during the progression of HCM.