Tissue Doppler imaging for the evaluation of patients with hypertrophic cardiomyopathy

Structural alterations in rat myocardium induced by chronic l-arginine and l-NAME supplementation

Structural changes affecting cardiomyocyte function may contribute to the pathophysiological remodeling underlying cardiac function impairment. Recent reports have shown that endogenous nitric oxide (NO) plays an important role in this process. In order to examine the role of NO in cardiomyocyte remodeling, male rats were acclimated to room temperature (22 ± 1 °C) or cold (4 ± 1 °C) and treated with 2.25% l-arginine·HCl or 0.01% l-NAME (Nω-nitro-l-arginine methyl ester)·HCl for 45 days. Untreated groups served as controls. Right heart ventricles were routinely prepared for light microscopic examination. Stereological estimations of volume densities of cardiomyocytes, surrounding blood vessels and connective tissue, as well as the morphometric measurements of cardiomyocyte diameters were performed. Tissue sections were also analyzed for structural alterations. We observed that both l-arginine and l-NAME supplementation induced cardiomyocyte hypertrophy, regardless of ambient temperature. However, cardiomyocyte hypertrophy was associated with fibrosis and extra collagen deposition only in the l-NAME treated group. Taken together, our results suggest that NO has a modulatory role in right heart ventricle remodeling by coordinating hypertrophy of cardiomyocytes and fibrous tissue preventing cardiac fibrosis.

Age-related changes in familial hypertrophic cardiomyopathy phenotype in transgenic mice and humans

β-myosin heavy chain mutations are the most frequently identified basis for hypertrophic cardiomyopathy (HCM). A transgenic mouse model (αMHC(403)) has been extensively used to study various mechanistic aspects of HCM. There is general skepticism whether mouse and human disease features are similar. Herein we compare morphologic and functional characteristics, and disease evolution, in a transgenic mouse and a single family with a MHC mutation. Ten male αMHC(403) transgenic mice (at t-5 weeks, -12 weeks, and -24 weeks) and 10 HCM patients from the same family with a β-myosin heavy chain mutation were enrolled. Morphometric, conventional echocardiographic, tissue Doppler and strain analytic characteristics of transgenic mice and HCM patients were assessed. Ten male transgenic mice (αMHC(403)) were examined at ages -5 weeks, -12 weeks, and -24 weeks. In the transgenic mice, aging was associated with a significant increase in septal (0.59±0.06 vs. 0.64±0.05 vs. 0.69±0.11 mm, P<0.01) and anterior wall thickness (0.58±0.1 vs. 0.62±0.07 vs. 0.80±0.16 mm, P<0.001), which was coincident with a significant decrease in circumferential strain (-22%±4% vs. -20%±3% vs. -19%±3%, P=0.03), global longitudinal strain (-19%±3% vs. -17%±2% vs. -16%±3%, P=0.001) and E/A ratio (1.9±0.3 vs. 1.7±0.3 vs. 1.4±0.3, P=0.01). The HCM patients were classified into 1st generation (n=6; mean age 53±6 years), and 2nd generation (n=4; mean age 32±8 years). Septal thickness (2.2±0.9 vs. 1.4±0.1 cm, P<0.05), left atrial (LA) volume (62±16 vs. 41±5 mL, P=0.03), E/A ratio (0.77±0.21 vs. 1.1±0.1, P=0.01), E/e' ratio (25±10 vs. 12±2, P=0.03), global left ventricular (LV) strain (-14%±3% vs. -20%±3%, P=0.01) and global LV early diastolic strain rate (0.76±0.17 s(-1) vs. 1.3±0.2 s-1, P=0.01) were significantly worse in the older generation. In β-myosin heavy chain mutations, transgenic mice and humans have similar progression in morphologic and functional abnormalities. The αMHC(403) transgenic mouse model closely recapitulates human disease.

Two-dimensional strain profiles in patients with physiological and pathological hypertrophy and preserved left ventricular systolic function: a comparative analyses

OBJECTIVE

This study was designed to examine the utility of two-dimensional strain (2DS) or speckle tracking imaging to typify functional adaptations of the left ventricle in variant forms of left ventricular hypertrophy (LVH).

DESIGN

Cross-sectional study.

SETTING

Urban tertiary care academic medical centres.

PARTICIPANTS

A total of 129 subjects, 56 with hypertrophic cardiomyopathy (HCM), 34 with hypertensive left ventricular hypertrophy (H-LVH), 27 professional athletes with LVH (AT-LVH) and 12 healthy controls in sinus rhythm with preserved left ventricular systolic function.

METHODS

Conventional echocardiographic and tissue Doppler examinations were performed in all study subjects. Bi-dimensional acquisitions were analysed to map longitudinal systolic strain (automated function imaging, AFI, GE Healthcare, Waukesha, Wisconsin, USA) from apical views.

RESULTS

Subjects with HCM had significantly lower regional and average global peak longitudinal systolic strain (GLS-avg) compared with controls and other forms of LVH. Strain dispersion index, a measure of regional contractile heterogeneity, was higher in HCM compared with the rest of the groups. On receiver operator characteristics analysis, GLS-avg had excellent discriminatory ability to distinguish HCM from H-LVH area under curve (AUC) (0.893, p<0.001) or AT-LVH AUC (0.920, p<0.001). Tissue Doppler and LV morphological parameters were better suited to differentiate the athlete heart from HCM.

CONCLUSIONS

2DS (AFI) allows rapid characterisation of regional and global systolic function and may have the potential to differentiate HCM from variant forms of LVH.

Characterizing myocardial deformation in patients with left ventricular hypertrophy of different etiologies using the strain distribution obtained by magnetic resonance imaging

INTRODUCTION AND OBJECTIVES

In hypertrophic cardiomyopathy (HCM), it has been suggested that regional fiber disarray produces segments that exhibit no or severely reduced deformation, and that these segments are distributed nonuniformly within the left ventricle (LV). This contrasts with observations in other types of hypertrophy, such as in athlete's heart or hypertensive left ventricular hypertrophy (HLVH), in which abnormal cardiac deformation may exist but the reduction is not so severe that some segments exhibit no deformation. Our aim was to use the strain distribution to study deformation in HCM.

METHODS

We used tagged magnetic resonance imaging to reconstruct LV systolic deformation in 12 controls, 10 athletes, 12 patients with HCM, and 10 patients with HLVH. Deformation was quantified using a fast nonrigid registration algorithm and peak radial and circumferential systolic strain values were determined in 16 LV segments.

RESULTS

Patients with HCM had significantly lower average strain values than individuals in other groups. However, while the deformation observed in healthy subjects and HLVH patients clustered around the mean, in HCM patients, segments with normal contraction coexisted with segments exhibiting no or significantly reduced deformation, which resulted in a greater heterogeneity of strain values. Moreover, some nondeforming segments were observed even when fibrosis and hypertrophy were absent.

CONCLUSIONS

The strain distribution characterized specific patterns of myocardial deformation in patients with LVH due to different etiologies. Patients with HCM had significantly lower mean strain values and a greater heterogeneity in strain values than controls, athletes and HLVH patients. In addition, they had nondeforming regions.

The diastolic stress test: a new approach to an old problem

The evaluation of ischemic heart disease is the cornerstone of clinical Cardiology. Although there are many means of ischemic evaluation, all are with their own limitations. While perfusion-based studies are highly sensitive, they lack specificity. Conversely, systolic wall motion analysis with echocardiography tends to have high specificity; however, the sensitivity may be limited by short duration of systolic abnormalities when present. With the advent of Doppler echocardiography, and more specifically tissue Doppler imaging, and strain and strain rate imaging, a more comprehensive evaluation of the left ventricular function is available, including diastole. Diastolic abnormalities in the setting of ischemia are now being studied using these new parameters and have been suggested as a reliable marker of ischemia. Exercise-induced abnormalities in diastolic parameters have improved sensitivities and specificities over traditional stress testing and persist longer than systolic abnormalities. A review of the medical literature regarding the subject will be discussed here.

Assessment of myocardial mechanics using speckle tracking echocardiography: fundamentals and clinical applications

The authors summarize the recent developments in speckle-tracking echocardiography (STE), a relatively new technique that can be used in conjunction with two-dimensional or three-dimensional echocardiography for resolving the multidirectional components of left ventricular (LV) deformation. The tracking system is based on grayscale B-mode images and is obtained by automatic measurement of the distance between 2 pixels of an LV segment during the cardiac cycle, independent of the angle of insonation. The integration of STE with real-time cardiac ultrasound imaging overcomes some of the limitations of previous work in the field and has the potential to provide a unified framework to more accurately quantify the regional and global function of the left ventricle. STE holds promise to reduce interobserver and intraobserver variability in assessing regional LV function and to improve patient care while reducing health care costs through the early identification of subclinical disease. Following a brief overview of the approach, the authors pool the initial observations from clinical studies on the development, validation, merits, and limitations of STE.

Methods and reliability of tissue Doppler imaging for assessment of left ventricular radial wall motion in horses

BACKGROUND

Noninvasive assessment of left ventricular (LV) function is incompletely studied in horses.

OBJECTIVES

The goals of this study were to investigate the feasibility, techniques, and reliability of tissue Doppler imaging (TDI) for characterization of LV radial wall motion in healthy horses.

ANIMALS

Three Standardbreds, 3 Thoroughbreds; age 8-14 years; body weight 517-606 kg.

METHODS

Repeated echocardiographic examinations were performed by 2 observers in unsedated horses using TDI. Test reliability was determined by estimating measurement variability, within-day interobserver variability, and between-day interobserver and intraobserver variability of all echocardiographic variables. Variability was expressed as coefficient of variation (CV) and the absolute value below which the difference between 2 measurements will lie with 95% probability.

RESULTS

Assessment of LV radial wall motion by TDI was feasible in all horses. Measurement variabilities were very low (CV < 5%) to low (CV 5-15%) for most variables. Within-day interobserver variability as well as between-day interobserver and intraobserver variabilities were low to moderate (CV 16-25%) for most variables. All pulsed-wave TDI variables of systolic LV function showed very low to low variability, whereas some of the variables of LV diastolic and LA function showed moderate to high (CV > 25%) variability. Pulsed-wave TDI variables appeared more reliable than color TDI variables.

CONCLUSIONS AND CLINICAL IMPORTANCE

Measurement of TDI indices of LV function is feasible and reliable in adult Standardbred and Thoroughbred horses. The clinical relevance of LV function assessment by TDI remains to be determined.

Echocardiographic strain imaging to assess early and late consequences of sarcomere mutations in hypertrophic cardiomyopathy

BACKGROUND

Genetic testing identifies sarcomere mutation carriers (G+) before clinical diagnosis of hypertrophic cardiomyopathy (HCM), allowing characterization of initial disease manifestations. Previous studies demonstrated that impaired relaxation develops before left ventricular hypertrophy (LVH). The precise impact of sarcomere mutations on systolic function in early and late disease is unclear.

METHODS AND RESULTS

Comprehensive echocardiography with strain imaging was performed on 146 genotyped individuals with mutations in 5 sarcomere genes. Contractile parameters were compared in 68 preclinical (G+/LVH-), 40 overt (G+/LVH+) subjects with HCM, and 38 mutation (-) normal control relatives. All subjects had normal left ventricular ejection fraction. In preclinical HCM, global and regional peak systolic strain (epsilon(sys)) and longitudinal systolic strain rate were not significantly different from controls, but early diastolic mitral annular velocity (Ea) was reduced by 13%. In overt HCM, there was a significant 27% and 14% decrease in global longitudinal epsilon(sys) and systolic strain rate, respectively, compared with both preclinical HCM and controls (P<0.013 for all comparisons), and a 33% reduction in Ea.

CONCLUSIONS

Sarcomere mutations have disparate initial effects on diastolic and systolic functions. Preclinical HCM is characterized by impaired relaxation but preserved systolic strain. In contrast, both diastolic and longitudinal systolic abnormalities are present in overt disease despite normal ejection fraction. We propose that diastolic dysfunction is an early consequence of sarcomere mutations, whereas systolic dysfunction results from mutations combined with subsequent pathological remodeling. Identifying mechanistic pathways triggered by these mutations may begin to reshape the clinical paradigm for treatment, based on early diagnosis and disease prevention.

A standard echocardiographic and tissue Doppler study of morphological and functional findings in children with hypertrophic cardiomyopathy compared to those with left ventricular hypertrophy in the setting of Noonan and LEOPARD syndromes

BACKGROUND

Several clinical and echocardiographic studies describe morphological and functional findings in patients with hypertrophic cardiomyopathy. Less is known regarding morphological and functional characteristics of the left ventricular hypertrophy found in the setting of the Noonan and LEOPARD syndromes.

OBJECTIVE

To compare non-invasively the morphological and functional findings potentially affecting symptoms and clinical outcome in children with hypertrophic cardiomyopathy as opposed to Noonan and LEOPARD syndromes.

PATIENTS AND METHODS

We studied by echo-Doppler 62 children with left ventricular hypertrophy, dividing them into two subgroups matched for age and body surface area. The first group, of 45 patients with a mean age of 7.5 +/- 5.2 years and body surface area of 0.9 +/- 0.44 mq, had idiopathic hypertrophic cardiomyopathy. The second group, of 17 patients, all had left ventricular hypertrophy in the setting of Noonan or LEOPARD syndromes. Their mean age was 6.6 +/- 5 years, and body surface area was 0.8 +/- 0.36 mq. In all patients, we assessed the left ventricular maximal mural thickness, expressed as a Z-score, along with any obstructions in the left and right ventricular outflow tracts. In addition, to define left ventricular diastolic function, we used mitral flow and pulsed Tissue Doppler to record the Ea, Aa, Ea/Aa, E/Ea indexes in the apical 4-chamber view at the lateral corner of the mitral annulus. We also measured the diameters of the coronary arteries in the diastolic frame.

RESULTS

Compared to those with hypertrophic cardiomyopathy, those with syndromic left ventricular hypertrophy showed a significantly increased Z-score for mural thickness, and a higher prevalence of obstruction in the left ventricular outflow tract. In addition, the patients with Noonan or LEOPARD syndromes showed a significantly decrease of Ea and increase of Aa, with a decreased Ea/Aa ratio, all suggestive of left ventricular abnormal relaxation. Moreover, the E/Ea ratio was significantly increased in these patients. The presence of right ventricular hypertrophy, mainly associated with dynamic obstruction in the outflow tract, was detected in only 5 of the 17 patients with Noonan or LEOPARD syndromes, as was dilation of the coronary arteries.

CONCLUSIONS

Compared to children with hypertrophic cardiomyopathy, those with left ventricular hypertrophy in the setting of Noonan or LEOPARD syndromes show more ventricular hypertrophy and diastolic dysfunction, due to both abnormal relaxation and reduced compliance. They also exhibit an increased prevalence of obstruction of the left ventricular outflow tract, along with dynamic obstruction of the right ventricular outflow tract and dilated coronary arteries. These morphological and functional findings could explain the different symptoms and clinical events, and potentially define the more appropriate therapeutic options in children with left ventricular hypertrophy of different aetiology.

Clinical significance of tissue Doppler imaging in patients with hypertrophic cardiomyopathy

BACKGROUND

A transmitral E/septal Ea ratio > or =15 is a predictor of adverse outcome in cardiac disease, so it was hypothesized that a septal E/Ea >/=15 would predict the risk of adverse outcome, including sustained ventricular tachycardia (VT), cardiac arrest, implantable cardioverter defibrillator (ICD) discharge, or sudden death (SD) in patients with hypertrophic cardiomyopathy (HCM).

METHODS AND RESULTS

The study group comprised 96 consecutive patients with HCM (median age 53 years) who completed all noninvasive tests for risk stratification. The endpoint of the study was defined as death, cardiac arrest, documented sustained VT, or ICD-discharge. The median follow-up was 20.6 months. All patients were alive at the end of follow-up, although 8 patients had reached the endpoint during the study period. The variables that were predictive of adverse clinical outcome were family history of premature SD (p=0.03), syncope (p<0.001), maximum wall thickness > or =3 cm (p=0.02), and septal E/Ea > or =15 (p<0.001). In a stepwise multivariable model the only independent prognostic indicator was a septal E/Ea > or =15 (relative risk 0.26, 95% confidence interval 0.2-0.58, p<0.001). The cumulative event-free survival rate was 78.9% in patients with septal E/Ea > or =15, and 100% in patients with septal E/Ea <15 (p=0.0003).

CONCLUSIONS

Septal E/Ea > or =15 predicts patients with HCM who are at risk of sustained VT, cardiac arrest, ICD-discharge, or SD. (Circ J 2007; 71: 897 - 903).

Phenotypic spectrum and clinical characteristics of apical hypertrophic cardiomyopathy: multicenter echo-Doppler study

OBJECTIVES

The aim of this study was to define the phenotypic spectrum of apical hypertrophic cardiomyopathy (ApHCM) and clinical characteristics pertaining to identified subtypes.

METHODS

In 182 consecutive ApHCM patients (58.9 +/- 11.2 years; 142 men) with left ventricular ejection fraction > or =50%, we measured end-diastolic wall thickness of all 16 left ventricular segments to determine patterns of hypertrophy. Echo-Doppler parameters, electrocardiography patterns, and clinical findings were analyzed.

RESULTS

ApHCM was classified into three types as pure focal (n = 81), pure diffuse (n = 70) and mixed type (n = 31) according to patterns of hypertrophy. Incidence of atrial fibrillation (5% for pure focal vs. 11% for pure diffuse vs. 23% for mixed type, p < 0.05) and left atrial volume index (30.9 +/- 11.8, 35.7 +/- 14.8, and 41.3 +/- 15.9 ml/m(2), respectively, p < 0.001) were significantly different among subtypes. Peak systolic (6.6 +/- 1.0 vs. 6.3 +/- 1.2 vs. 5.9 +/- 1.1 cm/s, respectively, p < 0.05), diastolic (5.1 +/- 1.8 vs. 5.0 +/- 1.2 vs. 4.1 +/- 1.3 cm/s, respectively, p < 0.05) mitral annular velocity, E/E' (13.3 +/- 4.2 vs. 13.7 +/- 5.4 vs. 16.1 +/- 6.1, respectively, p < 0.05) were also significantly different.

CONCLUSIONS

ApHCM contains three morphologically distinct phenotypes and detailed subtyping is important in the prediction of development of atrial fibrillation, left atrial volume index and left ventricular longitudinal function.

Utility of Doppler echocardiography and tissue Doppler imaging in the estimation of diastolic function in heart failure with normal ejection fraction: a comparative Doppler-conductance catheterization study

BACKGROUND

Various conventional and tissue Doppler echocardiographic indexes were compared with pressure-volume loop analysis to assess their accuracy in detecting left ventricular (LV) diastolic dysfunction in patients with heart failure with normal ejection fraction (HFNEF).

METHODS AND RESULTS

Diastolic dysfunction was confirmed by pressure-volume loop analysis obtained by conductance catheter in 43 patients (19 men) with HFNEF. Their Doppler indexes were compared with those of 12 control patients without heart failure symptoms and with normal ejection fraction. Invasively measured indexes for diastolic relaxation (tau, dP/dt(min)), LV end-diastolic pressure, and LV end-diastolic pressure-volume relationship (stiffness, b [dP/dV], and stiffness constant, beta) were correlated with several conventional mitral flow and tissue Doppler imaging indexes. Conventional Doppler indexes correlated moderately with the degree of LV relaxation index, tau (E/A: r=-0.36, P=0.013; isovolumic relaxation time: r=0.31, P=0.040) and b (deceleration time: r=0.39, P=0.012) but not with beta, in contrast to the tissue Doppler imaging indexes E'/A'(lateral) (r=-0.37, P=0.008) and E/E'(lateral) (r=0.53, P<0.001). Diastolic dysfunction was detected in 70% of the HFNEF patients by mitral flow Doppler but in 81% and 86% by E'/A'(lateral), and E/E'(lateral), respectively.

CONCLUSIONS

Of all echocardiographic parameters investigated, the LV filling index E/E'(lateral) was identified as the best index to detect diastolic dysfunction in HFNEF in which the diagnosis of diastolic dysfunction was confirmed by conductance catheter analysis. We recommend its use as an essential tool for noninvasive diagnostics of diastolic function in patients with HFNEF.

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.

Regression of dilated-hypokinetic hypertrophic cardiomyopathy by biventricular cardiac pacing

The evolution of hypertrophic cardiomyopathy (HCM) towards dilatation and hypokinesis is an increasingly recognized complication with a high incidence of adverse outcomes, including sudden cardiac death, requiring defibrillator implantation and cardiac transplantation. It is generally regarded as the irreversible 'burnt-out' end-stage manifestation of HCM. We report one of the first cases of profound regression of the dilated-hypokinetic state by the application of biventricular pacing and cardiac resynchronization therapy (CRT). Reviewing the literature on the role of pacing in HCM and the energetic rationale for CRT in HCM prompts us to suggest that further systematic studies are needed urgently to assess the role of CRT in HCM variants.

Noninvasive cardiac imaging in patients with hypertrophic cardiomyopathy

Hypertrophic cardiomyopathy (HCM) is the most common inherited cardiomyopathy and the most common cause of cardiac death in young athletes in the U.S. Noninvasive imaging plays an important role in detecting the disease, understanding its pathophysiology, and selecting as well as guiding appropriate therapy. In this review, we discuss the existing methodology with emphasis on current and emerging clinical applications in patients with HCM.

The usefulness of Doppler myocardial imaging in the study of the athlete's heart and in the differential diagnosis between physiological and pathological ventricular hypertrophy

Athlete's heart is a cardiac adaptation to long-term, intensive training, which includes changes as increased ventricular cavity diameters, wall thickness and mass, produced with a degree consistent with sports activities and exercise programs. The Doppler myocardial imaging (DMI) permits characterization of the velocities of each ventricular myocardial segment by placing the sample volume at the center of the cardiac muscle. Even if the standard two-dimensional (2D) echocardiography represents an irreplaceable method in the evaluation of cardiac adaptations to physical exercise, the data currently available suggests the usefulness of DMI in the assessment of the myocardial systolic and diastolic functions of the athlete's heart. In particular, an athlete's left ventricular hypertrophy is characterized by a "supernormal" DMI pattern, with increased myocardial early-diastolic velocity. Therefore, DMI analysis in the trained subject has demonstrated interesting prospective for: (1) the differential diagnosis from pathological, both, left and right ventricular hypertrophy; (2) the prediction of cardiac performance during physical effort; (3) the evaluation of the biventricular interaction; (4) the analysis of the myocardial adaptations to various training protocols; and (5) the early identification of specific genotypes associated with cardiomyopathies. On this ground, a combined use of standard 2D echo and DMI may be taken into account for a valid noninvasive and easy-repeatable evaluation of both physiological and pathological ventricular hypertrophies.

The athleteʼs heart and hypertrophic cardiomyopathy: two conditions which may be misdiagnosed and coexistent. Which parameters should be analysed to distinguish one disease from the other?

According to the statements from the International Cardiological Committees on Eligibility for Sports, athletes with a clinical diagnosis of hypertrophic cardiomyopathy (HCM) should be excluded from most competitive sports, with the possible exception of those of low intensity. Clinical distinctions between physiological athlete's heart and pathological conditions such as HCM have critical implications especially for trained athletes. Even if the standard two-dimensional echocardiography represents an irreplaceable method in the evaluation of cardiac adaptations to physical exercise, the data currently available suggest the usefulness of Doppler myocardial imaging (DMI) in the assessment of the myocardial systolic and diastolic function of the athlete's heart. On this ground, the combined use of standard two-dimensional echocardiography and DMI may be taken into account for a valid, non-invasive and easily repeatable evaluation of both physiological and pathological ventricular hypertrophy, and in selecting a subgroup of HCM patients at higher risk of cardiac events. In particular, DMI analysis in the trained individual has demonstrated an interesting opportunity for: (1) the differential diagnosis from pathological left ventricular hypertrophy due to HCM; (2) the prediction of cardiac performance during physical effort; (3) the evaluation of bi-ventricular interaction; (4) the analysis of myocardial adaptations to various training protocols; and (5) the early identification of specific genotypes associated with cardiomyopathies.