Use of pulsed Doppler tissue imaging to assess regional left ventricular diastolic dysfunction in hypertrophic cardiomyopathy

The role of echocardiography for diagnosis and prognostic stratification in hypertrophic cardiomyopathy

Hypertrophic cardiomyopathy (HCM) is the most frequent cardiac disease with genetic substrate, affecting about 0.2-0.5% of the population. While most of the patients with HCM have a relatively good prognosis, some are at increased risk of adverse events. Identifying such patients at risk is important for optimal treatment and follow-up. While clinical and electrocardiographic information plays an important role, echocardiography remains the cornerstone in assessing patients with HCM. In this review, we discuss the role of echocardiography in diagnosing HCM, the key features that differentiate HCM from other diseases and the use of echocardiography for risk stratification in this setting (risk of sudden cardiac death, heart failure, atrial fibrillation and stroke). The use of modern echocardiographic techniques (deformation imaging, 3D echocardiography) refines the diagnosis and prognostic assessment of patients with HCM. The echocardiographic data need to be integrated with clinical data and other information, including cardiac magnetic resonance, especially in challenging cases or when there is incomplete information, for the optimal management of these patients.

Hypertrophic cardiomyopathy: genetics and clinical perspectives

Hypertrophic cardiomyopathy (HCM) is the most common inherited heart disease and defined by unexplained isolated progressive myocardial hypertrophy, systolic and diastolic ventricular dysfunction, arrhythmias, sudden cardiac death and histopathologic changes, such as myocyte disarray and myocardial fibrosis. Mutations in genes encoding for proteins of the contractile apparatus of the cardiomyocyte, such as β-myosin heavy chain and myosin binding protein C, have been identified as cause of the disease. Disease is caused by altered biophysical properties of the cardiomyocyte, disturbed calcium handling, and abnormal cellular metabolism. Mutations in sarcomere genes can also activate other signaling pathways via transcriptional activation and can influence non-cardiac cells, such as fibroblasts. Additional environmental, genetic and epigenetic factors result in heterogeneous disease expression. The clinical course of the disease varies greatly with some patients presenting during childhood while others remain asymptomatic until late in life. Patients can present with either heart failure symptoms or the first symptom can be sudden death due to malignant ventricular arrhythmias. The morphological and pathological heterogeneity results in prognosis uncertainty and makes patient management challenging. Current standard therapeutic measures include the prevention of sudden death by prohibition of competitive sport participation and the implantation of cardioverter-defibrillators if indicated, as well as symptomatic heart failure therapies or cardiac transplantation. There exists no causal therapy for this monogenic autosomal-dominant inherited disorder, so that the focus of current management is on early identification of asymptomatic patients at risk through molecular diagnostic and clinical cascade screening of family members, optimal sudden death risk stratification, and timely initiation of preventative therapies to avoid disease progression to the irreversible adverse myocardial remodeling stage. Genetic diagnosis allowing identification of asymptomatic affected patients prior to clinical disease onset, new imaging technologies, and the establishment of international guidelines have optimized treatment and sudden death risk stratification lowering mortality dramatically within the last decade. However, a thorough understanding of underlying disease pathogenesis, regular clinical follow-up, family counseling, and preventative treatment is required to minimize morbidity and mortality of affected patients. This review summarizes current knowledge about molecular genetics and pathogenesis of HCM secondary to mutations in the sarcomere and provides an overview about current evidence and guidelines in clinical patient management. The overview will focus on clinical staging based on disease mechanism allowing timely initiation of preventative measures. An outlook about so far experimental treatments and potential for future therapies will be provided.

Early segmental relaxation abnormalities in hypertrophic cardiomyopathy for differential diagnostic of patients with left ventricular hypertrophy

BACKGROUND

Hypertrophic cardiomyopathy (HCM) is characterized by asymmetric left ventricular hypertrophy (LVH). However, clinical signs can be subtle and differentiation from other causes of LVH is challenging.

HYPOTHESIS

As diastolic dysfunction (DD) is an early sign in HCM, we aimed to find regional changes in relaxation pattern for differentiation from other entities of LVH.

METHODS

In 148 patients (81 HCM, 55 arterial hypertension (AHT), 12 Fabry disease) and 63 healthy controls, relaxation patterns were assessed using regional tissue Doppler imaging. In 42 HCM patients, myocardial mass and fibrosis were quantified by cardiac magnetic resonance imaging and correlated with relaxation parameters.

RESULTS

In HCM the septal to lateral isovolumic relaxation time (s/l IVRT) ratio was higher (1.5 ± 0.4) compared with AHT (1.1 ± 0.2), Fabry disease (1.0 ± 0.1), and controls (1.1 ± 0.2; P < 0.001), showing 77% sensitivity and 79% specificity to discriminate HCM-related LVH from other entities. The s/l IVRT ratio was independent of global DD in HCM (HCM with DD: 1.5 ± 0.5, n = 52; HCM without DD: 1.5 ± 0.3, n = 29) and remained significantly different from other entities in a subgroup of HCM patients with maximum wall thickness < 20 mm (s/l ratio: 1.5 ± 0.5, n = 28). Regional IVRT did not correlate with the corresponding segmental myocardial mass or amount of fibrosis in cardiac magnetic resonance imaging.

CONCLUSIONS

HCM patients show a prolonged septal IVRT irrespective of the extent of LVH and even before developing global DD. The s/l IVRT ratio is significantly higher in HCM compared with AHT or Fabry disease, thus establishing segmental IVRT analysis as a potential parameter for differential diagnosis in LVH.

Echocardiographic evaluation of left ventricular diastolic function in cats: Hemodynamic determinants and pattern recognition

Left ventricular (LV) diastolic dysfunction is highly prevalent in cats and is a functional hallmark of feline cardiomyopathy. The majority of cats with hypertrophic, restrictive, and dilated cardiomyopathy have echocardiographic evidence of abnormal LV filling, even during the occult (preclinical) phase. Moderate and severe diastolic dysfunction is an indicator of advanced myocardial disease, is associated with clinical signs including exercise intolerance and congestive heart failure, affects outcome, and influences therapeutic decisions. Therefore, identification and quantification of LV diastolic dysfunction are clinically important. Surrogate measures of diastolic function determined by transthoracic two-dimensional, M-mode, and Doppler echocardiographic (DE) methods have been used widely for such purpose. Major functional characteristics of LV diastole, including global function, relaxation and untwist, chamber compliance, filling volume, and the resultant filling pressures can be semi-quantified by echocardiographic methods, and variables retrieved from transmitral flow, pulmonary vein flow, and tissue Doppler recordings are most frequently used. Although there is still a critical lack of well-designed studies in the field, knowledge has steadily accumulated over the past 20 years, reference ranges of diastolic echocardiographic variables have been determined, epidemiological studies have been conducted, and new treatments of diastolic dysfunction in cats have been evaluated. This report will give the reader a summary of the current status in the field of feline diastology with focus on the noninvasive diagnostic methods and interpretation of echocardiographic surrogate measures of LV diastolic function. Lastly, a grading system using a composite of left atrial size and various DE variables potentially useful in the functional classification of LV diastole in cats is introduced.

The multi-modality cardiac imaging approach to the Athlete's heart: an expert consensus of the European Association of Cardiovascular Imaging

The term 'athlete's heart' refers to a clinical picture characterized by a slow heart rate and enlargement of the heart. A multi-modality imaging approach to the athlete's heart aims to differentiate physiological changes due to intensive training in the athlete's heart from serious cardiac diseases with similar morphological features. Imaging assessment of the athlete's heart should begin with a thorough echocardiographic examination.Left ventricular (LV) wall thickness by echocardiography can contribute to the distinction between athlete's LV hypertrophy and hypertrophic cardiomyopathy (HCM). LV end-diastolic diameter becomes larger (>55 mm) than the normal limits only in end-stage HCM patients when the LV ejection fraction is <50%. Patients with HCM also show early impairment of LV diastolic function, whereas athletes have normal diastolic function.When echocardiography cannot provide a clear differential diagnosis, cardiac magnetic resonance (CMR) imaging should be performed.With CMR, accurate morphological and functional assessment can be made. Tissue characterization by late gadolinium enhancement may show a distinctive, non-ischaemic pattern in HCM and a variety of other myocardial conditions such as idiopathic dilated cardiomyopathy or myocarditis. The work-up of athletes with suspected coronary artery disease should start with an exercise ECG. In athletes with inconclusive exercise ECG results, exercise stress echocardiography should be considered. Nuclear cardiology techniques, coronary cardiac tomography (CCT) and/or CMR may be performed in selected cases. Owing to radiation exposure and the young age of most athletes, the use of CCT and nuclear cardiology techniques should be restricted to athletes with unclear stress echocardiography or CMR.

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.

Relationship between Myocardial Extracellular Space Expansion Estimated with Post-Contrast T1 Mapping MRI and Left Ventricular Remodeling and Neurohormonal Activation in Patients with Dilated Cardiomyopathy

OBJECTIVE

Post-contrast T1 values are closely related to the degree of myocardial extracellular space expansion. We determined the relationship between post-contrast T1 values and left ventricular (LV) diastolic function, LV remodeling, and neurohormonal activation in patients with dilated cardiomyopathy (DCM).

MATERIALS AND METHODS

Fifty-nine patients with DCM (mean age, 55 ± 15 years; 41 males and 18 females) who underwent both 1.5T magnetic resonance imaging and echocardiography were enrolled. The post-contrast 10-minute T1 value was generated from inversion time scout images obtained using the Look-Locker inversion recovery sequence and a curve-fitting algorithm. The T1 sample volume was obtained from three interventricular septal points, and the mean T1 value was used for analysis. The N-Terminal pro-B-type natriuretic peptide (NT-proBNP) level was measured in 40 patients.

RESULTS

The mean LV ejection fraction was 24 ± 9% and the post-T1 value was 254.5 ± 46.4 ms. The post-contrast T1 value was significantly correlated with systolic longitudinal septal velocity (s'), peak late diastolic velocity of the mitral annulus (a'), the diastolic elastance index (Ed, [E/e']/stroke volume), LV mass/volume ratio, LV end-diastolic wall stress, and LV end-systolic wall stress. In a multivariate analysis without NT-proBNP, T1 values were independently correlated with Ed (β = -0.351, p = 0.016) and the LV mass/volume ratio (β = 0.495, p = 0.001). When NT-proBNP was used in the analysis, NT-proBNP was independently correlated with the T1 values (β = -0.339, p = 0.017).

CONCLUSION

Post-contrast T1 is closely related to LV remodeling, diastolic function, and neurohormonal activation in patients with DCM.

The role of new echocardiographic techniques in athlete's heart

‘Athlete’s heart’ is a common term for the various adaptive changes induced by intensive exercise. Exercise causes alterations of the heart in hemodynamic response to the increased systemic and pulmonary demand during exercise. The understanding of these adaptations is of high importance, since they may overlap with those caused by pathological conditions. Cardiac imaging assessment of the athlete’s heart should begin with a complete echocardiographic examination. In recent years classical echocardiographic surveys have been joined by new developments: tissue Doppler imaging, strain rate echocardiography, and real-time 3-dimensional echocardiography. This review paper focuses on the importance of these new echocardiographic techniques in delineating the morphological characteristics and functional properties of the athlete’s heart.

Effect of percutaneous mitral balloon valvuloplasty on right ventricular functions in mitral stenosis: short- and mid-term results

OBJECTIVE

To evaluate the short- and mid-term effects of percutaneous mitral balloon valvuloplasty (PMBV) on right ventricular functions in mitral stenosis.

METHODS

A prospective study was conducted in 61 patients who had mitral stenosis in normal sinus rhythm (68% female, age: 42±11-16 years). Right ventricular functions were measured before, immediately after, and at 3 months and 1 year after PMBV by conventional and tissue Doppler echocardiography imaging methods. Additionally, the patients were evaluated in two groups (PAP≥40 mm Hg, n: 46; PAP<40 mm Hg, n: 15) according to the systolic pulmonary artery that was measured by echocardiography prior to PMBV.

RESULTS

Post-PMBV mean gradient, pulmonary artery pressure (PAP), and left atrial size decreased significantly, and the mitral valve area increased significantly in both patient groups. This significance in pulmonary artery pressure was lost at 1 year. The significant post-PMBV increase in tricuspid annular point systolic excursion (TAPSE), systolic velocity, early diastolic velocity, and peak myocardial velocity during isovolumic contraction (IVV), indicating right ventricular functions, disappeared at 1 year. The significant post-PMBV decrease in myocardial performance index (MPI) and late diastolic velocity lost its significance at 1 year. No significant change was observed in myocardial acceleration during isovolumic contraction (IVA). The group with pulmonary hypertension demonstrated significance similar to the results of the overall group. Post-PMBV TAPSE, systolic velocity, early diastolic velocity, IVV, and IVA increased significantly, and this increase was maintained up to 1 year in the group without pulmonary hypertension. MPI and late diastolic velocity maintained their significantly decreased values up to 1 year.

CONCLUSION

The positive effect of PMBV on right ventricular function in the acute period decreases and even disappears in the mid-term in patients developing pulmonary hypertension. Intervention in the patients prior to the development of hypertension is very important for the improvement in right ventricular functions.

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.

A novel and practical cardiovascular magnetic resonance method to quantify mitral annular excursion and recoil applied to hypertrophic cardiomyopathy

BACKGROUND

We have developed a novel and practical cardiovascular magnetic resonance (CMR) technique to evaluate left ventricular (LV) mitral annular motion by tracking the atrioventricular junction (AVJ). To test AVJ motion analysis as a metric for LV function, we compared AVJ motion variables between patients with hypertrophic cardiomyopathy (HCM), a group with recognized systolic and diastolic dysfunction, and healthy volunteers.

METHODS

We retrospectively evaluated 24 HCM patients with normal ejection fractions (EF) and 14 healthy volunteers. Using the 4-chamber view cine images, we tracked the longitudinal motion of the lateral and septal AVJ at 25 time points during the cardiac cycle. Based on AVJ displacement versus time, we calculated maximum AVJ displacement (MD) and velocity in early diastole (MVED), velocity in diastasis (VDS) and the composite index VDS/MVED.

RESULTS

Patients with HCM showed significantly slower median lateral and septal AVJ recoil velocities during early diastole, but faster velocities in diastasis. We observed a 16-fold difference in VDS/MVED at the lateral AVJ [median 0.141, interquartile range (IQR) 0.073, 0.166 versus 0.009 IQR -0.006, 0.037, P < 0.001]. Patients with HCM also demonstrated significantly less mitral annular excursion at both the septal and lateral AVJ. Performed offline, AVJ motion analysis took approximately 10 minutes per subject.

CONCLUSIONS

Atrioventricular junction motion analysis provides a practical and novel CMR method to assess mitral annular motion. In this proof of concept study we found highly statistically significant differences in mitral annular excursion and recoil between HCM patients and healthy volunteers.

Ventricular geometric characteristics and functional benefit of mild right ventricular outflow tract obstruction in patients with significant pulmonary regurgitation after repair of tetralogy of Fallot

BACKGROUND

Right ventricular (RV) outflow tract obstruction (RVOTO) might protect the RV from adverse remodeling caused by significant pulmonary regurgitation (PR) in patients with repaired tetralogy of Fallot (rTOF), but the underlying mechanisms and influences on exercise tolerance remain unclear. This study sought to investigate the impacts from mild RVOTO on ventricular remodeling and exercise capacity in rTOF.

METHODS

Eighty-five rTOF patients with a PR fraction ≥20% were assessed with cardiac magnetic resonance, cardiopulmonary exercise test, and echocardiography. Patients with a peak RVOT pressure gradient 20-50 mmHg were considered to have mild RVOTO (n = 29), while those with a gradient <20 mmHg had isolated PR (n = 56).

RESULTS

Comparing to patients with isolated PR, patients with combined PR and mild RVOTO had smaller RV and RVOT dimension, better RV and left ventricular (LV) ejection fraction (EF), and superior exercise capacity. PR severity and RV mass/volume ratio were similar between these 2 groups. LVEF coupled with RVEF only in patients with isolated PR. In multivariate analysis, smaller RVOT dimension was independently related to smaller RV dimension (P < .001) and higher RVEF (P = .005). Furthermore, mild RVOTO was independently associated with higher peak oxygen consumption (P = .014) and oxygen uptake efficiency slope (P = .005).

CONCLUSIONS

Patients with combined PR and mild RVOTO had better RV remodeling and exercise capacity compared to those with isolated PR. Our findings confirm the benefits from mild residual RVOTO support a policy of conservative RVOTO relief at repair.

The significance of mitral and tricuspid valve systolic lateral annular velocities in the diagnosis of acute pulmonary embolism in patients with chronic heart failure

INTRODUCTION

The diagnosis of acute pulmonary embolism (APE) in patients with chronic heart failure (CHF) remains a difficult task, despite the refinement of imaging techniques. The goal of this study was to assess the value of measuring tricuspid and mitral valve systolic annular velocities in CHF patients with suspected PE by tissue Doppler imaging (TDI).

MATERIAL AND METHODS

The study included 75 patients with previously diagnosed CHF, admitted due to resting dyspnea, with a maximum tricuspid regurgitation pressure gradient (TRPG) of ≥ 35 mm Hg and positive D-dimer assay. Spiral computed tomography (sCT) was performed on all subjects to confirm APE. Acute pulmonary embolism was diagnosed in 35 patients (PE+), and excluded in 40 others (PE-). Tissue Doppler imaging was performed to measure maximum systolic lateral annular velocities in the mitral (SmLV) and tricuspid (SmRV) valves, as well as the SmRV/SmLV ratio.

RESULTS

PE+ subjects were found to have higher SmLV than PE- subjects (6.0 cm/s (2.0-13.8 cm/s) vs. 4.2 cm/s (1.3-9.1 cm/s), p = 0.003). SmRV/SmLV ratios were 1.05 (0.50-2.50) and 1.56 (0.62-4.30), respectively (p < 0.0001). Areas under ROC curves for diagnosis of APE were 0.700 for SmLV and 0.789 for SmRV/SmLV. In multivariate logistic regression analysis, only SmRV/SmLV was statistically significant, with an odds ratio for APE of 6.26 (95% CI: 1.53-25.59; p = 0.009).

CONCLUSIONS

Tissue Doppler imaging of the lateral tricuspid and mitral annuli is a useful clinical tool that can help identify PE in CHF patients. Those patients who fulfill these criteria should be considered for further diagnostic studies to confirm PE.

Left atrial appendage function in prediction of paroxysmal atrial fibrilation in patients with untreated hypertension

Abstract The onset of AF results in a significant increase in mortality rates and morbidity in hypertensive patients and this rhythm disorder exposes patients to a significantly increased risk of cerebral or peripheral embolisms. Tissue Doppler imaging was found to be useful in early detection of myocardial dysfunction in several diseases. It was shown that tissue Doppler analysis of the walls of the left atrial appendage (LAA) can give accurate information about the function of the LAA in hypertensive patients. In this study, we aimed to investigate and identify the specific predictive parameters for the onset of AF in patients with hypertension with tissue Doppler imaging of LAA. We studied age and sex matched 57 untreated hypertensive patients with paroxysmal atrial fibrillation (PAF) and 27 untreated hypertensive subjects without PAF. With transthoracic echocardiography, diastolic mitral A-velocity and LA maximal volume index which reflects reservoir function of left atrium was measured, with transesophageal echocardiography, LAA emptying velocity (LAA-PW D2) and tissue Doppler contracting velocity of LAA (LAA-TDI-D2) were measured. LA maximal volume index of the groups (22.28 ± 3.59 mL/m(2) in Group 1 versus 20.37 ± 3.97 mL/m(2) in Group 2, p = 0.07) and diastolic mitral A-velocity [0.93 (0.59-1.84) m/s in patients with PAF versus 0.90 (0.62-1.76) m/s in patients without PAF, p = 0.26] was not significantly different between study groups, during TEE, LAA-PW D2 (0.31 ± 0.04 m/s in Group 1 versus 0.33 ± 0.03 m/s in Group 2, p = 0.034) and LAA-TDI-D2 (0.18 ± 0.04 m/s in Group 1 versus 0.21 ± 0.05 m/s in Group 2, p = 0.014) were significantly decreased in Group 1. In this study, we found that in hypertensive PAF patients despite normal global LA functions, LAA contracting function was deteriorated. Tissue Doppler analysis of LAA is clinically usefull approach to detect the risk of developing PAF in hypertensives.

Left atrial function assessed by Doppler echocardiography rather than left atrial volume predicts recurrence in patients with paroxysmal atrial fibrillation

BACKGROUND

Paroxysmal atrial fibrillation (PaAF) may present as a single self-terminating episode of atrial fibrillation (AF) or a more persistent form after sinus conversion. We investigated predictors of recurrence in patients with PaAF.

HYPOTHESIS

Left atrial function would be an useful parameter for predicting PaAF recurrence.

METHODS

The study population included 228 PaAF patients (131 males, age 64±14 years) who underwent transthoracic echocardiography immediately after spontaneous sinus conversion at initial AF diagnosis. We followed the study patients for AF recurrence.

RESULTS

AF recurrence was demonstrated in 45 patients (20%, age 68±13 years) after spontaneous sinus conversion. Patients with recurrence had larger left atrial volume index (32±12 vs 25±10 mL/m2, P<0.001), left ventricle mass index (107±34 vs 93±25 g/m2, P=0.012), and left ventricle filling pressure (E/e'') (14±7 vs 12±5, P=0.012), whereas early diastolic mitral annular velocity (e') (5±2 vs 6±3 cm/s, P=0.021), late diastolic mitral annular velocity (A') (7±3 vs 9±2 cm/s, P<0.001), and peak systolic mitral annular velocity (7±2 vs 8±2 cm/s, P=0.045) were significantly lower. In multivariate Cox regression analysis detecting independent predictors of PaAF recurrence, lower A' (hazard ratio: 0.623, 95% confidence interval: 0.476-0.815, P=0.001) was a significant predictor of AF recurrence.

CONCLUSIONS

A', which indicates left atrial (LA) contractile function after sinus conversion, was the independent predictor of PaAF recurrence, whereas LA volume was not. LA function may be more important than LA volume in predicting recurrence particularly in patients with PaAF.

Left ventricular geometry, global function, and dyssynchrony in infants and children with pompe cardiomyopathy undergoing enzyme replacement therapy

BACKGROUND

Enzyme replacement therapy (ERT) for infantile-onset Pompe disease effectively reduces the left ventricular (LV) mass. This study sought to explore detailed process of LV reverse remodeling after ERT with the use of tissue Doppler and stain rate imaging.

METHODS AND RESULTS

Nine infants and children with Pompe cardiomyopathy undergoing ERT for ≥1 year, as well as 36 healthy control subjects, were studied. Global systolic and diastolic function was evaluated by peak systolic and early-diastolic velocity at mitral annulus. Temporal systolic and diastolic dyssynchrony was evaluated by the coefficient of variation of the time from the QRS complex to peak systolic and early-diastolic strain rate among 12 LV segments. All pre-ERT patients had impaired global systolic and diastolic function as well as increased regional dyssynchrony (P < .001 for each of all). During the regression of LV hypertrophy, all of these functional indices improved (P for trend <.001), with temporal diastolic dyssynchrony being a significant factor linking to LV mass index in multivariate analysis (P < .001).

CONCLUSIONS

ERT improved global LV function and dyssynchrony in Pompe patients. The relationship between LV mass and temporal diastolic dyssynchrony during reverse remodeling suggested a pathophysiologic role of dyssynchrony in Pompe cardiomyopathy.

Relation of gender and interatrial dyssynchrony on tissue Doppler imaging to the prediction of the progression to chronic atrial fibrillation in patients with nonvalvular paroxysmal atrial fibrillation

This prospective study aimed to identify the relation of gender and interatrial dyssynchrony on tissue Doppler imaging (TDI) to the prediction of the progression to chronic atrial fibrillation (CAF) in nonvalvular paroxysmal AF (PAF) patients. Nineteen consecutive men and 19 women with nonvalvular PAF were prospectively followed after echocardiography. We measured the interval of time from initiation of the P wave on the electrocardiogram until the beginning of the late diastolic TDI signal at the lateral border of the mitral (P-A'(M)) and the tricuspid annulus (P-A'(T)). Interatrial dyssynchrony was defined as the difference between the P-A'(M) and P-A'(T) intervals (A'(M)-A'(T)). The study endpoint was the onset of CAF (>6 months). Six men developed CAF during a follow-up of 32 +/- 26 months, and 3 women developed CAF during a follow-up of 25 +/- 19 months. Compared to those without CAF, the patients with CAF had significantly longer A'(M)- A'(T) intervals (men: 41 +/- 10 vs 27 +/- 12 ms, women: 64 +/- 4 vs 23 +/- 9 ms; P < 0.01) in both genders. Kaplan-Meier analysis, using cutoff values determined by analysis of receiver-operating characteristics curves, revealed that the progression to CAF was significantly observed more often when A'(M)-A'(T) interval was >34 ms in men and >43 ms in women. This prospective study suggests that nonvalvular PAF men and women with a high risk of developing CAF have "interatrial dyssynchrony" on atrial TDI, whose cutoff values are shorter and may affect the vulnerability of AF in men.

Hypertrophy pattern and regional myocardial mechanics are related in septal and apical hypertrophic cardiomyopathy

BACKGROUND

Hypertrophic cardiomyopathy (HCM) is associated with considerable phenotypic heterogeneity. Previous studies have shown a relationship between the degree and location of hypertrophy and the prognosis of patients. The aim of this study was to compare left ventricular (LV) circumferential and longitudinal regional mechanics in patients with septal HCM and apical HCM to study the relationship between hypertrophy and function as assessed by myocardial mechanics.

METHODS

Seventy-two patients with HCM (27 with apical HCM, 45 with septal HCM) were compared with 25 clinically normal and age-matched subjects. Myocardial mechanics were assessed using Velocity Vector Imaging, which extracts myocardial motion estimates from B-mode clips by tracking user-defined points and feature tracking. The Velocity Vector Imaging software generated data on global and regional systolic and diastolic longitudinal and circumferential strain, strain rate, and rotational angle velocities. One-way analysis of variance with post hoc multiple comparisons was used among the three groups.

RESULTS

Normal subjects had relatively uniform strain and strain rates for all LV segments. Compared with the normal group, patients with septal HCM had decreased LV regional longitudinal strain rates and strain at both the basal and mid septal and lateral segments (all P < .01). Compared with patients with apical HCM, those with septal HCM had higher LV circumferential strain rates and strain at the basal and mid segments (P < .05 to P < .01). There were significant differences in rotational velocities at the mid segments among the three groups (P < .05 to P < .001).

CONCLUSIONS

Patients with HCM have abnormalities in myocardial mechanics that are related to the site of abnormal myocardial hypertrophy.

Prediction of transition to chronic atrial fibrillation in elderly patients with nonvalvular paroxysmal atrial fibrillation by transthoracic Doppler echocardiography

BACKGROUND

It is well known that paroxysmal atrial fibrillation (PAF) often precedes the development of chronic atrial fibrillation (CAF).

HYPOTHESIS

The purpose of this study was to determine prospectively whether transthoracic echocardiography is useful for the prediction of the transition to CAF in elderly patients with nonvalvular PAF.

METHODS

Forty-two consecutive elderly patients (> or =65 years) with nonvalvular PAF were prospectively evaluated after undergoing transthoracic echocardiography. The study endpoint was the transition to CAF (AF; > or = 6 mo).

RESULTS

During a follow-up period of 32 +/- 24 mo, 12 patients developed CAF. Patients with CAF had a significantly lower peak A velocity (A) and a higher E/A ratio of the transmitral inflow (TMF) such as a pseudonormalization pattern, and a lower peak atrial reversal wave velocity, higher peak diastolic wave velocity (D), and lower peak systolic/diastolic wave velocity ratio (S/D ratio) of the pulmonary venous flow (PVF). Kaplan-Meier analysis revealed that the transition to CAF was observed more often when A was < or = 70 cm/sec and E/A ratio was > or = 1.07 of TMF, and D was > or = 44 cm/sec and the S/D ratio was < or = 1.34 of PVF. All patients developed CAF when the E/A ratio was > or = 1.15 or the S/D ratio was < or = 0.75.

CONCLUSIONS

This prospective study suggests that elderly patients at high risk for transition to CAF have a pseudonormalization pattern of TMF and a diastolic dominant pattern of PVF, and that transthoracic Doppler estimation of TMF and PVF may be useful in identifying elderly patients at high risk for the transition from nonvalvular PAF to CAF.

Therapeutic strategies for diastolic dysfunction: a clinical perspective

Diastolic dysfunction, which is increasingly viewed as being influential in precipitating heart failure and determining prognosis, is often unrecognized and has therapeutic implications distinct from those that occur with systolic dysfunction. In this review, several therapeutic modalities including pharmacologic, nonpharmacologic, and surgical approaches for primary diastolic dysfunction and heart failure will be discussed.

Impact of obstructive sleep apnea on left ventricular diastolic function

The aim of this study was to investigate the impact of obstructive sleep apnea (OSA) on left ventricular (LV) functional changes by using tissue Doppler imaging-derived indexes in patients with OSA. We studied 62 patients classified into 3 groups, namely 18 with mild to moderate OSA, 24 with severe OSA, and 20 control subjects without OSA according to the apnea-hypopnea index (AHI) on complete overnight polysomnogram. All underwent conventional and tissue Doppler echocardiographies. Only early diastolic velocity (Ea; -6.2 +/- 0.3 vs -7.1 +/- 0.3 vs -7.3 +/- 0.3 cm/s, respectively, for the 3 groups, p = 0.023) was significantly decreased in the severe OSA group. Other echocardiographic parameters of diastolic function such as isovolumic relaxation time, deceleration time, mitral inflow early/late wave velocity ratio, and pulmonary vein systolic/diastolic pulmonary vein velocity ratio were comparable among the 3 groups. AHI was correlated only with tissue Doppler imaging-derived indexes of LV diastolic function (Ea r = -0.382, p = 0.002; Ea/late diastolic velocity r = -0.329, p = 0.009), but not with conventional Doppler indexes. AHI remained a significant predictor of Ea after adjusting for age, heart rate, fasting glucose level, blood pressure, body mass index, and LV mass index in a multiple stepwise linear regression model (p = 0.007). In conclusion, only patients with severe OSA showed a greater impairment of LV diastolic function. Of all echocardiographic parameters of diastolic dysfunction investigated, only Ea was identified as the best index to demonstrate an association between LV diastolic dysfunction and severity of OSA independently of body mass index, diabetes mellitus, and hypertension.

Assessment of regional atrial function in patients with hypertrophic cardiomyopathies using tissue Doppler imaging

BACKGROUND

This study applied tissue Doppler imaging and color tissue Doppler imaging to study atrial function changes in patients with hypertrophic cardiomyopathy (HCM). The profile of the segmental atrial velocities and the strain rate were determined and compared with those of normal matched control subjects.

METHODS

This study investigated 20 patients with HCM and 20 age-matched healthy control subjects. In a four-chamber apical view, tissue Doppler imaging was used to measure the lateral left and right atrial (LA and RA) and interatrial septal (IAS) wall systolic, early, and late diastolic velocities. Similarly, the atrial strain rate during ventricular systole (SR(S)) and the early (SR(E)) and late (SR(A)) diastolic phases in patients and control subjects were measured. The interventricular septal tissue Doppler-derived isovolumic relaxation time was calculated.

RESULTS

Only the IAS annular and middle segments showed a significant reduction in the early diastolic velocity (mean, 4.01 +/- 2.2 vs 8.7 +/- 1.1, p = 0.001; 3.23 +/- 2 vs 6.01 +/- 1.9, p = 0.001, respectively) for the patients with HCM in comparison with the control subjects. Generally, the atrial strain rate was clearly reduced. The systolic strain rate (SR(S)) was significantly reduced in the LA wall in the annular (p = 0.007) and middle (p = 0.001) segments and in the IAS middle segment (p = 0.007). Similarly, there was a reduction of the early diastolic strain rate (SR(E)) in the LA annular (p = 0.001) and middle (p = 0.01) segments and in the IAS annular (p = 0.05) and middle (p = 0.001) segments, as well as in the RA annular segment (p = 0.02). The RA middle segments showed insignificant changes.

CONCLUSION

Atrial function may be affected by HCM due to impairment of myocardial diastolic function. Strain rate imaging is reproducible, yields readily obtained parameters that provide unique data about global and longitudinal segmental atrial contraction, and can quantify the atrial dysfunction in patients with HCM.

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).

Depressed Myocardial Contractile Reserve in Patients With Obstructive Sleep Apnea Assessed by Tissue Doppler Imaging With Dobutamine Stress Echocardiography

BACKGROUND

Hypoxia has been suggested to affect myocardial contractile function in patients with obstructive sleep apnea (OSA). We sought to determine whether myocardial contractile reserve (MCR), as evaluated by echocardiographic tissue Doppler imaging with dobutamine stress (TDDS), might be depressed in OSA patients.

METHODS

Thirty patients with suspected OSA (25 men and 5 women; mean age, 51 +/- 11 years [+/- SD]) underwent overnight polysomnography and TDDS. Peak myocardial systolic velocity (Sm) and peak myocardial early diastolic velocity (Em) in the 12 myocardial segments of the left ventricular (LV) walls were averaged, and the mean Sm and Em during TDDS were compared between patients with apnea-hypopnea index (AHI) <15/h (group 1, n = 13) and those with AHI >/= 15/h (group 2, n = 17). MCR was calculated as the difference between the resting and peak Sm during TDDS.

RESULTS

In both groups, Sm increased dose dependently during TDDS. However, the relative increase in Sm was significantly lower in group 2, resulting in a lower value of MCR (5.5 +/- 1.2 cm/s vs 7.4 +/- 1.3 cm/s, p < 0.001). The Em was lower in group 2 compared with group 1 throughout TDDS. MCR was correlated significantly with AHI (r = - 0.67, p < 0.0001), resting Em (r = 0.53, p < 0.005), and body mass index (r = - 0.46, p < 0.05) independent of the LV mass index.

CONCLUSIONS

OSA can affect MCR, implying an etiologic contribution from repetitive hypoxic events. TDDS could identify subtle abnormalities of OSA-related cardiac involvement.

No evidence for left ventricular diastolic dysfunction in asymptomatic normotensive type 2 diabetic patients: a case-control study with new echocardiographic techniques

OBJECTIVE

We sought to determine whether abnormalities of left ventricular structure and function could be detected in asymptomatic type 2 diabetic patients free of cardiovascular complications.

RESEARCH DESIGN AND METHODS

We compared 48 subjects with type 2 diabetes (34 men, 50+/-6 years) without hypertension, coronary artery disease and microangiopathic complications with 30 age-matched healthy controls. Left ventricular diastolic function was assessed by conventional Doppler echocardiography and new echocardiographic techniques (tissue Doppler imaging, color M-mode propagation velocity). A pseudonormal (PN) pattern of left ventricular filling was screened by several methods including Valsalva maneuver.

RESULTS

Systolic function was normal in all patients. There was no significant difference in conventional and new echocardiographic Doppler indices of diastolic function between patients and control subjects. A PN diastolic function frequently suggested by the Valsalva maneuver (20 patients) was excluded using the new parameters.

CONCLUSIONS

Diastolic dysfunction is not as frequent as previously described in selected patients with type 2 diabetes free of microangiopathic complications. New Doppler echocardiographic methods provide, in contrast with the Valsalva maneuver, a reliable estimate of diastolic function and should be incorporated in the non-invasive screening for diabetic cardiomyopathy.

Disturbed glucose metabolism is associated with left ventricular dysfunction using tissue Doppler imaging in patients with myocardial infarction

AIMS

To investigate the association between glucose abnormalities and left ventricular (LV) function assessed by tissue Doppler imaging (TDI) in patients with previous history of myocardial infarction and without known diabetes mellitus.

PATIENTS AND METHODS

In a cross-sectional study, 123 patients, aged 31-80 years, with a history of previous myocardial infarction and without known diabetes mellitus were examined with TDI echocardiography. A standard oral glucose test (OGTT) with 75 g of glucose was performed.

RESULTS

Two-hour plasma glucose were significantly and negatively associated with TDI parameters such as LV ejection time; early diastolic filling velocity (E'-v); ratio of the early to late diastolic filling velocity (E'/A') and positively associated with regional myocardial performance index (MPI) (P<0.05). Left ventricular ejection time and MPI were significantly higher; E'/A' and E'-v were significantly lower in patients with disturbed glucose metabolism compared with patients with normal glucose tolerance (P<0.01). These differences remain significant also when the patients with DM were excluded.

CONCLUSIONS

The present study demonstrates that disturbed glucose metabolism is associated with more pronounced LV dysfunction using TDI in patients with myocardial infarction. These abnormalities in LV function were more common not only in subjects with diabetes, but also in patients with prediabetic condition, impaired glucose intolerance.

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.

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.

Usefulness of Pulsed-Wave Tissue Doppler Echocardiography for the Assessment of the Left and Right Ventricular Function in Patients with Clinical Hypothyroidism

Clinical hypothyroidism (HT) is often associated with cardiovascular disorders, such as endothelial and myocardial dysfunction. Previous studies have explored left ventricular (LV) function using pulsed-wave tissue Doppler echocardiography (TDE) in HT. However, no study has utilized this technique in the assessment of right ventricular (RV) function in HT. Accordingly, we investigated the effects of clinical HT on LV and RV function by TDE. The study subjects included 35 newly diagnosed HT patients and 32 healthy normal controls. For each subject, serum FT3, FT4, TT3, TT4, and thyroid stimulating hormone (TSH) levels were measured, and standard echocardiography and TDE were performed. No statistically significant difference was found between patients and controls with regard to age, gender, body mass index, heart rate, and blood pressure. Compared to controls, TSH levels were significantly higher, and TT4 and FT4 levels were significantly lower. TDE showed that patients had significantly lower early diastolic tricuspid annular velocity (Ea) and early/late (Ea/Aa) diastolic tricuspid annular velocity ratio (P < 0.001 and P < 0.001, respectively), and significantly longer isovolumetric relaxation time (P < 0.001) than those of the controls. Aa, Sa, isovolumetric contraction time, and ejection time did not significantly differ. In addition, a significant relationship between some TDE indexes, and thyroid hormones (TT4 and FT4) and TSH was observed. We showed that patients with clinical HT are associated with impaired RV diastolic function, in addition to impaired LV diastolic function using TDE.

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.

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.

Echocardiographic findings in patients with Behçet's disease

Case-controlled studies have shown that the prevalence of left ventricular (LV) diastolic dysfunction is higher in patients with Behçet's disease. However, there are no data evaluating the value of Doppler tissue imaging (DTI) in Behçet's disease. The aim of this study was to evaluate the cardiac involvement and the LV function at rest and at the end of isometric exercise by pulse-wave Doppler and DTI methods in patients with Behçet's disease. Fifty-four patients with Behcet's disease and 50 control subjects were studied. Dimensions of cardiac chambers, aortic root dimension, valvular abnormalities, and systolic function were similar in both groups. The mean E/A ratio was significantly lower in patients than controls (1.22 +/- .09 vs 1.36 +/- 0.30, p = 0.01). The E/A ratio was <1 in 12 patients (22%) and in 3 controls (6%) (p = 0.02). By DTI, no difference was found in the mean S-, e-, and a-wave velocities, and e/a ratio between the 2 groups. The e/a ratio was <1 in 13 patients (24.1%) and in 7 controls (14%) (p = 0.2) by DTI. There were no differences in the mitral pulse-wave Doppler and DTI parameters in patient and control groups at the end of exercise. The prevalence of cardiac pathology in Behçet's disease did not differ appreciably from the controls. In conclusion, the LV systolic and diastolic functions in the patients with Behçet's disease and controls were similar not only at rest but also at the end of exercise.

Impaired coronary circulation in patients with apical hypertrophic cardiomyopathy: noninvasive analysis by transthoracic Doppler echocardiography

OBJECTIVES

We designed this study to examine the characteristics of coronary circulation in patients with apical hypertrophic cardiomyopathy (ApHCM) using noninvasive transthoracic Doppler echocardiography (TTDE).

BACKGROUND

Recent advances in TTDE have allowed noninvasive assessment of coronary circulation by the measurement of coronary flow velocity (CFV) patterns and coronary flow velocity reserve (CFVR). However, there have been no previous studies evaluating coronary circulation in ApHCM.

METHODS

We analyzed CFV and CFVR in the left anterior descending coronary artery (LAD), and apical wall thickness in the left ventricle, in 10 ApHCM subjects and 10 control subjects. Mean diastolic velocity (MDV) and time from the beginning of diastole to peak velocity (TPV), and CFVR, defined as a ratio of drug-induced hyperemic to basal MDV, were measured.

RESULTS

At baseline, MDV was higher, and TPV was longer, in ApHCM subjects than in control subjects (29 +/- 5.7 versus 19 +/- 6.5 cm/sec; p < 0.01 and 5.2 +/- 1.0 versus 3.5 +/- 0.6 msec; p < 0.005, respectively). CFVR in ApHCM subjects was significantly lower than in control subjects (1.9 +/- 0.4 versus 3.1 +/- 0.8; p < 0.005). CFVR and basal MDV in ApHCM subjects showed significant correlations with apical/posterior wall thickness ratio [CFVR; r =-0.84, p < 0.01 and MDV; r = 0.74, p < 0.05, respectively].

CONCLUSION

Noninvasive coronary flow assessment by TTDE revealed an impaired coronary circulation with reduced CFVR, high MDV at baseline and prolonged TPV. These results suggest that these characteristics of coronary circulation may provide an additional index for the assessment of ApHCM.

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.

Evaluation of right and left ventricular function using pulsed-wave tissue Doppler echocardiography in patients with subclinical hypothyroidism

Previous studies showed that subclinical hypothyroidism (SH) was associated with cardiovascular disorders, such as endothelial dysfunction, atherosclerosis and myocardial dysfunction. Only one study investigated left ventricular (LV) function using pulsed tissue Doppler echocardiography (TDE) in patients with SH. However, no study has used this technique in the identification of right ventricular (RV) function in these patients. We aimed to investigate the effect of SH on RV and LV function using TDE technique. The present study included 36 newly diagnosed SH patients and 28 healthy controls. For each subjects, serum free T3 (FT3), free T4 (FT4), total T3 (TT3), total T4 (TT4), TSH, peroxidase antibody (TPOab) and thyroglobulin antibody (TGab) levels were measured, and standard echocardiography and TDE were performed. In patients with SH, TSH levels were significantly higher, and TPOab and TGab levels were significantly higher when compared to healthy controls. TDE showed that the patients had significantly lower early diastolic mitral and tricuspid annular velocity (Ea) and early/late (Ea/Aa) diastolic mitral and tricuspid annular velocity ratio (p<0.05, p<0.05 and p<0.001, p<0.001, respectively), and significantly longer isovolumetric relaxation time (IRT) of left and right ventricles (p<0.001 and p<0.001, respectively). However, Aa, Sa, and isovolumetric contraction time (ICT) and ET (ejection time) of left and right ventricle did not significantly differ (p=ns for all). In addition, a negative correlation between TSH and TD-derived tricuspid Ea velocity and Ea/Aa ratio, and a positive correlation between TSH and IRT of right ventricle were observed. Our findings demonstrated that SH is associated with impaired RV diastolic function in addition to impaired LV diastolic function.

Association between Intraventricular Myocardial Systolic Dyssynchrony and Ventricular Arrhythmias in Patients with Hypertrophic Cardiomyopathy

BACKGROUND

The distribution and magnitude of left ventricular (LV) hypertrophy are not uniform in patients with hypertrophic cardiomyopathy (HCM), which results in regional heterogeneity of LV systolic and diastolic function. The aim of the study was to evaluate LV regional systolic asynchrony in patients with HCM by pulsed Doppler myocardial imaging (DMI).

METHODS

We studied 35 HCM patients and 45 age- and sex-matched controls. By the use of DMI, the following five different basal myocardial segments were measured: systolic peak velocity (Sm); early- and late-diastolic peak velocities; pre-contraction time (Q-Sm) (from the beginning of Q-wave of ECG to the onset of Sm); intraventricular systolic delay (IntraV-Del) (difference of Q-Sm in different LV myocardial segments); interventricular delay (InterV-Del) (difference of Q-Sm between the most delayed LV segment and right ventricular lateral wall).

RESULTS

DMI analysis showed in HCM lower myocardial systolic and early-diastolic peak velocities of all the analyzed segments. As for time intervals, controls showed homogeneous systolic activation of the ventricular walls. Conversely, HCM group, despite the absence of intraventricular conduction defects by surface ECG, showed significant both Inter- and IntraV-Del (P < 0.0001). Linear regression models pointed out independent positive associations of IntraV-Del with LV outflow gradient and septal wall thickness in HCM (P < 0.001). An IntraV-Del >30 msec well differentiated controls and HCM. In addition, an IntraV-Del > 45 msec (ROC curve) identified a subgroup of HCM patients with nonsustained ventricular tachycardia during Holter monitoring (90.9% sensitivity and 95.8% specificity).

CONCLUSIONS

The impairment of intrarventricular systolic synchronicity is strongly related to increased septal thickness and LV outflow-tract gradient in HCM. DMI analysis may be able to select subgroups of HCM patients at an increased risk of ventricular tachyarrhythmias.

Assessment of Left Ventricular Function Using Pulsed Tissue Doppler Imaging in Healthy Dogs and Dogs with Spontaneous Mitral Regurgitation

Pulsed tissue Doppler imaging (pulsed TDI) has been demonstrated to be useful for the estimation of left ventricular (LV) systolic and diastolic functions in various human cardiac diseases. The objectives of this study were to investigate the relationship between pulsed TDI and LV function by using cardiac catheterization in healthy dogs and to evaluate the clinical usefulness of pulsed TDI in dogs with spontaneous mitral regurgitation (MR). The peak early diastolic velocity (E'), peak atrial systolic velocity (A'), and peak systolic velocity (S') were detectable in the velocity profiles of the mitral annulus in all the dogs. In the healthy dogs, S' and E' were correlated with LV peak +dP/dt and -dP/dt, respectively. E' was lower in dogs with MR than in dogs without cardiac diseases. E/E' in the MR dogs with decompensated heart failure was significantly increased in comparison with those with compensated heart failure. The sensitivity and specificity of the E/E' cutoff value of 13.0 for identifying decompensated heart failure were 80% and 83%, respectively. In addition, E/E' was significantly correlated with the ratio of left atrial to aortic diameter. These findings suggest that canine pulsed TDI can be applied clinically for estimation of cardiac function and detection of cardiac decompensation and left atrial volume overload in dogs with MR.

Exercise capacity and cardiac function assessed by tissue Doppler imaging in chronic heart failure

OBJECTIVE

To examine the relation between longitudinal left ventricular function assessed by tissue Doppler imaging (TDi) and exercise capacity in heart failure.

SUBJECTS

153 patients with chronic heart failure from left ventricular systolic dysfunction (ejection fraction < 45%) and 87 age and sex matched controls.

METHODS

Echocardiography was used to measure conventional indices of left ventricular systolic function. TDi was used to assess left and right ventricular longitudinal function by measuring mitral and lateral tricuspid annular velocities during the cardiac cycle. Velocities measured at each point were the systolic peak (S(m)) and the diastolic troughs (E(m) and A(m)), corresponding to passive and active (atrial) left ventricular filling. Each patient also underwent treadmill exercise testing with metabolic gas exchange measurements.

RESULTS

Left and right ventricular TDi velocities were greater in controls than in patients. Left ventricular ejection fraction (LVEF) correlated with S(m) (r = 0.30, p = 0.0005), but not with E(m), A(m), or the E(m)/A(m) ratio. There were no significant differences between New York Heart Association (NYHA) functional class for any of the TDi variables. Right ventricular indices were not related to exercise capacity. Systolic myocardial motion measured by TDi correlated more closely with peak oxygen consumption (pVO2) (r = 0.35, p < 0.0001) than LVEF (r = 0.21, p < 0.02). The E(m)/A(m) ratio was not correlated with pVO2. In multiple regression, S(m) was the only left ventricular TDi variable to predict exercise capacity independently (p < 0.05).

CONCLUSIONS

Exercise capacity and symptoms are poorly related to conventional measures of cardiac function and more closely correlated with indices of longitudinal left ventricular function as assessed by TDi.

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.

Differences in regional systolic and diastolic function by Doppler tissue imaging in patients with hypertrophic cardiomyopathy and hypertrophy caused by hypertension

OBJECTIVE

Doppler tissue (DT) velocity abnormalities have been described in patients with pathologic left ventricular hypertrophy (LVH). Impaired myocardial function has been suggested as a primary disorder in hypertrophic cardiomyopathy (HCM) and differences in DT parameters have been reported to be distinguishable from other LVH causes. We evaluated DT differences for patients with LVH caused by hypertension and patients with HCM, assessing regional systolic and diastolic function.

METHODS

A total of 62 participants were studied: 21 with HCM; 22 with LVH secondary to hypertension; and 19 control subjects. DT was used to record mitral annulobasal segment motion in the longitudinal axis. Systolic and diastolic velocities were measured at lateral and septal sites, and well-known ratios were obtained for diastolic assessment. A new global function index (GFI) that evaluates both systole and diastole was also calculated (GFI = [Emi/E(DT)]/S(DT) [s x cm(-1)], where mi is mitral inflow, E is E wave, and S is systolic wave).

RESULTS

Comparison showed significant differences in all parameters evaluated at the septal-basal segment and a GFI value of 1.77 showed 85% sensitivity and 75% specificity for detecting HCM when interventricular septum thickness was increased.

CONCLUSIONS

In the presence of unexplained LVH, markedly decreased DT velocities at basal septum efficiently detect myocardial dysfunction at this segment, and a calculated GFI > 1.77 strongly supports the diagnosis of HCM.

Strain and strain rate imaging: a new clinical approach to quantifying regional myocardial function

On the basis of color Doppler myocardial motion data, 1-dimensional regional natural strain rate and strain curves can now be calculated by comparing local myocardial velocity profiles. Such deformation data sets may be an important, new, and more sensitive approach to quantifying both regional radial and long-axis function of the left or right ventricle in both acquired and congenital heart disease. The normal ranges of regional velocity, strain rate, and strain values have already been determined in both adults and children. This review will focus both on the potential clinical applications of these new ultrasound-based deformation parameters and the current limitations inherent in implementing the technique in everyday practice.

Characterization of Left Ventricular Diastolic Function by Tissue Doppler Imaging and Clinical Status in Children With Hypertrophic Cardiomyopathy

Background— Conventional transmitral Doppler indices are unreliable in assessing clinical status in patients with hypertrophic cardiomyopathy (HCM) because they are affected by loading conditions. This study sought to determine whether tissue Doppler velocities are predictive of adverse clinical outcomes including death, cardiac arrest, ventricular tachycardia (VT), significant cardiac symptoms, and exercise capacity in children with HCM.

Methods and Results— We studied 80 consecutive children (median age 12 years, median follow-up 26 months) evaluated at 1 hospital from January 1999 to August 2003 compared with 80 age- and gender-matched controls. Patients underwent echocardiography, ambulatory Holter monitoring, and upright exercise testing. Children with HCM had significantly decreased early diastolic tissue Doppler velocities at the lateral mitral (13.2 versus 19.3 cm/s), tricuspid (13.3 versus 16.3 cm/s), and septal (9.4 versus 13.5 cm/s) annuli compared with controls ( P <0.001 for each comparison). By forward stepwise regression analysis, early transmitral left ventricular filling velocity (E)/septal Ea ratio predicted death, cardiac arrest, or VT ( r =0.610, R 2 =0.37, P <0.001). Peak oxygen consumption (V̇ o 2 ) was most predictive of children who developed symptoms ( r =0.427, R 2 =0.182, P <0.001). Peak V̇ o 2 correlated inversely with E/Ea septal ratio ( r =−0.740, P <0.01).

Conclusions— Transmitral E/septal Ea ratio predicts children with HCM who are at risk of adverse clinical outcomes including death, cardiac arrest, VT, and significant cardiac symptoms. Peak V̇ o 2 correlated with peak exercise capacity in HCM patients.

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.