Multi-Modality Echocardiographic Techniques in Pathological Left Ventricular Hypertrophy Adults

Characteristics of the Multi-Modality Echocardiographic Techniques in Chinese Adults With Pathological Left Ventricular Hypertrophy - a Prospective, Multicenter, Clinical Study (MET-LVH Study)

This multicenter clinical study aims to evaluate the multi-modality echocardiographic parameters in patients with different pathological left ventricular hypertrophy (LVH) and investigate the correlation between echocardiographic parameters and different etiologies, providing an important theoretical basis for early identification and risk assessment in LVH patients.

Left ventricular hypertrophy (LVH) is an abnormal increase in the mass of the left ventricular myocardium, and its presence is associated with poor outcomes and ventricular arrhythmias. It is commonly seen in hypertension and aortic stenosis due to persistent pressure overload. In addition, it can also be found in genetic diseases and metabolic diseases, such as hypertrophic cardiomyopathy, cardiac amyloidosis and Fabry disease. Although patients with the latter type of LVH may often have normal loading conditions, there is significant heterogeneity in phenotypes and prognosis due to etiological variability. Hence for LVH patients, early identification of the underlying causes, effective intervention, follow up and surveillance may reduce mortality and improve survival. Echocardiography is the initial imaging modality for evaluation of cardiovascular diseases. And it plays an important role in the detection of LVH and potential causes in current clinical practice. Nevertheless, the feasibility of discriminatory for different diseases is limited by the fact that overlapping LVH in different conditions can often lead to diagnostic ambiguity. There is an urgent need to find echocardiographic parameters with high specificity to assist in the etiological diagnosis of patients with pathological LVH.

Patients with LVH commonly associate with left ventricular diastolic dysfunction, causing changes in the structure and function of the left atrium prior to abnormal left ventricular ejection fraction. Left atrium function at reservoir, conduit and booster phases can be noninvasively quantify by speckle tracking echocardiography. However, there is incomplete information on left atrium strain characteristics in patients with LV pathological hypertrophy. The myocardial longitudinal strain parameters derived from speckle tracking echocardiography is a sensitive noninvasive method of assessing left ventricular myocardial performance. The relative "apical sparing" can be easily visualized for patients with cardiac amyloidosis. The reduced longitudinal strain in the basal lateral wall could be found at the very early stages of Fabry disease. Hence the specific manifestations derived from longitudinal strain mapping can assist in the differentiate patients from various causes of LVH. And left ventricular volume and mass index assessed by three-dimension echocardiography are independently associated with adverse outcomes of LVH patients. Therefore, appropriate utilization of multi-modality echocardiography techniques is fundamental to accurate diagnosis as well as longitudinal care of pathological LVH patients. However, a great deal of studies were based on small samples and single center. There is lack of defined diagnostic results based on multi-modality echocardiography and comprehensive markers derived from large-scale study.

In this study, we expected to provide a set of parameters for different etiology by including patients with different pathological LVH based on multi-modality echocardiography, so as to assisting in early identification and risk assessment in LVH patients.

Inclusion Criteria:

• Age ≥ 18 years old;
• A wall thickness ≥ 12mm in one or more LV myocardial segments as measured by 2D echocardiography.
• Patients with definite diagnosis of hypertensive heart disease, hypertrophic cardiomyopathy, cardiac amyloidosis or Fabry disease.

Exclusion Criteria:

• Patients with severe valvular disease, congenital heart disease, aortic coarctation, multiple Takayasu arteritis, or other cardiovascular diseases that may cause ventricular hypertrophy;
• Hypertrophy of myocardium caused by high intensity exercise;
• Poor ultrasonic image quality, which cannot meet analysis requirement.