Genetically determined pattern of left ventricular function in normal and hypertensive hearts.

Area of Science:

• Cardiology
• Genetics
• Biophysics

Background:

• Left ventricular (LV) function assessment is crucial for cardiovascular health.
• Understanding the genetic and environmental influences on cardiac function is key to identifying disease predispositions.
• Hypertension's impact on genetically determined cardiac function requires further elucidation.

Purpose of the Study:

• To evaluate the heritability of left ventricular systolic and diastolic function using speckle-tracking echocardiography.
• To investigate whether hypertension modifies the genetically determined patterns of cardiac contraction.
• To explore the genetic basis of preserved systolic function despite early hypertensive heart disease.

Main Methods:

• Recruited 92 Caucasian twin pairs for echocardiographic assessment.
• Utilized speckle-tracking echocardiography, including global longitudinal strain (GLS) analysis.
• Analyzed heritability of systolic (ejection fraction, GLS) and diastolic function parameters.

Main Results:

• Global longitudinal strain (GLS) demonstrated dominant heritability (75%), higher than ejection fraction (61%).
• Heritability of GLS remained consistent between hypertensive and non-hypertensive subjects.
• Diastolic function parameters, such as early diastolic strain rate, exhibited low heritability.

Conclusions:

• LV systolic biomechanics, especially GLS, is strongly heritable, indicating a significant genetic component.
• A genetic framework appears to preserve systolic function, even in early hypertension.
• Diastolic dysfunction may be more influenced by environmental factors than systolic function.