Subclinical left ventricular dysfunction in systemic hypertension and the role of 24-hour blood pressure

Area of Science:

• Cardiology
• Hypertension Research
• Echocardiography

Background:

• The relationship between blood pressure (BP) and left ventricular (LV) systolic function in systemic hypertension remains debated.
• Assessing LV systolic function accurately is crucial for understanding hypertensive heart disease progression.

Purpose of the Study:

• To investigate the association between 24-hour BP and LV systolic function, specifically using midwall fractional shortening (FS).
• To determine if midwall FS is a more sensitive marker for detecting depressed cardiac function in never-treated hypertensive individuals compared to endocardial FS.

Main Methods:

• Echocardiography and 24-hour ambulatory BP monitoring were performed on 1,702 never-treated hypertensive subjects.
• LV midwall fractional shortening (FS) was calculated, accounting for epicardial migration during systole.
• Depressed LV function was defined as FS below the fifth percentile of predicted values based on healthy normotensives.

Main Results:

• Using midwall FS increased the detection of depressed LV function from 3.5% to 17.5% in hypertensive patients.
• Subjects with low midwall LV function exhibited similar office systolic BP but significantly higher 24-hour systolic BP compared to those with normal function.
• Midwall FS showed a stronger inverse correlation with 24-hour systolic BP and LV mass than endocardial FS.

Conclusions:

• Increased 24-hour BP load is associated with chronically depressed myocardial function in systemic hypertension, even without overt heart disease.
• Midwall FS is a more sensitive indicator of subclinical cardiac dysfunction in hypertensive individuals than endocardial FS.
• These findings highlight the importance of 24-hour BP monitoring for assessing cardiovascular risk in hypertension.