Impaired left ventricular function during exercise in hypertensive patients with normal coronary arteriograms

Area of Science:

• Cardiology
• Internal Medicine
• Physiology

Background:

• Left ventricular hypertrophy (LVH) is often associated with myocardial ischemia.
• Hypertensive individuals with LVH and normal coronary arteriograms can present with exercise-induced angina and ST-segment depression.

Purpose of the Study:

• To compare left ventricular function during rest and exercise in hypertensive patients with LVH and normal coronary arteries versus those with coronary artery disease (CAD).
• To investigate the impact of ischemia on cardiac function in hypertensive patients without obstructive coronary artery disease.

Main Methods:

• Heart catheterization was used to assess left ventricular function at rest and during exercise (50 W and 75 W).
• Pulmonary wedge pressure and cardiac output were measured in 17 hypertensive patients with LVH and normal coronary arteriograms (Group 1) and compared to 17 hypertensive patients with CAD (Group 2).
• Exercise electrocardiogram (ECG) and Holter ECG were utilized.

Main Results:

• Both groups showed a pathological increase in pulmonary wedge pressure at low work loads (50 W and 75 W), with no significant difference between them.
• Cardiac output remained normal in both groups.
• No significant correlation was found between ST-segment depression, pulmonary wedge pressure, LVH, and Holter ECG findings.

Conclusions:

• Hypertensive patients without coronary artery disease but with LVH can exhibit disturbed cardiac pump function due to ischemia at low work loads.
• This ischemic dysfunction in hypertensive patients without CAD is comparable to that observed in patients with CAD.
• Such findings may contribute to subendocardial fibrosis and the subsequent development of heart failure.