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Heart rate changes during the Valsalva maneuver in patients with isolated aortic insufficiency
A E Navarro1, D F Dávila, A Torres
1Centro de Investigaciones Cardiovasculares, Universidad de Los Andes, Merida, Venezuela.
Insights
In patients with aortic insufficiency, left ventricular dilatation did not correlate with impaired heart rate control during the Valsalva maneuver. Parasympathetic heart rate control remained normal despite enlarged left ventricles.
Area of Science:
- Cardiology
- Physiology
Background:
- Chronic aortic insufficiency can lead to left ventricular dilatation.
- Assessing autonomic nervous system function is crucial in cardiovascular disease management.
Purpose of the Study:
- To investigate the relationship between left ventricular dilatation and parasympathetic heart rate control, measured by the Valsalva ratio, in asymptomatic patients with chronic aortic insufficiency.
Main Methods:
- Studied 9 asymptomatic patients with isolated chronic aortic insufficiency.
- Assessed left ventricular function and dimensions using two-dimensional echocardiography and cardiac catheterization.
- Evaluated heart rate changes during the Valsalva maneuver to calculate the Valsalva ratio.
Main Results:
- All patients exhibited significantly increased left ventricular internal diameters and volumes.
- Left ventricular ejection fraction was normal or only slightly depressed (EF > 0.40).
- No significant correlation was found between the Valsalva ratio and left ventricular volumes or ejection fraction.
Conclusions:
- Asymptomatic patients with left ventricular dilatation and preserved ejection fraction demonstrated normal parasympathetic heart rate control (Valsalva ratio).
- Left ventricular dilatation alone may not be the primary cause of abnormal parasympathetic control in acquired heart disease.
- Further research is needed to identify mechanisms underlying autonomic dysfunction in these patients.
Abstract:
To determine the possible relationship between left ventricular dilatation and heart rate changes provoked by the Valsalva maneuver (Valsalva ratio), we studied 9 patients with isolated chronic aortic insufficiency. Left ventricular systolic function was assessed by two-dimensional echocardiography and cardiac catheterization. All patients were asymptomatic (functional class I of the New York Heart Association). The left ventricular internal diameters and volumes were significantly increased in all patients. The asymptomatic patients had either normal or slightly depressed ejection fraction (EF > 0.40). The Valsalva ratio of these asymptomatic patients showed no significant correlation with the left ventricular volumes or with the left ventricular ejection fraction. In other words, parasympathetic heart rate control, as expressed by the Valsalva ratio, was normal in the asymptomatic patients with left ventricular dilatation and preserved left ventricular ejection fraction. Therefore, left ventricular dilatation may not be the major mechanism responsible for the abnormal parasympathetic heart rate control of patients with acquired heart disease.