Phasic venous return abnormality in chronic pulmonary diseases: pulsed Doppler echocardiography study

Area of Science:

• Cardiology
• Pulmonology
• Medical Imaging

Background:

• Venous return is crucial for cardiac function.
• Chronic pulmonary diseases can significantly impact hemodynamics.
• Understanding venous return alterations is vital for managing these conditions.

Purpose of the Study:

• To investigate the characteristics of venous return in patients with chronic pulmonary diseases.
• To identify factors influencing these venous return features.
• To correlate venous flow patterns with lung function and pulmonary vascular resistance.

Main Methods:

• Analysis of respiration-related variation in superior vena cava (SVC) flow using pulsed Doppler echocardiography.
• Comparison of flow patterns between 85 patients with chronic pulmonary diseases and 54 healthy controls.
• Assessment of forced expiratory volume in 1 second (FEV1.0%) and vital capacity (VC).

Main Results:

• Healthy subjects exhibited a typical "type I" SVC flow pattern.
• Patients with pulmonary diseases showed "type I" or an abnormal "type II" pattern (wave disappearance).
• Type II pattern was more frequent in patients with reduced FEV1.0% and %VC, linked to elevated right atrial pressure and positive pleural pressure.
• Increased A wave velocity correlated with pulmonary vascular resistance.

Conclusions:

• Venous return in chronic pulmonary disease is influenced by ventilatory disturbances and pulmonary vascular resistance.
• Abnormal SVC flow patterns (type II) are associated with decreased lung function and elevated right atrial pressure.
• Echocardiography can reveal significant alterations in venous return dynamics in pulmonary disease.