Serial Changes in Pulmonary Hemodynamics During Pregnancy: A Non-Invasive Study Using Doppler Echocardiography

This study aimed to describe the pulmonary hemodynamic changes during the course of pregnancy and to observe any significant effects on symptomatology and outcome of pregnancy due to these changes.

A total of 75 patients were recruited for the study, 60 pregnant women from first trimester to third trimester and 6 weeks of puerperium for the study group and 15 non-pregnant patients. All the subjects were interrogated about their complaints like excessive cough, exertional dyspnea, palpitations, orthopnea, syncope, exertional chest pain and lower extremity edema along with their duration. Baseline investigations, echocardiography (ECG) and Doppler echo were done.

The commonest symptoms were palpitations (40%), exertional dyspnea (35%) and lower extremity edema (47%). Palpitations and dyspnea were also present in control group. Right axis deviation was the next most common abnormality in study group (12.3% patients). Pulmonary blood flow was decreased by more than 50% of predelivery value at the end of puerperium. Fall in pulmonary vascular resistance returned to base line values. Increased pulmonary artery pressure was seen during the pregnancy, which was not statistically significant.

During pregnancy, though the pulmonary blood flow increases significantly, the pulmonary artery pressure remains unchanged due to substantial fall in pulmonary vascular resistance in early gestation.