Common Signs and Symptoms of Patent Ductus Arteriosus

The ductus arteriosus is a blood vessel that connects the aorta and the pulmonary artery during fetal development. This vessel plays a crucial role in directing blood flow to the lower part of the fetal body. Normally, after birth, the ductus arteriosus closes spontaneously. However, in some cases, it remains open—a condition known as patent ductus arteriosus (PDA). When this happens, blood flows from the high-pressure aorta to the lower-pressure pulmonary artery, essentially allowing the pulmonary circulation to "steal" blood from the systemic circulation.

Characteristic Heart Murmur

One of the most distinctive signs of PDA is a continuous heart murmur often described as sounding like a "machinery" murmur. This occurs because of the constant flow of blood through the open ductus arteriosus throughout the cardiac cycle. The murmur is typically heard best at the left upper sternal border and can be a key diagnostic clue during a physical examination.

Increased Pulmonary Blood Flow

Elevated Pulmonary Pressure

Due to the abnormal blood flow, there is an increase in blood volume in the pulmonary circulation. This can lead to pulmonary hypertension over time. Clinically, this may present as a loud and accentuated second heart sound (P2) in the pulmonary area, indicating elevated pressure in the pulmonary artery.

Peripheral Signs of Increased Pulse Pressure

The left-to-right shunting of blood also affects systemic circulation. As a result, patients may experience a decrease in diastolic blood pressure, leading to an increased pulse pressure. This can manifest in several peripheral signs, such as capillary pulsation—visible as a blanching and flushing of the skin with each heartbeat—and a "water-hammer" pulse. Additionally, a distinctive femoral "gunshot" sound may be heard when listening over the femoral artery, which is another hallmark of this condition.

Summary of Key Symptoms

In summary, the classic signs of patent ductus arteriosus include a continuous machinery-like heart murmur, signs of increased pulmonary blood flow, elevated pulmonary artery pressure, and peripheral indicators of widened pulse pressure such as capillary pulsation and femoral gunshot sounds. Recognizing these clinical features is essential for early diagnosis and timely management of PDA.