Differentials

Partial anomalous pulmonary venous drainage

SIGNS / SYMPTOMS
INVESTIGATIONS
SIGNS / SYMPTOMS

Signs and symptoms similar to interatrial communications

INVESTIGATIONS

Atrial septum intact with dilated right heart structures: identified by echocardiography in children, and MRI or CT in adults.

Ventricular septal defect

SIGNS / SYMPTOMS
INVESTIGATIONS
SIGNS / SYMPTOMS

Small ventricular septal defects (VSDs) are associated with a holosystolic murmur and normal first and second heart sounds. With a larger shunt volume (ratio of pulmonary vascular to systemic blood flow, Qp:Qs, >2), a mid-diastolic mitral valve flow murmur may be heard in addition to a holosystolic mid-frequency murmur.

INVESTIGATIONS

VSD identified by Doppler echocardiography.

Patent ductus arteriosus

SIGNS / SYMPTOMS
INVESTIGATIONS
SIGNS / SYMPTOMS

Associated with prematurity. Associated with bounding peripheral pulses due to wide pulse pressure. The left ventricular impulse may be prominent. The murmur associated with a patent ductus arteriosus (PDA) is often described as a machinery-like continuous murmur. However, in some premature and newborn infants the murmur can be heard only in systole. A mid-diastolic mitral valve flow murmur may be heard.

INVESTIGATIONS

PDA identified by Doppler echocardiography.

Pulmonary stenosis

SIGNS / SYMPTOMS
INVESTIGATIONS
SIGNS / SYMPTOMS

A click follows the first heart sound, which is best heard at the left upper sternal border.

The second heart sound may be normal, split, or single depending on the severity of the stenosis.

INVESTIGATIONS

Pulmonary stenosis identified by Doppler echocardiography.

Right bundle-branch block

SIGNS / SYMPTOMS
INVESTIGATIONS
SIGNS / SYMPTOMS

Can produce a widely split second heart sound similar to that heard in patients with an interatrial communication.

The characteristic murmurs are absent.

INVESTIGATIONS

ECG shows right bundle-branch block.

Echocardiography shows no evidence of an interatrial communication.

Other congenital heart defects

SIGNS / SYMPTOMS
INVESTIGATIONS
SIGNS / SYMPTOMS

Interatrial communications occur in the context of other congenital heart conditions, including transposition of the great arteries, pulmonary atresia, and Ebstein anomaly.

INVESTIGATIONS

Abnormal anatomy identified by Doppler echocardiography.

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