[TA] one of the arteries supplying the anterior portions of the intercostal spaces of the thoracic wall. Anterior intercostal arteries 1-6 arise as branches of the internal thoracic artery; 7-11 arise as branches of the musculophrenic artery. SYN: rami intercostales anteriores arteriae thoracicae internae [TA], anterior intercostal arteries, rami intercostales anteriores.