During a transeptal procedure, the right heart catheter travels from the RA to the LA via which structure?

During a transeptal procedure, the right heart catheter travels from the RA to the LA via which structure?

• A. the interatrial septum
• B. the tricuspid valve
• C. the mitral valve
• D. the aortic valve

Answer: (A)

Crossing from the right atrium to the left atrium requires going through the interatrial septum, the wall that separates the two atria. In a transeptal procedure, a needle and sheath are directed to the thin region of the septum—usually the fossa ovalis—and are used to puncture this septum, allowing the catheter to enter the left atrium. This route is chosen specifically to access the left atrium for procedures such as left-sided ablations or mitral interventions. The other structures listed lie between different chambers: the tricuspid valve sits between the right atrium and right ventricle; the mitral valve sits between the left atrium and left ventricle; the aortic valve sits between the left ventricle and the aorta.

Crossing from the right atrium to the left atrium requires going through the interatrial septum, the wall that separates the two atria. In a transeptal procedure, a needle and sheath are directed to the thin region of the septum—usually the fossa ovalis—and are used to puncture this septum, allowing the catheter to enter the left atrium. This route is chosen specifically to access the left atrium for procedures such as left-sided ablations or mitral interventions.

The other structures listed lie between different chambers: the tricuspid valve sits between the right atrium and right ventricle; the mitral valve sits between the left atrium and left ventricle; the aortic valve sits between the left ventricle and the aorta.