Judkins right coronary catheter has a sharp primary curve and a shallow secondary curve. The primary curve engages the right coronary ostium while the secondary curve engages the opposite wall of the aorta. The tip usually tapers to 5F size, irrespective of the nominal diameter of the catheter. Short form for Judkins right catheter is JR.
Judkins right coronary catheter is used primarily to engage the right coronary artery for coronary angiography. Very often it is used to enter the left subclavian artery to get an angio of the left internal mammary artery. It is also used to do renal angiography as it is easy to enter the renal arteries with JR catheter. JR catheter can be used both by the femoral access and the radial access.
JR guide catheter is also available, which is used for coronary angioplasty. It has a thicker wall and a wider lumen to accommodate hardwares like guidewires, balloon catheters, stents and Doppler wires.
Curve lengthof the catheter is the distance between the primary curve and the secondary curve. If it is 4 cm, it is called as JR4 catheter. Dilated aorta requires a longer curve length while a non dilated one requires a shorter curve length.