FMGE 2023 — Surgery

Q: Which is the least commonly used graft for coronary artery bypass graft (CABG)?

Intercostal artery. ***Intercostal artery***- This artery is **rarely used** in CABG due to its small caliber, difficult harvesting, and high risk of **graft spasm**.- Its use is generally restricted to highly unusual circumstances or when all major **arterial** and **venous conduits** are unavailable. *Long saphenous vein*- The **long saphenous vein (LSV)** is the most common venous graft and is frequently used, particularly for targets other than the LAD.- Though easily accessible and long, LSV grafts have significantly lower long-term patency rates compared to arterial grafts due to susceptibility to **intimal hyperplasia** and atherosclerosis. *Internal mammary artery* - The **Internal Mammary Artery (IMA)** (or Internal Thoracic Artery) is universally considered the **gold standard** graft, particularly for the Left Anterior Descending (LAD) artery.- It offers the highest long-term patency (often >90% at 10 years), making it the most commonly preferred graft, not the least common. *Radial artery*- The **radial artery (RA)** is widely used as a second arterial conduit, offering excellent long-term patency rates superior to vein grafts but slightly less than the IMA.- Preoperative evaluation using the **Allen's test** is necessary to confirm adequate collateral circulation via the ulnar artery before harvesting.

Q: Which of the following is the recommended treatment for the ureteric stone shown in the image?

Ureteroscopy. ***Ureteroscopy*** - This procedure involves passing a small, flexible scope through the urethra and bladder into the ureter to directly visualize and treat the stone. - It is a highly effective and preferred treatment for stones located in the **mid and distal ureter**, allowing for either retrieval with a basket or fragmentation with a laser. *Percutaneous nephrolithotomy* - This is an invasive procedure where an instrument is passed directly into the kidney through a small incision in the back. - It is primarily indicated for the removal of **large renal stones** (typically >2 cm) or staghorn calculi located within the kidney, not for ureteric stones. *ESWL* - Extracorporeal Shock Wave Lithotripsy (ESWL) uses focused **shock waves** from outside the body to break the stone into smaller fragments that can be passed in the urine. - While an option for some ureteric and kidney stones, its success rate is lower for stones in the **lower ureter** and for harder stones, making ureteroscopy often more effective. *Wait and watch* - This approach, often combined with **Medical Expulsive Therapy** (e.g., alpha-blockers), is reserved for small, uncomplicated stones (typically **<5 mm**) that are likely to pass spontaneously. - It is not recommended for larger stones, stones causing significant obstruction or severe symptoms, or those that fail to pass after a trial period.

22 Questions — Page 3 of 3

Q21

Which is the least commonly used graft for coronary artery bypass graft (CABG)?

Q22

Which of the following is the recommended treatment for the ureteric stone shown in the image?