Successful Management of Iatrogenic Aortocoronary Dissection Induced by a Guide Extension Catheter Using Intravascular Ultrasound Guidance.

Iatrogenic aortocoronary dissection is an uncommon but potentially life‑threatening complication of percutaneous coronary intervention. We describe a case caused by a guide extension catheter, in which intravascular ultrasound (IVUS) enabled precise assessment and successful percutaneous management. A 79-year-old female with exertional chest pain underwent percutaneous coronary intervention after persistent symptoms despite optimal medical therapy. Severe, heavily calcified stenosis in the distal right coronary artery required balloon dilatation with a guide extension catheter. Following dilatation, a National Heart, Lung, and Blood Institute (NHLBI) type F dissection with contrast staining in the sinus of Valsalva was detected. The patient remained hemodynamically stable, and the guidewire was in the true lumen. IVUS identified the dissection entry point and extensive intramural hematoma. A drug‑eluting stent was deployed to seal the flap, restoring normal coronary flow. Post‑procedural coronary computed tomography confirmed that the dissection had not propagated into the ascending aorta and was completely sealed. Because the patient remained stable without ischemia or aortic regurgitation, conservative management was continued. Her recovery was uneventful, and follow‑up computed tomography at 10 months demonstrated complete healing. Although guide extension catheter-related aortocoronary dissection is rare, this case highlights the value of IVUS for defining the injury and guiding stent placement. Careful attention to catheter position and avoidance of automatic contrast injection are essential. Early recognition and prompt sealing of the entry site, followed by imaging to assess aortic involvement, are critical for optimal outcomes.