Dissection Type C – Case 3
- 77-year-old female who presented with chest pain and found to have a NSTEMI.
Past Medical History
- HTN, HLD, Former tobacco use, COPD, Lung cancer s/p XRT, Breast cancer s/p lumpectomy/XRT, hypothyroidism
- Echocardiography: Anterior and anterolateral wall hypokinesis, LVEF 40-45%.
- Home Medications: Amlodipine, Prednisone, Albuterol, Levothyroxine
- Adjunct Pharmacotherapy: Clopidogrel, Bivalirudin
- Underwent unsuccessful intervention of the LAD CTO.
- Aspiration thrombectomy was performed and this was followed by lesion preparation with serial balloon inflations.
- Procedure was complicated by a guide catheter (VL 3.5/6 Fr) induced, non-flow-limiting Type C dissection of the LM extending into the LCx.
- In addition, LM luminal narrowing was also present and due to the formation of a hematoma which was causing external compression of the vessel.
- LM dissection was treated with placement of a stent directly.
- Troponin-I peaked at 33.5 ng/mL and CK-MB peaked at 311 ng/mL.
- Patient was discharged home 4 days later without any sequelae.
- What is the likely explanation or reason why the complication occurred?
- Guide catheter induced injury of the LM while performing an intervention on a possible CTO lesion masquerading as a NSTEMI.
- How could the complication have been prevented?
- Maintain guide catheter coaxiality, be cautious with manipulation of the guide catheter, and continuously monitor the position of the guide catheter throughout the procedure. This is extremely important when there is difficulty delivering equipment in tortuous, calcified, long type C lesions.
- Consider using a different guide catheter (smaller size, smaller curve, different curve).
- Is there an alternate strategy that could have been used to manage the complication?
- Intracoronary imaging using IVUS should be considered in diagnosis of intramural hematoma and guidance of treatment strategy. IVUS is helpful in determining the optimal stent length, diameter, and landing zone.
- What are the important learning points?
- This is a Type C dissection because of the persistence of extraluminal contrast seen well after contrast injection.
- In patients who present with a NSTEMI the culprit vessel in rare cases can be a CTO.
- During CTO interventions, the guide catheter must be manipulated very cautiously to prevent injury. In these cases there is frequent wire exchanges and passage of equipment through the guide catheter which results in excess guide catheter movement which in can result in injury.
- In this case, the dissection led to the development of a hematoma. This occurred because the dissection had an entry point but no exit point. As the hematoma grew, it led to LM compression which resulted in a LM luminal narrowing but with preserved TIMI 3 flow.
- Generally, if a LM stent needs to be extended it is extended into the LAD. However, because the dissection extended into the LCx in this case, the stent was extended into the LCx and not the LAD.