Dissection Type B – Case 2
- 36-year-old female who presented with a NSTEMI.
Past Medical History
- Echocardiography: Anterior wall hypokinesis, LVEF 45-50%.
- Home Medications: None
- Adjunct Pharmacotherapy: Clopidogrel, Bivalirudin
- Underwent cardiac catheterization with procedure being complicated by diagnostic catheter induced, non-flow limiting Type B dissection of the LM.
- PCI of the mid LAD was performed followed by direct stenting of the LM.
- Follow up angiography after LM stent placed revealed AVC of the mid LAD, distal to the recently placed stent.
- A microcatheter was used to deliver IC vasodilators, without improvement in coronary flow. Therefore, AVC was thought to due to a distal stent edge Type F dissection.
- A direct stent was placed with overlap into the previously placed stent in the mid LAD.
- This was followed by post dilatation of the LM stent.
- Final angiogram revealed successful treatment of the LM dissection and Type F dissection with restoration of TIMI 3 flow in the LAD.
- Troponin-I peaked at 5.5 ng/mL and CK-MB peaked at 24.4 ng/mL.
- Patient was discharged the next day without any sequelae.
- What is the likely explanation or reason why the complication occurred?
- Type B dissection of the LM caused by injury from the diagnostic catheter.
- Type F dissection involving the distal stent edge within the mid LAD is likely due to placement of a stent in a vessel which is predisposed for dissection, as the patient probably has undiagnosed SCAD.
- How could the complication have been prevented?
- A young female patient who presents with ACS, the possibility of SCAD should have been considered upfront.
- Maintain guide catheter co-axiality, 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.
- Is there an alternate strategy that could have been used to manage the complication?
- PCI of the LM dissection along with medical management of residual mid LAD disease would have been a reasonable approach because the patient has likely undiagnosed Type 2 SCAD.
- Consider using an imaging-based approach in the treatment of the dissection and AVC.
- What are the important learning points?
- This is a Type B dissection of the LM because of the presence of a parallel tract.
- This is a Type F dissection of the mid LAD distal to the stent.
- When you have AVC the differential includes spasm, thrombus with distal embolization, and dissection.
- In this case, spasm was ruled out with administration of IC vasodilators, as no improvement in flow was seen.
- We used bivalirudin and per institution policy, we do not engage the coronary artery with the guide catheter until ACT is >200, and do not introduce coronary equipment until the ACT is >300. Therefore, the likelihood of an intracoronary thrombus formation is low with adequate anticoagulation and antiplatelet therapy.
- Maintaining wire position is extremely important, especially when dealing with complex interventions. Be cautious to avoid loss of wire position and possible wire entrapment.
- Intravascular imaging of the coronaries with IVUS is helpful in the diagnosis and confirmation of SCAD, and in determining the etiology of AVC.
- Young female patients who present with ACS, SCAD must be highly considered in the differential diagnosis. In patients with SCAD, intervention should be performed if they have electrical instability, hemodynamic instability, or ongoing ischemia, otherwise medical management is preferred.