Immediate bail-out TAP-stenting for the treatment of iatrogenic aortocoronary dissection involving left main bifurcation.

Iatrogenic aortocoronary dissection is a rare but potentially disastrous complication of percutaneous coronary intervention. The left main dissection extending into distal bifurcation involving both the left anterior descending and left circumflex is a complex and vital complication, which is classified as Eshtehardi Type II dissection. We presented a case of iatrogenic left main coronary artery dissection with upcoming closure of both major branches, which was successfully managed by immediate bail-out TAP-stenting. The 77-year-old patient was discharged without any complication, and 1-year follow-up indicated stent patency and favorable clinical result. Immediate bail-out stenting is a feasible and reasonable initial management for this lethal complication.

Introduction

Iatrogenic aortocoronary dissection is a rare but potentially disastrous complication of percutaneous coronary intervention (PCI). This is one of the important causes for procedure failure associated with the risk of myocardial infarction and death, where the incidence has been reported about 0.1% in previous studies.[1] The rapid development of antegrade and/or retrograde dissection flap not only causes acute closure of the coronary artery, but also brings about aortic regurgitation, haemopericardium or even abdominal aorta dissection in severe cases.[2],[3]

The left main (LM) dissection extending into distal bifurcation involving both the left anterior descending (LAD) and left circumflex (LCX) is a complex and vital complication, which is classified as Eshtehardi Type II dissection.[4] We presented a case of iatrogenic LM dissection with upcoming closure of both major branches, which was successfully managed by immediate bail-out TAP-stenting (T-Stenting and Small Protrusion Technique).

Case report

A 77-year-old female had been suffering from ischemia-related chest pain for 6 years. She had a history of hypertension. Her cardiac, renal, liver functions were normal. Transradial coronary angiography revealed severe lesions in proximal LAD and mid LCX (Figure 1A, 1B). There was no critical stenosis in the LM and right coronary artery. A sirolimus-eluting stent (2.5/28 mm, CypherSelect, Cordis) was successfully implanted in LCX. When performed pre-dilation in mid LAD by semi-compliant balloon (2.5/15 mm, Voyager, Abbott), a retrograde dissection extended from mid LAD to LM and aorta (Figure 1C, white arrows). Despite obliteration of the LM-LAD dissection with two stents (2.75/33 mm in LAD, 3.5/33 mm in LM, CypherSelect, Cordis), retrograde extension of LCX dissection was present on subsequent angiographic view (Figure 1D, white arrow). Thereafter, we performed TAP-stenting in the LM bifurcation (2.75/33mm in LCX, CypherSelect, Cordis) by transradial approach (Figure 1E, 1F). Fortunately, the vital signs remained stable during the 15 minutes rescue. The patient was discharged without any complication, and 1-year follow-up indicated stent patency and favorable clinical result (Figure 1G, 1H).

Figure 1.

Coronary angiography of iatrogenic aortocoronary dissection.

(A&B): Transradial coronary angiography revealed severe lesions in proximal LAD and mid LCX. (C): A sirolimus-eluting stent (2.5/28 mm, CypherSelect, Cordis) was successfully implanted in LCX. When we performed pre-dilation in mid LAD by semi-compliant balloon (2.5/15 mm, Voyager, Abbott), a retrograde dissection extended from mid LAD to LM and aorta (white arrow). (D): Despite obliteration of the LM-LAD dissection with two stents (2.75/33mm in LAD, 3.5/33mm in LM, CypherSelect, Cordis), retrograde extension of LCX dissection was present on subsequent angiographic view (white arrow). (E&F): We performed TAP-stenting (T-Stenting and Small Protrusion Technique) in the LM bifurcation by transradial approach (2.75/33mm in LCX, CypherSelect, Cordis). Fortunately, the vital sign remained stable during the 15 minutes rescue. (G&H): The 77-year-old patient was discharged without any complication, and 1-year follow-up indicated stent patency and favorable clinical result. LAD: left anterior descending; LCX: left circumflex; LM: left main.

Discussion

Iatrogenic aortocoronary dissection is a vital complication of PCI. Although emergency surgical repair is generally the first-choice therapeutic strategy, when taking full anticoagulation and antiplatelet settings into consideration, as well as the unstable hemodynamic condition, surgery may be more risky in this circumstance.[5] Actually, sealing the entry site of dissection immediately by stent prevents the rapid development of hematoma. Hence, operators should immediately make every effort to prevent progression of dissection.

Some lessons from this case include: (1) It is crucial to maintain entire system stability to manage the complication based on the initial guiding catheter and wire. When aortocoronary dissection occurs, total occlusion may happen unexpectedly in a few minutes. If the operator decides to change access (radial to femoral), or the size of guiding catheter (6F to 7F or even 8F), the guide wire will cross the dissection again. It is imaginable that the guide wire may enter a false lumen so as to prolong the operation time, and than dissection deteriorates. (2) Since the most important vessel should be kept patent first, single-stent strategy is the first-choice when taking 6F transradial access into account. Under emergency of LM bifurcation dissection, the operator should choose a simple stenting technique to reduce difficulty and complexity of management. Actually, it is difficult to thread the stent strut under emergency conditions, so bifurcation stenting can be left for senior operator. (3) Only if procedure could be finished in short order and then the risk would be reduced. Try to identify and seal the entry port with a long stent at once, and stop blood flow in the false lumen to avoid the distribution of dissection before hemodynamic collapse. While blood flow is still poor after stenting, consider intravascular ultrasound to determine whether the stent covers entry port, and whether flow limitation is due to thrombus or intramural hematoma, in order to manage more or less aggressive anticoagulation. Moreover, we should keep in mind that circulatory support is not mandatory or even contraindicated. It is the fact that the extension of dissection and hematoma lead to acute closure of vessel. Theoretically, even if hemodynamic collapse occurred, intra-aortic balloon pump should not be implanted because it can only delay stent deployment, and exacerbate both of the antegrade and retrograde dissection. (4) The operator should save the patient by himself, and hardly count on surgeons. When coronary sinus dissection is detected, deployment of an additional stent that protruded into the aorta helps to prevent acute artery occlusion due to torn flap of aorta. If bifurcation stenting is unavoidable, the TAP-stenting technique is relatively simple, which is proved to allow full coverage of bifurcation lesions and facilitate final kissing balloon.[6]

This report presented a case of iatrogenic LM bifurcation dissection with upcoming closure of LAD and LCX, which was successfully managed by immediate bail-out TAP-stenting. From the above, we introduce the “4S” law for treatment in this report, which is “stable, smart, swift and stent”. The “4S” law based on immediate bail-out stenting is a feasible and reasonable initial management for this lethal complication.