A 64-year-old gentleman with a history of diabetes, hypertension, hyperlipidemia presented to the emergency department with chest pain and dyspnea. Although initially hemodynamically stable with adequate oxygenation on 2L/min oxygen supplement, he soon developed desaturation and cardiogenic shock, requiring intubation with mechanical ventilation and inotropic support.

Chest X ray: pulmonary edemaElectrocardiogram: sinus rhythm, ST elevation over leads aVR and V1, ST depression over leads I,II, V4-6Echocardiogram: left ventricular ejection fraction (LVEF) 28% with global hypokinesia of the left ventricleHigh sensitivity Troponin I: 3345 ng/LLactate: 2.8 mmol/LArterial blood gas: pH 7.34, bicarbonate 18.9 mmol/L, base excess -6 mmol/L

Coronary angiography via right femoral approach with JL4 JR4 6Fr diagnostic cathetersLeft main (LM): critical stenosis with pressure damping on engagement, bifurcation lesion (Medina 1,1,1)Left anterior descending artery (LAD): o-mLAD 90% stenosis, D1 90% stenosisLeft circumflex artery (LCX): o-pLCx 90% stenosisRight coronary artery (RCA): pRCA chronic total occlusion (CTO)

Impella CP was first placed for hemodynamic support. LM was engaged with JL 3.5 7Fr. dLCX and dLAD were then wired. LM-LCX was dilated with NC TREK 2.0/15 and NC Sapphire 3.0/15. o-mLCX was stented with Xience 2.0/33 and 2.75/23. The oLCX stent was then crushed with NC Sapphire 3.0/15. LM-oLAD was stented with Xience 3.5/23 and post-dilated with NC TREK 4.0/12. pLAD was pre-dilated with NC TREK 2.5/15 and NC Sapphire 2.75/12. The first diagonal branch (D1) was then wired, and pre-dilated with Sapphire 1.5/15 and NC Sapphire 2.0/15, then stented with Coroflex 2.0/16. pLAD was further pre-dilated and D1 stent crushed with Raiden 2.5/15 and Raiden 3.0/10. Then pLAD was again pre-dilated with NC TREK 3.5/15. p-mLAD was stented with Xience 2.5/38. Intravascular Ultrasound (IVUS) to LAD revealed stent under-expansion. LAD stents were then post-dilated with Raiden 3.0/10 and Raiden 3.5/10. LCX was rewired and stent strut opened with Zinrai 1.5/15. LCX stent was post-dilated with NC TREK 2.25/12, NC Sapphire 2.75/12 and Raiden 3.0/10. LAD/LCX kissing balloons were performed with NC TREK 3.5/15 and 3.0/15. LM proximal optimization technique (POT) was done with NC Pantera Leo 4.0/8. We then attempted to rewire D1 but unsuccessfully. We decided for staged percutaneous coronary intervention (PCI) to LAD/D1 bifurcation and RCA CTO in an outpatient setting, which was successfully performed later. The repeated echocardiogram showed an LVEF of 58% with no regional wall motion abnormalities.

Acute coronary syndrome (ACS) in the setting of LM bifurcation lesion is a challenging condition as it frequently results in cardiogenic shock. For this population, hemodynamic support during PCI is invaluable. While studies have compared the provisional 1-stent strategy versus a planned 2-stent strategy, patients with ACS are frequently underrepresented. Our case helps illustrate that: First, mechanical circulatory support with Impella CP during high-risk PCI is a complimentary approach. This is particularly relevant to our case as the patient also suffers from RCA CTO. Second, a planned 2-stent strategy is a feasible option for LM bifurcation PCI even in the setting of ACS.