2022 SCAI SHOCK

Title:
SCAI Stage B Cardiogenic Shock: Impact Of Cardiac Arrest and Distributive Shock

Introduction:
Cardiogenic shock presents along the spectrum of hemodynamic instability. Early stages of cardiogenic shock typically involve stable macrovascular hemodynamics. The impact of cardiac arrest on Society of Cardiovascular Angiography and Intervention (SCAI) Stage B cardiogenic shock has been infrequently reported.

Clinical Case:
A 55-year-old obese female presented with chest pain, shortness of breath and diaphoresis of a few hours duration. Her past history was significant for venous thromboembolism, cerebrovascular accident and hyperlipidemia. Initial electrocardiogram was unremarkable. Subsequently, she developed ventricular tachycardia/ventricular fibrillation (VT/VF) arrest. She received immediate high-quality advanced cardiac life support with return of spontaneous circulation within a few minutes. Repeat electrocardiogram demonstrated anterior ST-segment-elevation myocardial infarction (STEMI) with associated inferolateral reciprocal changes. Due to her anterior STEMI, she was taken to the cardiac catheterization laboratory where diagnostic angiogram demonstrated 100% proximal left anterior descending (LAD) occlusion, left ventricular (LV) end-diastolic pressure of 42 mmHg and estimated LV ejection fraction of 35-40%. During her angiogram, she developed two additional episodes of VF/VT which necessitated defibrillation. She continued to be hypertensive and tachycardic with short bursts of non-sustained VT. She subsequently lost consciousness needing endotracheal intubation. Due to her sustained VT, we elected to treat her with deep sedation, paralysis, and amiodarone.

At this time, due to her hemodynamic instability, she received norepinephrine and epinephrine infusions, and mechanical circulatory support with an Impella CP through right femoral artery access (Abiomed, Danvers, MA). A 6 French EBU 3.5 guide was used to engage the left main and an Asahi Sion blue wire was used to cross the LAD. After predilatation with a 2.5 x 15 mm semi-compliant balloon and aspiration thrombectomy, a 3.5 x 38 mm drug-eluting stent was inserted and postdilated using 3.5 and 5.0 mm non-compliant balloons. Right heart catheterization demonstrated significant improvement in her filling pressures.

Post procedure, she was transferred to the cardiac intensive care unit. Her hemodynamics showed a decrease in biventricular filling pressures concerning for superimposed distributive shock. She developed leukocytosis and her tracheal aspirates were positive for Staph aureus. She was treated appropriately with broad-spectrum antibiotics, and additional vasopressor medications. Her mechanical circulatory support was weaned and removed on postprocedure day #2. She received fluid boluses, was extubated and ambulated. She developed acute kidney injury secondary to multiple etiologies, however was diuresing well with minimal assistance. She continued to do well and was dismissed home on warfarin and ticagrelor for management of her DVT and coronary disease. Her echocardiogram prior to discharge demonstrated normalization of LV ejection fraction (60%) with normal right ventricular systolic pressure of 25 mmHg.

Discussion:
Cardiogenic shock follows a spectrum of SCAI stages and has significant variability in presentation based on concomitant cardiac arrest. The combination of cardiac arrest and cardiogenic shock is associated with worse outcomes. Furthermore, in patients with cardiogenic shock, often, concomitant distributive shock necessitates frequent reevaluation of clinical needs. Use of a pulmonary artery catheter assist with close monitoring and management of hemodynamics.