Refractory Acute Myocardial Infarction Cardiogenic Shock Due to Left Ventricular Outflow Tract Obstruction.

BACKGROUND

Optimal management of cardiogenic shock (CS) after acute myocardial infarction (AMI) frequently consists of inotropes and consideration of a mechanical circulatory support. However, this initial approach may be counterproductive in some CS phenotypes.

CASE SUMMARY: A 75-year-old female presented with AMI of the left anterior descending artery and underwent successful revascularization. Initial postprocedural management including intra-aortic balloon pump and inotropes paradoxically worsened CS. Prompt echocardiography illustrated an unrecognized left ventricular outflow tract obstruction (LVOTO) due to an apical aneurysmal infarct and compensatory hypercontractile basal segments. Echocardiography-guided weaning of the intra-aortic balloon pump and inotropes resulted in improved hemodynamics.

DISCUSSION: Dynamic LVOTO is an underrecognized mechanical complication of anterior-wall AMI-CS. Clinical awareness and echocardiography can help identify anatomical predisposition to LVOTO and direct appropriate hemodynamic support.

TAKE-HOME MESSAGE: This case highlights the importance of recognizing LVOTO in AMI-CS where afterload-reducing mechanical circulatory support and inotropes can counterintuitively worsen hemodynamics.