Abstract 11593: The Critical Role of Transthoracic Echocardiography in the Evaluation of Cardiogenic Shock and Takotsubo Cardiomyopathy

Abstract

Introduction: Cardiogenic shock occurs in 10% of patients with takotsubo cardiomyopathy (TTC) as a result of severe systolic dysfunction, or left ventricular outflow tract (LVOT) obstruction. Methods: Case report and review of the literature. Results: A 62-year-old female with a history of hypertension and diabetes mellitus presented with lightheadedness, shortness of breath, and chest discomfort. She was hemodynamically unstable, tachycardic, and hypotensive (70/40 mmHg). Her EKG showed sinus tachycardia at 101 BPM with 1 mm ST depression in leads II, III, AVF; V3-V6. Chest radiograph revealed pulmonary edema. High-sensitive troponin was 146.7. She was intubated for respiratory distress and had rapidly increasing vasopressor requirements. Emergent coronary angiography revealed nonobstructive coronary artery disease. A left ventriculogram revealed apical ballooning with an estimated ejection fraction of 25%, consistent with TTC. Transthoracic echocardiogram (TTE) showed severe mid and apical LV hypokinesis with basal hyperkinesis. Additionally, systolic anterior motion (SAM) of the mitral valve (MV) was noted, with a peak LVOT gradient of 7 mmHg. The patient improved clinically, and all support was weaned off. However, she later acutely developed recurrent respiratory distress and hypotension. Repeat TTE showed LVOT obstruction with a gradient of 40 mmHg due to increased basal hyperkinesis and SAM. The choice of vasopressor was switched from norepinephrine to phenylephrine to reduce the obstruction. She clinically improved and metoprolol succinate was added to reduce basal hypercontractility and improve left ventricular filling. Conclusions: Differentiating the mechanism of shock in TTC can easily be accomplished with TTE, and is essential to guiding treatment. The initial acute systolic dysfunction was effectively managed with norepinephrine, dopamine, and an intra-aortic balloon pump. She later developed LVOT obstruction as her systolic function improved. This was recognized with TTE and led to an appropriate change in vasopressor, as norepinephrine would have worsened the obstruction. This highlights the importance of early TTE in patients presenting with undifferentiated shock, especially when TTC is suspected.