An Intraoperative Diagnosis of Dynamic Left Ventricular Outflow Tract Obstruction Using Transesophageal Echocardiography Leads to the Treatment with Intravenous Disopyramide

Early dynamic left intraventricular obstruction is associated with hypovolemia and high mortality in septic shock patients

Introduction

Based on previously published case reports demonstrating dynamic left intraventricular obstruction (IVO) triggered by hypovolemia or catecholamines, this study aimed to establish: (1) IVO occurrence in septic shock patients; (2) correlation between the intraventricular gradient and volume status and fluid responsiveness; and (3) mortality rate.

Method

We prospectively analyzed patients with septic shock admitted to a general ICU over a 28-month period who presented Doppler signs of IVO. Clinical characteristics and hemodynamic parameters as well as echocardiographic data regarding left ventricular function, size, and calculated mass, and left ventricular outflow Doppler pattern and velocity before and after fluid infusions were recorded.

Results

During the study period, 218 patients with septic shock were admitted to our ICU. IVO was observed in 47 (22 %) patients. Mortality rate at 28 days was found to be higher in patients with than in patients without IVO (55 % versus 33 %, p < 0.01). Small, hypercontractile left ventricles (end-diastolic left ventricular surface 4.7 ± 2.1 cm²/m² and ejection fraction 82 ± 12 %), and frequent pseudohypertrophy were found in these patients. A rise ≥12 % in stroke index was found in 87 % of patients with IVO, with a drop of 47 % in IVO after fluid infusion.

Conclusion

Left IVO is a frequent event in septic shock patients with an important correlation with fluid responsiveness. The mortality rate was found to be higher in these patients in comparison with patients without obstruction.