Left Ventricular Diastolic Function in the Critically Ill

Diastolic dysfunction is a common and important cause of morbidity and mortality in the intensive care unit. Despite its high prevalence, it is often overlooked as a cause of decompensation in patients with preserved systolic function. Patients with diastolic dysfunction experience exaggerated shifts in left ventricular end-diastolic pressure with small changes in afterload and preload due to deviations in the left ventricular pressure-volume curve. For this reason, patients with diastolic dysfunction may present in a multitude of ways to the intensive care unit including hypertensive acute pulmonary edema, azotemia, renal failure, hypotension, and profound shock. The use of point-of-care echocardiography is an important tool that can be utilized by the bedside clinician in assessing diastolic function. Mitral flow and tissue Doppler velocities can provide a wealth of information to help categorize the grade of diastolic dysfunction. These diastolic parameters can be used to provide a non-invasive estimate of left sided filling pressures and augment clinical decision making in the critically ill. As patients exist along a spectrum, diastolic function can be assessed in response to various therapies that affect preload and afterload. A full understanding of the hemodynamics of diastolic filling can be utilized in a range of clinical scenarios such as predicting weaning failure after a spontaneous breathing trial and assessing volume responsiveness. Diastolic dysfunction also plays an important role in prognostication as it is associated with worse outcomes in patients presenting with sepsis and myocardial infarction. In conclusion, with the advent of point-of-care echocardiography, evaluation of diastolic function is an important aspect of assessing hemodynamics and can help augment clinical decision making for the intensivist at the bedside.