Detection of Myocardial Dysfunction in Non-severe Subarachnoid Hemorrhage (WFNS 1-2) Using Speckle-tracking Echocardiography (STRAIN)

Overview

Subarachnoid hemorrhage (SAH) can cause transient myocardial dysfunction. Recently, it have been reported that myocardial dysfunctions that occur in SAH are associated with poor outcomes. It therefore appears essential to detect theses dysfunctions with the higher sensitivity as possible. Strain measurement using speckle-tracking echocardiography may detect myocardial dysfunction with great sensitivity. The main objective of this study is to assess the prevalence of myocardial dysfunction in "non-severe" SAH (defined by a WFNS grade 1 or 2), using speckle-tracking echocardiography. This study also aims to analyse Strain measurement with classical echocardiography and serum markers (troponin, BNP) of cardiac dysfunction.

Cardiac complication, occurring in the early phase of SAH has been well described. It seems that the pathophysiological mechanism involves vegetative hyperactivity due to the acute cerebral injury. It has been shown that stress cardiomyopathy is associated with delayed cerebral ischemia (DCI) and poor outcomes. Manifestations of stress cardiomyopathy are changes in electrocardiogram, release of cardiac biomarkers such as troponin and BNP, and echography evidence of impaired left ventricle ejection fraction with the use of Simpson technique and regional wall motion abnormalities. These two techniques bear intra-observer variability. A new method is available to assess left ventricular contractility at the bedside. Two-dimensional speckle-tracking images with echocardiography allows one to track a natural myocardial marker within the myocardium by standard transthoracic echocardiography. It provides unique insights into myocardial function such as tissue deformations and strain rate, which is the rate of deformation. This method is more sensitive than classical echographic left ventricular ejection fraction evaluation and bears very low interobserver variability. The Global Longitudinal Strain (GLS) is the most studied parameter. Early detection of cardiac dysfunction in SAH followed by appropriate monitoring and management may improve outcome in SAH. This is a prospective, observational and mono-center study. Patients with "non-severe" SAH will benefit from an echocardiography where Left Ventricular Ejection Fraction (LVEF) and GLS will be assessed on day 1, 3 and 7 following the acute injury.