It is calculated as the average of the peak systolic longitudinal strain from all LV segments in apical four, three and two chamber views. Moreover, it improves risk prediction beyond LVEF assessment in patients with HFrEF. Global longitudinal strain may be more sensitive than LVEF as a measure of LV systolic function, allowing early changes in patients at high risk to be detected. Strain is defined as the change in length of a myocardial segment relative to its resting length, while strain rate is defined as the rate of such deformation. Moreover, it permits the measurement of myocardial strain and strain rate. It allows fast and highly automated LV chamber quantification, producing accurate and reproducible LVEF estimation. Speckle tracking echocardiography analyses LV deformation by tracking cardiac motion from image intensities (the speckled pattern of the myocardium). However, it remains dependent on good acoustic windows and scanning technique, rendering it subject to many of the same limitations as 2D TTE.Īssessment of myocardial deformation is an emerging technique that may have an important clinical role in the diagnosis of HFrEF. 3D echocardiography provides volumes with minimal postprocessing requirements, and is more accurate and reproducible than 2D assessment. More comprehensive evaluation of LV systolic function is possible using advanced imaging techniques, such as 3D echocardiography, speckle tracking and cardiac MRI (CMR). Reproduced with permission from BioMed Central under a Creative Commons CC-BY 2.0 licence. B: On cardiac MRI, contours are drawn on the short axis cine stack in end-diastole and end-systole. The endocardial borders are traced in the four chamber and two chamber views in end-diastole and end-systole. This may concomitantly allow the diagnosis of LV thrombus when present.Īssessment of Left Ventricular Ejection Fraction on Transthoracic Echocardiography and Cardiac MRIĪ: Left ventricular ejection fraction can be assessed on 2D transthoracic echocardiography using the biplane method. If required, intravenous contrast can be administered to better delineate the endocardial border, increasing the feasibility of biplane volume analysis and improving the accuracy of LVEF estimation. Moreover, poor image quality can lead to foreshortening of the ventricles and, therefore, underestimation of the volumes. This method relies on assumptions regarding the geometric shape of the LV. Measurement areas are acquired in two single planes from which inferences are made to estimate the LV shape and obtain 3D volumes ( Figure 1A). 2D LVEF is typically calculated using the biplane method of disks (modified Simpson’s) method. 2D transthoracic echocardiography (TTE) remains the initial modality recommended for the assessment of LVEF. Accordingly, accurate estimation of LVEF remains the cornerstone of HFrEF diagnosis. The current European Society of Cardiology guidelines define HFrEF as the presence of signs and symptoms of HF and a reduced ejection fraction (LVEF ≤40%). The Role of Imaging in the Diagnosis of HFrEF This review summarises the role of cardiac imaging in HfrEF, with a focus on diagnosis, phenotyping, assessment of aetiology, therapy planning and prognostication. In addition to providing accurate volumetric assessment, cardiac imaging has evolved to offer functional, haemodynamic and tissue characterisation. Furthermore, identification of the underlying aetiology is of great importance, allowing the personalisation of treatment and prognostication. What makes cardiac imaging the cornerstone of the assessment of HFrEF is the identification of impaired left ventricular contraction and reduced left ventricular ejection fraction, which are the essentials of diagnosing HFrEF, which is followed by initiating disease-modifying therapy. Approximately half of all HF patients have reduced ejection fraction (LVEF <40%) at rest. Three distinct phenotypes based on left ventricular ejection fraction (LVEF) have been described: HF with preserved ejection fraction (HFpEF), HF with mildly reduced ejection fraction and HF with reduced ejection fraction (HFrEF). The prevalence of HF in the developed world approximates 1–2% of the adult population, rising to >10% in those aged >75 years. Heart failure (HF) remains an important cause of morbidity and mortality worldwide.
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |