This book focuses on a new clinical algorithmic approach to acute patient care based on the combination of electrocardiography (ECG) and echocardiography performance and interpretation, now renamed: ECG-sonography or electrosonography. The combination of these two basic skills improves patient management by healthcare providers in the acute setting. ECG is one of the oldest diagnostic tools in evaluating patients with cardiovascular symptoms and multiple and complex criteria for its interpretation have been developed over the past decades. The use of point of care ultrasound based on handheld echocardiography has recently emerged as an important clinical tool, particularly in the emergency department (ED) and intensive care unit. These studies are mainly performed by non-cardiologists including intensivists and ED physicians in addition to the physical exam and standard diagnostic tests such as the chest X-ray and laboratory tests to evaluate patients quickly and efficiently. Cardiac Electrosonography provides a new algorithmic approach to ECG interpretation and a simple tutorial of echocardiography performance and interpretation with a major focus on handheld echocardiography. It includes representative cases of patients presenting to the ED with a specific, acute cardiovascular symptom and demonstrates appropriate use of both ECG and echocardiography to improve patient management and outcome. It therefore represents an essential guide to this hybrid procedure for all practicing and trainee cardiologists and all healthcare professionals who manage these patients.