Anterior (frontal) view of the opened heart. White arrows indicate normal blood flow.
Editor-In-Chief: C. Michael Gibson, M.S., M.D. 
Left heart is a term used to refer collectively to the left atrium and left ventricle of the heart; occasionally, this term is intended to reference the left atrium, left ventricle, and the aorta collectively.
The left atrium receives oxygenated pulmonic blood from the pulmonary veins. The blood is then pumped through the mitral valve into the left ventricle, which in turn pumps the blood through the aortic valve into the aorta.
The left side of the heart is thicker than the right because of the requirement to pump blood from the left throughout the body, as opposed to the right side pumping only through the lungs.
See also: Right heart
|Anatomy of torso, cardiovascular system: heart|
|Structures||atria (interatrial septum, musculi pectinati) • ventricles (interventricular septum, trabeculae carneae, chordae tendinae, papillary muscle) • valves • cusps|
|Regions||base • apex • grooves (coronary/atrioventricular, interatrial, anterior interventricula, posterior interventricular) • surfaces (sternocostal, diaphragmatic) • borders (right, left)|
|Right heart||(vena cavae, coronary sinus) → right atrium (auricle, fossa ovalis, limbus of fossa ovalis, crista terminalis, valve of the inferior vena cava, valve of the coronary sinus) → tricuspid valve → right ventricle (conus arteriosus, moderator band/septomarginal trabecula) → pulmonary valve → (pulmonary artery and pulmonary circulation)|
|Left heart||(pulmonary veins) → left atrium (auricle) → mitral valve → left ventricle → aortic valve (aortic sinus) → (aorta and systemic circulation)|
|Layers||pericardium: fibrous pericardium • serous pericardium (pericardial cavity, epicardium/visceral layer) • pericardial sinus|
myocardium • endocardium • cardiac skeleton (fibrous trigone, fibrous rings)
|Conduction system||Cardiac pacemaker • SA node • AV node• bundle of His • Purkinje fibers|