AN22.1-7 | Heart & Pericardium — Glossary

A multi-layered protective sac around the heart consisting of an outer fibrous pericardium and inner serous pericardium (parietal and visceral layers)

Life-threatening compression of the heart by fluid in the pericardial cavity, identified by Beck's triad: hypotension, distended neck veins, muffled heart sounds

A pericardial recess behind the aorta and pulmonary trunk, used by surgeons to pass a clamp during cardiac bypass surgery

A pericardial cul-de-sac behind the left atrium bounded by pulmonary vein reflections

A smooth muscular ridge in the right atrium separating the smooth-walled sinus venarum from the rough pectinate muscle area

A depression in the interatrial septum, remnant of the foramen ovale; site of atrial septal defects

The septomarginal trabecula carrying the right bundle branch from the septum to the anterior papillary muscle in the right ventricle

Tendinous cords connecting papillary muscles to AV valve leaflets, preventing valve prolapse during ventricular systole

Dense connective tissue rings around the heart valves providing structural support, valve attachment, and electrical insulation between atria and ventricles

Left anterior descending artery running in the anterior interventricular groove, supplying the anterior wall and anterior two-thirds of the interventricular septum

LCx, running in the left AV groove supplying the lateral wall of the left ventricle

RCA arising from the right aortic sinus, supplying the right ventricle, SA node (60%), AV node (80%), and giving the PDA in right-dominant hearts

Determined by which artery gives the PDA; right-dominant (85%, RCA gives PDA), left-dominant (15%, LCx gives PDA)

Death of heart muscle from complete coronary artery occlusion, territory determined by which artery is blocked

The main venous channel of the heart running in the posterior AV groove, collecting most cardiac venous blood and draining into the right atrium

The sinoatrial node, the heart's natural pacemaker in the right atrium generating impulses at 60-100 bpm

The atrioventricular node in the triangle of Koch, providing a 0.1 second delay allowing atrial contraction to complete before ventricular contraction

The atrioventricular bundle, the only electrical connection between atria and ventricles, crossing the fibrous skeleton

Specialized conducting fibres in the subendocardial layer that rapidly distribute impulses throughout the ventricular myocardium

Emergency drainage of pericardial fluid by inserting a needle below the xiphoid process, directed toward the left shoulder

Three signs of cardiac tamponade: low blood pressure, distended neck veins, and muffled heart sounds

Chest pain from myocardial ischaemia when coronary narrowing exceeds 70%, occurring during exertion

Build-up of cholesterol-laden plaques inside coronary artery walls, the anatomical basis of ischaemic heart disease