Angiology

1. Angiology

2. Composition • Cardiovascular system • Lymphatic system

3. The Cardiovascular System Ⅰ.Introduce Ⅰ) The organization — heart central pump — arteries carry blood away from the heart — capillaries — veins transport blood from the capillaries

4. Blood circulation • Systemic circulation • left ventricle→aorta and its branches→capillaries of body→superior and inferior vena cava→right atrium

5. Systemic circulation • Here, the substance exchange between the blood and tissue cells through capillary wall takes place. The exchange includes oxygen, carbon dioxide, nutrients, water and inorganic ions, vitamins, hormones, metabolic products, antibodies, and defensive cells of various kinds. Then the arterial blood(rich in oxygen and nutrients) becomes venous blood(rich in carbon dioxide and metabolic products ) ,go through superior vena cava, inferior vena cava, coronary sinus, and the tributaries of them toward the right atrium. • Consequentially, this blood enters to the right ventricle.

6. 2.The pulmonary (lesser) • circulation right ventricle • pulmonary trunk • right and left pulmonary • Arteries pulmonary • capillaries(in lungs) • pulmonary veins • left atrium

7. blood gives off carbon dioxide and acquires oxygen. Thus, the venous blood becomes arterial blood, go through the pulmonary veins to the left atrium.

8. Heart • Position and relation • External morphology • Cardiac chambers • Conduction • Vessels • Pericardium

9. Position • Lies within the pericardium in middle mediastinum • Behind the body of sternum and coastal cartilages 2 to 6 • In front of thoracic vertebrae 5 to 8 • A third of it lies to the right of median plan and 2/3 to the left

10. Surface markings of heart • Right border－corresponds to a line running from the upper border of right third costal cartilage ±1.2cm from the margin of sternum, downwards to sixth sternocostal joint • Apex－in the fifth left intercostal space 7~9cm from the midline • Left border－represented by a line running from apex upwards and medially to a point on lower border of left second costal cartilage ±1.2cm from sternal margin • Lower border－represented by a line joint the lower end of right border to apex

11. External morphology one apex, one base, two surfaces three borders three grooves

12. the apexformed by the left ventricle • the basefaces backward,upward and to the right. Formed mainly by the left atrium and partly by the right atrium. • two surfaces: sternocostal and diaphragmatic surfaces • three borders: right,left and inferior borders • *the cardiac apecial incisure is on the inferior border and right to the apex • *atrioventricular crux is a point of the coronary and posterior interventricular grooves. It is a important superficial mark • three grooves: coronary groove • ant. interventricular groove • post. interventricular groove • Interatrial sulcus －separates the two atria and is hidden by pulmonary trunk and aorta in front

13. External characteristics－a hollow muscular organ, pyramidal in shape , somewhat larger than a closed fist; consists of four chambers (right and left atria, right and left ventricles) • Cardiac apex is formed by left ventricle and is directed downwards and forwards to the left. It lies at the level of the fifth left intercostal space, 1~2cm medial to the left midclavicular line (9cm from the midline) • Cardiac base is formed by the left atrium and to a small extent by the right atrium. It faces backward, upward and to the right

14. Two surface • Sternocostal surface is formed mainly by the right atrium and right ventricle, and a lesser portion of its left is formed by the left auricle and ventricle. It is directed forwards and upwards • Diaphragmatic surface is formed the ventricles－chiefly the left ventricle, directed backwards and downwards, and rest upon the central tendon of the diaphragm

15. Three borders • Right border－vertical, is formed entirely by right atrium • Left border－round, is mainly formed by the left ventricle and partly by the left auricle • Inferior border－horizontal, is formed by the right ventricle and cardiac apex

16. Three grooves • Coronary sulcus (circular sulcus) which marks the division between atria and ventricles, contains the trunks of the coronary vessels and completely encircles the heart • Interventricular grooves －anterior and posterior, mark the division between ventricles (which separates the RV from the LV), the two grooves extend from the base of the ventricular potion to a notch called: the cardiac apical incisure Atrioventricular crux －a junction of the posterior interventricular groove and coronary sulcus

17. Chambers • right atrium • right ventricle • left atrium • left ventricle

18. Chambers of the heart Right atrium (RA) Three inlets • Orifice of superior vena cava returns blood to the heart from the upper half of the body • Orifice of inferior vena cava －returns blood to the heart from the lower half of the body • Orifice of coronary sinus －returns blood to the heart from the cardiac muscle One outlet －right atrioventricular orifice

19. Crista terminalis－vertical ridge that from superior vena cave to inferior vena cave • Sulcus terminalis －groove on exterior of heart that corresponds to crista terminalis Two parts－separated externally by sulcus terminalis and internally by the crista terminalis • Atrium proper • In front of the ridge • Pectinate muscles in wall • Right auricle －a small conical muscular pouch, projects to the left from the root of superior vena cava, pectinate muscles in wall

20. Orifice of coronary sinus Lies posterior to the ridge • Smooth walls • Fossa ovalis －an oval depression, a remnant of the fetal foramen ovale, on the lower part of interatrial septum, the most common location of atrial septal defects (ASD) • Limbus fossae ovalis– prominent margin of fossa ovalis

21. Right ventricle(RV) Receives deoxygenated blood from right atrium through right atrioventricular orifice • One inlet－right artrioventricular orifice • One outlet－orifice of pulmonary trunk • Two parts－divided by the supraventricular crest, a muscular ridge between right atrioventricular orifice and orifice of pulmonary trunk

22. Inflow tract－rough walls • Trabeculae carneae－irregularly arranged bundles of myocardium • Septomarginal trabecula －extends from interventricular septum to base of anterior papillary muscle, contains right bundle branch • Papillary muscles－conical-shaped , anterior, posterior and septal Out flow tract • Conus arteriosus cone-shaped, smooth area leading upward to orifice of pulmonary trunk • Pumps blood through pulmonary orifice to pulmonary trunk

23. Left atrium (LA) • Left auricle－projecting to the right, pectinate muscles in wall • Four inlets－four orifices of pulmonary veins open through the posterior wall • One outlet－left atrioventricular orifice, blood leaves through left atrioventricular orifice to left ventricle

24. Left ventricle (LV) • Has wall three times thicker than that of right ventricle • One inlet－left atrioventricular orifice • One outlet－aortic orifice • Two parts－divided by anterior cusps of mitral valve • Inflow tract－rough walls • Outflow tract – aortic vestibule, smooth area leading to aortic orifice

25. Valves Tricuspid valve • Guards right atrioventricular orifice • Three triangular cusps: anterior, posterior and septal, the base of cusps are attached to fibrous ring surrounding the atrioventricular orifice • Chordae tendineae －fine, white, connective tissue cords, attach margin of cusps to papillary muscles

26. Mitral valve • Guards left atrioventricular orifice • Two triangular cusps－anterior and posterior with commissural cusps between them (posteromedial and anterolateral commissures) • Similar structures to those of right

27. Similar functions for right and left atriventricular valves • Open during diastole to allow blood to enter ventricles from atria • Closed during systole to prevent regurgitation of blood into atria

28. Valve of pulmonary trunk • Guards the orifice of pulmonary trunk • Has three semilunar cusps – each with free border that has central nodules of semilunar valve

29. Aorti vavle • Guards the aortic orifice • Three semilunar cusps (right, left and post) • Three aortic sinuses – bulges in aortic wall at level of valve that correspond to cusps • Right－contains opening of right coronary artery • Left－contains opening of left coronary artery • Posterior－no opening

30. Similar functions for pulmonary and aortic valves • Opening during systole, with cusps pressed toward wall of vessel as blood is forced upward • Closed during diastole • Ventricular pressure drops in diastole • Floating together of valve cusps, with free borders meeting, thus closing the valve

31. Structure of the heart Walls of heart • Endocardium－inner coat of the heart wall, and continuous with the valve flaps • Myocardium • Arranged spirally • Attached to fibrous rings surrounding the four orifices of heart • Epicardium －serous membrane (visceral pericardium)

32. Interatrial septum • Located between right and left atria • Contains fossa ovalis and limbus Interventricular septum • Located between right and left ventricles • Has upper membranous part • Has thick lower muscular part

33. Fibrous skeleton • Fibrous rings that surround the atrioventricular, pulmonary, and aortic orifices • Left and right fibrous trigons • right fibrous trigon sits among the annuli of the bicuspid valve, the tricuspid valve and the aotric valve. Inferiorly it adheres to the muscular part of the interventricular septum, and forward connects with the membranous part of the interventricular septum. Because of its position located to the center of the heart, it is also called the central fibrous body. • Left fibrous trigon sits between the annulus of bicuspid valve and the annulus of the aortic valve. This trigone is smaller than the right one.

34. Conduction System It is consists of the special cardiac muscles None of these structures are macroscopic, but their locations can be noted. 5 parts: sinoatrial node Internodal tracts atrioventricular node, atrio-ventricular bundle Left and right branches Purkinje fibers.

35. Cardiac muscle has an intrinsic rhythmicity that allows the heartbeat to originate in and be conducted through the heart without extrinsic stimulation. Specialized strands of interconnecting cardiac muscle tissue that coordinate cardiac contraction constitute the conduction system. • The conduction system enables the cardiac cycle, which refers to the events surrounding the filling and emptying of the chambers of the heart. The conduction system consists of specialized tissues that generate and distribute electrical impulses through the heart.

36. Conduction system of heart • Consists of specialized myocardial cells Sinuatrial node (SA node) • Called the pacemaker cell (P cell) • Located at the junction of right atrium and superior vena cava, upper part of the sulcus terminalis, under the epicardium

37. The SA node initiates the cardiac cycle by producing an electrical impulse that spreads over both atria, causing them to contract simultaneously and force blood into the ventricles. The basic depolarization rate of the SA node is 70 to 80 times per minute.

38. The impulse then through internodal tracts, located in the inferior portion of the interatrial septum just above the orifice of the coronary sinus passes to the atrioventricular node. From here, the impulse continues through the atrioventricular bundle, located at the top of the interventricular septum. The atrioventricular bundle divides into right and left bundle branches, which are continuous with the conduction myofibers within the ventricular walls —Purkinje fibers. Stimulation of these fibers causes the ventricles to contract simultaneously.

39. Atrioventricular node (AV node) • Located in the lower part of interatrial septum just above the orifice of coronary sinus, under the endocardium • Lower part related to membranous part of interventricular septum Atrioventricular bundle (AV bundle) • Passes forward through right fibrous trigon to reach inferior border of membranous part • Divides into right and left bundle branches at upper border of muscular part of interventricular septum

40. Right and left bundle branches Right bundle branch－passes down on right side of interventricular septum to reach the septomarginal trabecular and into the base of anterior papillary muscle. Here it becomes continuous with the fibers of Purkinje fibres • Left bundle branch－passes down on left side of interventricular septum beneath the endocardium. It usually divides into two branches, which eventually become continuous with the Purkinje fibers Purkinje fibers －continuous with myocardium

41. The wall of the heart has its own supply of systemic blood vessels to meet its vital needs. The myocardium is supplied with blood by the right and left coronary arteries. These two vessels arise from the ascending part of the aorta, at the location of the aortic (semilunar) valve. The coronary arteries encircle the heart within the atrioventricular sulcus, the depression between the atria and ventricles. Two branches arise from both the right and left coronary arteries to serve the atrial and ventricular walls.

42. Arterial supply Left coronary arteryArises from left aortic sinus • Runs between pulmonary trunk and left auricle into coronary sulcus • Branches • Anterior interventricular branch travels downward in anterior interventricular groove around inferior margin of heart to posterior interventricular groove • Circumflex branch －travels to left in coronary sulcus to posterior aspect • Distribution－supplies left atrium and ventricle, lesser portion of anterior wall of right ventricle, and anterior 2/3 of interventricular septum

43. Right coronary artery • Arises from the right aortic sinus • Runs forward between right auricle and pulmonary trunk into coronary sulcus • Branches • Right marginal branch －travels along inferior border • Posteror interventricular branch travels downward in posterior interventricular groove, it anastomosises near the apex with the anterior interventricular branch of the left coronary artery • Distribution: supplies right atrium and ventricle, posterior 1/3 of interventricular septum, posterior wall of left ventricle, the sinuatrial node and atrioventricular node

44. A heart attack often involves a clot in the coronary arteries or their branches. In this illustration, a clot is shown in the location of #1. Area #2 shows the portion of the damaged heart that is affected by the clot. Image by J. Heuser courtesy of Wikipedia.

45. Venous drainage Coronary sinus • Located in right atrium, runs transversely in the groove between the left atrium and ventricle on the posterior surface of the heart. • Carries most of venous blood from myocardium to right atrium • Tributaries • Great cardiac vein • Middle cardiac vein • Small cardiac vein

46. Anterior cardiac veins －3~4 small vessels, drain into right atrium • Smallest cardiac veins－drain into all chambers, mainly atria

47. Pericardium 1. It comprises 2 sacs: —the fibrous pericardium —the serous pericardium: *parietal layer *visceral layer

48. The parietal pericardium is a loose fitting serous sac of dense fibrous connective tissue that encloses and protects the heart. It separates the heart from the other thoracic organs and forms the wall of the pericardial cavity , which contains a watery, lubricating pericardial fluid. The parietal pericardium is actually composed of an outer fibrous pericardium and an inner serous pericardium. • The visceral pericardium is serous pericardium • It is the serous pericardium that produces the lubricating pericardial fluid that allows the heart to beat in a kind of frictionless bath. • .

49. The potential space between the parietal and visceral layers is called the pericardial cavity. Normally, the cavity contains a small amount of serous fluid which acts as a lubricant to facilitate movements of the heart.

50. The sinuses of pericardium Transverse sinus of pericardium －posterior to ascending aorta and pulmonary trunk, anterior to superior vena cava and left atrium. • The Ascending aorta and the pulmonary trunk can be clamped by the sinus to block the blood stream temporarily in operation of the heart. • Oblique sinus of pericardium－cul-de-sac , posterior to heart, bounded by pulmonary veins on either side, lies behind the left atrium