Anatomi dan Fisiologi Sistem Cardiovaskuler

Presentasi berjudul: "Anatomi dan Fisiologi Sistem Cardiovaskuler"— Transcript presentasi:

1 Anatomi dan Fisiologi Sistem Cardiovaskuler
Oleh : Faik Agiwahyuanto, S.Kep., M.Kes

2 Pembahasan : Letak dan Posisi Jantung Macam dan pengisi jantung
Fungsi Jantung Dasar permasalahan jantung dan tindakan pemeriksaan jantung

3 Jantung (The Heart)

4

5 Sistem Peredaran Darah pada Manusia
Sistem ini merupakan sistem peredaran darah tertutup, karena peredaran darah hanya dari jantung dan melalui pembuluh darah. Mekanisme kerjanya : Jantung memompa darah Pembuluh darah mengalirkan dan mensirkulasikan darah ke semua bagian tubuh. Fungsi sistem kardiovaskuler adalah mengantarkan oksigen, nutrisi makanan, menghilangkan karbon dioksida dan sampah sisa metabolisme tubuh. Peredaran darah ada 2 macam = terbuka dan tertutup Peredaran darah tertutup adalah peredaran darah tidak hanya dari jantung, tetapi juga dari sel serta tidak melalui pembuluh darah, tetapi melalui sel atau jaringan lainnya. Seperti pada serangga atau hewan yang tidak ber sel darah merah. Pembuluh drah manusia memang dirancang dari jantung ke seluruh tubuh, tetapi pembuluh darah manusia ada pembuluh darah arteri dan vena. Arteri adalah pembuluh darah besar dan menghantarkan ke seluruh organ tubuh, sedangkan vena adalah pembuluh darah balik yang mengantarkan ke jantung.

6 Lokasi Penampang Jantung
Lokasi berada di : RONGGA THORAX diantara Paru-Paru (kanan dan kiri) Letak pastinya pada garis iga kedua, diantara midsternal dan sternum, diatas diafragma. Bawah adalah APEX yang lancip pada sisi kirinya. Ukurannya “SEKEPALAN Tangan Manusia” berat gr Jantung merupakan organ istimewa yang berisi otot dan bekerja seperti otot polos (kerja diluar dari kemauan), tetapi susunannya seperti serat lintang. Otot pada manusia ada 3 macam, yaitu : Otot polos = otot yang bekerja di luar dari perintah otak atau kemauan sadar manusia Otot lurik = otot yang bekerja dengan sesuai perintah otak manusia Otot jantung = otot yang bekerja seperti otot polos tetapi bentuknya seperti oto lurik, dan hanya di jantung

7 Eksternal Heart Anatomy

8 Lapisan Jantung Endocardiac / Endokardium = Merupakan lapisan jantung yang terdapat di sebelah dalam sekali yang terdiri dari jaringan endotel (selaput lendir) yg melapisi permukaan rongga jantung. Miocardiac / Miokardium = merupakan lapisan inti dari jantung yang terdiri dari otot-otot jantung. Pericardiac / Perikardium = lapisan jantung sebelah luar yang merupakan selaput pembungkus terdiri dari 2 lapisan (parietalis / parietal) dan (visceralis / viseral) yang bertemu di pangkal jantung membentuk kantung jantung

9 Jantung : Ruang / Chambers
Sisi kanan dan kiri dipisahkan dengan pompa – pompa jantung Jantung memiliki 4 ruang = Atrium / Atria / Serambi Fungsinya menampung darah dari luar jantung yang nantinya akan dialirkan menuju ventrikel Terdapat atrium kanan dan atrium kiri Ventrikel / Ventricels / Bilik Fungsinya mengisi ruangan dengan darah dari tampungan atrium. Terdapat ventrikel kanan dan ventrikel kiri.

10 Sirkulasi Darah pada Manusia

11 Pathway pada darah yang melalui jantung dan paru
Right atrium  tricuspid valve  right ventricle Right ventricle  pulmonary semilunar valve  pulmonary arteries  lungs Lungs  pulmonary veins  left atrium Left atrium  bicuspid valve  left ventricle Left ventricle  aortic semilunar valve  aorta Aorta  systemic circulation

12 The Heart: Valves Allow blood to flow in only one direction
Four valves Atrioventricular valves – between atria and ventricles Bicuspid valve (left) Tricuspid valve (right) Semilunar valves between ventricle and artery Pulmonary semilunar valve Aortic semilunar valve

13 The Heart: Valves Valves open as blood is pumped through
Held in place by chordae tendineae (“heart strings”) Close to prevent backflow

14 Heart Valves Figure 18.8a, b

15 Heart Valves Figure 18.8c, d

16 Atrioventricular Valve Function
Figure 18.9

17 Semilunar Valve Function
Figure 18.10

18 Operation of Heart Valves
Figure 11.4

19 Valve Pathology Incompetent valve = backflow and repump
Stenosis = stiff= heart workload increased May be replaced Lup Dub Heart Sound

20 The Heart: Associated Great Vessels
Aorta Leaves left ventricle Pulmonary arteries Leave right ventricle Vena cava Enters right atrium Pulmonary veins (four) Enter left atrium

21 Coronary Circulation Blood in the heart chambers does not nourish the myocardium The heart has its own nourishing circulatory system Coronary arteries Cardiac veins Blood empties into the right atrium via the coronary sinus

22 Cardiac Pathology Rapid heart beat = Inadequate blood
= Angina Pectoris

23 Heart Sounds Heart sounds (lub-dup) are associated with closing of heart valves First sound occurs as AV valves close and signifies beginning of systole Second sound occurs when SL valves close at the beginning of ventricular diastole

24 Cardiac Muscle Contraction
Heart muscle: Is stimulated by nerves and is self-excitable (automaticity) Contracts as a unit Has a long (250 ms) absolute refractory period Cardiac muscle contraction is similar to skeletal muscle contraction

25 Heart Contractions Figure 11.5

26 Heart Physiology: Intrinsic Conduction System
Autorhythmic cells: Initiate action potentials Have unstable resting potentials called pacemaker potentials Use calcium influx (rather than sodium) for rising phase of the action potential

27 Pathology of the Heart Damage to AV node = release of ventricles from control = slower heart beat Slower heart beat can lead to fibrillation Fibrillation = lack of blood flow to the heart Tachycardia = more than 100 beats/min Bradychardia = less than 60 beats/min

28 The Heart: Cardiac Cycle
Atria contract simultaneously Atria relax, then ventricles contract Systole = contraction Diastole = relaxation

29 Filling of Heart Chambers – the Cardiac Cycle
Figure 11.6

30 The Heart: Cardiac Output
Cardiac output (CO) Amount of blood pumped by each side of the heart in one minute CO = (heart rate [HR]) x (stroke volume [SV]) Stroke volume Volume of blood pumped by each ventricle in one contraction

31 Cardiac output, cont. CO = HR x SV
5250 ml/min = 75 beats/min x 70 mls/beat Norm = 5000 ml/min Entire blood supply passes through body once per minute. CO varies with demands of the body.

32 Cardiac Output Regulation
Figure 11.7

33 The Heart: Regulation of Heart Rate
Stroke volume usually remains relatively constant Starling’s law of the heart – the more that the cardiac muscle is stretched, the stronger the contraction Changing heart rate is the most common way to change cardiac output

34 Regulation of Heart Rate
Increased heart rate Sympathetic nervous system Crisis Low blood pressure Hormones Epinephrine Thyroxine Exercise Decreased blood volume

35 The Heart: Regulation of Heart Rate
Decreased heart rate Parasympathetic nervous system High blood pressure or blood volume Dereased venous return In Congestive Heart Failure the heart is worn out and pumps weakly. Digitalis works to provide a slow, steady, but stronger beat.

36 Congestive Heart Failure (CHF)
Decline in pumping efficiency of heart Inadequate circulation Progressive, also coronary atherosclerosis, high blood pressure and history of multiple Myocardial Infarctions Left side fails = pulmonary congestion and suffocation Right side fails = peripheral congestion and edema

37 Blood Vessels: The Vascular System
Taking blood to the tissues and back Arteries Arterioles Capillaries Venules Veins

38 The Vascular System Figure 11.8b

39 Blood Vessels: Anatomy
Three layers (tunics) Tunic intima Endothelium Tunic media Smooth muscle Controlled by sympathetic nervous system Tunic externa Mostly fibrous connective tissue

40 Differences Between Blood Vessel Types
Walls of arteries are the thickest Lumens of veins are larger Skeletal muscle “milks” blood in veins toward the heart Walls of capillaries are only one cell layer thick to allow for exchanges between blood and tissue

41 Movement of Blood Through Vessels
Most arterial blood is pumped by the heart Veins use the milking action of muscles to help move blood Figure 11.9

42 Capillary Beds Capillary beds consist of two types of vessels
Vascular shunt – directly connects an arteriole to a venule Figure 11.10

43 Capillary Beds True capillaries – exchange vessels
Oxygen and nutrients cross to cells Carbon dioxide and metabolic waste products cross into blood Figure 11.10

44 Diffusion at Capillary Beds
Figure 11.20

45 Vital Signs Arterial pulse Blood pressure Repiratory Rate
Body Temperature All indicate the efficiency of the system

46 Pulse Pulse – pressure wave of blood
Monitored at “pressure points” where pulse is easily palpated Figure 11.16

47 Blood Pressure Measurements by health professionals are made on the pressure in large arteries Systolic – pressure at the peak of ventricular contraction Diastolic – pressure when ventricles relax Pressure in blood vessels decreases as the distance away from the heart increases

48 Measuring Arterial Blood Pressure
Figure 11.18

49 Blood Pressure: Effects of Factors
Neural factors Autonomic nervous system adjustments (sympathetic division) Renal factors Regulation by altering blood volume Renin – hormonal control

50 Blood Pressure: Effects of Factors
Temperature Heat has a vasodilation effect Cold has a vasoconstricting effect Chemicals Various substances can cause increases or decreases Diet

51 Variations in Blood Pressure
Human normal range is variable Normal 140–110 mm Hg systolic 80–75 mm Hg diastolic Hypotension Low systolic (below 110 mm HG) Often associated with illness Hypertension High systolic (above 140 mm HG) Can be dangerous if it is chronic

52 TERIMA KASIH