chapter 18: cardiovascular system: the heart
DESCRIPTION
Chapter 18: Cardiovascular System: The Heart. Dr. Norman E. Shumway – performed the first heart transplant in the United States in 1968. The 54-year-old recipient, whose heart had been damaged by virus infection, survived 15 days following surgery. - PowerPoint PPT PresentationTRANSCRIPT
Chapter 18:
Cardiovascular System:The Heart
Dr. Norman E. Shumway – performed the first heart transplant in the United States in 1968.
The 54-year-old recipient, whose heart had been damaged by virus infection, survived 15
days following surgery.
Human Anatomy and Physiology, 7eby Elaine Marieb & Katja Hoehn
Copyright © 2007 Pearson Education, Inc.,publishing as Benjamin Cummings.
Figure 18.3: The circular and spiral arrangement of cardiac muscle bundles in the myocardium of the heart, p. 680.
Cardiacmusclebundles
Human Anatomy and Physiology, 7eby Elaine Marieb & Katja Hoehn
Copyright © 2007 Pearson Education, Inc.,publishing as Benjamin Cummings.
Figure 18.4a: Gross anatomy of the heart, p. 681.
(a)
Right atrium
Anteriorinterventricularartery
Right ventricle
Aortic arch(fat covered)
Left auricle ofleft atrium
Apex of heart(left ventricle)
Pulmonary trunk
Human Anatomy and Physiology, 7eby Elaine Marieb & Katja Hoehn
Copyright © 2007 Pearson Education, Inc.,publishing as Benjamin Cummings.
Figure 18.4b: Gross anatomy of the heart, p. 681.
(b)
BrachiocephalictrunkSuperiorvena cava
Rightpulmonary artery
AscendingaortaPulmonary trunk
Rightpulmonary veinsRight atriumRight coronaryartery (in coronarysulcus)Anteriorcardiac veinRight ventricleMarginal arterySmall cardiac veinInferiorvena cava
Left commoncarotid arteryLeftsubclavian arteryAortic arch
Ligamentumarteriosum
Left pulmonary artery
Left atrium
Auricle
CircumflexarteryLeft coronaryartery (in coronarysulcus)
Anteriorinterventricular artery(in anteriorinterventricular sulcus)
Great cardiac vein
Apex
Left pulmonary veins
Left ventricle
Human Anatomy and Physiology, 7eby Elaine Marieb & Katja Hoehn
Copyright © 2007 Pearson Education, Inc.,publishing as Benjamin Cummings.
Figure 18.4d: Gross anatomy of the heart, p. 682.
(d)
Superiorvena cavaRightpulmonary artery
Rightpulmonary veins
Right atrium
Right coronaryartery (in coronarysulcus)
Right ventricle
Coronary sinus
Middle cardiac vein
Left pulmonary artery
Left atrium
Auricleof left atrium
Left ventricle
Posterior veinof left ventricle
Posteriorinterventricular artery(in posteriorinterventricular sulcus)
Great cardiac vein
Apex
Leftpulmonary veins
Inferiorvena cava
Aorta
Human Anatomy and Physiology, 7eby Elaine Marieb & Katja Hoehn
Copyright © 2007 Pearson Education, Inc.,publishing as Benjamin Cummings.
Figure 18.4e: Gross anatomy of the heart, p. 683.
(e)
Superior vena cava
Rightpulmonary arteryPulmonary trunk
Right atriumRightpulmonary veinsFossaovalisPectinatemuscles
TricuspidvalveRight ventricle
ChordaetendineaeTrabeculaecarneaeInferiorvena cava
Aorta
Leftpulmonary arteryLeft atriumLeftpulmonary veins
Pulmonaryvalve
Aorticvalve
Mitral (bicuspid) valve
Left ventricle
PapillarymuscleInterventricularseptumMyocardium
VisceralpericardiumEndocardium
Human Anatomy and Physiology, 7eby Elaine Marieb & Katja Hoehn
Copyright © 2007 Pearson Education, Inc.,publishing as Benjamin Cummings.
Figure 18.5: The systemic and pulmonary circuits, p. 684.
Capillary bedsof lungs wheregas exchangeoccurs
Capillarybeds of allbody tissueswhere gasexchangeoccurs
Pulmonaryveins
Pulmonaryarteries
Pulmonary Circuit
Systemic Circuit
Aorta and branches
Leftatrium
Heart
LeftventricleRight
atrium
Rightventricle
Venaecavae
Key:
= Oxygen-rich, CO2-poor blood= Oxygen-poor, CO2-rich blood
Human Anatomy and Physiology, 7eby Elaine Marieb & Katja Hoehn
Copyright © 2007 Pearson Education, Inc.,publishing as Benjamin Cummings.
Figure 18.6: Anatomical differences in right and left ventricles, p. 685.
Rightventricle
Leftventricle
Muscularinterventricularseptum
Human Anatomy and Physiology, 7eby Elaine Marieb & Katja Hoehn
Copyright © 2007 Pearson Education, Inc.,publishing as Benjamin Cummings.
Figure 18.7: Coronary circulation, p. 685.
(a) (b)
Rightventricle
Rightcoronaryartery
Rightatrium
Marginalartery
Posteriorinterventricularartery
Anteriorinterventricularartery
Circumflexartery
Leftcoronaryartery
Aorta
Anastomosis(junction ofvessels)
Leftventricle
Superiorvena cava
Left atrium
Pulmonarytrunk
Superiorvena cava
Anteriorcardiacveins
Small cardiac vein Middle cardiac vein
Greatcardiacvein
Coronarysinus
Human Anatomy and Physiology, 7eby Elaine Marieb & Katja Hoehn
Copyright © 2007 Pearson Education, Inc.,publishing as Benjamin Cummings.
Figure 18.11: Microscopic anatomy of cardiac muscle, p. 690.
Intercalated disc
Nucleus
Nucleus
Nucleus
Desmosome
Desmosome
Gap junctions
Intercalated discs
Sarcolemma
I bandA band
Cardiac muscle cell
Cardiac muscle cell
Sarcolemma
Z disc
Mitochondrion
Mitochondrion
T tubule
Sarcoplasmicreticulum
I band
(b)
(a)
William Einthoven – invented the electrocardiograph and awarded the nobel
prize in 1924
Human Anatomy and Physiology, 7eby Elaine Marieb & Katja Hoehn
Copyright © 2007 Pearson Education, Inc.,publishing as Benjamin Cummings.
Figure 18.16: An electrocardiogram tracing (lead I), p. 696.
Sinoatrialnode
Atrioventricularnode
QRS complex
Atrialdepolarization
Ventriculardepolarization
Ventricularrepolarization
P-QInterval S-T
Segment
P
R
Q
S
T
Q-TInterval
Time (s) 0 0.2 0.4 0.6 0.8
Human Anatomy and Physiology, 7eby Elaine Marieb & Katja Hoehn
Copyright © 2007 Pearson Education, Inc.,publishing as Benjamin Cummings.
Figure 18.17: The sequence of excitation of the heart related to the deflection waves of an ECG tracing, p. 696.
SA node generates impulse;atrial excitation begins
Impulse delayedat AV node
Impulse passes toheart apex; ventricularexcitation begins
Ventricular excitationcomplete
SA nodeAV node Purkinje
fibersBundlebranches
Human Anatomy and Physiology, 7eby Elaine Marieb & Katja Hoehn
Copyright © 2007 Pearson Education, Inc.,publishing as Benjamin Cummings.
Figure 18.19: Areas of the thoracic surface where the heart sounds can be best detected, p. 697.
Sounds of tricuspid valve are typically heard inright sternal margin of 5th intercostal space;variations include over sternum or over left sternal margin in 5th intercostal space.
Sounds of aortic valve areheard in 2nd intercostal space atright sternal margin.
Sounds of pulmonary valve are heard in 2nd intercostalspace at left sternal margin.
Sounds of mitral valve areheard over heart apex, in 5thintercostal space in line with middle of clavicle.
Human Anatomy and Physiology, 7eby Elaine Marieb & Katja Hoehn
Copyright © 2007 Pearson Education, Inc.,publishing as Benjamin Cummings.
Figure 18.24: Development of the human heart during week 4, p. 705.
Heart twists
Arterial end
Venous end
Atrium
Ventricle
AortaSuperiorvena cava
Inferiorvena cava
DuctusarteriosusPulmonarytrunkForamenovale
Ventricle
Endothelialtubes beginto fuse Arterial end
Venous end
Ventricle
Tubularheart
4a
4
3
21
(d)
(e)
(a) (b) (c)
Human Anatomy and Physiology, 7eby Elaine Marieb & Katja Hoehn
Copyright © 2007 Pearson Education, Inc.,publishing as Benjamin Cummings.
Figure 18.25: Three examples of congenital heart defects, p. 708.
Occurs inabout 1 in every500 births
Occurs inabout 1 in every1500 births
Narrowedaorta
Occurs inabout 1 in every2000 births
Ventricular septal defect.The superior part of the inter-ventricular septum fails to form;thus, blood mixes betweenthe two ventricles, but becausethe left ventricle is stronger, more blood is shunted fromleft to right.
(a) Coarctation of the aorta.A part of the aorta is narrowed,increasing the workload onthe left ventricle.
(b) Tetralogy of Fallot. Multiple defects (tetra = four): Pulmonary trunk too narrow and pulmonary valve stenosed, resulting in a hypertrophied right ventricle; ventricular septal defect; aorta opens from both ventricles; wall of right ventricle thickened from overwork.
(c)