heart & it’s rhythmical contractions dr. wasif haq
TRANSCRIPT
![Page 1: Heart & It’s Rhythmical Contractions Dr. Wasif Haq](https://reader035.vdocument.in/reader035/viewer/2022062321/56649f325503460f94c4ef1c/html5/thumbnails/1.jpg)
Heart & It’s Rhythmical Contractions
Dr. Wasif Haq
![Page 2: Heart & It’s Rhythmical Contractions Dr. Wasif Haq](https://reader035.vdocument.in/reader035/viewer/2022062321/56649f325503460f94c4ef1c/html5/thumbnails/2.jpg)
General Anatomy of Heart• Myogenic organ, involved in blood
circulation.• Pericardial sac encloses the heart.• Three layers; Epicardium, Myocardium &
Endocardium.• 4 chambers; 2 receiving & 2 discharging
chambers.• Right side- Pulmonary blood flow.• Left side- Systemic blood flow.
![Page 3: Heart & It’s Rhythmical Contractions Dr. Wasif Haq](https://reader035.vdocument.in/reader035/viewer/2022062321/56649f325503460f94c4ef1c/html5/thumbnails/3.jpg)
Chamber & Valvular Anatomy• Right atrium collects deoxygenated blood
from Vena Cavas.• Tricuspid valve= Right atrium & right
ventricle, pushes blood towards ventricle.• Pulmonary valves= Right ventricle &
pulmonary arteries.• Left atrium receives oxygenated blood
from lungs.• Bicuspid valves/ Mitral= Left atrium &
ventricle.• Aortic valve= Left ventricle & aorta.
![Page 4: Heart & It’s Rhythmical Contractions Dr. Wasif Haq](https://reader035.vdocument.in/reader035/viewer/2022062321/56649f325503460f94c4ef1c/html5/thumbnails/4.jpg)
![Page 5: Heart & It’s Rhythmical Contractions Dr. Wasif Haq](https://reader035.vdocument.in/reader035/viewer/2022062321/56649f325503460f94c4ef1c/html5/thumbnails/5.jpg)
Aspects of Cardiac Muscles• Involuntary, striated muscle fibers.
• 1. Sarcomere: Contractile unit, thick (Myosin) & thin (Actin, Troponin & Tropomyosin) filaments.
• 2. Intercalated disk: Junctions occurring at end of cardiac cells, contraction as single unit.
• 3. Gap junctions: Present at intercalated disk, rapid electrical impulse transmission.
• 4. Mitochondria: Abundant quantity.• 5. T-tubules: Carry action potential to inside
of cell, well developed in ventricles.• 6. Sarcoplasmic reticulum: Storage of Ca++
ions.
![Page 6: Heart & It’s Rhythmical Contractions Dr. Wasif Haq](https://reader035.vdocument.in/reader035/viewer/2022062321/56649f325503460f94c4ef1c/html5/thumbnails/6.jpg)
Syncytium• Syncytium= Multi-nucleate cells resulting
from multiple cell fusion into an aggregate mass.
• Cardiac cells are interconnected, rapid excitation.
• Two types: a. Atrial syncytium, b. Ventricular syncytium.
• No transmission between two syncytiums because of separation by fibrous tissue except at A.V. bundle.
![Page 7: Heart & It’s Rhythmical Contractions Dr. Wasif Haq](https://reader035.vdocument.in/reader035/viewer/2022062321/56649f325503460f94c4ef1c/html5/thumbnails/7.jpg)
![Page 8: Heart & It’s Rhythmical Contractions Dr. Wasif Haq](https://reader035.vdocument.in/reader035/viewer/2022062321/56649f325503460f94c4ef1c/html5/thumbnails/8.jpg)
![Page 9: Heart & It’s Rhythmical Contractions Dr. Wasif Haq](https://reader035.vdocument.in/reader035/viewer/2022062321/56649f325503460f94c4ef1c/html5/thumbnails/9.jpg)
Rhythmical Contraction• S.A. Node
• Internodal Pathways
• A.V. Node
• A.V. bundle (Bundle of His)
• Bundle branches (2 left & 1 right)
• Purkinjee fibers.
![Page 10: Heart & It’s Rhythmical Contractions Dr. Wasif Haq](https://reader035.vdocument.in/reader035/viewer/2022062321/56649f325503460f94c4ef1c/html5/thumbnails/10.jpg)
![Page 11: Heart & It’s Rhythmical Contractions Dr. Wasif Haq](https://reader035.vdocument.in/reader035/viewer/2022062321/56649f325503460f94c4ef1c/html5/thumbnails/11.jpg)
Sinoatrial Node• Pacemaker.• Normal, rhythmical impulse generation.• Location: Superior, posterolateral wall of
right atrium, lateral to superior vena cava opening.
• Directly connected to atrial muscle fibers.
![Page 12: Heart & It’s Rhythmical Contractions Dr. Wasif Haq](https://reader035.vdocument.in/reader035/viewer/2022062321/56649f325503460f94c4ef1c/html5/thumbnails/12.jpg)
Internodal pathway• Anterior, middle & posterior internodal
pathways.• Impulse reaches A.V. node through
internodal pathway.
![Page 13: Heart & It’s Rhythmical Contractions Dr. Wasif Haq](https://reader035.vdocument.in/reader035/viewer/2022062321/56649f325503460f94c4ef1c/html5/thumbnails/13.jpg)
A.V. Node• Delay of impulse conduction from atria to
ventricles.• Allowing for ventricular filling before
ventricular contraction.• Delay occurs due to lesser gap junctions
causing greater resistance to conduction.
![Page 14: Heart & It’s Rhythmical Contractions Dr. Wasif Haq](https://reader035.vdocument.in/reader035/viewer/2022062321/56649f325503460f94c4ef1c/html5/thumbnails/14.jpg)
A.V. Bundle/ Bundle of His• Fibrous insulation all over atria &
ventricles except at A.V. bundle.• Very rapid conduction.• Impulse unidirectional only.
![Page 15: Heart & It’s Rhythmical Contractions Dr. Wasif Haq](https://reader035.vdocument.in/reader035/viewer/2022062321/56649f325503460f94c4ef1c/html5/thumbnails/15.jpg)
Bundle Branches• The bundle of His branches into the three
bundle branches: the right, left anterior and left posterior bundle branches .
• The bundles give rise to thin filaments known as Purkinje fibers.
![Page 16: Heart & It’s Rhythmical Contractions Dr. Wasif Haq](https://reader035.vdocument.in/reader035/viewer/2022062321/56649f325503460f94c4ef1c/html5/thumbnails/16.jpg)
Purkinjee Fibers• Rapid transmission of action potential by
Purkinjee fibers.• Few myofibrils, little tendency to contract.• Impulse from Purkinjee fibers travels to
ventricular muscle mass by ventricular muscle fibers themselves.
![Page 17: Heart & It’s Rhythmical Contractions Dr. Wasif Haq](https://reader035.vdocument.in/reader035/viewer/2022062321/56649f325503460f94c4ef1c/html5/thumbnails/17.jpg)
Take Home MessageIf having wisdom makes human proud, arrogant and ignorant towards his Creator then such wisdom is certainly and surely foolishness.
http://coolbluez.t15.org