Cardiovascular System: Heart and Blood Vessels

• The Cardiovascular System is in charge of the transport. It delivers nutrients and oxygen to all tissues. It transports waste products and oxygen from cells to organs for external elimination

• The blood being pumped by the heart circulates through the circulatory or cardiovascular system, composed of blood vessels

• This system comprises the heart and blood vessels, forming a closed circuit through which blood distributes from the heart to the entire body and back

• The heart pumps and draws blood, facilitating circulation throughout the body via blood vessels

• It is situated in the thoracic cavity, in the mediastinum, behind the sternum and in front of the dorsal vertebrae 5a to 7a. It weighs approximately 300 grams in a healthy adult

• The apex faces the left hip, resting on the diaphragm, as the base points towards the right shoulder, sitting below the second rib

• The mediastinum is located in the thoracic cavity between the pleural cavities, bordered inferiorly by the diaphragm

• The mediastinum contains the heart, trachea, bronchi, esophagus, aorta, superior and inferior vena cava, lymphatic vessels, ganglions, and nerves

Heart anatomy

• The cardiac wall is made up of three layers

• The endocardium is the inner layer lining the cardiac cavities, continuous with the tissue of blood vessels

• The myocardium is the middle and thickest layer, made of cardiac muscle tissue

• The epicardium, or outer layer, is part of the serous pericardium and is made of connective tissue and epithelium

• The heart can suffer inflammatory alterations like endocarditis, myocarditis, and pericarditis

• The pericardium, a double-membrane sac of connective tissue, envelops the heart, protecting it and enabling free movement

• It protects the heart against friction

• Two layers of the pericardium:

• The parietal layer is the outer layer that attaches to the serous fibers of the great vessels, protecting and anchoring the heart to surrounding structures like the diaphragm and sternum

• The visceral layer or epicardium is attached to the myocardium

• In between the visceral and parietal layers lies a virtual space called the pericardial cavity, which contains pericardial fluid

• The serous fluid reduces friction between both layers, enabling their movement during myocardial motion

• Cavities and cardiac valves. The heart divides into two halves by an oblique longitudinal partition called the septum

• One half, either the right or the left, consists of an auricle or atrium and a ventricle

• Auricles or atria are superior cavities, right and left, that receive blood entering through the veins. They are separated by the interauricular septum

• Ventricles are inferior cavities responsible for pumping blood that exits through the arteries. They are separated by the interventricular septum, which is thicker than the interauricular one

• Two grooves distinguish the heart externally. The transverse or coronary sulcus surrounds the heart, separating the auricles from the ventricles

• The longitudinal sulcus determines the limit between the ventricles, with two parts: anterior and posterior interventricular

• The thickness of the cardiac cavities relies on the muscular layer and the need for blood propulsion

• The auricles are thinner than the ventricles. The right ventricle has thinner walls than the left

• The right atrium receives venous blood from the whole body through the superior and inferior vena cava and the coronary sinus

• It communicates with the right ventricle through the tricuspid valve

• The right ventricle receives venous blood from the right atrium and pumps it into the pulmonary arteries through the semilunar pulmonary valve, preventing backflow

• The pulmonary artery transports this blood to the lungs for oxygenation

• The left atrium receives oxygenated blood from the lungs through the four pulmonary veins

• It communicates with the left ventricle through the mitral or bicuspid valve

• The left ventricle contains thicker walls than the right, and pumps oxygenated blood towards the aorta through the aortic semilunar valve, preventing backflow

• The aorta distributes oxygenated blood throughout the body

• Cardiac valves regulate blood flow and prevent backflow

• Atrioventricular valves (AV). Located between the atria and ventricles

• The tricuspid valve on the right contains three membranes or leaflets

• The mitral or bicuspid valve on the left contains two membranes or leaflets

• The AV valves prevent backflow into the atria when ventricles contract

• The AV valves function with tendinous cords anchored to papillary muscles

• Semilunar valves (SL) are located between the ventricles and arteries

• The pulmonary valve regulates passage to the pulmonary arteries

• The aortic valve regulates passage to the aorta

• Semilunar valves contain three valves that close to prevent blood backflow toward the heart

• The cardiac valves prevent backflow of blood and ensure its flow in one direction

• There are Atrioventricular Valves (AV) and Semilunar Valves (SL):

• Atrioventricular Valves (AV) exist between the auricles and ventricles.

• Tricuspid: Right, with three membranes.

• Mitral or bicuspid: Left, with two membranes.

• Prevent backflow to the auricles when the ventricles contract.

• They are held together by tendinous cords and papillary muscles.

• Semilunar Valves (SL) exist between ventricles and arteries:

• Pulmonary: in the right ventricle

• Aortic: In the left ventricle

• There are three valves that open when expelling blood and close to prevent its return.

• The heart muscle is miogenic and creates its own electrical impulses to contract

• The heart creates and transmits electrical impulses that control its contraction

• The components of this system are:

• The sinoatrial (SA) node, which is the natural pacemaker, is situated in the right atrium.

• The atrioventricular (AV) node delays the impulse before sending it to the ventricles

• The Bundle of His conducts the impulse along the interventricular septum

• Purkinje fibers distribute the electrical signal through the ventricles, causing their contraction

• System of vascularization. The coronary sinus collects venous blood from the heart and takes it to the right auricle

• Coronary arteries originate from the ascending aorta that irrigates the heart, and the circumflex artery and left anterior descending artery come from the left coronary artery

• Blood Vessels are a network that transports blood through the body, including arteries, arterioles, veins, venules, and capillaries

• Arteries carry blood from the heart to the tissues and are elastic, dividing into smaller branches

• The aorta originates from the left ventricle and transports oxygenated blood

• The Pulmonary artery originates from the right ventricle, taking blood to the lungs to oxygenate

Layers of the arteries

• Tunica externa (adventitia) has elastic and collagen fibers

• Tunica media contains smooth muscle that permits contraction and relaxation

• Tunica intima is an endothelial layer coating the arterial lumen

• Arterioles are the smallest arteries, regulating blood flow before reaching the capillaries

• Veins and venules transport blood from the organs and tissues back to the heart

Blood vessels characteristics

• Vessels contain similar walls to the arteries, but with less muscular thickness

• Blood vessels contain valves which impede the venous blood,s return

• Blood vessels can store great volumes of blood

• Venous return is able to flow in one direction towards the heart thanks to:

• Venous valves prevent the bloods venous return

• Muscular contractions impulse the blood

• The thorax's negative pressure generates a suction effect

• There are two major Venous Systems:

• The peripheral venous system transports carboxigenated blood from the tissues to the heart

• The pulmonary venous system transports oxygenated blood from the lungs back to the the heart.

• Venules are small veins that connect capillaries to the larger venous system

• Capillaries are the finest blood vessels (1-30 µm in diameter) connecting arterioles and venules (~100 µm in diameter)

• Capillaries contain single endothelial cell layers, making them fragile

• Capillaries contain characteristics such as closing and repairing rapidly thanks to platelets and coagulation factors

• Capillaries are not present in the cornea, crystalline lens, or cartilage.

• The primary function of Capillaries is to exchange oxygen, nutrients, CO₂, and wastes. The density of the capilllary network varies per organ.

• The Cardiac Cycle refers to a series of electric and physical events that start from the end of a ventrical contraction until starting its next cycle

• These phases of the cardiac cycle are:

• Diastole (relaxation): the phase of the cycle when ventricles and auricles are fulfilling.

• Systole (contraction): phase of expelling blood towards the heart.

Phases of the cardiac cycle

• Ventricular Diastole (0.5 s) begins after the ventricular Systole
• The ventricular pressure decreases and the aortic and pulmonar sigmoideas (aortic and pulmonar) close.
• The trivalvular mitral valves open, filling the ventricles. • - Ventricular Systole (0.3s)
• A nervous impulse is sent from the AV node, through His’ bundle- Fibers of Purkinje
• The ventricular pressure augmentates and the trivalvular and mitral valves close
• The sigmoide valves expulse blood towards the arteries
• The cycle finishes when the arterial and ventricular pressure even out.

• - Auricular Diastole (0.7 s)

• The Auricles fulfill with blood through hollow and pulmonar veins.

• The cycle coincides with the ventricular diastole during 0.4s • - Auricular Systole (0.1 s)

• This cycle initiates through the sinoauricular node (SA)

• Auricles are set in motion, the AV valves open, fulfilling the ventricles.

• The sigmoide valves remain closed.

• Blood circulation refers to moving blood through the body from the heart, through the vasal system, and the blood,s return movement.

• In humans these two movement are:

• Both, the deoxigenated and oxigenated vasal system are circulated twice through the heart

• Complete. The deoxigenated parts do not mix with oxigenated parts

• Closed the blood is always contained in vasal tissue.

Types of blood circulation:

• Great Circulation (Systemic - Peripheric)

• It travel through the body, transport oxygen and nutrients to cells

• This starts with the left ventricle followed by the aorta-arteries, and capillaries (here the gas components and nutrients are exchanged).

• Return: Veins- hollow veins located on the upper and lower body- Auricle, right.

• Subtype: Hepatic-door circulation

• Vasal system is splint-gastric and mesenteric. and goes to portal veins- liver- then its hepatic which then devolves on a hollow

• Subtype: Coronary Circulation

• Hollow coronaries- deliver oxigeneated blood to the heart.

• From here returns the coronial seno, an auricle.

• Lower circulation (pulmonar)

• Transports deoxigenated blood to the pulmonaries where oxigenation takes place.

• The cycle starts where the right hallow- pulmonar arthery. pulmones where the gas exchange

• Devolvement from pulmonar veins to the left.

• Fetal circulation - oxigen blood and nutrients arrives to the feutus from the mother trhough umbilical

• Residual materials are dissolved through unmbilical arteries.

• Cerebral circulation

• Charotidian Artheries: Carries oxigenated blood towards the brain

• Vena yugular. Devolve the blood to the hearth,

• Contains baro receptors and receptors that quimio-receptors in order to regular arterial pressure and composition in chemical make.

• Cardiac sounds: "Lubb" Closing the attrioventricular valves. "Dupp" Closing the sigmoide valves

• Lower circulation, circulation contorl and cardio functions: This transport deoxigenated blood from heart to lungs to Oxigenate, devolving to the left auricle.

• Circulation Contorl: its regulated by the autonomic vasal system which can simpatize or parasimpatize, It assures the liquids continual flow around the blood , distributing and augmenting them in accordance to their needs.

• Arterial pression: depends, on the artheial width and liquids viscose density..

• Cardiac Expenditure: the volume of expulsaed heart measured by its beat during one minute. It calculates aproximatedly around 5 liters per min.

• ECG: Measures the electrical activity. Wth it the waves that reflect auricular and ventricule repolarizacion can be evaluated.

Functions of the cardio vasal system:

• Transportation, this drives oxygen, nutrients, hormones and removes deshechons and CO2.
• Defence protect against infection with white globes and anti bodies
• Homeostesis regulate temperature, blood pressure and maintain an equilibrium.

Pathologies: heart Failure

• An inability of the hearth to pump blood efficiently

• Causes: rythim failure - Valve issues, miocardial issues etc

• -inflamation of the pericardio which is linked to infection - infarcs or medications.

• Endocarditis inflammacion interna

• Shocks serious vasal issues with an imbabalce of high demand and low oxigene, These can be hipobulemic neurogen septic or cardiogenic.

• HTA hipertension arterial rise in aterial presion without an organic cause the 95% of cases in link to stress and alcohol.

• Aterosclerosis hardeness on the artierias with a lose in elasticity

• Aterosclerosis- hardness due to gromas obstructing, producing infarct, The proceses causes damage due to high levels of clorestol- that damaged tissues causing inflamation.

• Angina de pecho, reduction in arteriaflow this can even cause pain.

• Miocardial hardeness , necrosis due to obstruction of the ateria

• Tromboangetis- inflamation of blood vessels arterias in the extremities

• Aneorismas Pathological dilatation , commony in aorta

• Trombosis venosa : formation of coaguls in vasal thissues commonyl in infeiror tissues

• Varaicosis : expansion of blood vessel commonly in the lower limps . This is linked to problems with the vasal valves and cause blood to acculmate in the blood valves.

• Respiratory Apparatus is a process that involves various systems besides the digestive system.

  • Respiratory apparatus: exchanges gases, capturing O2 and eliminating CO2.
  • Circulatory System: transports nutrients, O2 and waste products.
  • Excretory apparatus: eliminates metabolic waste products

• One of the key processes of nutrition is respiration, which is divided into:

  • External Respiration: gas exchange between the organism and the environment.
  • Cellular respiration: occurs in the mitochondria and generates energy.

• Gaseous exchange occurs in three phases:

  • Ventilation: the entry and exit of air into the body.
  • External respiration: gas exchange in the lungs.
  • Internal respiration: use of O2 in the cell and production of CO2..

• Functions of the respiratory system: filter, heat and humidify the air, transport gases, exchange O2 and CO2 with the blood, ventilate the lungs, regulate body pH, detect odors

• The respiratory system is formed by organs that allow the exchange of gases, carrying O2 to the tissues and eliminating CO2.

• Main organs: Upper respiratory tract: Nose and pharynx.

• Lower respiratory tract: Larynx, trachea, bronchi and lungs.

• Alveoli: Place where gaseous exchange occurs..

Nose anatomy

• connects the respiratory system with the exterior. It is divided into the external nose and nasal cavities (located in the roof of the mouth)

• This has odor receptors in the yellow pituitary, which Detects chemicals in the air and doesn't sens oxygen or Carbon Dioxide

• Nasal Cavities, Turbinates and Paranasal Sinuses: The nasal cavities are separated by the nasal septum and covered by a mucosa with microscopic cilia and cilia. These structures filter suspended particles in the air before it reaches the respiratory tract.

• The part that communicates with the outside is called the vestibule..

• The nasal turbinates are mucous-covered bone structures located inside each nasal cavity. Usually, there are three turbinates per cavity: superior, middle and inferior. Its main function is regulate the temperature and humidity of the inspired air, as well as filtering impurities and acting as a barrier against infectious agents.

• The paranasal sinuses are hollow cavities located in the frontal, sphenoid, ethmoid and upper maxillary bones.

• 8 paranasal sinuses that drain into the nose. Main functions: condition inspired air the filtration of impurities, lighten the weight of the skull and act as a box of resonance for the voice, favoring phonation..

pharynx anatomy

Is a muscular tube 13 cm long that connects the mouth and nose with the digestive and respiratory. Contains tonsils with immune function, whose inflammation causes anginas..

• Allows the passage of air and food and participates in phonation. It may be related to Otitis media, due to infections in the Eustachian tube.

Larynx anatomy

• Organ that communicates the pharynx with the trachea. It is located in the anterior part of the neck, between the 4th and 6th cervical vertebra. It is made up of 9 cartilages, among them the thyroid, which forms the "Adam's apple".

• It is divided into three parts: Vestibule or supraglotis (upper part). Glottis, where the vocal cords. And Subglottis, which connects with the trachea.

• The muscles of the larynx help in the breathing and phonation. The voice is produced by the vibration of the air when passing through the cords Vocals. The epiglottis prevents food from entering the larynx when swallowing.

• At rest, it allows air to pass however, when swallowing, it folds and covers the glottis. Coughing is a reflex that expels foreign elements from the larynx and does not occur in unconscious people.

• Vocal Cords: They are located in the larynx. Superior: False cords, do not produce sound.

• Lower: True vocal cords, responsible for the production of sound. The air passes through them, causing them to vibrate and produce sound.

• Trachea: 11 cm tube that connects the larynx

• With the bronchi. Formed by cartilage rings that prevent its collapse. Lined by ciliated mucosa which aids in breathing.

• Bronchi: Located at the bottom of the trachea, dividing into main bronchi:

• Right: Short, wide (2 cm), vertical.

• Left: Long, narrow (1.5 cm). • Formed by incomplete rings before entering the lungs and complete inside them. Covered by ciliated mucosa inside..

• They branch into (Secondary) lobar bronchi: 3 the right lung and 2 the left lung. The bronchi tertiaries They continue branching until they form the bronchioles and alveolar ducts, which end in the alveolar sacs, where gas exchange is achieved.

• Structure similar to an inverted tree, known as arbre bronchial. Surrounded by smooth muscle, controlled by the autonomic nervous system, which regulates air flow. It’s mainly function is to carry air to the lungs and back to the outside..

• In the alveoli, the O2 and CO2 exchange occurs (hematosis).

• Lungs: Function and Location: The lungs are the main organs of respiration, located in the cavity thoracic, except in the mediastinum.

lungs structure

• Apex: Conical upper part.

• Base: Diaphragmatic face. Costal face: Lateral.

• Internal face (mediastinal): Concave, contains the hilum for the entry of bronchi, vessels and nerves.

• Pleura: Double membrane that covers the lungs:

• Parietal pleura: Reviews the thoracic wall, mediastinum and diaphragm.

• Visceral pleura: Attached to the surface of the lung.

• Pleural cavity: Space with pleural fluid that facilitates sliding during the breathing.

• Lobes and Segments: Right lung: 3 lobes (superior, middle, inferior) and 10 segments.

• Left lung: 2 lobes (superior and inferior) and 10 segments.

• Gaseous exchange: The bronchi branch into air sacs with pulmonary alveoli, where it takes place gas exchange (O2 and CO2) through the respiratory membrane.

Lungs function

Structure: The lungs allow the capture and distribution of air, facilitating the gas exchange.

• They are composed of the bronchial tree, blood network and elastic connective tissue, which provides protection and allows passive retraction during exhalation. Weigh approximately 1.5 kg and are soft and spongy.

• Physiology of Respiration: Respiration involves the transport of oxygen (O2) from the atmosphere to the alveoli and the elimination of carbon dioxide (CO2) from the alveoli to the external.

• Ambient air contains 78% nitrogen, 21% oxygen and the remaining 1% consists of carbon dioxide and other gases.

• Ventilation is the key in breathing, being the mechanic phase, and the exchange of gases between oxygen and carbon in the blood as a regulation.

• Pulmonary: Ventilation (Mechanical Phase of Respiration): Pulmonary ventilation is the process of air renewal in the lungs, allowing the passage of air in and out of the lungs due to the pressure difference between inside and outside.

• The two phase of the process are:

• Inspiration (inhalation):

• Occurs when pulmonary pressure is lower than atmospheric pressure.

• Involves contraction of the diaphragm and intercostal muscles.

• The diaphragm contracts and descends, increasing the volume of the thoracic cavity and allowing air to flow into the lungs. Is an active process and, in case of forced in inspiration, also involved the accessory muscles (scalenes, sternocleidomastoids, pectoralis minor).

• Spirometry (exhalation):

• Passive process where pulmonary pressure is higher than atmospheric, which expels the air outwards.

• The muscles of the chest relax, the thoracic volume decreases and the air is expelled.

• In forced exhalations, the abdominal muscles help to expel more air.

Types of breathing

• Thoractic, is what mostly is use on the intercostal muscles. Abdominal- Is deeper and provides relaxation to the person improving the venous circulation.

Intercambio de Gases (Hematosis):

• The pressure of gases occurs between pulmonaries and blood cells between Oxigen (O2) and carbon dioxode, This process relies on the defference of parcial presure for each different gases
• O2: The parcial opresion is superior in alveuos, this causes an alto oxygen flow from el alveoulls to the sangue oxigen blood
• CO2: The partial presion is greater in lungs than in alveoullo were it is expulsions out wards

• - Once the blood is oxigenates flows to hallow veins - pulomnaries devolving outwars throughout all tissues and structures inside that orge

• Gases in Blood and Cellular Respiration

• Transporte de Oxigeno (O2)

• 97% of oxugen ties itself with hemoglovin to get trasnportated trough erythrocites. to form a the oxihemoglovin . One molecule is able transporter for O2

• oxgino es trasnporated trough the the isues with cells due an alto oxigen to lower concetrations -

• Transporte de Dioxido de Caborn (CO2)

• The CO2 intercahnges similary but inversely. due an presiosn cell concetroin to the stream of sangre

• Mairita es CO2 transportates to de Hemoglobina with carboxilhemobina .

• a part is deisolving inside platmatic plasma. CO2 regresa al corazón derecho,, luego a los pulmones donde is expludsado en la aspiracion

• Curva de Dsolacion A high PO2 - Hemoglobina saturates oxygen - when lower de hemoglobina is freeding oxygen is 30%

• Monoxidio de carbon (CO) a lot of CCo2 will prebent this , ocacionandd falat of oxigen. a tint is high levels of rojos Ceresa and skin

• Thereatment usual is the respaircion con O2 puro: an inodro gas is dangrous

• Controls of Respiration : The Respiaricon is principalmete conctrolado par el Sistema Nervous Central which is ajustando and is is esd e las demadnaos y el control s el nervio el frenito - is a nerve that allows intercostales This e

• Contro Respaotioro and en los y la putenrica This centra coorindado and efecionios respaorcios the voluentions pulnomar . This centers are principal

• The Control apmesto regula of spriacions Profunda. Centori Nuomotaxico de Resptoria Bulbaure- conrtala The base and respartcion

• Vs atutontacion this can b es controllada o alnadear o conctrlola - The rest and contorl adpative para evade danaos

• Regulacion de la Resipirion por Esimulo Quimico: la vulntelaciones estan influenciao that sensaes in a tranoc enco

• Sensores

• The dirocets of CO2

• Sensons resptoirs y reben a la conctoris o deicando the hyboxaio - cuando el promero is sucficente

• Esfectors . 13 :1

• The el conotrla del en el sangreesat reaccions

• Las condicon de las conction de la sangre a del el sangre

• • The aclaosis resparitoria se produce cuando haay disminicon de CO2

• Los stinas de la alcalsiasr paritoria incluetm horgues y marest Conrol de Bronquios

• El conortaola el es regulatdoo . La de sprionetaria mide los mvolumess - and resultandos dependecion en la ededa

• Volumens pumares clave. The capaidad de pt Volumen corriente de wvw