AI News, BOOK REVIEW: 3 Squishy Medical Robots That Are as Soft as You Are
3 Squishy Medical Robots That Are as Soft as You Are
Inside the chests of 41 million people around the world, failing hearts gradually become less effective at the vital task of pumping blood.
In search of a better pumping assistant, an international team of researchers invented a silicone sleeve that slips over the heart’s exterior, thus keeping the robot from contact with flowing blood as it rhythmically squeezes the organ.
The early-stage device uses 14 pneumatic actuators (6 in the concentric layer, 8 in the helical layer), which the team can activate individually by filling them with air, allowing for experimentation with different patterns of contractions.
Human Physiology/The cardiovascular system
The heart's rhythmic contractions occur spontaneously, although the frequency or heart rate can be changed by nervous or hormonal influence such as exercise or the perception of danger.
The endocardium is the innermost lining of the heart which consists of the endothelial cells forming a smooth membrane in places, and a pocked and tribeculated surface in others (mainly the ventricles, or lower pumping chambers).
Failure of the heart to contract properly (for various reasons) is termed heart failure, generally leading to fluid retention, edema, pulmonary edema, renal insufficiency, hepatomegaly, a shortened life expectancy and decreased quality of life.
Atria facilitate circulation primarily by allowing uninterrupted venous flow to the heart, preventing the inertia of interrupted venous flow that would otherwise occur at each ventricular systole.
There are two ventricles: the right ventricle pumps blood into the pulmonary artery which takes the blood through the pulmonary circuit, and the left ventricle pumps blood into the aorta for systemic circulation to the rest of the body.
The inter ventricular septum (ventricular septum, or during development septum inferius) is the thick wall separating the lower chambers (the ventricles) of the heart from one another.
Its upper and posterior part, which separates the aortic vestibule from the lower part of the right atrium and upper part of the right ventricle, is thin and fibrous, and is termed the membranous ventricular septum.
Aortic stenosis occurs in this condition usually in patients in their 40s or 50s, an average of 10 years earlier than in people with normal aortic valves.
For patients who have had rheumatic fever dentists are advised to prophylactically administer antibiotics prior to dental work to prevent bacterial endocarditis that occurs when bacteria from the teeth enter the circulation and attach to damaged heart valves.
The aortic valve is a semilunar valve, but it´s called bicuspid because of it´s regular three 'cusps' or 'semilunar' valves, and is not to be confused with the left atrioventricular valve, which is more commonly called the mitral valve, and is one of the two cuspidal valves.
While it is convenient to describe the flow of the blood through the right side of the heart and then through the left side, it is important to realize that both atria contract at the same time and that both ventricles contract at the same time.
The right pump pumps the blood to the lungs or the pulmonary circulation at the same time that the left pump pumps blood to the rest of the body or the systemic circulation.
It’s proper functioning is responsible for the delivery of oxygen and nutrients to all cells, as well as the removal of carbon dioxide, waste products, maintenance of optimum pH, and the mobility of the elements, proteins and cells, of the immune system.
In developed countries, the two leading causes of death, myocardial infarction and stroke are each direct results of an arterial system that has been slowly and progressively compromised by years of deterioration.
The veins outer walls have the same three layers as the arteries, differing only because there is a lack of smooth muscle in the inner layer and less connective tissue on the outer layer.
Veins are used medically as points of access to the blood stream, permitting the withdrawal of blood specimens (venipuncture) for testing purposes, and enabling the infusion of fluid, electrolytes, nutrition, and medications (intravenous delivery).
venule is a small vein that allows deoxygenated blood to return from the capillary beds to the larger blood veins, except in the pulmonary circuit were the blood is oxygenated.
The double circulatory system of blood flow refers to the separate systems of pulmonary circulation and the systemic circulation in amphibians, birds and mammals (including humans.) In contrast, fishes have a single circulation system.
For instance, the adult human heart consists of two separated pumps, the right side with the right atrium and ventricle (which pumps deoxygenated blood into the pulmonary circulation), and the left side with the left atrium and ventricle (which pumps oxygenated blood into the systemic circulation).
The superior vena cava (SVC) is a large but short vein that carries de-oxygenated blood from the upper half of the body to the heart's right atrium.
Although blood fills the chambers of the heart, the muscle tissue of the heart, or myocardium, is so thick that it requires coronary blood vessels to deliver blood deep into the myocardium.
The coronary arteries are classified as 'end circulation', since they represent the only source of blood supply to the myocardium: there is very little redundant blood supply, which is why blockage of these vessels can be so critical.
• Right coronary artery • Left coronary artery Both of these arteries originate from the beginning (root) of the aorta, immediately above the aortic valve.
As discussed below, the left coronary artery originates from the left aortic sinus, while the right coronary artery originates from the right aortic sinus.
In human anatomy, the hepatic veins are the blood vessels that drain de-oxygenated blood from the liver and blood cleaned by the liver (from the stomach, pancreas, small intestine and colon) into the inferior vena cava.
The body can increase the heart rate in response to a wide variety of conditions in order to increase the cardiac output (the amount of blood ejected by the heart per unit time).
At this point, voltage-gated calcium channels on the cell membrane open and allow calcium ions to pass through, into the main, or interior, of the muscle cell.
The calcium ions bind to the troponin, causing a conformation change, breaking the bond between the protein tropomyosin, to which the troponin is attached, and the myosin binding sites.
This allows the myosin heads to bind to the myosin binding sites on the actin protein filament and contraction results as the myosin heads draw the actin filaments along, are bound by ATP, causing them to release the actin, and return to their original position, breaking down the ATP into ADP and a phosphate group.
Norepinephrine diffuses across the synaptic cleft binds to the β1-adrenoreceptors – G-protein linked receptors, consisting of seven transmembrane domains – shifting their equilibrium towards the active state.
β-adrenoreceptor kinase phosphorylates the calcium ion channels in the sarcolemma, so that calcium ion influx is increased when they are activated by the appropriate transmembrane voltage.
More troponin will be bound and more myosin binding sites cleared [of tropomyosin] so that more myosin heads can be recruited for the contraction and a greater force and speed of contraction results.
When the pressure in the left ventricle drops to below the pressure in the left atrium, the mitral valve opens, and the left ventricle fills with blood that was accumulating in the left atrium.
Likewise, when the pressure in the right ventricle drops below that in the right atrium, the tricuspid valve opens and the right ventricle fills with blood that was in the right atrium The first heart tone, or S1, 'Lub' is caused by the closure of the atrioventricular valves, mitral and tricuspid, at the beginning of ventricular contraction, or systole.
The reduced volume in the right ventricle allows the pulmonic valve to close earlier at the end of ventricular systole, causing P2 to occur earlier, and 'closer' to A2.
A network of nerve fibers coordinates the contraction and relaxation of the cardiac muscle tissue to obtain an efficient, wave-like pumping action of the heart How Stuff Works (The Heart) The heart contains two cardiac pacemakers that spontaneously cause the heart to beat.
If the cardiac muscles just contracted and relaxed randomly at a natural rhythm the cycle would become disordered and the heart would become unable to carry on its function of being a pump.
Sometimes when the heart undergoes great damage to one part of the cardiac muscle or the person incurs an electric shock, the cardiac cycle can become uncoordinated and chaotic.
sinoatrial node (abbreviated SA node or SAN, also called the sinus node) is the impulse generating (pacemaker) tissue located in the right atrium of the heart.
Although all of the heart's cells possess the ability to generate the electrical impulses (or action potentials) that trigger cardiac contraction, the sinoatrial node is what normally initiates it, simply because it generates impulses slightly faster than the other areas with pacemaker potential.
Because cardiac myocytes, like all nerve cells, have refractory periods following contraction during which additional contractions cannot be triggered, their pacemaker potential is overridden by the sinoatrial node.
If the SA node doesn't function, or the impulse generated in the SA node is blocked before it travels down the electrical conduction system, a group of cells further down the heart will become the heart's pacemaker.
Parasympathetic stimulation from the vagal nerves decreases the rate of the AV node by causing the release of acetylcholine at vagal endings which in turn increases the K+ permeability of the cardiac muscle fiber.
In the majority of patients, the SA node receives blood from the right coronary artery, meaning that a myocardial infarction occluding it will cause ischemia in the SA node unless there is a sufficiently good anastomosis from the left coronary artery.
If not, death of the affected cells will stop the SA node from triggering the heartbeat The atrioventricular node (abbreviated AV node) is the tissue between the atria and the ventricles of the heart, which conducts the normal electrical impulse from the atria to the ventricles.
The blood supply of the AV node is from a branch of the right coronary artery in 85% to 90% of individuals, and from a branch of the left circumflex artery in 10% to 15% of individuals.
The bundle of HIS is a collection of heart muscle cells specialized for electrical conduction that transmits the electrical impulses from the AV node (located between the atria and the ventricles) to the point of the apex of the fascicular branches.
The bundle of HIS branches into the three bundle branches: the right left anterior and left posterior bundle branches that run along the intraventricular septum.
It is extremely important for these nodes to exist as they ensure the correct control and co-ordination of the heart and cardiac cycle and make sure all the contractions remain within the correct sequence and in sync.
During the ventricular contraction portion of the cardiac cycle, the Purkinje fibers carry the contraction impulse from the left and right bundle branches to the myocardium of the ventricles.
This causes the muscle tissue of the ventricles to contract and force blood out of the heart — either to the pulmonary circulation (from the right ventricle) or to the systemic circulation (from the left ventricle).
In a hospital during VF the monitor would make a sound and alert the doctors to treat the fibrillation by passing a huge current through the chest wall and shocking the heart out of its fibrillation.
This causes the cardiac muscle to stop completely for 5 seconds and when it begins to beat again the cardiac cycle would have resumed to normal and the heart will be beating in a controlled manner again.
Circus movement occurs when an impulse begins in one part of the heart muscle and spreads in a circuitous pathway through the heart then returns to the originally excited muscle and 're-enters' it to stimulate it once more.
The graph can show the heart's rate and rhythm, it can detect enlargement of the heart, decreased blood flow, or the presence of current or past heart attacks.
Unless indicated otherwise, blood pressure refers to systemic arterial blood pressure, i.e., the pressure in the large arteries delivering blood to body parts other than the lungs, such as the brachial artery (in the arm).
 Hypertension often has an insidious or un-noticed onset and is sometimes called the silent killer because stretching of the arteries causes microscopic tears in the arterial wall and accelerates degenerative changes.
Persistent hypertension is one of the risk factors for strokes, heart attacks, heart failure and arterial aneurysm, and is a leading cause of chronic renal failure Atherosclerosis is a disease affecting the arterial blood vessel.
It most commonly becomes seriously symptomatic when interfering with the coronary circulation supplying the heart or cerebral circulation supplying the brain, and is considered the most important underlying cause of strokes, heart attacks, various heart diseases including congestive heart failure and most cardiovascular diseases in general.
Heparin and warfarin are often used to inhibit the formation and growth of existing blood clots, thereby allowing the body to shrink and dissolve the blood clots through normal methods.
An embolism occurs when an object (the embolus) migrates from one part of the body (through circulation) and causes a blockage (occlusion) of a blood vessel in another part of the body.
Blood clots form the most common embolic material by far: other possible embolic materials include fat globules (a fat embolism), air bubbles (an air embolism), septic emboli (containing pus and bacteria), or amniotic fluid.
The term 'brain attack' is starting to come into use in the United States for stroke, just as the term 'heart attack' is used for myocardial infarction, where a cutoff of blood causes necrosis to the tissue of the heart.
One of the initial drugs used to dissolve clots was streptokinase, although its use creates a possibility of clot destruction throughout the entire body, leading to serious hemorrhage.
Acute myocardial infarction (AMI or MI), commonly known as a heart attack, A heart attack occurs when the supply of blood and oxygen to an area of heart muscle is blocked, usually by a clot in a coronary artery.
Often, this blockage leads to arrhythmias (irregular heartbeat or rhythm) that cause a severe decrease in the pumping function of the heart and may bring about sudden death.
It is the leading cause of death for both men and women all over the world Angina Pectoris is chest pain due to ischemia (a lack of blood and hence oxygen supply) of the heart muscle, generally due to obstruction or spasm of the coronary arteries (the heart's blood vessels).
Coronary artery bypass surgery, coronary artery bypass graft surgery and heart bypass are surgical procedures performed on patients with coronary artery disease for the relief of angina and possible improved heart muscle function.
Veins or arteries from elsewhere in the patient's body are grafted from the aorta to the coronary arteries, bypassing coronary artery narrowing caused by atherosclerosis and improves the blood supply to the myocardium (heart muscle).
Congestive heart failure (CHF), also called congestive cardiac failure (CCF) or just heart failure, is a condition that can result from any structural or functional cardiac disorder that impairs the ability of the heart to fill with or pump a sufficient amount of blood throughout the body.
Because not all patients have volume overload at the time of initial or subsequent evaluation, the term 'heart failure' is preferred over the older term 'congestive heart failure'.
A wire is passed from the femoral artery in the leg or the radial artery in the arm up to the diseased coronary artery, to beyond the area of the coronary artery that is being worked upon.
At the same time, if an expandable wire mesh tube (stent) was on the balloon, then the stent will be implanted (left behind) to support the new stretched open position of the artery from the inside.
However, when the valve becomes defective, blood is forced into the superficial veins by the action of the muscle pump (which normally aids return of blood to the heart by compressing the deep veins).
Eight defects are more common than all others and make up 80% of all congenital heart diseases, whereas the remaining 20% consist of many independently infrequent conditions or combinations of several defects.
The pulmonary circuit carries blood through the lungs where gas exchange occurs and the systemic system transports blood to all parts of the body where exchange with tissue fluid takes place.
There are three main ways that they work together to maintain homeostasis: the lymphatic system receives the excess tissue fluid and returns it to the bloodstream, lacteal take fat molecules from the intestinal villi and transport them to the bloodstream and both systems work together to defend the body against disease.The lymphatic system can create white blood cells that fight off disease and infections.
Recent research suggests that taking a small dose of aspirin daily may help prevent a heart attack (because aspirin inhibits platelet clumping). •
To put this in perspective, the Earth's circumference is 40,075.02 kilometres and 60,000 miles is around 96,000 km - so your blood vessels would go twice around the world and still have some to spare!
The heart muscle becomes less efficient with age, and there is a decrease in both maximum cardiac output and heart rate, although resting levels may be more than adequate.
Atherosclerosis is the deposition of cholesterol on and in the walls of the arteries, which decreases blood flow and forms rough surfaces that may cause intravascular clot formation High blood pressure (hypertension) causes the left ventricle to work harder.
In the ebb (shock) phase there is Inadequate circulation, decreased insulin level, decreased oxygen consumption, hypothermia (low body temperature), hypovolemia (low blood volume), and hypotension (low blood pressure).
In the flow phase there is increased levels of catecholamine, glucocorticoids, and glucagons, normal or elevated insulin levels, catabolic (breakdown), hyperglycemic (high blood sugar), increased oxygen consumption/respiratory rate, hyperthermia (high body temperature) fever sets in, hypermetabolism, increased insulin resistance, increased cardiac output.
Excitation occurs through the SA node to the AV node if there are abnormalities or drug interference that malfunctions the AV node the ventricles will not receive the initiating stimuli and the autorhythmic cells in the bundle branches begin to initiate actions on their own rate becoming the pacemakers for the ventricles.
AV bundle (located in the intraventricular septum between the two ventricles that go in two directions right and left bundle branches that leave the septum to enter the walls of both ventricle) •
Bundle Branches (the branching off the septum to the walls of the ventricles that run into the purkinje fibers that then make contact with ventricular myocardial cells to spread the impulse to the rest of the ventricles) •
Hormonal control of blood pressure An example of the ever expanding technology for the heart is best described in this story: In 1955, when I was five years old, I first learned by my family physician that I had a heart murmur and that it would eventually need attention.
This time, unlike the others, I was told that because of new machine technology, Dr. Kitzes found that I had aortic stenosis, which is a narrowing of the valve passage by build-up of plaque due to the valve being malformed at birth.
After asking me about my symptoms, which were fatigue, weakness, asthmatic symptoms, as well as ashen skin color and dizziness, he informed me of how serious my condition was and the only salvation was immediate open-heart surgery to replace the aortic valve.
Our goal in this chapter is to take you by the hand and lead you through each part of the cardiovascular system, so that you too may learn and come to respect the greatness of this blood pumping machine we all call the heart.
Decreased blood flow also known as ischemia is dangerous to any tissue but brain tissue is even more vulnerable, mainly due to the high rate of its metabolic reactions.
natriuretic peptide: Produced in the atria of the heart, it increases urinary excretion of sodium which causes water loss which in turn the viscosity of the blood is lowered and in turn lowers the blood pressure. Atrioventricular
Vascular Accident (CVA): Also known as a stroke, is a rapidly developing loss of a part of brain function or loss of consciousness due to an interruption in the blood supply to all or part of the brain.
Veins: blood vessels that drain de-oxygenated blood from the liver and blood cleaned by the liver (from the stomach, pancreas, small intestine and colon) into the inferior vena cava Hypertension
The heart sits within a fluid-filled cavity called the pericardial cavity.
Pericardium is a type of serous membrane that produces serous fluid to lubricate the heart and prevent friction between the ever beating heart and its surrounding organs.
The pericardium has 2 layers—a visceral layer that covers the outside of the heart and a parietal layer that forms a sac around the outside of the pericardial cavity.
The right side of the heart has less myocardium in its walls than the left side because the left side has to pump blood through the entire body while the right side only has to pump to the lungs.
The right side of the heart maintains pulmonary circulation to the nearby lungs while the left side of the heart pumps blood all the way to the extremities of the body in the systemic circulatory loop.
About 1% of the cardiac muscle cells in the heart are responsible for forming the conduction system that sets the pace for the rest of the cardiac muscle cells.
The AV bundle splits into left and right branches in the interventricular septum and continues running through the septum until they reach the apex of the heart.
Branching off from the left and right bundle branches are many Purkinje fibers that carry the signal to the walls of the ventricles, stimulating the cardiac muscle cells to contract in a coordinated manner to efficiently pump blood out of the heart.
At any given time the chambers of the heart may found in one of two states: The cardiac cycle includes all of the events that take place during one heartbeat.
From the aorta, blood enters into systemic circulation throughout the body tissues until it returns to the heart via the vena cava and the cycle repeats.
The first part of the wave, called the P wave, is a small increase in voltage of about 0.1 mV that corresponds to the depolarization of the atria during atrial systole.
The next part of the EKG wave is the QRS complex which features a small drop in voltage (Q) a large voltage peak (R) and another small drop in voltage (S).
Variations in the waveform and distance between the waves of the EKG can be used clinically to diagnose the effects of heart attacks, congenital heart problems, and electrolyte imbalances.
The equation used to find cardiac output is: CO = Stroke Volume x Heart Rate Stroke volume is the amount of blood pumped into the aorta during each ventricular systole, usually measured in milliliters.
If you're seeing this message, it means we're having trouble loading external resources on our website.
If you're behind a web filter, please make sure that the domains *.kastatic.org and *.kasandbox.org are unblocked.
The heart is a chambered muscular organ that pumps blood received from the veins into the arteries, thereby maintaining the flow of blood through the entire circulatory system.
The heart is constructed of a special kind of muscle called the myocardium or cardiac muscle, and is enclosed in a double-layered, membranous sac known as the pericardium.
Oxygenated blood returns from the lungs to the left atrium and enters the left ventricle, which contracts, forcing the blood into the aorta, from which it is distributed throughout the body.
cardia = heart), the middle myocardium ( myo - = muscle), and the inner endocardium ( endo - = within, inward).
The parietal layer is continuous with the visceral layer of the serous pericardium or epicardium , which lies on the heart and is considered a part of the heart wall. Myocardium The
The myocardium's elongated, circular, and spiral arranged networks of cardiac muscle cells, called bundles, squeeze blood through the heart in the proper directions: inferiorly through the atria and superiorly through the ventricles. Endocardium The
Learn Heart Anatomy: Vessels, Valves, and Chambers (oh my!)
The heart wall is composed of three distinct layers: the epicardium (outermost layer), the myocardium (middle layer, comprised of muscular fibers), and the endocardium (innermost layer).
the pulmonary valve controls the flow of blood into the pulmonary trunk, and the aortic valve into the aorta.
the coronary arteries supply blood to the heart tissue while the veins move oxygenated blood from the heart tissue into the right atrium.
myocardial infarction, or heart attack, occurs when blood flow to the heart tissue via the coronary arteries is obstructed (usually due to plaque buildup).
If oxygenated blood can't reach the tissue, the tissue will die, weakening the heart and leaving behind scarring.
If an artery is blocked, it may warrant coronary bypass surgery, in which a section of a healthy vessel is used to create a new pathway, detouring blood from the blocked artery into the new vessel, allowing oxygenated blood to flow.
The conduction system is a system controlled by the autonomic nervous system, which delivers electrical impulses that cause the cardiac muscles to contract, or beat.
The conduction system is comprised of a series of nodes and fiber bundles, and each electrical impulse travels the same path.
The sinoatrial node is where the impulse initiates and then travels to the atrioventricular node (where it pauses), then further to the bundle of His.
- On Thursday, September 19, 2019
Robotic heart sleeve supports failing hearts
RESTRICTIONS: NONE For story suggestions please contact email@example.com Harvard researchers have developed a soft robotic sleeve that can replicate normal heart muscle movements...
Electrical system of the heart | Circulatory system physiology | NCLEX-RN | Khan Academy
See where the pacemaker cells start the electrical wave of depolarization, and how it gets all the way to the ventricles of the heart. Rishi is a pediatric infectious disease physician and...
Vox Machina Go to Hell | Critical Role RPG Episode 91
Check out our store for official Critical Role merch: Catch Critical Role live Thursdays at 7PM PT on Alpha and Twitch: Alpha: Twitch:
Congestive heart failure (CHF) - systolic, diastolic, left side, right side, & symptoms
What is congestive heart failure (CHF)? CHF is when the heart isn't able to pump enough blood to meet the body's demands, which leads to congestion—or fluid buildup—in various parts of...
Talks Machina: Campaign Wrap-up
Explore the adventures of Vox Machina one last time with the cast of Critical Role! The cast answers your burning questions -- from Kraghammer to the Whitestone to Vasselheim (and everywhere...
The Circulation Improving Leg Wraps.
These leg wraps inflate and deflate to improve circulation, soothe sore muscles, and reduce swelling in your lower extremities. Similar to hospital compression boots that stimulate circulation...
Young Money - Senile ft. Tyga, Nicki Minaj, Lil Wayne
Young Money feat. Tyga, Nicki Minaj, and Lil Wayne - Senile (Explicit)
Thorium is an abundant material which can be transformed into massive quantities of energy. To do so efficiently requires a very different nuclear reactor than the..
Mind the Matrix FULL FILM EN/NL/ES/DE
NOTE 1: The makers of this film do not encourage the viewer to drink Ayahuasca. This film is not about this medicine plant. It is only mentioned in the beginning of this film whereby the narrator...
Viktor Schauberger - Die Natur kapieren und kopieren (Dokumentarfilm, 2008)
Der erste Film über Viktor Schaubergers Lebenswerk. Eine umfassende Bestandsaufnahme historischer Fakten, aktueller Forschungsergebnisse und vielfältiger Umsetzungen in Natur und Technik....