Guide 4 Medicos

An artificial heart valve is a device implanted in the heart of a patient with heart valvular disease. When one of the four heart valves malfunctions, the medical choice may be to replace the natural valve with an artificial valve. This requires open-heart surgery.
Valves are integral to the normal physiological functioning of the human heart. Natural heart valves are evolved to forms that perform the functional requirement of inducing unidirectional blood flow through the valve structure from one chamber of the heart to another. Natural heart valves become dysfunctional for a variety of pathological causes. Some pathologies may require complete surgical replacement of the natural heart valve with a heart valve prostheses


            Operations to restore the function of heart valves are commonly performed. They're done to improve the health and vigor of people with heart valve diseases. The surgeon who'll perform the operation is the best person to talk to about specific questions or concerns. He or she can best explain the details of the surgical procedure and recovery period.  People with artificial heart valves are at higher risk for developing an infection of the valve (endocarditis). They are also in the highest risk category for having bad outcomes from endocarditis. The American Heart Association says that people in this highest risk category (others in this category include people who have previously had endocardits, people with certain types of congenital heart disease, and people with a heart transplant who develop heart valve problems) need to take antibiotics before most dental procedures.  However, the association says that people undergoing gastrointestinal or genitourinary procedures do not need to take routine antibiotics solely to prevent endocarditis. 

World Heart Day was created to inform people around the globe that heart disease and stroke are the world’s leading cause of death, claiming 17.2 million lives each year.
Together with its members, the World Heart Federation spreads the news that at least 80% of premature deaths from heart disease and stroke could be avoided if the main risk factors, tobacco, unhealthy diet and physical inactivity, are controlled.

Explore your ear lobes
 
Interactive study game
 
Flash player required..
 

Cardiopulmonary resuscitation (CPR) is an emergency medical procedure for a victim of cardiac arrest or, in some circumstances, respiratory arrest. CPR is performed in hospitals, or in the community by laypersons or by emergency response professionals.

CPR involves physical interventions to create artificial circulation through rhythmic pressing on the patient's chest to manually pump blood through the heart, called chest compressions, and usually also involves the rescuer exhaling into the patient (or using a device to simulate this) to inflate the lungs and pass oxygen in to the blood, called artificial respiration. Some protocols now downplay the importance of the artificial respirations, and focus on the chest compressions only.

CPR is unlikely to restart the heart; its main purpose is to maintain a flow of oxygenated blood to the brain and the heart, thereby delaying tissue death and extending the brief window of opportunity for a successful resuscitation without permanent brain damage. Advanced life support and defibrillation, the administration of an electric shock to the heart, is usually needed for the heart to restart, and this only works for patients in certain heart rhythms, namely ventricular fibrillation or ventricular tachycardia, rather than the 'flat line' asystolic patient although CPR can help bring a patient in to a shockable rhythm.

CPR is generally continued, usually in the presence of advanced life support (such as from a medical team or paramedics), until the patient regains a heart beat (called "return of spontaneous circulation" or "ROSC") or is declared dead.

All India PRE PG MCQ'S...
DOWNLOAD THIS EXCLUSIVE CONTENT(1.56 MB)

Ebola is the term for the viral genus Ebolavirus (EBOV), or for the disease Ebola hemorrhagic fever (EHF). It is named after the Ebola River, where the first recognized outbreak occurred. There are a number of species within the ebolavirus genus, which in turn have a number of specific strains or serotypes. The Zaire virus is the type species, which is also the first discovered and the most lethal.

Electron micrographs show long filaments, characteristic of the Filoviridae viral family. The virus interferes with the endothelial cells lining the interior surface of blood vessels and platelet cells. As the blood vessel walls become damaged and the platelets are unable to coagulate, patients succumb to hypovolemic shock. Ebola is transmitted primarily through bodily fluids and to a limited extent through skin and mucous membrane contact.


Transmission

• The Ebola virus is transmitted by direct contact with the blood, secretions, organs or other body fluids of infected persons.
• Burial ceremonies where mourners have direct contact with the body of the deceased person can play a significant role in the transmission of Ebola.
• The infection of human cases with Ebola virus through the handling of infected chimpanzees, gorillas, and forest antelopes -- both dead and alive -- has been documented in Côte d'Ivoire, the Republic of Congo and Gabon. The transmission of the Ebola Reston strain through the handling of cynomolgus monkeys has also been reported.
• Health care workers have frequently been infected while treating Ebola patients, through close contact without correct infection control precautions and adequate barrier nursing procedures.

Incubation period: two to 21 days.

Symptoms

Ebola is characterized by the sudden onset of fever, intense weakness, muscle pain, headache and sore throat. This is often followed by vomiting, diarrhoea, rash, impaired kidney and liver function, and in some cases, both internal and external bleeding. Laboratory findings show low counts of white blood cells and platelets as well as elevated liver enzymes.

          Myasthenia gravis (MG) is a chronic autoimmune disorder that results in progressive skeletal muscle weakness. Skeletal muscles are primarily muscle fibers that contain bands or striations (striated muscles) that are connected to bone. MG causes rapid fatigue (fatigability) and loss of strength upon exertion that improves after rest.
In early stages, myasthenia gravis primarily affects muscles that control eye movement (extraocular muscles) and those that control facial expression, chewing, and swallowing. If untreated, the disorder may affect muscles that control breathing (respiration), causing acute respiratory failure.
Types
Myasthenia gravis can be classified according to which skeletal muscles are affected. Within a year of onset, approximately 85–90% of patients develop generalized myasthenia gravis, which is characterized by weakness in the trunk, arms, and legs.
About 10–15% of patients have weakness only in muscles that control eye movement. This type is called ocular myasthenia gravis.
Other types of MG include congenital, which is an inherited condition caused by genetic defect, and transient neonatal, which occurs in infants born to mothers who have MG. Congenital MG
Transient neonatal MG is a temporary condition that develops in 10–20% of infants born to mothers who have MG. Transient neonatal MG is caused by circulation of the mother's antibodies through the placenta and it lasts as long as the mother's antibodies remain in the infant (usually a few weeks after birth).
Incidence and Prevalence
Myasthenia gravis affects approximately 2 out of every 100,000 people and can occur at any age. It is most common in women between the ages of 18 and 25. In men, the condition usually develops between 60 and 80 years of age.
develops at or shortly after birth and causes generalized symptoms.
MG usually is caused by a malfunction of the immune system. The causative factor is unknown, but the disorder may have a genetic link. Causes include a genetic defect, which results in congenital MG, and the circulation of maternal antibodies through the placenta, which result in transient neonatal MG.
Acetylcholine (ACh) is a neurotransmitter that is involved in the transfer of information to muscle tissue. In myasthenia gravis, cells that bind to other cells to neutralize or destroy them (called antibodies) destroy acetylcholine receptor sites (AChR) in areas of muscle tissue that receive nerve impulses (called neuromuscular junctions), preventing nerve impulses from reaching the muscles. This results in weakness and rapid fatigue in affected muscles.
MG may be associated with other autoimmune diseases. Patients with family members who suffer from disorders such as rheumatoid arthritis, scleroderma, and lupus may have an increased risk for myasthenia gravis.

The thymus is an organ that produces cells involved in immune responses. It is located below the larynx and above the heart. Approximately 15% of MG patients have a tumor of the thymus (thymoma) and 60–80% have abnormal enlargement (hyperplasia) of the thymus.

Atlas of Human Anatomy - Netter - 2006.pdf

A heart-lung mahcine (also called cardiopulmonary bypass) is usually used during conventional open heart surgery. It helps provide oxygen-rich blood to the brain and other vital organs.
The definition of open heart surgery has become confusing with new procedures being performed on the heart through smaller incisions. There are some new surgical procedures being performed that are done with the heart still beating.
Minimally invasive heart surgery (MIDCAB, OPCAB, RACAB), including robotic-assisted heart surgery, is still considered open heart surgery. However, these procedures are being used in some patients as an alternative to open heart surgery requiring the heart-lung machine.

1) Color-enhanced view of a sperm cell penetrating an egg.

2) An egg being released from a mature follicle on the surface of the ovary.

3) Sperm and egg meet inside the fallopian tube.

4) The moment of conception.

5) (left) Fertilized egg undergoing cell division.
    (right) Cells continue to divide.

6) A fertilized egg implanted high on the endometrial wall.

7) A fetus at eight weeks of pregnancy.

 

Amazing jounney to life

Swine flu{H1N1 flu} is an infection caused by a virus. It's named for a virus that pigs can get. People do not normally get swine flu, but human infections can and do happen. The virus is contagious and can spread from human to human.
Symptoms of swine flu in people are similar to the symptoms of regular human flu and include fever, cough, sore throat, body aches, headache, chills and fatigue.
There are antiviral medicines you can take to prevent or treat swine flu. There is no vaccine available right now to protect against swine flu. You can help prevent the spread of germs that cause respiratory illnesses like influenza by

• Covering your nose and mouth with a tissue when you cough or sneeze. Throw the tissue in the trash after you use it.
• Washing your hands often with soap and water, especially after you cough or sneeze. You can also use alcohol-based hand cleaners.
• Avoiding touching your eyes, nose or mouth. Germs spread this way.
• Trying to avoid close contact with sick people.
• Staying home from work or school if you are sick.