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How much does heart valve replacement surgery cost in South Africa

Compare The Cost Of Aortic Heart Valve Replacement

Compare the cost of aortic heart valve replacement abroad. Aortic valve replacement is a cardiac surgery procedure in which a patient's failing aortic valve is replaced with an alternate healthy valve. The aortic valve can be affected by a range of diseases; the valve can either become leaky or partially blocked Those inserted through open-heart surgery cost about R20 000. Catheter-based valves cost about R300 000 in the private sector without hospital and procedure fees. He said UCT was trying to adapt to.. How much you can expect to pay out of pocket for heart valve replacement, including what people paid. For patients covered by health insurance, out-of-pocket costs typically consist of doctor visit copays, prescription drug copays and coinsurance of 10%-50% or more, which probably would reach the yearly out-of-pocket maximum. Valve replacement surgery typically is covered by health insurance

Aortic valve replacement can be done either with open heart surgery, or by using a catheter (PAVR - percutaneous aortic valve replacement). The replacement valves used in the procedure are either natural (biologic) or artificial (mechanical). Days admitted : 1-3 days at the intensive care unit. The total time in the hospital is usually between. Artificial heart implantation. In 2001, an artificial heart, the Berlin heart, was implanted into a patient for the first time in South Africa.The procedure was performed at Netcare Christiaan Barnard Memorial Hospital in Cape Town, and was performed on a patient with heart failure, who was awaiting a heart transplant

Made in SA: plastic heart parts - News that Connects South

  1. imally invasive CABG) is a technique where the incision is smaller, reducing some of the risks of this surgery
  2. Latin America: heart valve replacement cost 2019, by country Brazil: number of cardiovascular surgeons 2013-2018 Cost comparison for selected surgeries 2007: U.S. and Asi
  3. National Library of Medicine. Cost per patient was $14,469 for mitral valve replacement, and $11,606 for mitral valve repair. At East Carolina University, surgeons say that the hospital gets paid a fixed fee of $25,000 for the total cost of each heart-valve repair regardless of whether robotics are used
  4. How much you can expect to pay out of pocket for heart bypass surgery, including what people paid. For patients covered by health insurance, out-of-pocket costs typically consist of doctor visit copays, prescription drug copays and coinsurance of 10%-50% or more, which could easily reach the yearly out-of-pocket maximum. Heart bypass surgery typically is covered by health insurance when.
  5. How much does aortic valve replacement surgery cost? If you're having the procedure done in the United States without any insurance, plan on spending at least $70,000 to $125,000 for more than one valve to be replaced. For one valve alone, it can vary anywhere from $20,000 to $40,000 per
  6. During the procedure, your surgeon removes your damaged valve and sews a new valve in its place. The two main types of replacement valves are: Tissue/biological valves. These can come from humans or animals. Mechanical valves. These are made of materials such as metal, carbon or synthetics

Transcatheter aortic valve replacement (TAVR) is a minimally invasive procedure to replace a narrowed aortic valve that fails to open properly (aortic valve stenosis). In this procedure, doctors insert a catheter in your leg or chest and guide it to your heart. A replacement valve is inserted through the catheter and guided to your heart Compare the cost of cardiac pacemaker insertion abroad. A pacemaker (or artificial pacemaker, so as not to be confused with the heart's natural pacemaker) is a medical device that uses electrical impulses, delivered by electrodes contacting the heart muscles, to regulate the beating of the heart The most expensive three. The most expensive surgery that the NHS does is very complex intracranial procedures, 18 years and under, with CC Score 12+ (brain surgery on children) £40,936.

Cost of Heart Valve Replacement - 2021 Healthcare Cost

Heart valve surgery is a procedure to treat heart valve disease. Heart valve disease involves at least one of the four heart valves not working properly. Heart valves keep blood flowing in the correct direction through your heart. The four valves are the mitral valve, tricuspid valve, pulmonary valve and aortic valve If your doctor says you need surgery to replace your heart's aortic valve, this is why you need it and what you can expect from the procedure and recovery Single bypass surgery averages around $15,000 to $30,000 for each graft, but costs may differ between geographic regions and hospital. A single bypass graft costs roughly $10,000 in India, and $18,500 in Singapore. In South Africa, the procedure costs roughly $12,80

The heart has four valves that keep blood moving in the correct direction around the body. Oxygen-rich blood flows from the lungs and through the mitral valve into the heart's main pumping chamber, the left ventricle. When the heart squeezes, the mitral valve closes so blood does not flow backwards into the lungs The risk of dying from an aortic valve replacement is around 1 to 3%, although this risk is much smaller than that of leaving severe aortic valve problems untreated. Most people who survive surgery have a life expectancy close to normal After surgery and heart valve replacement procedure immediately, the people often practice basic type of self-care. In addition, the doctors encourage them to get up very soon, take deep breath and resume daily activities which include drinking, eating and walking Severe aortic stenosis is one of the most common cardiovascular disease processes and is projected to affect 1.4 million people over the age of 75 in the United States by 2025. 1 Surgical aortic valve replacement (SAVR) has traditionally been the standard treatment for severe aortic stenosis, but over the last 10 years, transcatheter aortic valve replacement (TAVR) has rapidly emerged as an.

The surgeon may also remove a small portion of the diseased heart muscle or artery in order to better view the heart function. Aortic valve replacement surgery, sometimes called a mitral valve prolapse or MVR surgery, is one of the treatments used to treat Aortic Vasculitis. This treatment involves removing part or all of the affected heart muscle Factors Affecting Recovery from Heart Valve Surgery. Written by American Heart Association editorial staff and reviewed by science and medicine advisers. See our editorial policies and staff. Last Reviewed: May 12, 2020. Heart Valve Disease About Heart Valves.

Valve Replacement in Johannesburg, South Afric

  1. PROCEDURE: 2021 PRICES: Abdoplasty: Tummy Tuck: R 76 100.00: Bicoronal Forehead Lift: R 44 650.00: Bilateral Breast Augmentation: Boobs: R 63 700.00: Bilateral Breast.
  2. According to the latest Cardiac Surgery market study by iData Research, over 182,000 heart valve replacements are performed every year in the United States. These replacements are one of the most common procedures performed in the cardiac surgery market, and they make up nearly a quarter of the total procedure volume
  3. There's good news if you or someone you love needs a new heart valve and you have been told open-heart surgery is too risky. People with severe aortic stenosis may be good candidates for a less invasive replacement called a transcatheter aortic valve implantation (TAVI), also called transcatheter aortic valve replacement (TAVR)
  4. imally invasive surgery, including transcatheter heart valve replacement, is poised to surge the market
  5. ation before being approved for the use of Zephyr valves
  6. Aortic Valve Replacement is a surgery to replace and repair the main valve that controls correct blood flow through the heart. A weak or improperly working valve means the heart has to work harder.

Cardiac Facilities and Services - Netcare Hospital

The time duration for which patient is required to stay in the hospital after the heart valve replacement surgery entirely depends on patient's condition and recovery speed. On an average, a patient is asked to stay in the hospital for around 7 days to up to maximum 3 weeks or until their heart starts to function normally Recovering from open-heart surgery involves physical and emotional healing. The recovery process uses emotional and physical energy. If you feel upset or emotional in the weeks after your operation, don't worry — this is a normal reaction Heart surgery can help to maintain and prolong life by: restoring blood supply to the heart by opening - or replacing - blocked coronary arteries. stretching, repairing or replacing a damaged heart valve. correcting or regulating an abnormal heart rhythm. Apart from emergency situations, it's important you're prepared for surgery and know. Asan Medical centre is the largest hospital in Korea attracting an increasing number of patients every year. Situated across an area of 574,700 m2 the hospital has 2700+ beds attracting 11,862 outpatients and 2557 in-patients on an average per day. The hospital is one of the preferred centres for critical procedures like cardiac, organ. Heart valve replacement surgery is generally considered effective, and you should feel some benefits of your new prosthetic heart valve almost immediately. However, surgery is not without risks, and complications are possible. You need to know about them so you can alert your doctor if you notice symptoms

Heart Bypass Surgery in South Africa - Health-Tourism

  1. The term miracle has also been applied to a relatively new heart disease treatment called transcatheter aortic valve replacement (TAVR). for open heart surgery. TAVR may cost as much.
  2. The situation in Africa . A review of valvular heart disease (rheumatic and non-rheumatic) in Africa [3] shows that the focus remains on rheumatic heart disease. In Western nations valvular heart disease affects the older patient and is slow in onset. In Africa it is the young who tend to be affected and the disease progresses much more rapidly
  3. A valve replacement surgery (aortic valve surgery) is replacing a damaged valve in your heart with a mechanical valve (made from synthetic materials) or a tissue valve (usually taken from pig, cow, or human donors). A new valve will relieve the strain and aims to ease symptoms such as breathlessness and chest pain due to angina
  4. Complications, sometimes leading to repeated surgery or even death, may be associated with heart valve replacement. Discuss your personal situation with your doctor to ensure you understand the risks, benefits, and possible complications associated with heart valve replacement surgery
  5. Heart valve surgery. Heart valve surgery is an operation to repair or replace leaking, narrowed or infected valves. It may ease the symptoms of heart valve disease and prevent permanent damage to your heart. Heart valve surgery is usually open-heart surgery. This means a cut is made to the breastbone to reach the heart
  6. Valvular heart disease is a form of heart disease that occurs when one or more of the heart's four valves don't function properly. Valve replacement surgery may be an option if the valves of.

Get an estimate on how much a typical heart stent surgery costs using our Surgery Cost & Hospital Procedure Calculator Find, research and contact over 1,200 heart valve surgeons in more than 30 countries around the world at HeartValveSurgery.co Cardiac Surgery is the treatment performed on the heart to resolve any disorder. Cardiac surgeries are generally complicated and it is equally crucial to choose the right surgeon. Indian Healthguru is a medical value provider in India having association with the best cardiac surgeons and hospitals, providing world-class treatment at affordable. Double Valve Replacement Surgery Fortis Hospital Shalimar Bagh, India Heart Double Valve Replacement Valid Till: 31st Oct 2021 . Benefits. City Tour for 2 . Airport Transfers . MORE . Cape Town, South Africa Explore more hospitals in South Africa . 24 + Top Medical Destinations Valve movement after deployment, blockage or disruption of blood flow through the heart, need for additional heart surgery and possible removal of the Edwards SAPIEN 3 Ultra and SAPIEN 3 valves, a blood clot that requires treatment, damage to the valve (e.g., wear, breakage, recurring aortic stenosis), nonstructural valve dysfunction (e.g.

The research, published in the Archives of Internal Medicine, found that heart bypass surgery, a common procedure, costs an average of $10,373 in Canada, compared with $20,673 in the United States can then repair or replace the damaged mitral valve. Once inside the heart, the repair or replacement technique is carried out in exactly the same way as the sternotomy operation. Benefits of the minimally invasive approach • The recovery period is much quicker. Usually after about three weeks you will feel better and be able to undertak This replacement enables proper blood flow again and reduces the threat of a heart attack. A bypass can be done to replace one, two or even three blocked arteries. When three arteries are replaced, the procedure is known as a triple bypass surgery. The number of arteries or veins being replaced in the surgery is the number mentioned in the surgery Traditional Aortic Valve Surgery. During traditional aortic valve surgery, a surgeon makes a 6- to 8-inch incision down the center of your sternum, and part or all of the sternum (breastbone) is divided to provide direct access to your heart. The surgeon then repairs or replaces your abnormal heart valve or valves

Heart bypass costs select countries 2019 Statist

Valve replacement surgery is high-risk for people who have a failing left ventricle and who have had a heart attack. About 5 or less out of 100 people who have valve surgery die. footnote 2 If you have severe aortic valve regurgitation or stenosis, the risks of not replacing the valve may be greater than the risks of surgery unless you have. Heart Bypass. Up to $130,000. $24,000. 70-80%. Heart Valve Replacement. Up to $160,000. $15,000. 80-90%. Angioplasty. Up to $57,000. $9,000. 70-80%. Hip Replacement. Up to $43,000. $12,000. (Clinica Biblica is ranked in the top 10 for this specific surgery). While the cost is still drastically lower than in USA or Canada, they can still dip. Step 2. A small tube with a camera, called a bronchoscope, will be inserted into your lungs through your nose or mouth. Step 3. During the 30- to 60-minute procedure your doctor will place between 3 to 5 Zephyr Valves in the airways. Step 4. You will stay in the hospital for a minimum of 3 nights for observation. Step 5 Zephyr Valve Procedure Cons. As with any surgery, this procedure also comes with some risks. One risk associated with Zephyr Valve procedures is that they can cause a temporary worsening of emphysema symptoms after surgery. Some patients may also develop pneumonia or increased mucus production and wheezing after the procedure Mitral Valve Center. If you would like to find out whether you are a candidate for robot assisted mitral valve surgery or learn more about minimally invasive heart surgery, contact us or call the Miller Family Heart, Vascular & Thoracic Institute Resource & Information Nurse at 216.445.9288 or toll-free at 866.289.6911

A Zephyr Valve Treating Doctor can perform eligibility tests and provide treatment if you are eligible. An Assessment Center can perform eligibility tests and then, if you are eligible, you can visit a Zephyr Valve treating doctor for the procedure. Find the nearest location to be evaluated Heart bypass surgery is a complicated procedure that involves a significant amount of preparation and recovery time. Occasionally, someone must undergo emergency heart bypass surgery, but most of. 305-585-4HRT. Community physicians can refer patients in need of specialized cardiac or thoracic care to Jackson Heart Institute for a comprehensive evaluation. Call our physician line at 305-585-4HRT or fax to 305-355-1560. Our multidisciplinary team is your partner throughout every step of the patient journey

Structural Heart Devices Market Overview: Global Structural Heart Devices Market size was valued at $6,006 million in 2015, and is expected to reach $12,076 million by 2022, supported by a CAGR of 10.5% during the forecast period 2016 - 2022. A structural heart disease is a non-coronary defect of the heart, thus not affecting the blood vessels in the heart If you need surgery or a procedure, you may be able to estimate how much you'll have to pay. You can: Ask the doctor, hospital, or facility how much you'll have to pay for the surgery and any care afterward. If you're an outpatient, you may have a choice between an ambulatory surgical center and a hospital outpatient department The first successful penis transplant was performed in South Africa in 2014, involving a 21-year-old recipient who lost his penis due to a failed circumcision. After the 2014 procedure proved successful, other transplants were performed, one in the U.S. in 2016 and another in South Africa in 2017 Open heart surgery is an operation to repair a fault or damage in the heart. It is a major operation during which the surgeon will open the chest to access the heart. This surgery will require a.

Heart Surgery Costs & Expenses - Heart Valve Surger

  1. imally invasive procedure approved for treating patients with clinically significant mitral regurgitation due to either (a) a deteriorated mitral valve but the patient is at very high risk for surgery, or (b) an improperly functioning mitral valve resulting from heart failure, with poor pumping of the blood by an.
  2. Patient's pay. Acromioplasty (remove some shoulder bone surface) $500. $500. Adenoid removal. $350. $280. Ankle replacement. $1,400
  3. Finance options. We offer a range of payment plans from 0% APR interest free credit over 10 months to higher interest bearing loans at 9.9% APR if you wish to spread your payments over 12 months or more (up to 60 months). The loan can be personalised based on how much you'd like to pay per month, how long you want the payments to be spread.

A heart transplant is the replacement of a person's heart with a healthy donor's heart. The most common complication of heart transplant surgery is organ rejection. There are not enough donor hearts available for everyone who needs a heart transplant. The high cost of a heart transplant is also a factor in patients being able to afford or have a health insurer pay for the procedure Price list/Cost of common surgeries in Nigeria. Myomectomy (fibroid removal surgery) - #200,000 to #350,000 Naira. Mastectomy (Breast removal surgery) - #230,000 to #280,000 Naira. Cataract surgery- #400,000 to #1 million Naira. Sometimes some NGOs and state government may sponsor free cataract surgery The average hospital stay runs $11,700 with Medicare ($13,600) and other insurance ($12,600) paying top dollar and the uninsured ($9,300) and Medicaid ($9,800) paying the least. Those are alarming figures, especially for families with limited budgets or no insurance. It is not surprising that 60%-65% of all bankruptcies are related to. Cost: $929,600 2 . Like a double lung transplant, the wait list can be long and it's still very expensive to merely replace a single lung. Coupling a lung and a heart transplant together is. Surgery in other countries is almost always less expensive and in some places, the cost is significantly less. In some areas, the costs are 75% less than what the procedure would cost domestically. Surgeons from outside the U.S. have begun to actively seek patients who are willing to travel for the surgery that they need, promoting themselves.

Cost of Heart Bypass Surgery - 2021 Healthcare Cost

FLOMATIC CORPORATION 15 Pruyn's Island Drive Glens Falls, NY 12801 USA. PHONE: 1-800-833-2040 INTERNATIONAL CALLERS: 518-761-9797 FAX: 1-800-314-315 Heart Valve Surgery. There are four valves in the heart.These are called the mitral valve, aortic valve, tricuspid valve and pulmonic valve. These are described in more detail in this linked article. Heart valve repair and replacement is conventionally performed with the use of the heart lung machine Turns out, a heart stent isn't always beneficial for everyone—the stents may be something you want to avoid altogether. Here's what the experts say. The post 10 Things You Should Know Before.

How Much Does Aortic Valve Replacement Surgery Cost

Interpretation Note Wait times have been impacted by reduced service delivery during the COVID-19 pandemic. Under the Chief Medical Officer of Health's Directive #2 and Memorandum, from March 19 to May 26, 2020, health service providers and health service organizations including hospitals were directed to reduce elective surgeries and other non-emergency clinical activities to preserve. Hello i had mitral valve replacement surgery in February 2020 got a mechanical valve put in and currently have afib also and its control by warfarin i got a echocardiogram done 8weeks after surgery results were normal and i had injection fraction of 58% currently am not driving right now but have cleared to go back to my non driving job do need. Below you will find a list of our low cost pet surgery prices. In an ideal world, a total hip replacement would be the gold standard of care like in people, but since pets walk on 4 legs instead of 2, they can still walk easily without stable hip joints. An FHO involves removing the ball of the upper leg bone that connects with the hip bone. 1958. Lowell Edwards dreams of creating an artificial heart. 1960. First successful mitral valve replacement using the Starr-Edwards Silastic ball valve. 1961. Edwards Laboratories established in Orange County, CA. 1963. Development of the Fogarty embolectomy catheter spawns Edwards' Vascular business. 1970 In the United States, a knee replacement cost 35 thousand U.S. dollars, while in Israel the average cost is 25 thousand U.S. dollars. At the other end of the scale, a knee replacement costs 6.6.

Heart valve replacement HC

The average price of a knee replacement in the U.S. is higher than in comparable countries with available data The average price of a knee replacement in the U.S. was $28,184 in 2014, 40% more than the average price in Switzerland, 53% more than in the United Kingdom, and 77% more than in Australia Heart disease is the leading cause of death for both women and men in the U.S. Cardiac surgeons, or heart surgeons, provide intervention to treat the disease. After years of intense study and specialized training, a heart surgeon typically earns between $300,000 and $450,000 a year

Transcatheter aortic valve replacement (TAVR) - Mayo Clini

If you are eligible, one of our health professionals will call you in 2-3 business days to discuss your situation and help to enrol you in the relevant program. There is no cost to participate, however some referred services may incur an out of pocket cost. Back to homepage Average Heart Stent Price. To understand the heart stent price, you should know the average angioplasty stent cost. According to Medigo.com, that is about $28,000 to $30,000. However, this can go as low as $15,000 depending on your location in the US. These figures are backed by the fair price posted by the Healthcare Bluebook Fast Track to Private Heart Surgery/Cardiology Treatment Private1 2019-07-02T09:09:25+00:00. Fast Track to Private Heart Surgery/Cardiology Treatment: Get advice or a quote. Get personalised advice from 3 of the leading private hospitals/clinics near you for free and get on the fast track to treatment Aortic valve replacement is a procedure whereby the failing aortic valve of a patient's heart is replaced with an artificial heart valve.The aortic valve may need to be replaced because: The valve is leaky (aortic insufficiency, also known as aortic regurgitation)The valve is narrowed and doesn't open fully (aortic stenosis)Current methods for aortic valve replacement include open-heart.

Compare The Cost Of Cardiac Pacemaker Insertion

Now we can start to answer the question how long does heart bypass surgery last?. Studies have shown that the LIMA graft is around 95-99% likely to be open and working at 1 month after operation, 90-95% likely to be open at 1 year - 5 years, and around 80-90% (even greater in some studies) likely to be open at >10 years We provide aortic stenosis treatment (TAVR), heart monitoring, heart valve treatment, vascular surgery and more. Heart rehabilitation and support: Beyond life-saving screenings and treatments, we offer support and rehabilitation for your lifelong heart health. Learn about exercise, prevention, medication management and more Valve replacement using traditional surgery - Defective heart valves can be replaced with a mechanical heart valve made of plastic or Dacron, or a biological valve made of tissue taken from a pig, cow or deceased human donor. After surgery, patients with mechanical valves must take anticoagulant medications to prevent blood clots Beating heart surgery. An innovation which has gone hand in hand with less invasive techniques is beating heart, or 'off pump' coronary surgery, which was developed in the 1990s and introduced at Harefield Hospital in September 1996. The heart remains beating, removing the need to stop the heart during the procedure An open mitral valve replacement is a surgery to replace a poorly working mitral valve with an artificial valve. The mitral valve is 1 of the heart's 4 valves. It helps blood flow through the heart and out to the body. The mitral valve lies between the left atrium and the left ventricle. Your doctor will replace your poorly working mitral.

This is how much it costs the NHS to perform an operation

The total cost of hip replacement surgery can be staggering if you don't have help from insurance. How much does a hip replacement cost with insurance? A total hip replacement costs anywhere from $32,000 to $45,000, based on general coverage guidance from healthcare.gov. The total cost usually includes everything from the surgeon's initial. Hospitals in Alabama have reported a price range of $30,000 to $120,000 for permanent pacemaker implants. The average cost of pacemaker implants with no complications across all US states are the following: Alabama $54,564. Alaska $55,814. Arizona $61,790. Arkansas $47,954 If the heart rate is too slow, the blood is pumped too slowly. If the heart rate is too fast or too irregular, the heart chambers are unable to fill up with enough blood to pump out with each beat. When the body does not receive enough blood, symptoms such as fatigue, dizziness, fainting, and/or chest pain may occur The best solution is to replace that valve. Traditionally, open-heart surgery was the best option, but a newer minimally invasive procedure called transcatheter aortic valve replacement (TAVR) is now approved by the Food and Drug Administration (FDA) for anyone with severe, symptomatic aortic stenosis. Although initially TAVR was approved only for patients at intermediate and high risk of. When you have aortic or pulmonic heart valve disease, valve replacement surgery is usually performed. In some cases, the aortic valve can be repaired. During valve replacement surgery, the faulty valve is removed and a new valve is sewn to the annulus of your original valve. The new valve can be a: Mechanical valve

How much does private cardiac surgery cost in the UK

Replacement valves made from cow tissue do not require warfarin, but Team Heart rarely uses them, because they wear out quickly in young people. Mechanical valves can last for decades Wondering how much back surgery costs for a herniated disc? It could range anywhere from $15,000 to $45,000.And anterior cervical surgery (the most common type of neck surgery) ranges from $20,000 to $70,000. (If you're interested in knowing the average cost of minimally invasive back surgery, it would be the same as for a conventional open surgery because insurance companies don't.

CABG is sometimes referred to as heart bypass or coronary artery bypass surgery. Heart valve repair or replacement. Surgeons either repair the valve or replace it with an artificial valve or with a biological valve made from pig, cow, or human heart tissue. One repair option is to insert a catheter through a large blood vessel, guide it to the. Thousands of heart surgeries are performed every day in the United States. In fact, in a recent year, surgeons performed 500,000 coronary bypass procedures. And even though there is a shortage of donor organs, more than 3,200 people have heart transplants each year The Cost of Pacemakers. The pacemaker price can be covered by Medicare or any other private care insurance. To those who are not covered by insurance, the average cost for it is in between $19,000 - $96,000 dollars depending on the type they are going to get. Location could also play a big factor in pricing and the length of the patient's. Aarhus University. (2017, June 7). Many good years after heart bypass surgery, but something happens after ten years: The probability of continuing your life following bypass surgery is close to. When it comes to surgical procedures, both Medicare and Medicaid provide coverage for many medically necessary surgical services received under inpatient and outpatient treatment. However, coverage terms can vary depending on the type of surgery being performed, where it is performed, and your specific circumstances. Understanding Different Types of Surgeries The Medicare and Medicaid program HOW THE HEART WORKS • The heart consists of 4 chambers and 4 valves • 4 Chambers: Right Atrium (RA), Right Ventricle (RV), Left Atrium (LA), Left Ventricle (LV) • 4 Valves: Tricuspid, Pulmonary, Mitral, Aortic • The arrows above show the direction of blood flow through the heart (starting at right atrium