Tuesday 23 August 2011

VALVULAR HEART DISEASE......



What are valves and what is the anatomy of the human heart?
The heart is a marvel of nature. It is a hollow, muscular organ about the size of your fist. It lies in the centre of the chest, slightly to the left. It beats almost one lakh times a day, day after day, year after year. It is made of a unique muscle called myocardium, which is the main propelling force of the heart. It pumps blood in the body with each beat of the heart. This happens 60-90 times a minute. It’s obvious that for the proper functioning of the heart, the myocardial muscle has to be healthy. Myocardium gets its nutrition and oxygen through blood, which is supplied by coronary arteries.

The heart is divided into two parts, the right heart and the left heart.  Right heart has two chambers, right atrium and right ventricle.   Similarly the left side heart has two chambers – left atrium & left ventricle. So in all, there are four chambers in the heart. The right side of the heart receives impure blood from the body and pumps it into the lungs. Blood gets purified in the lungs and returns to the left side of the heart. From here it is pumped back to the entire body for supply of oxygen  & nutrition. Four valves, two on the left side of the heart (mitral and aortic) and two on the right side (pulmonary and tricuspid) act as one-way doors to direct the flow of blood.
What are the diseases of the valves of the heart?
The valves can be afflicted with a number of diseases like rheumatic fever, birth defects, infection, injury or degenerative disorders. The most common of these in India is rheumatic heart disease, which is caused by an infection of the throat by special bacteria called beta haemolyticus streptococcus. The sore throat produced by this bacterium is virtually like any other sore throat, but with a difference, that it is associated with fleeting and migratory pain and swelling in the major joints of the limbs, like knee and ankle. In fact the swelling and pain goes away over a period of time and the patient generally tends to forget these symptoms totally. After a gap of 5-7 years, this infection damages the valves of the heart by an auto-immune process thereby producing rheumatic heart disease.
What is the effect of rheumatic heart disease on the valves?
The valves can be affected in two ways - either they get scarred, thickened and fused, thereby producing narrowing of the valves  (stenosis), or they can start leaking, due to again scarring or rupture of the supporting system (regurgitation). When the heart valves do not open or close, as they should, the heart has to pump harder to get blood to the body. This can weaken the heart and damage the lungs, liver and other parts of the body.
What are the clinical symptoms of valvular damage?
The patient may present with shortness of breath, palpitation, chest pain, swelling of the body specially feet, weakness, lethargy and some times blackouts and dizziness/giddiness. In the initial stages the patient may be totally asymptomatic and may have just subtle reduction in effort tolerance.
What is the best test for evaluating the valves of the heart?
Echocardiography (2D or 3D) currently is the gold standard for diagnosis of valvular heart disease and in most cases is able to give definitive answer to all the queries and doubts about the disease process. Some times cardiac catheterization may be required, if echocardiography is not confirmatory in its findings/diagnosis.
What is the treatment for rheumatic fever?
Rheumatic fever is essentially treated with antibiotics in form of injectable Penicillin or oral erythromycin, if the patient is sensitive to penicillin. For swelling and pain in the joints, any one of the non steroidal anti inflammatory agents can be used, but Aspirin is the most specific. Most patients need no further treatment but in a small percentage of patients, steroids may be needed. Penicillin treatment should be continued for as long as the doctor prescribes it for and should never be stopped in between, as this disease has chance of recurrence and some times penicillin is prescribed as 3 weekly injection till the age of 35 or even beyond as per the clinical demands.
What is the treatment for rheumatic heart disease?
Rheumatic heart disease essentially consists of either narrowing of the valve or leak in the valve. If the valve is narrowed then it can be opened by balloon valvotomy, which is a procedure requiring no cuts and no anaesthesia and is done just like an angiography in the cardiac cath lab, and involves a stay of around 3 days in the hospital. However, if the valve is damaged beyond a particular point then it cannot be opened either by balloon valvotomy or even by an operation and the valve has to be changed by an open-heart surgery. If the valve is leaking, then every attempt is made to repair the valve surgically. However, if the valve is heavily scarred and the supporting structure is damaged beyond repair, then the valve has to be replaced.
What are the types of artificial valves?
There are essentially two types of valves:
  • Tissue valves, which are made from the tissues derived from the pigs and cows. These valves have the advantage that they do not need life long blood thinning tablets, but they have the disadvantage that their life is limited and usually a tissue valve lasts from 10-15 years.
  • Mechanical Valve. It is made of a special kind of metal and has the advantage of being long lasting, but the biggest disadvantage with mechanical valve is that blood clots tend to form on them and therefore one has to take blood thinning tablets for life time.
What precautions one needs to take after valve surgery?
After valve surgery, one needs to take blood thinning tablets, specially if it is a mechanical valve, for life long and the levels of blood thinning medicine has to be maintained by doing a test called INR/PT. This test must be done once in a month and the INR level should be maintained around 2.5 – 3.5 times the normal, or as prescribed by the treating physician. In general, low salt and restricted fluid intake are good for healthy life. If there is any problem maintaining the INR level, then one may have to avoid taking green leafy vegetables and tomatos etc. When ever one has to undergo any form of surgical or gynaecological or dental treatment, then one must inform the doctor that there is an artificial valve in his heart, so that the necessary precautions for preventing infection on the valve can be taken by the treating physician. Also if one is taking anticoagulants or blood thinning tablets, then one must carry a warning card in the pocket or in the purse all the time, so that in case of an emergency, treating doctor gets warned about the blood being thin. One must never walk bare feet and be little careful while trimming nails and while using sharp objects, because one is likely to bleed excessively if any injury takes place. In case there are any symptoms, one must report to the doctor immediately and not delay presenting to the hospital.
Can young ladies conceive after valve surgery?
Yes, ladies can conceive absolutely normally after valve surgery and they can have a productive and a fruitful life, both as a mother and as a wife. However, whenever one wants to conceive, one must consult the treating doctor and avoid taking blood thinning tablets during the conception period of first three months and substitute it with one injection a day of low molecular weight heparin, but this must be done under medical supervision.
Myths

  • Once the rheumatic fever is treated, one need not take penicillin prophylaxis. This is absolutely wrong. If a rheumatic fever is confirmed then one must take penicillin injection every three weeks till the minimum age of 21 years or for at least 5 years beyond the last episode of rheumatic fever. If one has a diagnosed valvular heart problem, then one must take penicillin injection till the age of 35 years at least, and according to some doctors, for life long. If one ignores this precaution, then the disease can recur and progress and involve the other valves of the heart also.
  • Once one valve is replaced, the other valves do not need caring. This is absolutely wrong, because the other 3 valves, specially aortic and tricuspid valves, are also prone to involvement by the rheumatic process and even after a valve replacement operation, penicillin injection should be taken to protect the other valves.
  • Blood thinning tablets can be stopped after 3-6 months. Stopping blood thinning tablets in mechanical valves is disastrous and can lead to life threatening complication of valve clotting off and some times even producing sudden cardiac death. Therefore one must be very clear that blood thinning tablets have to be taken for life in mechanical valves.


What is lipid profile?



The lipid profile is a blood test done to assess the status of fat metabolism in the body and is important in heart disease. This includes measuring lipids (fats) and its derivatives known as lipoproteins. Lipoproteins are compounds containing fat and proteins and include free cholesterol, cholesterol esters, triglycerides, phospholipids and apoproteins. 
Which biochemical markers are used?
The blood is analysed by the laboratory to determine the levels of:


  • Total cholesterol 




  • Triglycerides 




  • HDL (high density lipoprotein) cholesterol 




  • LDL (low density lipoprotein) cholesterol




  • Serum VLDL (very low density lipoprotein) cholesterol

    Total cholesterol comprises all the cholesterol found in various lipoproteins such as high-density lipoproteins (HDL), low-density lipoproteins (LDL), and very low-density lipoproteins (VLDL). A total cholesterol test is a rough measure of all the cholesterol and triglycerides in the blood.

    Triglycerides are neutral fats found in the tissue and blood. Triglycerides containing lipoproteins may also contribute to the disorders related to coronary heart disease. Persons with high triglycerides often have other conditions, such as diabetes and obesity, that also increase the chances of developing heart disease.

    The main function of HDL is to help soak up excess cholesterol from the walls of blood vessels and carry it to the liver, where it breaks down and is removed from the body in the bile. It is thus called “good” cholesterol as persons with high levels of HDL may have a lower incidence of heart disease.

    LDL contains the greatest percentage of cholesterol and is responsible for cholesterol deposits on the walls of the artery resulting in coronary artery disease. LDL is thus known as the “bad” cholesterol. VLDL stands for very low density lipoprotein. VLDL contains the highest amount of triglyceride. VLDL is considered a type of bad cholesterol, because it helps cholesterol build up on the walls of arteries. Normal VLDL cholesterol level is between 5 and 40 mg/dL.

    The cholesterol/HDL ratio is derived by dividing the total cholesterol by the HDL. This ratio helps in assessing the risk of heart disease in individuals. 



  • What are the desirable lipid profile values?
    Lipid profile values can be evaluated from the table below:

    Adult valuesDesirableBorderlineHigh risk
    Cholesterol<200 mg/dl200-239 mg/dl240 mg/dl
    Triglycerides<150 mg/dl150-199 mg/dl200-499 mg/dl
    HDL-cholesterol60 mg/dl35-45 mg/dl<35 mg/dl
    LDL-cholesterol60-130 mg/dl130-159 mg/dl160-189 mg/dl
    Cholesterol/HDL4.05.06.0
    What preparations are required?
    The patient needs to be fasting for 12–14 hours before drawing the sample. He should also be on his normal diet pattern. Intake of alcohol on the previous night should be avoided.
    What are the factors that affect lipid profile?
    Factors that affect an individual’s lipid profile include:
    • Age
    • Sex
    • Body weight
    • Alcohol and tobacco use
    • Exercise
    • Genetic factors
    • Medications
    • Chronic disorders such as hypothyroidism, obstructive liver disease, diabetes, and kidney disease


    How young is your heart?




    A healthy heart is vital for healthy living, regardless of one's age or gender. One can prevent major cardiovascular risks, like heart attacks and strokes by choosing a healthy diet, being physically active and not smoking. This will help the heart to age more slowly.

    Physical activity and heart health

    Physical inactivity is a significant contributor to the ageing of heart, as it can lead to excess weight gain and obesity, diabetes and hypertension. Heart is a muscle that needs regular exercise to keep pumping blood efficiently with every heart beat. Regular activity and its effect on the associated risk factors will help:
    • Slow down the narrowing of arteries to the heart and brain
    • Encourage the body to use up excess stored fat, so it is crucial in helping weight loss and fighting obesity
    • Improve cholesterol levels by increasing the level of good cholesterol (HDL) in the blood
    • Maintain normal blood glucose levels in order to manage diabetes
    • Reduce high blood pressure
    • Smokers to quit - smokers who exercise are twice as successful in their attempts to stop smoking
    Being active also improves the overall health, gives more energy, reduces stress, builds stronger bones and muscles, and improves balance, strength and mobility.

    What type of activity is best?

    For overall good health one should include aerobic (endurance type) and strengthening activities and stretching exercises:
    • Aerobic activity is the best exercise for the heart. This includes brisk walking, jogging, swimming, cycling, gardening, etc; any activity that uses the heart, lungs and muscles over a period of time. As well as strengthening your heart, exercise uses up calories, helping with weight control.
    • Strengthening activities work on the stomach and lower back muscles. Stronger, larger muscles use up more calories, so climbing stairs, digging in the garden and walking uphill will help to maintain a healthy weight.
    • Stretching exercises help promote flexibility by including activities such as T'ai Chi and yoga.
    Choose to move!

    Start exercising slowly and increase the time, intensity (high breathing rate but still able to speak) and frequency of activity as the heart gets stronger. For adults, at least 30 minutes of exercise a day and for children 60 minutes a day will help reduce risk factors. Although physical activity is perfectly safe for most people, sometimes it's important to ask for a doctor’s advise before exercising.

    A healthy diet

    To help maintain a young heart for life, calories consumed must be balanced with calories burned. It is therefore recommended to combine exercise with a balanced diet including plenty of fruits and vegetables, whole grain products, lean meat, fish and pulses, as well as low-fat and fat-free products, unsaturated soft margarines and oils such as sunflower, corn, rape-seed and olive oil.

    Say no to tobacco

    Smoking, or any use of tobacco, is another important risk factor of heart disease. Quitting using tobacco lowers blood cholesterol and low-density lipoprotein "LDL" cholesterol (bad cholesterol) levels, reduces blood clotting and the chance of a sudden blockage of an artery. Setting a good example by not using tobacco gives a clear, consistent message about the dangers of tobacco to children.

    Be successful

    A big part of maintaining a healthy lifestyle depends on knowing how be motivated along the way. Here are some steps that could help:
    1. Find the appropriate information needed. A local heart charity can provide information about risk factors and the actions to be taken to reduce these.
    2. Be aware of risk areas. These include family history, Body Mass Index (BMI), waist circumference, blood pressure, cholesterol levels, cigarette smoking and physical inactivity.
    3. Set achievable goals. Break down goals for healthy eating and physical activity into small achievable parts and develop an action plan to keep on track.
    4. Keep track of the progress. Keep track of activities and successes and reward yourself each time you achieve a goal.
    5. Take support from people around. The people around can be highly motivating by participating in a healthy lifestyle, or by reminding to keep up with new habits.
    6. Avoid perfectionism. If you miss an exercise, succumb to tobacco cravings, eat an unhealthy meal, just get back on track immediately with more determination to establish a heart-healthy lifestyle.


    How to keep the heart healthy in summers.....

     

  • Slow down- strenuous activities should be reduced, eliminated or rescheduled to the coolest time of the day. Individuals at risk should stay at the coolest available place, not necessarily indoors.

  • Dress for summer- lightweight light coloured clothing reflects sunlight and heat and helps the body maintain normal temperatures.

  • Put less fuel on your fires. Foods like proteins that increase metabolic heat production also increase water loss.

  • Do not drink alcoholic beverages.

  • Do not take salt tablets unless prescribed by a physician. People on salt restricted diet should consult their physicians before increasing the salt intake.

  • Spend more time in air-conditioned places- air-conditioning at home and other places reduces the danger from heat. If you cannot afford an air-conditioner then spending some time each day in an air-conditioned environment affords some protection.

  • Don’t get too much sun- sunburn makes the job of the heat dissipation that much more difficult.

  • Drink plenty of water or other non-alcoholic beverages. The body needs water to cool. Persons who have epilepsy or heart, kidney, or liver disease, are on fluid restrictive diets, or have a problem with fluid retention should consult a physician before increasing their consumption of fluids.



  • Who will and won't survive a heart attack ?



    It may be possible to predict who will survive or die as the result of a first heart attack.

    Researchers analysed data from 18,497 people in two of the largest American cardiovascular studies and pinpointed certain traits that could predict the risk that a heart attack would be fatal. Those traits included having high blood pressure, being black and having a very high body mass index (BMI) - a measurement based on height and weight.

    For some people, the first heart attack is more likely to be their last. For these people especially, it is important that ways are found to prevent that first heart attack from ever happening because their chances of living through it are not as good.

    It was found that high blood pressure and a high heart rate were stronger predictors of sudden cardiac death than coronary heart disease. Extreme high or low BMI was predictive of high risk of sudden cardiac death, but not of coronary heart disease. Certain markers that can be identified by doctors evaluating patients' electrocardiograms (ECGs) are associated with high risk of sudden cardiac death.

    If the findings are validated and confirmed in future research, it will be possible to identify patients who are at greater risk of dying if they suffer a heart attack and prescribe ways to reduce their risk.