Our heart valves are rightly called the doors of life. There are four of them, each at the entrance and exit of the upper and lower chambers of the heart. Their main function is to control the unidirectional flow of blood through the heart. It is the opening and closing of these valves that cause the normal heart to sound ‘lub dup’.
Like all the other organs of the body, the heart valves too are susceptible to diseases, both congenital (present from birth) and acquired. Earlier valve diseases had hardly any treatment and patients were compelled to lead a very poor quality of life and succumb to death early. But now, we have moved miles ahead, and even those with very complex valve disorders can enjoy a near-normal life.
(having three cusps)
Controls the flow of blood from right atrium to the right ventricle
(having two cusps)
Controls the flow of blood in between the right ventricle and the pulmonary artery
Controls the flow of blood between the left atrium and the left ventricle
Controls the flow of blood from the left ventricle to the aorta
In our country, rheumatic fever is one of the principal causative factors for valve disorders. Initially, it manifests as throat infection, pain in the joints that keeps on shifting, and fever. If improperly treated, rheumatic fever affects the delicate heart valves, causing them to be narrowed or to leak. Since it is most commonly seen among people from weaker socio-economic groups, the awareness level about early treatment of rheumatic fever is low, and often, young adults in their teens come down with valve disorders. Rheumatic fever can be effectively treated by long-term use of penicillin injection. But if valves are already affected, then appropriate treatment is necessary.
Sometimes, children may be born with improperly formed valves that are very tight or leaky. The valves may even be completely absent, sometimes.
Other acquired defects
Sometimes, abnormal deposits of calcium occur on the valve cusps, leading to their deformity. Presence of blood clots, infective pathogen-like a mass of fungus, bacteria etc, or even external mechanical injury may cause damage to heart valves. Some medications like prolonged use of antimigraine drugs, radiation treatment to chest area etc. can also precipitate valve damage.
Valve disorders are mainly two types: valve narrowing (stenosis) and valve leakage (regurgitation). Irrespective of which valve is affected, most valve defects produce similar symptoms that are directly proportional to the severity of the defect, the person’s activity level and general health. Valve disorders may manifest as:
Shortness of breath that progressively increases with exertion in the initial stages, and later, even at rest
Swelling of the legs, especially the ankles
Heart palpitations or rapid heart beat
Repeated chest infections
Severe cough, sometimes coughing up blood
Basing on the patient’s history, the doctor can suspect a valve disorder. On clinical examination, he/she may hear abnormal heart sounds called ‘murmurs’. This prompts the doctor to refer the patient to a cardiologist for detailed examination. An Echocardiogram with Colour Doppler reveals the nature and exact extent of the disease with the amount of blood flowing across the valves. A chest X ray and ECG is also done. Rarely, an angiogram is required for associated problems.
Once diagnosed, the cardiologist discusses the treatment options. Most cases of valve narrowing can be treated without surgery through Balloon Valvoplasty, where the narrowed valve is widened by wiring a balloon through a large blood vessel. Since it is non surgical, it leaves no scar and patients are discharged within two to three days, and can resume normal life almost immediately. Some precautionary medications are advised to prevent further infliction to the valves.
Valve replacement surgery
When there is severe leakage in the valves or the valve is severely deformed due to calcification or other reasons, the viable option of treatment is a valve replacement. Artificial heart valves are of two types: mechanical or tissue.
Mechanical heart valves, as the name implies, are made of metals and are of various types: ball and cage, tilting disc and bileaflet. Depending on the designer, they are called Starr Edwards, Medtronic-Hall, St. Jude, ATS and so on. They last for a very long time (20-30 years) and allow the patients to lead a normal, active life. The only significant disadvantage of this type of valve is the tendency to form blood clots or thrombus around the metallic surfaces. To prevent this serious consequence, patients have to be on lifelong anticoagulation. Usually, the medication Warfarin (Coumarine group) is given, which reduces the clotting tendency and keeps the valves working smoothly. Patients have to undergo a monthly blood test to check their INR (International Normalised Ratio), which is an index of the clotting ability. The medication is thus adjusted to the minimum safe dosage so as to reduce the risk of serious internal or external haemorrhage.
Biological heart valves are principally harvested from animals. The pig’s (porcine) heart valve is frequently used since it is anatomically very similar to the human heart valve. This type of surgery is called xenotransplantation. The other type of biological valve is made out of the pericardial sac of cows or horses. These valves also work very well. But these valves do not grow with the patient and may need a replacement in future.
Ross procedure is a surgery where the severely diseased aortic valve is replaced by the patient’s own pulmonic valve, and the pulmonic valve is replaced by a cadaveric valve. The pulmonic valve, working under low pressure, is slow to develop any dysfunction. These types of valves grow with the patient and thus give freedom from the prospect of re-operation. Anticoagulation is also not required for this type of replacement since no metallic surface is present. This is the procedure of choice, particularly for children, with severe aortic valve disease. Some hospitals today offer the facility of valve banks, where cadaveric valves are harvested and preserved.
Life after valve replacement
The principal purpose of any therapy is to give back a normal active and good quality of life to the patients. Thus after a successful valve replacement surgery, patients are to be able to pursue their education, job, active social life and would be in no way different from their heart-healthy counterparts. But they need to be under regular medical checkup, as advised by their cardiologists. Those on anticoagulation therapy should have their blood tests done as scheduled and take the medicines without fail. Rough contact sports like rugby should be avoided to minimize the risk of injury and bleeding. Periodic tests like echocardiogram may be needed to assess the functioning of the valves.
There is no restriction in marriage and having a family. But women who look forward to be mothers, should discuss with their cardiologist before planning for conception and keep in constant touch with him throughout the pregnancy and childbirth, so that medications can be properly adjusted for the safety of both the mother and the child.
Development of any symptoms like shortness of breath, unexplained exhaustion, swelling of ankles, fever and severe cough should never be ignored and promptly reported to the cardiologist to rule out any valve dysfunction.
As mentioned earlier, valve surgery has come a long way since its introduction in the fifties. It is important to perform the surgery at the opportune moment to prevent irreversible damage and to allow the patients to enjoy the maximum benefit of this life-saving procedure.