Cardiac rhythm disorders
Rhythm disorder is not the same as palpitation contrary to popular belief. However, palpitation may be an indicator of rhythm disorder. When it comes to rhythm disorder, one should think of a heart beating slower or faster than normally, or at an irregular rate. Heart muscle cannot pump enough blood into the body when heart beats outside its normal rate. Therefore, complaints such as weakness, dizziness, chest pain may occur. If rhythm disorder is severe, heart failure or even shock may develop. In palpitation (tachycardia) which is manifested as the heart rate scaling up to values of 140 and above from 100 per minute which is the upper limit, a specialist physician should be consulted as soon as possible. ECHO test, thyroid functions and presence of anemia should be looked into for identifying the reasons for palpitation which is seen as heart rate value above 140. This test can help determine whether palpitation is physiological (sinus tachycardia) due to excitement, stress, fast running or excessive caffeine consumption or cardiac rhythm disorder (arrhythmic tachycardia).
Rapid heart beat due to changes in emotion is physiological and normal. Other than these, although there is no problem, heart can beat rapidly in case of anemia, high fever, overactive thyroid or panic disorders. These conditions do not result from a cardiac rhythm disorder. Since throbbing is the most frequent sign of cardiac rhythm disorders in children and young people, nevertheless, a child with the complaint of palpitation should be examined by a pediatric cardiologist, preferably one who was trained in pediatric electrophysiology.
Causes of arrhythmia
Rhythm disorders may occur alone or be observed due to other reasons such as previous heart surgeries. Some types of arrhythmia are genetic. If one of the family members has genetic arrhythmia, it is highly likely that other members will develop arrhythmia too. Arrhythmia can occur in structurally normal hearts as well as being one of the findings of cardiac abnormality. Heart rhythm is disturbed due to either problems in the management center of heart or interruptions in the conduction paths, excesses or a group of cells at any point of heart not listening to the center and having a mind of its own. In this case, heart rate starts to become irregular. Heart may slow down too much (bradycardia) or beat too fast (tachycardia). Some of the diseases such as myocarditis, cardiomyopathy that affect heart muscle can damage the cells in the abovementioned management center or cells damaged in another area may cause irregular rhythms by losing their normal functions. Tachycardia in case of hyperthyroid and anemia and bradycardia and blocks in hypothyroid are frequent rhythm disorders. Some of the malfunctions in the conduction paths may be congenital. Some drugs used in the treatment of asthma and cold, tea, coffee and stress have a triggering effect on rhythm disorders in arrhythmia-inclined individuals. Arrhythmia accompanied by severe hearth failure and cardiovascular diseases may even cause death. Lifestyle is also effective on heart rhythm. Factors such as nutritional habits, sleep patterns, active or sedentary lifestyle may trigger a rhythm disorder. Excessive consumption of energy drinks may cause severe rhythm disorders. Moreover, electrolyte imbalance (disturbed levels of elements in blood such as sodium, potassium and magnesium) can cause a rhythm disorder. To sum up, all risks that can cause heart diseases are also risks for the rhythm disorders.
Does it cause other diseases?
Heart of a healthy adult beats 60-100 times per minute, which occurs in a certain order. How the individual feels a disturbance in his/her heart beat is considered “arrhythmia”. For instance, acceleration of heart beat draws attention when running, climbing stairs, during excitement or under emotional stress. But if heart beats are felt with no reason, this may mean a problem with heart. Arrhythmia may also bring along the risk of stroke. Atrial fibrillation (AF), or abnormal hearth rhythm or arrhythmia, can increase the risk of stroke 4-5 times even without another underlying heart disease such as heart valve diseases. About one-third of all strokes is thought to develop in association with arrhythmia. Arrhythmia-related stroke has a more severe and fatal course. Frequency of stroke increases with age in arrhythmia. Several factors other than age increase the risk of having a stroke. If conditions such as diabetes, hypertension, heart failure, previous stroke, transient ischemic attack or other vascular disease, and female gender accompany arrhythmia, the risk will increase further.
What are the symptoms?
The most frequent symptom of arrhythmia is palpitation. The most common symptoms include the sense of “throbbing” in heart, feeling irregular heartbeats, dizziness, blackout, sense of tightness in chest, pressure or pain, syncope (temporary blackout-fainting). When one or a few of these symptoms are present, one needs to consult a specialist. Electrocardiography can identify the type of arrhythmia to help choose the most suitable treatment. Nevertheless, if electrocardiography could not be performed during the palpitation, rhythm “Holter” can be used to show the heart rhythm in another period of time. Aside from these methods in the diagnosis of arrhythmia, “transtelephonic Holter” and implantable recording devices can also be utilized. Slowness in heart may be the indicator of block in the conduction system, and while this is treated with permanent pacemakers, “radiofrequency ablation” is performed in the treatment of arrhythmia associated with acceleration of heart with no reason.
Rhythm disorders in children
Rhythm disorders in child may occur due to changes in the biochemical balance of blood, infections affecting the heart and substance abuse. Complaints such as rapid heart rate (palpitation), getting tired quickly, difficulty in breathing, chest pain, sweating, and effort-emergent fainting stand out in children with rhythm disorders. Weakness, getting tired quickly while sucking, rapid and frequent breathing, change in skin colour are observed in babies. Furthermore, heart failure and even shock findings may emerge if arrhythmia is not noticed for a long time. In intermittent rapid arrhythmia, no complaint is observed in babies during normal periods between attacks while mother can observe these findings only during the attack or feel that child’s heart is beating extremely fast when she puts her hand on the heart. Slow rhythm disorders manifest themselves mostly as getting exhausted very quickly and falling behind compared to peers in the games that require physical effort in older children. Rapid rhythm disorders are typically expressed as palpitations. As the most frequent type, SVTs start suddenly and cause palpitation attacks that stops suddenly in general. It can sometime be expressed as fatigue, rapid breathing, dizziness, fluttering in chest or neck vessels or chest pain as well. Sometimes these can be diagnosed only by current pulse check or ECG during the attack. Fainting, or syncope, should be examined by a pediatric cardiologist and especially a pediatric electrophysiologist before a neurologist. Because, if there is no evident finding of attack, fainting is mostly associated with cardiovascular system. The fact that such patients first see a neurologist leads to unnecessary tests such as CT, EEG and the delay in diagnosis and treatment. On the other hand, rhythm disorders may not manifest themselves for a long time at all and can only be noticed by the physician during routine examination or with ECG taken for another reason. The first finding in some dangerous types of arrhythmia can be fainting, or even sudden death.
Whereas some of the rhythm disorders are temporary in children, most of them are permanent. Especially the rhythm disorders causing tachycardia are generally caused by redundant electrical conduction paths which are congenital in heart. Either medication is used depending on the patient’s age, type and severity of rhythm disorder or a procedure called ablation is performed. Some of rhythm disorders, especially those occurring during infancy tend to recover over time. Medication is not the definitive solution but only suppresses the arrhythmia.
Treatment of arrhythmia
The most basic approach in arrhythmia treatment is the elimination of abnormal heart tissue which causes the condition. If surgery is required for the treatment of other heart issues (valve disease or coronary artery disease) in a patient with arrhythmia, the arrhythmia can be easily treated without an additional surgical risk. Scientific guidelines importantly recommend that the concomitant arrhythmia, if any, should be treated during the isolated aortic valve disease surgery and isolated heart bypass surgery or the surgery combining these two surgeries. Today, new methods using the new technologies designed to create conduction blockage lines through radiofrequency, microwave, laser, ultrasound or cryoablation (freezing) are commonly used in the surgical treatment of arrhythmia.With these techniques, lesions and then a scar tissue are inflicted to prevent the conduction of abnormal electrical stimuli through the heart, and so, normal stimulus conduction through the right path is reinforced. Among these, radiofrequency and cryoablation that can be performed during surgery are the most popular.
Cryoablation (Freezing) Method:
Cryoablation is a method that has recently started to be used around the world and has fewer complications than the older methods. In this method, the problematic area of the heart is frozen down to minus 150-170 degrees. Complaints of palpitation are prevented with this method. Low risk of perforation and thromboembolism and achieving full-layer lesion are the biggest advantages of this method.
Radiofrequency Ablation Method:
The principle of this method is to inflict full-layer lesions in certain areas of “atrial endocardium” using the heat of the radiofrequency energy. In this way, both the isolation of focuses triggering the arrhythmia and the large reentry circuits advancing in waves are prevented from advancing by catching newly created lesions and natural anatomical obstacles. Catheter is moved on toward heart through groin. The tip of the catheter is connected to the recording device to keep intracardiac ECG records and the focus causing palpitation is found. Next, radiofrequency is released via catheter to inflict damage in this area, so the responsible focus was eliminated. A success rate of over 90 percent can be achieved in most of the rhythm disorders with the ablation method. With this method, palpitation is eliminated and so patients do not take drugs during their whole lifetime. “Radiofrequency ablation” is preferred in the cases in which medication is not successful.
Taking the arrhythmia under control and treating it early will prevent the disease from reaching fatal levels. Hence, every child should be subjected to a heart examination before starting the school. Examination to be performed in the preschool and primary school period in particular can prevent future sudden death due to arrhythmia via ECG and ECHO. Heart failure that may even occur at the age of 20s can be avoided.
Some of the rhythm disorders can also be treated with pacemakers. The patient with pacemaker needs to be kept under constant control.