The article provides information on what a circadian index is. Normal values of the indicator, which states lead to its change. Whether always it is a question of a pathology, or it can be physiological feature. Symptoms of violations, methods for their correction.
Contents of the article:
- Reasons for changes in the circadian index
- Symptoms of changes
- Diseases and evaluation of the circadian index
- Treatment of the pathology
- Forecast
The ratio of the average rate of heart rate reduction in the daytime to the average rate of contractions at night in medical practice is called the circadian index. Numerical heart rate readings are obtained during ECG recording during the day, using Holter monitoring. The study is assigned by a therapist or cardiologist to assess the performance of the heart muscle against the backdrop of daily stress and during night rest.
Calculation formula for the circadian index The circadian index is normally in the range 1.24-1.44.At a serious cardiological pathology at a stage of decompensation there is a decrease in the index less than 1,2 - the rigidity of the circadian rhythm. An index change of more than 1.5 may be the physiological norm in trained people or be noted in extrasystoles( additional cardiac contractions at a normal rhythm).
A persistent change in the indicator in the lower direction characterizes a serious problem in the functioning of the heart muscle and a high risk of death. When the indicator changes to a larger side - the prognosis is favorable, the treatment is usually effective and successful.
A decrease in the circadian index is a sign of chronic heart failure. Complete recovery from the disease is impossible, but properly selected therapy will significantly improve the prognosis for life. Patients with such pathology are guided by a cardiologist, the earlier they are prescribed treatment, the higher the chance to maintain a habitual way of life.
Graph of circadian changes in the HF component in different age groups. HF component - high-frequency heart rate used for ECG recording Causes of changes in the circadian index
Heart monitoring reflects the response of the muscle to any changes during the day. A normal reaction to physical activity is an increase in heart rate, and during the rest period the heart rhythm comes back to normal. If there is a violation of the nervous connection of the heart with the nervous system of the organism, there is no increase in rhythm, any load leads to a deficiency of blood supply to the tissues - the cardiac muscle also suffers, aggravating the pathology.
In healthy people and patients with compensated cardiac abnormalities, the circadian index averages 1.32 ± 0.06-0.08.The main reasons for the output of the indicator beyond the limits of the norm are given in the table:
| Index value | Reasons for |
|---|---|
| & gt;1,5 | Normal for professional athletes Parasympathetic nervous system lesion( responsible for almost all natural functions: secretion of secretory substances in the gastrointestinal tract, loss of heart rhythm at rest, constriction of pupils, etc. - maximum activity during rest period) patients with rhythm disturbances of the type of extrasystole( additional contractions of the heart against the background of normal rhythm) or ventricular and atrial tachycardia( acceleration of the rhythm of contractions of the heart) without organic damage to the heartmuscle muscle Primary pulmonary artery pressure increase Congenital vagotonia( parasympathetic nervous system predominant activity) |
| & lt;1,2 | Diseases affecting the nerve fibers of the heart muscle( chronic and acute ischemic heart disease, cardiomyopathies( muscular tissue damage) of any nature) Side effect of a number of drugs against heart rhythm disorders |
Symptoms of changes
Each disease has its own manifestations, andthe definition of the circadian index requires the advice of a medical professional. Symptoms that alarm and require recording to a therapist or cardiologist for daily monitoring:
- dizziness, impaired consciousness without trauma to the head area;
- frequent or rare heartbeat of a permanent or temporary nature;
- irregular pulse( different time intervals between strokes of the heart);
- pains in the chest on the left, especially those that arise against the background of the load and give up in the hand;
- any of the listed symptoms, if they appeared against the background of the beginning of taking medications to correct the heart rhythm;
- shortness of breath, cough, chest pain, worse with exercise.
These symptoms are not always accompanied by a change in the cyclicity of the heart, but any of them, much less their combination - the reason to immediately seek medical attention.
Diseases and evaluation of the circadian index
A number of diseases are characterized by a negative effect on the nerve fibers of the heart muscle. With the progression of pathology, the circadian index also changes, which requires regular Holter monitoring to evaluate the index in dynamics and, based on it, correction of treatment and prognosis for the disease.
Holter monitor allows monitoring pulse and ECG round the clock Pathologies, in the standards of observation and examination of which the definition of the circadian index is included:
- Myocardial infarction - evaluation of an indicator, both in an acute period and during a dynamic observation.
- Acute disruption of cerebral blood flow( stroke) - in an acute period to assess the ability of the heart muscle to cope with the load.
- Arrhythmias( irregular heartbeat rhythm) of any kind and severity - evaluation of circadian index is necessary before and during treatment.
- Cardiomyopathies( degeneration, pathological changes in heart tissue) of all types - the value of the indicator is assessed regularly to determine the extent of the lesion, the risk of sudden death.
- Chronic heart failure - the frequency of evaluation is determined by the cardiologist depending on the clinical manifestations.
- Primary pulmonary hypertension( increased pressure in the vessels of lung tissue) is an evaluation in dynamics with the aim of revealing the connection of heart failure.
- Diabetes mellitus of any type - the index is evaluated annually, with severe current with high glycemic numbers - more often.
- Cardiac muscle defects, including after surgical correction - cardiac monitoring is performed according to indications.
If the circadian index is reduced, this is the reason for the immediate initiation of treatment, since it is a question of transition of the compensated stage of heart failure to decompensated. Lack of therapy can lead to sudden death. The increase in the indicator is not so fatal, it is adjusted well enough.
Treatment of
Given that any change in the circadian index is a manifestation of a disease or functional condition, correction is indicated for treatment of the underlying disease.
General principles of therapy are composed of:
- timely detection and treatment of chronic heart failure( regardless of the type of primary pathology);
- individual dose selection, type of medicines for therapy of cardiac rhythm disturbances;
- modern types of treatment of acute circulatory disorders in the tissues of the heart muscle and brain;
- correction of increased pressure in the pulmonary arteries;
- control of blood sugar, its stabilization.
Forecast
All diseases that cause a decrease or increase in the rate of cyclicity of the heart - a chronic course, there is no complete cure, but in time and correctly selected line of therapy significantly improves the quality of life, reduces the risk of death. Treatment of pathological processes should be permanent, the abolition of drugs leads to a worsening of the condition.
A poor prognosis is characterized by a persistent decline in the indicator against the background of the treatment. The condition, when the circadian index is below 1.1, is called "vegetative de-innervation" - this is a sign of irreversible disorders leading to sudden cardiac arrest.
