Cardiac Arrhythmias

Many people have abnormal heart rhythms during their lifetime. Healthy people sometimes notice that a beat skips or the heart stumbles. Such extra blows (so-called extrasystoles) are to a certain extent harmless and harmless (especially for young people). But sometimes these stumbling blocks indicate serious heart disease. Here you will find everything about the symptoms, causes, and treatment of cardiac arrhythmias.

Definition

In the case of cardiac arrhythmias, the sequence of heartbeats is disturbed: the heart beats too fast, too slowly or too irregularly. In healthy adults, the heart beats about 60 to 80 times a minute when at rest and without exertion. With excitement, anger, fear, or stress, as well as physical strain, the heartbeat accelerates. On the other hand, it decreases during sleep. These changes are normal and important. In the case of cardiac arrhythmias, this adjustment of the heartbeat does not work properly.

Sinus nodes and AV nodes – clocks for the heart rhythm

The so-called sinus node in the heart indicates how fast and often the heart beats. However, this sinus node is not a palpable or tactile node. Rather, it is an accumulation of specialized heart muscle cells.

The sinus node is the first clock of the heartbeat. It is located in the upper area of ​​the right atrium and generates around 60 to 80 so-called excitations per minute. From there, these electrical impulses reach the AV node via the walls of the atria. This node lies at the transition between the atrium and the ventricle and steps in when the sinus node fails. It is like a downstream (secondary) pacemaker. However, the AV node produces only 40 to 50 excitations per minute. From the AV node, the electrical stimuli pass through specific conduction pathways into the muscles of the heart, which make the heartbeat.

Classification Of Cardiac Arrhythmias

Cardiac arrhythmias are classified according to their place of origin. They can arise in the atrium or the ventricle as well as in the stimulation and conduction system. There are also classifications according to speed and danger, as well as congenital and acquired cardiac arrhythmias. We limit ourselves to the classification of cardiac arrhythmias according to their place of origin.

Cardiac Arrhythmias

Atrial Arrhythmias

Arrhythmias that arise in the atrium of the heart are called supraventricular arrhythmias. As a rule, pathological changes in the sinus or AV node are the cause.

Typical atrial arrhythmias are:

    • Atrial fibrillation (most common significant cardiac arrhythmia. With atrial fibrillation, non-directional electrical excitations run across the atria at an immense speed.
    • Atrial flutter (abnormal heart rhythm in which the auricles beat regularly but very quickly per minute)
    • Conduction disorder from the sinus node to the atrial muscles (sinoatrial block).
    • Heartbeats outside the normal heart rhythm, originating in the atrium (supraventricular extrasystoles).

Cardiac Arrhythmias In The Ventricle

Arrhythmias that arise in the chambers of the heart are called ventricular arrhythmias. Typical cardiac arrhythmias in the ventricle are:

    • Heartbeats outside the normal heart rhythm from the ventricle (ventricular extrasystoles)
    • Rapid, sometimes life-threatening cardiac arrhythmias that originate in the ventricles (ventricular tachycardia)
    • Ventricular flutter (rapid sequence of relatively regular ventricular actions)
    • Ventricular fibrillation (life-threatening and pulseless cardiac arrhythmia with disordered ventricular excitation, whereby the heart muscle no longer beats properly. If left untreated, ventricular fibrillation leads directly to death due to the lack of pumping capacity).

Cardiac Arrhythmias Of The Excitation And Conduction System

    • Malfunction of the sinus node and conduction in the atria (e.g. sick sinus syndrome, sick sinus node syndrome)
    • Delayed or interrupted conduction of excitation at the AV node (AV blockages)
    • rapid and regular heartbeats that begin suddenly and end abruptly (AV node reentry tachycardia)
    • Wolff-Parkinson-White syndrome (WPW syndrome, a frequent cardiac arrhythmia in young people that is triggered by an electrical circuit between the auricles and the ventricles.)
    • Ventricular reserve rhythm after failure or blockage of sinus nodes or AV nodes.

Symptoms

A cardiac arrhythmia can also be seen when feeling the pulse wave, for example on the wrist. The pulse can really race, go very slowly or bump irregularly, be hard or flat and weakly palpable, and sometimes it can hardly be felt, if at all. Depending on the severity of the heart damage, shortness of breath, disorientation, dizziness, and temporary speech and vision disorders are possible. Very severe cardiac arrhythmias can lead to loss of consciousness or even death.

An overview of the symptoms of cardiac arrhythmias

    • slow, fast, or stumbling heartbeat (palpitations, palpitations)
    • Stopping the heartbeat (palpable pause in beat)
    • Feeling the heartbeat – sometimes up to the throat (palpitations)
    • Pulse changes (racing, slow, hard, soft, weak, or barely noticeable)
    • Heart pain, chest tightness (angina pectoris)
    • temporary speech and vision disorders
    • Difficulty breathing, disorientation, dizziness, drowsiness, confusion
    • Seizure, collapse, loss of consciousness.

Complications from cardiac arrhythmias

Arrhythmias can lead to dangerous complications. Vascular occlusions (embolisms), heart attacks, strokes, increasing heart failure or sudden cardiac death are particularly feared.

Causes

The cause of an arrhythmia can be in the heart itself or it can be a disease outside the heart. For example, febrile infectious diseases are often accompanied by a heartbeat that is too fast. An underactive thyroid usually causes a slow heartbeat.

Furthermore, electrolyte deficiencies (such as potassium deficiency or calcium deficiency) or an excess of minerals (such as potassium excess) can trigger cardiac arrhythmias of all kinds. For some people, eating 6 bananas is enough to cause cardiac arrhythmias. Because bananas contain a lot of potassium.

There are also congenital disorders of the cardiac excitation or everyday situations that change the heart rhythm (for example excessive alcohol or coffee consumption). Heart diseases that cause irregular heartbeat include:

Other diseases that can cause irregular heartbeat to include:

    • Coronary heart disease (CHD)
    • Heart attack
    • Heart muscle diseases (called cardiomyopathies)
    • Inflammation of the heart (myocarditis or endocarditis)
    • Heart or heart valve defects (such as aortic stenosis or mitral valve regurgitation)
    • congenital or acquired disorders of the cardiac excitation (for example Wolff-Parkinson-White syndrome, WPW syndrome for short).
    • high blood pressure
    • low blood pressure
    • Thyroid dysfunction (such as hyperthyroidism and hypothyroidism)
    • Electrolyte imbalances such as potassium deficiency
    • febrile infectious diseases such as mumps, measles, rubella
    • severe bloating (meteorism)

Hypersensitive carotid sinus in carotid sinus syndrome. The carotid sinus is a receptor on the main artery in the neck that can be irritated by pressure (for example when shaving, by a tight scarf or collar, or when the head is overstretched). As a result, the heartbeat slows down so much that the person affected sometimes passes out.

The following situations can trigger cardiac arrhythmias:

    • Fear, anger, nervousness
    • emotional stress and physical strain
    • excessive consumption of caffeine or teine ​​(coffee, tea, or cola)
    • excessive alcohol consumption
    • Smoke
    • Use of drugs or other poisons
    • Taking medication (e.g. side effects of thyroid hormones or antidepressants).

Examination

The typical complaints and previous or concomitant illnesses point the doctor to the diagnosis of cardiac arrhythmia. To confirm the diagnosis, the doctor will listen to your heart and measure your pulse, followed by a resting electrocardiogram (resting ECG) and, if necessary, a stress ECG. As a rule, these examinations are sufficient to determine cardiac arrhythmias.

Treatment

The doctor decides on an individual basis whether a cardiac arrhythmia needs treatment at all. Sometimes cardiac arrhythmias do not require treatment. Otherwise, the therapy depends on the type and cause of the cardiac arrhythmia. If illnesses are responsible for the disturbed heartbeat sequence, these must first be treated. There are many treatment approaches for cardiac arrhythmias themselves.

Drug Therapy For Cardiac Arrhythmias

Drugs for arrhythmias are called antiarrhythmics. Active ingredients from the following groups are used to treat cardiac arrhythmias with drugs:

    • Class I antiarrhythmics: sodium channel blockers such as ajmaline or quinidine
    • Class II antiarrhythmics: beta-blockers, e.g. bisoprolol, nebivolol, or metoprolol
    • Class III antiarrhythmics: potassium channel blockers, e.g. amiodarone, dronedarone or sotalol
    • Class IV antiarrhythmics: calcium antagonists, such as diltiazem and verapamil.

Other antiarrhythmics are:

    • Adenosine (is often used for the acute therapy of cardiac arrhythmias of the AV node)
    • Digitalis glycosides (strengthen the heart muscles, typical representatives are digoxin and digitoxin)
    • Parasympatholytics (such as atropine and ipratropium bromide)
    • Sympathomimetics (such as adrenaline and noradrenaline)
    • If channel inhibitors (a new group of active substances with the only representative so far ivabradine)

Cardioversion To Restore Normal Heart Rhythm

Cardioversion is designed to restore the heart’s normal sinus rhythm. This rhythmization is mainly used as an emergency treatment for ventricular flutter, ventricular fibrillation, and supraventricular or ventricular tachycardias. Cardioversion can be medicated or electrically (with the help of a defibrillator or cardiac shock). A strong current surge interrupts the electrical activity of the heart. This time-out allows the sinus node to resume its function and then rhythmically pace the heartbeat.

Ablation In Cardiac Arrhythmias

In the case of cardiac arrhythmias such as WPW syndrome, AV node reentry tachycardias or with certain ventricular tachycardias, high-frequency current ablation can be useful. The starting point of the cardiac arrhythmia or additional conduction pathways (as in the WPW syndrome) is obliterated by electricity via a cardiac catheter.

Pacemaker For Cardiac Arrhythmias

Sometimes a pacemaker (Pacer, Pacemaker) is implanted if the heartbeat is too slow. In the case of life-threatening cardiac arrhythmias, the use of an implantable cardioverter-defibrillator (ICD) may be necessary to prevent cardiac arrest.

The pacemaker works like a pulse generator. It monitors the heartbeat and gives electrical impulses to the heart if it beats too slowly. The cardioverter-defibrillator is slightly larger than the pacemaker and monitors the heart rhythm. Depending on the rhythm disturbance, electrical impulses are emitted and over-or under-stimulation corrected. If necessary, cardiac shock therapy is carried out: defibrillation.

Both devices are implanted under the collarbone during a minor surgical procedure. Electrodes connect the devices to the heart. If the heartbeat drops too much, the pacemaker steps in. An implantable cardioverter-defibrillator (ICD) is used, among other things, for atrial flutter and atrial fibrillation as well as for ventricular fibrillation.

How Does A Corona Test Actually Work?

Who will determine if I need to be tested? Where can I get tested? How does the corona test work? And how meaningful are the results? Under what conditions are testing at all?

For the official test for infection with the SARS-CoV-2 coronavirus, two conditions must generally be met. On the one hand, there must be symptoms (from a mild cold to signs of pneumonia) that justify the suspicion of an infection. On the other hand, there must have been contact with a verifiably infected person within 14 days of the onset of symptoms.

Tests are also possible in people with previous illnesses (see also risk groups: Who is most at risk from COVID-19?) Or if respiratory problems (and/or fever) worsen. The decision about this is ultimately made by the attending physician.

It is also possible to test who comes into contact, professionally or on a voluntary basis, with people who are at high risk of a serious disease course with COVID-19.

Until recently, the combination of cold symptoms and staying in an official corona risk area was considered a sufficient requirement for the test. Since April 10th, however, the Robert Koch Institute has no longer identified any risk areas due to the worldwide spread of SARS-CoV-2. The RKI recommends that returnees to Germany go into voluntary quarantine for 14 days.

Where can I do a corona test?

Official corona tests are mainly done in hospitals or specially set up test centers. Sometimes doctors in private practice also offer the corona test. Health authorities also carry out the test on-site, especially for the elderly and/or people with restricted mobility.

If you suspect a corona infection, you should not go to the doctor, but first, inquire by phone. Nationwide, you can call the medical on-call service. The employees can best explain to you how the corona test organization is regulated in your place of residence.

How Does A Corona Test Actually Work

What is done with the corona test to detect SARS-CoV-2?

In the corona test for the detection of SARS-CoV-2, a swab is taken from the mouth, nose, and throat with a cotton swab. Occasionally sputum is saved as a sample.

These samples are then examined in a laboratory. In the meantime (April 10th) these samples can also be evaluated in many hospitals.

How are the coronaviruses detected in the smear?

The common corona test is a so-called PCR test. PCR stands for a polymerase chain reaction, i.e. polymerase chain reaction. PCR tests are considered to be the safest method for detecting viruses such as SARS-CoV-2. Polymerases are very specific proteins that are involved in the construction of the genetic code, DNA. The test can detect even the tiniest amounts of the Coronavirus genetic material.

How safe is the result of the corona test procedure?

The test results are not entirely certain. There can be both false positives and false negatives. Therefore, a first positive test is checked by a second test.

False-negative results are usually checked if the symptoms or the circumstances of possible infection (return from severely affected countries, contact with sick people, or high-risk groups) give a cause.

Sometimes samples are taken incorrectly, damaged during transport, or incorrectly processed in the laboratory.

Are corona rapid tests from the Internet recommended?

The corona rapid tests, which are mainly offered on the Internet, are generally not a PCR test for the detection of viral genetic material, but rather tests that are intended to detect antibodies against SARS-CoV-2 in the blood. Reliable antibody tests play a major role in the therapy of corona because they demonstrate immunity to SARS-CoV-2.

For private use, corona antibody rapid tests from the Internet are not a recommended alternative.

The rapid tests available to date are not fully developed and very likely often give false results – false positive as well as a false negative. Such test results are worthless and do not provide any security. In addition, one can assume that by no means all of the corona rapid tests offered on the Internet come from reputable providers.

How Dangerous Is Covid-19 For Children?

How Dangerous Is Covid-19 For Children?. According to the Robert Koch Institute, corona infections in children are mostly mild or unnoticed. At the same time, however, the experts agree that there is so far too little data to make a scientifically tenable statement about the COVID-19 risk in children. The reason for this is simple: Parents understandably do not bring their children to the doctor or hospital if things go slightly or unnoticed. Therefore, children are rarely tested. The proportion of patients who tested positive has so far been around 2 percent for children and adolescents and 6 percent for young adults up to the age of 20 (see sources, section 2). However, it is not currently possible to say with certainty whether this corresponds to the actual prevalence.

More frequent severe courses in children with previous illnesses

So it is currently not possible to answer with final certainty whether COVID-19 is actually almost always mild in children. But there is much to be said for it. Nevertheless, there are also difficult courses for children. According to the RKI, infants and toddlers are treated as inpatients for COVID-19 more often than other children and adolescents. Children with pre-existing conditions such as cardiovascular diseases or diabetes make up around a quarter of the children admitted to the hospital and half of all children who had to be treated in an intensive care unit because of COVID-19. According to the German Society for Pediatric Infectious Diseases (22), there was only one death associated with COVID-19 in this patient group in Germany until May 18.

Why is COVID-19 often symptom-free or mild in children?

This question cannot be answered at the moment, as the relevant research has not yet been possible. Experts suspect that the child’s immune system, which is not fully developed, enables a broader non-specific defense system than the “ready-made” immune system of adults. Another possibility would be that the child’s cells offer the virus fewer docking options because the corresponding binding sites (receptors) for the virus are not yet developed or are less strongly developed in the child’s cells.

Are children infected more easily than adults?

According to the current state of research, it looks like children are actually less likely to become infected with Sars-CoV-2 than adults. As with many other questions about corona infections, this question cannot currently be answered conclusively.

According to the RKI, studies come to very different results. In the majority of studies, however, the infection rate in children is significantly lower than that of adults. A study from China puts the infection rate in children under 15 years of age at a third of the risk for people between the ages of 15 and 64. The study “Changes in contact patterns shape the dynamics of the COVID-19 outbreak in China” was published by Science at the end of April.

How Dangerous Is Covid-19 For Children

How contagious are children to other children or adults?

The study situation is currently not clear on this question either. Germany’s leading virologist Christian Drosten published an evaluation of the laboratory tests at the Berline Charité at the end of April. According to this, the viral load of infected children is essentially as great as that of adults. Therefore, it could be possible that children are just as contagious as adults, Drosten concludes. At the same time, he admits that the number of children recorded in this analysis is very small. In his podcast, Drosten says “You should actually have ten times as many children, but we don’t have that many”.

Study in Baden-Württemberg: Children are not drivers of infections

The state of Baden-Württemberg had 2,500 children aged up to 10 years and one parent each tested for corona infections and antibodies. The complete results of this investigation by the university hospitals in Heidelberg, Freiburg, and Tübingen are not yet available. According to the state government, however, the interim results show that children are significantly less contagious and infectious than adults. The difference is significant, said Prime Minister Winfried Kretschmann (Greens) during a press conference on May 26th. And further: “We can rule out that children are drivers of the infection process”. These are reliable interim results with a stable trend “.

Professional societies: Children do not play a prominent role in the spread

In their joint statement “Children and adolescents in the COVID-19 pandemic”, 4 medical societies had previously assessed the study situation. They come to the conclusion that the risk of infection in children is significantly lower than that of adults. Accordingly, children do not play a prominent role in the spread of COVID-19. Rather, the infection in the family usually occurs through infected adults.

Do parents need to be concerned about the number of cases of Atypical Kawasaki Syndrome?

In the past few weeks, reports of severe inflammation in children with COVID-19 have created great concern among many parents. Accordingly, especially in the USA, Italy, Spain, France, and Switzerland, a noticeable number of children showed severe symptoms that resemble Kawasaki syndrome.

The German Society for Pediatric Infectious Diseases (DGPI) and the German Society for Pediatric Cardiology and Congenital Heart Defects (DGPK) point out in a joint statement that the reported cases do not always correspond to the typical clinical picture of Kawasaki syndrome. Therefore, in their opinion, the experts speak of an excessive inflammatory reaction with inflammation of the blood vessels (vasculitis). Such hyper inflammation syndromes were already well known before COVID-19. There is currently no evidence that infections with Sars-CoV-2 are the trigger for the corresponding symptoms.

At the same time, the experts point out that hyper inflammation syndromes can be treated “very well with cortisone or other immunosuppressants and immunoglobulins”. Therefore, there is no reason for parents to be concerned about the number of cases of atypical Kawasaki syndrome.

New evidence of a lower risk of infection for and by children

Update from June 17th

The University Hospitals of Freiburg, Heidelberg, Tübingen, and Ulm have now presented the first results of the study commissioned by the State of Baden-Württemberg on the risk of infection in children. According to the medical director of the children’s clinic at Ulm University Hospital, children are not to be seen as drivers of the wave of corona infections. However, the cause is still unknown, said Klaus-Michael Debatin on June 16 at a press conference. It may be because children have fewer binding sites (ACE receptors) to which the virus can dock. But it is also possible that the child’s immune system successfully combats SARS-CoV-2 in the nasopharynx.

For the study, the doctors tested around 2,500 children under 10 years of age and one parent each for SARS-CoV-2 and COVID-19 antibodies from April 22 to May 15. Of the 5,000 participants, only one parent-child pair was infected during the survey period. Antibodies could be detected in 64 people – 45 adults and 19 children.

Low number of infections in the families studied

The scientists summarize: “The preliminary analysis of the study shows that the most important results are that only a small number of infections occurred in the families examined and that children apparently not only contract COVID-19 less, which has been known for a long time, but also less often be infected by the SARS-CoV-2 virus. ”

The scientists point out that they could make statements about whether children infected their parents or parents infected their children. The study also did not examine how infectious children are in principle. Like many other studies in connection with Corona, the study has not yet been reviewed by experts.