Endocrine, nutritional, and metabolic diseases (E00-E90).
- Amyloidosis – extracellular (“outside the cell”) deposits of amyloids (degradation-resistant proteins) that can lead to cardiomyopathy (heart muscle disease), neuropathy (peripheral nervous system disease), and hepatomegaly (liver enlargement), among others.
- Hashimoto’s thyroiditis – autoimmune disease that leads to chronic inflammation of the thyroid gland.
- Hyperkalemia (excess potassium)
- Hypercapnia – too much carbon dioxide in the blood.
- Hypothyroidism (underactive thyroid gland)
- Metabolic acidosis – metabolic hyperacidity.
- Myxedema – pasty (puffy; bloated) skin showing non-push-in, doughy edema (swelling) that is not position-dependent; in the facial area and peripherally; occurring primarily on the lower legs; usually the result of hypothyroidism (underactive thyroid gland)
- Severe hypoxia (oxygen deficiency).
Cardiovascular system (I00-I99)
- Acute coronary syndromes (AKS; acute coronary syndrome, ACS) – sinus bradycardia if posterior wall/inferior infarct → pacing should be discussed
- Atrioventricular block (AV blocks II° and III°).
- Bradyarrhythmia associated with atrial fibrillation (prevalence (incidence of disease): 6.5%)
- Bradycardia-induced tachyarrhythmias (long-QT syndrome, (LQTS); belongs to the group of ion channel diseases (channelopathies); note: QTc cut-off is 480 ms; screening for long-QT should be performed starting at a QTc of 460 ms if clinically suspicious syncope/s have occurred).
- Bradycardia–tachycardia syndrome – bradycardic phases of the heartbeat (< 60 beats per minute) alternating with tachycardic phases (> 100 beats per minute); belongs to the sinus node disorders.
- Hyperreactive carotid sinus
- Hypertensive crisis – severely elevated blood pressure with values above 230/130 mmHg.
- Hypervagotonia – overactivity of the vagus nerve.
- Intracranial hemorrhage (bleeding within the skull; parenchymal, subarachnoid, sub- and epidural, and supra- and infratentorial hemorrhage)/intracerebral hemorrhage (ICB; cerebral hemorrhage).
- Intraventricular block
- Sick sinus syndrome (sinus node disease)
- Sinuatrial block (SA block).
Infectious and parasitic diseases (A00-B99).
- Brucellosis (Malta fever) – infectious disease transmitted from animals to humans.
- Dengue fever
- Yellow fever
- Influenza (flu)
- Tetanus (tetanus)
- Typhoid fever – infectious disease with severe diarrhea.
Liver, gallbladder and bile ducts – Pancreas (pancreas) (K70-K77; K80-K87).
- Liver disease in advanced stages
Neoplasms (C00-D48)
- Brain tumors
Psyche – nervous system (F00-F99; G00-G99)
- Anorexia nervosa (anorexia nervosa)
- Cerebral edema (swelling of the brain)
Symptoms and abnormal clinical and laboratory findings not elsewhere classified (R00-R99).
- Emesis (vomiting)
- Hypothermia (hypothermia)
- Icterus (jaundice)
Injuries, poisonings, and certain other sequelae of external causes (S00-T98).
- Intracranial hemorrhage (cerebral hemorrhage) → intracranial pressure ↑
- Poisoning
Medication
- Acetylcholinesterase inhibitors (donezepil, galantamine, neostigmine, rivastigmine).
- Alpha-2 agonist (tizanidine).
- Antiarrhythmic drug
- Ic antiarrhythmics (flecainide, propafenone).
- Class II antiarrhythmics (atenolol, bisoprolol, metoprolol, propranolol).
- Class III antiarrhythmics (amiodarone, sotalol)Concurrent therapy with the hepatitis C agent sofosbuvir (HCV polymerase inhibitor) and the antiarrhythmic agent amiodarone may potentially cause life-threatening bradycardia
- Antidepressants (citalopram).
- Antiepileptic drugs
- Functionalized amino acid (lacosamide).
- Antihypertensives
- Methyldopa
- Imidazoline (clonidine)
- Beta-blockers, local (betaxolol, timolol) [eye drops].
- Beta blockers, systemic (acebutolol, atenolol, betaxolol, bisoprolol, carvedilol, celiprolol, esmolol, metoprolol, nadolol, nebivolol, oxprenolol, pindolol, propranolol)
- Calcium antagonists (calcium channel blockers).
- Cholinesterase inhibitor (Distigmine).
- Digitalis – digoxin
- Cardiac glycosides (ß-acetyldigoxin, ß-methyldigoxin, digoxin, digitoxin).
- Immunosuppressants (thalidomide).
- Immunotherapeutics (fingolimod)
- Local anesthetics (lidocaine, mepivacaine, procaine).
- Opiates or opioids (alfentanil, apomorphine, buprenorphine, codeine, dihydrocodeine, fentanyl, hydromorphone, loperamide, morphine, methadone, nalbuphine, naloxone, naltrexone, oxycodone, pentazocine, pethidine, piritramide, remifentanil, sufentanil, tapentadol, tilidine, tramadol).
- Muscle relaxants (succinylcholine, tizanidine).
- Lithium
- Parasympathomimetics
- Indirect parasympathomimetics (cholinesterase inhibitors): alkylphosphates, distigmine, donepezil, galantamine, neostigmine, physostigmine, pyridostigmine, rivastigmine, tacrine
- Sinus node inhibitor (If-channel inhibitors or If-inhibitors): ivabradine.
- Cytostatic drugs (paclitaxel).
Environmental pollution – intoxications (poisonings).
- Organophosphates (E605)
Further
- Teenagers
- Higher age
- Fasting → increased vago and reduced sympathetic tone → bradycardia.
- Resting/sleeping (45-55 beats per minute).
- Athlete
