HypocalcemiaHypocalcemia is a medical condition characterized by low calcium levels in the blood serum. The normal range of blood calcium is typically between 2.1–2.6 mmol/L (8.8–10.7 mg/dL, 4.3–5.2 mEq/L) while levels less than 2.1 mmol/L are defined as hypocalcemic. Mildly low levels that develop slowly often have no symptoms. Otherwise symptoms may include numbness, muscle spasms, seizures, confusion, or cardiac arrest. The most common cause for hypocalcemia is iatrogenic hypoparathyroidism.
ProcainamideProcainamide (PCA) is a medication of the antiarrhythmic class used for the treatment of cardiac arrhythmias. It is classified by the Vaughan Williams classification system as class Ia; thus it is a sodium channel blocker of cardiomyocytes. In addition to blocking the INa current, it inhibits the IKr rectifier K+ current. Procainamide is also known to induce a voltage-dependent open channel block on the batrachotoxin (BTX)-activated sodium channels in cardiomyocytes.
TerfenadineTerfenadine is an antihistamine formerly used for the treatment of allergic conditions. It was brought to market by Hoechst Marion Roussel (now Sanofi) and was marketed under various brand names, including Seldane in the United States, Triludan in the United Kingdom, and Teldane in Australia. It was superseded by fexofenadine in the 1990s due to the risk of a particular type of disruption of the electrical rhythms of the heart (specifically cardiac arrhythmia caused by QT interval prolongation) and has been withdrawn from markets worldwide.
Antiarrhythmic agentAntiarrhythmic agents, also known as cardiac dysrhythmia medications, are a group of pharmaceuticals that are used to suppress abnormally fast rhythms (tachycardias), such as atrial fibrillation, supraventricular tachycardia and ventricular tachycardia. Many attempts have been made to classify antiarrhythmic agents. Many of the antiarrhythmic agents have multiple modes of action, which makes any classification imprecise. Cardiac action potential The cardiac myocyte has two general types of action potentials: conduction system and working myocardium.
ErythromycinErythromycin is an antibiotic used for the treatment of a number of bacterial infections. This includes respiratory tract infections, skin infections, chlamydia infections, pelvic inflammatory disease, and syphilis. It may also be used during pregnancy to prevent Group B streptococcal infection in the newborn, as well as to improve delayed stomach emptying. It can be given intravenously and by mouth. An eye ointment is routinely recommended after delivery to prevent eye infections in the newborn.
Drug interactionDrug interactions occur when a drug's mechanism of action is affected by the concomitant administration of substances such as foods, beverages, or other drugs. The cause is often inhibition of, or less effective action, of the specific receptors available to the drug. This influences drug molecules to bind to secondary targets, which may result in an array of unwanted side-effects. The term selectivity describes a drug’s ability to target a single receptor, rendering a predictable physiological response.
Premature ventricular contractionA premature ventricular contraction (PVC) is a common event where the heartbeat is initiated by Purkinje fibers in the ventricles rather than by the sinoatrial node. PVCs may cause no symptoms or may be perceived as a "skipped beat" or felt as palpitations in the chest. PVCs do not usually pose any danger. The electrical events of the heart detected by the electrocardiogram (ECG) allow a PVC to be easily distinguished from a normal heart beat.
Implantable cardioverter-defibrillatorAn implantable cardioverter-defibrillator (ICD) or automated implantable cardioverter defibrillator (AICD) is a device implantable inside the body, able to perform defibrillation, and depending on the type, cardioversion and pacing of the heart. The ICD is the first-line treatment and prophylactic therapy for patients at risk for sudden cardiac death due to ventricular fibrillation and ventricular tachycardia. "AICD" was trademarked by the Boston Scientific corporation, so the more generic "ICD" is preferred terminology.
Left ventricular hypertrophyLeft ventricular hypertrophy (LVH) is thickening of the heart muscle of the left ventricle of the heart, that is, left-sided ventricular hypertrophy and resulting increased left ventricular mass. While ventricular hypertrophy occurs naturally as a reaction to aerobic exercise and strength training, it is most frequently referred to as a pathological reaction to cardiovascular disease, or high blood pressure. It is one aspect of ventricular remodeling. While LVH itself is not a disease, it is usually a marker for disease involving the heart.
Wolff–Parkinson–White syndromeWolff–Parkinson–White syndrome (WPWS) is a disorder due to a specific type of problem with the electrical system of the heart involving an accessory pathway able to conduct electrical current between the atria and the ventricles, thus bypassing the atrioventricular node. About 60% of people with the electrical problem developed symptoms, which may include an abnormally fast heartbeat, palpitations, shortness of breath, lightheadedness, or syncope. Rarely, cardiac arrest may occur.
