CARDIOVASCULAR AGENTS - some of the most widely used medications treat conditions of the cardiovascular system - cardiovascular agents include - antianginals - antiarrhythmias - antihypertensives - vasopressors - antihyperlipidemics - thrombolytics - anticoagulants
- used in treating - myocardial infarction (heart attack) - angina - cerebral vascular accident (CVA) / stroke - hyper / hypotension (blood pressure) - congestive heart failure (CHF) - arrhythmias - high cholesterol - blood clots - atreiosclerosis
THE HEART conduction - the heart is a pump that uses complex chemical and electrical processes to function - chemically charged ions stimulate heart muscle to contract and relax systematically (cardiac cycle) - pumps blood through the cardiovascular system - the sinoatrial node (SA) generates the electrical impulse and sets the pace of the heart (stimulates the atria and ventricles) - the atrioventricular node (AV) and Purkinje fibers (located at the base of the heart) transmit the impulse
the heart and circulation - heart is divided into 4 chambers (R/L atria and R/L ventricles) - the R atria receives deoxygenated blood from the body and pumps it to the lungs (pulmonary circulation) - the L atria receives oxygenated blood from the lungs and pumps it to the tissues of the body (systemic circulation) - the myocardium (heart muscle) is supplied with oxygenated blood by the coronary arteries (branch from the aorta and circle back to the heart)
blood clotting - essential function of blood that prevents excessive blood loss from injuries - clotting factors, platelets and healthy blood vessel walls are important in the formation of clots - too much clotting can be dangerous - if a clot (thrombus) is formed in the blood stream, it can be carried to a smaller vessel and block the flow of blood (embolism)
blood pressure - outward pressure of blood against the arteries as it is pumped through the heart - systolic pressure is the maximum pressure as the heart contracts - diastolic pressure is the minimum pressure as the heart relaxes
arrhythmias - normally, the electrical system of the heart causes it to contract (beat) in a regular and organized rhythm - can be graphed by an electrocardiogram (ECG/EKG) - arrhythmia is an abnormal heart rhythm that can interfere with the heart’s ability to pump effectively - tachycardia (fast) - bradycardia (slow) - premature or ectopic beats - flutter and fibrillation
Classes of Cardiovascular Agents antianginals - treat cardiac related chest pain (angina) resulting from ischemic heart disease - lack of oxygen and blood flow to the heart -nitrates, beta-blockers and calcium channel blockers (nitroglycerine / Procardia) antiarrhythmatics - treat irregular heart rhythms - regulate the conduction activity of the heart by inhibiting abnormal pacemaker cells or recurring abN impulses and restoring a normal rhythm - beta-blockers (digoxin, propranolol), drugs that block sodium, potassium ion and calcium channels
antihypertensives - reduce a sustained elevation in blood pressure - factors affecting blood pressure include stress, blood volume, arterial narrowing, age, gender and general condition of health - furosemide (Lasix) and altace (Ramipril) vasopressors - increase blood pressure through fluid replacement or dopamine (Dobutamine) antihyperlipidemics - lower high levels of cholesterol that can lead to vessel blockage - simvastatin and provastatin thrombolytics (dissolve blood clots) / anticoagulants (prevent clot formation)
further clarification… beta-blockers - reduce oxygen demands of the heart muscle calcium channel blockers - relax the heart by reducing heart conduction diuretics - decrease blood pressure by decreasing blood volume - increase the elimination of salts and water through urination ACE inhibitors - “pril” drugs relax the blood vessels vasodilators - relax and expand the blood vessels