Heart Dysfunctions PDF

Komar University of Science and Technology Heart dysfunctionalities Dr. Raneen Subhi MSc Clinical Pharmacy  Content Arrhythmia Coronary artery disease Heart failure Treatment  Arrhyth...

Komar University of Science and Technology Heart dysfunctionalities Dr. Raneen Subhi MSc Clinical Pharmacy  Content Arrhythmia Coronary artery disease Heart failure Treatment  Arrhythmia An arrhythmia (also called dysrhythmia) is an abnormal heartbeat. Arrhythmias can start in different parts of the heart and they can be too fast, too slow, or just irregular. Heart Rate (HR): the frequency of the heartbeat measured by the number of contractions of the heart per minute Tachycardia: HR more than 100 bpm Bradycardia: HR less than 60 bpm Conduction system of the heart  Supraventricular Arrhythmia The common supraventricular tachycardias that often require drug treatment is: 1. Atrial fibrillation (AF) 2. Atrial flutter (AFI) 3. Paroxysmal supraventricular tachycardia (PSVT) 4. Automatic atrial tachycardias  Atrial Fibrillation Characterized by disorganized, rapid, and irregular atrial activation with loss of atrial contraction and with an irregular ventricular rate Atrial rate of 400-600 beats/min and ventricular rate between 120 and 160 beats/min 1. Acute AF (onset within 48 hours) 2. Persistent AF (duration longer than 7 days) 3. Long standing AF (duration longer than 12 months) 4. Permanent AF  Atrial Flutter AFl is characterized by rapid (atrial rate of 270- 330 beats/min) but regular atrial activation. The slower and regular electrical activity results in a regular ventricular response that is in approximate factors of 300 beats/min  Clinical Manifestations Clinical consequences of AF are related to rapid ventricular rates, loss of atrial contribution to ventricular filling, and predisposition to thrombus formation in the left atrial appendage with potential embolization Patients complain of rapid heart rate/palpitations, chest pain, dyspnea, dizziness, and fatigue. Medical emergencies are severe HF (ie, pulmonary edema, hypotension).  General Approaches General treatment goals for symptomatic atrial flutter are similar to those for atrial fibrillation and include the following: Control of the ventricular rate Restoration of sinus rhythm Prevention of recurrent episodes or reduction of their frequency or duration Prevention of thromboembolic complications Minimization of adverse effects from therapy Classification of Antiarrhythmic drugs  Ventricular Rate Control Ventricular rate control to achieve a rate of less than 100 beats per minute is generally the first step in managing atrial fibrillation. Beta-blockers, calcium channel blockers, and digoxin (Lanoxin) are the drugs most commonly used for rate control  Electrical Cardioversion When patients with atrial fibrillation are hemodynamically unstable (e.g., angina, hypotension) and not responding to resuscitative measures, emergency electrical cardioversion is indicated. In stable patients, elective cardioversion is performed after three weeks of warfarin therapy. To prevent thrombus formation, warfarin is continued for four weeks after cardioversion  Maintenance of Sinus Rhythm No structural heart disease (HF, CAD, LVH) First line: dofetilide, dronedarone, flecainide, propafenone, or sotalol Second line: amiodarone Heart failure First line: amiodarone, dofetilide Second line: catheter ablation Coronary artery disease First line: dofetilide, dronedarone, sotalol Second line: amiodarone Persistent symptoms associated with AF remain the most compelling indication for a rhythm-control strategy. Other factors that may favor attempts at rhythm control include difficulty in achieving adequate rate control, younger patient age, tachycardia-mediated cardiomyopathy, the first episode of AF, AF precipitated by an acute illness and patient preference  Ventricular Arrhythmia The common ventricular arrhythmias include: 1. Premature ventricular contractions (PVCs) 2. Ventricular tachycardia (VT) 3. Ventricular fibrillation (VF)  Premature Ventricular Contractions (PVCs) PVCs may be elicited by abnormal automaticity, triggered activity, or reentrant mechanisms Are non–life-threatening and usually asymptomatic Occurs early and the ventricle contracts when it is incompletely filled, patients do not feel the PVC If patients have symptomatic PVCs, chronic drug therapy should be limited to the use of beta blockers  Ventricular Tachycardia (VT) A type of tachycardia that may acutely occur as a result of metabolic abnormalities, ischemia, or drug toxicity, or chronically recur as a paroxysmal form Are three or more consecutive PVCs occurring at a rate of greater than 100 beats/min Precipitated by severe electrolyte abnormalities (hypokalemia or hypomagnesemia), hypoxia, or digoxin toxicity, or (most commonly) may occur in patients presenting with acute MI or myocardial ischemia complicated by HF  Ventricular Tachycardia / Treatment Acute Ventricular Tachycardia If severe symptoms are present, institute synchronized DCC The Rx for patients with mild or no symptoms is IV procainamide, amiodarone, sotalol or lidocaine Deliver synchronized DCC if the patient’s status deteriorates, VT degenerates to VF, or drug therapy fails Sustained Ventricular Tachycardia Implantable Cardioverter-Defibrillator (ICD) Non-sustained VT Four treatment strategies based on symptoms and underlying comorbidities: (a) Conservative (ie, no AAD treatment beyond beta-blockers) (b) Empiric amiodarone (c) Ablation (d) Implantable Cardioverter-Defibrillator ICD  Ventricular Fibrillation (VF) VF is the electrical anarchy of the ventricle resulting in no cardiac output and CV collapse CPR, medications, and defibrillation can be corrective measures to prevent SCD (sudden cardiac death), Advanced Cardiac Life Support (ACLS): Following defibrillation, medications such as epinephrine or amiodarone may be administered as part of the ACLS protocol It is more dangerous than VT Coronary Artery Disease Coronary Artery Disease Types of Acute Coronary disease Risk Factors  Clinical Manifestations ❖ Exertional chest pain is the classic presenting symptom ❖ Rest or the use of sublingual nitroglycerin (SL-NTG) relieves the symptoms (less than 20 minutes; usually 5-10 minutes) ❖ Chest pain is often substernal and may radiate to the right or left shoulder, right or left arm (left more commonly than right), neck, back, or abdomen ❖ Other symptoms that may be present include: nausea, vomiting, and dyspnea  Goal of treatment 1. Elimination of chest pain and return to normal activities 2. Reducing the risk of CV events and mortality 3. Slowing the progression of atherosclerosis and preventing complications 4. Reducing the number of ischemic episodes as well as increasing the amount of exertion or exercise a patient can accomplish  Non- pharmacological treatment 1. Daily physical activity and weight loss 2. Reduce intake of saturated fat (