Myocardial Infarction, Aortic Aneurysm and Aortic Dissection PDF

Myocardial Infarction, Aortic Aneurysm and Aortic Dissection Presenters : Shanice Mupamombe Princess Chakweya Regina Sakuwema Moderator: Dr Mwaanga Contents Introduction Relevant Anatomy Etiology Risk factors Pathophysiology Clinical Manifestations Physical...

Myocardial Infarction, Aortic Aneurysm and Aortic Dissection Presenters : Shanice Mupamombe Princess Chakweya Regina Sakuwema Moderator: Dr Mwaanga Contents Introduction Relevant Anatomy Etiology Risk factors Pathophysiology Clinical Manifestations Physical Examinations Investigations Differential Diagnosis Treatment and Management Complications  Introduction Myocardial infarction Necrosis of the heart muscle resulting from ischaemia. Also known as a heart attack. Aortic Aneurysm A congenital or acquired dilation of the lumen of the thoracic or abdominal aorta Aortic Dissection A tear or breach in the of the aortic wall allows arterial blood to enter between the intima and media creating a false lumen alongside the existing true lumen Relevant Anatomy Relevant Anatomy : Blood Supply to the Heart Relevant Anatomy: Blood Supply to the Heart  Relevant Anatomy : The Aorta ▪ The aorta is divided into the thoracic aorta and the abdominal aorta. ▪ The thoracic aorta has 4 parts : 1) Aortic root 2) Ascending aorta 3) Aortic arch 4)Descending aorta Relevant Anatomy: Wall of the Aorta Etiology  Etiology : Myocardial Infarction A Myocardial infarction is caused by acute occlusion of the coronary artery due to : 1. Atherosclerosis 2. Thrombosis within the coronary artery where an arthesclerotic plaque has ruptured and eroded 3. Embolism from mural thrombi 4. Coronary artery vasospasm 5. Disorders of small intramyocardial arterioles including vasculitis, amyloid deposition or stasis (as in sickle cell disease).  MI Names According to Location Left anterior descending occlusion: -Anterior wall MI - AKA Widow maker (highest mortality rate) Right coronary artery occlusion: -Inferior wall MI Left Circumflex occlusion -Lateral or Posterior MI  Types of Myocardial infarctions STEMI A ST-segment elevation myocardial infarction involves a complete blockage of the coronary artery NSTEMI A non-ST-segment elevation myocardial infarction involves a partial blockage of the coronary artery  Etiology: Aortic Aneurysm Many factors contribute to the development of an aortic aneurysm but the key factors include: 1. Atherosclerosis ( which is the most common cause) 2. Genetic predisposition : conditions like Marfan syndrome, Ehlers - Danlos syndrome, and Turner syndrome 3. Hypertension : chronic high blood pressure causes mechanical stress and accelerates aortic degeneration 4. Trauma 5. Hyperlipidemia 6. Infectious diseases: Syphilis. Tuberculosis and Salmonellosis 7. Vasculitis 8. Age-related degeneration Etiology: Aortic Aneurysms  Etiology: Aortic Dissections 1. Hypertension 2. Genetic disorders e.g. Marfan Syndrome and EDS 3. Atherosclerosis 4. Coarctation 5. Trauma 6. Aortic valve abnormalities e.g bicuspid aortic valve 7. Previous cardiac surgery e.g. Aortic valve replacement 8. Inflammatory diseases e.g vasculitis of the aorta 9. Iatrogenic factors e.g. Cardiac catheterisation or Intra-aortic balloon pumping CLASSIFICATION OF AORTIC DISSECTIONS Risk factors Deep vein thrombosis Diabetes Obesity Smoking Old age; 60 years and above Gender Stress High blood pressure Sedentary Lifestyle Cardiac tamponade Aortic Dissection High Cholesterol Family History Pathophysiology  Pathophysiology of a Myocardial Infarction 1. Atherosclerosis 2. Plaque rupture 3. Thrombosis: platelet aggregation and coagulation cascade 4. Ischemia of cardiac tissue 5. Necrosis of cardiac tissue due to prolonged ischemia 6. Inflammation 7. Loss of structure and function of the affected area Pathophysiology of Aortic Aneurysm Structural Changes in the Aortic Wall Inflammation Atherosclerosis Hemodynamic Factors Pathophysiology of Aortic dissection Initiation of the Intimal Tear Propagation of the Dissection Hemodynamic and Structural Factors Inflammation and Autoimmune Diseases Clinical presentation Clinical presentation : Myocardial Infarction Symptoms Signs Chest Pain Paleness or Cyanosis Shortness of Breath Changes in Heart Rate Sweating Distress: Signs of acute distress, Fatigue Weak or irregular pulses Clinical Presentation: Thoracic Aortic Aneurysm Symptoms Signs Chest Pain Dysphagia (Difficulty Swallowing) Back Pain Stridor Cough or Shortness of Breath Hoarseness Clinical presentation: Abdominal Aortic Aneurysm Symptoms Signs Abdominal Pain Pulsatile Abdominal Mass Abdominal Tenderness Back Pain Abdominal Bruit Back Tenderness Clinical Presentation : Aortic Dissection Symptoms Signs Severe chest pain Tachycardia Abdominal pain Pulse Deficit Nausea and vomiting Neurological Deficit Shortness of breath Hypotension Physical Examination  Physical Examination Inspection Palpation Auscultation Investigations Investigations: Myocardial Infarction Electrocardiogram (ECG) Primary Test: Essential for diagnosing MI. ST-Segment Elevation: Indicates ST-elevation myocardial infarction (STEMI). ST-Segment Depression or T-Wave Inversion: Indicates non-ST-elevation myocardial infarction (NSTEMI). Pathological Q Waves: Suggests previous or ongoing infarction Investigations: Myocardial Infarction Echocardiogram: sound waves to create pictures of the heart. This common test can show blood flow through the heart and heart valves. Investigations : Myocardial Infarction.Chest X-ray Cardiomegaly (Enlarged Heart)May indicate pre-existing heart disease or heart failure as a complication of MI. Investigations : Myocardial infarction Blood test Coronary Angiography Magnetic Resonance Imaging (MRI) Investigations: Aortic Aneurysm Imaging Studies: Computed Tomography (CT) Scan Magnetic Resonance Imaging (MRI) X-ray Aortic Angiography Laboratory Tests: Blood Tests Investigations : Aortic dissection Imaging Studies: Computed Tomography (CT) Scan Magnetic Resonance Imaging (MRI) Aortography Chest X-ray Laboratory Tests: Complete Blood Count (CBC) Cardiac Biomarkers Differential Diagnosis Differential Diagnosis: Myocardial Infarction Angina pectoris Pulmonary embolism Aortic dissection Gastroesophageal reflux disease (GERD) Pericarditis Differential Diagnosis: Aortic aneurysm Aortic dissection Myocardial infarction Pulmonary embolism Pericarditis Pneumothorax Differential diagnosis: Aortic dissection Myocardial infarction Aortic aneurysm Pulmonary embolism Pericarditis Pneumothorax Management and Treatment Management and Treatment: Myocardial infarction (Non- Surgical) Pharmaceutical Non - pharmaceutical Antiplatelet Agents: Aspirin Percutaneous coronary intervention (PCI), Anticoagulants: Heparin Cessation of smoking Nitroglycerin: Sublingual or Alcohol intake should stop Intravenous Diet change Opioids: Morphine Stress management Management and Treatment: Myocardial infarction (Surgical) Coronary Artery Bypass Grafting (CABG) Percutaneous Mechanical Circulatory Support: 1. Intra-aortic Balloon Pump (IABP): Increases coronary perfusion and decreases cardiac workload. 2. Impella Device: Provides direct mechanical support to the left ventricle, improving cardiac output. Management and Treatment: Aortic Aneurysm (Non- surgical) Pharmaceutical Non-pharmaceutical Antihypertensive Agents: Blood Pressure Management 1. Beta-Blockers (e.g., Metoprolol, Atenolol) Avoid Straining Activities 2. ACE Inhibitors (e.g., Lisinopril, Ramipril) Dietary Changes Statins (e.g., Atorvastatin, Smoking Cessation Rosuvastatin) Analgesics (e.g., Acetaminophen, NSAIDs Management and Treatment: Aortic Aneurysm (Surgical) Open Surgical Repair Endovascular Aneurysm Repair Management and Treatment: Aortic dissection (Non-surgical) Pharmaceutical Non-Pharmaceutical Pain Management: Analgesics, eg: Acetaminophen, Dietary Changes Opioids (e.g., Morphine) Blood Pressure Management Angiotensin II Receptor Blockers, eg: Losartan, Moderate Exercise Valsartan. Quit Smoking Management and Treatment: Aortic dissection (Surgical) Type A Aortic Dissection: Open Surgical Repair Type B Aortic Dissection: Endovascular Repair Complications Complications: Myocardial Infarction Heart failure Ventricular fibrillation Atrial fibrillation Pericarditis Cardiogenic shock ischemia Complications: Aortic Aneurysm Hemorrhage Hypovolemic shock Aortic dissection Compression of nearby structures:trachea or bronchi,esophagus and nerves. Stroke Complications: Aortic dissection Aortic rupture Organ ischemia Coronary artery involvement Cardiac tamponade Infection and sepsis  References ▪ Ralston, S., Penman, I. D., Stracha, M. & Hobson, R. P., 2018. Davidson's Principles and Practice of Medicine. Twenty-third ed. Edinburg: Elsevier. ▪ Centers for Disease Control and Prevention (2022) 'Aortic Aneurysm', CDC. Available at: https://www.cdc.gov/heartdisease/aortic_aneurysm.htm ▪ National Heart, Lung, and Blood Institute (2021) 'What is a heart attack?', NHLBI. Available at: https://www.nhlbi.nih.gov/health-topics/heart-attack ▪ Mayo Clinic (2023) 'Aortic dissection: Symptoms and causes', Mayo Clinic. Available at: https://www.mayoclinic.org/diseases-conditions/aortic- dissection/symptoms-causes/syc-20369440 THANK YOU ANY QUESTIONS?