Cardio 21-25 Flashcards
- What is atrial fibrillation?
Atrial fibrillation is an irregular and often rapid heart rate that can increase the risk of strokes, heart failure, and other heart-related complications. During AF, the atria beat irregularly and out of coordination with the ventricles, leading to quivering.
What is the primary pathologic change in atrial fibrillation?
The primary pathologic change in atrial fibrillation is progressive fibrosis of the atria, primarily due to atrial dilation. This may be influenced by genetic factors and inflammation.
What are some common causes of atrial fibrillation?
Common causes include:
Valvular diseases (mitral stenosis, mitral regurgitation)
Hypertension
Congestive heart failure
Viral infections
How does atrial dilation contribute to atrial fibrillation?
Atrial dilation increases stress on cardiomyocytes, leading to tissue heterogeneity where cells develop different properties, causing unpredictable conduction in the atria.
What are the types of atrial fibrillation?
Paroxysmal AF: Comes and goes (< 1 week), self-terminating. Diagnosed by Holter monitoring.
Persistent AF: Repeated paroxysmal AF (> 1 week), not self-terminating.
Permanent AF: Lasts over 1 year and cannot be terminated. Diagnosed by ECG.
What are the common symptoms of atrial fibrillation?
Symptoms include:
Heart palpitations
Shortness of breath
Weakness
Fatigue
Dizziness
Chest pain
What is the most serious consequence of atrial fibrillation?
The most serious consequence of atrial fibrillation is thrombus formation due to stasis in the atria, leading to embolization, particularly to the cerebral circulation, which can result in ischemic stroke.
What scoring systems are used to assess thromboembolic risk in atrial fibrillation?
The CHADS2 score and its updated version, the CHA2DS2-VASc score, are used to estimate the risk of stroke in patients with non-rheumatic atrial fibrillation.
How is the CHADS2 and CHA2DS2-VASc score utilized?
These scores help determine whether treatment with anticoagulation therapy or antiplatelet therapy is required. A high score indicates a greater risk of stroke, while a low score indicates a lower risk.
CHADS2
CHA2DS2-VASc
What is Buerger’s disease?
Buerger’s disease, also known as Thromboangiitis obliterans, is a recurring progressive inflammation and thrombosis of medium arteries and veins of the hands and feet. It is strongly associated with tobacco use, primarily from smoking.
Who is most commonly affected by Buerger’s disease?
Buerger’s disease typically occurs in young males (under 40 years old) who are heavy cigarette smokers.
What are the clinical manifestations of Buerger’s disease?
Clinical manifestations include:
Severe circulatory insufficiency in distal extremities
Raynaud’s phenomenon
Potential need for amputation if there is gangrene.
What is the primary treatment for Buerger’s disease?
The primary treatment for Buerger’s disease is smoking cessation.
What is vasculitis?
Vasculitis is a group of disorders characterized by inflammation that destroys blood vessels, affecting both arteries and veins, often due to autoimmune disorders that damage the endothelium.
What are general symptoms of vasculitis?
General symptoms include:
Fever
Weight loss
Fatigue
What are the mechanisms of systemic vasculitis?
Immune complex deposition: e.g., Polyarteritis nodosa (PAN), Henoch-Schönlein purpura
Autoantibodies (ANCA): e.g., Wegener’s granulomatosis, Microscopic polyangiitis, Churg-Strauss syndrome
T-cell mediated (CD4+ T cells): e.g., Takayasu arteritis, Giant cell arteritis
What are the types of great vessel vasculitis?
The main types of great vessel vasculitis include:
Giant cell arteritis (temporal arteritis)
Takayasu arteritis
What treatment options are available for vasculitis?
Treatment options include:
Corticosteroids (e.g., prednisone)
Aspirin
Methotrexate
Cyclophosphamide
IL-6 inhibitors (e.g., tocilizumab)
Revascularization when needed
What is the role of corticosteroids in treating vasculitis?
Corticosteroids are used to reduce inflammation and suppress the immune response in various forms of vasculitis.
When is revascularization needed in the treatment of vasculitis?
Revascularization may be necessary in cases where there is significant vascular obstruction leading to ischemia or gangrene, especially in conditions like Buerger’s disease or severe cases of Takayasu arteritis.
What are the two major types of large vessel vasculitis?
The two major types of large vessel vasculitis are:
Giant Cell Arteritis (Temporal Arteritis)
Takayasu Arteritis
Who is most commonly affected by Giant Cell Arteritis?
Giant Cell Arteritis typically affects older individuals, particularly those over the age of 50.
Which arteries are most frequently involved in Giant Cell Arteritis?
The most frequently affected arteries are:
External carotid artery
Ophthalmic artery
Temporal artery
What is the suspected underlying cause of Giant Cell Arteritis?
The underlying cause is unknown, but it may be related to helper T-cell activation.
What are the key symptoms of Giant Cell Arteritis?
Key symptoms include:
Headache
Jaw claudication (pain in jaw when chewing)
Scalp tenderness
Visual abnormalities
Fever
How is Giant Cell Arteritis diagnosed?
Diagnosis involves:
Elevated CRP (C-reactive protein) and ESR (erythrocyte sedimentation rate)
Biopsy: Removing a small section of the affected artery to examine for giant cells infiltrating the tissue, specifically in the internal elastic lamina.
A long section is needed due to the segmental nature of the disease.
What is the main treatment for Giant Cell Arteritis?
The main treatment includes:
High-dose corticosteroids (e.g., prednisone)
Aspirin (100 mg)
Methotrexate
Anti-TNF therapy (e.g., infliximab)
Who is most commonly affected by Takayasu Arteritis?
Takayasu Arteritis primarily affects younger individuals, particularly women under 50, and is more common in Asian populations.
What is the pathophysiology of Takayasu Arteritis?
Takayasu Arteritis is a form of large vessel granulomatous vasculitis characterized by massive intimal fibrosis and vascular narrowing, mainly affecting the aorta and its branches, as well as the pulmonary arteries.
What are the key symptoms of Takayasu Arteritis?
Key symptoms include:
“Pulseless disease” (weaker pulses in the upper extremities)
Fever
Night sweats
Skin nodules
Ocular disturbances
How is Takayasu Arteritis diagnosed?
Diagnosis involves:
Elevated CRP and ESR
Magnetic Resonance Angiography (MRA) to visualize vascular lesions
What is the treatment for Takayasu Arteritis?
Treatment includes:
Corticosteroids (e.g., prednisone)
Methotrexate
Azathioprine
Tocilizumab (IL-6 inhibitor)
- What are the primary treatment goals for atrial fibrillation?
The primary treatment goals for atrial fibrillation are:
Restoration and maintenance of sinus rhythm (if possible).
Ventricular rate control.
Prevention of blood clots and thromboembolism.
What is the purpose of cardioversion in atrial fibrillation treatment?
Cardioversion aims to reset the heart’s normal rhythm, stopping the irregular electrical activity.
What are the two types of cardioversion used in atrial fibrillation?
Electrical cardioversion: An electrical shock (100-200J) is delivered to the heart to restore normal rhythm.
Chemical cardioversion: Medications such as amiodarone and procainamide are used to restore normal rhythm.
What anti-arrhythmic medications are used after electrical cardioversion?
After electrical cardioversion, anti-arrhythmic medications include:
Amiodarone
Sotalol
What medications are used for heart rate control in atrial fibrillation?
Beta-blockers (e.g., metoprolol, esmolol) to slow the heart rate.
Calcium channel blockers (e.g., verapamil, diltiazem) to control heart rate.
Describe catheter ablation for atrial fibrillation treatment.
Catheter ablation involves inserting long, thin tubes (catheters) through a vein or artery into the heart to destroy areas of heart tissue causing irregular heartbeats using radiofrequency energy or cryotherapy.
When is catheter ablation indicated for atrial fibrillation patients?
Catheter ablation is indicated after one failed anti-arrhythmic drug therapy or without previous drug therapy based on patient preference.
What is the success rate of catheter ablation in patients with paroxysmal/persistent atrial fibrillation?
In patients with paroxysmal/persistent atrial fibrillation, catheter ablation provides long-term symptom control in 70% to 80% of cases, especially with a structurally normal heart and normal-sized left atrium.
What is the Maze procedure in atrial fibrillation treatment?
The Maze procedure is an invasive surgical treatment that creates electrical blocks or barriers in the atria, forcing abnormal electrical impulses to travel uniformly to the ventricles, restoring normal rhythm.
Where do most thromboembolic events originate in atrial fibrillation?
The vast majority of thromboembolic events in atrial fibrillation originate from the left atrial appendage.
What is the most serious consequence of thromboembolism in atrial fibrillation?
The most serious consequence of thromboembolism in atrial fibrillation is an ischemic stroke.
How is thromboembolic risk assessed in patients with atrial fibrillation?
Thromboembolic risk is assessed using the CHA2DS2-VASc score:
A score of 2 or more indicates the need for long-term oral anticoagulant treatment.
A score of 0 generally requires no therapy.
What types of anticoagulants are used in the management of atrial fibrillation?
Vitamin K antagonists (e.g., warfarin)
NOACs (Non-Vitamin K Oral Anticoagulants), such as:
Dabigatran
Rivaroxaban
Apixaban
Edoxaban
What is the mechanism of action of Warfarin?
Warfarin is a vitamin K antagonist that inhibits the synthesis of vitamin K-dependent clotting factors (II, VII, IX, and X) in the liver.
What are the key requirements for patients on Warfarin?
Patients on Warfarin require regular blood tests (INR monitoring) to ensure therapeutic levels and prevent bleeding complications.
Name two Factor Xa inhibitors used as anticoagulants.
Two Factor Xa inhibitors are Rivaroxaban and Apixaban.
How do Factor Xa inhibitors differ from Warfarin?
Factor Xa inhibitors are shorter-acting, usually do not require regular blood tests or monitoring, and have a more predictable pharmacokinetic profile than Warfarin.
What is the normal function of the pericardium?
The pericardium is a double-layered sac that surrounds the heart, consisting of a serous visceral layer and a fibrous parietal layer, separated by a small amount of fluid that acts as a lubricant.
Define pericarditis.
Pericarditis is the inflammation of the pericardium, the fibrous sac surrounding the heart.
How is pericarditis clinically classified based on duration?
Acute pericarditis: < 6 weeks
Fibrinous
Effusive
Subacute pericarditis: 6 weeks to 6 months
Effusive-constrictive
Constrictive
Chronic pericarditis: > 6 months
Constrictive
Effusive
Adhesive (non-constricted)
How is pericarditis classified etiologically?
Infectious pericarditis:
Viral (e.g., coxsackievirus, echovirus, HIV)
Pyogenic (e.g., pneumococcus, streptococcus)
TB
Fungal (e.g., histoplasmosis)
Non-infectious pericarditis:
Acute myocardial infarction
Uremia
Neoplasia
Aortic dissection
Autoimmune diseases (e.g., SLE, rheumatoid arthritis)
Drug-induced
Post-cardiac injury
What are common clinical features of pericarditis?
Severe, pleuritic chest pain (improves when sitting and leaning forward)
Pericardial friction rub on auscultation
Pericardial effusion visible on chest x-ray
What diagnostic methods are used for pericarditis?
Echocardiography (for suspected effusion)
CT/MRI
ECG: shows diffuse ST elevation (saddle-shaped) and PR depression
What ECG changes are associated with pericarditis?
Diffuse ST elevation (saddle-shaped)
PR segment depression
PR elevation in lead aVR
ST segment normalizes after about 1 week
T-wave inversion (not in all patients)
What is the first-line treatment for pericarditis?
The first-line treatment is bed rest and anti-inflammatory treatment with aspirin (with omeprazole for gastric protection).
What are the second and third lines of treatment for pericarditis?
Second line: NSAIDs
Third line: Colchicine (for inflammation and pain) and glucocorticoids (for 2-4 days).
Why should anticoagulants be avoided in pericarditis?
Anticoagulants should be avoided as they could cause bleeding into the pericardial cavity, leading to cardiac tamponade.
What are common complications of pericarditis?
Common complications include:
Cardiac tamponade
Pericardial effusion
What is constrictive pericarditis?
Constrictive pericarditis is a medical condition characterized by a thickened, fibrotic pericardium that forms a non-compliant shell around the heart, preventing it from expanding during diastolic filling.
How does constrictive pericarditis affect the heart’s filling?
A rigid, fibrotic pericardium restricts diastolic filling. When intracardiac volume reaches the limit set by the noncompliant pericardium, ventricular filling is abruptly halted, unlike cardiac tamponade where filling is impeded throughout diastole.
What are common causes of constrictive pericarditis?
Thickened, rigid pericardium due to acute pericarditis.
Uremia
Radiation therapy
Tuberculosis
Chronic pericardial effusion
Tumor invasion
Connective tissue disorders
Histoplasmosis
Prior surgery involving the pericardium
What symptoms indicate fluid overload in constrictive pericarditis?
Symptoms of fluid overload include:
Jugular vein distention (most prominent finding)
Kussmaul sign: paradoxical rise in JVP on inspiration
Hepatomegaly
Peripheral edema and ascites
What symptoms indicate reduced cardiac output in constrictive pericarditis?
Symptoms of reduced cardiac output include:
Fatigue and dyspnea on exertion
Pericardial knock: a high-pitched early diastolic sound
Tachycardia
Pulsus paradoxus: decreased blood pressure amplitude during deep inspiration
What ECG changes are seen in constrictive pericarditis?
ECG may show nonspecific changes such as:
Low QRS voltages
Generalized T-wave flattening or inversion
Left atrial abnormalities
Atrial fibrillation may be seen in advanced disease (in fewer than half of patients).
What does an echocardiogram reveal in constrictive pericarditis?
Echocardiogram may show:
Increased pericardial thickness in about half of patients
Sharp halt in ventricular diastolic filling
Atrial enlargement
Evidence of septal bounce and reduced mitral inflow velocities with inspiration.
What findings can CT scan and MRI provide in constrictive pericarditis?
CT and MRI can show pericardial thickening and calcifications, aiding significantly in diagnosis.