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Bundle branch block
Pulseless electrical activity
Atrioventricular nodal reentrant tachycardia (AVNRT)
Premature atrial contraction
Long QT syndrome and Torsade de pointes
Premature ventricular contraction
Rheumatic heart disease
Atrial septal defect
Coarctation of the aorta
Patent ductus arteriosus
Ventricular septal defect
Hypoplastic left heart syndrome
Tetralogy of Fallot
Total anomalous pulmonary venous return
Transposition of the great vessels
Pericarditis and pericardial effusion
Aortic valve disease
Mitral valve disease
Pulmonary valve disease
Tricuspid valve disease
Coronary steal syndrome
Polycystic kidney disease
Renal artery stenosis
Peripheral artery disease
Subclavian steal syndrome
Superior mesenteric artery syndrome
Human herpesvirus 8 (Kaposi sarcoma)
Chronic venous insufficiency
Deep vein thrombosis
Acyanotic congenital heart defects: Pathology review
Aortic dissections and aneurysms: Pathology review
Atherosclerosis and arteriosclerosis: Pathology review
Cardiac and vascular tumors: Pathology review
Cardiomyopathies: Pathology review
Coronary artery disease: Pathology review
Cyanotic congenital heart defects: Pathology review
Dyslipidemias: Pathology review
Endocarditis: Pathology review
Heart blocks: Pathology review
Heart failure: Pathology review
Hypertension: Pathology review
Pericardial disease: Pathology review
Peripheral artery disease: Pathology review
Shock: Pathology review
Supraventricular arrhythmias: Pathology review
Valvular heart disease: Pathology review
Vasculitis: Pathology review
Ventricular arrhythmias: Pathology review
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Atrioventricular Block Types
Mikey is a 22 year old male college student from Vermont who was sent to the emergency department after passing out.
His vital signs show a heart rate of 40 beats per minute and a blood pressure of 90/50. On examination, there is an erythematous circular rash with central clearing.
His friends mention they recently went on a hiking trip. His ECG is as follows.
Natasha is a 60 year old female with chronic hypertension, diabetes, and peripheral vascular disease who comes to the emergency room complaining of sudden-onset, squeezing retrosternal chest pain accompanied by shortness of breath and sweating.
Her ECG is as follows. On laboratory evaluation, her troponin levels are significantly elevated.
Alright, so the normal electrical activity of the heart starts in the sinoatrial or SA node located near the opening of the superior vena cava into the right atrium.
Electrical activity is then conducted through the atrium to the atrioventricular, or AV node, after which it goes through the Bundle of His, then the right and left branches of the Bundle, and finally through the Purkinje fibers which deliver the current to the right and left ventricles.
Now, normally there is delay in conduction at the AV node and the Bundle of His, which gives some time for ventricular filling before the ventricle contracts.
A “heart block”, or AV block, occurs when conduction is delayed for too long at the AV node or the bundle of His. Also, electrical activity may be blocked at the level of the bundle branches, which are called bundle branch blocks.
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