W4 Cardiac Ischemia

• Mitral stenosis is characterized by the stiffening of the mitral valve
• Atrial dilation is caused by mitral stenosis, leading to atrial stretching and hypertrophy
• Pulmonary hypertension results from mitral valve stenosis, causing high blood pressure in the pulmonary circuit
• Right Ventricle Hypertrophy occurs due to mitral valve stenosis, backing up blood through the pulmonary circuit and creating afterload for the right ventricle
• Mitral regurgitation involves blood flowing back through the mitral valve to the atria, leading to a reduction in EF, preload, afterload, and oxygen delivery
• Mitral valve prolapse, more common in females, involves the mitral valve folding the wrong way and can be asymptomatic for a long time
• Aortic stenosis is characterized by the aortic valve becoming hard to open, with the highest incidence in the 70-90 age range
• Aortic regurgitation is caused by an incompetent aortic valve, leading to increased end-diastolic volume, hypertrophy, and sometimes bounding peripheral pulses
• Nitric Oxide, produced by coronary arteries, is a potent vasodilator that increases with hypoxemia
• Ischemia is cell injury caused by the failure of the body to meet the cell's oxygen demand, while infarction is cell death caused by untreated ischemia
• Infarction produces pathological q waves on an ECG, hypoxic injury produces ST elevation
• Myocardial stunning occurs when cardiac cells are not functioning properly despite adequate perfusion
• Hibernating myocardium is a metabolic adaptation where cardiac cells do minimal work to match a drop in supply
• Myocardial remodeling involves cardiac cells undergoing hypertrophy due to factors like aldosterone and cytokines
• Coronary artery disease is characterized by the narrowing of coronary arteries due to plaque buildup
• Angina pectoris is chest pain related to ischemia without infarction, with stable angina related to stenotic atherosclerosis and unstable angina caused by clot or plaque blocking coronary vessels
• Prinzmetal Angina is an unpredictable attack due to coronary vessel spasm, often occurring after hours of sleep and treated by calcium channel blockers
• Hypertrophic obstructive cardiomyopathy is an abnormal thickening of the myocardium, leading to sudden cardiac arrest
• Class 1 antiarrhythmics block Na channels to interfere with phase 0 of the cardiac action potential
• Class 2 antiarrhythmics are beta blockers that interfere with phase 2 of the cardiac action potential
• Class 3 antiarrhythmics are K channel antagonists that extend phase 3 of the cardiac action potential
• Class 4 antiarrhythmics are calcium channel blockers that interfere with phase 2 of the cardiac action potential
• Norepinephrine speeds up phase 4 of the cardiac action potential
• The QT interval represents ventricle depolarization and repolarization on an ECG
• The J point marks the end of the QRS complex on an ECG
• The ST segment represents the time from the J point to the start of the T wave on an ECG
• The RR interval is the time from one R wave to the next, used to calculate heart rate
• The U wave may represent repolarization of Purkinje fibers and is seen in certain conditions like hyperkalemia
• NSTEMI is a non-full thickness myocardial infarction treated by various medications, while STEMI is a full-thickness MI usually treated by PCI or thrombolysis
• Pathological Q waves on an ECG indicate a past transmural MI that is permanently recorded