Kin 122 1st Edition Lecture 17Current LectureCoronary artery disease• Most common form of cardiovascular disease• Occurs when the coronary arteries become hardened and narrowed due to plaque build-upAtherosclerosisAtherosclerosis• Process in which deposits of fatty substances, cholesterol, cellular waste products, calcium and other substances build up in the inner lining of an artery Atherosclerosis – consequences• Over time = reduced blood flow & supply• May or may not be symptomatic• Plaques can rupture and cause blood clots • Leads to:Angina Heart attack StrokeAngina• Pain in chest (typically)• Caused by lack of oxygen to the heart • Due to blockage of coronary arteries• Typically brought on by stress or physical activity• May experience angina before a heart attack• Not all people who experience angina go on to have a heart attack• Not all heart attacks are preceded by an “angina attack”• Treatment: rest or nitroglycerin Heart attack• Myocardial infarction (MI)• Coronary artery blockageThese notes represent a detailed interpretation of the professor’s lecture. GradeBuddy is best used as a supplement to your own notes, not as a substitute.• Blood flow to a portion of the heart is blocked in one or more of the coronary arteries • Heart tissues below blockage do not receive blood & oxygen• Can suffer irreversible damage if blood supply is not quickly restored• Damage can be minor, major, or fatal Atherosclerosis treatment• Opening up the blocked arteryAngioplastyStent• Risk of restenosis Angioplasty – 30% at 6 monthsStent – 10-12% at 6 months• Going around the blocked arteryCoronary artery bypass graft (CAGB)Vessels from leg or arm grafted to bypass blocked coronary artery/arteries Peripheral artery disease• Atherosclerosis of peripheral arteries• Lack of blood supply in the extremities• Sign of advanced, widespread vascular disease• Causes pain, weakness, numbness• Amputation can be necessary• High risk for morbidity/mortality Congestive heart failure• Heart has been damaged to the degree that it can no longer properly function• “Congestive” refers to fluid build-up• Blood pools in heart and/or lungs because heart can’t pump out to the body efficiently • About half of those with CHF die within 5 years of their diagnosisArrhythmias• Abnormal heartbeatProblem with heart’s electrical impulsesHeart rate• Electrical conduction• Starts from the SA nodePacemaker Controls firing rateNormal HR =60-100 beats/minContraction of the heart• Measured as ECG/EKG Electrodes placed on specific sites of the body capture activity of the heartProduces a rhythm that reflects contraction/ relaxation processArrhythmias• Abnormal heartbeatSA node fires faster or slower than normalOther areas of the heart act as “pacemakers”• Some arrhythmias reflect underlying disease, others are harmless• Can result in incomplete filing of the heart chambers• Some examples:Sinus bradycardia – SA node fires <60 bpm• Can occur with exercise trainingSinus tachycardia – SA node fires > 100 bpmStroke• “Brain attack” caused by lack of blood flow to the brainBlockage of cerebral arteriesBrain cells die within minutesTypes of stroke• 2 Types of Stroke: Ischemic Stroke Obstruction of blood vessel 80-85% of all stroke casesHemorrhagic StrokeWeakened vessel that ruptures and bleeds into the surrounding brain 15-20% of all stroke casesTIA• Transient ischemic attack“mini-stroke” or “warning-stroke”• Same signs and symptoms as stroke• Blockage & symptoms are temporaryUsually less than 5 minutes• Typically no permanent damage• High risk for stroke after TIA 30% within 1 year go on to have a