Patho Exam 2 - Chapter 24 - Coronary Disorders

Why is coronary circulation important?

The heart is the first organ supplied w. blood and O2 so how its doing affects the whole body

Coronary Artery Disease(CAD)

Reduced supply of oxygen and nutrients

Coronary Heart Disease(CHD)

Problems w. circulation and narrowing of blood vessels in brain and heart

REMEMBER - PVD is everything BESIDES brain and heart

CHD Ex.

• Angina pectoris

• Acute coronary syndrome

• Silent myocardial ischemia

• Myocardial infarction

Cardiovascular Disease(CVD)

Pathologic process causing heart disease and coronary and systemic circulation

CVD ex.

• Stroke

• Transient ischemic attack(TIA)

• Claudication

• Limb ischemia

Ischemia

Deficiency of blood flow in tissue

Myocardial infarction

Necrosis in myocardium because of obstructed blood flow

When is there the most blood flow to the myocardium?

During ventricular diastole

Coronary collateral circulation

Small blood vessels developed during CAD to be an alternative route for blood to get to the myocardium

How can CAD affect Endothelial cells(EC)?

AC → EC damaged → Opening in blood vessels → Clot goes to fix it → Thrombus

How can CAD affect Smooth Muscle Cells(SMC)?

CAD → Cells become hyperactive in tunica media → Artery suddenly narrows → Vasospasm →Decreased blood flow → Ischemia

How can CAD affect Blood Vessel Wall?

It can damage the blood vessel wall → Plaque gets in → PAD, CAD, Aneurysms, Atherosclerosis

CAD diagnosis

Treadmill test - Pt. walks on treadmill connected to ECG and BP cough and look to see any presence of dysrhythmia

Diagnosis CAD

• Blood tests

• Nuclear stress test

• Coronary angiography/arteriography

CAD Treatments

• Lifestyle changes

• Hypertension management

• Lipid-lowering therapy(Statins)

• Anxiety management

For how long is coronary occlusion reversible?

20 minutes

Cell features during myocardial ischemia and infarction

• Atherosclerosis

• Coronary blood flow disruption

• Ischemic myocardial fibers cant contract

• Cardiac conduction system fucked - cant send electrical signals

• Ischemic cascade

Ischemic Cascade Steps

No O2 so →

1. Messed up electrolyte balance

2. Anaerobic metabolism - Na/Ca accumulate → Edema

3. Systolic/dysfunction

4. ECG weird

Subendocardial Injury

Damage to inner layer of heart - myocardium

Transmural Injury

Damages ENTIRE tissue through and through innermost to outermost part

Like this class is doing to my mental state! :)

How does Subendocardial Injury affect the ST wave?

ST wave depression

How does Transmural Injury affect the ST wave?

ST wave elevation

Stable Angina

Chronic form of ischemic heart disease(IHD),

• Increased myocardial O2 demand

• Reduced blood flow                                                                                                 w. stress/exertion

Stable Angina Symptoms

• Pain

• SOB

• Nausea 

Stable Angina Treatment

• Short-acting nitroglycerin - vasodilator → Improves blood flow and reduces work for heart

• Antiplatelet meds

• Antihypertensives

• Rest

Silent Ischemia

One step above stable angina, same cause - but NO SYMPTOMS

Silent Ischemia Clinical Manifestations

ST segment changes - depression

Silent Ischemia Clinical Manifestations

• Ambulatory ECG

• SPECT

Silent Ischemia Treatment

Same as symptomatic ischemia(stable angina)

Coronary Microvascular Disease

Idiopathic damage to walls of small coronary arteries - anginas with out presence of ischemia

Coronary Microvascular Disease Diagnosis

• Transthoracic Doppler echocardiography

• SPECT

• CMR myocardial perfusion imaging

Acute Coronary Syndromes(ACS)

Acute CAD

Types of ACS

• Non-ST-segment Elevation Acute Coronary Syndrome(NSTEMI) - unstable angina

• ST-Segment elevation myocardial infarctions(STEM)

ACS Risk Factors

• CAD

• Other triggers being explored

Shared pathophysiology between CAD and ACS

• ACS can turn into CAD

• Atherosclerotic plaque

Thrombogenesis  and blood flow obstruction

What is the difference between stable and unstable angina?

Stable occurs mostly with just exertion, but unstable can occur at rest too - unstable means theres a lack of oxygen more of the time

Most precise def. of heart attack

ST-Segment Elevation Myocardial Infarction

ACS Mechanical Complications

• Sudden cardiac death

• Ventricular aneurysm and rupture

• Heart failure

• Mitral regurgitation

ACS Inflammatory Complications

• Pericarditis

• Dressler Syndrome

Dysrhythmia(Cardiac Arrest)

Electrical Tissue - Myocardium doesn’t get signal to contract → Abrupt loss of cardiac function

Dysrhythmia Causes

• Acute MI - plaque ruptures 

• Thrombosis fully blocks coronary artery

• ANS dysfunction - synotrial nodes

Dysrhythmia Clinical Manifestations

Same as CAD bu FASTER

Dysrhythmia Diagnosis

• ECG

• Continual heart monitoring

• Exercise and stress testing

• LONG TERM ECG

Dysrhythmia Treatment

• Antiarrythmias

• Anticoagulants

• Pacemakers

• Integrated approach

Myocardial Rupture

• Ischemia, MI → Free walls of right ventricle, ventricular septum, left ventricle of papillary muscle 

• Trauma

• Abscesses

Myocardial Complications

• Acute mitral regurgitation

• Cardiac Tamponade

Ventricular Aneurysm

MI → Defect in left or right ventricle wall - bulges outward

Ventricular Aneurysm Diagnosis

Systolic murmur, ECG characterized by ST elevation

Ventricular Aneurysm Treatment

• Aneurysmectomy

• Management of complications

Ventricular Septal Rupture

Complete coronary artery occlusion/little collateral circulation → Abnormal opening left and right ventricle

Ventricular Septal Rupture Diagnosis

• Echocardiography w. Doppler

• Cardiac catheterization

Ventricular Septal Rupture Treatment

Surgery → Open chest and remove aneurysm

Pericarditis

Swelling, Inflammation, or Infection in pericardium and membrane as a result of injury

Dressler Syndrome

Vessels leak into pericardial cavity

Pericarditis Clinical Manifestations

• Pleutric chest pain

• Pain worse swallowing, coughing, swallowing, etc.

Pericarditis Diagnosis

• ST segment elevation

• Pericardial effusion on echo or CT

Pericarditis Treatment

• Aspirin

• Hospitalization