Cardiovascular Pathology Module 1

The heart is covered by a tough membrane called the ______

pericardium

What is the purpose of the pericardium?

Separate the heart from the other structures in the mediastinum

The heart is centrally located in the mediastinum, which allows the hart to…

pump oxygen-rich blood to the body and send deoxygenated blood to the lungs for gas exchange

How is the heart functionally divided?

Into the right heart (right atrium and right ventricle) and left heart (left atrium and left ventricle)

Which vessels bring deoxygenated blood to the heart?

The superior and inferior vena cava

Where does the superior and inferior vena cava drain into?

Right atrium

What is the pathway of blood from the right ventricle to the lungs?

Right ventricle > pulmonary artery > lungs

Which vessels return oxygenated blood from the lungs to the heart?

The four pulmonary veins

Where do the four pulmonary veins drain into?

Left atrium

From which chamber is blood pumped into the systemic circulation?

The left ventricle via the aorta

What is the function of the left heart?

To pump oxygenated blood to the systemic circulation

What arteries supply blood to the heart muscle itself?

The right and left coronary arteries and their branches

How does venous blood drain from the myocardium?

Via cardiac veins (middle and small cardiac veins, left posterior ventricular vein) into the coronary sinus

Why is the heart’s mediastinal position important?

Allows efficient pumping of blood to the lungs for gas exchange and to the body for systemic circulation

What is Atherosclerosis?

Condition in which plaque builds up in the arterial walls, hardening and narrowing the arteries

What lifestyle factors help prevent Atherosclerosis?

Smoking cessation
Maintaining normal blood pressure
Avoiding high-fat and high-sugar diets

Who is at increased risk for developing Atherosclerosis?

Males
Postmenopausal women
Individuals with family history of cardiovascular disease

What physical exam findings may suggest Atherosclerosis?

Diminished distal pulses and bruits (whooshing sounds heard with a stethoscope)

What is Angioplasty?

A procedure using a balloon to open a narrowed artery, often followed by stent placement to keep it open

What is Arteriosclerosis?

A general term for thickening, hardening and loss of elasticity of arterial walls

What conditions are commonly associated with Arteriosclerosis?

Hypertension and diabetes mellitus

What is Arteriolosclerosis?

Hardening and stiffening of small arteries, commonly affecting renal (kidney) blood flow

What is Angina Pectoris?

Chest pain and discomfort caused by reduced coronary blood flow, leading to myocardial ischemia

How is Angina pain commonly described?

A sensation of pressure, tightness or squeezing in the chest

What defines Stable (Chronic) Angina?

Predictable chest pain with exercise or stress due to the heart muscle not getting enough oxygen (usually occurring when there is >70% coronary artery stenosis)

Why does Stable Angina occur during activity but not rest?

Blood flow is sufficient at rest but insufficient to meet increased myocardial oxygen demand during exertion

What is the most common cause of Stable Angina?

Atherosclerosis

What is Unstable Angina?

Chest pain or discomfort that occurs at rest or with minimal exertion and does not reliably resolve

What causes Unstable Angina?

Rupture of an atherosclerotic plaque with thrombus formation, further reducing coronary blood flow

Why is Unstable Angina considered dangerous?

It indicates acute myocardial ischemia and has a high risk of progressing to myocardial infarction

What is a Myocardial Infarction?

A heart attack

How does a Myocardial Infarction occur?

Blood flow to the heart is suddenly blocked, starving heart cells of oxygen and causing tissue death

What is the most common cause of Myocardial Infarctions?

Atherosclerosis of coronary arteries

What are some signs/symptoms of Myocardial Infarctions?

Severe chest pain that may radiate to the left arm or jaw
Diaphoresis
Nausea
Fatigue
Dyspnea

Which coronary artery supplies the anterior wall and septum of the left ventricle?

Left Anterior Descending (LAD)

Which coronary artery supplies the posterior wall, septum and papillary muscles of the left ventricle?

Right Coronary Artery (RCA)

Which coronary artery supplies the lateral wall of the left ventricle?

Left Circumflex Artery

Why is the left ventricle most commonly affected in myocardial infarctions?

Because the LAD, RCA, and Left Circumflex Artery primarily supply the Left Ventricular Tissue

Where do the coronary arteries reside in the heart?

In the epicardium (outer layer of the heart)

What are the two main zones of perfusion affected during an MI?

Endocardium (inner lining) and myocardium (muscle layer)

What happens in the first minute after coronary artery blockage?

Ischemia occurs, contractility is reduced, but damage may be reversible

When does irreversible myocardial damage begin after artery blockage?

20-40 minutes after ischemia onset; cells begin to die, forming the infarcted zone

Why is rapid treatment crucial in MI?

Because once myocardial cells die, they cannot regenerate, so restoring blood flow quickly can save heart muscle

What does NSTEMI stand for and how is it seen on ECG?

Non-ST Elevation MI; caused by partial-thickness infarction

What does STEMI stand for and how is it seen on ECG?

ST Elevation MI; involves full thickness infarction of the myocardial wall

Which cardiac enzymes are key markers to MI?

Troponin I, Troponin T, CK-MB

How long do Troponin I and T levels rise, peak and stay elevated for after an MI?

Rise: 2-4 hours
Peak: 48 hours
Remain elevated: up to 10 days

When do CK-MB levels risk, peak and return to normal after an MI?

Rise: 2-4 hours
Peak: 24 hours
Return to Normal: 48 hours

Why is CK-MB useful in diagnosing reinfarction?

Because CK-MB returns to normal faster than Troponin, so a second MI can be detected even while Troponin is still elevated

What percentage of MI patients may experience a second infarction before Troponin levels normalize?

About 10%

What is Atrial Fibrillation?

Rapid, irregular heart rate

How does normal atrial contraction occur?

SA node > rapid conduction through atria > coordinated contraction . signal reaches ventricles > blood pumped into aorta

What happens to atrial contraction during A-fib?

Multiple uncoordinated contractions > atria quiver > inefficient blood emptying

Major cardiovascular risk factors for A-fib?

Hypertension
Coronary Artery Disease
Valvular Heart Disease
Atrial Stretch
Inflammation

Major non-cardiovascular risk factors for A-fib?

Obesity
Diabetes
Excessive alcohol use
Genetic predisposition

What is Paroxysmal A-fib?

Irregular heart beat that starts and stops suddenly; self terminating within 7 days

What is Persistent A-fib?

Irregular, rapid heartbeat lasting over 7 days that does not stop on its own

What is Long-Standing Persistent A-fib?

Continuous irregular heart rhythm for over a year

What is Permanent A-Fib?

Irregular heart rhythm that can’t be restored to normal with treatment

Why is A-Fib a risk factor for stroke?

Quivering atria > blood pooling > thrombus formation > potential embolization to brain > ischemic stroke

What is the most common symptom of A-Fib? Why?

Fatigue, due to inefficient blood delivery from irregular contractions

Name other common symptoms of A-Fib

Dizziness
Shortness of Breath
Weakness
Palpitations/thumping in the chest

What are the main medication strategies for A-Fib?

Rate control (beta-blockers, calcium channel blockers)
Anticoagulation to prevent stroke

How can an implantable pacemaker help patients with A-Fib?

Stimulates the atrium, reducing the frequency of A-Fib episodes

What is radiofrequency catheter ablation?

Destroying atrial tissue causing abnormal electrical signals to stop A-Fib propogation

What is the Maze procedure?

Creating a maze of new conduction pathways in the atria to restore organized electrical activity

Why is an AV node ablation sometimes combined with a pacemaker?

Disconnecting the AV node stops atrial signals from reaching the ventricles, so a pacemaker ensures ventricular contraction

What is a normal blood pressure reading?

Systolic <180
Diastolic < 80

What is an elevated blood pressure reading?

Systolic: 120-129
Diastolic: <80

What is Stage 1 High Blood Pressure reading?

Systolic: 130-139
Diastolic: 80-89

What is Stage 2 High Blood Pressure reading?

Systolic: 140+
Diastolic: 90+

What is a Hypertensive Crisis reading?

Systolic: 180+
Diastolic: 120+

What is Hypertension?

Chronic high blood pressure that can damage blood vessels and organs over time

What are the two main types of Hypertension?

Primary (essential) and secondary

What is Primary Hypertension?

Hypertension without a clearly identifiable cause

What percentage of Hypertension is Primary?

90%

Risk factors for primary hypertension?

Age
Obesity
High salt/fat diet
Sedentary lifestyle

What is Secondary Hypertension?

There is a specific, identifiable cause to the hypertension

What are some causes of Secondary Hypertension?

Renal artery stenosis
Atherosclerosis
Vasculitis
Aortic dissection

How does reduced kidney perfusion cause secondary hypertension?

Not enough blood flows to the kidneys, so the kidney secretes the hormone renin, which helps the kidneys retain more water. This increase in sodium/water retention causes blood pressure to rise.

What is a Hypertensive Urgency?

High BP without end-organ damage

What is Hypertensive Emergency?

High BP with evidence of end-organ damage

What is Left-Sided Heart Failure?

Inability of the left ventricle to pump oxygenated blood to the body, causing pulmonary congestion

What is a common cause of left-sided heart failure?

Coronary artery disease, leading to myocardial damage, reducing contractility

What is right-sided heart failure?

Inability of the right ventricle to pump deoxygenated blood to the lungs, causing systemic venous congestion

What is a common cause of right-sided heart failure?

Left-sided heart failure, which increases pressure in the lungs, causing right ventricular strain

What is Cor Pulmonale?

Chronic lung disease leading to right-sided hypertrophy and failure

What are some clinical signs of right-sided heart failure or cor pulmonale?

Jugular venous distention
Peripheral edema
Systemic venous congestion

How is Cor Pulmonale diagnosed?

EKG
Right heart catheterization
Spirometry to evaluate lung function

How is heart failure treated?

Treat underlying cause
Provide supplemental oxygen if needed
Manage fluid overload and cardiac function

What are some signs/symptoms of Left Sided Heart Failure?

Paroxysmal Nocturnal Dyspnea
Pulmonary Congestion
Confusion
Fatigue
Restlessness
Cyanosis

What are some signs/symptoms of Right Sided Heart Failure?

Fatigue
Increased Peripheral Venous Pressure
Enlarged Liver/Spleen
Weight Gain
Distended Jugular Veins

What is the NYHA Class 1 of Heart Failure?

No symptoms with normal physical activity.
Normal functional status

What is NYHA Class 2 of Heart Failure?

Mild symptoms with normal physical activity.
Comfortable at rest.
Slight limitation of functional status

What is NYHA Class 3 of Heart Failure?

Moderate symptoms with less than normal physical activity.
Comfortable only at rest.
Marked limitation of functional status

What is NYHA Class 4 of Heart Failure?

Severe symptoms with features of heart failure with minimal physical activity and even at rest.
Severe limitation of functional status

What is cardiomyopathy?

Disease of the myocardium that affects heart structure and function

What is Primary Cardiomyopathy?

Develops independently

What is Secondary Cardiomyopathy?

Compensates for an underlying disease

What is Dilated Cardiomyopathy?

A disease where the heart's main pumping chamber (left ventricle) becomes dilated (enlarged), stretched, and weakened, making it unable to pump enough oxygen-rich blood to the body