cardio test cram I

Valves

Control one-way blood flow through the heart, preventing backflow. The main valves are the tricuspid, pulmonary, mitral, and aortic valves. They ensure that blood moves efficiently from one chamber to the next and into circulation.

Blood flow

Blood flows through the heart in a specific pattern: from the body (via vena cavae) → right atrium → tricuspid valve → right ventricle → pulmonary valve → lungs → pulmonary veins → left atrium → mitral valve → left ventricle → aortic valve → aorta → body.

Conduction system (who what where)

The conduction system controls the heart’s electrical impulses: SA node (pacemaker) → AV node → Bundle of His → right and left bundle branches → Purkinje fibers. It coordinates contraction for efficient pumping.

Layers of the heart from the outside in

The heart has three layers: epicardium (outer protective layer), myocardium (muscular middle layer that contracts), and endocardium (inner smooth lining that prevents clotting).

Capillary blood flow (which pipes do what?)

Arteries carry oxygenated blood away from the heart, veins carry deoxygenated blood toward the heart, and capillaries allow for gas and nutrient exchange between blood and tissues.

External and Internal respirations

External respiration occurs in the lungs (gas exchange between alveoli and blood). Internal respiration occurs in tissues (exchange between blood and body cells).

What pulses to palpate

Common EMT-level pulses: carotid (for unresponsive), radial (for responsive), brachial (infants), femoral, dorsalis pedis, and posterior tibial for perfusion checks.

Preload and Afterload

Preload is the amount of blood returning to the heart before contraction (stretch of ventricles). Afterload is the resistance the heart must overcome to eject blood (like blood pressure or vessel constriction).

Shock - Signs and Symptoms

Shock presents with cool, clammy skin; weak, rapid pulse; altered mental status; hypotension; and tachypnea. It indicates inadequate tissue perfusion. (fever if its septic)(bradycardia and warm skin if neurologic)

Shock - Vital Signs

Typically: low blood pressure, rapid heart rate, rapid or shallow breathing, narrow pulse pressure, and weak peripheral pulses.

Types of Shock

Hypovolemic (blood loss), Cardiogenic (heart pump failure), Obstructive (blockage such as tamponade or tension pneumothorax), and Distributive (anaphylactic, neurogenic, septic).

Causes of Cardiogenic Shock

Usually due to myocardial infarction or severe heart failure leading to pump failure and reduced cardiac output.

Compensated vs Decompensated Shock

Compensated shock: body maintains perfusion via tachycardia and vasoconstriction; patient may appear anxious or pale. Decompensated shock: body can no longer maintain BP; hypotension and altered LOC appear.

Shock Treatment

Focus on stopping the cause (e.g., bleeding, infection), providing oxygen, maintaining body temperature, and rapid transport. Cardiogenic shock requires caution with fluid resuscitation.

Congestive Heart Failure - Right Sided

Causes systemic congestion: JVD, peripheral edema, and ascites due to fluid backup into the venous system.

Congestive Heart Failure - Left Sided

Causes pulmonary congestion: crackles, dyspnea, orthopnea, and pink frothy sputum due to fluid backing up into the lungs.

Pulmonary Edema

Fluid accumulation in alveoli; causes hypoxia and crackles (rales). The “wet” lung sound indicates fluid and is common in left-sided heart failure.

Hypertension Crisis

Extremely high BP (>180/120) causing headache, vision changes, chest pain, or neurological deficits; can lead to stroke or organ damage.

Myocardial Infarction

Death of heart tissue from ischemia due to coronary artery blockage. Presents with chest pressure, diaphoresis, nausea, and sometimes silent in DIABETICS or FEMALES.

Angina Pectoris - Stable

Predictable chest pain during exertion that resolves with rest or nitroglycerin.

Angina Pectoris - Unstable

Unpredictable pain occurring at rest or with minimal exertion, may not resolve with nitroglycerin; warning sign for MI.

Myocardial Infarction vs Angina Pectoris

MI pain is more severe, lasts longer, and is not relieved by rest or nitroglycerin, while angina is temporary and reversible.

Stroke - Ischemic

Caused by blockage in a cerebral artery; symptoms include facial droop, slurred speech, weakness on one side.

Stroke - Hemorrhagic

Caused by rupture of a cerebral vessel; presents with sudden severe headache, nausea, and rapid LOC decline.

Embolism

A clot or other object that travels through circulation and blocks a smaller vessel, cutting off blood flow.

Thrombosis (DVT)

Formation of a blood clot in a deep vein, often in the leg; risk of pulmonary embolism if it dislodges.

Syncope

Temporary loss of consciousness due to transient decrease in cerebral perfusion; often caused by hypotension or vagal stimulation.

Hypotension

Abnormally low blood pressure; causes include shock, dehydration, or medication. Leads to poor tissue perfusion.

Dysrhythmias

Abnormal heart rhythms such as bradycardia, tachycardia, or ventricular fibrillation. EMTs focus on those that affect perfusion.

Aneurysm

Ballooning of a blood vessel wall that can rupture (life-threatening) or dissect (tears within the wall causing sharp chest/back pain).

AAA (Abdominal Aortic Aneurysm)

Major red flags: tearing abdominal/back pain, pulsating abdominal mass, hypotension, and unequal femoral pulses.

CAD (Coronary Artery Disease)

Narrowing of coronary arteries due to plaque buildup (atherosclerosis), reducing blood flow and causing angina or MI.

ACS (Acute Coronary Syndrome)

Group of conditions from myocardial ischemia (unstable angina, NSTEMI, STEMI). Sudden onset, pressure-like chest pain radiating to jaw or arm, with diaphoresis and nausea.

Aortic aneurysm

weakens the wall of the aorta , making it susceptible for rupture.

Aortic aneurysm S/S

very sudden chest pain, comes on full force, different blood pressure

Dissecting aneurysm

occurs when inner layers of aorta become separated, the primary cause of this is uncontrolled hypertension (tear)

Rupture aneurysm

a weakened area in a blood vessel that bursts, causing bleeding into the surrounding tissues (balloon pop)

stroke S/S (FAST acronym)

face droop, arm weakness, speech difficulty, time (when symptoms began) // confusion, dizziness, loss of balance

stroke treatment

ABCs, provide oxygen if spo2 < 94%,

be quick, they need fibrinolytic therapy in the first 3 hours

Pulmonary edema s/s

Severe dyspnea, crackles/rales, frothy sputum, orthopnea, cyanosis

AMI presents strangely in what demographic

women with diabetes

common ED drugs (contraindication for nitro)

sildenafil [Viagra], vardenafil [Levitra], tadalafil [Cialis])

pain associated with ACS

feeling of pressure or heaviness, discomfort, or a crushing pain

Pain associated with conditions such as pulmonary embolism or spontaneous pneumothorax

Stabbing or sharp (pleuritic)

what is a is an hemorrhagic stroke

When a blood vessel in the brain ruptures, it bleeds into or around brain tissue

S/S & treatment of hemorrhagic stroke

sudden severe headache, seizures, decreased level of consciousness, (bradycardia, hypertension, irregular respirations) = Cushing’s triad and unequal pupils in extreme cases

Visceral vs parietal

visceral = lining around organ

parietal = attaches organ to body

S/S of meningitis

fever or chills, severe headache, stiff neck(nuchal rigidity), sensitivity to light

(infant = bulging fontanelle, poor feeding, irritability)

how an AMI differs from angia pain

ami is not always due to exertion, lasts 30 min to an hour, not always relieved with nitroglycerin, and Ami patients may not realize they are having a heart attack

OQRST of ami

O - gradual w/ additional symptoms

Q - tightness or pressure

S - increases with time

T - may come and go

R- substernal; back rarely

peripheral pulses equal

OQRST of dissecting aneursym

O - abrupt w / additional symptoms

Q - SHArp and tearing

S - max severity all the time

T - does not stop

R - back possibly involved with shoulder blades

difference between peripheral pulses

what’s the beck’s triad and what does it indicate

hypotension, JVD, and muffled heard sounds (due to fluid surrounding heart)

indicates cardiac tamponade

Ejection fraction

the percentage of blood pumped out of the heart's left ventricle with each contraction (55-70%

Sterlings law

the heart's force of contraction increases with ventricular stretch, meaning that the more the heart fills with blood, the stronger its contraction and the greater the stroke volume will be

Contractility

the ability of muscle tissue to shorten and generate force, but it most commonly refers to the heart's ability to forcefully contract and pump blood

Arteriosclerosis

Hardening of arterial walls preventing vasoconstriction and vasodilation