PULSE - Case 3

PULSE - Case 3

One too many WhoppersOne too many Whoppers

Josh Laird - MS II - jlaird1@hmc.psu.edu

Rob Freed - MS II - rfreed@hmc.psu.edu

Penn State College of Medicine

Milton S. Hershey Medical Center

O2 is important!O2 is important!

Allows aerobic respiration to occur More ATP is made This gives muscle energy Keeps muscles alive!

Allows aerobic respiration to occur More ATP is made This gives muscle energy Keeps muscles alive!

Which areas need O2 the most?

Which areas need O2 the most?

The Heart! Myocytes are constantly contracting and

burning ATP, they can’t live in anaerobic respiration

Can you think of other critical organs that need O2?

The Heart! Myocytes are constantly contracting and

burning ATP, they can’t live in anaerobic respiration

Can you think of other critical organs that need O2?

How is the heart perfused?How is the heart perfused?

Through the coronary ostia and into the coronary arteries!

When is the heart perfused? Systole or diastole?

Through the coronary ostia and into the coronary arteries!

When is the heart perfused? Systole or diastole?

What are these?

Sinus of Valsalva

Left Coronary ostium

Valve leaflets

Right Coronary ostium

Sinus of Valsalva

Systole

Diastole

Left Anterior Descending Artery

Right Coronary Artery

Circumflex Artery

Coronary Occlusion Areas at Risk Left Coronary

Artery

Can we model heart perfusion?

Can we model heart perfusion?

Q = ΔP R

Q = coronary flow (perfusion) P = pressure R = coronary resistance)

What does this mean? Changes in these can cause ↑ or ↓ perfusion

There are many things that can change these parameters, we will only focus on one.

Q = ΔP R

Q = coronary flow (perfusion) P = pressure R = coronary resistance)

What does this mean? Changes in these can cause ↑ or ↓ perfusion

There are many things that can change these parameters, we will only focus on one.

What can change R?What can change R?

Exercise

VSD ↑ wall thickness (ventricular hypertrophy) Compresses the coronary arteries ↓ filling and thus, ↓ perfusion

Coronary artery disease! ↓ arterial diameter obstructs flow & ↑

resistance

Exercise

VSD ↑ wall thickness (ventricular hypertrophy) Compresses the coronary arteries ↓ filling and thus, ↓ perfusion

Coronary artery disease! ↓ arterial diameter obstructs flow & ↑

resistance

What is coronary artery disease?

What is coronary artery disease?

The #1 cause of death! Every 26 seconds, someone in the

US will have a coronary event (>120 people by the end of this lecture)

770,000 Americans will have a new coronary attack this year alone

430,000 will have a recurrent attack

The #1 cause of death! Every 26 seconds, someone in the

US will have a coronary event (>120 people by the end of this lecture)

770,000 Americans will have a new coronary attack this year alone

430,000 will have a recurrent attack

What is atherosclerotic plaque?

What is atherosclerotic plaque?

Atherosclerosis “hardening of the

arteries”1) endothelial dysfunction2) Fat accumulation (LDL)3) Recruitment of

leukocytes (white blood cells)

4) Smooth muscle cells grow over the lipid

5) This forms what we call a plaque

Atherosclerosis “hardening of the

arteries”1) endothelial dysfunction2) Fat accumulation (LDL)3) Recruitment of

leukocytes (white blood cells)

4) Smooth muscle cells grow over the lipid

5) This forms what we call a plaque

Atherosclerosis dev’ps over time

Atherosclerosis dev’ps over time

“fatty streaks” as young as age 5 “fatty streaks” as young as age 5

The Leukocyte Paradox!The Leukocyte Paradox! Normally, white blood cells are good! How are

they bad in CAD? These release degradative chemicals to try to

remove the lipid in the artery These make “foam cells”

Like churning butter, becomes fluffy and ‘foamy’ This is the first visible lesion in atherosclerosis

Normally, white blood cells are good! How are they bad in CAD?

These release degradative chemicals to try to remove the lipid in the artery

These make “foam cells” Like churning butter, becomes fluffy and ‘foamy’

This is the first visible lesion in atherosclerosis

2 types of plaques2 types of plaques Vulnerable

Stable

Vulnerable

Stable

How does this relate?How does this relate?

Can get stenosis (narrowing of the coronary arteries

Amount of damage depends on the location and extent of blockage

Time of ischemia is vitally important

Arteries need to be blocked >40% to get symptoms

Can get stenosis (narrowing of the coronary arteries

Amount of damage depends on the location and extent of blockage

Time of ischemia is vitally important

Arteries need to be blocked >40% to get symptomsYou mean I can have blockages without knowing it?

YES!

Large damaged area

Small damaged area

Near

Far

Collaterals

Proximal

Distal

I’d like to introduce you to Mr. Bryant

For our purposes, let’s reduce Mr. Bryant down to the bare minimum!

Mr. Bryant suddenly suffers a heart attack due to a blocked coronary artery… this limits blood flow to the heart muscle

Sensory nerves within heart tissue sense the chaos and “send word” to the brain of the havoc!

The nerve signals to his brain cause severe pain in his chest!

The nerve signals to his brain cause severe pain in his chest!

So, Mr. Bryant has chest pain,

but why do most people ALSO describe intense pain in their left arm?!

“Referred Pain”“Referred Pain” Referred pain is a term used to

describe the phenomenon of pain perceived at a site adjacent to or at a distance from the site of an injury's origin. One of the best examples of this is during ischemia brought on by an angina pectoris, or heart attack. Even though the heart is directly affected the pain is often felt in the neck, shoulders and back rather than the chest. The International Association for the Study of Pain, as of 2001, has not officially defined the term; hence several authors have defined the term differently. Despite an increasing amount of literature on the subject there is no definitive answer regarding the mechanism behind this phenomenon. This phenomenon is also known as "reflective pain"[1]

Physicians and scientists have known about referred pain since the late 1880s yet the true origins and causes of referred pain is unknown.

Referred pain is a term used to describe the phenomenon of pain perceived at a site adjacent to or at a distance from the site of an injury's origin. One of the best examples of this is during ischemia brought on by an angina pectoris, or heart attack. Even though the heart is directly affected the pain is often felt in the neck, shoulders and back rather than the chest. The International Association for the Study of Pain, as of 2001, has not officially defined the term; hence several authors have defined the term differently. Despite an increasing amount of literature on the subject there is no definitive answer regarding the mechanism behind this phenomenon. This phenomenon is also known as "reflective pain"[1]

Physicians and scientists have known about referred pain since the late 1880s yet the true origins and causes of referred pain is unknown.

WHAAT!?WHAAT!?

Referred Pain for Dummies! (more like: for everyone who likes the KISS method)

Look at how close the nerves from the arm and the heart are!

The brain, not as smart as some may think… forgets where the ACTUAL pain came from…

Therefore, the individual feels pain in both chest AND shoulder/arm

Levine SignLevine Sign The Levine Sign

is a clenched fist held over the chest to describe the tightening or pressure felt during a heart attack

The Levine Sign is a clenched fist held over the chest to describe the tightening or pressure felt during a heart attack

You’re an emergency room doc and these two patients come

in…

You’re an emergency room doc and these two patients come

in… Michelle Smith,

a 46 year old female from York presents with mild chest pressure and nausea

Michelle Smith, a 46 year old female from York presents with mild chest pressure and nausea

Michael Smith, a 45 year old male presents to you with chest pain, radiating to his left arm and is sweating profusely

Michael Smith, a 45 year old male presents to you with chest pain, radiating to his left arm and is sweating profusely

Variable symptoms of heart attacks…Variable symptoms of heart attacks…

WomenLess severe chest painMore shortness of breath, vomiting, nausea

WomenLess severe chest painMore shortness of breath, vomiting, nausea

MenMore severe chest painSweaty

MenMore severe chest painSweaty

Regardless of gender, if a patient has a heart attack, despite symptoms that the patient has, it is VERY SERIOUS!

Some people will come to the ER with chest pain

Some people will drop dead while doing yardwork

Some may never have symptoms and never know of their heart attack

Some people will come to the ER with chest pain

Some people will drop dead while doing yardwork

Some may never have symptoms and never know of their heart attack

Variable outcomes of heart attacks…Variable outcomes of heart attacks…

Therapy for heart attack/Ways to prevent heart attacks from even happening!

Therapy for heart attack/Ways to prevent heart attacks from even happening!

Will be the topic of discussion for November 19th (no lecture next week)

Will be the topic of discussion for November 19th (no lecture next week)

Primary prevention: Everyone can utilize primary prevention by… eating healthy, exercise

Secondary prevention (you’re at a higher risk of heart attack, what now?): Drugs! Cholesterol lowering drugs! Blood pressure controlling drugs!

Tertiary prevention(you’ve had a heart attack, what can be done to limit the damage?): Angioplasty, CABG, Stent placement, etc.

Primary prevention: Everyone can utilize primary prevention by… eating healthy, exercise

Secondary prevention (you’re at a higher risk of heart attack, what now?): Drugs! Cholesterol lowering drugs! Blood pressure controlling drugs!

Tertiary prevention(you’ve had a heart attack, what can be done to limit the damage?): Angioplasty, CABG, Stent placement, etc.

Thank you!Thank you!

Questions?

Comments?

Thoughts?

Questions?

Comments?

Thoughts?