Cardiac Lecture PPT. pt. 2 - Mrs. Allison

Causes of Hypertension (HTN)

-increase in fluid in normal BV
-normal fluid in NARROW BV
-modifiable, non-curable, factors of CVD

Causes of primary hypertension

-genetic + epigenetic factors

-obesity, sedentary lifestyle, poor diet (too much salt, not enough nutrients)

-alcohol, cigarettes

-chronic stress

-population

-factors with age and gender

Factors with age and gender linked to hypertension

-hypertension increases with age

-men are at higher risk earlier; women have HIGHEST risk increases post-menopause

-women premenopause are at the lowest risk

2 Major Pathological effects of hypertension

1) high shearing stress on arterial walls

2) LV hypertrophy (LVH)

Effects of hypertension, specifically on arterial walls

high shearing stress from HTN on arterial walls is linked to:

injury to retina, kidneys, brain, lower extremities

Why is hypertension linked to Left Ventricular Hypertrophy (LVH) ?

coronary blood supply is unable to support additional ventricular tissue

*the left ventricle has high oxygen demands

Secondary Hypertension

caused by a systemic disease process that elevates BP as a side effect

4 Things that can cause Secondary Hypertension

1) Renal artery stenosis

2) Hyperthyroidism (graves)

3) Illegal drug use

4) Obstructive sleep apnea

HTN effects on Cardiac

LVH, heart failure

HTN effects on Renal

tissue damage, nephrosclerosis

HTN effects on Brain

TIA (transient ischemic attack), CVA (stroke), dementia

HTN effects on Eyes

retinal damage

HTN effects on Aorta

Aneurysm

Major causes of heart failure

-Ventricular hypertrophy → (ex: chronic HTN w/ 75% of cases!)

-Repeated ischemic heart episodes

-Nonischemic causes

-Dysrythmias

-Valvular disorders

-COPD

Left Ventricular Ejection Fraction (LVEF)

the volume of blood pumped with each ventricular contraction

In healthy individuals, ? to ? % of blood volume in the left ventricle is pumped with each contraction. (LVEF)

60-70%

A LVEF of lower than ? % is considered heart failure.

40%

Left Heart Failure aka. CHF

a condition where the left side of the heart cannot pump blood effectively, leading to fluid buildup in the lungs and other tissues

2 types of Left heart failure/CHF

Systolic and diastolic

Systolic heart failure

-heart failure with reduced Ejection Fraction (EF) aka. systolic function

-inability to perfuse tissues w/ CO

causes: MI, HTN, recurrent ischemia

Diastolic heart failure

-heart failure w/ preserved Ejection Fraction (EF) aka. systolic function

-Pulmonary congestion bc of stiff LV and lack of filling

In a healthy individual with HIGH preload, this = HIGH SV and HIGH CO. How is this different in someone with Systolic HF?

high preload will overwhelm the weakened pump, so SV is LOW and CO is LOW.

In a healthy individual with HIGH preload, this = HIGH SV and HIGH CO. How is this different in someone with Diastolic HF?

The ventricle is stiff and unable to stretch → increased volume causes increased ventricular pressure/backward congestion (often pulmonary congestion).

The Frank-Starling Law

states that the stroke volume of the heart increases in response to an increase in the volume of blood filling the heart (preload) when all other factors remain constant

High systemic vascular resistance (Systemic HTN) creates HIGH afterload for the …. ????

Left Ventricle (LV)

High pulmonary vascular resistance (Pulmonary hypertension) creates HIGH afterload for the ….???

Right Ventricle

2 Types of Left Heart Failure

1) Inadequate Perfusion = forward failure

2) Pulmonary Congestion = backward failure

Inadequate Perfusion “forward failure”

LT HEART FAILURE WHERE NOT ENOUGH BLOOD IS GETTING TO THE BODY

Inadequate Perfusion symptoms

-fatigue, disorientation, hypotension (sometimes hypertension)

*the RAAS releases ADH to retain water to try and increase blood vol

-cyanosis

Pulmonary Congestion “backward failure”

LT HEART FAILURE WHERE BLOOD BACKS INTO THE LUNGS

Pulmonary Congestion symptoms

– Dyspnea

– Orthopnea, Paroxysmal Nocturnal Dyspnea (PND)

– Pulmonary edema (cyan, inspir. crackles, pleural

effusions)

– Pink, frothy sputum (severe pulmonary edema)

Right Heart Failure

the right ventricle is a LOWER pressure pump and cannot pump as much blood out to the pulmonary artery as the LV can.

Right Heart Failure is most commonly caused by…

COPD - hypoxic pulmonary disease

How does COPD (hypoxic pul. disease) cause Right Heart Failure?

1) constriction of the pulmonary artery causes HTN, increasing resistance that the Right Ventricle has to pump against.

2) This causes Right Ventricular Hypertrophy.

3) Backs up into peripheral system.

Summary of effects of Right Ventricular Failure (RVF)

-Jugular vein distension (JVD)

-ascites and edema

-anasarca = massive edema

-weight gain from fluid

-hepatomegaly

-splenomegaly

Brain Natriuretic Peptide (BNP)

Increased blood vol. leads to increase ventricular vol. + stretch

-ventricular myocytes then release BNP

-higher BNP = more severe HF = higher death risk

Brain Natriuretic Peptide (BNP) promotes the excretion of what 2 things???

Na+ and Water

-reduces blood vol. (preload) and lowers BP

Peripheral Artery Disease (PAD)

a condition involving reduced blood flow through the peripheral arteries

Reynaud Phenomenon

Episodic vasospasm in the arterioles of the fingers

*less commonly in the toes sometimes

-white, then blue fingers and toes

Reynaud Disease

A primary vasospastic disorder thought to be caused by an exaggerated sympathetic nervous system (SNS) response, leading to vasoconstriction.

Claudication

a common symptom of Peripheral Artery Disease (PAD)

characterized by leg pain with walking, relieved by rest

Varicose veins

a vein in which blood has pooled

-distended, tortuous, palpable veins

Risk factors for Varicose veins

-age, female sex, family history, obesity, pregnancy

Varicose vein causes

-trauma

-gradual venous distention

-high pressure within superficial veins that weaken vein valves

-prolonged standing or sitting

-pregnancy

-obesity

Venous ulcers form due to…

capillary damage and inflammation lead to endothelial damage, platelet aggregation, and intracellular damage

Characteristics of venous ulcers

-irregular and shallow

-commonly forms on the ankle area above the medial malleolus

Deep Vein Thromboembolism (DVT)

blood clot forms in a deep vein,

-blocking blood flow, leading to increase in venous pressure

-can lead to Pulmonary Embolism (PE) aka. when the clot travels to the lungs

Virchow’s Triad - 3 things that risk getting a blood clot

1) Venous stasis = blood isnt moving normally

2) Vascular damage = inner lining of a BV is damaged

3) Hypercoagulability = increased ability to clot bc too active

Heart Failure (HF)

weakening of a ventricular muscle that is unable to sufficiently pump blood to meet the needs of tissues

Hypertrophic cardiomyopathy

genetic condition, can be found in young, healthy adults

has excess tissue that can obstruct blood flow in the heart

Atherosclerosis

chronic condition associated w/ plaque buildup → #1 cause of CAD

hardening of the arteries, associated w/ chronic HTN

COPD

a major cause of heart failure.

-chronic hypoxia (low oxygen) → leads to increased arterial pressure

places strain on the RIGHT VENTRICLE

Healthy LVEF

60-70%

LVEF lower than __% is considered heart failure

40%

Echocardiogram (ECG/EKG)

-used to view the heart structurally → can make measurements

*can detect stenosis

*used to measure LVEF

Systole = “squeeze”

contracting

Diastole

relaxing / filling

Preload =volume

volume of blood in the ventricle at the end of diastole (before contraction!)

It is the degree of stretch of the LV.

For a healthy individual with HIGH preload, how are SV and CO affected?

SV and CO will both be high.

For a healthy individual with LOW preload, how are SV and CO affected?

SV and CO will both be low.

In SYSTOLIC (pump) HF, high preload overwhelms the weakened pump.

SV is ?. CO is ?.

SV is decreased. CO is decreased.

In DIASTOLIC (filling) HF, high preload is unable to stretch the ventricle. The increased volume causes ???.

backflow

Afterload

Resistance needed to overcome to eject blood from LV (systole)

HIGH systemic vascular resistance (systemic HTN), creates HIGH afterload for…

Left Ventricle (LV)

HIGH pulmonary vascular resistance (pulmonary HTN) creates HIGH afterload for…

Right Ventricle (RV)

Inadequate perfusion in SYSTOLIC heart failure will have what symptoms?

fatigue, HTN, (or sometimes HYPOtension)

-RAAS and post pituitary will DECREASE urine output (uop)

-Cyanosis

Why in Systolic HF, if experiencing inadequate perfustion, will the RAAS + post pituitary gland decrease uop?

to conserve water + sodium to help the blood pressure and maintain circulation.

Inadequate perfusion in DIASTOLIC heart failure will have what symptoms?

-dyspnea

-orthopnea, paroxysmal nocturnal dyspnea (PND)
-pul. edema

-pink, frothy sputum ( severe pulmonary edema )

Pink, frothy sputum is ICONIC for…

Severe pulmonary edema!

*extremely high hydrostatic pressure

Acute

sudden condition

Chronic

long-standing condition or illness

Jugular Vein Distension (JVD)

HP > OP

*effect of Right Ventricular Failure

causes bulging of the jugular veins due to increased central venous pressure

Why is weight gain from fluid a common effect of Right Ventricular Failure

due to the inability of the RV to effectively pump blood, leading to increased venous pressure and fluid retention in the body.

Hepatomegaly

enlargement of the liver, often due to CHF spef. RVF

Splenomegaly

englargement of the spleen, often due to CHF… specifically RVF

With fluid volume overload, there is a increased ventricular vol. + stretch.

What do ventricular myocytes release?

BNP → brain natriuretic peptide

high BNP = the more severe the HF is

What does BNP promote the excretion of?

Na+ and water

“diuresis”

= reduces blood vol. (spef. preload) + BP

Claudication (pain w/ ambulation, relieve w/ rest) is a common sign of…

PAD → It results from insufficient blood flow to the muscles during physical activity.

Venous ulcers are complications of…

-Venous insufficiency

-and/or Varicose Veins

Varicose veins are due to..

incompetent valves cause blood pooling

-prolonged standing/sitting, pregnancy, obesity, etc.

****Virchow’s Traid = 3 factors that contribute to DVT clot formation

1) Venous stasis

2) Vascular damage

3) Hypercoagulability

Vascular Damage/Vascular wall inj. causes

-trauma/surgery

-venepuncture

-chem. irritation (chemo)

-heart valve disease / replacement

-atherosclerosis

-indwelling catheters

Hypercoaguability causes

-Malignancy

-Pregnancy + peri-partum period

-estrogen therapy

-trauma, surgery of lower extremity

-inflammatory bowel disease

-nephrotic syndrome

-sepsis

-thrombophilia

Venous Stasis (aka circulatory stasis) causes

-A fib

-LV dysfunction

-immobility / paralysis

-venous insufficiency / varicose veins

-venous obstruction: tumor, obesity, pregnancy