Sprowls Content

About ___ million people over the age of 20 have heart failure and is expected to exceed ____ million by 2030.

65; 8

How many new heart failure cases are there each year

960,000

Roughly 50% of people who develop HF die within

5 years

Do women or men have a higher mortality rate

women

HF defintion

the heart’s inability, particularly the ventricles to pump enough blood to meet the body’s metabolic demands

left ventricle

blood to body

right ventricle

blood to lungs

HF can be caused by any disorder that affects the heart’s ability to either ____ or ____ blood

receive; pump

Multiple pathogens can accelerate process including

atherosclerosis, dyslipidemia, diabetes, myocardial infraction, thyroid disorders, chronic hypertension, mitral stenosis

Left Heart Failure

Decreased ability of the left ventricle to either contract (systole) or fill (diastole)

Right Heart Failure

Decreased ability of the right ventricle to either contract (systolic) or fill (diastolic)

High output heart failure

Characterized by increased cardiac output, but low systemic vascular resistance (dilations of blood vessels)

Systolic LHF

-Caused by decreased contractility of the left ventricle

-Damage to the myocardium are the primary cause of decrease: MI, dilated cardiomyopathy, myocarditis

-Decreased contractility leads to decreased left ventricular ejection fraction called heart failure with a reduced ejection fraction.

-Left ventricle becomes dilated or enlarged causing increased volume of blood contained within

Diastolic LHF

-Caused by decreased ability of the left ventricle to fill appropriately.

-Conditions that impart systemic vascular resistance commonly lead to diastolic LHF: Hypertension, aortic stenosis, hyperhoptic cardiomyopathy

-An inability to overcome the pressure needed to push blood throughout (afterload) the body causes hypertrophy of the left ventricle, narrowing the volume within

-While stroke volume might be decreased, the LVEF in these patients is preserved or normal and termed heart failure with a preserved injection fraction. Typically >50%.

Pulmonary Congestion

-Decreased ability of the heart to eject blood causes a buildup in the heart that can translate backwards leading to pulmonary congestion and increased pulmonary capillary wedge pressure (PCNP)

-The end result of this fluid buildup in the lungs leading to pulmonary edema making it hard to breath, particularly when exercising or laying down.

-Can lead to hypoxia if pulmonary edema becomes severe

Cardiogenic Shock

-Decreased CO caused by LHF causes decreased systemic perfusion leading to organ malperfusion.

-Extremities may present as cold and pale with molting.

-Can lead encephalopathy, TIA/CVA, myocardial infraction, acute kidney injury, acute mesenteric ischemia, and buildup of lactate (lactic acidosis).

What is the pathophysiology related to right heart failure

Commonly caused by an inability of the right ventricle to appropriately efficiently pump blood whether by contraction or volume

Systolic RHF

-Caused by decreased contractility of the right ventricle

• Really only caused by MI of the right ventricle myocardium, but plausible damage to the myocardium for any reason can also be the etiology of RHF.

-Decreased contractility leads to decreased right ventricular ejection fraction

Diastolic RHF

-Caused by decreased ability of the right ventricle to fill appropriately

-Conditions that impart an increase in pulmonary vascular resistance commonly lead to diastolic RHF: pulmonary hypertension, embolism, lung disease, LHF

-An inability to overcome the pressure needed to push blood into the lungs causes hypertrophy of the right ventricle narrowing the volume within.

-While stroke volume might be decreased, the RVEF in these patients is normal, or preserved

What are the complications that result right heart failure

-Most deterimental complication is increased control venous pressure or the pressure experienced in the large veins and right atrium.

-Increased CVP presents in: Pitting Edema and Jugular vein dissension

-As blood is continually backed up particularly from the liver emptying into the inferior vena cava the liver can become congested and lead to liver failure.

-Portal vein hypertension can lead to capillary leak of the mesenteric vessels resulting in fluid buildup in the peritoneum or ascites

-While uncommon it is possible that extreme dilation of the right ventricle can cause a septal shift where the right ventricle becomes so enlarged it collapses the volumetric space of the left ventricle

HOHF is caused by

extreme vasodilation of the systemic vasculature

What is the pathophysiology related to high output heart failure

-Because of the vasodilation, the total peripheral resistance is going to drop, lowering BP, causing the body to compensate by activating the SNS in an effort to raise BP.

-In the heart specifically, this is going to increase HR and SV.

-This will increase CO, but is insufficient to overcome the minimal TPR, and will be in a constant downward spiral of the body trying to increase its CO

What are the compensatory mechanisms that lead to worsening heart failure

-Baroreceptors are activated due to low MAP activating the SNS, and signals to vasomotor center and cardio accelerator center, causing increased heart rate, stroke volume, and vasoconstriction.

-Decreased CO leads to decreased pressure sensed by th eJG cells of the kidney, and initiates the RAAS.

-Atrial stretch causes release of ANP from the left atrium, which is going to try to inhibit the actions of AT-II in an attempt to offset RAAS activation but eventually fails.