Chapter 19: Heart Failures and Dysrhythmias

heart failure

the heart is too weak or too stiff to pump enough blood to meet the body’s / organ systems needs

• Clinical syndrome resulting from a primary condition which inhibits the heart’s ability to maintain sufficient cardiac output

• Heart is unable to provide sufficient cardiac output

• Affects multiple organ

• Progressive

cardiac output

amount of blood the heart pumps in one minute

cardiac dysthymias

(irregular heartbeats)

are problems with the hearts electrical system that cause the heart to beat too fast, too slowly, or irregularly (abnormalities in the heart’s electrical activity)

diagnosis of HF

based on the presence of a constellation of signs and symptoms that are characteristics of the syndrome

criteria for diagnosis

• Dyspnea

• Pulmonary rales

• Cardiomegaly

• Pulmonary edema

• S3 heart sound

• Tachycardia

classification of HF

1. right sided

2. left sided

3. biventricular

4. heart failure with low ejection fraction (HFrEF)

5. heart failure with preserved ejection fraction (HFpEF)

HF class

New York Heart Association (NYHA).

• Class I to IV

stage progression of HF

American Heart Association (AHA)

• Stage A to D

heart failure with low ejection fraction (HFrEF)

patients with HF that have significant systolic dysfunction

• classifies HF by the ability of the heart to eject blood from the ventricles or to relax and fill with blood during systole

heart failure with pressed ejection fraction (HFpEF)

patients with symptoms of HF with a normal ejection fraction

• classifies HF by the ability of the heart to eject blood from the ventricles or to relax and fill with blood during systole

Heart failure cm

"FACES" for key HF symptoms:

• F - Fatigue

• A - Activity limitation

• C - Congestion

• E - Edema

• S - Shortness of breath

• orthopnea

• fluid retention

• cognitive changes

compensatory mechanisms

• Sympathetic nervous system (SNS) activation

  • heart rate, contractility, arterial vasoconstriction, and renin release

• Increased preload – initially

  • Then decreased cardiac output

• Myocardial Remodeling and Progression

  • Chronic elevation of myocardial wall tension

left sided heart failure

occurs when the left ventricle cannot pump blood effectively to the rest of the body, when left side of the heart fails, blood can back up into the lungs, causing fluid buildup and difficulty breathing

(left = lungs / breathing problems)

causes of left sided heart failure

1. left ventricular infarction (heart attack, damages LV making it weaker and less able to pump blood)

2. valvular heart disease (heart values don’t open or close properly = harder pumping)

3. systemic HTN (high BF forces LV to work harder)

backward effects of LSHF

blood backs up into the lungs b/c the left side of heart cannot pump it forward effectively

• can cause pulmonary congestion and pulmonary edema

pulmonary edema

(fluid builds up in the lungs, especially air sacs)

pulmonary congestion

(too much blood and fluid in lung circulation)

forward effects

heat cannot pump enough blood forward to supply body’s organs and tissues with oxygen and nutrients

• Acute cardiogenic pulmonary edema: life-threatening condition severely impairs gas exchange

• Severe dyspnea and anxiety, increase HR

• Straight upright posture - maximize respiratory effort

right sided heart failure

happens when the right ventricle cannot pump blood effectively to lungs when right side becomes weak, blood backs up into the body’s veins causing fluid buildup and swelling

(RIGHT = REST OF BODY, swelling and fluid backup)

• comes after left side failure, b/c increase in pressure in lungs = right side compensation to push blood into lungs = RV becoming weak

• congestion of blood and inefficiency of the pump

congestion of blood and inefficiency of the pump

blood backs up b/c RV cannot pump forward, RV is not pumping blood effectively

• RV becomes weak = blood cannot move into lungs = blood blocking the veins throughout body which then causes

  • peripheral edema - swelling in legs, ankles, ascites - fluid buildup in the abdomen

  • JVD distention - bulging neck veins

  • hepatomegaly - enlarged liver

RSHF pulmonary disorders

(isolated right ventricular failure - rare occurrence)

• increased pulmonary vascular resistance - blood has difficulty flowing through blood vessels in lungs

• high afterload - resistance in lungs increase, RV has to work harder

• right ventricular hypertrophy - RV becomes thicker cus its working harder

• (cor pulmonale)

• right ventricular failure

cor pulmonale

lung disease causes right side failure, RS becomes enlarged or strained bc of high pressure in blood vessels in lungs caused by lung disease

backward effects of RSHF

blood backs up into the body’s veins b/c right ventricle cannot pump it forward effectively (systemic venous congestion)

• impaired function of the liver, portal system, spleen, kidneys, peripheral subcutaneous tissues, and brain; impaired mental functioning, hepatomegaly, splenomegaly

forward effects of RSHF

low cardiac output

biventricular heart failure

happens when BOTH the left and right sides of the heart failing the heart cannot pump blood effectively to the lungs or the rest of the body

• Most often a result of primary left ventricular failure - progressed to right-sided HF

• Reduced cardiac output

• Pulmonary congestion - left-sided HF

• Systemic venous congestion - to right-sided HF

heart failure treatment

• Improve cardiac output

• Minimize congestive symptoms

• Minimize cardiac workload

• Prevent progression

medications classification

• ACEIs, ARBs, aldosterone antagonists, and some β1- blocking agents

  • ACEIs and ARBs drug classes - standard therapy

• Diuretics

• Positive inotropic drugs

• Digitalis (or a related cardiac glycoside)

• Pacemakers

• Improvement of etiologic factors

cardiac dysthymias

• Abnormalities in impulse generation or conduction.

• Can be benign or life- threatening (e.g.,ventricular fibrillation).

• May arise from ischemia, electrolyte imbalance, or drug toxicity

types of dysthymias

• Atrial fibrillation

• Ventricular tachycardia

• Heart blocks

• Premature beats

dysrhythmias cm

• Palpitations or skipped beats

• Dizziness, syncope, or fatigue

• Shortness of breath or chest discomfort

• Sudden cardiac arrest in severe cases

diagnosis of dysrhythmias

• 12-lead ECG

• Holter monitoring

• Event recorders

• Electrophysiology studies

management of dysrhythmias

• Pharmacologic: beta-blockers, calcium channel blockers

• Electrical cardioversion

• Ablation therapy and pacemaker implantation

• Defibrillation

• Lifestyle modifications

• Regular monitoring and follow-up

interrelationship between HF and dysrhythmias

• Heart failure increases risk of atrial and ventricular arrhythmias.

• Dysrhythmias worsen cardiac output.

• Treat both conditions concurrently