Congestive Heart Failure
- Hearts inability to meet body's normal circulatory demand
- There are various causes of Congestive Heart Disease
- Heart failure might be asymptomatic on mild exertion
- Could be due to Systolic or Diastolic dysfunction

Systolic dysfunction (Pump dysfunction)
- Decreased ejection fraction
- Due to 
i. Obstruction of flow (eg in aortic stenosis)
ii. Contractility dysfnx (eg in LV hypertrophy)

Causes of Systolic Dysfunction

Common causes
1. Hypertension
2. Myocardial Infarction
3.Valvular diseases
4. Myocarditis

Less common causes (HART)
1. Hemochromatosis
- Excessive deposition of iron in cardiac muscles inorder of Epicardium, Myocardium and Endocardium
- Catalyzed by the rapid Fenton reaction to hydroxyl ions (ROS) 
- ROS cause Leak of hydrolytic enzymes which initiate cell damage 
- Hemochromatosis can accelerate ischemia-induced reperfusion injury 
- Process is reversable

2. Alcohol overuse
- LV myocyte loss, -ve inotropy and depressed contractility  
- myocyte dysfunction (abnormal calcium homeostasis) 
- Increased LV dilation/Mass and/or reduced wall thickness (Dilated cardiomyopathy) 

3. Radiation
- Acute and chronic effects on the heart.
- Acute effects by TNF, IL-1, 6, and 8 plus neutrophil infiltration. (asymptomatic/pericarditis)
- Chronic effect induces fibrosis (IL-4, IL-13, and TGF-β)
- A decrease in elasticity and distensibility
- Endothelial damage (fibrotic changes), lipid and inflammatory cell infiltration, and lysosomal activation
- Certain risk factors like smoking and hyperlipidemia may act as accelerating agents. 

4. Thyroid abnormalities (thyrotoxic cardiomyopathy)
- Altered myocyte energy production, intracellular metabolism, and myofibril contractile function.
- Left ventricular hypertrophy
- Heart rhythm disturbances
- Primary atrial fibrillation
- Dilation of the heart chambers

Diastolic dysfunction (Filling dysfunction)
- Impaired ventricular filling
- may be due to impaired relaxation (e.g In hypertrophy)
- may be due to Increased stiffness (e.g in Sarcoidosis)
- Less common compared to systolic dysfunction

Causes of Diastolic dysfunction
- Myocardial Hypertrophy (Failure of LV to relax properly in Atrial systole)
- Valvular diseases (eg In Mitral Stenosis)
- Restrictive cardiomyopathy
i. Amyloidosis
ii. Sarcoidosis
iii. Hemochromatosis

High Output Cardiac failure
- An increase in CO is needed for the requirements of peripheral tissues for oxygen
- Abnormaly increased requirement of Oxygen by peripheral tissues

Causes of High Output Cardiac Failure (Mitral TAP TAAP)
1. Miral Regurgitation
2. Thymine deficiency (Wet Ber1 Ber1)
3. Anemia (Chronic)
4. Pregnancy
5. Thyroid abnormal high (Hyperthyroidism)
6. AV shunts
7. Aortic insufficiency
8. Paget disease of bone

Symptoms of Left Heart Failure
- Mostly due to High pressure transmitted to the Lungs and reduced Cardiac output

1) Dyspnea
- Due to Pulmonary Edema – Blood spilling into the Alveoli

2) Orthopnea
– Difficulty breathing in recumbent position due to increased preload
- Since veins are not flowing against gravity

3) Paroxysmal Nocturnal Dyspnea
- Awakening after 1-2 hrs of sleep due to acute shortness of breath

4) Nocturnal cough

5) Confusion and Memory Impair
- Due to reduced blood supply to Brain
- Common in advanced disease

6) Diaphoresis and Cold extremities
- The sympathetic system is activated due to reduced blood flow reaching organs (especially kidneys)
- Due to Constriction of peripheral vessels to shunt blood to the internal organs - - - -- Diaphoresis (Stimulated by Sympathetics) Sympathetics also cause sweating

- Occurs in worsening CHF

Signs of Left sided CHF
- The Signs confirm/explain the symptoms of the patients

1) Displaced Apex beat (Point of Maximum Impulse)
- In Adults normal apex beat is palpated in the precordium left 5th intercostal space, half inch medial to the left midclavicular line and 3-4 inches left of left border of sternum.
- In children the normal apex beat occurs in the fourth rib interspace medial to the nipple.
- It is displaced when it is palpated lateral to the normal, or when it is felt on a larger surface of the palm

2) Pathologic S3 (Rapid filling into non-compliant left ventricle e.g in hypertrophy)
- Increased filling pressure
- S3 = Heard at Ap3x with b3ll of stethoscope
- Sp3cific for CHF
- Normal in kids
- It is called a ventricular gallop
- S3 is Sp3cific

3)S4 gallop (atrial systole into Sti4ned ventricles)
- Due to ejection into Stiff (Sti44) ventricles
- Hear in either of 2 places depending on affected ventricle (Left or Right)
- If Stiff Left Ventricle = Apex with patient in left lateral decubitus position (Or on expiration/exercise)
- If stiff Right Ventricle = Left sternal border (louder with exercise and deep quick inspiration)

4) Crackles
- Due to Pulmonary edema
- They cause dyspnea
- Crackles are caused by the "popping open" of small airways and alveoli collapsed by fluid.
- They are often bibasal 

5)Dullness on Percussion/Decreased Fremitus
- Often in the lower lung fields
- Are usually due to pleural effusion
- Pleural effusions in CHF are due to elevated pulmonary capillary pressure.
- Pleural effusion in heart failure results from increased interstitial fluid in the lung 
- These Pleural effusion are usually bilateral > Unilateral and can be worse on the left > right
- These pleural effusions can be Transudates > Exudates

6)Increased intensity of Pulmonic component of second heart sound
- Due to pulmonary Hypertension

Symptoms/Signs of Right Heart Failure
- Due to increased pressure in the right heart transmitted to the veins
1. Pitting Peripheral Edema
- Usually unspecific finding
- can be due to other causes 

2. Jugular Venous Distention

3. Hepatomegaly

4. Hepatojugular reflux

5. Right Ventricular heave/Parasternal heave
- A parasternal heave (lift) is a precordial impulse that may be felt (palpated) in patients with cardiac or respiratory disease
- Parasternal heave can occur in the setting of right ventricular enlargement
- The right ventricle is most anterior (closest to the chest wall).
- In a normal right ventricle no impulse or a slight inward impulse is felt

6. Nocturia
- Often early in the course of heart failure.
- Recumbency reduces the deficit in cardiac output in relation to oxygen demand
- Pooling of blood in the lower extremities is reduced and heart isnt pumping against gravity
- Renal vasoconstriction diminishes, and urine formation increases.
- Prevents them from obtaining much-needed rest.

7. Ascitis
- Due to increased pressure gradient in the portal vein
- Nausea
- Bloating
- Abdominal pain
- Loss of appetite

Tests to order in Congestive Heart Failure
- To find the causes of Heart Failure
- To explain the symptoms of Heart Failure
- To detect worsening Heart Failure

Chest X-ray
- Detects
i. Pulmonary Edema (Pulmonary Edema cause dyspnea)
ii. Cardiomegaly (Cardiomegaly may be the cause of CHF)
iii. Rules out COPD (A differential for dyspnea)

ECG
- Detects cause of CHF

Cardiac Enzymes
- Rules out MI as cause

CBC
- Rules out Anemia (Chronic Anemia is a cause of High output Cardiac failure)

Echocardiogram
- Estimate EF (Diastolic/systolic dysfnx)
- rule out pericardial effusion

Radionuclide Ventriculography using technetium

Catheterization
- Rules out CAD as cause of CHF

Stress Testing

Chest X-Ray in CHF 

1. Cardiomegaly

2. Kerley B lines
- These are short parallel lines (thin linear pulmonary opacities) at the lung periphery.
- Often due to interstitial pulmonary edema (fluid or cellular infiltration into the interstitium of the lungs) 
- Often at the lung bases near the costophrenic angles on the PA radioaph
- Mostly at the substernal region on lateral radiographs

3. Increased Interstitial markings
- As a result of the increased pressure in the capillaries = increased fluids in interstitium
- leakage of fluid into the interstitium (interlobular and peribronchial) and the pleural space and finally into the alveoli resulting in pulmonary edema.
- Fluid in the peripheral interlobular septa is seen as Kerley B or septal lines.

4. Pleural effusion
- Leakage of fluids into the pleural space
- Pleural effusion is bilateral in 70% of cases of CHF.
- When unilateral, it is slightly more often on the right side than on the left side.

Echocardiogram
- Transthoracic
1. Initial Test of choice
2. Determines if Systolic or Diastolic dysfunction predominates
3. Determines cause
4. Estimates EF(< or > 40%)
5. Shows Chambers (Dilatation/Hypertrophy)

ECG
- Usually Non-Specific
- helps determine cause of CHF
i. Chamber enlargement
ii. Ischemic Heart Disease

Radionuclide ventriculography using technetium-99m
- Called MUltiGated Acquisition (MUGA) scan
- Uses Technetium-99m(99mTc) as radioactive material
- A gamma camera is used to create an image following injection of 99mTc labeled red blood cells.
- The Radionuclide has the property of circulating through the cardiac chambers. 
- In perfusion imaging, radionuclide is taken up by the myocardial cells, making its presence correlate with myocardial perfusion or viability of the cells.
- Evaluates CAD, cardiomyopathy, Valvular and Congenital Heart diseases.
- Radioactive material is retained in the patient for several days (may trigger security alarms)
- Gives a much more precise measurement of left ventricular ejection fraction 
- Used in monitoring cardiac function in chemotherapy

Cardiac catheterization
- Gives quantitative info of diastolic and systolic dysfunction
- Clarify cause of CHF
- Consider coronary angiography to exclude CAD as cause

Stress testing
- Detects ischemia
- Detects level of Myocardial conditioning 
- Differentiates etiology of dyspnea (COPD and Cardiac origin)
- Dynamic response of HR, rhythm and BP

B-type Natriuretic Peptide (BNP)
- Released from ventricles
- Released in response to ventricular volume expansion and pressure overload
- > 150pg/mL correlates with decompensated CHF
- useful in differentiating dyspnea (CHF and COPD)
NT-proBNP
- newer assay
- normal range depends on age of patient
- 40 days post MI
ii. EF < 35%
iii. Symptomatic Class 3 or 4 despite adequate therapy

Cardiac Resynchronization Therapy (CRT)
- Biventricular pacemaker
- Indicated for patients who have indications for ICD + Prolonged QRS duration (> 120msec)
- Most patients receive a combined device (ICD and CRT)

Cardiac transplantation
- Last alternative after all treatment modality have failed

Diastolic dysfunction treatmet
- Treatment is symptomatic
- B-blocker
- Diuretics 
- ACEI (Unclear benefits)
- ARBs (Unclear benefits)

Contraindicated in Diastolic dysfunction
- Digoxin
- Spironolactone

General Contraindications in CHF
1. Thiazolidinediones
2. Anti-Arrhythmics
3. Metformin
4. NSAIDS

Thiazolidinediones (Rosiglitazone, Pioglitazone)
- Also known as glitazones
- A group of oral Hypoglycemic drugs for DM2
- Works on the Fats and Muscles to reduce Insulin resistance
- May cause Hepatotoxicity 
- Act on renal peroxisome proliferator-activated receptor gamma (PPAR-y) to increased sodium retention. 

Anti-Arrhythmics (Only B-blockers shows clear benefit with less side effects)
- Amiodarone is a great choice for arrhythmias in CHF, but it is highly toxic to other systems (esp. lungs)
- Most others are -ve inotropes and are proarrhythmics (Ironically) 

Pain killers (NSAIDS)
- COX-1 and COX-2 inhibitors
- Inhibits prostalgladins (vasodilators)
- Impair renal function in patients with a decreased effective circulating volume
- Leads to H20 and Na+ retention 

Calcium Channel Blockers
- They have no role in CHF
- They may increase mortality (increase hrt rate)
- Amlodippine and Felodipine are safe in CHF (Use only when indicated)

Acute Decompensated Heart Failure
- Refers to ACute Dyspnea + elevated left sided filling pressure
- mostly due to Sys or dia dysfnx
- Flash pulmonary edema

Diagnosis
- ECG
- CXR
- ABG
- B-type Natriuretic peptide (BNP)
- Echo
- Coronary angiogram iif indicated

Management
- Hospital Admission
- Oxygenation and Ventilatory assist (Non rebreather, NPPV, intubation)
- Diuretics (really important for symptoms)
- Na+ restriction
- Nitrates (For thsoe without hypotension)
- Acute inotrope (Dobutamine) for refracory P edema despite tx (digoxin takes weeks to work)

Limited evidence for use
- Moprhine sulfate

Determine effectiveness and response to treatment (Diuresis) by taking daily weigth of pt

Differentials of Acute Decompensated CHF

Other diseases causing rapid respiratory distress
- P. Embolism
- Asthma
- Pneumonia