Understanding Heart Failure

• Heart failure is a clinical syndrome caused by structural or functional cardiac abnormalities, elevated natriuretic peptide levels, and/or pulmonary or systemic congestion.

High-Output States

• Metabolic and nutritional disorders, thyrotoxicosis, excessive blood flow needs, arteriovenous shunting, and chronic anemia lead to high-output states.
• High-output states increase strain on the heart, which can lead to heart failure if underlying structural heart disease is present.

Paradigms of Heart Failure

• Classification includes functional class (NYHA I-IV) and physiological stage (ACC/AHA A-D); side can be RV, LV, or Biventricular.
• Types of heart failure include HF with preserved ejection fraction (diastolic dysfunction), HF with diminished ejection fraction (systolic dysfunction), and mixed systolic/diastolic.
• Heart failure can be categorized by duration as new onset, chronic, or acute decompensation (ADHF).

NYHA Functional Classification

• Class 1 defined as asymptomatic.
• Class 2 is defined as having symptoms with moderate activity (e.g., long-distance walking, climbing two flights of stairs).
• Class 3 includes symptoms with minimal exertion (e.g., short-distance walking, climbing one flight of stairs).
• Class 4 means symptoms are present at rest.

ACC/AHA Heart Failure Stages

• Stage A involves being at high risk but asymptomatic, such as hypertension, diabetes mellitus, CAD, or family history of cardiomyopathy.
• Stage B is defined as pre-heart failure and asymptomatic, such as previous MI, LV dysfunction, or valvular heart disease.
• Stage C is symptomatic heart failure with structural heart disease, dyspnea, fatigue, and impaired exercise tolerance.
• Stage D involves advanced heart failure with marked symptoms that endure even with maximal medical therapy.

RV Failure

• Causes of RV failure include left ventricular failure, coronary artery disease (ischemia), pulmonary hypertension, right valvular disease and embolism, chronic pulmonary disease, and neuromuscular disease.
• Elevated JVP and edema are symptoms of pure right ventricle failure.
• Right heart failure includes increased central venous pressure, increased resistance to portal flow, hepatomegaly, ankle and sacral edema, ascites, and elevated jugular venous pressure.

LV Failure

• Coronary artery disease (ischemia) and left valvular disease are important causes of left ventricular failure.
• Dyspnea on exertion (DOE), paroxysmal nocturnal dyspnea (PND), orthopnea, dyspnea at rest, and pulmonary edema are symptoms of left ventricle failure.

Congestive Heart Failure (CHF)

• Decreased LV output with exercise leads to dyspnea on exertion.
• Increased end diastolic volume leads to cardiac dilation.
• LV failure leads to increased pulmonary venous pressure and fluid transudation, resulting in pulmonary edema and paroxysmal nocturnal dyspnea.
• Increased venous return exacerbates pulmonary vascular congestion, leading to orthopnea.

Reality of Heart Failure

• Low output heart failure is a mix of right and left heart failure, resulting in patients having symptoms of both.
• Left heart failure is the most common cause of right heart failure.
• Decreased exercise tolerance and fluid retention may indicate heart failure

Physical Exam Signs

• Pulmonary crackles, wheezing (cardiac wheezes) in Lungs may indicate Heart Failure.
• An S3 heart sound in left ventricular failure (systolic dysfunction) is a sign
• S4 heart sounds in decreased LV compliance (diastolic dysfunction) may be present
• Acute pulmonary edema, cyanosis, hypotension, and poor cerebral and renal perfusion are signs.

CXR Findings

• Cardiomegaly, vascular redistribution (flow to apices), pulmonary venous congestion, Kerley B lines, and pleural effusions are CXR findings. -Kerley B lines reflect chronic elevation of LA pressure and thickening of intralobular septa from edema

BNP

• B-Type Natriuretic Peptide/Brain Natriuretic Peptide (BNP) is synthesized and released by the heart.
• Reduced LVEF, LV hypertrophy, elevated LV filling pressures, and acute MI and ischemia are associated with elevated BNP levels.
• BNP is used to differentiate dyspnea from HF from other causes in combination with clinical evaluation.
• A BNP level < 50 pg/ml has a negative predictive value of 96%.
• A BNP level > 500 pg/ml is predictive of CHF.
• BNP levels of 100-500 pg/ml may mean CHF, pulmonary embolus, primary pulmonary hypertension, chronic pulmonary disease, end-stage renal disease, cirrhosis, or hormone replacement.

Echocardiogram

• Evaluation of ejection fraction is required
• Can find Structural abnormalities of the left ventricle, abnormalities of the myocardium or pericardium, and valvular heart disease

Physical Exam Findings

• Normal patients have normal general appearance (WDWN), flat neck veins, clear lungs, and normal cardiovascular/abdominal/extremity exams.
• Decompensated HF patients can have labored breathing, elevated JVP, bibasilar rales, tachycardia, bulging flanks, shifting dullness, fluid wave, and lower extremity edema.

Heart Failure Work-Up

• Obtain a thorough history and physical exam.
• Perform lab tests.
• Conduct a 12 lead ECG and CXR.
• Perform an echocardiogram to evaluate LVEF, left ventricular size, wall thickness, and valve function.
• Look for the etiology, such as ischemia, valvular heart disease, HTN, cardiomyopathies, or toxins.

EF values

• Ejection Fraction (EF) = (SV / EDV) × 100%, where stroke volume (SV) = EDV – ESV.
• Normal ejection fraction is >50-60%.

Pathophysiologic Classification

• HF with preserved EF (HFpEF) LVEF is at least 50%
• HF with mildly reduced EF (HFmrEF) LVEF between 41-49%
• HF with reduced EF (HFrEF) LVEF of up to 40%
• HF with improved EF (HFimpEF) baseline LVEF of 40% or less, an increase of at least 10 points from baseline, with second measurement LVEF greater than 40%.
• HF with preserved Ejection Fraction (formerly known as Diastolic Dysfunction)
• HF with diminished Ejection Fraction (formerly known as Systolic Dysfunction); may have mixed systolic/diastolic issues

HFpEF

• HFpEF means HF with preserved Ejection Fraction (formerly known as Diastolic Dysfunction).
• HFpEF diagnosis involves clinical signs or symptoms of HF; evidence of preserved or normal LVEF; and evidence of abnormal LV diastolic dysfunction via Doppler echocardiography or cardiac catheterization.

Diastolic Dysfunction Etiologies

• Pathologic hypertrophy from secondary causes like hypertension or obstructive valvular disease (Aortic Stenosis).
• Can be caused by primary (hypertrophic cardiomyopathies) or restrictive cardiomyopathy.
• Can be caused by Infiltrative disorders (amyloidosis, sarcoidosis) or storage diseases (hemochromatosis).
• Additional causes include Fibrosis (from myocardial ischemia/infarction), aging, endomyocardial disorders, or metabolic disorder

Diastolic Dysfunction Pathophysiology in HTN

• The LV hypertrophies in response to hypertension and increased afterload.
• Concentric hypertrophy, directed inwardly, encroaches on the LV cavity (cLVH).
• Stiff, fibrotic LV muscle cannot relax in diastole and does not fill enough, resulting in reduced end diastolic volume.
• The ejection fraction will be preserved, but can be normal.

Restrictive Cardiomyopathy Etiologies

• Amyloidosis is a cause via overproduction of a protein, with primary/genetic causes or secondary (multiple myeloma); deposits insoluble proteins as fibrils in the heart, resulting in HF
• In an echocardiogram, it appears with a “speckled pattern" and apple green birefringence with congo red staining in cardiac biopsies
• Sarcoidosis - non-caseating granulomas that may infiltrate the myocardium.
• Hemochromatosis is also a cause and also known as "bronze diabetes" and iron overload, deposition may involve the heart.

Restrictive Cardiomyopathy

• Cardiac Biopsy may be useful for diagnosis
• Differentiate what type of restrictive cardiomyopathy from constrictive pericarditis, which is surgically correctable
• Treatment is focused on underlying etiology:
• Amyloidosis treat with tafamidis (Vyndamax), recently FDA approved to improve functional decline
• Sarcoidosis treat with Corticosteroids or other immunosuppressants
• Hemochromatosis treat with Therapeutic phlebotomy

Hypertrophic Cardiomyopathies

• Etiologies may be congenital or familial.
• Hypertrophy of IVS results in decreased LV outflow (with or without obstruction), systolic function is normal but increased LV stiffness results in elevated diastolic filling pressures.
• Considered the prototype of diastolic dysfunction.

Hypertrophic Cardiomyopathy Symptoms

• Dyspnea, chest pain and Syncope (post-exertional).
• Common ventricular arrhythmias may cause sudden cardiac death, especially in athletes after extreme exertion.

Hypertrophic Cardiomyopathy PE Findings

• Brisk carotid upstroke with pulsus bisferiens and Loud S4
• Loud systolic murmur at the left sternal border
• Increases with valsalva or standing abruptly, and decreases with squatting and handgrip

Hypertrophic Cardiomyopathy Evaluation

• Echocardiogram shows Asymmetrical Septal Hypertrophy Septum > 1.3 x the thickness of LV posterior wall
• LV has excellent contractile function with small end -systolic volume.
• Systolic Anterior Motion of the Mitral Valve

Hypertrophic Cardiomyopathy Treatment

• Beta blockers are first line followed by Verapamil second line; caution because of hypotension
• Antiarrhythmic agents, especially amiodarone, may suppress atrial & ventricular arrhythmias
• Sudden Cardiac Death primary or secondary prevention with Implantable Cardioverter defibrillator (ICD) in select patients
• Digoxin/other inotropes, overdiuresis, and vasodilators are contraindicated

Hypertrophic Cardiomyopathy additional interventions

• A surgical myomectomy may used for patients who are refractory to medical treatment
• Alcohol Septal Ablation may used for patients who are refractory to medical treatment

Hypertrophic Cardiomyopathy Caution

• Prolonged exercise and heavy lifting/extreme physical exertion are be avoided

Best DX Test for HF w/ preserved EF

• Echocardiogram DX will show preserved Contractility and ejection fraction is usually normal, but will have Concentric hypertrophy on echo, Inwardly directed ventricular hypertrophy

General Treatment for HFpEF

• The main goal is to to Manage volume overload using diuretics
• Treat Blood Pressure with guideline-directed medical therapy such as ACE-I or ARB, and attain SBP <130 mm Hg in patients with HFpEF and persistent hypertension after management of volume overload
• Use aldosterone antagonists in appropriately selected patients with HFpEF
• Promote Exercise training for quality of life and exercise capacity
• Use Empagliflozin to reduce the risk of cardiovascular death and hospitalization for heart failure in adults with HF independent of LVEF.
• Using Digoxin has NO ROLE in the treatment of HFpEF

Specific Treatments

• Treat Restrictive Cardiomyopathies using: Amyloidosis – tafamidis (Vyndamax), Sarcoidosis - Corticosteroids or other immunosuppressants, or Hemochromatosis using Therapeutic phlebotomy

Treatments that avoid specific indications

• Hypertrophic Cardiomyopathies - Beta blockers first line or Verapamil second line
• Surgical myomectomy or alcohol septal ablation if failed medical management.
• Sudden Cardiac Death primary or secondary prevention with Implantable Cardioverter defibrillator (ICD) in select patients
• Contraindicated: Digoxin/other inotropes, overdiuresis, vasodilators & extreme physical exertion