Heart%20failure%20-%20chronic Diagnosis

• Requires a thorough history and physical examination, identification of the etiology and risk factors, and diagnostic examination of the cardiac structure and function in order to identify diseases that will require specific management

Development Stages of Heart Failure

Stage A

• At risk for HF but without structural or functional heart disease or signs or symptoms of HF
  • Abnormal cardiac biomarkers are absent
  • Hypertension, atherosclerotic cardiovascular (CV) disease, diabetes, obesity, metabolic syndrome
  • Use of cardiotoxins
  • Family history of or genetic variant for cardiomyopathy

Stage B

• Structural or functional heart disease but without signs or symptoms of HF
  
  • Previous myocardial infarction (MI), left ventricular (LV) remodelling including left ventricular hypertrophy (LVH) and low ejection fraction (EF), asymptomatic valvular disease
  • Elevated levels of natriuretic peptide or cardiac troponin in the setting of cardiotoxin exposure

Stage C

• Structural and/or functional heart disease with prior or current signs and/or symptoms of HF
  
  • Persistent HF or HF in remission
  • Shortness of breath (SOB), fatigue and decreased exercise tolerance

Stage D

• Refractory, advanced or end-stage HF
  
  • Marked signs and/or symptoms at rest despite guideline-directed medical treatment (GDMT) (refractory or intolerant to GDMT), recurrent hospitalizations
  • Requires specialized treatment interventions

Framingham Diagnostic Criteria for Heart Failure

• HF is diagnosed with ≥2 major criteria or 1 major criterion with 2 minor criteria:
  • Major criteria: Jugular venous distension, orthopnea, rales, acute pulmonary edema, cardiomegaly, S3 gallop rhythm, hepatojugular reflux
  • Minor criteria: Nocturnal cough, dyspnea on exertion, pleural effusion, heart rate >120 beats per minute (bpm), hepatomegaly, ankle edema

H₂FPEF Score 

• Due to the lack of testing to definitively diagnose HFpEF, a diagnostic scoring system may be utilized to help in the evaluation of patients with suspected HFpEF
• A score of ≥6 points is highly diagnostic of HFpEF:
  • Heavy (body mass index [BMI] >30 kg/m²) (2 points), Hypertension (on ≥2 antihypertensive medications) (1 point), atrial Fibrillation (3 points), Pulmonary hypertension (pulmonary artery systolic pressure >35 mmHg on Doppler echocardiography) (1 point), Elder (>60 years old) (1 point), Filling pressures (E/e’ >9 on Doppler echocardiography) (1 point)

Types of Heart Failure

Heart Failure Based on Time-course

• Acute heart failure (AHF)
  • Refers to the first occurrence (new-onset or de novo) of HF 
  • May result from the deterioration of a previously stable HF
• Chronic heart failure (CHF)
  • A chronic state where patient’s signs and symptoms have been unchanged (stable) for at least a month  
  • May decompensate suddenly or slowly when stable CHF deteriorates leading to hospitalization or outpatient IV diuretic therapy
• Congestive HF
  • Refers to AHF or CHF that has evidence of volume overload
• Transient HF 
  • Refers to symptomatic HF over a limited period of time, although long-term therapy may be indicated
  • Recurrent or episodic

Heart Failure Based on Left Ventricular Ejection Fraction (LVEF)

• HF with preserved EF (HFpEF) (diastolic HF)
  • With preserved systolic function; EF is defined as ≥50%
  • Condition is not due to hypertrophic or infiltrative cardiomyopathy, high-output HF, or pericardial or valvular disease
• HF with reduced EF (HFrEF) (systolic HF)
  • EF is defined as ≤40%
• Patients with an EF in the 41-49% range represent a ‘grey area’ and it is termed HF with mildly reduced EF (HFmrEF)
• Further criteria for the diagnosis of HF with preserved and mildly reduced EF include presence of HF symptoms and/or signs, elevated levels of natriuretic peptides with at least 1 added criterion of either significant structural heart disease or diastolic dysfunction
• HF with improved EF (HFimpEF)
  • With history of HFrEF or baseline LVEF ≤40%, whose EF has increased by ≥10% to >40%

Chronic Heart Failure Classification Based on Duration Since Last Admission

• Help optimize GDMT

C1: Optimization Phase

• Recently diagnosed HF and not on optimal GDMT

C2: Remission Phase

• No hospitalization for HF for >6 months and patient is with optimal medical therapy

C3: Vulnerable Phase

• With recent hospitalization within 6 months but not within 30 days

C4: Transition Phase

• Recent hospitalization within 30 days

• Determine predisposition to risk factors especially in lifestyle (eg smoking, diet, alcohol consumption, substance abuse and inactivity)
• Review the past medical history
  
  • To identify possible cause of HF and presence of comorbid illnesses (eg history of CAD or arterial hypertension, previous cardiac surgery, chronic lung, liver or kidney disease, COVID-19 infection)
    • Screening HF patients for CV and non-CV comorbidities help alleviate symptoms and improve prognosis 
  • Current or past standard or alternative therapies and chemotherapy (eg diuretic use, exposure to radiation or cardiotoxic drug)
• Family history to determine familial predisposition to atherosclerotic disease, cardiomyopathy (obtain a 3-generation family history), conduction system disease or tachyarrhythmias

Assessment of Volume Status

• Determines the need for diuretic treatment
• Detects sodium excess or deficiency that may affect efficacy and reduce tolerability of drugs used to treat HF
• At each visit, record the patient’s weight, vital signs especially blood pressure (BP) (sitting and standing) and other abnormal physical findings including presence of clinical congestion

Assessment of Functional Capacity

New York Heart Association (NYHA) Functional Classification in Patients with Heart Failure

• Class I
  
  • Patient has no limitation of physical activity
  • Ordinary physical activity does not cause HF symptoms (eg palpitation, dyspnea or fatigue)

• Class II
  
  • Patient has slight limitation of physical activity
  • Comfortable at rest but ordinary physical activity produces HF symptoms

• Class III
  
  • Patient has a marked limitation of physical activity
  • Comfortable at rest but less than ordinary activity causes HF symptoms

• Class IV
  
  • The patient is unable to carry out any physical activity without discomfort
  • HF symptoms are present at rest and any physical activity will cause an increase in discomfort

• Lab testing will confirm the presence of HF and may show the presence of disorders that can lead to or exacerbate HF and may help guide appropriate management
• Patients with HFpEF are recommended to have screening for and treatment of etiologies and CV and non-CV comorbidities 
• For the diagnosis of HFpEF and HFmrEF, spontaneous or provokable increased LV filling pressures should be confirmed in patients with LVEF >40% via elevated levels of natriuretic peptides, diastolic function on echocardiography or invasive hemodynamic measurement 
  • Additional findings supporting an HFpEF diagnosis include an increase in the LV mass index and/or left atrial volume index

Tests to Consider in All Patients

• Initial evaluation includes, but is not limited to, the following:
  
  • Complete blood count (CBC), serum electrolytes (include sodium, potassium, calcium and magnesium), blood urea nitrogen (BUN), creatinine/estimated glomerular filtration rate (eGFR), albumin, cardiac enzymes, liver enzymes, bilirubin, serum ferritin, transferrin saturation (TSAT), total iron-binding capacity (TIBC), blood lipids, blood glucose, international normalized ratio (INR), C-reactive protein (CRP), thyroid function and urinalysis
    • Used to detect reversible/treatable causes of HF and comorbidities interfering with HF 
  • Natriuretic peptides (B-type natriuretic peptide [BNP], N-terminal pro B-type natriuretic peptide [NT-proBNP] or mid-regional atrial natriuretic peptide [MR-proANP])
    • Elevated levels: Ambulatory: BNP ≥35 pg/mL or NT-proBNP ≥125 pg/mL; hospitalized: BNP ≥100 pg/mL or NT-proBNP ≥300 pg/mL
    • Useful for differentiating dyspnea caused by HF from dyspnea due to other causes
    • Used in patients in whom the diagnosis of HF is uncertain and when an echocardiogram cannot be performed
    • Also helpful in establishing disease severity, stratifying risk and obtaining prognostic information
    • Recommended biomarker to be used to screen high-risk patients for HF

• 12-Lead electrocardiogram (ECG)
  
  • Most common findings are nonspecific repolarization abnormalities (ST-T wave changes)
  • Abnormalities are usually nonspecific (include LV hypertrophy, Q wave, sinus tachycardia and atrial fibrillation [AF])
  • Conduction abnormalities may also be seen (eg left bundle branch block, first-degree atrioventricular block, left anterior hemiblock and nonspecific intraventricular conduction delays)
  • Information obtained can assist in treatment planning and is of prognostic importance
  • Normal ECG makes the diagnosis of HF due to LV systolic dysfunction less likely

• Chest radiography (X-ray)
  
  • Useful to determine the heart size, presence of pulmonary congestion, detection of pulmonary and other diseases and proper placement of implanted cardiac device
  • Normal chest X-ray does not exclude the diagnosis of HF
  • Common abnormal findings are pulmonary venous redistribution with upper lobe blood diversion

• Transthoracic echocardiography
  
  • Most useful initial investigation performed immediately to confirm the diagnosis in patients suspected with HF
  • Evaluates cardiac structure and function (eg chamber volumes/sizes, LV systolic function by LVEF, diastolic function, hemodynamics, wall thickness and valvular structure and function), assists in treatment management and obtains prognostic information
    • Women with HFpEF have more significant concentric LV remodeling and more impaired diastolic relaxation compared with men with HFpEF 
  • Excludes correctable causes of HF

Tests to Consider in Selected Patients

• Cardiac magnetic resonance imaging (CMRI)
  
  • Performed in select patients, it evaluates cardiac structure and function, measures LVEF, assesses myocardial scarring, characterizes cardiac tissue especially in patients with inadequate echocardiographic images or where there are inconclusive or incomplete echocardiographic findings
  • Useful in the work-up of patients suspected with cardiomyopathy, arrhythmias, cardiac tumors or cardiac involvement by a tumor, pericardial disease, myocarditis, cardiac sarcoidosis and complex congenital heart disease

• Coronary angiography
  
  • Recommended in patients with angina pectoris despite medical therapy or symptomatic ventricular arrhythmias who are suitable for coronary revascularization to evaluate the coronary anatomy (ie establishes the presence and extent of CAD)
  • Also considered in patients with evidence of reversible myocardial ischemia on non-invasive testing, especially if the EF is decreased
  • A multidetector computed tomography (MDCT) study may be used as an alternative to invasive coronary angiography in select patients to rule out significant CAD

• Cardiac catheterization
  
  • Considered in patients who are being evaluated for heart transplantation or mechanical circulatory support
  • Evaluates the cardiac function and pulmonary arterial resistance
  • May be performed in cases of uncertain diagnosis, eg early HFpEF
  • A right heart catheterization should be considered in patients in whom HF is thought to be caused by congenital heart disease, constrictive pericarditis, restrictive cardiomyopathy and high output states 
    • May be considered to determine patient’s volume status

• Myocardial perfusion/ischemia imaging (eg stress echocardiography, CMRI, single photon emission computed tomography [SPECT] or positron emission tomography [PET])
  
  • Alternative imaging modality in patients with unsatisfactory echocardiographic findings or when the degree of LVEF influences treatment management
  • Considered in patients who are suspected to have CAD and who are suitable for coronary revascularization

• Cardiopulmonary exercise testing
  
  • Detects reversible myocardial ischemia and investigates the cause of dyspnea 
  • Used in the objective evaluation of exercise and functional capacity and exertional symptoms to aid in prescribing an exercise training program
  • Also used for evaluating patients for heart transplantation and/or mechanical circulatory support and to obtain prognostic information
  • An alternative option to measure patient’s exercise capacity is the 6-minute walk test

• Endomyocardial biopsy
  
  • May be useful in identifying a specific diagnosis which would influence treatment decisions 
  • May be indicated rarely in patients with dilated cardiomyopathy with recent onset of symptoms and where HF has been excluded by angiography and in primary myocardial diseases like endomyocardial fibrosis and amyloid heart disease
  • May also be used in patients with rapidly progressive clinical HF or ventricular dysfunction despite appropriate medical treatment and those who are suspected of having myocarditis or infiltrative diseases (eg amyloidosis)

• Spirometry and pulmonary function test
  
  • Assess the potential contribution of lung disease to the patient’s dyspnea
  • Demonstrate or exclude concomitant smoking-related or other respiratory causes of airway limitation