Chronic heart failure
From IDWiki
Background
Definition
- A syndrome of volume overload and poor tissue perfusion that is caused by cardiac dysfunction and is characterized by dyspnea, fatigue, and edema
- Two broad types:
- Heart failure with reduced ejection fraction <40% (HFrEF or systolic dysfunction)
- Heart failure with preserved ejection fraction (HFpEF or diastolic dysfunction)
Stages
- Stage A: no structural heart disease or symptoms but high risk for developing HF (e.g., patients with diabetes mellitus or hypertension)
- Stage B: structural heart disease without symptoms of HF (e.g., patients with a previous MI and asymptomatic LV dysfunction)
- Stage C: structural heart disease with symptoms of HF (e.g., patients with a previous MI with dyspnea and fatigue)
- Stage D: refractory HF requiring special interventions (e.g., patients with refractory HF who are awaiting cardiac transplantation).
Etiologies
By Subtype
- HFrEF
- Coronary artery disease (most common)
- Hypertension (most common)
- Viral infection
- Chronic alcohol use
- Valvular heart disease
- Chemotherapy, such as doxorubicin or trastuzumab
- Peripartum cardiomyopathy
- Idiopathic dilated cardiomyopathy
- Genetic causes of cardiomyopathy
- HFpEF
- Hypertension (most common)
- Myocardial infarction
By Cardiomyopathy
- Dilated cardiomyopathy: toxins (alcohol, cocaine, chemotherapy), myocarditis, Chagas disease, peripartum cardiopmyopathy, familial cardiomyopathies
- Hypertrophic cardiomyopathy: hypertension
- Restrictive cardiomyopathy
- Arrhythmogenic right ventricular cardiomyopathy
- Unclassified cardiomyopathy: Takotsubo cardiomyopathy, non-compaction cardiomyopathy
By Risk Factor
- Common
- Tachyarrhythmia
- Valvular disease
- If CAD risk factors:
- Coronary artery disease
- Hypertensive cardiomyopathy
- Other risks
- Toxic agents: alcohol, amphetamines, cocaine, steroids, chemotherapy, heavy metals, radiation
- Pregnancy: PPCM, pre-eclampsia, gestational diabetes
- Inflammatory or infectious: myocarditis, sarcoidosis, infectious hypereosinophilia, giant celll lymphocytic, auto-immune diseases
- Metabolic: diabetes, thyroid disease, adrenal insufficiency, pheochromocytoma, Cushing disease
- Nutritional: thiamine deficiency, selenium deficiency, malnutrition, obesity
- Infiltrative: amyloidosis, glycogen storage disease, Fabry disease
- Hereditary: hypertrophic cardiomyopathy, ARVC, LV noncompaction, hemochromatosis
- Acute respiratory distress syndrome (ARDS)
Epidemiology
- 6-10% of people over age 65
Risk Factors
- Previous episode of acute heart failure
- Prior atrial fibrillation or coronary artery bypass surgery
- Myocardial infarction
- Coronary artery disease
- Diabetes mellitus
- Hypertension
Clinical Manifestations
History
- Hx of heart failure, MI, or CAD
- Dyspnea on exertion
- Paroxysmal nocturnal dyspnea
- Orthopnea
- Fatigue
- Determine NYHA classification of functional status
Signs & Symptoms
- Cardiac exam: S3 present, abdominojugular reflux, elevated JVP
- Respiratory exam: crackles/rales
- Lower extremity edema
| Dry | Wet | |
|---|---|---|
| Warm | Less congested Better-perfused |
More congested Better-perfused |
| Cold | Less congested Poorly perfused |
Less congested Poorly perfused |
Investigations
- Lab
- Troponins
- Natriuretic peptide (if diagnosis uncertain)
- NT-proBNP > 450 pg/mL if age < 50 years and > 900 pg/mL if age > 50 years; <100 pg/mL helps rule it out
- Imaging
- Chest X-ray showing pulmonary venous or interstitial edema, cardiomegaly, or pleural effusions
- Other
- EKG showing new atrial fibrillation, ischemic changes, or any other abnormality
- Echocardiography
- Systolic heart failure
- Reduced LV ejection fraction (LVEF)
- Diastolic heart failure
- E/A ratio less than 1
- MV deceleration time > 220ms
- Systolic heart failure
Management
- See also Acute heart failure management
Non-Pharmacologic Management
- Consider referral to multidisciplinary outpatient clinic
- Diet
- No-added-salt diet (2-3 g/day); 1-2g/day if severe fluid retention
- Fluid limited to 1.5 L/day to 2 L/day from all sources, if diuretics fail
- Exercise: regular exercise 3-5 times a week for 30-45 min per session (after stress test)
- Lifestyle
- Smoking cessation
- Decrease or eliminate alcohol intake
- Monitor body weight regularly for sudden increases (e.g. 2 kg increase in 3 days)
- Pneumococcal and annual influenza vaccines
- Avoid, when possible: NSAIDs (including COX-2 inhibitors), glucocorticoids, class I antiarrhythmics, sotalol and ibutilide,TCAs, dronedarone, verapamil and diltiazem (except in HFpEF), α-blockers, moxonidine, metformin, thiazolidinediones, anthracyclines
Manage Comorbidities
- Replace iron-deficiency with IV iron (improves quality of life)
- Avoid treating diabetes with glitazones, prefer SGLT-2 inhibitors
- Treat hypertension, especially in HFpEF
Pharmacologic Treatments
- Treat cardiovascular risk factors (hypertension, dyslipidemia, atherosclerotic disease)
- Previous MI: ASA 81mg po daily if indicated for secondary prevention
- Atrial fibrillation: warfarin or other anticoagulation
- Overall approach is triple therapy: ACEi, beta-blockers, aldosterone agonists
- Reassess NYHA class after maximizing treatment
- NYHA I: continue
- NYHA II-IV and sinus rhythm with HR ≥70: add ivabradine and switch ACEi to ARNI (Entresto)
- NYHA II-IV and sinus rhythm with HR < 70bpm or AF or pacemaker: switch ACEi to ARNI (Entresto)
- Reassess LVEF
- If NYHA I-III and LVEF ≤35%: consider ICD/CRT
- NYHA IV: consider hydralazine/nitrates, referral for mechanical support or transplant, refer to palliative care
- HFrEF:
- First-line: ACE inhibitor (second-line: ARB)
- First-line: beta-blocker (second-line: CCB)
- Titrate slowly, doubling dose q2-4 weeks
- Objective improvement may take 6-12 months
- If severe symptoms and LVEF<30%: aldosterone antagonist
- If African-American: consider adding ISDN
- If congestive symptoms:
- First-line: loop diuretic at lowest minimal dose required to control symptoms
- Second-line: consider adding thiazide or low-dose metolazone
- Last-line: consider adding digoxin if severe symptoms or poorly-controlled atrial fibrillation
- Monitor blood pressure while titrating up medication
Procedures
- Cardiac resynchronization therapy is indicated when LVEF<30%, LBBB, and QRS > 150ms
- Devices
- ICD if EF <35%
- CRT +/- ICD if reduced EF and LBBB
- Implantable hemodynamic monitor (CardioMEMS)
- Pulmonary artery pressure sensor
- Better than daily weights for predicting heart failure exacerbations
- Reduces hospitalizations by 30%
- Studied in HFpEF and HFrEF
- Expensive! $20k
- Surgery: see advanced therapies, below
Advanced Therapies
- Consider advanced therapies such as ventricular assist device or cardiac transplantation when heart failure is severe and refractory
- Possible indications include:
- LVEF <25%
- End-organ dysfunction
- Recurrent hospitalizations 2x/12months unexplained
- Unable to tolerate medical therapies, including hypotension
- Diuretic refractory
- Inotropic support
- Pulmonary hypertension and right heart failure
- Six-minute walk test <300m
- Increased 1yr mortality >20%
- Renal or hepatic dysfunction
- Chronic hyponatremia <134 chronically
- Cardiac cachexia
- Unable to tolerate ADLs
Prognosis
- 30-40% of patients die within 1 year of diagnosis and 60-70% die within 5 years
- NYHA II have a 5-10% annual mortality rate
- NYHA IV have a 30--70% annual mortality rate
- MAGGIC risk score
- Estimates 1 and 3 year survival
