JC09 (Medicine) - Exertional Heart Failure Flashcards
Define heart failure
HF:
Unable to pump blood at a rate to match requirement of metabolizing tissues
Due to forward failure (adequate filling pressure) or backward failure (congestion with high filling pressure to distend myocardium for higher CO)
S/S low cardiac output/ forward heart failure
S/S of right heart failure (backward HF)
S/S of left heart failure
Describe the Frank Starling Law
Mechanism of Orthopnea/ PND
Mechanism of pulmonary edema in left heart failure
Symptoms/ Signs of HF
- Which ones are the most specific/ sensitive?
Name two criteria for Dx of heart failure
Framingham criteria
Boston criteria
Name one criteria for severity of LV dysfunction
CXR Lung features of left heart failure
Upper lobe diversion/ Cephalization - pulmonary venous hypertension, pulmonary edema in the lower lobe compresses on lower lobe vessels and distends upper lobe vessels, exacerbated by hypoxia-vasoconstriction in lower lobe vessels
Kerley B lines (Septal lines) - Interstitial edema, develops at LA pressure > 15-20mmHg
Peribronchial cuffing - Interstitial fluid accumulate around bronchi causing thickening of bronchial wall, doughnut-like densities in parenchyma, LA pressure > 15-20mmHg
Biomarkers for heart failure
Levels for severities of HF
Physiological function of the marker
Brain Natriuretic Peptide (BNP) and NT-proBNP
Endogenous function: BNP from cardiomyocytes to resist fibrosis and myocardial hypertrophy by decreasing BP, sympathetic tone, RAAS activation
Cardiac causes of high BNP
Confounding/ Non-cardiac causes of high BNP
Surgical Treatment options for HF
Devices:
- Cardiac Resynchronization therapy (CRT) (biventricular pacing)
- Cardiac assist devices: Pacemaker
- Implantable Cardioverter Defibrillator (ICD)
Revascularization:
- Cardiac Transplant
- CABG for ischemic cardiomyopathy
- Valvular surgery
- Left ventricular assist device (LVAD)
Outline history taking questions for HF (apart from S/S)
Symptoms of HF: Characterize all symptoms in detail
Past history of CAD, PVD, Stroke
Etiologies:
- Risk factors of CVS: Smoking, Metabolic syndrome (HT, DM,HL)
- Valvular diseases: CTD, Rheumatic fever…etc
- Systemic diseases: Thyroid storm, Pheochromocytoma …etc
- Cardiotoxic drugs: Chemo/RT, Substance abuse
Family history:
- Sudden death at young age, FHx of myopathies, arrhythmias, premature CVD
First-line investigations for HF ***
Blood:
- CBC
- Serum K, Ca, PO4, glucose
- RFT, Serum Urea and Cr
- TSH, fT4
- BNP, Pro-BNP
Urine microscopy and urinalysis
CXR: Features of HF
ECG
Further confirmation: CT/ MRI, Nuclear scans e.g. MIBG, Exercise/ pharmacological stress testing, Cardiac catherization
Outline the NYHA Functional Classification to stage HF
Outline the clinical course of HF over time
Causes of HF
Myocardial disorders that cause HF
Classes of HF according to ejection fraction
Heart failure with Reduced Ejection Fraction (HFrEF)/ Systolic HF - LVEF <40%
Heart failure with Preserved Ejection Fraction (HFpEF)/ Diastolic HF - LVEF >50%
Other classes: HFmrEF (41-49%), HFpEF (>40%)
Compare HFrEF and HFpEF
- Demographics
- Risk factors
- Difference in CXR
Approach to Dx heart failure
- Clinical diagnosis by S/S and diagnostic criteria
- Unclear clinical diagnosis >> use BNP or Pro-BNP concentration with clinical context to Dx
Causes of acute HF
Respiratory causes:
- Acute respiratory failure
- Pulmonary embolism
Circulation emergency:
- Cardiogenic shock
- Hypertension emergency/ Malignant hypertension
Cardiac causes:
- Acute Coronary syndrome/ MI
- Arrhythmia
- Acute mechanical cause e.g. VHD, LVOTO
Systemic:
- Anemia
- Endocrine: e.g. thyroid storm, pheochromocytoma
- Adverse drug effects
Approach to treat hemodynamic profiles of heart failure *
Congestion (both left or right heart) (Yes or No) >> S3, peripheral edema, orthopnea and PND, high JVP, Pulmonary edema
Perfusion (Adequate or poor) >> low peripheral temp and pulse
HF with congestion (Wet profile)
- Adequate peripheral perfusion - Wet and Warm - Treat hypertension and congestion with Vasodilators, Diuretics
- Poor peripheral perfusion - Wet and Cold - Inotropes, Vasopressors, Diuretics for low SBP; Vasodilators, Diuretics for normal SBP
HF without congestion (Dry profile)
- Adequate peripheral perfusion - Dry and warm - Compensated HF, adjust medication
- Poor peripheral perfusion - Dry and cold - treat hypoperfusion with Fluid Challenge, Inotropic agent
General management and monitoring metrics for acute HF
General:
- Bed rest
- O2 supplementation: NIV, NI-cPAP, Intubation, Mech. ventilation
- Low salt diet
- Fluid restriction
Monitor:
- Vitals: Orthostatic BP, O2 saturation, HR
- Fluid I/O, Weight
- Clinical: signs of peripheral congestion, symptoms of HF
- Electrolytes and renal function
Drug management of acute HF
All options
BP Stable:
- IV Frusemide (diuretic)
- IV nitrate
- Morphine (pain)
BP unstable or deterioration:
- Moderate: Inotropes: Dopamine and Dobutamine
- Severe: Intra-aortic balloon pump, ECMO
Drug management for CHRONIC HF (HFrEF)
All options
4 main pillars:
- ACEi/ ARB + Beta Blocker
- Mineralocorticoid receptor antagonist
- Angiotensin receptor neprilysin inhibitor (ARNI), Ivabradine
- Surgical: e.g. Cardiac resynchronization therapy (CRT)
Additional:
- Nitrate + Hydralazine if cannot tolerant ACEi and ARB
- Diuretics for volume overload
- Anti-coagulants, Digoxin, PCI for A-fib
- CABG/ PCI for CAD
Examples of ACEi and ARB
Indications for HF
ACEi - Captopril, Ramipril
Recommended for all HFrEF patients
ARB - Valsartan, Losartan
For ACEi refractory patients with intractable cough, angioedema
Effect of Beta blocker in HF
Cardioprotective effect, block SNS stimulation
Short-term decrease contractility, increase EF gradually after 1-3 months of use
Increase the dose with time
Long-term symptomatic improvement
Effect of MRA on HF
Spironolactone - reduce HF mortality and morbidity
Eplerenone - reduce MI, HF mortality with less hormonal side effects e.g. gynaecomastia
Effect of Ivabradine on HF
Funny Channel blocker - reduces SA node firing frequency and slows HR
For patients intolerant to Beta-blockers
Treatment options for CHRONIC HF HFpEF/ Diastolic HF**
SGLT-2 inhibitor + ACEi/ ARB = major drugs
Additional:
- Slow HR, BP control: BB, CCB
- Diuretics for volume overload
- CAD - coronary revascularization
