19 Pathophysiology of Heart Failure Flashcards
What are the causes of heart failure
1) arrhythmia
2) myocardial heart disease
3) congenital heart disease
4) valve disease
5) pericardial disease
What is the definition of heart failure
Clinical syndrome caused by the abnormality of the heart which cannot maintain BP without support, with characteristic neuronal, hormonal, haemodynamic and renal responses
What is the prevalence in general public and those over 75 years of age
General: 1-3% - 22 million people
>75 years old: 10%
What is its prognosis
50% mortality within 5 years
What are the causes of myocardial heart disease which can predispose patients to heart failure
Coronary artery disease
Cardiomyopathy
Hypertension
Drugs - beta and calcium antagonist
What is the physiological adaptation post-MI
Increased wall stress following MI
Infarct expansion
Late ventricular enlargement (hypertrophy) accompanied with thinning of the wall
Define cardiomyopathy and state its different categories and their respective prevalence
Heart disease without a known cause Hypertrophic cardiomyopathy: 1:500 Dilated cardiomyopathy: 1:5,000 Restrictive cardiomyopathy: 1:10,000 Arrhythmic right ventricular cardiomyopathy: 1:5,000
How does heart failure cause death
1) Progression of HF: increased ventricular wall stress and retention of water and sodium
2) Sudden death: opportunistic arrhythmia and acute coronary event
3) Cardiovascular events: stroke, pulmonary vascular disease
4) Non-cardiovascular events: pneumonia
What are the mediators involved in HF
Constrictor: AVP, Ang II, aldosterone, noradrenaline
Dilator: ANP, prostaglandin
Growth factors: growth hormone, insulin, TNFa
What are the inflammatory markers for HF
- cTn I and T
- Vessel wall expressions: ICAM-1, VCAM-1, E-selectin and P-selectin
- Macrophage: phospholipase A2
What are the symptoms of HF
Tiredness Orthopnoea Breathlessness Oedema Tachycardia
What is the investigations involved to confirm HF
X ray
Echocardiogram
ECG
Identify lifestyle changes and medications for HF
Lifestyle changes: cigarette cessation, stop alcohol, exercise, weight reduction
Medications: Beta blockers, ACE inhibitor (captopril), aldosterone inhibitor (spironoloactone), digoxin, diuretics
Describe the progression of HF
Onset of HF starts with plateau of quality of life during which there is myocardium loss and the BP is compensated by neuronal and hormonal responses. During this period, there is a chance for patient to develop coronary event and sudden death.
After plateau, rapid decrease in quality of life affected by infections
What are the syndromes associated with heart failure
Pulmonary oedema
Cardiogenic shock
Chronic HF
