Congestive heart failure
The main function of heart is to pump blood to tissue for metabolism during rest & activity.
When function of heart becomes impaired it can’t pump blood to tissues in adequate amount. Such a state is called heart failure.
It is clinical syndrome characterized by difficulty in breathing.,fluid retention effort intolerance & decreased longevity caused due to identifyable abnormality of cardiac function.
Causes
1.Congenital heart diseases
-Mitral valve disease
-Atrial septal defect
2.
Hypertension 3. Coronary arterial disease
-Myocardial infarction
-Ischaemia
4. Arrhythmias
-Tachycardia
-Bradycardia
5.Alcohol & drugs
-B-blockers
6.Pericardial disease
-Pericarditis
-Pericardial effusion
In patient with heart disease the factoers which ay precipitate heart failure include-
Infections,anaemia, pregnancy,infective endocarditis,Rheumatic myocarditis,thyrotoxicosis etc.
Pathophysiology
In heart failure there is decrease in stroke volume & cardiac output.It leads to inadequate tissue perfusion.Compensatory mechanisms take part to restore tissue.
1.Renin production increases from juxta-glomerular apparatus in the kidney,increased levels of angiotensin II leads to vasoconstriction.
2.Increaswd production of aldosterone hormone increased sodium water retention causing oedema.
3.Increased levels jof epinephrine & nor-epinephrine.
4.Increased production of vasopressin hormone.
These mechanisms collectively increase myocardial contractility,increase systemic vascular resistance & sodium water retention.
In normal heart these mechanisms restore tissue perfusion.In failing heart it leads to decrease in CO due to increase in systemic vascular resistence.Arrhythmias may also result due to increase in level of serum catecholamine.
Clinical features
NYHA h as categorized this disease into four classes-
I. asymptomatic(no functional limitation)
II. Symptomatic on extra exertion
III. Symtoatic on mild
IV. Symtoatic at rest(severe functional limitation)
In these patioents,usually signs Right & left
ventricular failure can be seen.
Signs of right ventricular failure are-
1.Raised jugular venous pressure.
2.Hepatomegalt & slenomegaly
3.Oedema(Pittings type is first observed in feet of patients who are mobile.Patients who are bed ridden pitting oedema is first seen over sacrum)Oedema in heart failure is the result of Na & water retention.
4.Cyanosis-
Sites for peripheral cyanosis(nails,tips of nose,ear lobules)
Signs of left ventricular failure
1.Dyspnoea which appears when climbing stairs, or even an mild exertions.
The patient suddenly wakes up in middle of night then goesa to the window opens it & tries to get some relief from fresh air,this type of dyspnoea is called parosysmal nocturmal dyspnoea.
In orthopnea patient feels difficulty in breathing in flat position but it relieves in sitting position.
2.Cough
3.Fatiguability & weakness
4.Pulse- fast in left ventricular failure
5.Blood pressure-fall down
6.central cyanosis
7.Chest examination
-Crepitations will be heard
8.Precardial examination
-3rd & 4th heart sounds may be present with gallop rhythm
Present of left ventricular failure for a long time leads to right ventricular failure.
Investigations done
-Chest X-Ray
-ECG
Aims of management
1.Achieve improvement in symptoms
a.Diuretics for reducing oedema
b.Digoxin for increasing cardiac contractility but slows down heart rate.
c.ACE inhibitors
2.Achieve improvement in survival
a.ACE inhibitors
b.B-blockers
c.Hydralazine with oral nitrates
d.Spironolactone
Proper management
A.Correct diagnosis of type of heart disease(valvular heart disease,hypertension)
B.Indentification of factors responsible precipitation of heart failure(anemia,infection)
C.Measures to be initiated immediatery to control CCF
1.Measures to decrease load to heart
-Rest
-ACE inhibitors(Enalapril)
-ACE receptor blockers(Losarton)
2.Measures to improve cardiac contractility
-Digitalis
3.Measures to reduce Na &H2O retention in body
-Dietary restriction
-Diuretics(frusemide)