Acute Heart Failure(AHF)## causes of acute heart failure##features and management of acute heart failure (AHF)

 

 Acute Heart Failure

Introduction

Definition: Heart failure describes the clinical syndrome that develops when the heart not maintain adequate output, or can do so only at the expense of elevated ventricular filling pressure.

Etiology

Almost all forms of heart disease can lead to heart failure. An accurate aetiological diagnosis is important because treatment of the underlying cause may reverse heart failure or prevent its progression.

Commonest causes:

1. Myocardial Infarction (IHD)-35–40%

2. Dilated cardiomyopathy (DCM) 30–34%

3. Hypertension (15–20%)

4. Increased metabolic demand(high output)- e.g.

a. Pregnancy,

b. Thyrotoxicosis,

c. Anaemia

       Others:

✔Aortic stenosis (left heart failure)

✔Pulmonary stenosis (right heart failure)

✔Pulmonary hypertension

✔Atrial fibrillation

✔Myocarditis

✔Complete heart block

✔Ventricular septal defect

✔Atrial septal defect

✔Tachycardia

Important aspects of Pathophysiology

➣Ventricular dilatation

➣Myocyte hypertrophy

➣Increased ANP secretion

➣Stimulation of the renin–angiotensin–aldosterone system

➣Salt and water retention (promoted by the release of aldosteroneie. secondary hyperaldosteronism)

➣Sympathetic stimulation

➣Peripheral vasoconstriction

➣high left and right atrial pressures Pulmonary and peripheral oedema

☞The proportion of blood ejected with each heart beat (ejection fraction) is reduced early in heart failure.

☞In more severe myocardial dysfunction, cardiac output can be maintained only by a large increase in venous pressure and/or marked sinus tachycardia à accumulation of interstitial and alveolar fluid dyspnoea

Types of heart failure

• Acute and

• Chronic heart failure

Again,

• Left heart failure (due to)

   ➣IHD**

   ➣Valvular heart disease and

   ➣Hypertension

• Right heart failure (due to)

     ➣Chronic LVF**

      ➣Primary and secondary pulmonary           hypertension

     ➣Right ventricular infarction,

     ➣Adult congenital heart disease.

• Biventricular heart failure

      Also,

    >Diastolic dysfunction

     >Constrictive pericarditis

     >Restrictive cardiomyopathy

   >  Left ventricular hypertrophy & fibrosis

     >Cardiac tamponade

    > systolic dysfunction

{Diastolic heart failure is a syndrome consisting of sign-symptoms of heart failure with preserved left ventricular ejection fraction above 45–50% and abnormal left ventricular relaxation assessed by echocardiography. There is increased stiffness in the ventricular wall}

Clinical features

Symptoms:

• Exertional dyspnoea

• Orthopnoea

• Paroxysmal nocturnal dyspnoea

Signs:

• Cardiomegaly (Shifted apex)

• Third and fourth heart sounds

• Elevated JVP

• Tachycardia

• Hypotension

• Bi-basal crackles

• Pleural effusion

• Peripheral ankle oedema

• Ascites

• Tender hepatomegaly.

Left heart failure-

➣Raised JVP+/++

➣Pitting oedema+/++

➣Pulmonary oedema (basal creps)

Also-

➣Cardiomegaly

➣Pleural effusions

Right heart failure.

➣Raised JVP +++

➣Hepatomegaly

➣Ascites

➣Peripheral pitting oedema +++

Clinical assessment

1. A sudden onset of dyspnoea at rest

2. Orthopnoea

3. Sweating

4. Agitated,

5. Pale and clammy

On Examination:

6. The peripheries are cool

7. Tachycardia

8. The BP is usually high (because of sympathetic nervous system activation)but may be normal or low if the patient is in cardiogenic shock.

9. The jugular venous pressure (

JVP) is usually elevated

 particularly when associated with fluid overload or right heart failure.

10. A ‘gallop’ rhythm (a third heart sound) may be heard.

11. Crepitations

 at the lung bases (pulmonary oedema) or throughout the lungs if pulmonary oedema is severe.

12. Expiratory 

wheeze 

often found (which 

confuses with asthma

)

D/D

• Acute Exacerbation of COPD

• Acute Brochial Asthma

• Pulmonary Embolism

Investigations for Acute Heart failure (AHF)

Initial investigations performed in the emergency room should include the following-

A. 12-lead ECG

to look for

a. acute coronary syndromes,

b. left ventricular hypertrophy,

c. atrial fibrillation,

d. valvular heart disease,

e. Left bundle branch block

B. Chest X-ray

. Look for

a. Cardiomegaly,

b. Pulmonary congestion with upper lobe diversion,

c. Pulmonary oedema

d. Pleural effusion

C.Blood tests

.

a. CBC

 (To look for Hb% )

b. Liver function tests(ALT)

c. Blood urea

(to identify renal dysfunction )

 and 

S. Electrolytes

d. Blood Glucose

Also (when conditions permit / available)-

e. Plasma BNP or NTproBNP

 (BNP >100 pg/mL or NTproBNP>300 pg/mL) indicates heart failure.

f. Cardiac Enzyme

Troponin I/CKMB

to identify Acute MI

D.Echocardiography

• Systolic and diastolic function,

• Regional wall motion (indicates IHD)

also-

• Cardiac chamber dimension,

• Valvular heart disease,

Management of Acute heart failure

AHF has a poor prognosis with a 60-day mortality rate of nearly 10%.

So, This is an acute medical emergency:

Patient should be treated in high dependancy unit

with continuous monitoring of cardiac rhythm, BP and pulse oximetry.

1. Bed rest in propped up position (to reduce pulmonary   congestion).

2. High-flow oxygen- Non-invasive positive pressure ventilation (NIPPV) or (continuous positive airways pressure (CPAP) may be needed

3. Loop diuretics

Loop diuretics(such asFrusemide )

(50–100 mg IV)

4.  Glyceryl Trinitrate (nitroglycerine)

IV 

 (10–200 mcg/min)

Or

Glyceryl Trinitrate (nitroglycerine)

Buccal 

 2–5 mg, titrated upwards every 10 minutess (until clinical improvement occurs or systolic BP falls to less than 110 mmHg.)

If these measures prove ineffective-

5. Inotropic agents – particularly in hypotensive patients.

• Dobutamine

 2–20 μg/kg per min (usually starts with 5mcg/min, may need highdose in patients on betablockers)

• and 

Norepinephrine (Noradrenaline)

If facilities available-

6. Insertion of an intra-aortic balloon pump (may be beneficial in patients with acute cardiogenic pulmonary oedema and shock)

Further management (may be considered)-

7. Low-molecular-weight heparin

 - 

Enoxaparin 

1 mg/kg s.c. twice daily if Acute Coronary Syndrome supervenes or 40 mg s.c. daily as a prophylaxis.

When Good Response achieved-

8. Angiotensin-converting enzyme (ACE) inhibitors

.