Chronic Heart Failure - Epidemiology, Investigation and Diagnosis!

Question 1

Define heart failure.

Answer 1

A clinical syndrome comprising of dyspnoea, fatigue or fluid retention due to cardiac dysfunction, either at rest or on exertion, with accompanying neurohormonal activation.

Question 2

When diagnosing heart failure what is important to remember?

Answer 2

Heart failure is not a final diagnosis and the term should be qualified by the underlying structural abnormality and cause heart failure due to LVSD due to IHD or heart failure due to severe aortic stenosis.

Question 3

IS it a common condition?

Answer 3

Relatively common prevalence.
Incidence increased with age. Mean age of 74.
Prevalence of heart failure 0.4-2%.

Question 4

What factors increase incidence of CHF?

Answer 4

Treatment of AMI, aging population, hypertension, CHD, obesity, diabetes, HLP.

Question 5

What factors decrease incidence of CHF?

Answer 5

Treatment/diagnosis of HLP, hypertension, CHD, diabetes, obesity, treatment of CHF.

Question 6

The one year survival rate for heart failure is worse than that for what?

Answer 6

Cancer of the breast, uterus, prostate and bladder.

Question 7

Why is inpatient cost such a high for CHF?

Answer 7

When you’re admitted with heart failure tend to stay in for 10-12 days.

Question 8

Once you’ve been admitted to hospital with HF once, are you likely to never return?

Answer 8

Likely to be readmitted after heart failure (almost 1/3 readmitted within 12 weeks).

Question 9

When are re-admissions more likely to happen?

Answer 9

Most likely to be re-admitted early on, as time goes on less and less likely to be re-admitted.

Question 10

What symptoms do people with HF suffer?

Answer 10

SoB, fatigue, oedema, reduced exercise capacity.

Question 11

What signs would you look for in HF?

Answer 11

Oedema, tachycardia, raised JVP, chest crepitations or effusions, 3rd heart sound, displaced or abnormal apex beat.

Question 12

When might it be quite easy to make a HF diagnosed?

Answer 12

CXR Massive heart, already have pacemaker.
Pulmonary congestion.
Signs and symptoms as above.

Question 13

To make a diagnosis of HF what do you need?

Answer 13

Symptoms or signs of HF (rest or exercise) and
Objective evidence of cardiac dysfunction and (in doubtful cases)
Response to therapy (diuretics).

Question 14

What imaging techniques can be used to gain objective evidence of cardiac dysfunction?

Answer 14

Echocardiography, radionucleide ventriculography (RNVG/MUGA), MRI, left ventriculography.

Question 15

What is the best imaging technique to use?

Answer 15

Echocardiography - most practical and no radiation.

Current W/L > 6 months in grampian.

Question 16

Is screening the answer? - What are the potential screening tests?

Answer 16

??

12 lead ECG
LVSD v unlikely if ECG normal (90-95% sensitive).
Problems with confidence of interpretation in primary care, must be entirely normal or else loses reliability.

BNP (brain (b-type) natriuretic peptide)
Amino acid peptide, can be measured easily in the blood
Elevated in HF ,therefore low BNP excludes HF
May be useful diagnostic test - may soon come into widespread clinical use.

Question 17

Why would BNP be a good screening test for HF?

Answer 17

Highly sensitive test for HF, stable for up to 72 hours, bedside testing available if desired, relatively in expensive.
Elevated BNP indicates need for echo/cardio assessment.
Vast majority of trials suggest it is useful and reliable.

Question 18

HF is not a final diagnosis - what do you need to find out?

Answer 18

What is the underlying structural abnormality? And what’s causing it?

Question 19

If sufficiently severe enough almost any structural cardiac abnormality will cause HF, give examples.

Answer 19

LV systolic dysfunction – many causes
Valvular heart disease
Pericardial constriction or effusion
LV diastolic dysfunction/heart failure with preserved systolic function/heart failure with normal ejection fraction
Cardiac arrhythmias: tachy or brady
Myocardial ischaemia/infarction (usually via LVSD)
Restrictive cardiomyopathy eg amyloid, HCM
Right ventricular failure: primary or secondary to pul hypertension