TOPIC14: heart failure (etiology & diagnosis)

Question 1

What is HF?

Epidemiology and diagnosis

Answer 1

1. progressive condition with several stages, where the heart fails to meet the metabolic demands of the body
2. clinical syndrome resulting from structural/functional abnormality of the heart
3. impairs the ability of the LEFT ventricle to FILL with or to EJECT blood

• lifetime risk for developing HF for all individuals >40yrs is 20% (prevalence increases with age)
• when diagnosed with HF, the risk of dying within 5 years is estimated to 82%
• mortality precedes 50% ay 5 years- poor diagnosis
• primary causes of death include either progressive pump failure or sudden cardiac death secondary to ventricular arrythmia

Question 2

Etiology of acute HF

Answer 2

1) Acute coronary syndrome/ CAD
2) Valvular disease - endocarditis/ aortic dissection
3) myopathies (alcoholic, peripartum)
4) arrythmias
5) HTN
6) Non cardiac origin:
- COPD, pulmonary embolism
- drug abuse
- renal failure, volume overload,anemia
- infection(chagas, HIV), sepsis
- tamponade
- thyrotoxicosis

Question 3

Etiology of chronic HF

Answer 3

1) Ischemic heart disease/ CAD
2) Congenital
3) alcohol/drugs
4) amyloidosis/Sarcoidosis
5) HTN
6) Valvular disease
7) arrythmias
8) RHF: COPD, PE or pulm HTN
9) haemochromatosis
10) nutritional (beri-beri)
11) thyroid disease

Question 4

Stages of HF according to ACC/AHA

Answer 4

Stage A: high risk for HF but without structural heart disease or symptoms of HF (HTN,CHD,DM, metabolic syndrome)

Stage B: structural heart disease without symptoms of HF (previous MI, LVH, decreased EF or asymptomatic valvular disease)

Stage C: structural heart disease with prior or current symptoms of HF (shortness of breath & fatigue, reduced exercise tolerance)

Stage D: refractory HF requiring special intervention
(pts who have marked symptoms at rest despite maximal medical therapy)

Question 5

NYHA classification

Answer 5

Class I: symptoms only with exertion that would limit normal individuals

Class II: symptoms at ordinary exertion

Class III: symptoms at less than ordinary exertion

Class IV: symptoms at rest

Question 6

Systolic HF

Answer 6

• ventricles contract poorly–> increased end- diastolic volume and decreased pressure–> decreased EF <40%
• Heart will be enlarged
• due to AMI, myocarditis, Dilated cardiomyopathy

Question 7

Diastolic HF

Answer 7

• preserved systolic function and EF
• Ventricular filling is impaired due to impaired relaxation of the ventricles or increased stiffness of myocardium, valvular disease or constrictive pericarditis
• this results in increased ventricular filling pressure

Question 8

Right HF

Answer 8

-Due to impaired RV function or due to resistance/obstruction in front of the RV( pulmonary embolism or LVF with backward failure)

signs:

1) peripheral edema and ascites
2) distention/pulsation of neck veins
3) portal HTN with hepatomegaly and GI congestion causing nausea and anorexia
4) facial engorgement, epistaxis, nocturia and depression

Question 9

Left HF

Answer 9

-Due to impaired LV function or due to resistance/ obstruction in front of the LV (aortic stenosis or HTN)

signs:

1) pulmonary congestion and edema
2) dyspnea on exertion, orthopnea, paroxismal nocturnal dyspnea
3) decreased SpO2
4) cough and wheezing
5) blood in sputum
6) fatigue, muscle wasting, weight loss and poor exercise tolerance
7) cold extremeties

Question 10

Biventricular HF causes

Answer 10

• viral myocarditis
• amyloidosis
• Chagas disease
• long standing LVF causing RVF

Question 11

Low CO HF

Answer 11

• CAD
• HTN
• valvular disease
• arrythmias
• pericardial disorder
• drug toxicity

Question 12

high CO HF

Answer 12

• anemia
• thyrotoxicosis
• AV-fistula
• liver cirrhosis
• paget disease
• beri beri disease

Question 13

Diagnosis of HF

Answer 13

1)Medical history (family history, symptoms, complaints)

2) Physical examination:
- shortness of breath at exertion and at rest, fatigue
- tacchycardia, tacchypnoe, raisedJVP, pulm edema, peripheral edema
- AUSCULTATION: crackles in lungs, S3 gallop, possible murmurs

3) Blood test + ABG:
- BNP and other cardiac markers if MI is the cause
- CRP
- Complete blood count
- electrolytes and glucose HYPONATREMIA
- liver-BILIRUBIN renal and thyroid parameters

4) ECG:
- Look for hypertrophy/strain signs
- possible arrythmias
- conduction abnormalities LBBB
- ischemia/infarction (previous or ongoing)

5)CXR:
-ABCDE for LVF
A: alveolar edema (bat’s wings shadowing)
B: Kerley B-lines (interstitial edema)
C: cardiomegaly
D: Dilated prominent upper lobe vessels
E: pleural effusion

5) ECHO:
- cardiomegaly
- confirms diagnosis
- estimates SV,EF,EDV, wall motion
- shows possible valvular damage or pericardial disease

6) ANGIO:
- in case of coronary causes of HF

NOTE: A clinical response to treatment directed at HF alone (eg diuretics) may be a useful adjunct but is not sufficient to establish the diagnosis.

(MPBECEA)

Question 14

TREATMENT

Answer 14

• diuretics (not cure, just decrease edema) *furosemide worsen GFR
• beta blockers only when pt stable up to max tolerated dose
• ACEi IF GFR>30
• ALD ATG
• ANgiotension REC blockers
• statins
• dobutamin
• ischemic: vasodilation (nitrates)
• heart transplant
• CRT
• ICD ( To PREVENT sudden cardiac death, as primary prevention in pts in high risk with no previous episodes or secondary in pts who survived a sudden cardiac death episode) SCD: ventricular arrythmias