HEART FAILURE

Question 1

Definition

Answer 1

Chronic, progressive condition in which the heart muscle is unable to pump enough blood through to maintain the cardiac output to meet demand —> insufficient oxygen delivery to tissues and fluid accumulation of lungs

Question 2

Clinical Features (3)

Answer 2

• Dyspnea is the essential feature of congestive heart failure
• Left-sided HF associated with symptoms that are predominately respiratory, such as dyspnea on exertion, orthopnea, paroxysmal nocturnal dyspnea, wheezing, and easy fatigability
• Right sided HF mainly associated with peripheral edema, ascites, raised JVP, and hepatomegaly

Question 3

Heart failure with Reduced Ejection Fraction (HF - REF) (6)

Answer 3

• EF is low (<45%)
• Systolic dysfunction, contraction impaired
• Dilatation of the heart, high LV volume
• Added S3 sound
• Main causes: - MI (CAD), Valvular heart disease, dilated cardiomyopathy
• Has effective therapies. The lower the EF, the poorer the survival

Question 4

Heart failure with Preserved Ejection Fraction (HF - PEF) (6)

Answer 4

• EF is equal or more than 50%
• Diastolic dysfunction, relaxation impaired
• Not dilated; Normal LV volume but high LV end-diastolic pressure
• Added S4 sound
• Main causes: LVH, HTN (initially preserved EF but overtime the heart may dilate and lead to systolic dysfunction and reduced EF
• No large scale trials. Can only treat underlying cause, control heart rate to prolong diastole, and diurese the patient

Question 5

NYHA classification of heart failure severity

Answer 5

1. Class I: no symptoms with ordinary physical activity
2. Class II: mild limitation of physical activity. Symptoms with ordinary physical activity
3. Class III: marked limitation of physical activity. Symptoms with less than ordinary physical activity
4. Class IV: unable to perform any physical activity. Symptoms at rest

Question 6

Investigations - Echocardiogram (7)

Answer 6

• Single most important diagnostic test
• Transthoracic echo best initial test
• Estimates ejection fraction: HF-REF vs HF-PEF (systolic vs diastolic dysfunction)
• Shows chamber dilation or hypertrophy
• Underlying cause (wall motion abnormality, valvular disease, cardiomyopathy)
• Severity of LV dysfunction
• Follow up effect of treatment

Question 7

Investigations - ECG (4)

Answer 7

• Arrhythmias (e.g. heart block, A.Fib)
• HF-REF —> evidence of CAD and old MI
• HF-PEF —> evidence of LVH
• Holter monitor may be needed to detect paroxysmal arrhythmias

Question 8

Investigations - Chest X-ray (5)

Answer 8

• Cardiomegaly (dilated cardiomyopathy)
• Dilated upper lobe veins due to congestion
• Pulmonary edema (bat wing appearance)
• Kerly lines due to interstitial edema
• Pleural effusion

Question 9

Investigations - Blood tests (4)

Answer 9

• CBC (to look for anemia as a precipitating factor)
• Renal and liver profile
• BNP (normal BNP excludes CHF; used to determine etiology of acute dyspnea: cardiac vs respiratory)
• Thyroid function (esp. in those with A.Fib, both hypo and hyperthyroid —> HF)

Question 10

Investigations - Cardiac catheterization (2)

Answer 10

• Precise valve diameters and septal defects
• For diagnosis of ischemic HF and revascularization

Question 11

Treatment - Improve survival (5)

Answer 11

1- ACEI/ARB
- Must be given to all patients at all stages
2- B-blockers
- Benefit only with Metoprolol, Bisoprolol, Carvedilol (mneumonic: MBC)
- Anti-ischemic, antiarrhythmic, decrease in HR
- Not given in the acute treatment of HF episode, but improves survival in maintenance treatment
3- Mineralocorticoid antagonists (Spironolocatone)
- Added in more advanced stages of HF (class III and IV)
- SE: hyperkalemia and gynecomastia (less with eplerenone)
4- Hydralazine and isosorbide dinitrates
- Used as vasodilator therapy if an ACEI/ARB can’t be used
5- ARNI (Angiotensin receptor-neprilysin inhibitor)
- Combination of valsatran (ARB) and sacubitril (neprilysin inhibitor)

Question 12

Treatment - Improve symptoms (2)

Answer 12

1- Diuretics
- started from initial therapy
- loop diuretics e.g. furosemide
2- Digitalis
- controversial; used to control symptoms in symptomatic patients on both ACEI and BB)

Question 13

Treatment - Device Therapy (2)

Answer 13

1- ICD (implantable cardioverter-defibrillator)
- Reduces sudden death from ventricular arrhythmias
- Indications:
- EF < 30% on optimal medical therapy
- Previous cardiac arrest due to VT/VF
- Previous MI with non-sustained VT on 24 h monitoring and EF < 35%
- Long QT syndrome, Brugada syndrome, HOCM
2- CRT (cardiac resynchronization therapy) - AKA: biventricular pacemaker
- Persistent symptoms of HF, EF < 35%
- LV systolic dysfunction, dilated, wide QRS

Question 14

Treatment - Surgery (3)

Answer 14

1- Coronary revascularization (if the cause is CAD): to prevent further ischemia and promote recovery of function —> improve symptoms and survival
2- Valve repair/replacement (if the cause is Valvular heart disease)
3- Cardiac transplantation in end-stage HF