Treatment of Heart Failure, full detailed approach

Here we are going to discuss how to manage a case of Chronic Heart Failure, the full approach to treatment .

1. Bed rest 

- Rest until clinical improvement.
- Rest increases renal blood flow and help diuresis .
But there are some complications of prolonged rest like DVT, Pulmonary embolism, Constipation and osteoporosis.

2. Diet and other measures

  • Salt restriction (sodium intake about 2 gm/d).. KCI is a salt containing no sodium.
  • Fluid restriction: "fluid chart" , to avoid volume overload, with monitoring of urine output, also to avoid hy onatremia.
Required fluid = 500 ml + the volume of urine output in the previous day.

  • Avoid heavy meals and avoid Alcohol as it has a negative inotropic effect .
  • Weight reduction in obeses people to avoid cardiac load .
  • It is better to give Influenza and Pneumococcal vaccine and stop smoking.

3. Digitalis

Mechanism of action:

- Increases muscle contraction by sliding actin over myosin .
- K inhibits the action of Digitalis on  ATPase --> low K --> Digitalis toxicity.
also, we use K in treatment of digitalis toxicity.

Uses :
  1. Heart failure, the use of digitalis is essential with associated AF .
  2. Arrhythmias: - Atrial fibrillation  - Atrial flutter  - Supraventricular tachycardia.
Dose : 

- 85 % excreted in the urine, 15 % through biliary excretion.
- Therapeutic level will be achieved after 5 days of daily maintenance therapy (cumulative method )

A.  Cumulative method (maintenance dose from the start) 
  • 0.125 - 0.25 mg / day.
  • Response after about 5 days .
  • Tablet = 0.25 mg (lanoxin or cardixin).
B. Rapid digitalization (loading method) :
Example : 
Loading dose is about 1-1.5 mg over 24 hours 
Give 0.25 - 0.5 mg orally or IV (over 30 m) followed by:

What are the indications of IV digitalization ?

Half life is 5 days, metabolized mainly in the liver, only 15 % excreted in the kidney, to reach steady state it must be taken for about 3 weeks.
It is rapidly acting, onset of action 5-10 minutes, peak 60 minutes after IV injection, excreted through the kidney.
Digitalis toxicity clinical picture and management : discussed Here
Contraindications of Digitalis 

4. Diuretics 

Aim : Sodium and water excretion, which leads to :
- Decrease Sodium retention.
-Decrease venous pressure, this leads to relief of PVC & SVC .
- Fluid loss with reduction of heart load.
- Acts on loop of Henle .
- It is a venodilator of pulmonary veins.
- Decreases PVC and SVC .
- Dose: (40-160 mg/d) oral or injection. ( Tablet 40 mg,, Amp: 20 mg, 40 mg IV, I.M.)
- Act mainly on distal tubules
- Dihydrochlorothiazide 25 - 50 mg/d.
- Chlorothalidone 25-100 mg/d. (Long acting) .

Thiazides in combination with loop diuretics have a synergistic action and greater diuretic effect.

Side effects of Lasix and  Thiazides

K- sparing diuretics:
They can be combined with lasix and thiazides.
* Spironolactone acts through aldosterone antagonism in the distal tubules.
(Tab. 25 mg) we give up to 200 mg/day. Hyperkalemia and gynaecomastia are side effects. Spironolactone may reduce the process of remodeling.
* Other K sparing diuretics. e.g triamterene, amiloride (5-20 mg/d).
They act directly on ion transport in the distal tubules with no aldosterone antagonism, (inhibit Na channel) so they inhibit reabsorption of Na and secretion of K ions.

* Oral, suppositories, IV.
* It is usually used in cases of heart failure with superimposed bronchospasm.
* IV injection must be very slowly to avoid arrhythmia.
* It is bronchodilator.
* It is + ve inotropic.
* It has a diuretic effect (due to t renal blood flow).

5. Vasodilators 

A. Venodilators
Value: decrease venous pressure, this will relieve SVC and PVC.
Decrease VR -->  decrease Pre-load 

B. Arterial vasodilatation 
Value : Decrease peripheral resistance thus decrease the After-load , which improves myocardial efficiency ,so increases Cardiac output .

* ACE inhibitors are the best vasodilators in cases of heart failure. Captopril (12.5 mg/8hr. up to50 mg /8hr.), ramipril (2.5 mg/12hr up to 5 mg/12hr)or enlapril (2.5-10 mg/12 hr).
* To get the benefit of these vasodilators, keep the systolic blood pressure above 100 mmHg. ACE inhibitors also lead to reduction of the process of remodeling.

6. Potent Inotropics 

(Used in intractable or refractory failure)

7. Treatment of Precipitating factors

Surgery e.g Valvotomy or intraaortic balloon .

8. Treatment of Complications of heart failure 

Anticoagulants for patients with atrial fibrillation or with history of thrombo-embolism and in cases with dilated cardiomyopathy.

Antiarrhythmic drugs e.g for atrial fibrillation, ventricular tachycardia (arrhythmia may lead to deterioration of symptoms). Electrolyte disturbances and digitalis toxicity must be diagnosed early and treated .

Cardiac resynchronization: may patients with HF developed LBBB which delays and discoordinates contraction, so insertion of pacemaker to resynchronize contraction improves both the hemodynamics and symptoms.

Monitoring of kidney functions and urine output to avoid renal failure.
Treatment of Heart Failure, full detailed approach
Dr.Tamer Mobarak


No comments
Post a Comment