Heart Failure : Symptom, Pathophysiology, Diagnosis And Treatment
Heart failure (HF) is a clinical syndrome caused by the inability of the heart to pump sufficient blood to meet the metabolic needs of the body. Heart failure can result from any disorder that reduces ventricular filling (diastolic dysfunction) and/or myocardial contractility (systolic dysfunction).
Pathophysiology of Heart Failure :
Causes of systolic dysfunction (decreased contractility) are reduction in muscle mass (e.g., myocardial infarction [MI]), dilated cardiomyopathies, and ventricular hypertrophy. Ventricular hypertrophy can be caused by pressure overload (e.g., systemic or pulmonary hypertension
, aortic or pulmonic valve stenosis) or volume overload (e.g., valvular regurgitation, shunts, high-output states).
Causes of diastolic dysfunction (restriction in ventricular filling) are increased ventricular stiffness, ventricular hypertrophy, infiltrative myocardial diseases, myocardial ischemia and infarction, mitral or tricuspid valve stenosis, and pericardial disease (e.g., pericarditis, pericardial tamponade).
The most common underlying etiologies are ischemic heart disease, hypertension
, or both.
Diagnosis of Heart Failure :
A diagnosis of HF should be considered in patients exhibiting characteristic signs and symptoms. A complete history and physical examination with appropriate laboratory testing are essential in the initial evaluation of patients suspected of having HF.
Ventricular hypertrophy can be demonstrated on chest x-ray or electrocardiogram (ECG).
Treatment of Heart Failure :
The first step in managing chronic HF is to determine the etiology or precipitating factors. Treatment of underlying disorders (e.g., anemia, hyperthyroidism) may obviate the need for treatment of HF.
Nonpharmacologic interventions include cardiac rehabilitation and restriction of fluid intake (maximum 2 L/day from all sources) and dietary sodium (approximately 1.5 to 2 g of sodium per day).
Standard First Line Therapies :
– ACE Inhibitors
– Beta Bloker
– Diuretic Drugs