- Acute versus chronic
- Left versus right and biventricular or congestive heart failure (CCF)
- Forward versus backward
- Systolic versus diastolic
- low output versus high output
ACUTE VERSUS CHRONIC HEART FAILURE
Acute heart failure: Heart failure developing suddenly in hours a day in a previously asymptomatic patient is called acute heart failure.Causes: The causes of acute heart failure occur when a previously normal person suddenly develops a serious anatomical or functional abnormality and time is not sufficient for compensatory mechanisms to operate such conditions are:
- Massive acute myocardial infarction.
- Tachyarrhythmias with very rapid heart rate.
- Rupture of valve secondary to infective endocarditis.
Chronic heart failure: Heart failure developing gradually is called chronic heart failure. In this type of failure, a variety of compensatory changes may take place in the early phase to improve cardiac function. These adaptive mechanisms allow the patient to adjust and tolerate not only the anatomic abnormality but also a reduction in cardiac output with less difficulty.
LEFT VERSUS RIGHT AND BIVENTRICULAR OR CONGESTIVE HEART FAILURE
Left-sided heart failure: The left-sided heart failure is characterized by a reduction in effective left ventricular output for a given pulmonary venous or left atrial pressure. An acute increase in left atrial pressure may cause pulmonary congestion or pulmonary edema, while the chronic increase in left atrial pressure leads to reflects pulmonary vasoconstriction which protects the patient from pulmonary edema at the cost of increasing pulmonary hypertension (as a compensatory mechanism).Causes of left heart failure
- Ischemic heart disease (commonest)
- Systemic hypertension
- Mitral and aortic valve disease
- Cardiomyopathies
Causes of right heart failure
Biventricular or congestive cardiac failure (CCF): When both sides of the heart are involved, features of both right and left heart failure are present. In most of the patients right heart failure is a result of preexisting left heart failure.
- Secondary to left heart failure (most common)
- Chronic lung disease (Causing cor-pulmonale)
- Pulmonary embolism or pulmonary hypertension
- Tricuspid and pulmonary valve disease
- ASD & VSD
- Right ventricular cardiomyopathy
Biventricular or congestive cardiac failure (CCF): When both sides of the heart are involved, features of both right and left heart failure are present. In most of the patients right heart failure is a result of preexisting left heart failure.
FORWARD VERSUS BACKWARD FAILURE
Forward failure: In some patients with cardiac failure predominant problem is an inadequate cardiac output that leads to diminished perfusion of vital organs, leading to ischemia of these organs this is called forward failure. Ischemia of the brain causes mental confusion, ischemia of skeletal muscles leads to weakness, ischemia of kidneys causes sodium and water retention leading to symptoms of heart failure.Backward Failure: In some patients, cardiac failure presents mainly with features of damming of blood into the venous system such as lung congestion in left heart failure and congestion of liver, spleen and other areas in right heart failure.
SYSTOLIC VERSUS DIASTOLIC FAILURE
In the majority of patients heart failure is due to combining systolic and diastolic dysfunction, however, isolated systolic or diastolic dysfunction may be present.Systolic Failure: Heart failure may develop as a result of impaired myocardial contraction (systolic dysfunction). The most common cause of systolic ventricular dysfunction is ischemic heart disease usually after myocardial infarction. The left ventricle is usually dilated and fails to contract normally resulting in symptoms of predominantly forward failure.
Diastolic Failure: Heart failure may develop due to poor ventricular filling caused by impaired ventricular relaxation (diastolic dysfunction). The most common cause is left ventricular hypertrophy as a result of hypertension and coronary artery disease. Other causes of diastolic dysfunction are hypertrophic and restrictive cardiomyopathy, diabetes, and pericardial disease.