Abnormality of cardiac structure and/or function resulting in clinical symptoms (e.g., dyspnea, fatigue) and signs (e.g., edema, rales), hospitalizations, poor quality of life, and shortened survival. It is important to identify the underlying nature of the cardiac disease and the factors that precipitate acute CHF.
Underlying Cardiac Disease
Includes (1) states that depress systolic ventricular function and ejection fraction (coronary artery disease, hypertension, dilated cardiomyopathy, valvular disease, congenital heart disease); and (2) states of heart failure with preserved ejection fraction (e.g., restrictive cardiomyopathies, hypertrophic cardiomyopathy, fibrosis, endomyocardial disorders), also termed diastolic failure.
Acute Precipitating Factors
Include (1) excessive Na+ intake, (2) noncompliance with heart failure medications, (3) acute MI (may be silent), (4) exacerbation of hypertension, (5) acute arrhythmias, (6) infections and/or fever, (7) pulmonary embolism, (8) anemia, (9) thyrotoxicosis, (10) pregnancy, (11) acute myocarditis or infective endocarditis, and (12) certain drugs (e.g., nonsteroidal anti-inflammatory agents, verapamil).
Due to inadequate perfusion of peripheral tissues (fatigue, dyspnea) and elevated intracardiac filling pressures (orthopnea, paroxysmal nocturnal dyspnea, peripheral edema).
Jugular venous distention, S3, pulmonary congestion (rales, dullness over pleural effusion), peripheral edema, hepatomegaly, and ascites. Sinus tachycardia is common.
In pts with diastolic dysfunction, an S4 is often present.
CXR may reveal cardiomegaly, pulmonary vascular redistribution, Kerley B lines, pleural effusions. Left ventricular contraction and diastolic dysfunction can be assessed by echocardiography with Doppler. In addition, echo can identify underlying valvular, pericardial, or congenital heart disease, as well as regional wall motion abnormalities typical of coronary artery disease. Measurement of B-type natriuretic peptide (BNP) or N-terminal pro-BNP differentiates cardiac from pulmonary causes of dyspnea (elevated in the former).
Conditions That Mimic CHF
Pulmonary Disease: Chronic bronchitis, emphysema, and asthma (Chaps. 138 and 140); assess for sputum production and abnormalities on CXR and pulmonary function tests. Other Causes of Peripheral Edema: Liver disease, varicose veins, and cyclic edema, none of which results in jugular venous distention. Edema due to renal dysfunction is often accompanied by elevated serum creatinine and abnormal urinalysis (Chap. 42).
TREATMENT Heart Failure
Aimed at symptomatic relief, prevention of adverse cardiac remodeling, and prolonging survival (See Fig. 133-1). Overview of treatment shown in Table 133-1; notably, ACE inhibitors and beta blockers are cornerstones of therapy in pts with impaired ejection fraction (EF). Once symptoms develop:
Control excess fluid retention: (1) Dietary sodium restriction (eliminate salty foods, e.g., potato chips, canned soups, bacon, salt added at table); more stringent requirements (<2 g NaCl/d) in advanced CHF. If dilutional hyponatremia present, restrict fluid intake (<1000 mL/d). (2) Diuretics: Loop diuretics [e.g., furosemide or torsemide (Table 133-2)] are most potent and, unlike thiazides, remain effective when ...