Heart Failure - Chronic Công cụ chẩn đoán

Laboratory Tests and Ancillaries

Laboratory testing will confirm the presence of heart failure and may show the presence of disorders that can lead to or exacerbate heart failure and may help guide appropriate management.  

Patients with HFpEF are recommended to have screening for and treatment of etiologies and cardiovascular and non-cardiovascular comorbidities.  

For the diagnosis of HFpEF and HFmrEF, spontaneous or provokable increased left ventricular filling pressures should be confirmed in patients with a left ventricular ejection fraction of >40% via elevated levels of natriuretic peptides, diastolic function on echocardiography or invasive hemodynamic measurement. Additional findings supporting an HFpEF diagnosis include an increase in the left ventricular mass index and/or left atrial volume index.  

Tests to Consider in All Patients  

The initial evaluation in patients suspected of heart failure includes but is not limited to complete blood count (CBC), serum electrolytes (including sodium, potassium, calcium, and magnesium), blood urea nitrogen (BUN), creatinine or estimated glomerular filtration rate (eGFR), albumin, cardiac enzymes, liver enzymes, bilirubin, serum ferritin, transferrin saturation (TSAT), total iron-binding capacity (TIBC), blood lipids, blood glucose, international normalized ratio (INR), C-reactive protein (CRP), thyroid function, and urinalysis. These initial tests are used to detect reversible or treatable causes of heart failure and comorbidities interfering with heart failure.  

Natriuretic peptides (B-type natriuretic peptide [BNP], N-terminal pro B-type natriuretic peptide [NT-proBNP], or mid-regional atrial natriuretic peptide [MR-proANP]) are also requested.  

In an ambulatory setting, elevated levels are considered if BNP is ≥35 pg/mL or NT-proBNP is ≥125 pg/mL. Among hospitalized patients, elevated levels are considered if BNP is ≥100 pg/mL or NT-proBNP is ≥300 pg/mL. Natriuretic peptides are useful for differentiating dyspnea caused by heart failure from dyspnea due to other causes. They are used in patients in whom the diagnosis of heart failure is uncertain and when an echocardiogram cannot be performed. They may also be helpful in establishing disease severity, stratifying risk, and obtaining prognostic information. Natriuretic peptides are recommended biomarkers to be used to screen high-risk patients for heart failure.  

The most common findings in a 12-Lead Electrocardiogram (ECG) are nonspecific repolarization abnormalities (ST-T wave changes). Abnormalities are usually nonspecific (including left ventricular hypertrophy, Q wave, sinus tachycardia, and atrial fibrillation). Conduction abnormalities may also be seen (eg left bundle branch block [LBBB], first-degree atrioventricular (AV) block, left anterior hemiblock, and nonspecific intraventricular conduction delays). Information obtained from an ECG can assist in treatment planning and is of prognostic importance. Normal ECG makes the diagnosis of heart failure due to left ventricular systolic dysfunction less likely.  

Tests to Consider in Selected Patients  

Cardiac catheterization is considered in patients who are being evaluated for heart transplantation or mechanical circulatory support. It evaluates cardiac function and pulmonary arterial resistance. It may be performed in cases of uncertain diagnosis (eg early HFpEF). A right heart catheterization should be considered in patients in whom heart failure is thought to be caused by congenital heart disease, constrictive pericarditis, restrictive cardiomyopathy, and high output states. It may also be considered to determine the patient’s volume status.  

Cardiopulmonary exercise testing detects reversible myocardial ischemia and investigates the cause of dyspnea. It is used in the objective evaluation of exercise and functional capacity and exertional symptoms to aid in prescribing an exercise training program. It is also used for evaluating patients for heart transplantation and/or mechanical circulatory support and to obtain prognostic information. An alternative option to measure the patient’s exercise capacity is the 6-minute walk test.  

Endomyocardial biopsy may be useful in identifying specific diagnosis which would influence treatment decisions. It may be indicated rarely in patients with dilated cardiomyopathy with recent onset of symptoms and where heart failure has been excluded by angiography and in primary myocardial diseases like endomyocardial fibrosis and amyloid heart disease. It may also be used in patients with rapidly progressive clinical heart failure or ventricular dysfunction despite appropriate medical treatment and those who are suspected of having myocarditis or infiltrative diseases (eg amyloidosis).  

Spirometry and pulmonary function tests may be used to assess the potential contribution of lung disease to the patient’s dyspnea. They may demonstrate or exclude concomitant smoking-related or other respiratory causes of airway limitation.  

Imaging

Tests to Consider in All Patients  

Chest radiography (X-ray) is useful to determine the heart size, presence of pulmonary congestion, detection of pulmonary and other diseases, and proper placement of an implanted cardiac device. A normal chest X-ray does not exclude the diagnosis of heart failure. Common abnormal findings are pulmonary venous redistribution with upper lobe blood diversion.  

Transthoracic echocardiography is the most useful initial investigation performed immediately to confirm the diagnosis in patients suspected of heart failure. It evaluates the cardiac structure and function (eg chamber volumes or sizes, left ventricular systolic function by left ventricular ejection fraction, diastolic function, hemodynamics, wall thickness, and valvular structure and function), assists in treatment management, and obtains prognostic information. Women with HFpEF have more significant concentric left ventricular remodeling and more impaired diastolic relaxation compared with men with HFpEF. It may also be utilized to exclude correctable causes of heart failure.  

Tests to Consider in Selected Patients  

Cardiac magnetic resonance imaging (CMRI) may be performed in selected patients. It evaluates the cardiac structure and function, measures left ventricular ejection fraction, assesses myocardial scarring, and characterizes cardiac tissue, especially in patients with inadequate echocardiographic images or where there are inconclusive or incomplete echocardiographic findings. It is also useful in the work-up of patients suspected of cardiomyopathy, arrhythmias, cardiac tumors or cardiac involvement by a tumor, pericardial disease, myocarditis, cardiac sarcoidosis, and complex congenital heart disease.  

Coronary angiography is recommended in patients with angina pectoris despite medical therapy or symptomatic ventricular arrhythmias who are suitable for coronary revascularization to evaluate the coronary anatomy (ie establishes the presence and extent of CAD). It is also considered in patients with evidence of reversible myocardial ischemia on noninvasive testing, especially if the ejection fraction is decreased. A multidetector computed tomography (MDCT) study may be used as an alternative to invasive coronary angiography in select patients to rule out significant CAD.  

Myocardial perfusion/ischemia imaging (eg stress echocardiography, CMRI, single photon emission computed tomography [SPECT], or positron emission tomography [PET]) is an alternative imaging modality in patients with unsatisfactory echocardiographic findings or when the degree of left ventricular ejection fraction influences the treatment management. It is considered in patients who are suspected to have CAD and who are suitable for coronary revascularization.