Congestive Heart Failure: Diagnosis
1. Cardiac magnetic resonance imaging (MRI)
A cardiac MRI is a much more detailed diagnosis compared to an ultrasound. It is a non-invasive imaging test performed to assess the cardiovascular system. The patient is made to lie on a movable bed, which is then inserted into a machine. All the tissues and organs in the body carry water. Radio waves are transmitted through the tissues, and the energy is absorbed by the water to reflect images of the internal body. The test can help to identify abnormalities of the pulmonary vein and myocardium.
2. Cardiac computerized tomography (CT) scan
Cardiac CT scan is a non-invasive approach to evaluate the heart and chest area. The patient is made to lie on a movable bed, which is then inserted into a doughnut shaped machine. An X-ray tube is used for imaging the heart and chest, which is examined through a computer. The test usually takes about 20 minutes following which the patient is immediately allowed to leave. The test is used to identify arrhythmia and examine the coronary arteries.
3. Ejection fraction
Ejection fraction can be measured through a non-invasive ECG. Ejection fraction determines the heart’s pumping ability, measured with respect to the amount of blood pumped out of the ventricle with each beat. A healthy heart will have an ejection fraction of over 50%. The test may take 5 to 15 minutes and the patient is allowed to leave immediately after the test.
4. Coronary catheterization (angiogram)
Coronary catherterization is an invasive diagnostic approach to examine the coronary arteries. In this procedure, the patient is first injected with a mild sedative to relax. Local anesthesia is intravenously injected, and a long, flexible tube (catheter) is inserted into the patient’s groin or arm, through a small incision. The practitioner threads the catheter into the cardiac arteries. A contrast material (dye) is intravenously injected through the catheter into the opening of a coronary artery. An X-ray camera is then used to take pictures of the arteries and heart chambers. This test can help to identify coronary artery disease and other abnormalities. The procedure takes about 40 minutes to an hour. The patient is usually kept under overnight observation after the test.
5. Blood tests
Blood tests such as liver function tests, electrolyte test, and complete blood count, are often conducted for a complete analysis of the blood. The patient’s blood sample is also tested for C-reactive protein, if infection is suspected. An elevation in B-type natriuretic peptide (BNP) is a specific indicator of heart failure. A blood test is minimally invasive and usually takes about 5 minutes. The patient is not kept under observation, and the results are discussed later.
6. Echocardiogram (ECG)
Echocardiogram is the gold standard in the diagnosis of heart failure. It is a non-invasive imaging test, which uses ultrasound waves to produce images of the heart and related areas. A cardiac sonographer conducts the test, which can take from 40 minutes to an hour. During the test, a sound wave transducer is placed on the patient’s chest with a small amount of gel. Ultrasound waves are transmitted through the transducer to reflect images. The test helps to examine the heart for blood flow pattern, muscle weakness, valve abnormalities, and other signs of heart failure. The patient is not required to be kept under observation before or after the test.
7. Electrocardiogram (ECG)
ECG is a non-invasive diagnosis to examine the electrical activity of the heart. In this procedure, a small amount of gel is applied on the patient’s upper chest region. ECG leads are attached to six pre-defined positions, and electrical impulses are transmitted from the heart. The test can evaluate the heart for arrhythmia (abnormal heart rhythm), hypertrophy (increased thickness), or ischemic heart disease. An ECG is a safe procedure with no radiation exposure. The test takes about 10 to 15 minutes, and the patient is not required to be under observation afterwards.
8. Chest X-ray
Chest X-ray is a non-invasive imaging diagnosis, which provides an overview of heart and related areas. A chest X-ray is often useful in the diagnosis of congestive heart failure. In case of left ventricular failure, it can help identify evidence of vascular redistribution and interstitial edema. A chest X-ray can also be examined for cardiomegaly (visible enlargement of heart), by evaluating the proportion of the heart size to the chest. An X-ray usually takes about 5 minutes and the patient is not kept under observation.
9. Physical examination
A physical examination can help identify visible symptoms of congestive heart failure such as distended neck veins, swelling of the limbs due to fluid accumulation (peripheral edema), abdominal swelling, and enlarged liver. Heart failure can also lead to respiratory infections visible through persistent cough and wheezing. A careful examination of symptoms along with patient’s medical history provides the basis for further diagnosis.