Electrocardiogram
An electrocardiogram observes the electric activity of the heart and assists in identifying abnormalities in the heart rhythm.
Echocardiogram
An echocardiogram is a form of ultrasound that produces pictures of the heart via sound waves. The picture can depict how much blood is being pumped out of the heart and check for any unusual thing in the pumping ability of the heart.
Blood tests
Most doctors recommend a blood test to help diagnose cardiac asthma that can cause heart failure, check for markers of elevated fluid and be sure there is no other potential cause of the symptoms.
Chest X-ray
Chest X-rays are used to know if the heart is enlarged or there is fluid in the lungs.
Breathing tests
Doctors can also recommend breathing tests such as a spirometry test or a peak flow test to check for any lung problems.
Other imaging techniques
A CT or MRI scan can also be used to produce images to check the state of your heart.