Imaging & Diagnosis
 Serving newborns to the elderly, the Cardiology Department of the Regional Heart Program performs approximately 30,500 cardiac diagnostic studies each year, using both portable and department-based diagnostic technologies. Cardiology studies are a team effort, each type of study involving specific medical professionals including cardiologists, nurses, technologists and radiologists. Information from these studies help cardiologists diagnose a patient's condition and recommend the most effective course of treatment.
Echocardiograms
Holter Monitoring
Treadmill Stress Tests
Ultrasound
Stress Test
Computerized Tomography (CT)
Positron Emission Tomography (PET)
Nuclear Medicine
Diagnostic Radiology
Angiography
Magnetic Resonance Imaging (MRI)
 EKG (Electrocardiogram)
These studies that record the changes of electrical potential occurring during the heartbeat, used especially in diagnosing abnormalities of heart action. EKG studies include Pediatric EKG, Signal-Averaged EKG, Routine Treadmill EKG and Holter Monitor Studies.
Echocardiography (Echocardiogram)
These studies that take "moving pictures" of the heart with sound waves. A more recent development uses electromechanical or electronic techniques to scan the ultrasound beam rapidly across the heart to produce two-dimensional images of selected sections of the heart. The types of echo studies include:
- Two-Dimensional
- M-Mode
- Pulsed Wave, Continuous Wave and Color Flow Doppler
- Transesophageal Echo: Biplane and Multiplane
- Exercise Stress Echo
- Dobutamine Stress Echo (Pharmacological Stress Echo)
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Holter monitoring is also known as ambulatory electrocardiography, ambulatory ECG or ambulatory EKG. In it, a patient wears a small recorder called a Holter monitor as he or she goes about normal daily life. The machine makes a graphic record of the heart's electrical currents.
Ambulatory EKG is mainly used to document and describe abnormal electrical activity in the heart. This can be random, spontaneous, sleep-related or caused by emotion or stress. Capturing and relating symptoms with rhythm disturbances (changes in the normal electrical pattern of the electrocardiogram) during activity requires recording or observing the heart's electrical activity during that time. This must be done continuously over time as a person goes about normal daily activities.
There are two basic types of recording devices. Continuous recorders are most often used for 24-48 hours. Intermittent recorders are used for weeks to months to provide brief, intermittent recordings.
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A Treadmill Stress Test records the heart's electrical activity (rate and rhythm) during exercise. During the test, the cardiologist and a technician are present. Electrodes are placed on the chest in the same manner as they are for an electrocardiogram (EKG). The patient will then be asked to walk on a motorized treadmill. The speed and incline of the treadmill will be gradually increased. The doctor will be looking for changes in the EKG pattern and any symptoms that the patient may experience. The patient may be on the treadmill for up to 15 minutes, depending upon his level of recovery and cardiovascular conditioning. The test will be stopped if the patient becomes too tired, has any symptoms such as chest pain. The test will last about 30 minutes. This test must be ordered by a doctor.
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Ultrasound scanning works like underwater sonar using a device similar to a microphone pressed against the area being scanned. Most ultrasound scans are done from outside the body, through the skin. This device sends out very high frequency sound waves, which go into the area being examined and bounce back when they hit an organ or blood vessel. These sound waves are processed by a computer, which produces a map of the area being scanned. This technique allows the radiographer to see static structures and to observe moving parts such as the heart of a baby in the womb or the valves inside an adult heart.
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Stress Test — studies that show how a patient's heart responds to an increased heart rate. Types of stress tests include:
Exercise Myocardial Perfusion Stress Test — a radioactive isotope that illuminates the vessels is injected and the patient walks on a treadmill until a target heart rate is reached. Scans are taken before and after the exercise to determine changes in the heart's activity.
Dobutamine Myocardial Perfusion Stress Test and Persantine Myocardial Perfusion Stress Test — Similar to the Exercise Stress Test except that drugs — dobutamine or persantine — rather than treadmill exercise are used to effect heart rate.
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 Computerized tomography, sometimes called CT scan or CAT scan, uses special X-ray equipment to obtain image data from difference angles around the body. A computer then processes these images to show multiple cross-sections of the tissue and organs. CT imaging is particularly useful because it can show several types of tissues — lungs, bones, soft tissue and blood vessels — with great clarity. With the amount of detail shown on CT scans, radiologists can more easily diagnose cancers, cardiovascular disease, infectious disease, trauma, and muscle and skeletal disorders. CT exams are used to plan and administer radiation treatments for tumors, guide biopsies, and plan surgery. CT images are also used to measure bone density for the detection of osteoporosis. Calcium scoring of the heart is another proactive use of the CT scan. CT scans play a significant role in the early detection, diagnosis and treatment of cancers and heart disease.
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 Positron Emission Tomography (PET) is a diagnostic tool that uses radioisotopes to image the body's biochemical functions, detecting the presence, recurrence or spread of various types of cancer. Certain subtle changes in the body's biochemistry are indications of different types of cancers, including but not limited to colon cancer, breast cancer, lymphoma, lung cancer, and melanoma. PET scans go beyond the scope of MRI and CT images to reveal the disease process before visible signs and symptoms may occur. PET is also being utilized as a tool to identify early stage heart disease and brain disorders.
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Nuclear medicine includes diagnostic examinations that result in images of body anatomy and function. These images result from detection of energy emitted from harmless radioactive substances given to the patient, either intravenously or by mouth. Nuclear medicine images assist physicians in diagnosing diseases, tumors and infections. Specifically, nuclear medicine can be used to analyze kidney function; show blood flow and functions of the heart; scan lungs for respiratory and blood-flow problems; identify blockage of the gallbladder; evaluate bones for fracture, infection, arthritis or tumor; determine the presence or spread of cancer; identify bleeding into the bowel; locate the presence of infection; and measure thyroid function to detect an overactive or underactive thyroid gland.
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Diagnostic radiology, more familiarly known as X-ray, is the oldest form of medical imaging. X-ray is a fast, painless, and safe way for a doctor to view and assess conditions ranging from broken bones to pneumonia to cancer. More specifically, X-rays may be used to determine whether a bone is chipped, dislocated, or broken; evaluate joint injuries and bone infections; diagnose and monitor the progression of degenerative conditions such as arthritis and osteoporosis; screen for heart and lung diseases; find and treat artery blockages; diagnose the cause of persistent coughing or chest pain; evaluate unexplained abdominal pain; help locate objects that may have been accidentally swallowed by a child; determine whether a bone or disk in the spine has been injured; detect scoliosis and other spinal defects; evaluate sinus infections; locate dental problems; diagnose lung, intestinal; stomach, liver, spleen, kidney, and breast cancer; and determine whether cancer has spread to the lungs from another part of the body.
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Angiograms are X-ray pictures of blood vessels. A long, slim, flexible tube called a catheter is used to place dye in an artery, then X-rays are taken to find any circulatory problems such as narrowing, leaking, misshaping, enlargement, or blockage. The most common types of angiograms include carotid, coronary, abdominal aortic, and aorto-femoral. Carotid angiograms exhibit the carotid arteries to the brain to show if stroke is likely due to blockage or narrowing, and may show a tumor of the brain, or an aneurysm — a weakened, bulging area in the artery wall. Coronary angiograms show the arteries feeding the heart. Abdominal aortic angiograms illuminate the large artery between the heart and the rest of the body. Aorto-femoral angiograms can show narrowing of the arteries to the legs, which may cause pain when walking.
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MRI is a diagnostic technique that uses a magnetic field and radio waves to create cross-sectional images of the head and body. MRI images are used in the diagnosis of central nervous system disorders as well as joint, ligament, muscle, and bone problems. Organ function, blood flow, presence of growths or lesions, and abnormal size or position of organs, bones, blood vessels or soft tissue structures are all analyzed by the radiologist evaluating the MRI images. Identifying damage caused by heart attack or heart disease and detection of plaque and blockages in the blood vessels are just a few examples of what the MRI reveals.
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