With 20,000 echocardiograms performed each year, the Montefiore Einstein Center for Heart and Vascular's cardiac imaging program is among the largest in New York City. As a premier urban cardiac imaging center, the Heart and Vascular Center uses only state-of-the-art digital equipment that results in clearer images that are more easily accessed by doctors working remotely.
Surgeons are provided a three-dimensional picture of the arteries running along the surface of the heart by using baseline images provided by echocardiograph and CT angiography. This cutting-edge technology makes noninvasive diagnoses of a range of heart problems possible.
The Heart and Vascular Center's Cardiac Imaging Center is built on a solid foundation of four standard imaging procedures:
The echocardiograph, or echo, is a noninvasive test that provides cardiologists with a survey of the heart using the same ultrasound technology used for pregnant women. The echo allows cardiologists to examine the size of a patient's heart and the condition of the patient's valves to determine how efficiently the heart contracts. Echos also reveal common congenital problems and possible causes for murmurs, palpitations, chest pain and shortness of breath.
An echo is performed by a technician called a sonographer, who spreads a gel over the chest to make sure that the ultrasound camera maintains good contact with the skin. During the exam, the sonographer will take still pictures of the heart, record video of the heart beating, and examine the direction of blood flow. Based on the results of this 20- to 30-minute test, cardiologists determine if more invasive tests are needed.
While the regular echo gives the cardiologist a picture of the heart at rest, the stress echo gives the cardiologist a picture of the heart after the patient has been exercising on a treadmill. By comparing a stress echo to an at-rest echo, the cardiologist may catch problems that surface only when the heart is under strain. Roughly 95 percent of stress echos are done to look for evidence of blocked arteries in patients who are experiencing chest pain, shortness of breath or palpitations.
For patients who are unable to walk on the treadmill due to disability or lung problems, the stress echo can be done with Dobutamine, a drug that that increases the heart rate without exercise.
Nuclear Stress Test
The nuclear stress test and the stress echo both test the condition of the heart under strain. However, if a patient is unable to exercise and is unable to take Dobutamine because of an arrhythmia (irregular heartbeat), the nuclear stress test can use adenosine instead of Dobutamine. In some cases, the nuclear stress test offers a clearer image. However, the procedure takes much longer than a traditional stress test, and results aren't immediately available because they must be processed by a technician before the cardiologist can view them.
Unlike an echo, which is done from outside the body, transesophageal echocardiography (TEE) is performed with a probe inserted into the esophagus. The picture available through the esophagus is much clearer than a traditional echo because there is less skin, bone and muscle to navigate. For example, a physician can't view the aorta on a traditional echo, yet a surgeon can view a clear picture of the aorta with TEE.
Cardiologists in the imaging center meet regularly with radiologists to discuss improved techniques for imaging the heart. Because of such interdisciplinary cooperation, the imaging center has access to cutting-edge technologies such as:
Multislice Computed Tomography Angiography
Computed tomography (CT) is the first test to give doctors a truly three-dimensional picture of how a patient's coronary arteries run along the surface of the heart. This test is the latest advance in the effort to map blockages in coronary arteries.
With a stress echo, a cardiologist is able to make an educated guess about the existence of a blocked artery based on how the heart responds to exercise. When a block is suspected, cardiologists generally recommend that patients receive an angiogram, an invasive test that probes the coronary arteries. But CT angiography gives cardiologists a clear picture of the actual block. Eventually, this cutting-edge improvement may reduce the number of patients who need invasive testing, such as an angiogram.
Cardiac Magnetic Resonance Imaging
Cardiac magnetic resonance imaging (MRI) is used to search for tearing and aneurysm, or bulging of the aorta. MRI is an effective tool for mapping the overall heart structure of patients with congenital heart problems. For patients who are potential candidates for coronary artery bypass surgery or angioplasty, MRI can guide cardiologists to healthy heart tissue. This helps determine if overall function will improve if procedures to increase blood flow to the heart are performed.