SPECT
SPECT or Single Photon Emission Computed Tomography is a diagnostic tool that that uses gamma camera to collect gamma rays that are emitted from the patient. Radioactive isotope is adminstered to the patient either as injection or inhalation or ingested liquid. SPECT imaging helps acquire multiple images from multiple angles. The gamma camera is rotated around the patient. Dual-headed cameras can help in accelerating the test. Often triple-headed cameras are also used. SPECT is particularly useful in imaging of tumors, bones, thyroid and infections. Cardial imaging and brain imaging provide critical information about localized functions. MPI (Myocardial perfusion imaging) is an important cardiac stress test. SPECT images allow diagnosis of ischemic heart disease. This test is comparable to stress echocardiography. SPECT imaging of the brain aids in distinguishing Alzheimer's disease from other vascular dementias. Nearly 30 or more images are taken of the specific body area that is being viewed. SPECT scanning is time consuming.
Sumatriptan
Sumatriptan, part of the family of drugs called as triptans is prescribed for the treatment of Migraine and cluster headaches. Migraine headaches are thought to be the result of dilation of blood vessels in the head. Sumatriptan causes constriction of the blood vessels thus relieving Migraine. Triptans are technically abortive migraine medications. However, Sumatriptan does not prevent or reduce the number of migraine attacks. There is another 'triptan' drug which has slightly less side effects than Sumatriptan - Rizatriptan.
Dosage and Administration: Starting dosage may be 25 mg or at the discretion of the physician. However, the Physician might want the patient to take the first dosage at his office to monitor any adverse heart events. Normal dosage is 25 mg to 100 mg or as prescribed by the Physician. Maximum dose in any 24 hours should not exceed 300 mg orally. Do not use Sumatriptan concomitantly with Ergotamine containing preparations.
Safety and efficacy has not been proved for patients over 65 years or for children.
Contraindications: The use of Sumatriptan is contraindicated in hypersensitivity, ischemic heart disease or previous myocardial infraction, Prinzmetal's angina, coronary vasospasm and controlled hyper tension. Sumatriptan should not be used unless there is a clear diagnosis of Migraine. Before use, exclude underlying cardiac disease especially in patients with risk factors. Chest symptoms may occur which mimic angina but are rarely found to be the result of vasospasm. Vasospasm may result in arrhythmia, ischemia or myocardial infarction. This drug is to be avoided for patients with impaired renal or hepatic functions.
Sumatriptan should not be administered along with ergot type migraine medications, or with MAO inhibitors. Sumatriptan and Ergotamine together can cause prolonged spasm of the blood vessels. It is essential that the use of these two medications should be separated by at least 24 hours.
Side Effects of Sumatriptan: Pain, tingling sensation, heaviness or pressure in the chest region which may be transient. Rarely severe flushing, dizziness, paresthesia, weakness, fatigue, drowsiness may occur. Transient rise in blood pressure may occur.
Stress echocardiography
Cardiac stress determination or stress echo is done to investigate underlying coronary artery disease. It helps determine blood flow and the pumping rate of the heart. The preliminary tests performed before stress echocardiography include the assessment of ventricular function, wall motion thickness and aortic root. These tests indicate cardiac conditions along with ischemic heart disease and other cardiac conditions. Stress echocardiography is recommended over pharmacological assessment, because of its advantage in describing the cardiac performance during the test through images. Pictures are taken of your heart before and after exercise to check the efficiency of the heart.
Stress echocardiography is carried out on a treadmill or by a bicycle in a supine position. A work load of 25W is given initially with subsequent rise in intensity. Stress echocardiography also determines the aerobic capacity. The use of bicycle exercise has an advantage as it gives the Doppler information of the test. This provides information about the blood flood through the heart's pumping chambers and valves. Stress echocardiography has been extensively used in the risk evaluation for coronary artery disease even in patients who are asymptomatic. The usual protocol followed for the test is fasting for at least three hours before the test is performed.
Before commencing the stress test, your blood pressure and electrocardiogram (EKG) is also done. The stress echo is taken during the rest phase, stress phase and a repeat when the heart is still beating fast. Pregnant women are not advised to undergo this test. You will be connected to an ECG monitor to record the heart activity through small electrodes. Stress echocardiography is beneficial for physicians to determine the treatment options for asymptomatic conditions pertaining to coronary artery disease. It also aids the detection of angina or chest pain in the patients and also conditions like cardiomegaly and myocardial infarction.
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