To perform the test, a small amount of radioactive substance is injected through an intravenous line into a vein in the arm or hand. Once the substance is absorbed, the patient lies on a table for a series of scans. The scan is often performed with a technology called single-photon emission computerized tomography, or SPECT. Images are sent to a computer to create 3-D images.
Coronary angiogram: This procedure is considered when blood and ECG test results indicate an urgent problem with the blood vessels that feed the heart, known as coronary arteries. A short tube is inserted into the blood vessel in the groin. Using X-ray images as a guide, a doctor inserts a catheter through the tube to reach the heart and coronary arteries. The coronary angiogram can pinpoint blockages in the arteries and show how much blood flow is blocked.
If needed, the physician can immediately open up the arteries or repair or replace damaged heart valves, eliminating the need for open-chest surgery. Cardiac computerized tomography CT : This scan shows the size and function of the heart muscle and can reveal valve problems. Once you're at the hospital, it's likely that your medical evaluation will move quickly.
Based on results from an electrocardiogram ECG and blood tests, your health care provider may be able to quickly determine if you are having a heart attack — or give you another explanation for your symptoms. You'll probably have a number of questions at this point.
If you haven't received the following information, you may want to ask:. Chest pain care at Mayo Clinic. Mayo Clinic does not endorse companies or products. Advertising revenue supports our not-for-profit mission. Check out these best-sellers and special offers on books and newsletters from Mayo Clinic Press. This content does not have an English version. This content does not have an Arabic version. Diagnosis Chest pain doesn't always signal a heart attack. Furthermore, variation may be explained by the limited information on health-related outcomes in this stable, undiagnosed population, and there is little consensus about which test is preferable, or even when one is required 7 - 9.
Major U. Furthermore, both U. To address these issues systematically, 2 large multicenter, open-label, randomized controlled trials explored the diagnostic evaluation of patients with symptoms that may represent coronary heart disease CHD. Each examined the potential role of coronary computed tomography angiography CCTA. However, several salient differences in study populations and endpoints are critical to understanding the implications of each. This review thus aims to provide a context for approaching non-noninvasive imaging by:.
Describing the historically unmet clinical need for outcomes research in cardiovascular imaging;. Despite the routine use of noninvasive testing for patients with stable chest pain of suspected cardiac etiology over the last several decades, until , no large-scale randomized trials had evaluated the diagnosis, management, and outcomes of these patients.
Most recent clinical trials for CCTA focused on assessing its accuracy and comparability for identification of CHD 16 , 17 , or its effect on management of low-risk patients presenting to the emergency department with acute chest pain However, few if any randomized studies directly compared the various anatomic and functional testing options in patients with stable chest pain using clinical endpoints.
In , Fryback and Thornbury devised hierarchical levels of diagnostic test evidence This commonly-cited model for efficacy in imaging describes 6 hierarchical tiers of evidence: 1 technical efficacy; 2 diagnostic accuracy; 3 diagnostic thinking; 4 therapeutic efficacy; 5 patient outcomes; and 6 societal efficacy, including cost-effectiveness. Recent randomized trials have assessed the impact of CCTA versus usual care among patients with suspected acute coronary syndromes in the emergency department, primarily with safety 21 , hospital length-of-stay 18 , and cost-effectiveness 22 endpoints, and are not included in this review.
Their results may also now be critically evaluated in the context of this model Figure 1. The left-hand column shows the Fryback and Thornbury model for assessing diagnostic test evidence on the basis of hierarchical levels of clinical outcomes The findings of both trials are summarized in subsequent columns, providing a comparison of the types of evidence provided by each, as well as the results.
The trial used an upstream primary endpoint related to diagnostic thinking, certainty of the attribution of symptoms to CAD, which showed an increase in the CCTA group relative risk: 1. The clinical outcomes-related secondary endpoint of the rate of cardiovascular death or myocardial infarction MI appeared to be reduced in the CCTA group at 20 months 0.
The event-related composite primary endpoint death, MI, hospitalization for unstable angina, or major CV procedural complication occurred at similar rates in the CCTA and functional testing groups 3.
More patients in the CCTA group underwent cardiac catheterization within 90 days after randomization Furthermore, among patients randomized to an intended nuclear test strata, the mean cumulative radiation exposure was lower in the CCTA group compared with the functional testing group This included all downstream radiation within 90 days, including that associated with cardiac catheterization, and is particularly intriguing, since more CCTA patients received cardiac catheterization.
First, both trials recruited symptomatic patients requiring nonemergent evaluation. Consistent with this, nearly half of the patients in both trials received aspirin and statin therapy at baseline. Thirdly, the interventions in both trials were similar: a comparison of CCTA to usual care early in the evaluation of patients with suspected CHD. Both trials followed patients for up to 4 years median 20 to 25 months and had low rates of adverse events attributable to CCTA which, when they did occur, were mild and self-limiting.
Fourthly, event rates in both trials were low, with large proportions of patients having normal or near normal coronary arteries and already receiving excellent preventative therapy at baseline.
Although CCTA did not improve the primary endpoint in PROMISE all-cause death, nonfatal MI, hospitalization for unstable angina, and major procedural complications , its use in both trials was associated with lower MI rates that were of borderline statistical significance. It is widely recognized that clinical outcomes, rather than surrogates, should be the standard for cardiovascular trials.
However, the event rates in both trials show that hard endpoints are challenging to meet in this low-risk population. However, the importance of the PROMISE findings must be also be considered in the context of the large patient population and pragmatic design reflecting contemporary clinical practice. Thirdly, the trial populations were distinct. PROMISE participants were slightly older, included more women, and had higher rates of cardiovascular risk factors at baseline, especially hypertension and diabetes mellitus.
Finally, the 2 trials had markedly different primary and secondary endpoints. However, both trials assessed a variety of measures of test outcomes along the same hierarchical continuum of diagnostic test performance 19 Figure 1. They also confirm findings from prior observational studies of high rates of nonobstructive CAD on invasive angiography, which may speak to the difficulty of clinical assessment, including the crucial step of patient selection for invasive testing The studies also corroborate several reports showing that more than two-thirds of noninvasive tests performed in patients with stable chest pain of suspected ischemic etiology are normal or that show nonobstructive CAD disease, and that many of these patients will not experience an untoward clinical event 24 - However, only an anatomic approach can identify nonobstructive disease, which is associated with event rates similar to obstructive, single-vessel disease Finally, both trials demonstrate that both anatomic and functional strategies resulted in few safety endpoints related to either testing arm or downstream events, such as cardiac catheterization, and relatively low levels of radiation exposure.
These findings are important, given recent concerns about inappropriate cardiac testing to prevent unnecessary risk to patients 2 , 28 , Stress testing will continue to play an important and highly appropriate frontline role in our assessment of stable, symptomatic patients. However, despite widespread adaptation into practice, stress testing had not previously undergone the same rigorous assessment for determining the impact of a diagnostic test on downstream clinical endpoints that both stress testing and CCTA have now undergone with these 2 trials.
Both strategies resulted in acceptable if not excellent outcomes for our patients. In stable ischemic heart disease, the symptoms tend to worsen over time, meaning that they arise at lower levels of exercise and are more severe.
This usually takes months or years to develop. Localization of pain Where is the pain located? Diffuse or distinct location? Pain radiating to the left? More severe on the left side? Ischemic heart disease typically causes diffuse pain over a wide area of the anterior chest wall the pain is not localized.
Ischemic heart disease also tends to cause pain radiating to the left arm, neck, shoulder or jaw. Patients typically report that the pain is more severe on the left side of the chest.
Ischemic chest pain is usually described as pressure, squeezing, or a crushing sensation across the precordium and may radiate to the neck, shoulder, jaw, back, upper abdomen, left or right arm. Associated symptoms Pain radiation to arm, neck, jaw or back? Cold sweats? Nausea or vomiting? Ischemic chest pain causes symptoms from the autonomic nervous system, most notably diaphoresis sweating , nausea, and vomiting. Dyspnea suggests either a cardiac or pulmonary etiology. Palpitations suggest either a cardiac or pulmonary etiology.
Alleviating factors Pain alleviated by rest? Pain alleviated by nitroglycerin? Ischemic chest pain is typically alleviated by rest and by administration of nitroglycerin. However, these characteristics are not specific to ischemic chest pain. Frequency of symptoms How many episodes of chest pain? Time of the latest episode? Myocardial infarction occurs after 20 minutes of severe ischemia.
It may take up to 6 hours for troponin levels to increase significantly after myocardial infarction, which is why troponin results are not conclusive before 6 hours after the last episode of pain. Thus, if 6 hours have passed since the last episode of pain, the troponin tests will be able to determine whether the patient developed myocardial infarction.
Other Recent infections particularly airway infection? Chest trauma? Heavy physical exertion? All these suggest non-ischemic causes. Alarming signs Severe pain. Affected general appearance.
Morphine-resistant pain. Diabetics, elderly and women. Pulmonary edema. Severe pain increases the likelihood of serious etiologies. Morphine-resistant pain suggests serious etiologies. Diabetics, elderly and women may have atypical symptoms, which is why angina equivalents dyspnoea, sweating, extreme fatigue, atypical pain must be assessed. In elderly dyspnoea is as common as angina in acute myocardial infarction. Note that epigastralgia may be caused by inferior myocardial infarction.
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