Unstable angina / non ST elevation myocardial infarction cardiovascular syndrome x
 |
Resident Survival Guide |
|
Unstable angina / NSTEMI Microchapters |
|
Differentiating Unstable Angina/Non-ST Elevation Myocardial Infarction from other Disorders |
|
Special Groups |
|
Diagnosis |
|
Laboratory Findings |
|
Treatment |
|
Antitplatelet Therapy |
|
Additional Management Considerations for Antiplatelet and Anticoagulant Therapy |
|
Risk Stratification Before Discharge for Patients With an Ischemia-Guided Strategy of NSTE-ACS |
|
Mechanical Reperfusion |
|
Discharge Care |
|
Case Studies |
|
Unstable angina / non ST elevation myocardial infarction cardiovascular syndrome x On the Web |
|
FDA on Unstable angina / non ST elevation myocardial infarction cardiovascular syndrome x |
|
CDC onUnstable angina / non ST elevation myocardial infarction cardiovascular syndrome x |
|
Unstable angina / non ST elevation myocardial infarction cardiovascular syndrome x in the news |
|
Blogs on Unstable angina / non ST elevation myocardial infarction cardiovascular syndrome x |
Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1]; Associate Editor-In-Chief: Smita Kohli, M.D.
Overview
Cardiovascular syndrome X refers to patients with angina or angina-like discomfort with exercise, ST-segment depression on exercise testing, and normal or nonobstructed coronary arteries on angiography. This entity should be differentiated from the metabolic syndrome X or metabolic syndrome, which describes patients with insulin resistance, hyperinsulinemia, dyslipidemia, hypertension, and abdominal obesity. It also should be differentiated from noncardiac chest pain.
Cardiovascular Syndrome X in UA / NSTEMI
- Syndrome X is more common in women than in men.
- The cause of the discomfort and ST-segment depression in patients with syndrome X is not well understood. The most frequently proposed causes are:
- Impaired endothelium dependent arterial vasodilatation with decreased nitric oxide production,
- Impaired microvascular dilation (non-endothelium-dependent),
- Increased sensitivity to sympathetic stimulation, or
- Coronary vasoconstriction in response to exercise.
- Recently, there is increasing evidence that these patients frequently also have an increased responsiveness to pain and an abnormality in pain perception.
Diagnosis
- The diagnosis of syndrome X is suggested by the triad of:
- This can be confirmed by provocative coronary angiographic testing with acetylcholine for coronary endothelium-dependent function and adenosine for non-endothelium-dependent microvascular function.
- Other non-cardiac causes of chest pain such as esophageal dysmotility, fibromyalgia, and costochondritis should be ruled out.
Treatment
- It is recommended that patients be reassured of the excellent intermediate-term prognosis and treated with long-acting nitrates.
- If the patient continues to have episodes of chest pain, a calcium channel blocker or beta blocker can be started.
- Beta blockers and calcium channel blockers have been found to be effective in reducing the number of episodes of chest discomfort. Nitrates can be helful in half of the patients.
- Imipramine, 50 mg daily has been successful in some chronic pain syndromes, including syndrome X, reducing the frequency of chest pain by 50%.[1]
- Transcutaneous electrical nerve stimulation and spinal cord stimulation can offer good pain control.
- Statin therapy and exercise training have improved exercise capacity, endothelial function, and symptoms in some studies.
2011 ACCF/AHA Focused Update Incorporated Into the ACC/AHA 2007 Guidelines for the Management of Patients With Unstable Angina/Non -ST-Elevation Myocardial Infarction (DO NOT EDIT)[2]
Cardiovascular “Syndrome X” (DO NOT EDIT)[2]
| Class I |
| "1. Medical therapy with nitrates, beta blockers, and calcium channel blockers, alone or in combination is recommended in patients with cardiovascular syndrome X. (Level of Evidence: B)" |
| "2. Risk factor reduction is recommended in patients with cardiovascular syndrome X. (Level of Evidence: B)" |
| Class III |
| "1. Medical therapy with nitrates, beta blockers, and calcium channel blockers for patients with non cardiac chest pain is not recommended. (Level of Evidence: C)" |
| Class IIb |
| "1. Intracoronary ultrasound to assess the extent of atherosclerosis and rule out missed obstructive lesions may be considered in patients with syndrome X. (Level of Evidence: B)" |
| "2. If no ECGs during chest pain are available and coronary spasm cannot be ruled out, coronary angiography and provocative testing with acetylcholine, adenosine, or methacholine and 24 h ambulatory ECG may be considered. (Level of Evidence: C)" |
| "3. If coronary angiography is performed and does not reveal a cause of chest discomfort, and if syndrome X is suspected, invasive physiological assessment (i.e., coronary flow reserve measurement) may be considered. (Level of Evidence: C)" |
| "4. Imipramine or aminophylline may be considered in patients with syndrome X for continued pain despite implementation of Class I measures. (Level of Evidence: C)" |
| "5. Transcutaneous electrical nerve stimulation and spinal cord stimulation for continued pain despite the implementation of Class I measures may be considered for patients with syndrome X. (Level of Evidence: B)" |
References
- ↑ Cannon RO, Quyyumi AA, Mincemoyer R; et al. (1994). "Imipramine in patients with chest pain despite normal coronary angiograms". N. Engl. J. Med. 330 (20): 1411–7. PMID 8159194. Unknown parameter
|month=ignored (help) - ↑ 2.0 2.1 Anderson JL, Adams CD, Antman EM, Bridges CR, Califf RM, Casey DE; et al. (2011). "2011 ACCF/AHA Focused Update Incorporated Into the ACC/AHA 2007 Guidelines for the Management of Patients With Unstable Angina/Non-ST-Elevation Myocardial Infarction: a report of the American College of Cardiology Foundation/American Heart Association Task Force on Practice Guidelines". Circulation. 123 (18): e426–579. doi:10.1161/CIR.0b013e318212bb8b. PMID 21444888.