Unstable angina / non ST elevation myocardial infarction natural history, complications and prognosis
Unstable angina / NSTEMI Microchapters
Unstable angina / non ST elevation myocardial infarction natural history, complications and prognosis On the Web
Unstable angina/NSTEMI are signs of severe heart disease. Natural history is complicated by the development of arrhythmias and heart failure. In a study it was shown that 14% of the cases of unstable angina can progress to an MI. Sudden death is an infrequent sequel of both unstable angina and NSTEMI.
Natural History, Complications, and Prognosis
- Unstable angina/NSTEMI are signs of severe heart disease.
- Patients can present with a history of cardiopulmonary symptoms.
- 14% of the cases of unstable angina progress to an MI.
- If left untreated, the natural course of the disease can be complicated by arrhythmias and heart failure.
- Sudden death is an infrequent sequel.
- The incidence of ischemic complications and the risk of death in unstable angina pectoris is lower than that in patients with either non ST elevation myocardial infarction (NSTEMI) or that in patients with ST segment elevation myocardial infarction (STEMI) but higher than that in patients with chronic stable angina pectoris.
- Unstable angina can lead to:
List of Factors Affecting the Development and Complications of NSTEMI (In Alphabetical Order)
- Blood lipid levels
- Catecholamine levels (smoking, cocaine, stress)
- Degree of coronary vasoconstriction
- Endothelial function
- Extent of collaterals
- Extent of plaque rupture or erosion
- Inflammatory substrate
- Location of the culprit coronary lesion
- Microembolization and microvascular obstruction
- Stenosis morphology and severity
- Systemic factors
- Thrombotic factors
- In unstable angina adverse events tend to occur early after admission and can be predicted by clinical and EKG characteristics.
- The greater the magnitude and duration of EKG changes, the poorer the prognosis.
- ST depression on EKG at admission and the presence of transient ischemia predicting an increased risk of MI and subsequent death whereas normal EKG patterns are associated with a good outcome.
- 1 year MI or death rate in patients with new ST deviation (more than 1 mm from baseline) has been shown to be 11% compared to 6.8% in patients with isolated T-wave inversion.
- The most powerful predictors of MI and death include history of hypertension and presence of transient ischemia.
- Persistence of pain is also associated with an unfavorable outcome.
- Significant determinants of poor outcome include:
Prognosis in NSTEMI
- Cardiac troponin I is a very sensitive marker of degree of myocardial damage and provides a prognostic value in patients with NSTEMI.
- Elevated BNP concentration is associated with an increased risk of mortality and congestive heart failure among patients with NSTEMI.
- In case of NSTEMI treated non-invasively, elevated levels of high sensitivity troponin T, N-terminal pro-brain natriuretic peptide (NT-proBNP) and growth differentiation factor 15 (GDF-15) are independently associated with an increased risk of myocardial infarction, stroke, and cardiovascular death.
- In contrast, among patients with NSTEMI treated invasively, elevated levels of only NT-proBNP and GDF-15 have been associated with an increased risk of subsequent myocardial infarction, stroke, and cardiovascular death.
- Morrow DA, de Lemos JA, Sabatine MS, Murphy SA, Demopoulos LA, DiBattiste PM; et al. (2003). "Evaluation of B-type natriuretic peptide for risk assessment in unstable angina/non-ST-elevation myocardial infarction: B-type natriuretic peptide and prognosis in TACTICS-TIMI 18". J Am Coll Cardiol. 41 (8): 1264–72. PMID 12706919.
- Wallentin L, Lindholm D, Siegbahn A, Wernroth L, Becker RC, Cannon CP; et al. (2014). "Biomarkers in Relation to the Effects of Ticagrelor in Comparison With Clopidogrel in Non-ST-Elevation Acute Coronary Syndrome Patients Managed With or Without In-Hospital Revascularization: A Substudy From the Prospective Randomized Platelet Inhibition and Patient Outcomes (PLATO) Trial". Circulation. 129 (3): 293–303. doi:10.1161/CIRCULATIONAHA.113.004420. PMID 24170388.