[The changing prognosis of myocardial infarction in the reperfusion era: implications for evaluation and management of ventricular arrhythmias].
The prognosis of patients with ischemic heart disease has improved markedly with the introduction of reperfusion therapy and with aggressive efforts to modify risk factors. Consequently, the rate of cardiovascular events after myocardial infarction has decreased to approximately 5% over a period of 2 years as compared with the 20% to 30% reported in the prethrombolytic era. In this context, it is unlikely that the results of previous studies in the prereperfusion era can be applied to this group of patients. Others have demonstrated that the identification of subgroups of patients at greater risk and the search for new risk markers can significantly improve survival of patients who are at high risk despite reperfusion therapy. For example, it was found in the GISSI-2 study that unsuitability for exercise stress testing was associated with a mortality of 7% at 6 months. Other factors that determine poor prognosis after myocardial infarction are transitory heart failure, left ventricular dysfunction, and advanced age. The active search for new risk markers has identified other factors such as nonresolution of ST-segment changes, impaired ventricular filling, anomalous baroreflex sensitivity, or T-wave alternans that may be of benefit in assessing risk. Also, the timing of risk stratification can be critical. Often, risk factors have been analyzed weeks or even months after infarction instead of before hospital discharge. Approximately 30% of patients have deterioration of left ventricular function in the next 2 or 3 months, whereas others have improvement, highlighting the difficulties in attempting to risk stratify at one point in time. Although nobody doubts the effect that coronary revascularization has had on the prognosis of ischemic heart disease or the effectiveness of aspirin, beta -blockers, lipid-lowering drugs, and angiotensin-converting enzyme inhibitors, the search for cardiac or noncardiac risk markers can contribute notably to increasing the survival of patients who have had myocardial infarction.
Gersh
Bernard J
BJ
Division of Cardiovascular Diseases and Internal Medicine. Mayo Clinic. Rochester. Minnesota. USA.
D001145:Arrhythmias, Cardiac / Q000473:pathology* / Q000503:physiopathology; D006352:Heart Ventricles / Q000503:physiopathology; D006801:Humans; D009203:Myocardial Infarction / Q000473:pathology* / Q000503:physiopathology; D015425:Myocardial Reperfusion; D011379:Prognosis