Sensitivity and specificity of echocardiographic identification of patients eligible for safe early discharge after acute myocardial infarction.
In a prospective clinical trial of 195 consecutive unselected patients with acute myocardial infarction (AMI), systematic blinded clinical and echocardiographic examinations were performed by two observers on day 5. The purpose was to define low-risk patients with regard to in-hospital and 2-month mortality and predict the potential costs (lost patient lives) and benefits (saved in-patient days) if as a routine procedure these low-risk patients were discharged earlier. By design, low-risk patients as defined by clinical criteria were allocated to discharge on days 7 to 10 and by echocardiographic criteria on days 5 to 7 after AMI. The sensitivity of the echocardiographic low-risk identification procedure was more than twofold higher than the sensitivity of clinical low-risk identification (49% vs 24%). Both procedures were safe with a specificity of 100% for cardiac mortality. Optimal identification of low-risk patients was provided by combining data from echocardiographic and clinical evaluations (sensitivity 59%). Results of the study suggest that a bedside echocardiographic approach to estimation of global left ventricular function is more sensitive and equally specific and therefore more efficient for risk stratification on post-AMI day 5 than clinical examination alone. Thus echocardiographic examination allows identification of a larger subset of patients with AMI (greater than 40% of the population alive on day 5) who can be discharged earlier and safely, with a potential saving of in-patient days of 436 days in 87 low-risk patients minus the cost of echocardiographic studies in 195 patients. However, the best prediction was obtained by combining clinical and echocardiographic examination.(ABSTRACT TRUNCATED AT 250 WORDS)
Launbjerg
J
J
Medical Department B, Frederiksborg County Central Hospital, Hillerød, Denmark.
Berning
J
J
Fruergaard
P
P
Appleyard
M
M
D000368:Aged; D003718:Denmark / Q000453:epidemiology; D004452:Echocardiography; D005260:Female; D017052:Hospital Mortality; D006801:Humans; D008297:Male; D009203:Myocardial Infarction / Q000000981:diagnostic imaging* / Q000401:mortality*; D010351:Patient Discharge / Q000706:statistics & numerical data; D011379:Prognosis; D011446:Prospective Studies; D012307:Risk Factors; D012680:Sensitivity and Specificity; D013997:Time Factors