J Korean Soc Emerg Med.  2005 Oct;16(5):511-518.

Impacts of Pain on Clinical Features and Outcomes in Patients Presenting to the Emergency Department with Acute Myocardial Infarction

• Kim H
• Lee SW

Abstract

PURPOSE
Myocardial infarction (MI) can be diagnosed and evaluated by clinical, electocardiographic, biochemical, radiologic, and pathologic methods. Traditionally the diagnosis of acute MI has been based on the triad of ischemic chest discomfort, ECG abnormalities, and elevated serum cardiac markers. However, not all patients with acute MI present with chest pain, and the extent of acute MI without pain is not well known. The aim of this study is to seek clinical features, risk factors, and outcomes in patients with painless MI as compared with painful MI.
METHODS
We reviewed the medical records of patients with acute MI who had presented to the Emergency Department (ED) at Chungbuk University Hospital between June 2002 to May 2005, and we analyzed the clinical and the radiological data, which included the patient's age and gender, the duration of hospital stay, the vital signs, cardiac markers, angiographic findings, echocardiographic findings, etc, and we compared painless MI with painful MI.
RESULTS
Of a total of 372 patients presenting to the ED with MI, 30 patients (8.1%) presented with painless MI, and the most common chief complaint was dyspnea, followed by fatigue and dzziness. Significant clinical factors associated with painless MI were the female gender, diabetes, hypertension, albuminuria, high serum glucose level, advanced age, extended arrival time to the ED, long time to EKG, and delayed thrombolytics or emergency percutaneous coronary intervention (PCI). The rate of congestive heart failure and the in-hospital mortality rate associated with painless MI were 46.7% and 20.0%, respectively, which were significantly higher rates than those for painful MI.
CONCLUSIONS
The higher mortality rates seen in patients with painless MI can be explained by the excessive rate of congestive heart failure (CHF), the delayed arrival at the ED, and the delayed diagnosis.

Keyword

Myocardial infarction; Emergenices; Heart failure; Congestive; Hospital mortality

MeSH Terms

Albuminuria
Blood Glucose
Chest Pain
Chungcheongbuk-do
Delayed Diagnosis
Diagnosis
Dyspnea
Echocardiography
Electrocardiography
Emergencies*
Emergency Service, Hospital*
Fatigue
Female
Heart Failure
Hospital Mortality
Humans
Hypertension
Length of Stay
Medical Records
Mortality
Myocardial Infarction*
Percutaneous Coronary Intervention
Risk Factors
Thorax
Vital Signs