Abstract
The electrocardiogram (ECG) is the primary tool in the diagnosis of acute myocardial
infarction (AMI). However, other clinical conditions, both cardiac and noncardiac
originated pathologies, may result in ECG tracing of AMI. This may lead to an incorrect
diagnosis, exposing the patients to unnecessary tests and potentially harmful therapeutic
procedures. The aim of this report is to increase the still insufficient awareness
of clinicians from multiple disciplines, regarding the different clinical syndromes,
both cardiac and noncardiac, associated with ECG abnormalities mimicking AMI, to avoid
unjustified thrombolytic therapy or intervention procedures. During a 9-year period,
the data from six patients (five females, one male; mean age, 50 years [range, 18
to 78 years]) who were admitted to cardiac care unit (CCU) with transient ECG changes
resembling AMI were recorded retrospectively. During this 9-year period, 5,400 patients
were hospitalized in CCU: 1,350 patients were diagnosed as ST-elevation myocardial
infarction (STEMI) and 4,050 patients were diagnosed as non-ST-elevation myocardial
infarction (NSTEMI). Only two out of six patients had chest pain with ECG changes
criteria suspicious of AMI. STEMI was suspected in four out of six patients. All patients,
but one, had normal left ventricular (LV) function. One patient had transient LV dysfunction.
All patients, but one, with perimyocarditis, had normal serum cardiac markers. In
four out of six patients, who underwent coronary arteries imaging during hospitalization
(by angiography or by CT scan), normal coronary arteries were documented. Two patients
who underwent ambulatory cardiac CT scan imaging after being discharged from hospital
documented patent coronary arteries (case no. 3), or some insignificant irregularities
(case no. 4). The discharge diagnoses from CCU were as follows: postictal syndrome,
pericarditis, hypothermia, stress-induced (“tako-tsubo”) cardiomyopathy, anaphylactic
reaction, and status of postchemotherapy. All patients experienced full recovery with
normal ECG tracing. During the 5-year follow-up, all patients were alive, and cardiac
morbidity was not reported. We conclude that both cardiac and noncardiac clinical
syndromes may mimic AMI. Comprehensive clinical examination and profound medical history
are crucial for making the correct diagnosis in conditions with ECG changes mimicking
AMI.
Keywords
ECG changes - mimicking acute MI - clinical conditions - cardiac and noncardiac -
normal coronary arteries
