This study is retrospective in character and concerns the regional activities of the
Bielsko Emergency Medical Services and the possibility to send medical data electronically
from a patient’s location to the clinic of interventional cardiology (CIC) in Bielsko-Biała.
The study was conducted based on an ECG teletransmission system. The information used
is from Medical Response Team Intervention Report Cards completed by Medical Response
Centre managers. The following criteria were applied to limit the number of patients
participating in the study :
Study inclusion criteria:
patients with diagnosed myocardial infarction ST-ACS,
residents of the Medical Response Centre administrative area,
patients aged 20 or above, irrespective of gender,
Study exclusion criteria:
patients whose chest pain was of different origin than cardiac,
patients who were not diagnosed with ST-ACS,
patients who suffered sudden cardiac arrest during medical intervention,
patients transported to a different clinic of interventional cardiology not in Bielsko-Biała,
The patients in the study group were divided into two sub-groups. Group A (n=237)
included patients in whom the Medical Response Team confirmed an ST-ACS and carried
out an ECG with data teletransmission to the CIC. Group B (n=101) included patients
in whom the Medical Response Team confirmed an ST-ACS and carried out an ECG without
teletransmission. For both groups and for all patients, the Medical Response Team
recorded the time of arrival at the patient’s location and the time when the patient
was handed over to the CIC. The next stage of the study recorded the time t [mins] required for decisions on diagnostics, treatment and transport of patients with myocardial
infarction, and the time difference between the time of arrival of the MRT at the
patient’s location and the time the patient was handed over to the CIC. The distance
s [kms] from the patient’s place of residence to the CSC was calculated based on the geographical coordinates
(GPS) of the two points.
To prove the assumed research aim, statistical analysis of the data was conducted
to define the effectiveness of using teletransmission in relation to time t [mins],
to determine the influence of time t [mins] of the patient’s place of residence within the Bielsko-Biała city boundaries or the
Bielsko district, taking into account the distance s [kms].
Research into the effect of the time of day or night on the time t [mins] did not demonstrate a statistically significant dependence.
Statistical analysis of the data was conducted using the STATISTICA software package,
licence no. JPZP602D415110AR-9.
The selection of statistical analysis method was based on qualitative and quantitative
variable types and on ordinal and interval scale types, as well as compatibility of
distributions with normal distributions and skewness and kurtosis values. For the
qualitative variables, that is place of residence, non-parametric tests were used.
Their mutual dependencies were verified by chi-square independence tests. Verification
of the dependencies of interval scale type variables, i.e. route and time taken, on
category factors, i.e. location and time of day, were conducted using variance analysis
wherever the assumptions required by this analysis were fulfilled. The required variance
homogeneity was checked using the Levene test. The normality of distribution was verified
using the Kołmogorow-Smirnow test. For significant principal effects and interactions, the Tukey
HSD test was used for post hoc analysis. The effects of disturbing factors were verified
using covariance analysis. If the required assumptions were not met, Kruskal-Wallis
rank variance analysis was used. In all tests, the result was taken as significant