Rural and Remote Health Journal: Original research
Particularities of ST-Segment Elevation Acute Myocardial Infarction
Cases in Rural Transylvania, Romania
Deak E., Brumboiu I., Ţigan St., Bocşan I. S.
Authors address:
1
Eva Deac, MD, deak_eva62@yahoo.com
2
Irina Brumboiu*, PhD, associate professor of Epidemiology, ibrumboiu@umfcluj.ro
3
Stefan Ţigan, professor of informatics, stigan@umfcluj.ro
4
Ioan Stelian Bocşan, PhD, professor of Epidemiology, head of Epidemiology and
Primary Health Care Department, isbocsan@umfcluj.ro
1
The Nicolae Stăncioiu Heart Institute, Cluj-Napoca, Romania
The Iuliu Haţieganu University of Medicine and Pharmacy, Cluj-Napoca, Romania.
2, 3, 4
Correspondance: * Irina Brumboiu, Iuliu Haţieganu University of Medicine and
Pharmacy , 8, V. Babes, RO 400012, Cluj-Napoca, Romania, ibrumboiu@umfcluj.ro.
Author contribution: Eva Deak: original concept, patients’ selection, data collection,
patients’ surveillance, contribution to drafts. Irina Brumboiu: literature review,
contributed to project design, data analysis, interpretation, draft. Stefan Ţigan: data
validation, data base, statistic, data analysis. Ioan Bocşan: conducted the research,
original concept, project design, interpretation, contribution to draft.
ABSTRACT
Introduction: The patients’ place of domicile influences cardiovascular risk factors
connected with environmental and behavioural exposure thus playing a role in disease
occurrence and evolution as well as in patient access to specialised medical services. Our
study aimed to identify the characteristics of patients with ST-segment elevation acute
myocardial infarction from the rural and urban area and to assess the emergency medical
care provided to them.
Methods: The characteristics and initial medical care of patients with ST-segment
elevation acute myocardial infarction (STEMI) were analysed prospectively in a sample
of patients who underwent primary percutaneous transluminal (PCT) coronary
angioplasty within the first 12 hours after the onset of thoracic pain in a specialised
cardiology service between November 2008 and February 2010.
Results: Our sample included 321 STEMI patients, out of whom 32.4% were from the
rural areas. Patients’ characteristics revealed the predominance of the male gender with
67.3% of patients (56.1%-78.5%) and a mean age of 62.9 years (between 27 and 85),
most male patients being in the 6th decade of life and most female patients in the 7th
decade. Rural female patients accounted for 32.7% of the cases (16.6%-48.8%) as
compared to 23.4% (11.6%-35.2%) patients from the urban area. This difference became
statistically significant after standardization. Specific emergency medical care in the form
1
of PCT coronary angioplasty was performed in only 4.8% (0.7%-8.9%) of rural patients,
thus delaying myocardial reperfusion.
Conclusions: The characteristics of STEMI patients from the rural area showed the
predominance of the male gender as well as a higher mean age and number of female
patients with STEMI compared to the urban area. The inappropriate access of rural
patients to highly specialised cardiology services is therefore obvious.
Key words: rural, STEMI, primary PCT coronary angioplasty
INTRODUCTION
The patients’ place of origin may favour specific environmental and behavioural
exposures that could become risk factors for severe cardiovascular pathology, such as
myocardial infarction.
Rural patients with severe pathology requiring emergency medical care have
limited access to specialised services.
In acute myocardial infarction, an emergency intervention for the rapid
reperfusion of the affected coronary vessel is required in order to restore myocardial
perfusion. According to currently available studies, immediate prognosis depends on
appropriate early interventions. (1, 2).
Primary percutaneous transluminal coronary angioplasty (primary PCT) with
stenting is the best method of reperfusion available as it provides efficient blood supply
to the infarct area. (3, 4, 5, 6).
Specialized care in the Transylvania area is mainly provided by the Nicolae
Stăncioiu Heart Institute, Cluj-Napoca, where a catheterisation laboratory is available 24
hours a day for seven days a week.
The aim of this paper was to compare the characteristics of patients from rural and
urban Transylvania and the emergency care they received after the onset of acute
myocardial infarction until coronary reperfusion with stenting in our cardiology unit.
METHODS
All patients with ST-segment elevation acute myocardial infarction (STEMI) who
were referred to the Nicolae Stăncioiu Heart Institute Cluj-Napoca between November
2008 and February 2010 were identified and followed-up prospectively in order to
identify their personal characteristics and the emergency medical care received after the
onset of the infarction. Patient selection criteria included diagnosed STEMI, patient’s or
patient’s relatives ability to provide information regarding the current AMI episode,
patient consent and primary PCI. Patients who failed to provide information regarding the
events that took place between the onset of pain and hospital admission, patients who
declined participation in the study as well as those who died within hours of hospital
admission before undergoing primary PCI, were not included in this study.
The time interval between the onset of pain and primary percutaneous transluminal
coronary angioplasty was calculated in minutes and included all the stages of medical
care that patients received. A chart for each selected case recorded the following: 1. date
and time of hospital admission; 2. age; 3. gender; 4. place of origin (rural or urban); 5.
education (primary school, secondary school, higher education); 6. diagnosis on
2
admission; 7. localization of the infarction (anterior or non-anterior wall myocardial
infarction); 8. date and time of pain onset; 9. time of emergency call; 10. time of
ambulance arrival; 11. time of arrival at the first hospital; 12. time of admission at the
Heart Institute; 13. time of angiography; 14. time of balloon inflation +/- stenting (7).
Time intervals in minutes were calculated from the onset of precordial pain to
treatment and the analysis of time intervals between different levels of medical care were
the object of another paper (7).
Statistical analysis compared patients from the rural and urban area using the
mean values of continuous variables and the proportions for discrete variables describing
patient characteristics and the duration of emergency medical care until admission to the
cardiology unit and mechanical coronary reperfusion (primary PCI). Direct
standardisation was used to control confusing factors generated by different personal
characteristics in the rural and urban population (8). The statistical significance was
measured using Student’s t test and z tests for comparing proportions and mean values,
respectively (8).
RESULTS
A number of 321 STEMI patients were included in our study over a 16-month
period between November 2008 and February 2010, accordingly to the above-mentioned
selection criteria.
Of all STEMI patients, 104 (32.4%; 95% CI: 27.4-37.9%) were from the rural
area (Table 1). According to the 2002 census, the rural population accounts for 43.7% of
the entire regional population (2.744.008 inhabitants). Therefore, the proportion of rural
patients was significantly (p<0.001) lower than that of urban patients, who represented
67.6% of our cases (95% CI: 62.1%-72.6%; p<0.001) (according to the 2002 census: 9).
Male patients with STEMI prevailed in both the rural (67.3%; 56.1%-78.5% CI)
and urban area (76.6%; 95% CI: 70.1%-83.2%), as well as overall in the entire sample
(73.8%; 95% CI: 68.6%-78.5%) (Table 1).
The prevalence of female patients with STEMI was of 32.7% in the rural area
(95% CI: 16.6%-48.8%; z=1.773; 0.10>p>0.05), which was 9.3% higher than in the
urban area where the female patients accounted for 23.4% of all patients although the
proportion of women is higher in the urban area: 51.9% as compared with 50.4% in the
rural area (p<0.001) (Table 1). Using direct standardization, if there were no gender
differences between the rural and urban area, the prevalence of female patients with
STEMI would be of 32.4% in the rural area and of 22.5% in the urban area. The
comparison of the two standardised proportions of cases in women from the rural and
urban area revealed a significant difference at a 1.899 value of the z test, which is very
close to the 1.960 reduced error corresponding to the p=0.05 threshold value of statistical
significance.
Higher mean ages were recorded in female (64.7 years) than in male patients
(58.7 years; p<0.005) and in rural (62.9 years) compared to urban patients (58.7 years;
p<0.005) (Table 2). No differences were noted between the mean age of female patients
from the rural and urban area. The same lack of statistical significance was found in male
patients with STEMI.
According to age groups, most rural cases occurred in the 6th decade in men and
th
the 7 decade in women (Figure 1). Male patients from the urban area showed the highest
3
distribution in the 6th decade while women had equally high prevalence in the 7th and 8th
decades. Given the regional distribution of the adult population, the highest occurrence of
cases corresponded to a decrease in the male population who were in the 6th decade of
life in both the rural and urban area (Figure 2). Although the prevalence of the female
population has the same distribution in the urban area, a significant increase was
registered in the rural area (up to 19%; p<0.005) in the 7th decade of life compared to
other decades (Figure 2).
Only 4.8% (p<0.002) of rural patients received emergency medical care within
the first 3 hours after onset of the infarction compared to 17.5% urban patients (Table 3).
Emergency medical care within 3-6 hours did not show statistically significant
differences in the rural and urban area. The 6-12 hour interval before reperfusion of the
coronary vessel recorded in more than a half (58%) of the rural patients generated a
higher total ischemia time (TIT) compared with urban patients.
DISCUSSION
The epidemiological approach to a severe cardiovascular pathology that
represents the leading cause of death in Romania allows patient characterisation as well
as the assessment of patient evolution and currently available healthcare services in order
to identify risk factors and take preventive measures at individual and community level.
(1, 10, 11).
The different characteristics of rural and urban patients support the hypothesis
that environmental or intrinsic biological factors influence acute myocardial infarction
and its immediate prognosis. The predominant occurrence of the event in male patients in
both the urban and rural area suggests that individual biological factors play a major role
in the infarction.
The higher mean age of STEMI patients in the rural area (overall as well as in the
two genders) compared to the urban area suggests the importance of environmental
factors in the occurrence of myocardial infarction given the context of an average life
span of 72.02 years (68.55 in men, 75.51 in women) in the urban population and of 70.08
years (66.35 in men, 74.2 in women) in the rural population (according to data from the
2002 census: 9). The involvement of environmental factors is also obvious given that the
mean ages of STEMI patients, which were higher in women than in men in both the rural
and urban area, correspond to the higher average life span registered in women (75.51
years in the urban area and 74.2 years in the rural area) than in men (68.55 years in the
urban area, 66.35 years in the rural area) according to the 2002 census (9).
The distribution according to age decades and place of origin differed in male and
female patients, thus indicating the role of intrinsic (personal) factors in the occurrence of
STEMI. The higher number of female patients in the rural area may be explained by the
higher percentage of rural women in the 7th decade of life.
Rapid reperfusion of the infarct area has major role in the prognosis of patients
with ST-segment elevation AMI (2, 12). In our study, an early intervention (within the
first 3 hours after the onset of AMI) was possible in only a small number of patients from
the rural area where more than half of the patients benefited from a late intervention (612 hours), which diminished their chances of a favourable evolution. This aspect, besides
the long distances, suggests that patients from the rural area have reduced access to a
specialised cardiology service and that the real occurrence of acute myocardial infarction
4
in the rural area may have been systematically underestimated as patients failed to be
diagnosed and treated in due time.
CONCLUSIONS
1. STEMI is a serious health issue in the rural area.
2. The delayed access of patients from the rural area to a specialized cardiology
service prolongs total ischemia time.
3. Although the higher number and age of female patients from the rural area as well
as the onset of STEMI in rural patients of both genders are currently difficult to explain,
the presence of such issues in the rural area requires immediate measures in the
healthcare field.
ACKNOWLEDGEMENTS
We thanks to the intervention team of the Heart Institute and to all people how work at
the Ambulance for their collaboration especially in identifying of patients.
REFERENCES
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fibrinolitic therapy in ST-segment-elevation myocardial infarction: bayesian
hierarchial meta-analyses of randomized controlled trials and observational
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myocardial infarction patients to percutaneous coronary intervention centers: a
decision analysis. Annals of Emergency Medicine, 2009; 53(2): 233-240.
3. Bainbridge D.: Does off-pump or minimally invasive coronary artery bypass
reduce mortality, morbidity, and resource utilization when compared with
percutaneous coronary intervention? A meta-analysis of randomized trials. J
Thorac Cardiovasc Surg, 2007; 133(3): 623-31.
4. Thielmann M.: Prognostic impact of previous percutaneous coronary intervention
in patients with diabetes mellitus and triple-vessel disease undergoing coronary
artery bypass surgery. J Thorac Cardiovasc Surg, 2007; 134(2): 470-6.
5. Vlaar PJ.: Impact of pretreatment with clopidogrel on initial patency and outcome
in patients treated with primary percutaneous coronary intervention for STsegment elevation myocardial infarction: a systematic review. Circulation, 2008;
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6. Wijeysundera HC.: Meta-analysis: effects of percutaneous coronary intervention
versus medical therapy on angina relief. Ann Intern Med , 2010; 152(6): 370-9.
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Percutaneous Coronary Intervention in Patients with ST-segment Elevation Acute
Myocardial Infarction from the Cluj Area. Applied Medical Informatics, 2010; 27
(3): 29-36.
8. Kirkwood B.R., Sterne C.A.: Standardization. In: B.R. Kirkwood, C. A. Sterne:
Medical statistics. Oxford: Blackwell Science, 2003; 263-272.
5
9. *** Recensământul populaţiei şi al locuinţelor: Populaţia; România, 2002; datele
recensământului
din
2002
[Romanian
Census
2002].
Available:
http://www.recensamant.ro/pagini/rezultate (Accesed 16 March 2011).
10. Roger V.: Epidemiology of myocardial infarction. The Medical Clinics of North
America, 2007; 91: 537-552.
11. Cardoso O.; Gender impact on in-hospital outcomes after percutaneous coronary
intervention. Int J Cardiol, 2009; 133(1): 106-9.
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percutaneous coronary intervention: a program evaluation; Canadian Medical
Association Journal, 2007; 176(13): 327-32.
Table 1. Distribution of ST-segment elevation acute myocardial infarction cases
according to gender and place of origin
Place
Gender
Number of Percentage (%)
95% CI
Population
of
cases
structure
origin
(%)
Rural
female
34
32.7
16.6-48.8
50.4
male
70
67.3
56.1-78.5
49.6
total
104
100
100
Urban
female
51
23.4
11.6-35.2
51.9
male
166
76.6
70.1-83.2
48.1
total
217
100
100
All
female
85
26.2
21.5-31.4
51.2
AMI
male
236
73.8
68.6-78.5
48.8
cases
total
321
100
100
Table 2. Age of patients with acute myocardial infarction according to place of origin and
gender.
Place of Gender
Mean age
Standard
p
Lowest-highest
origin
(years)
deviation
age (years)
Rural
female
66.1
13.2
p<0.05b
27-85
i
0.30 p 0.20
male
61.4
10.9
0.10 p 0.05 ii
40-83
d
total rural
62.9
11.7
p<0.005
27-85
Urban
female
63.7
13.9
p<0.005c
28-88
i
0.30 p 0.20
male
57.1
12.7
0.10 p 0.05 ii
24-88
d
total urban
58.7
12.9
p<0.005
24-88
Total
female
64.7
12,7
p<0.005a
27-88
a
male
58.2
12,2
p<0.005
24-88
total
59.9
12,6
24-88
6
Significance: a – female – male comparison for entire sample; b - female – male comparison in the rural
area; c – comparison of all rural and urban cases; I – rural-urban comparison of female cases; ii – rural-urban
comparison of male cases.
Table 3. Distribution of cases according to the interval in hours until intervention after
the onset of coronary ischemia and place of origin.
Interval
in hours
0-3
3-6
6-12
Total
Number of cases
rural
urban
5
38
39
97
60
82
104
217
Percentage (%; 95% CI)
rural
urban
4.8
0,7-8,9
17.5
12,5-22,5
37.2
27,9-46,5
44.5
39,8-49,2
58
48,5-67,5
38
31,6-44,4
100
100
-
percentage of cases (%)
Demographic structure of the STEMI cases
45
40
35
30
25
20
15
10
5
0
21-30
31-40
41-50
51-60
61-70
71-80
81-90
age groups (years)
Urban Male
Urban Female
Rural Male
Rural Female
Figure1. Distribution of STEMI cases according to age groups, gender and place of
origin.
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Demographic structure of the North-western Romania
population
percentage (%)
30
25
20
15
10
5
0
21-30
31-40
41-50
51-60
61-70
71-80
81-90
age groups (years)
Urban Male
Urban Female
Rural Male
Rural Female
Figure 2. Structure of the adult population (over 20 years) according to gender and place
of origin in the north-western area (according to the 2002 census: 9).
8