Vol.12, No 3, 2005 pp. 130 - 134
UC 616.379-008.64:616.127-005.8
IMPACT OF DIABETES ON HEART RATE
VARIABILITY AND LEFT VENTRICULAR FUNCTION IN PATIENTS AFTER MYOCARDIAL
INFARCTION
Viktor Stoičkov, Stevan Ilić, Marina Deljanin Ilić, Aleksandar
Nikolić, Vojislava Mitić
Institute for Prevention, Treatment and
Rehabilitation of Rheumatic and Cardiovascular Diseases "Niška Banja",
Niška Banja
E-mail: viktors@bankerinter.net
Summary.
Coronary patients with diabetes are at high risk of
cardiovascular events. Coronary disease in diabetic patients has a
rapid and
progressive course due to the synergic activity of hyperglycemia and
other risk
factors of coronary disease such as dyslipidemia, hypertension,
obesity, and
smoking. Diabetic autonomic neuropathy which first affects the vagal
nerves
contributes to the bad prognosis of coronary patients with diabetes.
The best
marker of the state of activity of the autonomic nervous system is
heart rate
variability, which is a predictor of cardiac mortality.
The aim of this study was to determine a possible
influence of diabetes mellitus on the left ventricular function and the
parameters of heart rate variability, as well as the relation between
the left
ventricular function and the parameters of heart rate variability in
patients
after myocardial infarction and diabetes.
We studied 141 patients after myocardial infarction in
the sinus rhythm without AV blocks or branch blocks. Thirty-five
patients had
diabetes mellitus, and 106 did not. The average age of the patients was
58.82
years. Besides clinical examination and laboratory analyses, standard
ECG,
exercise test on a treadmill according to Bruce protocol, 24-hour
holter
monitoring, and echocardiographic examination were performed in each
patient.
Based on the holter record, the analysis of the heart rate variability
was
performed by software. Four parameters of the time domain heart rate
variability were assessed: SDNN, SDANN, RMS-SD and NN > 50
ms.
Diabetic patients after myocardial infarction had a
significantly lower values of the monitored parameters of heart rate
variability, compared to those without diabetes
(89.47 ± 30.82 vs. 103.28 ± 32.18 ms;
p < 0.025 for SDNN; 28.50 ± 13.71 vs.
35.22 ± 12.42 ms; p<0.02 for
RMS-SD; 77.26 ± 27.58 vs. 88.74 ± 30.58 ms;
p < 0.05
for SDANN and 7.45 ± 8.63 vs. 11.07 ± 9.08 ms;
p < 0.05
for NN > 50 ms). Diabetics also had significantly lower values of
LVEF
(49.19 ± 8.01 vs. 52.84 ± 11.24 %;
p < 0.05) and
significantly higher values of LVESd (39.39 ± 4.82 vs.
37.03 ± 6.18 mm; p<0.025), as
well as a higher degree of the left ventricle diastolic dysfunction,
compared
to non-diabetics (0.82 ± 0.18 vs. 0.91 ± 0.21;
p<0.02 for ratio E/A and 183.52 ± 47.29
vs. 214.32 ± 46.15; p < 0.005 for Dt). The study
showed that there is a
significant positive correlation of SDNN values and SDANN with LVEF (r
= 0.510;
p < 0.01 for SDNN and r = 0.569; p < 0.01 for
SDANN)
and a significantly negative correlation with LVESd (r = -0.361;
p < 0.05
for SDNN and r = -0.364; p < 0.05 for SDANN), while
with LVEDd the correlation did not reach the level of significance in
diabetic
patients after myocardial infarction. The values of parameters RMS-SD
and NN > 50
ms did not correlate significantly with LVEF or the internal dimensions
of the
left ventricle in diabetics after myocardial infarction.
The
study demonstrated diabetic patients who suffered myocardial infarction
have
significantly lower values of the parameters of heart rate variability,
significantly lower values of LVEF and significantly higher values of
LVESd, as
well as a higher degree of the left ventricle diastolic dysfunction,
compared
to non-diabetics. The study showed that there is a significant positive
correlation of SDNN and SDANN values with LVEF and a significant
negative
correlation with LVESd in diabetics who suffered myocardial infarction.
Key words: Heart rate variability, left ventricle function,
myocardial infarction, diabetes mellitus
UTICAJ DIJABETESA NA VARIJABILNOST
FREKVENCIJE SRČANOG RADA I FUNKCIJU LEVE KOMORE U BOLESNIKA SA
PREŽIVELIM INFARKTOM MIOKARDA
Kratak sadržaj: Koronarni
bolesnici sa dijabetesom su na visokom riziku od kardiovaskularnih
događaja.
Koronarna bolest u dijabetičara ima ubrzan, progresivni tok usled
sinergističkog
delovanja hiperglikemije i drugih faktora rizika koronarne bolesti, kao
što su
dislipidemija, hipertenzija, gojaznost i pušenje. Lošoj prognozi
koronarnih
bolesnika sa dijabetesom doprinosi i dijebatesna autonomna neuropatija
koja
prvo zahvata parasimpatikus. Najbolji marker stanja aktivnosti
autonomnog
nervnog sistema je varijabilnost frekvencije srčanog rada, koja je
nezavisni
prediktor kardijalnog mortaliteta.
Cilj rada je da se utvrdi
uticaj dijabetes melitusa na funkciju leve komore i parametre
varijabilnosti
frekvencije srčanog rada, kao i odnos funkcije leve komore i parametara
varijabilnosti frekvencije srčanog rada kod bolesnika sa preživelim
infarktom
miokarda i dijabetesom.
Studijom je obuhvaćen 141
bolesnik koji je preživeo infarkt miokarda, u sinusnom ritmu bez AV
blokova i
blokova grana. Sa dijabetes melitusom bilo je 35 bolesnika, a 106 je
bilo bez
dijabetesa. Prosečna starost ispitanika iznosila je 58,82 godine.
Ispitanicima
je pored kliničkog pregleda i laboratorijskih analiza urađen standardni
EKG,
test fizičkim opterećenjem na pokretnoj traci po Bruce-ovom protokolu,
24-časovni holter monitoring i ehokardiografski pregled. Iz holterskog
zapisa
softverski je vršena analiza HRV. Analizirana su četri parametra
vremenske
analize HRV: SDNN, SDANN, RMS-SD i NN > 50ms.
Bolesnici sa preživelim
infarktom miokarda i dijabetesom imali su značajno manje vrednosti
praćenih
parametara HRV u odnosu na one bez dijabetesa (89,47 ± 30,82
: 103,28 ± 32,18 ms; p < 0,025 za SDNN;
28,50 ± 13,71 : 35,22 ± 12,42 ms;
p < 0,02 za RMS-SD; 77,26 ± 27,58 :
88,74 ± 30,58 ms; p < 0,05 za SDANN i
7,45 ± 8,63 : 11,07 ± 9,08 ms;
p < 0,05 za NN > 50 ms). Takođe,
bolesnici sa dijabetesom imali su značajno manje vrednosti LVEF
(49,19 ± 8,01 : 52,84 ± 11,24 %;
p < 0,05), a značajno veće vrednosti LVESd
(39,39 ± 4,82 : 37,03 ± 6,18 mm;
p < 0,025), kao i veći stepen dijastolne
disfunkcije leve komore u odnosu na one bez dijabetesa
(0,82 ± 0,18 : 0,91 ± 0,21; p < 0,02
za odnos E/A i 183,52 ± 47,29 : 214,32 ± 46,15;
p < 0,005 za Dt). Studija je pokazala da postoji
značajna pozitivna korelacija vrednosti SDNN i SDANN sa LVEF (r =
0,510; p < 0,01
za SDNN i r = 0,569; p < 0,01 za SDANN), a značajna
negativna
korelacija sa LVESd (r = -0,361;
p < 0,05 za SDNN i r = -0,364;
p < 0,05 za SDANN), dok sa LVEDd korelacija nije dostigla
nivo
značajnosti, kod bolesnika sa preživelim infarktom miokarda i
dijabetesom.
Vrednosti parametara RMS-SD i NN > 50 ms nisu značajno
korelisale
sa LVEF i unutrašnjim dimenzijama leve komore kod bolesnika sa
preživelim
infarktom miokarda i dijabetesom.
Studija
je pokazala da bolesnici sa preživelim infarktom mikarda i dijabetesom
imaju
značajno manje vrednosti parametara varijabilnosti frekvencije srčanog
rada i
vrednosti LVEF, značajno veće vrednosti LVESd, kao i značajno veći
stepen
dijastolne disfunkcije leve komore, u odnosu na one bez dijabetesa.
Postoji
značajna pozitivna korelacija parametara SDNN i SDANN sa LVEF, a
značajna
negativna korelacija sa LVESd u bolesnika sa preživelim infarktom
mikarda i
dijabetesom.
Ključne reči: Varijabilnosti frekvencije srčanog rada, funkcija
leve komore, infarkt miokarda, dijabetes melitus
