www.ksmf.org/arhimed   arhimed@ksmf.org   [5/10/2025 11:26:09 AM] http://www.ksmf.org/arhimed/poglej.asp?id=16 Casovne spremembe variabilnosti srcne frekvence pri bolnikih po prebolelem srcnem infarktu Avtor: Tadeja Pacnik, Simona Rupnik Mentor: prof. dr. Peter Rakovec, dr. med. IZHODIŠCE: Ob akutnem srcnem oziroma miokardnem infarktu (AMI) pride do sprememb v aktivnosti avtonomnega živcevja srca. Te spremembe lahko ocenjujemo z merjenjem variabilnosti srcne frekvence (VSF), ki se ob AMI zmanjša.V literaturi zasledimo razlicna in delno nasprotujoca si mnenja o tem, v kolikšni meri in v kakšnem casu po AMI se zmanjšana VSF poveca. Vecina raziskav pa vendar kaže, da se VSF povecuje že v prvih tednih po AMI. NAMEN: Preveriti smo hoteli delovno hipotezo, da se VSF statisticno pomembno poveca že v prvih dveh mesecih in pol po nastopu AMI. Poleg tega smo proucevali vplive velikosti in lokalizacije AMI, starosti, sladkome bolezni in arterijske hipertenzije na VSF. METODE: Raziskavo smo zasnovali prospektivno. Pri 22 bolnikih (4 ženske, 18 moških) s povprecno starostjo 54,7 1eta (54,7 f10,2) smo prvic merili VSF med 4. in 12. dnem po nastopu AMI in drugic 39 do 76 dni po nastopu AMI. Iz 15-minutnih elektrokardiografskih (EKG) posnetkov smo dolocali spektralne in nekatere casovne kazalce VSF. Velikost AMI smo dolocali po encimskih merilih. Razliko med dvema skupinama podatkov in korelacijo smo imeli kot statisticno pomembni pri p<0,05. REZULTATI: Med prvo in drugo meritvijo statisticno pomembnih razlik v vrednostih kazalcev VSF nismo ugotovili (p>0,3; za vse kazalce VSF). Tudi kazalci VSF pri bolnikih z razlicno obsežnim AMI se med prvo in drugo meritvijo niso razlikovali. S starostjo je statisticno pomembno negativno korelirala nizkofrekvencna komponenta VSF (r-0,475; p=0,027). Bolniki s sladkomo boleznijo so imeli v primerjavi z bolniki brez te bolezni statisticno pomembne razlike v naslednjih kazalcih VSF: spektralna amplituda celotnega frekvencnega podrocja (p=0,048), spektralna amplituda nizkofrekvencne komponente (p=0,036), spektralna amplituda visokofrekvencne komponente (p=0,006), dolžina intervala RR (p=0,031) in standardna deviacija intervalov RR (p=0,018). Bolniki z arterijsko hipertenzijo so se od bolnikov brez te bolezni statisticno pomembno razlikovali v spektralni amplitudi nizkofrekvencne komponente VSF (p=0,016). Bolniki z AMI sprednje stene so imeli v primerjavi z bolniki z AMI spodnje stene statisticno pomembno razliko v dveh kazalcih VSF: spektralna amplituda celotnega frekvencnega podrocja (p=0,031) in standardna deviacija intervalov RR (p=0,042). ZAKLJUCKI: Raziskava ni potrdila delovne hipoteze, temvec je pokazala, da se VSF v prvih dveh mesecih in pol po AMI ni povecala. Tako nismo mogli ocenjevati vpliva velikosti AMI na casovne spremembe VSF. S starostjo, sladkomo boleznijo in z arterijsko hipertenzijo se VSF zmanjsuje. Odvisna je tudi od lokalizacije AMI - pri bolnikih z AMI sprednje stene je bila VSF nižja kot pri bolnikih z AMI spodnje stene. «» [Abstract / English version] Time course of heart rate variability changes in patiens after acute myocardial infarction Author: Tadeja Pacnik, Simona Rupnik Mentor: prof. dr. Peter Rakovec, dr. med. BACKGROUND: Acute myocardial infarction (AMI) causes several abnormalities of the autonomic control to the heart. These abnormalities can be observed by measuring heart rate variability (HRV), which gets lower after AMI. In literature there are a lot of different and contradictive opinions about the degree and time in which the lowered HRV increases. However the majority of research work shows that HRV increases already in the first few weeks after AMI. PURPOSE: The main purpose of the research is to confirm the regularity of the hypothesis that HRV rises already in the first two months and a half after AMI. Besides that the influence of AMI size and localisation, and also age, diabetes mellitus, arterial hypertension on HRV have been explored. METHODS: The research was done from the perspective point of view. Among 22 patients (4 women and 1 8 men), the average age was 54.7, (54.7 f10.2 years) HRV being first measured between day 4 and 12 after AMI and for the second time 39 to 76 days after AMI. From 15-minutes long electrocardiographic (ECG) recordings spectral and some time indicators of HRV were calculated. The size of AMI were defined by cardiac enzyme measurements. The difference between two groups of data and correlation were considered statistically important at p< 0.05. RESULTS: No statistically important score differences of HRV indicators were found out between the first and the second measuring (p>3; for all HRV indicators); not even in patients with different AMI size. According to the age there was a significant negative correlation of low frequency amplitude (r-0.475; p=0.027). In comparison to healthy people diabetes mellitus patients showed significant changes in the following HRV indicators: total spectral amplitude (p=0.048), low frequency amplitude (p=0.036), high frequency amplitude (p=0.006), RR interval length (p=0.031) and standard RR interval deviation (p=0.018). Arterial hypertension patients compared to those lacking the disease showed statistically important differences in low frequency spectral amplitude (p=0.016). Patients with anterior AMI differed from those with the inferior AMI in two significant HRV indicators: total spectral amplitude (p=0.03 1 ) and standard RR interval deviation (p=0.042). CONCLUSIONS: The study did not confirm the hypothesis but demonstrates that HRV has not changed in the first two months and a half after AMI. Because of that it was not possible to explore the effect of AMI size on time-dependent changes of HRV. HRV declines with the age, diabetes mellitus and arterial hypertension. It also depends on AMI localisation - with anterior AMI patients HRV was lower than with inferior AMI patients.