@article{MTMT:34484706,
	title = {Aortabillentyű-beültetés antifoszfolipid szindrómában},
	url = {https://m2.mtmt.hu/api/publication/34484706},
	author = {Szántó, Tamás and Béres, Szabolcs and Husznai, Róbert and Kiss, Rudolf and Kellermayer, Dalma and Tornóczky, Tamás and Hejjel, László},
	doi = {10.1556/1046.2023.40002},
	journal-iso = {MAGYAR SEBÉSZET},
	journal = {MAGYAR SEBÉSZET},
	volume = {76},
	unique-id = {34484706},
	issn = {0025-0295},
	abstract = {Egy 44 éves férfi betegnél endokarditisz talaján kialakult súlyos aortabillentyű-elégtelenség tett szükségessé szívsebészeti beavatkozást. A kevesebb mint egy év alatt bekövetkezett többszöri trombotikus esemény felvetette antifoszfolipid szindróma lehetőségét. A lupus antikoaguláns pozitivitás és az említett klinikai kép ezt igazolta.Betegünk fiatal életkora és a biológiai műbillentyű korlátozott élettartama ellenére biológiai műbillentyű beültetése mellett döntöttünk. Választásunkat azzal indokoljuk, hogy tanulmányok bizonyítják antifoszfolipid szindrómás betegeknél a mechanikus műbillentyűvel összefüggésbe hozható thromboembolia viszonylag gyakori előfordulását. A műtétet szövődménymentesen elvégeztük, aktivált parciális thromboplastin idővel kontrollált Na-heparin korai adása mellett állítottuk be az orális antikoaguláns terápiát 3,0 INR célértékkel a műtét utáni ötödik napra. A műtét során eltávolított billentyűből korokozó nem tenyészett ki. A kórszövettani vizsgálat abakteriális endokarditiszt véleményezett, nem kizárva a korábbi fertőzést. Biológiai műbillentyű implantáció után három hónapig ajánlott aszpirin vagy K-vitamin antagonista adása, betegünk esetében viszont élethosszig tartó antikoaguláns kezelés szükséges, tekintettel rendszerbetegségére.Halmozódó tromboembóliás események kapcsán gondolni kell antifoszfolipid szindrómára, mely igazolása adott esetben meghatározhatja a választható műbillentyű fajtáját. Az ajánlások legtöbbször csak általánosságban fedik le a ritka társbetegségeket, ezért a kapcsolódó szakirodalom áttekintése is szükséges az optimális, betegre szabott döntéshez.},
	keywords = {ANTIPHOSPHOLIPID SYNDROME; Infective endocarditis; Aortic valve implantation; antifoszfolipid szindróma; aortabillentyű implantáció; endokarditisz},
	year = {2023},
	eissn = {1789-4301},
	pages = {111-115},
	orcid-numbers = {Béres, Szabolcs/0000-0001-9710-0275}
}

@article{MTMT:34180182,
	title = {Determinants of the heart rate variability in type 1 diabetes mellitus},
	url = {https://m2.mtmt.hu/api/publication/34180182},
	author = {Hajdu, Máté and Garmpis, Konstandia and Vértes, Vivien and Varga, Noémi and Molnár, Gergő Attila and Hejjel, László and Wittmann, István and Faludi, Réka},
	doi = {10.3389/fendo.2023.1247054},
	journal-iso = {FRONT ENDOCRINOL},
	journal = {FRONTIERS IN ENDOCRINOLOGY},
	volume = {14},
	unique-id = {34180182},
	issn = {1664-2392},
	abstract = {<sec>BackgroundEvaluation of heart rate variability (HRV) detects the early subclinical alterations of the autonomic nervous system. Thus, impaired HRV is the earliest subclinical marker of cardiac autonomic neuropathy (CAN) in type 1 diabetes mellitus (T1DM).</sec><sec>ObjectivesWe aimed to explore the HRV parameters in asymptomatic T1DM patients and compare them with the results obtained in healthy subjects. Potential associations between HRV parameters and the established risk factors for CAN and cardiovascular diseases were also investigated.</sec><sec>MethodsSeventy T1DM patients (38 ± 12 years, 46 females) and 30 healthy subjects were enrolled into the study. For HRV analysis, beat-to-beat heart rate was recorded for 30 min. The less noisy 5-min segment of the recording was analyzed by Bittium Cardiac Navigator HRV analysis software. Time domain, frequency domain, and nonlinear indices were calculated.</sec><sec>ResultsRegarding ratio of low to high frequency component (LF/HF), no differences were found between the two populations (p = 0.227). All the further, time domain, frequency domain, and nonlinear HRV indices were significantly lower in T1DM patients (each p < 0.001). In multiple linear models, disease duration remained the only independent predictor of LF/HF ratio (p = 0.019). HbA1c was found to be significant independent predictor of all further time domain (SDNN, p < 0.001; rMSSD, p < 0.001), frequency domain (VLF, p < 0.001; LF, p = 0.002; HF, p = 0.006; Total Power, p = 0.002), and nonlinear indices (SD1, p = 0.006; SD2, p = 0.007), alone, or in combination with other factors, such as age or body mass index.</sec><sec>ConclusionAsymptomatic T1DM patients have significantly reduced overall HRV as compared with healthy subjects, indicating subclinical CAN. Quality of the glycemic control is important determinant of HRV among T1DM patients. This relationship is independent of other risk factors for CAN or cardiovascular diseases.</sec>},
	year = {2023},
	eissn = {1664-2392},
	orcid-numbers = {Molnár, Gergő Attila/0000-0001-6052-5907}
}

@article{MTMT:34173278,
	title = {A kardiális reszinkronizációs kezelésben részesülő betegek interdiszciplináris gondozása},
	url = {https://m2.mtmt.hu/api/publication/34173278},
	author = {Kosztin, Annamária and Polgár, Balázs and Kónyi, Attila and Hejjel, László and Gellér, László Alajos and Vámos, Máté},
	doi = {10.26430/CHUNGARICA.2023.53.4.365},
	journal-iso = {CARDIOL HUNG},
	journal = {CARDIOLOGIA HUNGARICA},
	volume = {53},
	unique-id = {34173278},
	issn = {0133-5596},
	abstract = {Bár a kardiális reszinkronizációs kezelés (CRT) klinikai végpontokra kifejtett kedvező hatása jól ismert, sajnos nem minden beteg reagál ugyanolyan mértékben a kezelésre, a nonreszponderitás továbbra is fontos probléma. A reszponderitás arányának optimalizálása a műtét előtti betegkiválasztásnál kezdődik, jelentősége van a beültetett eszközök/ elektródák típusának és a beültetés módjának, valamint a szoros követésnek is. A CRT-re adott válasz értékelése közös feladata a beteget gondozó kardiológusnak, szívelégtelenség specialistának, az echokardiográfiás kontrollt végzőnek, a készüléket ellenőrző elektrofiziológusnak és a családorvosnak. Jelen összefoglalóban ezeket a speciális beteggondozási feladatokat, illetve optimalizációs lehetőségeket tekintjük át.},
	year = {2023},
	eissn = {1588-0230},
	pages = {365-374},
	orcid-numbers = {Kosztin, Annamária/0000-0001-6647-2623; Gellér, László Alajos/0000-0001-6802-6360}
}

@article{MTMT:33802298,
	title = {The Effect of Device-Controlled Breathing on the Pulse Arrival Time and the Heart Rate Asymmetry Parameters in Healthy Volunteers},
	url = {https://m2.mtmt.hu/api/publication/33802298},
	author = {Ajtay, Bella Eszter and Béres, Szabolcs and Hejjel, László},
	doi = {10.3390/app13095642},
	journal-iso = {APPL SCI-BASEL},
	journal = {APPLIED SCIENCES-BASEL},
	volume = {13},
	unique-id = {33802298},
	abstract = {Background: The development of wearables has facilitated the monitoring of biomedical parameters in everyday life. One of the most common sensors of these gadgets is the photoplethysmograph (PPG); hence, the proper processing and interpretation of the PPG signal are essential. Besides pulse rate detection, these devices—together with an ECG—compute the pulse arrival time (PAT), from which the actual beat-to-beat blood pressure can be estimated. The heart rate shows asymmetrical accelerations and decelerations, quantified by the parameters of heart rate asymmetry (HRA). In the present study, we investigated the influences of different breathing-patterns on the PATs and HRA parameters. Methods: The authors evaluated 5 min simultaneous respiratory-, ECG- and PPG-signal recordings of 35 healthy, young volunteers specifically expressing the following breathing patterns: metronome-controlled inspiration, and both inspiration and expiration controlled at 1:1 and 1:2 ratios, respectively. The records were analyzed by HRVScan_Merge v3.2 software. The PAT values were calculated at eight different reference points. The HRA parameters and the PAT values at different breathing patterns were compared using the Friedman test and post hoc Wilcoxon paired-sample test. Results: Porta- and Guzik-indices significantly increased at 1:1 breathing compared to 1:2 and single-paced breathing. PATs increased significantly in dual-paced series compared to single-paced series at each reference point. Conclusion: Based on our results, the increased PATs at dual-paced versus single-paced breathing may indicate the involvement of cognitive functions. The symmetrical respiration ratio increases the heart rate symmetry; however, this effect is not detectable in the periphery through the PATs.},
	year = {2023},
	eissn = {2076-3417},
	orcid-numbers = {Béres, Szabolcs/0000-0001-9710-0275}
}

@article{MTMT:33050034,
	title = {The oscillating pulse arrival time as a physiological explanation regarding the difference between ECG- and Photoplethysmogram-derived heart rate variability parameters},
	url = {https://m2.mtmt.hu/api/publication/33050034},
	author = {Ajtay, Bella Eszter and Béres, Szabolcs and Hejjel, László},
	doi = {10.1016/j.bspc.2022.104033},
	journal-iso = {BIOMED SIGNAL PROCES},
	journal = {BIOMEDICAL SIGNAL PROCESSING AND CONTROL},
	volume = {79},
	unique-id = {33050034},
	issn = {1746-8094},
	abstract = {Background and Objective: ECG-based heart rate variability (HRV), and more recently, optical pulse rate variability (PRV) analysis used in wearables are non-invasive tools of neurocardiac investigation. Pulse arrival time (PAT) is derived from their simultaneous recording. We examined the beat-to-beat PAT in greater detail, while analyzed the PRV to HRV relationship. Methods: We acquired 300sec ECG, photoplethysmogram (PPG), and respiratory-signals from 35 young, healthy volunteers while in a supine position including different breathing patterns. PAT at eight reference points on the PPG-side was assessed by the mean, relative precision (RP%) and spectral analysis. PRV and HRV parameters were compared by relative accuracy error (RAE) and the Bland-Altman-Ratio (BAR). Results: PAT showed the minimum RP% at the 1/2-amplitude point whereas RP% reached the maximum at the base point; its observed fine oscillation was associated to breathing as confirmed through spectral analysis. The instantaneous slope of PPG rise is inversely proportional to the corresponding PAT. RAE and BAR showed excellent agreement in 15 of 16 analysis at time-domain, mostly excellent or moderate on frequency-domain and nonlinear analysis. The inherent difference between HRV and PRV is formally due to the difference among two consecutive PATs. Conclusion and Significance: The present study supported the interchangeability of HRV- and PRV-analysis. Our formalistic explanation linking successive PAT-pairs and the inborn difference between HRV and PRV may bear further implications in selecting the appropriate fiducial points, approximating PRV to HRV measures, and in creating innovative neurocardiac parameters or complex PPG models/simulators. © 2022},
	keywords = {HEART; Spectrum Analysis; heart rate variability; Nonlinear analysis; Time domain analysis; Physiological models; Frequency domain analysis; Photoplethysmography; Relative accuracy; Simultaneous recording; ECG signals; Variability analysis; Pulse arrival time; electrocardiograms; photoplethysmogram; respiratory signals; pulse rate variability; accuracy errors},
	year = {2023},
	eissn = {1746-8108},
	orcid-numbers = {Béres, Szabolcs/0000-0001-9710-0275}
}

@article{MTMT:34104415,
	title = {A glikémiás kontroll minősége szignifikánsan befolyásolja a szívfrekvencia variabilitást 1-es típusú diabéteszben = Quality of glycaemic control has significant impact on heart rate variability in type 1 diabetes mellitus},
	url = {https://m2.mtmt.hu/api/publication/34104415},
	author = {Hajdu, Máté and Garmpis, Konstandia and Vértes, Vivien and Vorobcsuk-Varga, Noémi and Hejjel, László and Molnár, Gergő Attila and Wittmann, István and Faludi, Réka},
	journal-iso = {CARDIOL HUNG},
	journal = {CARDIOLOGIA HUNGARICA},
	volume = {52},
	unique-id = {34104415},
	issn = {0133-5596},
	year = {2022},
	eissn = {1588-0230},
	pages = {335-335},
	orcid-numbers = {Molnár, Gergő Attila/0000-0001-6052-5907}
}

@inproceedings{MTMT:32925495,
	title = {Data Quality Enhancement for Machine Learning on Wearable ECGs},
	url = {https://m2.mtmt.hu/api/publication/32925495},
	author = {Molnár, B. and Micsinyei, L. and Perlaki, Gábor and Orsi, Gergely and Hejjel, László and Dóczi, Tamás Péter and Janszky, József Vladimír and Laky, N. and Tényi, Á.},
	doi = {10.1007/978-3-031-07704-3_22},
	volume = {13346 LNBI},
	unique-id = {32925495},
	year = {2022},
	pages = {269-279},
	orcid-numbers = {Janszky, József Vladimír/0000-0001-6100-832X}
}

@article{MTMT:32800048,
	title = {Physical Vascular Therapy (BEMER) Affects Heart Rate Asymmetry in Patients With Coronary Heart Disease.},
	url = {https://m2.mtmt.hu/api/publication/32800048},
	author = {Kreska, Zita and Mátrai, Péter and Németh, Balázs and Ajtay, Bella Eszter and Kiss, István and Hejjel, László and Ajtay, Zénó},
	doi = {10.21873/invivo.12845},
	journal-iso = {IN VIVO},
	journal = {IN VIVO},
	volume = {36},
	unique-id = {32800048},
	issn = {0258-851X},
	abstract = {The aim of this study was to assess the acute effects of physical vascular therapy (PVT) on the autonomous nervous system by heart rate variability (HRV) and heart rate asymmetry (HRA) analysis. The low-frequency, pulsed electromagnetic field (<35 μTesla) with a patented BEMER pattern can improve vasomotion and microcirculation. A non-invasive confirmation of the instant effects of PVT may provide an opportunity to give an immediate feedback to the patient and therapist.Altogether 48 patients on inward rehabilitation with coronary heart disease (CHD) were involved, their treatment included PVT with B.Box Professional and B.Body Pro applicator (BEMER International AG, Triesen, Lichtenstein). After 15 min of postural adaptation, 6-min electrocardiograms (ECG) were taken immediately before, in the first and in the last 6 min of the 20-min PVT, and one hour after the treatment. Of the 48 patients, the last twenty patients received sham PVT with the same protocol. Off-line analysis was blinded. We used linear mixed statistical model to compare HRV and HRA parameters.The time domain parameters did not show any statistically significant differences between the changes in the real PVT and sham groups but, in the first stage of the treatment, Porta and Guzik indices significantly rose everywhere except in the sham group.PVT significantly increases the Guzik and Porta indices in chronic ischemic heart disease patients reflecting a delicate autonomic response. HRA as a measure of autonomic regulation seems to be more sensitive than time domain parameters.},
	keywords = {heart rate variability; rehabilitation; Pulsed electromagnetic field; heart rate asymmetry; physical vascular therapy (BEMER)},
	year = {2022},
	eissn = {1791-7549},
	pages = {1408-1415},
	orcid-numbers = {Németh, Balázs/0000-0002-4914-9872}
}

@article{MTMT:31969946,
	title = {The minimal sampling frequency of the photoplethysmogram for accurate pulse rate variability parameters in healthy volunteers},
	url = {https://m2.mtmt.hu/api/publication/31969946},
	author = {Béres, Szabolcs and Hejjel, László},
	doi = {10.1016/j.bspc.2021.102589},
	journal-iso = {BIOMED SIGNAL PROCES},
	journal = {BIOMEDICAL SIGNAL PROCESSING AND CONTROL},
	volume = {68},
	unique-id = {31969946},
	issn = {1746-8094},
	year = {2021},
	eissn = {1746-8108},
	orcid-numbers = {Béres, Szabolcs/0000-0001-9710-0275}
}

@article{MTMT:31857900,
	title = {Comment on 'Pulse rate variability in cardiovascular health : a review on its applications and relationship with heart rate variability'},
	url = {https://m2.mtmt.hu/api/publication/31857900},
	author = {Hejjel, László and Béres, Szabolcs},
	doi = {10.1088/1361-6579/abd332},
	journal-iso = {PHYSIOL MEAS},
	journal = {PHYSIOLOGICAL MEASUREMENT},
	volume = {42},
	unique-id = {31857900},
	issn = {0967-3334},
	abstract = {Precise beat-to-beat fiducial point detection in the photoplethysmogram signal is essential for reliable pulse rate variability (PRV) analysis, which is considered an integral part of health monitoring devices in the evolving era of mobile health. Several studies have aimed to compare PRV to the well-investigated, gold standard heart rate variability (HRV) analysis, to see if they are interchangeable. The agreement between PRV and HRV is not unequivocal, as we learn from the commented metaanalysis. Technical factors like low sampling rate of photoplethysmography (PPG) or imprecise fiducial point detection are more important in this difference than physiological factors corresponding to pulse arrival time. Standardization of the PPG acquisition and reference point detection is necessary for comparable studies and correct measurement.},
	year = {2021},
	eissn = {1361-6579},
	orcid-numbers = {Béres, Szabolcs/0000-0001-9710-0275}
}