Cardiac resynchronization therapy with intraoperative epicardial mapping via minithoracotomy: 10 years' experience.

BACKGROUND: Cardiac resynchronization therapy (CRT) is considered an efficient method to improve the left ventricular (LV) dysfunction with left bundle branch block. However, coronary venous anatomy is not appropriate in about 10% of the cases; thus other alternatives, such as epicardial lead implantation via minithoracotomy are needed. METHODS: During the period 2007-2017, a total of 57 patients were operated at our institute via left anterior minithoracotomy after an unsuccessful transvenous CRT. The best position of the LV epicardial electrode was determined by intraoperative epicardial mapping, that is locating the latest activation spot relative to the right ventricular (RV) electrode. The authors analyzed the survival by Kaplan-Meier estimator with Tarone-Ware equality test and multiple Cox regression analysis, the changes of the LV ejection fraction (LVEF) and dimensions, the development of the impedance and threshold of the LV epicardial electrode, the possible associations between the survival and intraoperative sensed RV-LV activation delay. RESULTS: The intraoperative RV-LV activation delay was 92.250 ± 26.538 milliseconds. There were no intraoperative complications except ventricular fibrillation in three patients. Within 30 days there were neither wound healing complications nor pocket hematoma. There was no significant difference in survival with regard to gender or etiology, but significantly better survival was found in the cohort with intraoperative sensed RV-LV activation delay >86 milliseconds. The LVEF and dimensions improved following the operation and continued to be improved in the survivors. CONCLUSION: CRT via minithoracotomy with epicardial mapping is a safe, efficient, simple, and reproducible second-line alternative to the transvenous method.

[Perioperative use of levosimendan in cardiac surgery. Hungarian recommendation]. / A levoszimendán perioperatív alkalmazása a szívsebészetben. Magyar ajánlás.

Low output syndrome significantly increases morbidity and mortality of cardiac surgery and lengthens the durations of intensive care unit and hospital stays. Its treatment by catecholamines can lead to undesirable systemic and cardiac complications. Levosimendan is a calcium sensitiser and adenosine triphosphate (ATP)-sensitive potassium channel (IK,ATP) opener agent. Due to these effects, it improves myocardium performance, does not influence adversely the balance between O2 supply and demand, and possesses cardioprotective and organ protective properties as well. Based on the scientific literature and experts' opinions, a European recommendation was published on the perioperative use of levosimendan in cardiac surgery in 2015. Along this line, and also taking into consideration cardiac surgeon, anaesthesiologist and cardiologist representatives of the seven Hungarian heart centres and the children heart centre, the Hungarian recommendation has been formulated that is based on two pillars: literature evidence and Hungarian expert opinions. The reviewed fields are: coronary and valvular surgery, assist device implantation, heart transplantation both in adult and pediatric cardiologic practice. Orv Hetil. 2018; 159(22): 870-877.

Effects of spinal cord stimulation on heart rate variability in patients with chronic pain.

BACKGROUND: Spinal cord stimulation has become an established clinical option for treatment of refractory chronic pain and angina pectoris, but its precise mechanism of action is unclear. We investigated the effect of spinal cord stimulation (SCS) on heart rate variability (HRV) and evaluating its influence on the sympathetic/parasympathetic balance in chronic pain. MATERIALS AND PURPOSE: Seven patients (three men, four women) with SCS due to chronic pain were included. The SCS was programmed in three different ways: (i) to stimulate at an amplitude known to generate paresthesias (ON-state), (ii) at a subliminal level (SUB state), or (iii) switched off (OFF-state). HRV analysis was based on 5-min segments of the consecutive normal RR intervals and was performed with custom software (Kubios HRV Analysis). RESULTS: The mean heart rate was higher in ON state compared to SUB state (p = 0.018) and the high-frequency component of the HRV was lower in ON compared to OFF period (p = 0.043). Other HRV parameters values did not significantly differ during the three tested periods. CONCLUSION: Spinal cord stimulation in chronic pain seems to be accompanied by reduced parasympathetic tone, unlike SCS in angina pectoris where previous studies found a reduced cardiac sympathetic tone. Our study might lead to understand the mechanism of action of SCS We investigated a relatively small number of patients, which is the main limitation of our study. Thus, further studies with larger number of patients are required for validation of our results.

Aortabillentyu-beültetés antifoszfolipid szindrómában.

Esetismertetés: Egy 44 éves férfi betegnél endokarditisz talaján kialakult súlyos aortabillentyu-elégtelenség tett szükségessé szívsebészeti beavatkozást. A kevesebb mint egy év alatt bekövetkezett többszöri trombotikus esemény felvetette antifoszfolipid szindróma lehetoségét. A lupus antikoaguláns pozitivitás és az említett klinikai kép ezt igazolta. Megbeszélés: Betegünk fiatal életkora és a biológiai mubillentyu korlátozott élettartama ellenére biológiai mubillentyu beültetése mellett döntöttünk. Választásunkat azzal indokoljuk, hogy tanulmányok bizonyítják antifoszfolipid szindrómás betegeknél a mechanikus mubillentyuvel összefüggésbe hozható thromboembolia viszonylag gyakori elofordulását. A mutétet szövodménymentesen elvégeztük, aktivált parciális thromboplastin idovel kontrollált Na-heparin korai adása mellett állítottuk be az orális antikoaguláns terápiát 3,0 INR célértékkel a mutét utáni ötödik napra. A mutét során eltávolított billentyubol korokozó nem tenyészett ki. A kórszövettani vizsgálat abakteriális endokarditiszt véleményezett, nem kizárva a korábbi fertozést. Biológiai mubillentyu implantáció után három hónapig ajánlott aszpirin vagy K-vitamin antagonista adása, betegünk esetében viszont élethosszig tartó antikoaguláns kezelés szükséges, tekintettel rendszerbetegségére. Következtetés: Halmozódó tromboembóliás események kapcsán gondolni kell antifoszfolipid szindrómára, mely igazolása adott esetben meghatározhatja a választható mubillentyu fajtáját. Az ajánlások legtöbbször csak általánosságban fedik le a ritka társbetegségeket, ezért a kapcsolódó szakirodalom áttekintése is szükséges az optimális, betegre szabott döntéshez.

Determinants of the heart rate variability in type 1 diabetes mellitus.

Background: Evaluation 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). Objectives: We 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. Methods: Seventy 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. Results: Regarding 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. Conclusion: Asymptomatic 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.

Physical Vascular Therapy (BEMER) Affects Heart Rate Asymmetry in Patients With Coronary Heart Disease.

BACKGROUND/AIM: 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. PATIENTS AND METHODS: 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. RESULTS: 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. CONCLUSION: 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.

Comment on 'Pulse rate variability in cardiovascular health: a review on its applications and relationship with heart rate variability'.

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.

Pharmacotechnological pitfalls of priming--possible source of microembolization during open heart surgery.

OBJECTIVES: Besides low mortality and morbidity rates in cardiac surgery, the associated cognitive dysfunction is the focus of interest. One possible reason is microembolisation. METHODS AND RESULTS: The authors analysed the crystallogenesis in the calcium-containing prime, inspired by their observation that the fluid sometimes becomes turbid during the priming process. Lactated Ringer-based prime solutions were tested, adding mannitol, NaHCO(3), and heparin. The oxygenator was ventilated with compressed medical air. Samples were taken for dynamic light scattering particulate level analysis. The priming was furthermore modelled in the laboratory by mixing the components and then ventilating the mixture through with compressed air. Turbid solutions from the operating room contained 100-6500 nm crystals, while clear solutions contained 20-473 nm particles. In the model, continuous pH measurement showed pH 6.4-7.4 after blending the solutions, which then elevated the pH to 7.5-8.0 after ventilation with concomitant turbidity. The pH of the prime can be stabilized by the addition of ascorbic acid (1-2 mg/ml) and, also, the turbidity may be prevented. CONCLUSION: Ventilating the lactated Ringer-based calcium-containing primes after blending is not advisible because of alkalization and crystallogenesis. Ascorbic acid stabilizes the pH and prevents crystallogenesis in the prime. Pre-bypass filtration is recommended.

Simple and choice reaction times are prolonged following extracorporeal circulation: a potential method for the assessment of acute neurocognitive deficit.

BACKGROUND: Cognitive deficit related to open heart surgery came into the focus of interest according to professional and social expectations. The negative effects on quality of life and the large number of involved patients emphasize the need its investigation. MATERIAL/METHODS: The bedside measurement of simple and choice reaction times (sRT and cRT) has the objectivity of cortical evoked potential analysis without the need for EEG instrumentation and laboratory. This is a functional assessment similar to neuropsychological tests, but requires a significantly shorter time and is less demanding for the patient. RESULTS: Fifty patients who had undergone open heart surgery were investigated. Statistically significant positive correlation of sRT and cRT prolongation and perfusion time was found. At the same time there were no statistically significant changes in mean sRT and cRT values before (sRT: 208+/-54 s, cRT: 369+/-59 s) and after (sRT: 229+/-67 s, cRT: 392+/-105 s) the surgery, probably due to the inhomogeneous patient population. The weak correlation (coefficients: 0.1418-0.8484) for sRT and cRT changes as a function of perfusion time confirms the presence of other factors of postoperative brain damage. CONCLUSIONS: The investigated bedside test is clinically feasible, simple, and can be completed within 30 minutes. Further studies are encouraged to compare this method with other tests in a larger, stratified cardiac surgery population.

[Pumpless extracorporeal lung assist]. / A minimalizált extracorporális tüdôtámogatás.

The recently introduced pumpless extracorporeal lung assist (PECLA) is a remarkable alternative to the conventional extracorporeal membrane oxygenation in case of severe lung failure. By establishing a shunt between femoral artery and vein using the arterio-venous pressure gradient as a driving force through a low-resistance membrane oxygenator, PECLA provides highly effective gas-exchange by preserved cardiac function. Due to its closed system, reduced priming volume and low heparin demand, the unfavourable effects of extracorporeal membrane oxygenation can be effectively diminished. Hence the small technical, financial and personal input, the PECLA can be ideally used in district hospitals and during transport as well. Our short summary demonstrates the advantages and safety of the system proven over 123 cases.

[Effect of epileptic seizures on the heart rate]. / Az epilepsziás rohamok hatása a szívfrekvenciára.

BACKGROUND: Sudden death appears in 8-17% of epilepsy patients non-responding to antiepileptic therapy. Some studies suggest that the most common cause of death is seizure-related cardiac arrhythmia. AIM OF STUDY: To analyze the alteration of the heart rate six hours before and after the seizures. METHODS: Eighteen patients suffering from focal epilepsy were examined before epilepsy surgery. Video-EEG-ECG was carried out for 2-10 days, and 32 seizures were registered. Analysis of the heart rate was based on the 5-minute-long epochs of the ECGs taken at the 5-10-15-30th minutes and at the 1-3-6th hours before and after seizures. RESULTS: The heart rate increases (from an average of 69 beats/min to 92 beats/min, p<0.001) immediately after seizures, though significantly higher heart rate was observed 3 hours after seizures. There were no patients with severe peri-ictal bradycardia. In one of our patients, ectopic cardiac rhythm occurred after a generalized tonic-clonic seizure. CONCLUSIONS: We can conclude that the sympathetic activity increases while the parasympathetic activity decreases after seizures. The observed alterations lasted for a long time and predict fatal arrhythmias. These suggest that sudden death in epilepsy can be induced by cardiac arrhythmias connected with epileptic seizures.

[Dislodged Amplatzer occluder in the aorta]. / Elszabadult Amplatzer-occluder az aortában.

Percutaneous device closure of atrial septal defect (ASD) has merged as an alternative to traditional surgical closure. The authors are presenting the case of a 55-year-old female patient with chest complaints following Amplatzer occluder implantation for closure of secundum type ASD. She had been presented ambulatory at her cardiologist's office 3 days after the discharge from the hospital. Echocardiography revealed persisting ASD and displacement of the device. She had been referred to the Heart Institute of Pécs, where chest X-ray and CT examination were done. The dislocated occluder device was found wedged in the bifurcation of aorta and brachiocephalic trunk. Open heart surgery was indicated and the device was removed, after that the ASD was directly closed. The patient had been discharged in good health at the 5th postoperative day.

Cellular Phone Irradiation of the Head Affects Heart Rate Variability Depending on Inspiration/Expiration Ratio.

BACKGROUND: Mobile phones may have harmful health effects and clinical examinations report ambiguous results of exposure concerning neurophysiological and cardiovascular actions. MATERIALS AND METHODS: This study investigated heart rate asymmetry (HRA) and heart rate variability (HRV) parameters with 1:2 and 1:1 metronome-paced inspiration/expiration ratios during short-term 1,800MHz GSM cellular phone exposure in 20 healthy volunteers. RESULTS: Significant HRA changes by Porta and Guzik indices were not found on exposure compared to sham exposure. Time-domain HRV parameters on exposure showed significant differences at 1:1 paced, but not at 1:2 paced breathing compared to sham exposure. A mild post-exposure effect was observed regarding root mean square of successive RR-differences. CONCLUSION: The findings reflect persisting acute effects of GSM handset emission on the autonomic nervous system. Exploring its influences on health status and survival needs further studies. Symmetrical breathing can be used as a sensitizing factor in other HRV/HRA analysis studies.

Transcutaneous Carbon Dioxide Treatment Affects Heart Rate Variability - A Pilot Study.

BACKGROUND: The aim of this study was to investigate the effects of carbon-dioxide treatment on heart rate variability (HRV) parameters: mean RR interval (RRI), standard deviation of RR intervals (SDNN), root mean square of successive RR differences (RMSSD); and Porta and Guzik indices, as measures of heart rate asymmetry. MATERIALS AND METHODS: Twenty patients were enrolled (mean±SD, age=59±7.8 years). Measurements were performed before CO2 treatment, at the beginning of treatment, at 15 min of treatment, immediately after and 1 h after the treatment. RESULTS: Significant increase in SDNN was found 1 h after the treatment when compared to that before it (p=0.011). There were no significant changes in other parameters. CONCLUSION: CO2 treatment can influence the autonomic nervous system identified by SDNN changes. However, larger studies are required to confirm these results.

[The principles of minimal extracorporeal circulation and its uses]. / A minimalizált extracorporalis keringés és alkalmazási területei.

The recently introduced minimal extracorporeal circulation system is a remarkable alternative to the conventional heart-lung machine in several cardiosurgical indications. It consists of a centrifugal pump, an oxygenator, a tip-to-tip heparin coated line set and a modified cell saver application. Due to its closed blood-air interaction-free construction and reduced priming volume, the unfavourable effects of perfusion as haemodilution, inflammatory response, locoregional malperfusion, transfusion needs, can be effectively reduced. Our short summary demonstrates the advantages and safety of the system proven over 2000 cases. The potential applications are aortocoronary bypass operations with or without arrest, left heart bypass at thoracal aneurysms, "bridge to recovery" in heart failure or subsequent to reanimation, extracorporeal membrane oxygenation and many more.

Comment on 'Photoplethysmography sampling frequency: pilot assessment of how low can we go to analyze pulse rate variability with reliability?'

Accurate pulse rate detection is essential for reliable pulse rate variability analysis. On the other hand, minimizing the sampling frequency is essential to reduce the amount of data and computational needs, and consequently the power consumption of mobile/wearable devices, extending their operating hours. Determining the variability of physiological parameters needs a new paradigm since there is a limited possibility of calculating an average eliminating random error of measurement. Finding the optimal sampling rate depends on the actual investigation, the expected variability and variability-changes of the study-population in order to get valid HRV parameters.

The issue of plasma asymmetric dimethylarginine reference range - A systematic review and meta-analysis.

BACKGROUND: Asymmetric dimethylarginine (ADMA) is an endogenous inhibitor of nitric oxide synthase, marker and mediator of endothelial dysfunction. Several studies have demonstrated its value in cardiovascular risk stratification and all-cause mortality prediction. The aim was to determine the reference range of plasma ADMA in healthy adults. METHODS AND RESULTS: Taking into account the most widely used ADMA measurement methods, only studies using either high performance liquid chromatography (HPLC) -with fluorescence or mass spectrometric detection-, or enzyme-linked immunosorbent assay (ELISA) to quantify plasma ADMA concentrations were enrolled. 66 studies were included in the quantitative analysis (24 using ELISA and 42 using HPLC) reporting a total number of 5528 non-diabetic, non-hypertensive, non-obese adults without any medication (3178 men and 2350 women, 41.6 ± 16.9 years old). The reference range of ADMA (in µmol/l with 95% confidence interval in parenthesis) was 0.34 (0.29-0.38)- 1.10 (0.85-1.35) with a mean of 0.71 (0.57-0.85) (n = 4093) measured by HPLC and 0.25 (0.18-0.31)- 0.92 (0.76-1.09) with a mean of 0.57 (0.48-0.66) (n = 1435) by ELISA. CONCLUSIONS: Numerous publications suggested that asymmetric dimethylarginine is not only an outstanding tool of disease outcome prediction but also a new potential therapeutic target substance; the reference range provided by this meta-analysis can become of great importance and aid to further investigations. However, developing a standard measurement method would be beneficial to facilitate the clinical usage of ADMA.

The application of surface plethysmography for heart rate variability analysis after GSM radiofrequency exposure.

The aim of the present study was to test whether the electromagnetic field emitted by standard GSM mobile phones results in changes in heart rate (HR) and heart rate variability (HRV) of 35 healthy young male and female subjects. Two parallel signals, electrocardiogram and infrared surface plethysmogram were recorded and compared to test their validity for the analysis. Plethysmographic recording is proved to be a fast and reliable method for HRV measurements. In the radiofrequency (RF) exposure study, there was no significant difference in the values of HR and HRV between the RF and the sham groups. Our preliminary study demonstrates that, in our experimental conditions, RF fields emitted by cellular phones do not cause observable effects on the regulation of heart rate of healthy, young adults.

[Ruptured and reruptured sinus of Valsalva aneurysm]. / Sinus valsalva aneurizma ruptúra és reruptúra.

Aneurysm of the sinus of Valsalva (SVA) is a rare condition of the aorta. It progrediates slowly and can be hidden for a long time, but during its development it may cause various symptoms due to compression. Rupture of the aneurysm can result in acute heart failure necessitating an urgent operative treatment. We operated on a patient with symptoms of acute heart failure, grade III-IV tricuspid insufficiency, loud systolo-diastolic murmur and an extremely high calculated right ventricular pressure. The echocardiography discovered the rupture of the non-coronary sinus of Valsalva shunting to the right ventricle. During the operation we removed the aneurysm sac, and closed the hole directly with running sutures. The involved non-coronary cusp ruptured in the early postoperative course, so an acute reoperation was performed, during which we decided to replace the valve. We must take into account the rupture of SVA in the presence of above symptoms and consider valve replacement instead of repair regarding to the delicate valve apparatus.

The corner frequencies of the ECG amplifier for heart rate variability analysis.

Heart rate variability (HRV) analysis is considered a popular method both in clinical and research fields. However, several ignored technical artifacts may falsify its measurements. The current study investigates the effects of corner frequencies of the ECG amplifier on the precision of RR-interval detection. Clear or noise-corrupted ECG records with predefined parameters consisting of 21 cycles were generated, played back through analog filters and data-logged on a Pentium-based computer with a DaqBoard2000 data acquisition card. 0.1-10 Hz second-order high pass and 20-100 Hz fourth-order low pass Bessel and Butterworth filters were used. The RR-intervals were measured between seven reference points of the ventricular complexes before and after filtering. High and low pass at every frequency cutoff and with both filter types results in correct RR-intervals within 1 ms error. However, a lower cutoff below 1 Hz is needed to maintain ECG morphology. AC interference or Gaussian random noise can falsify the measured RR-intervals up to 16 or 34 ms, respectively. These errors may be reduced to 1-4 ms with appropriate low pass filters. A frequency range of 0.5-20 Hz for the ECG amplifier can be sufficient for HRV analysis reducing the errors from AC interference or random noise.