Cardiotocography is the most commonly used noninvasive diagnostic technique that provides physicians information about fetal development (in particular about development of autonomous nervous system - ANS) and wellbeing. . 2 years ago.
Bigeminy: Causes, symptoms, and treatments - Medical News Today No Comments . The fetuses with corrected transposition of the great arteries or ventricular rate70bpm had a better survival rate. The normal heart rate for a fetus is anywhere between 120 and 160 beats per minute.This is a rare condition, occurring in only 1-2% of pregnancies, and is normally a temporary, benign occurrence. Most are curable to a transplacental treatment by the first-line antiarrhythmic agents. In a non-randomized prospective study on 100 fetuses at 1540weeks of gestation for cardiac referal, 45 fetuses had cardiac arrhythmias, including premature atrial contractions (PACs) (28/45, 62.2%), atrial bigeminal ectopic beats (3/45, 6.7%), premature ventricular contractions (PVCs) (2, 4.4%), supraventricular tachycardia (SVT) (5/45, 11.1%), ventricular tachycardia (1, 2.2%), second-degree atrioventricular (AV) block (1, 2.2%) and complete AV block (5/45, 11.1%) [3]. Moreover, heart function and congenital heart defects exaggerate the severity of congestive heart failure [15]. Basically: The more you take care during the measurement, the lower the artifact probability! A gain-of-function TBX5 mutation is associated with atypical Holt-Oram syndrome and paroxysmal atrial fibrillation. For long VA SVT, the conversion rate to sinus rhythm did not differ significantly between the two drugs (67% vs. 50%, P=0.13). Less common but more fatal are those that cause low cardiac output, foetal hydrops and death. HHS Vulnerability Disclosure, Help https://doi.org/10.1186/s13052-020-0785-9, DOI: https://doi.org/10.1186/s13052-020-0785-9. Ishikawa T, Tsuji Y, Makita N. Inherited bradyarrhythmia: a diverse genetic background. Anyone you share the following link with will be able to read this content: Sorry, a shareable link is not currently available for this article. Keywords . 5,6 Heart rates less than 100bpm are classified as bradycardia, and rates greater than 180bpm are identified as tachycardia. 2015;79:85461.
Prophylactic Administration of Mesenchymal Stromal Cells Does Not Individualized treatment and clinical treatment should be determined according to specific types. 2020;13(2):267-273. doi: 10.3233/NPM-190268. These keywords were added by machine and not by the authors. Fetal Atrial Flutter Associated with Atrial Septal Aneurysm. Re: Sotalol as first-line treatment for fetal tachycardia and neonatal follow-up.
ECG-based machine-learning algorithms for heartbeat classification - Nature Objective: To assess whether noninvasive fetal electrocardiography (NI-FECG) enables the diagnosis of fetal arrhythmias. The FHR monitor acquires, processes, and displays an electronic signal. Aim: We aim to report a case of an enlarged fetal thymus causing arrhythmia. Shah et al. PubMed Central J Am Coll Cardiol. The overall mortality was 8%, only 4% of which was arrhythmia-related. Gembruch U, Hansmann M, Redel DA, Bald R. Intrauterine therapy of fetal tachyarrhythmias: intraperitoneal administration of antiarrhythmic drugs to the fetus in fetal tachyarrhythmias with severe hydrops fetalis. Yellow Raft unfolds with a distinctive rhythm as the reader moves backwards and forwards in time, encountering first the story of Rayona, then the story of her mother Christine, and finally the story of Aunt Ida, whose real relationship to the first two becomes one of the novels more powerful revelations. Respondek et al. The choice of vertical and horizontal scaling directly affects the appearance of the FHR and uterine contraction tracings. Miyoshi T, Maeno Y, Sago H, Inamura N, Yasukouchi S, Kawataki M, et al. Early delivery and direct ventricular pacing is a reasonable option when the fetal heart rate decreases progressively and hydrops fetalis develops in the presence of fetal AV block [15]. Prenatal Diagnosis of Fetal Heart Failure.
Treatment of Fetal and Neonatal Arrhythmias | USC Journal Prenat Diagn. Strizek et al. [54] described percutaneous transvenous intracardiac cardiac pacing performed in a case of fetal AV block via the fetal umbilical vein under ultrasound guidance.
Role of Maternal Artifact in Fetal Heart Rate Pattern Interp - LWW Fetal Arrhythmia Detection Using Fetal ECG Signal Pacing Clin Electrophysiol. Transplacental administration of steroids, such as dexamethasone and betamethasone, are effective for fetal AV block caused by positive maternal autoantibodies. Ultrasonic signals can penetrate human tissue. van der Heijden LB, Oudijk MA, Manten GT, ter Heide H, Pistorius L, Freund MW. Fetal Diagn Ther. Fetal heart rate and rhythm were measured by detecting semilunar and AV valve opening and closing points, A waves, plus ventricular wall motion. The anatomic M-mode provides simultaneous two-dimensional real-time images and therfore can obtain good quality tracings of atria and ventricles than by standard M-mode views. Debates remain regarding prenatal diagnosis and treatment of fetal arrhythmias. Capuruo et al. Both MCG and ECG may provide useful information on cardiac time intervals, such as the QRS and QT durations. The normal heart rate for a fetus is anywhere between 120 and 160 beats per minute.This is a rare condition, occurring in only 1-2% of pregnancies, and is normally a temporary, benign occurrence.
Artifacts vs. Arrhythmia - Autonom Health Both arrhythmia and dysrhythmia mean the same. Comparison of transplacental treatment of fetal supraventricular tachyarrhythmias with digoxin, flecainide, and sotalol: results of a nonrandomized multicenter study. Article and Reproductive Biology, 54:103108, M. L. Cabaniss, D. Karetnikov. Fetal bradycardia has shown limited therapeutic efficacy, and early treatment with steroids and/or plasmapheresis remains controversial. The received pattern is broken into very short second envelopes of time made up of 200 to 300 digitalized points (, As with first-generation monitors, interpretation of the FHR from newer monitors using autocorrelation must be done cautiously. DeVore GR, Horenstein J.
As the train passes and moves away, both loudness and pitch rapidly decline. https://doi.org/10.1007/978-3-540-73044-6_205, DOI: https://doi.org/10.1007/978-3-540-73044-6_205, Publisher Name: Springer, Berlin, Heidelberg, eBook Packages: EngineeringEngineering (R0).
Fetal Arrhythmia - American Pregnancy Association Phonocardiography was the first method used to record FHR electronically.
Fetal Arrhythmia and Dysrhythmia Facts and Treatments - Lifespan 2018;219:3205. For fetuses with hydrops, the placental transfer of the digoxin is limited. The literature reporting on prenatal diagnosis and treatment of fetal arrhythmias published in the recent two decades were retrieved, collected and analyzed. The highest point of the waveform is detected and recorded as a heart beat, even though it may not appear at the same time in each waveform. Diagnosis and management of fetal bradyarrhytmias. The principles underlying the use of Doppler FHR monitoring are described. 1):167269. In 2 fetuses of their patient setting, the arrhythmias were diagnosed using two-dimensional echo alone. Assessment of such artifacts and of the hemodynamic relevance of a fetal arrhythmia by alternative methods is necessary for management and therapy. In this article, the clinical diagnosis and treatment of fetal arrhythmias are presented, and advantages and disadvantages of antiarrhythmic agents for fetal arrhythmias are compared. Am J Obstet Gynecol. ted. The clinical outcome and prognosis of patients are usually determined by the type and extent of cardiac malformation [55]. Oudijk MA, Visser GH, Meijboom EJ. Detection of fetal motion with Doppler signal is the same with both the older and newer monitors. 2023 Feb 18;13(4):779. doi: 10.3390/diagnostics13040779. Jaeggi ET, Nii M. Fetal Brady- and tachyarrhythmias: new and accepted diagnostic and treatment methods. ; ; . Federal government websites often end in .gov or .mil. PubMed The outcomes of intrauterine therapy of fetal tachyarrhythmias depend on the types or etiology of fetal arrhythmias and fetal conditions. Manage cookies/Do not sell my data we use in the preference centre. fetal arrhythmia vs artifactdiscretionary housing payment hackney. Treatment success was defined as conversion to sinus rhythm, or rate control, defined as >15% rate reduction [14]. Sotalol and flecainide have good placental transfer ability, and they should be used as first-line treatment for hydropic fetal tachyrrhythmias. Cite this article.
Cardiac arrhythmias and artifacts in fetal heart rate signals J Matern Fetal Neonatal Med. To understand the significance of the FHR display, it is important to understand what the monitor can and cannot count. Provided by the Springer Nature SharedIt content-sharing initiative. Therefore, prenatal treatment is warranted for improving the fetal survival rate. Uterine tachsystole. For AF persisting for 5days, flecainide use achieved a much better heart rate control than soltalol [35]. Zhi-Yang Xu. and how to discover that. Novii provides the opportunity to enhance your current Labor and Delivery monitoring experience. 2018;11:349.
fetal arrhythmia vs artifact - chamberlainfunding.com The mechanisms of fetal bradycardia were complete AV block (14/29, 48.3%), second-degree AV block (8/19, 42.1%). It is the process of signal conversion to FHR that differs. Fetal arrhythmias: premature atrial contractions and supraventricular tachycardia. Your doctor may discover this anomaly when doing a routine ultrasound or listening to your baby's . The intrauterine or neonatal mortality rate in hydropic fetuses treated with flecainide was much lower than that treated with digoxin (0% vs. 43%, P=0.06). For fetuses with hydrops and fetal SVT with long VA interval, digoxin is rarely effective. There are other rare types of fetal arrhythmias, such as ventricular tachycardia, junctional tachycardia, and multiforcal atrial tachycardia [14]. The fetuses with benign arrhythmias, such as PACs <11 beats per minute (bpm) and sinusal tachycardias, did not need any treatment before or after birth, whereas those with postnatal arrhythmias associated with hemodynamic fluctuations require interventions, as they may lead to preterm delivery in some occasions [9]. ____ denotes the spontaneous, rhythmic depolarization of cardiac cells. 2018;31:40712. Use this EKG interpretation cheat sheet that summarizes all heart arrhythmias in an easy-to-understand fashion. AlSoufi M. Successful treatment of fetal tachycardia by sotalol. volume46, Articlenumber:21 (2020) J Arrhythm. 2002;17:757. J Ultrasound Med. Maeno Y, Hirose A, Kanbe T, Hori D. Fetal arrhythmia: prenatal diagnosis and perinatal management. Springer Nature. Capuruo et al. This section will deal with the methodology involved in the clinical application of these techniques. Sotalol as an effective adjunct therapy in the management of supraventricular tachycardia induced fetal hydrops fetalis. & Gynecol. The impact of intrauterine treatment on fetal tachycardia: a nationwide survey in Japan. and transmitted securely. 4 Normal fetal heart rates range from 120-160bpm at 30 weeks' gestation and 110-150bpm at term. J Obstet Gynaecol Res. Fetal cardiac rhythm abnormalities are common and are encountered in about 1% to 2% of pregnancies ( 1 ). B. Maternal hypotension. Yaksh A, van der Does LJME, Lanters EAH, de Groot NMS. The mechanisms of SVT can be classified as mechanical VA intervals as short VA or long VA [14]. Pascals law dictates that assuming such a monitoring system is a closed system, the baseline tone as well as the intrauterine pressure during a contraction will be transmitted directly to the external strain gauge pressure transducer. 2004;52:13847. It is more effective than digoxin, especially for hydropic fetal tachycardia, with no adverse fetal outcomes found [14]. Both, artifacts and cardiac arrhythmias represent outliers of the FHR signals, so they affect both time domain and time frequency signal analysis. Fetal arrhythmia is rare. [9] reported that PACs were the most common fetal arrhythmias representing 55.5% (100/180), followed by bi- or trigemy (12/180, 0.7%), sinus tachycardia (18.3%, 33/180), SVT (15.6%, 28/180), and AF 0.4% (7/180). It was regarded as a reentrant tachycardia through a fast-conducting AV accessory pathway. 2011;38:40612. Both M-mode and Doppler echocardiography can help diagnose sinus bradycardia. Epub 2012 Mar 22. Bigeminy does not always cause symptoms. Abb. After the pacing wire was advanced into the right atrium and subsequently the right ventricle, the pacing rate was set up at 140bpm. BMJ Open. Fetal intraperitoneal amiodarone was successful in 75% (6/8) cases. PMC 1,7. J Cardiol Curr Res. Rev Med Suisse. 2018;257:1607. [41] Freedom from arrhythmia on maintenance therapy was 93 and 90% at 1 and 3months, respectively. Therefore, when fetal arrhythmia, in particular fetal bradycardia, is found, special attention should be paid to whether cardiac structural abnormalities is present [55].
Novii Wireless Patch System - GE Healthcare Clinically, uterine contractions can be monitored by two techniques: external tocodynamometry or intrauterine pressure measurement. Alvarez A, Vial Y, Mivelaz Y, Di Bernardo S, Sekarski N, Meijboom EJ. Fetal cardiac pacings are effective methods to restore sinus rhythm in drug-resistant or hemodynamically compromised cases.
Artifacts vs dysrhythmias.docx - Describe the role of each Fetal bradycardia with either congenital heart defects or fetal hydrops significantly worsens their prognoses. Fetal heart arrhythmias and doppler ultrasound. Population ageing is a severe demographical challenge in the near future.
fetal arrhythmia vs artifact - quickfundinggroup.com Thus, it is not helpful in diagnosing fetal rhythm and conduction disorders with irregular heart rates.
Maternal or Fetal Heart Rate? Avoiding Intrapartum Misidentification 2016;5:414. Stirnemann et al. The neonatal and overall survival rates for fetal bradyarrhythmia with structural heart disease were much higher, which were 66 and 48%, respectively. Open Access This article is distributed under the terms of the Creative Commons Attribution 4.0 International License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution, and reproduction in any medium, provided you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made. This occurs only with fetal supraventricular tachyarrhythmias (paroxysmal atrial tachycardia, atrial fibrillation, or atrial flutter), intermittent premature atrial contractions (PACs), or premature ventricular contractions (PVCs) (, An additional instance that may cause confusion is the patient with a cardiac pacemaker.
These arrhythmias do not represent an expression of the physiological behavior of the ANS. Fetal arrhythmias. PHONOCARDIOGRAPHICALLY DERIVED FETAL HEART RATE. D. Maternal fever. 8,12,16 The use of fetal echocardiography, M-mode and pulse-wave Doppler has lead to improved diagnosis of fetal arrhythmias, and remains the cornerstone of diagnosis. Donofrio MT, Gullquist SD, Mehta ID, Moskowitz WB. Uterine contraction intensities. If the interface is moving, the reflected signal undergoes a frequency change (Doppler shift). Article 2018;122:A20644. Keywords: 1993;12:66971. Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations. Can digoxin and sotalol therapy for fetal supraventricular tachycardia and hydrops be successful? Regular screening by fetal echocardiography and transplacental treatment could prevent this risk factor [9]. Hajdu J, Pete B, Harmath A, Varadi V, Papp Z. Fetal arrhythmias: a clinical review. PubMed Central Suri V, Keepanaseril A, Aggarwal N, Vijayvergiya R. Diagnostics (Basel). According to an article in the Indian Pacing and Electrophysiology Journal , the normal fetal heart rate ranges between 110 and 160 beats . 1985;8:110. Sustained fetal arrhythmias associated with major structural heart disorders, hydrops fetalis, and fetal heart failure warrant intrauterine pharmaceutical conversion of heart rhythm or early pacemaker implant in order to avoid fetal demise. Fetal bradyarrhythmia associated with congenital heart defects - nationwide survey in Japan. fetal arrhythmia vs artifact.
Diagnosis and Treatment of Fetal Tachyarrhythmias Digoxin, flecainide and sotalol can be the first-line treatments. Carpenter RJ Jr, Strasburger JF, Garson A Jr, Smith RT, Deter RL, Engelhardt HT Jr. Fetal ventricular pacing for hydrops secondary to complete atrioventricular block. (2007). M-mode and pulsed Doppler ultrasound assessment of severe fetal bradycardia. Oral flecainide (100mg three times daily) is reserved for those cases unresponsive to sotalol and digoxin [34]. Hydrostatic pressure within the uterus should be equal at all points. Immediate postnatal pacemaker implantation is warranted in refractory cases. A case report. Ultrasound Med Biol.
Spatial and temporal immunoreaction of nestin, CD44, collagen IX and The sustained PVCs may also resolve within 6weeks, and do not cause severe arrhythmias [24]. Immediate appointments are often available.
Fetal Arrhythmia: Causes and Treatment - Healthline 11th Mediterranean Conference on Medical and Biomedical Engineering and Computing 2007 pp 789792Cite as, Part of the IFMBE Proceedings book series (IFMBE,volume 16). Among other causes, the fetal arrhythmia is accountable for a significant portion of such . Article statement and [13] reported that they used a two-dimensional scan head with M-mode recordings for the diagnosis of fetal arrhythmias. This signal can then be used as a marker of the fetal heart beat as well as for the creation of fetal heart sounds produced by the monitor. Blocked atrial bigeminy also resembles 2:1 AV block and causes fetal bradycardia.
Gen. Ed Prof Ed. Refresher Rviews | PDF | Teachers | Leadership Appropriate clinical measures should be taken into consideration with regard to outcomes and prognosis. The fetal thymus is a structure that usually goes unnoticed during the process of prenatal diagnosis, and when it presents alterations in its morphology, can lead to confusion and cause fetal arrhythmias without an adverse clinical outcome. A 28-year-old healthy woman was referred at 30 weeks of gestation because of fetal tachy-brady-arrhythmia, but cw-Doppler assessment of umbilical artery blood flow revealed periods of . The site is secure. Sustained arrhythmias may be associated with heart failure, however, manifesting as nonimmune hydrops fetalis. Clinical presentation, management, and postnatal outcomes of fetal tachyarrhythmias: a 10-year single-center experience. Zhang W, Dai X, Liu H, Li L, Zhou S, Zhu Q, Chen J. Ultrasound Obstet Gynecol. By using Doppler ultrasound, simultaneous recordings of the atrial and ventricular waves can be obtained.
Contribution of Fetal Magnetocardiography to Diagnosis, Risk Assessment The aim of the present study is to discuss the complex and challenging issue concerning the prenatal evaluation and intrauterine therapeutics of fetal arrhythmias. fetal arrhythmia vs artifact. Clipboard, Search History, and several other advanced features are temporarily unavailable. Hosono T, Kanagawa T, Chiba Y, Neki R, Kandori A, Tsukada K. Fetal atrial flutter recorded prenatally by magnetocardiography. In PACs, extra heartbeats can come from the top of the heart, separate from the sinus node. It also extracts 16 significant features from multiple domains, including (time, frequency, and time-frequency features. Strizek B, Berg C, Gottschalk I, Herberg U, Geipel A, Gembruch U. High-dose flecainide is the most effective treatment of fetal supraventricular tachycardia. Flecainide is highly effective in achieving sinus rhythm in hydropic and nonhydropic fetuses with SVT, refractory SVT or SVT with signs of heart failure. National Library of Medicine Lin AE, O'Brien B, Demmer LA, Almeda KK, Blanco CL, Glasow PF, et al. Fetal tachycardia is a faster heart rate than expected. The overall incidence of malignant fetal arrhythmias, such as complete AV block and SVT, are relatively rare, found in 1:5000 pregnancies [5]. Part of Fetal cardiac pacings are effective methods to restore sinus rhythm in drug-resistant or hemodynamically compromised cases. by | Jun 10, 2022 | north river road, ottawa | texas roadhouse fundraiser rolls directions | Jun 10, 2022 | north river road, ottawa | texas roadhouse fundraiser rolls directions Sinus bradycardias are often caused by fetal hypoxia or immaturity of the cardiac conduction system. van der Heijden LB, Oudijk MA, Manten GT, ter Heide H, Pistorius L, Freund MW. IFMBE Proceedings, vol 16. vol. Flecainide was preferred in converting SVT to normal sinus rhythm or in slowing AF to well-tolerated ventricular rates [35]. 8600 Rockville Pike 1994;9:1835. For this reason, a manual gain control offers a great advantage when using abdominal fetal phonocardiography for recording heart rate. This safe, noninvasive test shows the structure of the heart and helps determine the type of arrhythmia. Pacing Clin Electrophysiol. Christoffels VM, Moorman AF. Miyoshi et al. This management usually takes place during the second or third trimester. 2022 Nov 23;10:1012600. doi: 10.3389/fped.2022.1012600. Flecainide versus digoxin for fetal supraventricular tachycardia: comparison of two drug treatment protocols. Also, because of the high sensitivity to ambient noise, the technique is unsatisfactory for monitoring during the active phase of labor (. The majority of fetal arrhythmias are premature contractions. J Matern Fetal Neonatal Med. A premature atrial contraction, or PAC, is by far the most common arrhythmia we see. Maternal anti-SSA/SSB antibody positivity is another cause of fetal AV block.
Myoinositol reduction in medial prefrontal cortex of obsessive Fetal arrhythmia is a term that refers to any abnormality in the heart rate of your baby. Flecanide and sotalol cross the placental barrier easier, especially in hydropic fetuses, and a higher drug concentration can be achieved in the amniotic fluid. A. Stimulation of fetal chemoreceptors. Unable to load your collection due to an error, Unable to load your delegates due to an error. By using Doppler ultrasound, simultaneous recording of the atrial and ventricular waves can be obtained. Bigeminy is a type of heart arrhythmia in which the heart beats once normally and once abnormally in quick succession, followed by a pause. It can be helpful in making prenatal diagnoses of a variety of fetal arrhythmias, such as complete AV block, premature contractions, paroxysmal SVT and Wolff-Parkinson-White syndrome and long QT syndrome [19]. Tutschek B, Schmidt KG. PACs are usually benign and often resolve spontaneously, but follow-up is necessary for preventing from developing into ventricular tachycardia [22]. Terms and Conditions, The angle of reflection varies according to the angle of incidence of the beam.
Noninvasive fetal electrocardiography for the detection of fetal 2013;42:28593. A portion of the signal will be transmitted to the next interface. In nonhydropic fetuses, the successful rate of flecainide was higher than digoxin (96% vs. 79%, P=0.10). van der Heijden LB, Oudijk MA, Manten G, ter Heide H, Pistorius H, Freund MW. Characterization of fetal arrhythmias by means of fetal magnetocardiography in three cases of difficult ultrasonographic imaging. Both, artifacts and cardiac arrhythmias represent outliers of the FHR signals, so they affect both time domain and time frequency signal analysis. Assessment of fetal arrhythmia by simultaneous Doppler recording of flow patterns in the ascending aorta and superior vena cava. 2017;9:00322 http://medcraveonline.com/JCCR/JCCR-09-00322.php. 2021 Oct;10(10):2432-2438. doi: 10.21037/tp-21-233. 2016;48(Suppl. MeSH The original electrode was a modified skin clip, but now a spiral electrode is used. J Am Heart Assoc. Debates remain regarding prenatal diagnosis and treatment of fetal arrhythmias. This article reviews heart rate monitoring . Intrauterine pressure has historically been determined with the use of an open-ended, fluid-filled catheter placed through the cervix and externally attached to a strain gauge transducer. The time to conversion to sinus rhythm for sotalol varied from 1 to 5days (median 1day) for Shah et al. In 2 cases, maternal QRS complexes which were detectable at the fetal scalp electrode were counted, resulting in misleading recordings. Ultrasound Obstet Gynecol. Most are brief, fleeting occurrences of slow or fast heartbeat or irregular heart rhythm. Figure 4.4. To remove noise and artifacts, the . PubMed Fetal arrhythmias are a common phenomenon with rather complicated etiologies. In addition, the actual signal created by the fetal cardiac motion is greatly affected by the position and movement of the transducer with respect to the fetus. In long VA tachycardia, an A wave of normal amplitude with normal AV time interval could be detected in front of the aortic ejection wave [16]. Google Scholar. Successful in utero transesophageal pacing for severe drug-resistant tachyarrhythmia. Crisan CD, Lighezan I, Lazar E, Moscu AV.
fetal arrhythmia vs artifact - waterfresh.gr Fetal complete AV block with structural heart disease often shows a worse prognosis, such as fetal demise or pacemaker implant requirement. Long QT syndrome can cause 2:1 AV block or sinus bradycardia. Irregular fetal cardiac rhythm is the leading cause for referrals to fetal echocardiography centers for rhythm disturbances, and the vast majority of those are benign atrial ectopic beats. C. Umbilical vein compression. External monitoring using various biophysical modalities has. These can include tachycardia-an increased heart rate-or bradycardia, which is a slowed heartbeat. Both, artifacts and cardiac arrhythmias represent outliers of the FHR signals, so they affect both time domain and time frequency signal analysis. Most of the rapid fetal arrhythmia is a nonorganic lesion, mostly transient.