Cyanosis screening

Revision as of 17:43, 11 March 2018 by Medhat (talk | contribs)
Jump to navigation Jump to search

Cyanosis Microchapters

Home

Overview

Historical Perspective

Classification

Pathophysiology

Causes

Differentiating Cyanosis from other Diseases

Epidemiology and Demographics

Risk Factors

Screening

Natural History, Complications and Prognosis

Diagnosis

Diagnostic Study of Choice

History and Symptoms

Physical Examination

Laboratory Findings

Electrocardiogram

Chest X Ray

CT

MRI

Other Imaging Findings

Other Diagnostic Studies

Treatment

Medical Therapy

Surgery

Primary Prevention

Secondary Prevention

Cost-Effectiveness of Therapy

Future or Investigational Therapies

Case Studies

Case #1

Cyanosis screening On the Web

Most recent articles

Most cited articles

Review articles

CME Programs

Powerpoint slides

Images

American Roentgen Ray Society Images of Cyanosis screening

All Images
X-rays
Echo & Ultrasound
CT Images
MRI

Ongoing Trials at Clinical Trials.gov

US National Guidelines Clearinghouse

NICE Guidance

FDA on Cyanosis screening

CDC on Cyanosis screening

Cyanosis screening in the news

Blogs on Cyanosis screening

Directions to Hospitals Treating Cyanosis

Risk calculators and risk factors for Cyanosis screening

Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1]; Associate Editor(s)-in-Chief:

Overview

Screening

In 2014, a guideline for the performance of fetal echocardiography was published by the AHA with multidisciplinary input [14].

Guidelines for the performance of fetal echocardiograms are also available from the International Society for Ultrasound in Obstetrics and Gynecology [30], and from the American Institute for Ultrasound in Medicine [31].

  • Ultrasound systems used for fetal echocardiography [32]
  • Color Doppler are used to identify small vessels such as the pulmonary veins, ductus venosus, and ductus arteriosus, to assess valvular competence and flow patterns, and to examine the ventricular septum for defects. M-mode of atrial and ventricular wall motion can be useful for analyzing rate and rhythm disturbances.
  • More advanced imaging techniques, which are beyond the scope of this review, include three-dimensional and four-dimensional echocardiography, tissue Doppler, strain and strain rate imaging, fetal electrocardiography, fetal magnetocardiography, and cardiovascular magnetic resonance imaging [14].
  • The sonographic appearance of specific anomalies is beyond the scope of this topic, but can be found in UpToDate topics on specific anomalies.
  • When a fetal cardiac abnormality is detected, additional evaluation and follow-up are indicated. Patients who have a normal basic fetal cardiac evaluation and echocardiography (if performed) generally do not require further evaluation unless there is an elevated risk of evolution of fetal heart disease later in pregnancy.
  • The identification of a fetal cardiac defect should prompt a thorough search for extracardiac abnormalities, since these are detected in at least 20 to 40 percent of cases, depending on the population (eg, midtrimester fetuses versus liveborns versus liveborns and stillborns) [33-35]. Furthermore, cardiac anomalies are part of numerous fetal syndromes [36,37]. An analysis of data compiled from 20 registries of congenital malformations reported that approximately 4 percent of the patients with cardiac anomalies had an identifiable syndrome [37].
  • Congenital heart disease is associated with an increased risk for adverse neurodevelopmental outcome, which has been attributed to factors such as associated chromosomal abnormalities, syndromes, postnatal cardiac dysfunction, perioperative factors in infants who require surgical treatment, and possibly in utero hemodynamic abnormalities. In children with isolated cardiac abnormalities, the frequency of neurodevelopment development also depends on the specific abnormality. (See "Management and outcome of tetralogy of Fallot", section on 'Neurodevelopmental outcome and quality of life' and "Management and outcome of D-transposition of the great arteries", section on 'Neurodevelopmental and psychiatric outcome' and "Management of patients post-Fontan procedure", section on 'Functional, developmental, and psychiatric disorders' and "Hypoplastic left heart syndrome: Management and outcome", section on 'Neurodevelopmental outcome'.)
  • Prenatal neuroimaging findings are generally not predictive of postnatal neurodevelopmental outcome. A systematic review and meta-analysis of studies of prenatal ultrasound and magnetic resonance imaging (MRI) found that brain abnormalities, delay in head growth, and brain-sparing were observed in subgroups of fetuses with congenital heart disease [38]. However, the prognostic significance of these findings was unclear because large MRI studies were scarce, ultrasound data were biased towards severe and left-sided heart abnormalities, and long-term follow-up studies correlating prenatal and postnatal findings were limited.

Genetic assessment

Fetal genetic assessment is indicated because chromosome abnormalities are common in fetuses with cardiac defects, even when isolated (table 3) [22,35,39-42]. In one series of 1510 fetuses with prenatally diagnosed structural cardiac defects, 624 (41 percent) had an abnormal karyotype (aneuploidy in 562 cases, structural chromosomal abnormalities in 62 cases) [43]. This incidence is higher than in infants with congenital heart disease (incidence about 15 percent [44]) because of in utero mortality in many cases, such as the lethal autosomal trisomies (eg, trisomy 9 or 16).

The risk of fetal aneuploidy varies depending on the malformation. For example (risk percent) [14]:

●Atrioventricular septal defect (46 to 73 percent)

●Truncus arteriosus (19 to 78 percent)

●Double-outlet right ventricle/conotruncal malformations (6 to 43 percent)

●Coarctation/arch interruption (5 to 37 percent)

●Tricuspid valve dysplasia (including Ebstein malformation, 4 to 16 percent)

●Tetralogy of Fallot (7 to 39 percent)

●Hypoplastic left heart syndrome (HLHS, 4 to 9 percent)

●Pulmonic stenosis/atresia with intact ventricular septum (1 to 12 percent)

●Heterotaxy/cardiosplenic syndromes (0 percent)

●Transposition of great arteries (0 percent)

In addition, the 22q11 deletion has been associated with several cardiac anomalies, including interrupted aortic arch, truncus arteriosus, ventricular septal defect, and tetralogy of Fallot [14]. (See "DiGeorge (22q11.2 deletion) syndrome: Clinical features and diagnosis".)

The two main approaches for genetic testing are (1) G-banding of fetal cells obtained via amniocentesis, with fluorescent in situ hybridization (FISH) to assess for microdeletions, such as 22q11, not detectable by visual banding techniques, and (2) chromosomal microarray, which detects submicroscopic chromosomal abnormalities in 5 percent of fetuses with ultrasound-detected anomalies and a normal G-band karyotype. Disadvantages of chromosomal microarray are that balanced rearrangements are not detectable and variants of unknown significance may be identified. Either approach is reasonable; the best choice is controversial and depends on factors such as physician/patient preference, cost, suspicion of trisomy or balanced rearrangement versus a microscopic gene defect, and time to obtain definitive results. (See "Use of chromosomal microarray in obstetrics".)

If these tests are normal and there is a family history of a similar cardiac defect, long QT syndrome, or Noonan syndrome, DNA mutation analysis and direct sequence analysis are options. (See "Congenital long QT syndrome: Diagnosis" and "Causes of short stature", section on 'Noonan syndrome'.)

References

Template:WH Template:WS