Jervell and Lange-Nielsen Syn... Health Article

Preventative measures

All individuals who have been diagnosed with JLNS must avoid reductions in blood potassium levels, such as those that occur with the use of diuretics (drugs that reduce fluids in the body). People with JLNS must also avoid a very long list of drugs and medications that can increase the QT interval or otherwise exacerbate the syndrome.

People with JLNS usually are advised to refrain from competitive sports and to practice a "buddy system" during moderate exercise. Family members are advised to learn cardiopulmonary resuscitation (CPR) in case of cardiac arrest.

Prognosis

Cochlear implants may improve the hearing of people with JLNS. The cardiac abnormalities of JLNS usually can be controlled with beta-blockers. However, without treatment, there is a high incidence of sudden death due to cardiac events.

Family members of a JLNS individual should be screened with ECGs/EKGs for a prolonged QT interval, since they are at risk of having LQTS. Genetic counseling is recommended for people with JLNS, since their children will inherit a gene causing LQTS.

PERIODICALS

Chen, Q., et al. "Homozygous Deletion in KVLQT1 Associated with Jervell and Lange-Nielsen Syndrome." Circulation 99 (1999): 1344-47.

Schmitt, N., et al. "A Recessive C-terminal Jervell and Lange-Nielsen Mutation of the KCNQ1 Channel Impairs Subunit Assembly." The EMBO Journal 19 (2000): 332-40.

Steel, Karen P. "The Benefits of Recycling." Science 285 (August 27, 1999): 1363-1364.

ORGANIZATIONS

American Heart Association. 7272 Greenville Ave., Dallas, TX 75231-4596. (214) 373-6300 or (800) 242-8721. inquire@heart.org. <http://www.americanheart.org>.

American Society for Deaf Children. PO Box 3355, Gettysburg, PA 17325. (800) 942-ASDC or (717) 334-7922 v/tty. <http://www.deafchildren.org/asdc2k/home/home.shtml>.

Deafness Research Foundation. 575 Fifth Ave., 11th Floor, New York, NY 10017. (800) 535-3323. drf@drf.org.

EAR (Education and Auditory Research) Foundation. 1817 Patterson St., Nashville, TN 37203. (800) 545-HEAR. earfound@earfoundation.org. <http://www.theearfound.org>.

European Long QT Syndrome Information Center. Ronnerweg 2, Nidau, 2560. Switzerland 04(132) 331-5835. jmettler@bielnews.ch. <http://www.bielnews.ch/cyberhouse/qt/qt.html>.

Sudden Arrhythmia Death Syndrome Foundation. PO Box 58767, 508 East South Temple, Suite 20, Salt Lake City, UT 84102. (800) 786-7723. sads@sads.org. <http://www.sads.org>.

WEBSITES

Contie, Victoria L. "Genetic Findings Help Tame the Runaway Heart." NCAA Reporter, [November-December 1997]. <http://www.ncrr.nih.gov/newspub/nov97rpt/heart.htm>

"Genetics of Long QT Syndrome/Cardiac Arrest." DNA Sciences. 2001. <http://my.webmd.com/content/article/3204.676>

Long QT Syndrome European Information Center. <http://www.qtsyndrome.ch/lqts.html>

Narchi, Hassib, and Walter W. Tunnessen Jr. "Denouement and Discussion: Jervell and Lange-Nielsen Syndrome (Long QT Syndrome)." Archives of Pediatrics and Adolescent Medicine, 153, no. 4 (April 1999). <http://archpedi.ama-assn.org/issues/v153n4/ffull/ppm8451-1b.html>

Margaret Alic, PhD