Specimen:

Plasma

Collection Medium:

Minimum:

Two 4 mL lavendar top tubes

Delivery Instructions:

Submit specimen to laboratory as soon as possible after collection.

Specimen
Instructions:

Draw Monday-Thursday only.

Analytic Time:

4-6 weeks

Reference Range:

See report

Comments:

Genetic analysis is very important for identifying all mutation 
carriers within the LQTS family.  Once identified, silent carriers of 
LQTS genetic defects may be treated with beta-blockers for prophylaxis 
of life-threatening arrhythmias.  Furthermore, silent mutation carriers 
should receive genetic counseling to learn about the risk of 
transmitting LQTS to offspring.

In patients affects by LQTS, genetic analysis is useful for risk 
stratification and for making therapeutic decisions.

Risk Stratification
   *Genetic testing is often useful in probands with a clinical
    diagnosis of LQTS to provide more accurate risk stratification
    and to guide therapeutic strategies.

   *It has been shown that the interplay between genetic defect,
    QT duration, and gender may provide an algorithm for risk
    stratification.

Genetic testing that can detect a mutation which may cause cardiac 
channelopathies, rare, potentially lethal heart conditions.  The tests 
can reduce uncertainty and find the specific causes of cardiac 
channelopathies, the test can:
  *Help diagnose a patient's disease
  *Guide treatment options
  *Determine whether family members are at risk

Patients presenting with:
-Unexplained syncope
-Onset of symptoms typically occurs during childhood and adolescence
-Family Hx of sudden cardiac death
-Unexplained VT/VF or TdP
-Prolonged QT interval

KCNQ1 (LQT1)
KCNH2 (LQT1)
SCN5A (LQT3)
KCNE1 (LQTS)
KCNE2 (LQT6)

Please print, complete and submit the Test Requisition and Informed 
Consent for Testing from PGxHEALTH with the A-1a Miscellaneous 
Request.

CPT Code:

83912, 83891, 83898(x73), 83904(x73), 83909(x73)