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prevalence may be as high as 146 per 100 000. It is characterized by a male preponderance of eight or
nine to one. The ECG anomaly is characteristic of the syndrome and tends to vacillate. In the type 1 form,
there is coved upward ST segment elevation with a J wave amplitude >0.2mV followed by an inverted T
wave in V1 and V2 (the Brugada sign). Less striking abnormalities are seen in types 2 and 3. The
tendency to mimic right bundle branch aberration and its variability may give rise to interpretative
difficulties.
The QT interval may be normal or slightly prolonged. It is rare in the pilot population, having a
prevalence of 0.08 per cent in 16 988 French Air Force personnel. This was increased by a further 0.05
per cent following challenge with ajmaline. Of 334 Brugada phenotypes in one study, the pattern was
recognized in 71 subjects following resuscitation after a cardiac arrest, in 73 subjects following a
syncopal event, and was recorded in a further 190 asymptomatic individuals. See Appendix 1b: 15. In a
recent report, in 2,479 Finnish aircrew applicants, morphological ECG changes similar to, but not
diagnostic of the Brugada pattern (eg type 2 and 3) had a normal outcome. Pedro Brugada has also
expressed concern that the sign is being over-reported.
Long QT syndrome (LQTS) may be congenital or acquired. It is characterized by an abnormality of
myocardial depolarisation: either sodium or potassium channels may be involved. In the congenital form,
it used to be known as the Romano-Ward syndrome4 or, if associated with nerve deafness, as the Jervell
1 Lenègre’s disease: aquired complete heart block due to primary degeneration of the conduction system. After Jean
Lenègre, French cardiologist (1904-1972).
2 Torsades de pointes: an atypical rapid ventricular tachycardia with periodic waxing and waning of amplitude of
the QRS complexes on ECG and rotation of the complexes around the isoelectric line (Fr. “fringe of pointed tips”).
3 Brugada syndrome: genetic disease characterized by right bundle branch block, ST segment elevation in V1 to V3
and sudden death, also a cause of the Sudden Arrhythmic Death Syndrome (SADS). The syndrome or rather
disease is the most common cause of sudden death in young men without known underlying cardiac disease. After
the brothers Pedro, Josep and Ramón Brugada, Spanish cardiologists, who described the disease in 1992.
4 After C. Romano, Italian physician, and O.C. Ward, Irish physician (20th century).
ICAO Preliminary Unedited Version — October 2008 III-1-30
and Lange-Nielsen syndrome1. Eight different genotypes and six different phenotypes (LQT1 - 6) have
been identified. In all, there is an increased risk of syncope, ventricular tachycardia (torsades de pointes)
and sudden cardiac death. The T waves are bizarre and the QT interval often significantly prolonged
(> 550ms (normal < 440ms in males, < 460ms in females)). Nevertheless, 30 per cent of carriers of the
gene have a normal QT interval.
Outcome is related to the length of the QTc (Bazett’s formula2), the genotype, and the presence or
absence of complex ventricular rhythm disturbances including the characteristic torsades de pointes
tachycardia. Acquired prolongation of the QT interval can occur in electrolyte disturbance
(hypocalcaemia, hypomagnesaemia), metabolic disturbance (myxoedema) and drug administration
(including quinidine, amiodarone, sotalol, phenothiazines and tricyclics, erythromycin, quinine,
chloroquine, ketanserin, cisapride, terfenadine, tacrolimus and probucol). Hypokalaemia increases the risk
of event.
One of the problems with both syndromes is the overlap with the normal ECG. Fifty per cent of LQT
carriers are asymptomatic although up to four per cent may die suddenly. The LQT3 phenotype is the
most lethal and LQT1 the least. A QTc >500ms powerfully predicts an unfavourable outcome and such
people should not be certificated. Initial issue of a Medical Assessment in the future may require
genotyping for this condition. If the condition is confirmed, certification is likely to be denied. LQT1 and
LQT2 phenotypes in females and LQT3 phenotype in males are particularly adverse findings
In the absence of genotyping, likely candidates for certification with the LQTS or the Brugada syndrome
will:
• be asymptomatic
• have no family history of sudden cardiac death (SCD)
• have minimal ECG features or features seen only intermittently or following pharmacological
provocation
• have no evidence of complex ventricular rhythm disturbance on regular Holter monitoring.
• be restricted to multi-crew operations
ENDOCARDIAL PACEMAKING
Conditions requiring the implantation of an endocardial pacemaker are uncommon in candidates of
　
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