275- What are the ECG abnormalities present in patients with TS?
The most common ECG abnormality present in patients with TS is sinus tachy-
cardia. Other abnormalities include right-axis deviation, QT prolongation, short
PR interval, and nonspecific T wave abnormalities.- What is the importance of pulse and blood pressure examination in patients
with TS?
Sinus tachycardia is common in patients with TS, which is due to dysautono-
mia and can be evident even during intrauterine period. Patients with TS having
sinus tachycardia are at increased risk of developing aortic dissection in the
presence of aortic dilatation. Radio-femoral delay is a clinical clue for the pres-
ence of coarctation of aorta. Blood pressure examination should be carried out
in all four limbs to detect the presence of coarctation of aorta.- What are the risk factors for aortic dissection in patients with TS?
Bicuspid aortic valve, coarctation of aorta, elongated transverse arch, aortic
dilatation, systemic hypertension, and sinus tachycardia are the risk factors for
aortic dissection in patients with TS. The predisposition for the development of
aortic dilatation/dissection is possibly due to abnormality in vascular collagen.- What is elongated transverse aortic arch?
Elongated transverse aortic arch (ETA) is one of the common cardiovascular
abnormalities present in patients with TS. ETA refers to the flattening of the aortic
arch with kinking along the lesser curvature, which is seen as increased distance
between the origins of left common carotid artery and left subclavian artery. ETA
can be well visualized on cardiac MRI and is present in 49 % of patients with TS.- How to define aortic dilatation?
The normal diameter of ascending aorta is between 20 and 37 mm. An aortic
diameter >4 cm is considered as aortic dilatation and surgical intervention are
indicated if diameter exceeds 5 cm. Patients with TS have lower body surface
area and smaller vasculature, hence, the aortic size is corrected for body surface
area, and aortic size index (ASI) is used for defining aortic dilatation. ASI is
calculated as diameter of ascending aorta (calculated at the level of right pul-
monary artery) divided by body surface area. An ASI >2 cm/m^2 warrants close
surveillance, while an ASI of >2.5 cm/m^2 warrants urgent referral for further
evaluation.8 Turner Syndrome