Supraventricular hypertension

Question 1

SVT

Answer 1

A regular narrow-complex tachycardia with no p waves and a super ventricular origin, atrioventricular nodal re-entry tachycardia (AVNRT) and atrioventricular re-entry tachycardia (AVRT)

Question 2

SVT AVNRT?

Answer 2

localised re-entry circuit around the AV node

Question 3

SVT AVRT?

Answer 3

a re-entry circuit forms between the atria and ventricles due to the presence of an accessory pathway (Bundle of Kent)

Question 4

SVT risk factors?

Answer 4

Nicotine, alcohol, caffeine, previous MI, digoxin toxicity.

Question 5

SVT epidemiology?

Answer 5

very common, females 2:1

Question 6

SVT symptoms?

Answer 6

minimal but can present with syncope, palpitations, light-headed, abrupt onset, fatigue, chest discomfort, dyspnoea, syncope.

Question 7

SVT Investigations ECG?

Answer 7

AVNRT appears normal, AVRT has delta waves

Question 8

SVT investigations others?

Answer 8

cardiac enzymes (for features of MI), electrolytes, TFTs, Digoxin level.

Question 9

SVT management?

Answer 9

if haemodynamically unstable – DC cardioversion, if stable, vagal monouevres + chemical cardioversion (adenosine)

Question 10

SVT complications?

Answer 10

haemodynamic collapse, DVT, systemic tamponade, systemic embolism