Narrow complex tachycardia

Cardiology, internal medicine

1. Narrowcomplextachycardia
Domina Petric, MD

2. Definition
•Heartrate >100 bpm!
•QRS duration<120 ms!
Imagesource: Lifeinthefastlane.com

3. Typesoftachycardia
Sinus tachycardia: normal P wave
followed by normal QRS.
Supraventriculartachycardia
(SVT): P waveabsentor inverted
afterQRS.

4. Typesoftachycardia
•Atrialfibrillation: absentP wave,
irregularQRS complexes.
•Atrialflutter: atrialrate usually300 bpm
withflutterwaves(sawtooth), ventricular
rate 150 bpm(2:1 block).
•Atrialtachycardia: abnormallyshapedP
waves, mayoutnumberQRS complexes.

5. Typesoftachycardia
•Multifocalatrialtachycardia: three
or more P wavemorphologies,
irregularQRS complexes.
•Junctionaltachycardia: rate 150-
250 bpm, P waveeaitherburiedin
QRS complexor occurringafter
QRS complex.

6. Management ofSVT
Vagalmanoeuvres:
•breathholding
•valsalvamanoeuvre
•carotidmassage

7. Management ofSVT
Vagalmanoeuvrescanbe
usedonlyifthepatientis
haemodynamically
stable.

8. Management ofSVT
Adenosineiv. is nextstep:
•6 mg iv. bolusintoa bigvein
•salineflush
•recordinga rhythmstrip
•after1-2 min, 12 mg iv. ifnecessary

9. Adenosine
•Side effectsare transientchesttightness,
dyspnoea, headacheandflushing.
•Contraindications: asthmaAV blockof
secondandthirddegree, sinoatrial
disease(withoutpacemaker).
•Importantdrug interactions:
dipyridamoleincreaselevels,
theophyllineantagonisesadenosine.

10. Management ofSVT
•Ifadenosineis noteffective, verapamil
canbeusedindoseof5 mg iv. over2
minutes(over3minutesinelderly).
•Verapamilcannotbeusedifthepatient
is takingbeta blockers.
•Ifthereis no response, doseof5 mg iv.
canberepeatedafter5-10 minutes.

11. Management ofSVT
Alternatives:
•atenolol2,5 mg iv. at 1 mg/min repeated
at 5 minutesintervalsto a maximumdose
of10 mg
•sotalol20-60 mg iv. over10 minutesin
patientswithestimatedglomerular
filtrationrate more than60
•DC cardioversion

12. Atrialtachycardia

13. Multifocalatrialtachycardia
•Most commonlyoccursinCOPD.
•Thereare at least3 morphologically
distinctPwaveswithirregularP-P
intervals.
•Itis veryimportantto correcthypoxia
andhypercapnia.
•Ifheartrate >110 bpm, verapamilor a
BB canbeusedas well.

14. Imagesource: lifeinthefastlane.com
Thereare at least3
morphologicallydistinctP
waveswithirregularP-P
intervals.

15. Junctionaltachycardia
AV nodal re-entry tachycardia (AVNRT)
AV re-entry tachycardia (AVRT)
Hisbundletachycardia

16. Junctionaltachycardia
•Vagalmanoeuvresincasesof
anterogradeconductionthrough
theAV node.
•Adenosine!
•Beta blockersor amiodarone!
•Radiofrequencyablation!

17. Wolff-Parkinson-White
syndrome(WPW)
•Itis causedbycongenitalaccessory
conductionpathwaybetweenatria
andventricles.
•ECG: shortPR interval, wideQRS
complexdueto slurredupstroke
(delta wave) andST-T changes.

18. Wolff-Parkinson-White
syndrome(WPW)
•WPW typeA: positivedelta waveinV1.
•WPW typeB: negative delta waveinV1.
Delta wave

19. Wolff-Parkinson-White
syndrome(WPW)
•PatientsmaypresentwithSVT.
•Tachycardiamaybedueto an
AVRT, pre-excitedatrial
fibrillationor flutter.
•Electrophysiologicaltestingand
ablationofaccessorypathway!

20. LongGanongLevinesyndrome
Itis similarto WPW
syndrome, except
thereis no delta
waves!

21. Holidayheartsyndrome
•Bingedrinkingina personwithout
anyclinicalevidenceofheartdisease
mayresultinacutecardiacrhythm
andconductiondisturbances.
•Recreationaluse ofmarijuanamay
havesimilareffects.

22. Holidayheartsyndrome

23. Stop heavy
drinking!

24. Literature
•OxfordHandbookofClinicalMedicine.
LongmoreM. WilkinsonI. B. Baldwin A.
ElizabethW. Ninthedition.
•Lifeinthefastlane.com
•Ecgcore.com