Presentation on theme: "Acute Management of Stable Narrow Complex Tachycardia"— Presentation transcript:
1 Acute Management of Stable Narrow Complex Tachycardia Mini Lecture2013
2 ObjectivesReview the initial approach to diagnose and treat narrow complex tachycardiaReview examples of AVNRT, AVRT, Atrial TachycardiaThis is not a comprehensive review of all the narrow complex tachycardiasYou are not expected to manage these patients on your own, always ask for back up
3 CaseNurse calls to inform you that bed 10’s heart rate just went up to 200s on telemetry. Which of the following information should you obtain asap?A. Blood pressureB. Mental statusC. EKGD. Focused Physical ExamE. All of the aboveAnswer E intern should ask the nurse these questions on the phone so the nurse can start getting the information that you need if he or she doesn’t have it already. Then go see the patient asap.
4 CaseNurse calls to inform you that bed 10’s heart rate just went up to 200s on telemetry. Which of the following information should you obtain asap?A. Blood pressureB. Mental statusC. EKGD. Focused Physical ExamE. All of the aboveAnswer E,
5 Narrow Complex Tachycardia Rate >100 (often )QRS <120 msecRegularSinus tachycardia (usually <150)AVNRTAVRTAtrial TachycardiaAtrial Flutter with regular block (150, 100, 75)IrregularAtrial FibrillationMATBe aware of they types of narrow complex tachycardia or “SVT”We will only talk more about AVNRT, AVRT, ATRIAL TACHYCARDIA in more detail
6 Initial Assessment for Tachycardia QuestionsSymptomatic?Hypotensive?12 lead EKGIV accessStable or Unstable?Altered Mental StatusHypotensionChest PainAcute SOBHypoxiaBack to the initial assessment when you are called by the nurse- it is Important to first decide if this is an unstable or stable situation
8 Stable? Initial Assessment Focused H&PTalk to the patient to assess mental statusReason for admission (sepsis, ACS)Cardiac Hx (CAD, HF, Afib, SVT)Recent electrolytesMedications (AV nodal agents, digoxin)Listen to heart and lungsVolume statusJVDRun through the following in your evaluation4H’s: Hypovolemia, Hypoxia, Hyperthermia, Hyper/Hypokalemia,4T’s: Tamponade, Tension PTX, Thromboembolism, Toxins,
10 Too fast to interpret rhythm? Vagal Maneuvers and AdenosineSlow down the rhythmTerminate certain SVTs which conduct through the AV nodeIf possible obtain 12 lead EKG recording during intervention
11 Vagal maneuvers Adenosine Bearing down Face in ice cold water Carotid MassageBlowing into a folded strawCoughAdenosineMay avoid if bronchospasm/asthma/COPD?Caution if history of pre-exitation/ WPW?*Warn them about the symptoms6mg IV push followed by NS flush followed by12mg IV push followed by NS flushSensation that the heart has stopped, chest pain, shortness of breathCrash Cart Should Be available in the event that the patient becomes unstable i.e. you may need atropine for a long pause or urgent cardioversionDon’t forget to obtain frequent vital signs while you are at the bedsideTachyarrythmias and WPW- AV nodal blocking agents are contraindicated
12 AVNRT Cause DX Rate 150-250 Inverted p or “psuedo S” Tx Vagal Dual AV nodal pathways with differing refractory periodsOften initiated by a PAC60% SVTDXRateInverted p or “psuedo S”TxVagalAdenosineBB: Metoprolol 5mg q5min x3CCB: Diltiazem 10mg IV, repeat 10-30mg IV in 5-10 minSince it is a nodal rhythm, adenosine/vagal/BB.CCB can terminate the rhythm
13 AVNRTPSUEDO S WAVESV4 p wave at the end QRS, and characteristic “pseudo S wave”
14 AVRT Cause Dx: Rate 150-250 Retrograde P inferior leads Tx: Vagal AdenosineBB: Metoprolol 5mg min q5 x 3CCB: Diltiazem 10mg IV, repeat 10-30mg IV in 5-10 minCauseRe-entrant tachycardic circuit with conduction down AV node and back up a bypass tract (i.e. WPW)30% SVTWPW is an example of AVRT, use caution with AV nodal agents which can stimulate the bypass tract causing degeneration to vfib because AV nodal blocking agents can speed up the bypass tract (you can try to look at an ekg taken prior to event to look for pre-exitation, you should discuss with cardioology fellow)
15 AVRT Narrow complex rate ~ 150 Retrograde p waves seen in ST segment (unlike AVNRT where p is usually burried)
16 Atrial Tachycardia Cause Dx P wave precedes each QRS Enhanced Automaticity of atrial tissue or ectopic atrial pacemaker10% SVTDxP wave precedes each QRSUnusual p wave axisAdenosine may show continued atrial beats, without AV conductionTx:BB: metoprolol 5mg q5 x 3CCB: Diltiazem 10mg IV, repeat 10-30mg IV in 5-10 minAdenosine will not terminate this rhythm, but it can help with the dx
17 Atrial Tachycardia ADENOSINE Unusual p wave axis Continued atrial automaticityInitally you can see tachycardia with unusual p wave axisThis is a rhythm strip with adenosine administration showing continued atrial beats when AV node is blocked indicating atrial tachycardia rather than AVNRT, AVRTThis is a MKSAP question
18 General PrinciplesNote the common theme: Vagal Maneuvers, Adenosine, Beta Blockers, Calcium Channel Blockers, caution in WPWCheck vitals (BP) frequently during acute setting to make sure a stable situation does not become unstableAgain, this is meant to be a review of the initial management of SVT you are not expected to independently manage these patients- Call for backup!
19 Case Follow UpNurse calls: “ Bed 10’s heart rate just went up to 200s”You reply:What is his blood pressure?Is his arousable and oriented?Please get a 12 lead EKG nowDoes he have IV access?I’ll be right there..
20 References UpToDate Med Res UCLA http://medres.med.ucla.edu/ FP NotebookImages sited previously