Transcript Efficacy of Vagal Maneuvers in the Treatment of PSVT

Efficacy of Valsalva Maneuvers
Versus Drug Therapy in the
Treatment of PSVT
Beth Froelke
MSIII
Outline
• Patient Presentation
• Supraventricular Tachycardia
– What is it?
– Treatment Options
• Utility of vagal maneuvers in ED setting
– Underused
– Improper technique
Patient Presentation
• Z.S.
– 48 year old Female
– PMH:
• Remote h/o SVT: “years” prior converted to NSR with drug;
uncertain whether she had an echocardiogram in past; has
had a couple brief instances of heart fluttering this year
• Asthma; Hypothyroidism
– Palpitations:
• Performed Valsalva as instructed by cardiologist seen at
OSH but did not stop palpitations
• Has no PMD; no current cardiologist
• We did not ask how vagal maneuvers were performed
– No other presenting complaints
• Family History: non-contributory
• Social History: non-smoker, no ETOH
• ROS: negative (denies chest pain, SOB;
lightheadedness)
• Meds: none
• Allergies: NKDA
• PE:
– BP 135/80; Pulse 190; RR 18; O2sat 98%RA
– Anxious
– Tachycardia
Pretreatment ECG
Paroxysmal Supraventricular
Tachycardia
Causes:
– *Reentrant circuit at AV node (AVNRT)
• Fast pathway with slow refractory and slow pathway with fast
refractory period
• Normal hearts; MI, pericarditis, valve disease
• EKG: “pseudo” S wave II, III, aVF (retrograde P); short RP
• Treatment options
– Unstable: Cardioversion – 50 J
– Stable
• Vagal maneuvers
• Adenosine, verapamil, Beta-blockers
• Z.S. after receiving adenosine 6mg IV…
Post-treatment ECG
Z.S.
• BP 117/66; HR 96; RR 18; O2sat 100%RA
• Monitored
– Labs: Cardiac enzymes (normal); BMP, CBC
– Toprol XL 50mg po X 1
• Discharged to home
– Toprol XL 50mg po qday
– Instructions: see PMD for referral to
cardiologist and EP study
Vagal Maneuvers
• Recommended first line for stable patients
– Valsalva, carotid massage
– Appropriate techniques
• CM: Check for pulses and bruits bilaterally; 10 sec
steady pressure on carotid of NDH
• Valsalva: (Wong et al., 2004)
– Expire against a closed epiglottis for 15 seconds
– Pathophysiology
What do we do in the ED?
• Vagal maneuvers becoming more and more
neglected as first line intervention than drug
therapy
• Efficacy of drug versus vagal maneuvers
– Adenosine/verapamil more successful than vagal
maneuvers
• Taylor et al. (1999): retrospective
–
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Valsalva: 1st line intervention 36.7%; success: 6.1%
Adenosine: 1st line intervention 32.7%; success: 68%
Sinus Massage: 1st line 26.5%; success 2%
Verapamil: 1st line 4.1%; Success 14%
• Others studies have shown similar rates of success
between verapamil and adenosine (DiMarco et al., 1990)
• Possible causes of failed conversion to
NSR with Valsalva
– Varied positions have varied results
• Wong et al., 2004
– 65 healthy subjects; single blind; repeated-measures
– 5 Valsalva positions: supine; supine with epigastric
pressure; supine with legs raised, semi-recumbent,
sitting
– EKG: R-R interval changes with each maneuver
– Results: supine and supine with epigastric >> supine with
legs raised, semi-recumbent, sitting
• Majority of studies assessing efficacy of Valsalva
do not describe how it is performed
• Varied instruction by physicians
– Taylor and Wong, 2004
• Small scale study (N=17 physicians): asked to
describe how they would instruct a patient to
perform VM in the case of SVT
• 9.6% correctly described how to position patient
• Most would place patient in sitting or semirecumbent position
• Cost benefit
– Side effects of drugs
• Adenosine: flushing, chest pain/pressure, dizziness; serious
reactions: asystole, arrhythmias
– Side effects of vagal maneuvers
• Valsalva: few side effects (transient lightheadedness)
• Carotid massage: stroke, not generally recommended in
older age, CVA risk patients
– $$$:
• Vagal maneuvers - FREE
– Efficacy
• Adenosine or Verapamil > Valsalva or CM