PVC`s in the Office Setting: What Do You Do?

PVC’s in the Office Setting: What Do You Do?
Michael H. Kim, MD
Director, Arrhythmia Service
Director, Electrophysiology Fellowship Program
Warren Alpert Medical School of Brown University
Providence, RI
9/26/12
What are PVC’s?
• Premature beat originating in the V characterized on surface ECG by wide QRS (generally > 120 msec) and altered QRS morphology independent of atrial activation.
• May be due to enhanced automaticity, triggered activity, or re‐entry. • Most are followed by a compensatory pause as it fails to conduct to the atria and does not usually reset the SA node; if the PVC is interpolated, cannot tell by pulse check/exam.
• Definitions: Isolated or simple PVC, couplet, NSVT (3 or more at rate > 120); multiform/R on T/couplets and NSVT are termed “complex.”
• COMMON and frequent reason for office visits.
Ventricular Ectopy with Advancing Age
• Effect of age on probability 60%
(%) of
having more than a
50%
given number of
40%
PVCs per 24 hours
in subjects with
30%
normal hearts.
> 0 PVCs
> 50 PVCs
> 100 PVCs
20%
10%
0%
10-29 30-39 40-49 50-59 60-69
Data from Kostis JB. Circulation.
1981;63(6):1353.
Age
Kastor, JA. Arrhythmias. 1994.
Incidence in Specific Populations
• Post‐MI: 30 % have >/‐ 3 PVC/hr; 20 % more than 10/hr. Stabilizes after about 3 months.
• NICM (dilated cardiomyopathy): 80 to 100 % have PVC’s; 42 % frequent (more than 1,000/24 hrs); 78 % couplets; 42 to 49 % NSVT on holter.
• HCM: 83 % with PVC; 60 % complex PVC; 19 % NSVT; 28 % with more than 100/24 hrs.
• Hypertension: increased rate with LVH on ECG or echo; increased rate of NSVT with LVH. 2 % in controls; 10 % HTN; 32 % in HTN with LVH for 10+ PVC/hr over 48 hours.
High‐Risk Subgroups Who Need Further Evaluation
• Survivors of sudden death
• Post‐MI, reduced EF (and ventricular ectopy if EF >30% to 40 %).
• Recurrent unexplained syncope
• Idiopathic cardiomyopathy with syncope or VT
• Hypertrophic cardiomyopathy with syncope or VT
• Right ventricular dysplasia/Brugada
• Long QT syndrome
CAST‐I
Prognosis of Post-MI Patients Treated with Placebo vs. Encainide/Flecainide
Patients Without Event (%)
100
95
Placebo (n = 743)
P = 0.001
90
Encainide or
Flecainide (n = 755)
85
80
0
91
182
273
364
Days After Randomization
Echt DS. N. Engl J Med. 1991;324:781-788.
455
How to Evaluate PVC’s
•
•
•
•
History (symptoms/FH); stimulants, exposures.
Exam/assessment for SHD (echo).
PVC burden assessment (holter).
12 lead ECG. Capture the PVC in all leads!
• Other testing depends on results of the above.
Pts with No SHD
• In general, isolated PVC’s even when relatively frequent do not cause significant hemodynamic effects.
• Isolated PVC’s in pts who are healthy without SHD are “benign.” Prognosis is excellent. Remove aggravating factors (caffeine, nicotine, sympathomimetics). Treatment is for symptoms if significant (first line is beta‐blockers, then CCB).
• Rare exceptions do exist for adverse outcomes related to PVC’s in pts without apparent SHD: single or repetitive PVC’s originating from the His‐Purkinje network or RVOT initiating VF (selected pts with Brugada or LQTS).
• No evidence that treating PVC’s (suppression) improves mortality so the focus is on symptoms.
No SHD Counterpoint
• Some pts may have troubling symptoms: usually palpitations. Also pounding neck sensation; reduced stroke volume—
fatigue, exertional symptoms, dyspnea. Chest pain.
• Although felt to be “benign:” frequent PVC’s can result in LV dilatation and cardiomyopathy (potentially reversible). PVC Induced Cardiomyopathy
• Tachycardia induced cardiomyopathy has been noted for VT and other arrhythmias due to rapid VR.
• Exists for RVOT VT (2 main types: non‐sustained, repetitive, mono VT; paroxysmal, exercise‐induced, sustained VT). Both have typical LB, inferior axis, adenosine sensitive. Cellular mechanism is cAMP‐mediated triggered activity dependent on delayed afterdepolarizations.
– Subtype is repetitive, monomorphic PVC.
Bhushan M, Asirvatham SJ. Current Heart Failure Reports 2009; 6: 7‐13.
PVC Burden and LV Function
• Critical burden of PVC associated with cardiomyopathy assessed: Baman TS, et al. Heart Rhythm 2010; 7: 865‐869.
• Consecutive group of 174 pts referred for idiopathic PVC ablation. RVOT (n=65) and epicardium (n=22) most common sites.
• Holter/Echo data.
• 1/3 of pts had cardiomyopathy.
• The lowest PVC burden with reversible cardiomyopathy was 10 %.
• **A PVC burden of > 24 % was independently associated with cardiomyopathy.
Clinical Implications
• High PVC burden >/‐ 24 %: treatment reasonable even if no symptoms. Ablation vs Drugs.
• PVC burden < 24 %. Check echo to assess LVEF/cardiac dimensions. ? Annual or timing of repeat imaging.
• Cardiomyopathy and PVC burden > 10 %: Treatment?
• Threshold PVC burden: 10 %?
Outflow Tract PVC/Tachycardia
• RVOT more in females; LVOT more in males.
• Typical presentation is with salvos of ventricular ectopic beats
or NSVT; sustained VT not uncommon.
• Palpitations, presyncope, lightheadedness. Frank syncope uncommon (< 10 %). Rare fatality (only one case report in no SHD) outside of selected pts.
• In women, occur more often in pre‐menstrual and peri‐
menopausal periods and during pregnancy.
• Triggers: exercise (both acceleration and recovery), stress, anxiety, stimulants.
49 yo woman with 4 yr hx of cardiomyopathy, EF 35 % referred for ICD. Hx of frequent PVC’s (30 % burden)
Post‐ablation of RVOT PVC’s
• EF improved to 49 % at 2 months. No ICD. Fatigue and DOE gone. PVC burden < 1 %. One year later, EF 53 %; holter showed 2 PVC’s.
• Pre‐ablation cath and MRI showed no CAD, no ARVD or scar.
35 yo male with palpitations and tachycardia
6 months later still with palpitations and no tachycardia
6 months post‐ablation of Left PS AP: Holter
Post‐ablation of idiopathic LV PVC
PVC Morphology in the Office: Pilot with Palpitations, worse with exercise
ETT: Peak Exercise/Recovery
Pace Map: AS below the PV
Idiopathic: PVC or VT • In general, anatomic right high and left low are reasonable first line options for symptomatic PVC’s or VT in pts with no SHD.
• Right High = RVOT (Left bundle, inferior axis)
• Left Low = Idiopathic LV/fascicular VT (Right bundle, superior axis)
• High rate of successful ablation (80 to 90 %) with low risk of complications.
• Often exercise or catecholamine induced.
• Other areas have generally lower success rates and higher risks (LVOT for example/coronary artery risk, higher pacer risk).
• Estimated about 10 to 20 % of VT cases in US referral centers are Idiopathic.
Question: At what threshold PVC burden should there be a trigger for further evaluation for SHD in an otherwise asymptomatic, healthy individual?
•
•
•
•
A) 10 %
B) 24 %
C) 1 %
D) A few (< 1 %)