Ventricular Arrhythmias:A General Cardiologist’s Assessment of Therapies in 2004
C.Richard Conti M.D. MACC
Evaluation of PVCs
Start with the History and physical examination.
Documentation of the arrhythmia is critical.
ECG.
Holter monitor.
Event monitor.
Reveal monitor.
Management
Management of PVCs differs in patients with and without structural heart disease.
To define structural heart disease, consider:
Echocardiography.
ETT.
Left heart catheterization.
PVCs in the Absence of Structural Heart Disease
In the absence of structural heart disease, ventricular ectopy is generally benign, carrying no prognostic significance.
Treatment with antiarrhythmic therapy is not indicated unless the patient is unacceptably symptomatic.
PVCs in the Absence of Structural Heart Disease
Treatment
Reassurance.
Avoidance of stimulants.
Caffeine.
Cigarettes.
Beta blockers.
Antiarrhythmic drugs as a last resort.
PVCs in the Absence of Structural Heart Disease
If antiarrhythmic drugs are necessary:
Class 1C:
Flecainide.
Propafenone.
Mexilitene.
Amiodarone is rarely, if ever, indicated.
Management of Ventricular Ectopy in the Presence of Structural Heart Disease
AVID
Antiarrhythmics Versus Implantable Defibrillators
Sponsored by: – National Institutes of Health
Entry Criteria: – VF – VT with syncope – VT without syncope, with EF < .40, and SBP < 80mm Hg, chest pain, CHF, or near syncope
Treatment: – ICD vs. empiric amiodarone or Holter/EP-guided sotalol
Primary endpoint: – Total mortality
AVID Investigators. N Engl J Med. 1997;337(22):1576-1583.
Survival in AVID Patients
Adapted from: Domanski MJ, et al. J Am Coll Cardiol 1999; 34:1090-1095.
LVEF <0.20 (Group 1)
LVEF 0.20 - 0.34 (Group 2)
LVEF > 0.34 (Group 3)
1.0
.9
.8
.7
.6
.4
.3
.2
.1
0
.5
Cumulative Survival
0
12
24
Device
Drug
1.0
.9
.8
.7
.6
.4
.3
.2
.1
0
.5
Cumulative Survival
0
12
24
Device
Drug
ICD Therapy for Sustained Ventricular Arrhythmias: Secondary Prevention
Conclusions
The results of AVID support using the ICD as front-line therapy to prolong total and sudden death survival in patients at high risk for sudden death e.g.Poor LV function.
This trial included patients with both ischemic and nonischemic substrates.
ICD Therapy
Primary Prevention
ICM
MADIT
Multicenter Automatic Defibrillator Implantation Trial
Hypothesis: ICD will reduce mortality (all-cause) in high-risk CAD patients.
Moss AJ. N Engl J Med. 1996;335:1933-1940.
MADIT Inclusion Criteria
Prior Q-wave MI
Nonsustained VT
EF < 35%
Inducible, non-suppressible VT
NYHA Class I – III
Age 25 - 80
> 3 weeks from last MI
No requirement for revascularization
Moss AJ. N Engl J Med. 1996;335:1933-1940.
MADIT Patient Flow
Non-inducible (n = 139)
Patients meeting inclusion criteria (N = 483)
EP study
Suppressible with IV procainamide (n = 91)
Refused study (n = 57)
Inducible (n = 344)
Non-suppressible (n = 253)
Signed consent form, randomized (n = 196)
MADIT FDA Info Pack. May 16, 1996.
MADIT Survival
Moss AJ. N Engl J Med. 1996;335:1933-1940.
1.0
0.8
0.6
0.4
0.2
0.0
0
1
2
3
4
5
Year
Probability of survival
Conventional
therapy
Defibrillator
MADIT Conclusion
In patients with a prior MI who are at a high risk for ventricular tachyarrhythmia, prophylactic therapy with an implanted defibrillator leads to improved survival as compared with conventional medical therapy.
Moss AJ. N Engl J Med. 1996;335:1933-1940.
MUSTT Multicenter UnSustained Tachycardia Trial
Sponsors:
NHLBI and Industry
Buxton AE. N Engl J Med. 1999;341:1882-90.
MUSTT Hypothesis
Antiarrhythmic (AA) therapy guided by EP testing can reduce the risk of arrhythmic death and cardiac arrest in patients with:
CAD
EF < 0.40
Asymptomatic nonsustained VT ( > 3 beats, < 30 sec, rate > 100 bpm)
Buxton AE. N Engl J Med. 1999;341:1882-90.
MUSTT Endpoints
Primary:
Arrhythmic death or cardiac arrest
Secondary:
Total mortality
Cardiac mortality
Spontaneous, sustained VT
Buxton AE. N Engl J Med. 1999;341:1882-90.
MUSTT Initial Protocol
EPS N=2202
Evaluate and Treat Ischemia
No Sustained VT Induced
N=1435 (65%)
Inducible Sustained VT
N=767 (35%)
Registry
Randomized N=704 (92%)
Refused Randomization N=63 (8%)
CAD, NSVT, EF < 0.40
Buxton AE. N Engl J Med. 1999;341:1882-90.
MUSTT Protocol Randomized Treatment Groups
Inducible Sustained VT N=704
No EP-Guided Rx
ACE I & ?B N=353
EP-Guided Rx
ACE I & ?B N=351
Buxton AE. N Engl J Med. 1999;341:1882-90.
MUSTT Conclusions
For CAD patients with EF < .40, asymptomatic NSVT and inducible VT:
ICD therapy significantly reduces the incidence of:
Arrhythmic death or cardiac arrest (73% – 76% reduction)
Total mortality (55% – 60% reduction)
EP-guided pharmacologic antiarrhythmic therapy provides no survival benefit
Buxton AE. N Engl J Med. 1999;341:1882-90.
Nonischemic Cardiomyopathy and NSVT
DEFIbrillators in Non ICM Treatment Evaluation (DEFINITE).
Multicenter randomized trial.
Non Ischemic Cardiomyopathy
LVEF < 35%.
Symptomatic heart failure.
DEFINITE
Spontaneous arrhythmia (>10 PVCs/hr or 3 beats NSVT.
Randomized ICD vs. no ICD.
Standard heart failure medications.
Primary endpoint mortality.
Image ?(Heart Failure/Transplant)
DEFINITE Trial 39 KB???File Type: GIF Click here to enlarge / download for presentation use (ie. PowerPoint)
DEFINITE
Overall Conclusions
Asymptomatic patients with ventricular arrhythmias and no underlying heart disease do not need to be treated.
Symptomatic patients with arrhythmias should be treated with standard therapy and ICD. Management depends on the frequency and severity of the patient’s arrhythmia.
Conclusions
The results of AVID support using the ICD as first-line therapy to prolong total and/or sudden death survival in patients with documented unstable VT or VF.
Conclusions
MUSTT is concordant with MADIT, suggesting that risk stratification using invasive techniques should be the standard of care for post-infarction patients who have NSVT and significant LV dysfunction.
Conclusions
The patient with NICM and NSVT is difficult to risk stratify. If syncope has occurred, there is some data to support implantation of an ICD.
In the asymptomatic patient, the answer is not clear at this time.