In the National Heart, Lung and Blood Institute's Cardiac Arrhythmia Suppression Trial (CAST), a long-term, multi-center, randomized, double-blind study in patients with asymptomatic non-life-threatening ventricular arrhythmias who had had a myocardial infarction more than 6 days but less than 2 years previously, an excessive mortality or non-fatal cardiac arrest rate (7.7%) was seen in patients treated with encainide or flecainide compared with that seen in patients assigned to carefully matched placebo-treated groups (3.0%). The average duration of treatment with encainide or flecainide in this study was 10 months.
The applicability of the CAST results to other populations (e.g., those without recent myocardial infarction) is uncertain. Considering the known proarrhythmic properties of Norpace or Norpace CR and the lack of evidence of improved survival for any antiarrhythmic drug in patients without life-threatening arrhythmias, the use of Norpace or Norpace CR as well as other antiarrhythmic agents should be reserved for patients with life-threatening ventricular arrhythmias.
Norpace disopyramide phosphate capsules Norpace CR disopyramide phosphate extended-release capsules
Norpace (disopyramide phosphate) is an antiarrhythmic drug available for oral administration in immediate-release and controlled-release capsules containing 100 mg or 150 mg of disopyramide base, present as the phosphate. The base content of the phosphate salt is 77.6%.
Norpace and Norpace CR are indicated for the treatment of documented ventricular arrhythmias, such as sustained ventricular tachycardia, that, in the judgment of the physician, are life-threatening. Because of the proarrhythmic effects of Norpace and Norpace CR, their use with lesser arrhythmias is generally not recommended. Treatment of patients with asymptomatic ventricular premature contractions should be avoided.
Initiation of Norpace or Norpace CR treatment, as with other antiarrhythmic agents used to treat life-threatening arrhythmias, should be carried out in the hospital. Norpace CR should not be used initially if rapid establishment of disopyramide plasma levels is desired.
Antiarrhythmic drugs have not been shown to enhance survival in patients with ventricular arrhythmias.
Published Studies Related to Norpace (Disopyramide)
Prospective comparative study of intravenous cibenzoline and disopyramide therapy in the treatment of paroxysmal atrial fibrillation after cardiovascular surgery. [2010.09]
CONCLUSIONS: The efficacy of iv cibenzoline for the termination of postoperative paroxysmal AF was significantly better than that of disopyramide, especially in patients with pre-administration of oral beta-adrenergic blockers and those with smaller left atrium.
Comparison of acute reduction in left ventricular outflow tract pressure gradient in obstructive hypertrophic cardiomyopathy by disopyramide versus pilsicainide versus cibenzoline. [2010.11.01]
Negative inotropic agents are often administered to decrease the left ventricular (LV) pressure gradient in patients with obstructive hypertrophic cardiomyopathy (HC)... Accordingly, sodium channel blockade might be more important for reducing the LV pressure gradient at rest in patients with obstructive HC than calcium channel blockade or beta blockade.
High efficacy of disopyramide in the management of ventricular fibrillation storms in a patient with Brugada syndrome. [2010.06.01]
The patient was a 57-year-old man with Brugada syndrome, who had been implanted with a implantable cardioverter defibrillator (ICD). The frequency of ventricular fibrillation (VF) started to increase about 4 years after ICD implantation, occurring, at worst, six times in one night.Findings observed in our case suggest that disopyramide could be added in our arsenal of medications for treating arrhythmic storms in patient with Brugada syndrome.
Torsades de Pointes induced by a combination of garenoxacin and disopyramide and other cytochrome P450, family 3, subfamily A polypeptide-4-influencing drugs during hypokalemia due to licorice. [2010.04]
We report an 82-year-old man who developed ventricular tachycardia and Torsades de Pointes (TdP) after oral administration of garenoxacin, a novel quinolone antibiotic agent that differs from the third-generation quinolones, for pneumonia... Therefore, although garenoxacin reportedly causes fewer adverse reactions for cardiac rhythms than third-generation quinolone antibiotics, one must be cautious of the interference of other drugs during hypokalemia in order to prevent TdP.
Possible acute and chronic synergistic effect of dual chamber pacing and disopyramide in obstructive hypertrophic cardiomyopathy: a case report. [2010.01]
It remains unclear whether the combination of dual-chamber (DDD) pacing and disopyramide can achieve prolonged left ventricular outflow tract (LVOT) gradient reduction and symptom relief in patients with obstructive hypertrophic cardiomyopathy (HCM)... This combination might enable physicians to treat and manage elderly symptomatic obstructive HCM patients with a severe LVOT gradient more effectively and less invasively.
Clinical Trials Related to Norpace (Disopyramide)
Catheter Ablation Compared With Pharmacological Therapy for Atrial Fibrillation (CAPTAF Trial) [Active, not recruiting]
The objective is to compare the efficacy of 2 treatment strategies, catheter ablation of
atrial fibrillation versus optimized pharmacological therapy, in patients with symptomatic
It is a randomized, prospective, controlled, open-label multicentre, parallel-group study
including 116 patients. Inclusion criteria are patients aged 30-70 years with symptoms
related to atrial fibrillation and who have failed or been intolerant to at least one
anti-arrhythmic drug, with at least one atrial fibrillation episode documented on ECG during
the previous 12 months and at least one symptomatic episode during the previous 2 months or
at least 2 symptomatic episodes of persistent AF in the previous 12 months.
Main exclusion criteria are patients who have tested 2 or more anti-arrhythmic drugs for
rhythm control, uncontrolled hypertension, valvular disease requiring anticoagulation,
planned valve surgery within 2 years, contraindication to treatment with anticoagulants,
heart failure, left atrial diameter > 60 mm, unstable angina or acute myocardial infarction
within the last 3 months, cardiac revascularization procedure within the last 6 months,
prior cardiac surgery or planned cardiac corrective surgery within 1 year, prior AF ablation
The primary endpoint is general health-related quality of life at 12 months follow-up. The
main secondary endpoints are morbidity and mortality as composite outcome, cardiovascular
hospitalization, symptoms, heart failure, left atrial and ventricular function and
diameters, exercise capacity, health care economics, rhythm, atrial fibrillation burden,
successful versus failed treatment, safety and "cross-overs" over time.
Patients will receive a cardiac monitor, implanted subcutaneously, which will monitor the
heart rhythm during a two month "Run-in" period, for the definition of the basic atrial
fibrillation burden. Patients will be randomly assigned to an antiarrhythmic drug (for
rhythm or rate control) or to left atrial catheter ablation. Evaluation of outcome is at 12,
24, 36 and 48 months of follow-up, while health economy will be evaluated at 24 and 48
months of follow-up.. In case of documented disease progression or unacceptable toxicity,
subjects will be switched to the alternative regimen. The main statistical analysis of the
primary endpoint will be based on the intention-to-treat population. The trial duration is
AV Node Ablation and Pacemaker Therapy Compared to Drug Therapy for Atrial Fibrillation - Pilot Study [Terminated]
The purpose of this study is to determine whether early atrioventricular node (AVN) ablation
with pacing device therapy will reduce death and hospitalization when compared to the
conventional drug therapy in elderly patients with recurrent and symptomatic atrial
Atrial Fibrillation Follow-up Investigation of Rhythm Management (AFFIRM) [Completed]
To compare two standard treatment strategies for atrial fibrillation: ventricular rate
control and anticoagulation vs. rhythm control and anticoagulation.
Reports of Suspected Norpace (Disopyramide) Side Effects
Femur Fracture (6),
DRY Mouth (6),
Blood Cholesterol Increased (6),
HIP Fracture (6),
Myocardial Infarction (3),
Thoracic Vertebral Fracture (3), more >>
Page last updated: 2011-12-09