Study to Evaluate the Safety of Twice Daily Oral Carvedilol

Inclusion Criteria: * Male or female patients with chronic symptomatic congestive heart failure (CHF) due to systemic ventricular systolic dysfunction, who are receiving standard heart failure therapy and have successfully completed the maintenance phase of the Pediatric Carvedilol Study 321. * Parent or guardian of patient able and willing to give written informed consent. The written assent from children \> 9 years of age is also required. Exclusion Criteria: * A patient who, in the opinion of the investigator, would not benefit from open-label carvedilol. * A patient who, in the opinion of the investigator, is incapable of cooperating with the requirements of this study. * A patient treated with the following medications at the time of entry in the study: * Monoamine oxidase (MAO) inhibitors; * Calcium entry blockers; * α- blockers, or labetalol; * Disopyramide, flecainide, encainide, moricizine, propafenone; * Intravenous inotropes such as dobutamine or intravenous vasodilator agents such as amrinone or milrinone; * Intravenous CHF medications (e.g. diuretics, digoxin); * Beta-blockers, other than double-blind carvedilol. * Uncorrected primary obstructive or severe regurgitative valvular disease, nondilated (restrictive) or hypertrophic cardiomyopathy, or significant systemic ventricular outflow obstruction. * A patient with any of the following contra-indications to beta-blocker therapy: * Heart rate \< 2nd percentile for age; * Unacceptable blood …