This study compares two medicines, **carvedilol** and **metoprolol succinate**, for heart failure patients with an **implantable cardioverter defibrillator (ICD)**. Heart failure with reduced ejection fraction (HFrEF) means the heart doesn't pump well. An ICD is a small device that helps control heartbeats and prevent sudden cardiac death. The study aims to enroll 2,000 patients across the U.S. Participants will be on the study for up to 3 years and will switch from metoprolol succinate to carvedilol or continue their current treatment. Doctors will check on them regularly to see how well the ICD works and monitor their health.

• The study lasts about 3 years with regular visits.
• Participants must currently take metoprolol succinate and be willing to switch medications.
• Eligible participants must have reduced heart function and an ICD.

For more details, visit the study's website: www.carvtop.org