We are truly saddened to hear about your family friend's condition and we are here to support you in prayer and in offering biblical encouragement.
Firstly, it's important to remember that God is our ultimate healer. As it is written in Psalm 103:2-3, "Bless Yahweh, my soul, and don’t forget all his benefits; who forgives all your sins; who heals all your diseases." We can trust in God's power to heal and restore. This is not the healing of some magical potion or even of doctors, but from God Himself.
In times of sickness, we are also encouraged to call upon the elders of the church for prayer. James 5:14-15 says, "Is any among you sick? Let him call for the elders of the assembly, and let them pray over him, anointing him with oil in the name of the Lord, and the prayer of faith will heal him who is sick, and the Lord will raise him up. If he has committed sins, he will be forgiven." Again, please do not neglect going to the doctors, but also call upon those spiritually mature in the faith.
Let us pray together:
"Father in heaven, we come before You in the name of Jesus Christ, seeking Your healing power for our family friend who is currently suffering from cardiac failure. We ask that You guide the hands of the medical professionals, Lord, and that Your healing power would flow through this situation. Remember he ultimately needs you as his healer, not just medical doctors. Remember that healing is from you and not the skills of man or some magical potions. We also pray for his spiritual health, Lord, that You would draw him closer to You during this time. If he does not know Jesus as his personal savior, then reveal yourself to him and convict him of his sins. We pray that he will be forgiven and raised up, Lord, and that Your will be done in his life. Encourage him to call upon You directly and in faith. In Jesus' name, we pray. Amen."
Remember, it is also by His wounds that we are healed. Isaiah 53:5 says, "But he was pierced for our transgressions. He was crushed for our iniquities. The punishment that brought our peace was on him; and by his wounds we are healed." God allowed Jesus to be hurt, so that by His wounds we could be healed. This is not just talking about spiritual wounds, but also physical wounds.
Lastly, we want to encourage you to continue trusting in God's goodness, even in this difficult time. Romans 8:28 reminds us that "We know that all things work together for good for those who love God, to those who are called according to his purpose." God has the ability to bring blessings from even the most difficult of circumstances. Our belief in Jesus Christ is what is required for us to have access to God. The Bible clearly tells us that if we believe in the Lord Jesus Christ, we will be saved. This means we are saved from our sins and can be in God's presence when we die. Acts 4:12 says about Jesus, "There is salvation in none other, for neither is there any other name under heaven, that is given among men, by which we must be saved!" This is because Jesus died on the cross and took the punishment for the sins of the world upon Himself. But this does not automatically save us. We must believe in Him and His sacrifice to be saved. This involves repenting (turning away) from our sins and trusting in Jesus as our savior.