**SELUTION 4 De Novo Small Vessel IDE Trial** This study is testing the safety and effectiveness of a new treatment called SELUTION SLR 014 PTCA DEB for small heart arteries. These arteries are 2.00 mm to 2.75 mm wide. The study aims to enroll 910 people at many locations worldwide, with at least half in the US. Participants will either receive the SELUTION treatment or a standard treatment called DES. DES stands for Drug-Eluting Stent, a device placed in arteries to keep them open. Participants have certain conditions like chronic coronary syndrome, unstable angina, or a specific type of heart attack. They must be 18 or older, not pregnant, and able to take certain heart medications. Some may join extra studies involving imaging or blood tests. **Key Points:** - The study includes treatments like SELUTION DEB or DES for heart arteries. - Participants must follow specific rules and attend follow-ups. - The study involves multiple visits, and participants should be okay with procedures and tests. This trial is important because it may lead to a new treatment option for people with small clogged heart arteries.