Clinical value and boundary exploration of drug-coated balloons（I）

Journal: JAMA Cardiology
Published: Online, December 23, 2024
Impact Factor: Approximately 30.0. This journal is one of the top journals in the field of cardiology and enjoys an excellent academic reputation.
Document Type: Clinical Review

I. Core Advantages and Technological Evolution of DCBs: Why “No Implantation”?
1. Core Concept and Advantages: The drug-coated balloon follows the design philosophy of “intervention without implantation.” It delivers an antiproliferative drug (primarily paclitaxel) and excipients coated on the balloon surface rapidly and evenly to the vessel wall during balloon expansion, thereby inhibiting neointimal hyperplasia and preventing restenosis.
Unique Advantages Compared to DES:
No Permanent Implant: This avoids the series of problems associated with the long-term presence of a metal stent as a “foreign body,” such as stent struts affecting normal vascular vasodilation.
Promoting Positive Vascular Remodeling: This feature represents the greatest physiological advantage of DCBs. By removing the “confinement” of a stent, the vessel wall can positively remodel as the drug inhibits hyperplasia, ultimately resulting in late lumen expansion.
Preserving Future Treatment Options: By avoiding the addition of extra stent layers, this approach maintains optimal anatomical conditions for potential future revascularization procedures, such as CABG. It simplifies complex lesions by streamlining interventions in cases like bifurcation and diffuse distal lesions. It also allows physicians to potentially shorten the duration of dual antiplatelet therapy for patients with a high risk of bleeding.

2. Key Technologies:
Drugs and Excipients: Paclitaxel: Paclitaxel is the drug used in the vast majority of currently marketed DCBs. Due to its high lipid solubility, it is rapidly absorbed into vascular tissue and remains in the bloodstream for a long time.
Sirolimus and its analogs: Although they dominate DES, researchers are actively exploring their use in DCBs as a major research and development focus. Newer-generation sirolimus DCBs (such as Magic Touch and SELUTION) overcome their poor lipid solubility and inefficient delivery by using nanotechnology and crystalline coatings. Current evidence shows that these sirolimus DCBs perform comparably to paclitaxel DCBs and, in some cases, even surpass them.
Excipients: They play a crucial role in determining the efficacy of DCBs. They guide the drug, ensuring that it effectively releases from the balloon surface and penetrates the vessel wall during the brief balloon–vessel contact period. Different DCB coating technologies (e.g., crystalline vs. amorphous) directly influence drug release kinetics and clinical efficacy, which explains why various DCBs differ in performance and cannot be regarded as a single type of product.

Figure A: A matrix comparing the effects of DCBs with other devices. While significantly suppressing neointimal hyperplasia, DCBs demonstrate significant advantages in positive vascular remodeling, late lumen expansion, and vasomotor recovery. Meanwhile, DCBs have no beneficial or inconclusive effects on acute occlusive lesions, acute recoil, and various thrombotic events.
Figure B: The interplay between vascular remodeling and lumen area after PCI. This diagram explains why DCBs achieve late lumen expansion. Core formula: Lumen area = vessel area – plaque area.
Three scenarios:
The role of DCBs: By avoiding the “confinement” effect of stents, DCBs facilitate positive vascular remodeling, potentially maintaining or even increasing postoperative lumen area during follow-up.
Positive remodeling (vascular area expansion): Even if plaque is stable or slightly increasing, lumen area can increase due to vessel expansion.
Plaque reduction: Even if vessel area remains unchanged, lumen area can increase due to plaque regression. Negative remodeling (reduction in vessel area): Even when the plaque is stable, the lumen area decreases due to vasoconstriction.