Nose spray before stent surgery may shield heart

Copied word for word from the study's registry entry, so the wording is the study team's rather than ours.

Inclusion Criteria: * Aged between 18 and 85 years old; * Subjects are fully informed of the risks, benefits and alternative treatment regimens of intranasal dexmedetomidine administration. Written informed consent is signed by the subject themselves or their legal representative prior to any study-related procedures; * Confirmed diagnosis of coronary artery disease with objective evidence of myocardial ischemia or silent myocardial ischemia, and indications for elective percutaneous coronary intervention (PCI); * American Society of Anesthesiologists (ASA) physical status classification II to III (patients with mild to severe systemic underlying diseases; ordinary physical activities are markedly limited, yet mild daily activities can be performed). Exclusion Criteria: * Subjects with hypersensitivity or contraindications to dexmedetomidine, including severe sinus bradycardia (resting heart rate \<50 beats per minute), sick sinus syndrome, and second-degree or higher atrioventricular block without pacemaker implantation; * Severe cardiac dysfunction (left ventricular ejection fraction \<40%), New York Heart Association (NYHA) class III-IV heart failure, cardiogenic shock, or hemodynamic instability; * Poorly controlled hypertension (systolic blood pressure \>180 mmHg or diastolic blood pressure \>110 mmHg), or hypotension (systolic blood pressure \<90 mmHg); * Coexisting obstructive sleep apnea hypopnea syndrome (OSAHS); * Body mass index (BMI) \>30 kg/m²; * Use of agents that may interfere with the study drug within 1 week before surgery, including α₂ adrenergic receptor agonists (e.g., clonidine), receptor antagonists, and tricyclic antidepressants; * Cognitive assessment cannot be completed due to language, visual or hearing impairment; * Hepatic or renal insufficiency (alanine aminotransferase, aspartate aminotransferase, or serum creatinine exceeding 3 times the upper limit of normal reference values); * Nasal anatomical abnormalities that preclude intranasal spray administration; * Pregnant or breastfeeding women; * Participation in other conflicting clinical trials.