Variant angina, also known as vasospastic angina, is a form of chest pain caused by temporary spasms of the coronary arteries, which reduce blood flow to the heart. These spasms often occur at rest and may lead to serious complications, including life-threatening heart rhythm problems and sudden cardiac death. While most patients improve with medications such as calcium channel blockers and nitrates, some continue to have symptoms despite treatment. In addition, some patients are unable or unwilling to take medications regularly, which further limits effective management. These cases are referred to as medication-refractory or drug-intolerant variant angina.

The autonomic nervous system, which controls involuntary functions like heart rate and blood vessel tone, is believed to play an important role in the development of coronary artery spasms. Recent research suggests that imbalances in autonomic activity, particularly excessive parasympathetic signals, may trigger these spasms.

Cardioneuroablation (CNA) is a minimally invasive procedure that uses a catheter to target specific nerve clusters called cardiac ganglionated plexi, located on the surface of the heart. These plexi are important centers of autonomic control and are mostly made up of parasympathetic nerve cells. Originally developed to treat conditions such as fainting spells and certain types of abnormal heart rhythms, CNA works by selectively reducing abnormal parasympathetic activity in the heart.

This study is designed to explore whether CNA can help relieve chest pain and reduce coronary spasms in patients with variant angina who do not respond to medications or cannot take them consistently. The study will evaluate the safety, practicality, and potential benefits of this approach as a new treatment option for a difficult-to-manage heart condition.

Inclusion Criteria:

• age between 18 and 80 years;
• variant angina;
• positive ergonovine provocation test;
• refractory to antispasmodic drug therapy, or inability to achieve adequate symptom control due to drug intolerance, poor adherence, or unwillingness to take medications regularly.

Exclusion Criteria:

• cardiogenic shock;
• chronic heart failure;
• life expectancy less than 12 months;
• current participation in another clinical study without completing the primary endpoint visit; inability to provide informed consent;
• women of childbearing potential without effective contraception or who are breastfeeding;
• coronary artery stenosis ≥50% or FFR ≤0.80;
• sick sinus syndrome or high-degree AV block without pacemaker;
• systolic blood pressure <90mmHg or heart rate <50 bpm;
• allergy to diltiazem, nitrates, or nitroglycerin.