Chronic Coronary Syndrome (CCS)

Diagnosis relies on clinical history, non?invasive functional imaging, coronary CT angiography, and invasive coronary angiography.

Coronary CT angiography (CCTA)

CCTA is increasingly recommended as a first-line diagnostic test for patients with low to moderate likelihood (15–50%) of obstructive coronary artery disease. This is due to its high negative predictive value, making it a highly effective tool for ruling out obstructive CAD in this population. In addition to excluding significant blockages, CCTA also allows for direct visualization of non-obstructive CAD, which can guide the initiation or intensification of preventive therapies.

Functional imaging by stress echocardiography (exercise or pharmacologic) 

Functional imaging is an appropriate first-line diagnostic tool when assessment of myocardial ischemia, viability, or microvascular disease is needed. It is particularly valuable in patients with angina or myocardial infarction, as it allows for the quantitative evaluation of myocardial injury, which is critical for determining appropriate treatment strategies. Compared to CCTA, functional imaging offers superior rule-in power for detecting obstructive coronary artery disease (CAD), especially in patients with a moderate to high likelihood (15–85%) of CAD. Moreover, functional imaging overcomes the limitations of CCTA in specific patient populations, including:

• Older adults with extensive coronary calcification
• Those with atrial fibrillation or irregular/rapid heart rhythms
• Patients with renal impairment or iodine contrast allergies

Invasive coronary angiography 

Invasive coronary angiography is a key diagnostic procedure for ischemic heart disease, including angina and myocardial infarction. It provides a detailed anatomical visualization of the coronary arteries, which supply blood to the heart muscle, and allows for accurate identification of stenosis (narrowing) or occlusion (blockage). This procedure is especially appropriate for high-risk patients, where proceeding directly to invasive coronary angiography without prior non-invasive testing is a reasonable approach. These patients include those with:

• A very high clinical likelihood (≥85%) of CAD
• Symptoms that do not respond to optimal medical therapy
• Angina occurring at a low level of exertion
• Initial evaluation indicating a high risk of adverse cardiac events

The treatment of CCS focuses on relieving symptoms such as chest pain and improving the patient’s quality of life. Initial therapy typically begins with medications like beta-blockers or calcium channel blockers, which help reduce the heart’s workload and improve blood flow. If angina symptoms persist despite these first-line treatments, additional anti-anginal medications—such as long-acting nitrates, ivabradine, nicorandil, ranolazine, or trimetazidine—may be added, either alone or in combination. Regardless of the medications chosen, it is important to regularly assess the patient’s response to therapy. If symptoms are not adequately controlled or if side effects occur, the treatment plan should be adjusted to ensure optimal care.

1) Percutaneous Coronary Intervention (PCI) is a minimally invasive procedure that opens narrowed coronary arteries using a balloon and, if needed, a stent. In patients with CCS, PCI is considered when angina persists despite optimal medical therapy, when high-risk coronary anatomy is present, or when significant ischemia is confirmed. PCI helps relieve symptoms, improve quality of life, and, in select cases, may improve prognosis.

2) Prevention of coronary ischemic events is based on lowering the risk 

of coronary artery occlusion and consequent ACS. Medical event- 

preventing therapies include antithrombotic and lipid-lowering.

Antiplatelet therapy

In patients with atherosclerotic disease of coronary arteries, the standard antithrombotic treatment is single antiplatelet therapy, most commonly with aspirin. If the patient has undergone PCI, dual antiplatelet therapy - typically combining aspirin with a P2Y12 inhibitor - should be administered to prevent stent thrombosis and other ischemic events.

Lipid lowering therapy

In patients with CCS, intensive lipid-lowering therapy is essential to prevent future cardiovascular events. The goal is to reduce LDL cholesterol to below 55 mg/dL and by ≥50% from baseline. High-intensity statins are first-line treatment, and additional agents such as ezetimibe or PCSK9 inhibitors may be added if targets are not met.