What is the significance of a CT coronary angiogram showing severe stenosis in the proximal-mid Left Anterior Descending (LAD) artery, mid Right Coronary Artery (RCA), and mid Posterior Descending Artery (PDA)?

From the Guidelines

The patient should be referred immediately to a cardiologist for further evaluation, likely including invasive coronary angiography with possible percutaneous coronary intervention (stenting) or evaluation for coronary artery bypass grafting depending on the exact anatomy and patient factors, as the CT coronary angiogram reveals significant multi-vessel coronary artery disease with high-risk anatomy. The findings show likely severe stenosis in the proximal to mid left anterior descending artery (LAD), severe stenosis in the mid right coronary artery (RCA), and likely severe stenosis in the mid posterior descending artery (PDA). According to the CAD-RADS 2.0 guidelines 1, this represents a CAD-RADS 4B classification, indicating the presence of three-vessel obstructive disease (>70%), which requires further evaluation with invasive coronary angiography and possible revascularization.

While awaiting definitive treatment, the patient should be started on:

• Dual antiplatelet therapy (aspirin 81mg daily plus clopidogrel 75mg daily or ticagrelor 90mg twice daily)
• High-intensity statin therapy (atorvastatin 40-80mg or rosuvastatin 20-40mg daily)
• Anti-anginal therapy as needed (such as metoprolol 25-50mg twice daily or as directed by the cardiologist), as recommended by the 2014 ACC/AHA/AATS/PCNA/SCAI/STS focused update of the guideline for the diagnosis and management of patients with stable ischemic heart disease 1.

These severe blockages in multiple coronary vessels significantly increase the risk of myocardial infarction and cardiac death, making prompt intervention essential to restore adequate blood flow to the heart muscle and prevent irreversible damage, as highlighted in the 2011 ACCF/AHA/SCAI guideline for percutaneous coronary intervention 1. The use of CT-FFR, as described in the CAD-RADS 2.0 guidelines 1, may also be considered to better define the hemodynamic significance of the stenoses.

Key considerations in the management of this patient include:

• The presence of multi-vessel coronary artery disease with high-risk anatomy
• The need for prompt evaluation and treatment to prevent myocardial infarction and cardiac death
• The importance of optimizing medical therapy, including dual antiplatelet therapy, high-intensity statin therapy, and anti-anginal therapy, as recommended by the guidelines 1.

Overall, the management of this patient requires a multidisciplinary approach, involving cardiology consultation, invasive coronary angiography, and possible revascularization, as well as optimization of medical therapy to improve outcomes and reduce the risk of adverse events.

From the Research

CT Coronary Angiogram Results

The CT coronary angiogram shows:

• Likely severe stenosis prox-mid LAD
• Severe stenosis mid RCA
• Likely severe stenosis mid PDA

Treatment Options

According to the studies, treatment options for coronary artery disease include:

• Percutaneous coronary intervention (PCI) 2, 3, 4
• Coronary artery bypass grafting (CABG) 2, 3
• Medical therapy 3

Comparison of Treatment Options

Studies have compared the effectiveness of PCI and CABG:

• CABG is associated with better survival, lower rates of major cardiovascular events, and repeat revascularization compared to PCI 2
• CABG may differ from PCI by providing "surgical collateralization," prolonging life by preventing myocardial infarctions 3
• PCI techniques, such as thrombus aspiration, direct stenting, balloon angioplasty, and drug-eluting stents, have varied impacts on clinical outcomes 4

Diagnostic Tools

Coronary CT angiography (cCTA) is a valid method to exclude coronary artery disease in patients with a low to intermediate clinical likelihood 5

• cCTA is recommended in symptomatic patients with a low or intermediate clinical likelihood for coronary artery disease 5
• Premedication with beta blockers and nitrates can improve image quality at low radiation exposure 5

Antiaggregant Therapy

The optimal antiaggregant therapy after coronary stenting in patients receiving oral anticoagulants is currently debated:

• Dual-antiplatelet therapy (DAPT) with aspirin and clopidogrel or dual therapy (DT) with oral anticoagulants and clopidogrel may reduce bleeding compared to triple therapy (TT) 6
• No increased risk of major adverse cardiac events was reported with DAPT or DT compared to TT 6