Coronary Surgery

Invasive imaging: the key to treatment

Angiocardiography is a classical X-ray method for examining the heart and major vascular trunks. The principle of this study is based on the direct injection of a special contrast agent directly into the cardiac cavities or the vascular lumen. This is followed by a series of X-ray images. In modern cardiology, this approach is quite deservedly considered the "gold standard". It is the most reliable diagnostic tool because it enables the physician to obtain a direct and clear visualization of the anatomical structure, assess the actual volumes of the heart chambers, and study the nature of blood flow in detail.

Coronary angiography, often called coronarography or CAG for short, is an invasive radiocontrast examination. During this procedure, a contrast agent is injected selectively into the ostia of the coronary arteries under strict X-ray guidance. The procedure is performed in a specially equipped X-ray operating room. The main objective of this method is the reliable detection of areas of narrowing (stenosis) in the coronary arteries, determining their most precise localization and severity.

This method has fundamental diagnostic significance for the management of patients suffering from ischemic heart disease (IHD). Performing coronarography is a strictly mandatory diagnostic step before a final decision is made regarding the need for surgical myocardial revascularization (whether classical coronary artery bypass grafting or endovascular balloon dilation with stenting). Both of these methods belong to the group of direct invasive methods for visualizing the cardiovascular system. This fundamentally distinguishes them from non-invasive techniques (echocardiography, MSCT, MRI). Invasive approaches always require the intravascular administration of an iodine-containing radiocontrast agent followed by real-time X-ray imaging.

Strategy for choosing a revascularization method

The choice of the optimal surgical approach requires consideration of many factors. In the presence of confirmed coronary artery stenosis, the main treatment options are coronary artery bypass grafting (CABG) or percutaneous coronary intervention (PCI), which includes balloon angioplasty and stent placement.

Special conditions for choosing between bypass surgery and stenting arise in patients with stable coronary artery disease. If the anatomical structure of the coronary arteries is technically suitable for either method, and the predicted surgical mortality is assessed as low, surgeons rely on specific classes of recommendations.

The anatomical landmarks when planning the intervention are the key vessels of the heart:

• Left main coronary artery (LMCA) trunk.
• Left anterior descending artery (LAD, also known as the anterior interventricular artery).
• Circumflex artery.
• Right coronary artery.

Decisions are classified by degree of appropriateness:

1. Class I — the procedure is recommended and strictly indicated.
2. Class IIa — the intervention is reasonable.
3. Class IIb — the use of the method may be considered on an individual basis.
4. Class III — the procedure is strictly not recommended.

Features in heart failure and aneurysms

Surgical treatment of patients with chronic heart failure (CHF) accompanied by a low ejection fraction requires a special approach. In such severe clinical situations, coronary revascularization is necessarily considered by attending physicians in order to effectively relieve the distressing symptoms of angina pectoris. Possible options may include arterial stenting, coronary artery bypass grafting under cardiopulmonary bypass, or balloon angioplasty followed by stenting. This is advisable in cases where vascular anatomy allows for the intervention and prominent symptoms persist despite optimal medical therapy.

Special attention should be paid to the algorithm of actions in the presence of concomitant aortic aneurysms. Invasive pressure determination (manometry) and assessment of hemodynamic parameters are far from always required. They are indicated exclusively when data from non-invasive studies have proven insufficiently informative or their results clearly diverge from the observed clinical picture. Performing manometry routinely, simultaneously with coronarography, is strongly discouraged due to the high risk of complications. In addition, panaortography is not recommended if there is a technical possibility to perform computed tomographic angiography (CTA) or magnetic resonance angiography (MRA) of the aorta, as panaortography in this situation has low diagnostic value.

Impact of comorbid pathology on tactics

When planning a coronary intervention, the surgeon evaluates the spectrum of specific cardiac pathology in a particular patient in detail.

• Coronary artery disease: primary coronary symptoms are identified, the time elapsed since myocardial infarction is taken into account, and the exact number of affected vessels is calculated.
• Valvular heart disease: the presence of stenosis or regurgitation on the aortic and mitral valves is recorded, and tricuspid regurgitation is assessed. A dangerous comorbid condition is aortic root abscess.
• Arrhythmias: rhythm and conduction disturbances play a crucial role. Attention is drawn to atrial fibrillation, atrial flutter, life-threatening ventricular tachycardia (VT), and ventricular fibrillation (VF). Sick sinus syndrome (SSS) and 2nd- and 3rd-degree (complete) atrioventricular blocks are also taken into account.
• Previous interventions: factors determining the technical complexity of the operation. These include prior CABG, valve surgery, previous PCI (stenting), and other procedures.

Class and exam questions

What else to study on this topic

• Features of coronary artery anatomy (LAD, LMCA, circumflex) and their impact on the choice of surgical method.
• Detailed differences between percutaneous coronary intervention (PCI) and classical bypass surgery (CABG).
• Classification of rhythm disorders (VT, VF, AV blocks) as surgical risk factors.
• Principles of optimal medical therapy in CHF before and after myocardial revascularization.

Prepared by WhiteCoat Pro faculty in accordance with the medical school curriculum. For educational purposes only.