The left main coronary artery (LMCA) is the main vessel that supplies the left side of the heart and feeds approximately 75% of the heart muscle. Disease in this critical vessel can be treated with bypass surgery or stenting.
What is the Left Main Coronary Artery?#
The left main coronary artery (LMCA) is a critical vessel that emerges from the aorta and divides into two main branches after a short distance:
- Left Anterior Descending Artery (LAD): Supplies the front wall of the heart
- Circumflex Artery (Cx): Supplies the side and back wall of the heart
LMCA disease is seen in approximately 5-7% of patients undergoing coronary angiography and is a high-risk condition.
Importance of Left Main Coronary Disease#
Why is LMCA disease critical?
- Supplies a large portion of the heart muscle
- High risk of sudden cardiac death
- Poor prognosis if untreated
- May require emergency intervention
Symptoms#
Symptoms of left main coronary disease:
- Severe chest pain (angina)
- Shortness of breath increasing with exertion
- Easy fatigue
- Palpitations
- Sudden loss of consciousness (syncope)
⚠️ Warning: Emergency intervention is required in unstable angina or acute coronary syndrome!
Diagnosis#
Coronary Angiography#
Gold standard in diagnosis of left main coronary disease:
- Degree of stenosis (50% and above is significant)
- Lesion location (ostial, shaft, bifurcation)
- Distal vessel quality
Intravascular Imaging#
IVUS (Intravascular Ultrasound):
- Lesion characterization
- Minimal lumen area measurement
- Stent optimization
OCT (Optical Coherence Tomography):
- High-resolution imaging
- Plaque structure analysis
Functional Assessment#
FFR (Fractional Flow Reserve):
- Determines functional significance of stenosis
- FFR ≤0.80 indicates significant stenosis
Treatment Options#
Bypass Surgery (CABG)#
Traditionally the standard treatment for left main coronary disease:
Advantages:
- Long-term results proven
- Preferred in complex anatomy
- Complete revascularization
Disadvantages:
- Open heart surgery
- Long recovery time
- Surgical risks
Left Main Coronary Stenting (PCI)#
Minimally invasive treatment with modern stent technology:
Suitable Patients:
- Low-intermediate SYNTAX score (<33)
- Isolated LMCA disease
- High surgical risk patients
- Patient preference
Technical Features:
- Drug-eluting stents (DES)
- IVUS/OCT guidance
- Bifurcation techniques
- Optimal stent expansion
Left Main Coronary Stenting Techniques#
Ostial and Shaft Lesions#
Relatively simple technique:
- Single stent placement
- Optimization with IVUS
- High-pressure balloon expansion
Bifurcation Lesions#
Requires more complex techniques:
Provisional Stenting:
- Stent to main vessel
- Balloon/stent to side branch if needed
- Most commonly preferred technique
Two-Stent Techniques:
- Culotte technique
- DK-Crush technique
- T-stenting
- TAP (T and Protrusion)
Intravascular Imaging Guidance#
IVUS/OCT use is critical in left main stenting:
- Lesion assessment
- Stent sizing
- Stent expansion control
- Complication detection
Stenting or Bypass?#
The decision is made individually:
| Factor | Stenting Preferred | Bypass Preferred |
|---|---|---|
| SYNTAX score | <33 | ≥33 |
| Lesion | Isolated/simple | Complex/multivessel |
| Diabetes | No | Yes |
| Surgical risk | High | Low |
| Life expectancy | Short | Long |
Left Main Stenting Risks#
Procedure risks:
- Death (1-2%)
- Myocardial infarction (2-3%)
- Need for emergency bypass (<1%)
- Stent thrombosis (rare)
- Restenosis (5-10%)
Post-Procedure Care#
After left main stenting:
In Hospital:
- Intensive care monitoring
- ECG and enzyme monitoring
- Access site control
After Discharge:
- Dual antiplatelet therapy (at least 12 months)
- High-dose statin
- Risk factor control
- Regular angiographic follow-up
Frequently Asked Questions#
Is left main coronary disease dangerous?
Is stenting as effective as bypass?
How long should I take medication after left main stent?
Is control angiography necessary after stenting?
Does the left main stent last a lifetime?
Appointment and Contact#
If you would like to schedule an appointment for left main coronary disease evaluation or treatment:
📍 Avrasya Hospital - Beştelsiz Mah. 101. Sokak No:107, Zeytinburnu, Istanbul
📞 Phone: +90 212 665 50 50 (Ext: 4012)
This content has been prepared by Assoc. Prof. Dr. Habib Çil for general informational purposes. Please consult a cardiology specialist for definitive diagnosis and treatment.
Related Coronary Interventions#
Other coronary treatments related to left main coronary stent:
- Coronary Angioplasty - Balloon and stent vessel opening
- Cardiac Angiography - Coronary artery imaging