SYNTAX trial
SYNTAX trial
1. What was the primary objective of the original SYNTAX trial?
💬 The SYNTAX trial aimed to compare outcomes between PCI with drug-eluting stents and CABG in patients with complex CAD (left main or 3-vessel disease).
2. What type of stent was used in the PCI arm of the SYNTAX trial?
💬 The PCI arm used first-generation Taxus stents, which are paclitaxel-eluting stents.
3. What is the SYNTAX score used to assess?
💬 SYNTAX score is a tool to assess the anatomical complexity of coronary lesions, guiding decisions between CABG and PCI.
4. A high SYNTAX score suggests:
💬 A high SYNTAX score reflects complex disease and higher benefit from surgical revascularization (CABG).
5. Which of the following was a key conclusion of the SYNTAX trial?
💬 The SYNTAX trial concluded that CABG was superior to PCI in patients with complex coronary disease (high SYNTAX score).
6. Which of the following outcomes was significantly higher in the PCI group in SYNTAX?
💬 Explanation: The need for repeat revascularization was significantly higher in the PCI group, especially in patients with more complex coronary anatomy.
7. What patient population showed particularly better outcomes with CABG in the SYNTAX trial?
💬 Explanation: Patients with high SYNTAX scores (>33) had better outcomes with CABG due to the complexity of coronary disease, reduced need for repeat revascularization, and improved long-term survival.
8. What is a key limitation of the original SYNTAX trial?
💬 Explanation: A key limitation was the use of first-generation paclitaxel-eluting stents, which are now considered inferior to newer-generation DES.
9. What does the SYNTAX score primarily assess?
💬 Explanation: The SYNTAX score is an angiographic tool that quantifies the complexity and extent of coronary artery disease, guiding decision-making between PCI and CABG.
10. Which of the following is included in the SYNTAX score calculation?
💬 Explanation: The SYNTAX score incorporates anatomical features of coronary lesions such as location, calcification, bifurcations, and total occlusions to assess overall complexity.
11. In SYNTAX, which subgroup had similar outcomes between PCI and CABG?
💬 Explanation: Patients with low SYNTAX scores (≤22) had comparable outcomes with PCI and CABG, justifying PCI in low-complexity disease.
12. How were patients assigned to PCI or CABG in SYNTAX?
💬 Explanation: The SYNTAX trial was a randomized controlled trial, assigning eligible patients to either PCI or CABG to compare outcomes.
13. What is the main endpoint used in the SYNTAX trial?
💬 Explanation: MACCE was the composite primary endpoint, including death, stroke, MI, and repeat revascularization.
14. Which statement is TRUE about diabetes and SYNTAX?
💬 Explanation: Diabetic patients benefited more from CABG than PCI in terms of long-term survival and reduced MACCE.
15. What is the significance of SYNTAX II?
💬 Explanation: SYNTAX II integrated FFR, IVUS, and second-generation DES to refine PCI strategy and showed improved outcomes.
16. Which artery involvement increases SYNTAX score the most?
💬 Explanation: Left main involvement heavily increases SYNTAX score due to its high-risk location and large myocardial territory.
17. SYNTAX score helps in choosing between:
💬 Explanation: SYNTAX score guides the decision between PCI and CABG in complex coronary artery disease based on lesion anatomy.
18. What is the SYNTAX score II?
💬 Explanation: SYNTAX score II combines anatomical complexity with clinical factors (age, EF, gender, renal function) to individualize PCI vs CABG decisions.
19. Which imaging modality was not used in original SYNTAX?
💬 Explanation: IVUS was not systematically used in the original SYNTAX trial; it was included later in SYNTAX II.
20. What was a major advantage of CABG over PCI in SYNTAX?
💬 Explanation: CABG significantly reduced the rate of repeat revascularizations in SYNTAX, especially in high-complexity lesions.
21. What type of patients were included in the SYNTAX trial?
💬 Explanation: The SYNTAX trial specifically enrolled patients with complex three-vessel and/or left main coronary artery disease to assess outcomes with PCI vs CABG.
22. What is the SYNTAX score designed to assess?
💬 Explanation: The SYNTAX score quantifies coronary artery disease complexity and guides decision-making between PCI and CABG.
| Key Finding | Details |
|---|---|
| Trial Name | SYNTAX (Synergy Between PCI With TAXUS and Cardiac Surgery) |
| Population | Patients with 3-vessel and/or left main coronary artery disease |
| Design | Randomized controlled trial (PCI vs CABG) |
| PCI Stents Used | First-generation drug-eluting (Paclitaxel/TAXUS) stents |
| Primary Endpoint | Major Adverse Cardiac and Cerebrovascular Events (MACCE) |
| Follow-up | 1, 5, and 10 years |
| Mortality Outcome | Lower in CABG, especially for high SYNTAX scores |
| Stroke Rate | Higher with CABG |
| Repeat Revascularization | Significantly higher in PCI group |
| SYNTAX Score Purpose | Stratify coronary complexity; guide treatment |
| Low Score (<22) | PCI and CABG comparable outcomes |
| Intermediate Score (23–32) | Outcomes depend on anatomy and comorbidities |
| High Score (>33) | CABG superior due to reduced repeat procedures |
| Key Limitation | Use of outdated stents |
| Extended Analysis | SYNTAXES (SYNTAX Extended Survival study) |
| SYNTAXES Duration | 10-year follow-up data |
| Diabetes Subgroup | CABG better in diabetics with complex lesions |
| Left Main Disease | CABG preferred in high anatomical complexity |
| Impact | Informed guidelines for revascularization strategy |
| Conclusion | CABG remains standard in complex multivessel CAD |
🧠 Short-Answer Questions (5 points each)
1. What does the acronym SYNTAX stand for?
→ Synergy Between PCI With TAXUS and Cardiac Surgery
2. What stents were used for PCI in the SYNTAX trial?
→ First-generation paclitaxel-eluting (TAXUS) stents
3. Which patient subgroup benefited most from CABG in SYNTAX?
→ Those with SYNTAX score > 33
4. What outcome was notably higher with PCI in SYNTAX?
→ Repeat revascularization
5. Why is the SYNTAX score clinically useful?
→ It stratifies anatomic complexity to guide revascularization
6. What was a key limitation of the SYNTAX trial?
→ Use of outdated drug-eluting stents
7. Which arm had higher stroke rates?
→ CABG group
8. What follow-up period does SYNTAXES cover?
→ 10 years
9. What was the primary endpoint of the trial?
→ Major Adverse Cardiac and Cerebrovascular Events (MACCE)
10. How did the findings influence guidelines?
→ Helped establish CABG as standard for complex CAD
✅ 1. What does the acronym SYNTAX stand for, and what was the primary aim of the trial?
- SYNTAX = SYNergy between PCI with TAXUS and Cardiac Surgery.
- The trial compared PCI using drug-eluting stents vs. CABG.
- It focused on patients with left main and/or 3-vessel CAD.
- Aim: To assess safety and efficacy of each modality.
- Primary objective was to guide optimal revascularization strategy.
✅ 2. Describe the inclusion criteria for patients enrolled in the original SYNTAX trial.
- Patients with de novo 3-vessel or left main CAD.
- Eligible for both PCI and CABG as per heart team consensus.
- Age ≥18 years, suitable for revascularization.
- No prior revascularization procedures like CABG or PCI.
- Willing and able to provide informed consent.
✅ 3. What were the main differences in outcomes between CABG and PCI at 1 year and 5 years?
- At 1 year, MACCE was higher in PCI vs. CABG.
- Stroke was slightly higher in CABG group.
- At 5 years, mortality was lower in CABG (especially high SYNTAX score).
- Repeat revascularization was more common in PCI.
- CABG had more durable outcomes in complex disease.
✅ 4. What is the significance of the SYNTAX score, and how is it calculated?
- Quantifies coronary lesion complexity.
- Higher score = more complex and diffuse disease.
- Based on location, length, calcification, and bifurcation.
- Helps stratify patients for PCI vs. CABG.
- Widely used in clinical decision-making today.
✅ 5. Which subgroup of patients benefited most from CABG in the SYNTAX trial?
- Patients with SYNTAX score >33.
- Those with complex multivessel CAD.
- Left main disease with diffuse involvement.
- Diabetics with high lesion burden.
- Patients with impaired LV function.
✅ 6. What type of drug-eluting stent was used in the PCI group of the SYNTAX trial?
- First-generation drug-eluting stents.
- Specifically, TAXUS paclitaxel-eluting stents.
- These were standard at the time of the study.
- Less effective than newer-generation DES.
- Contributed to higher revascularization rates.
✅ 7. List three key limitations of the original SYNTAX trial.
- Use of outdated paclitaxel-eluting stents.
- Trial not powered to detect mortality differences alone.
- Exclusion of certain high-risk patient populations.
- Operator expertise variability across centers.
- Lack of newer medical therapy comparison.
✅ 8. What were the major components of the composite primary endpoint used in the trial?
- Death from any cause.
- Stroke.
- Myocardial infarction (MI).
- Repeat revascularization.
- Major Adverse Cardiac and Cerebrovascular Events (MACCE).
✅ 9. How did diabetes mellitus influence outcomes in patients undergoing revascularization?
- Diabetics had worse outcomes overall.
- CABG offered better long-term outcomes than PCI.
- Higher rates of repeat revascularization with PCI.
- Diabetics with complex CAD fared better with surgery.
- Led to guideline changes favoring CABG in diabetics.
✅ 10. How has the SYNTAX trial influenced current guidelines for revascularization in multivessel CAD?
- Validated role of heart team decision-making.
- CABG preferred in high SYNTAX score patients.
- PCI considered for low-to-intermediate complexity.
- Influenced ESC and ACC/AHA guidelines.
- Encouraged development of SYNTAX II and III scores.
