Heart intertwined with roads, symbolizing CABG vs. PCI for diabetes.

Type 1 Diabetes & Heart Health: Is Bypass Surgery the Best Strategy?

Mira Elwood in Health & Wellness June 2025 • 4 min read.

"New research sheds light on why coronary artery bypass grafting (CABG) might be superior to stents (PCI) for individuals with type 1 diabetes and complex heart disease."

For individuals grappling with aggressive coronary artery disease (CAD), deciding between coronary artery bypass grafting (CABG) and percutaneous intervention (PCI, or stenting) is a critical decision. A growing body of evidence suggests CABG may offer superior long-term survival and reduce the risk of heart attack, especially when CAD is extensive.

Severity often depends on the extent and complexity of CAD, which doctors measure using the SYNTAX score. The presence of diabetes, particularly type 1 diabetes (T1DM), further complicates matters. Studies indicate that CABG tends to yield better results than PCI in these higher-risk scenarios, regardless of whether older balloon angioplasty, bare-metal stents, or newer drug-eluting stents are used.

Now, new research focuses specifically on individuals with type 1 diabetes (T1DM), a group often underrepresented in previous trials that largely focused on type 2 diabetes (T2DM). This article explores why CABG might be a more effective strategy for people with T1DM and complex CAD, diving into the underlying mechanisms and latest evidence.

Why Complexity Matters: The SYNTAX Score and CABG's Advantage

Heart intertwined with roads, symbolizing CABG vs. PCI for diabetes.

One consistent theme emerges when comparing CABG and PCI: CABG's benefits become more pronounced as the complexity and extent of CAD increase. The SYNTAX (Synergy between PCI with Taxus and Cardiac Surgery) score helps quantify this complexity, guiding treatment decisions.

The original SYNTAX trial, involving 1,800 patients with three-vessel or left main CAD, demonstrated that, after five years, PCI led to a significantly higher rate of death, heart attack, or stroke (37.5% vs. 24.2% with CABG). This advantage for CABG was especially evident in patients with intermediate or high SYNTAX scores (≥33), indicating more complex disease.

SYNTAX Score: A tool to categorize the complexity of coronary artery disease.
Low Score (≤22): Indicates less complex disease.
Intermediate Score (23-32): Suggests moderate complexity.
High Score (≥33): Represents highly complex disease.

These findings led to the development of the SYNTAX 2 scoring system, which incorporates both anatomical factors and patient characteristics to provide a more refined assessment and guide personalized treatment strategies.

CABG vs. PCI: The Verdict for Type 1 Diabetes

The study by Nyström et al. reinforces the idea that CABG may be particularly beneficial for individuals with T1DM and multivessel CAD. Their research, analyzing a large cohort of patients in Sweden, revealed that CABG was associated with superior outcomes compared to PCI in terms of heart-related mortality, heart attack, and heart failure.

While this study offers valuable insights, it's important to acknowledge its limitations as an observational study. The PCI group, for instance, tended to be older and have more pre-existing conditions, potentially influencing the results. These factors highlight the challenges of comparing treatments in non-randomized settings.

Ultimately, the decision between CABG and PCI should be made on an individual basis, considering the complexity of CAD (SYNTAX score), the presence of diabetes (especially T1DM), and other patient-specific factors. The growing body of evidence, including the findings, suggests CABG may offer a significant survival advantage for individuals with T1DM and complex coronary disease.

About this Article -

This article was crafted using a human-AI hybrid and collaborative approach. AI assisted our team with initial drafting, research insights, identifying key questions, and image generation. Our human editors guided topic selection, defined the angle, structured the content, ensured factual accuracy and relevance, refined the tone, and conducted thorough editing to deliver helpful, high-quality information.See our About page for more information.

This article is based on research published under:

DOI-LINK: 10.1016/j.jacc.2017.07.781, Alternate LINK

Title: Type 1 Diabetes, Coronary Disease Complexity, And Optimal Revascularization Strategy

Subject: Cardiology and Cardiovascular Medicine

Journal: Journal of the American College of Cardiology

Publisher: Elsevier BV

Authors: Michael J. Domanski, Michael E. Farkouh

Published: 2017-09-01

Everything You Need To Know

What is Coronary Artery Bypass Grafting (CABG), and why is it important in relation to Type 1 Diabetes?

Coronary Artery Bypass Grafting (CABG) is a surgical procedure where a new pathway is created for blood flow to bypass the blocked coronary arteries. This is particularly important for those with Type 1 Diabetes (T1DM) and complex Coronary Artery Disease (CAD), as it may offer superior long-term survival and reduce the risk of heart attack. It involves taking a blood vessel from another part of the body and using it to reroute blood flow around the blockage.

What is the SYNTAX score, and how does it influence treatment decisions for heart disease?

The SYNTAX score is a tool used to measure the complexity of Coronary Artery Disease (CAD). It helps doctors determine the severity of the disease. A low score (≤22) indicates less complex disease, an intermediate score (23-32) suggests moderate complexity, and a high score (≥33) represents highly complex disease. This score is vital because it helps guide treatment decisions, indicating when Coronary Artery Bypass Grafting (CABG) might be more beneficial than Percutaneous Intervention (PCI, or stenting).

Why might Coronary Artery Bypass Grafting (CABG) be a more effective strategy for people with Type 1 Diabetes?

Individuals with Type 1 Diabetes (T1DM) and complex Coronary Artery Disease (CAD) may find Coronary Artery Bypass Grafting (CABG) to be a more effective strategy. Research indicates that CABG can lead to better outcomes compared to Percutaneous Intervention (PCI, or stenting) in terms of heart-related mortality, heart attack, and heart failure. The advantages of CABG are particularly evident in people with T1DM because their condition can complicate heart disease, making CABG a more favorable option for improving long-term health.

What is Percutaneous Intervention (PCI, or stenting), and how does it compare to Coronary Artery Bypass Grafting (CABG)?

Percutaneous Intervention (PCI, or stenting) is a procedure where a stent is inserted into a blocked coronary artery to open it up and improve blood flow. However, in the context of people with Type 1 Diabetes (T1DM) and complex Coronary Artery Disease (CAD), Coronary Artery Bypass Grafting (CABG) has shown to be more beneficial. The benefits of CABG become more evident as the complexity of CAD increases. The SYNTAX score helps to quantify this complexity.

What are the implications of choosing between Coronary Artery Bypass Grafting (CABG) and Percutaneous Intervention (PCI, or stenting) for individuals with Type 1 Diabetes and complex heart disease?

The implications of choosing between Coronary Artery Bypass Grafting (CABG) and Percutaneous Intervention (PCI, or stenting) for people with Type 1 Diabetes (T1DM) and complex Coronary Artery Disease (CAD) are significant. CABG may offer better long-term survival rates and reduce the risk of heart attack and heart failure compared to PCI. This is especially true when the SYNTAX score is high, suggesting a complex disease. Therefore, selecting CABG could lead to improved cardiovascular health outcomes and a better quality of life for those with T1DM and extensive CAD.