Do people with arrhythmias still need stents or bypass? 

Arrhythmias and coronary artery disease are two distinct but frequently overlapping heart conditions. An arrhythmia refers to an irregular, too fast, or too slow heartbeat caused by electrical issues in the heart. Stents and bypass surgery, however, are treatments designed to address physical blockages in the coronary arteries. While they treat different problems, the two often coexist, and managing one frequently requires addressing the other. 

For many patients, an irregular heart rhythm is actually a symptom of underlying heart disease. If the heart muscle is not receiving enough oxygenated blood due to blocked arteries, its electrical system can become unstable, leading to an arrhythmia. This article explains the clinical relationship between these conditions and why structural interventions like stents or bypass surgery remain vital for patients with rhythm disorders. 

What We’ll Discuss in This Article 

• The clinical link between blocked arteries and irregular heart rhythms 

• Why treating coronary artery disease can sometimes resolve arrhythmias 

• When a stent is necessary for a patient already using a pacemaker or ICD 

• The role of bypass surgery in preventing life threatening heart rhythms 

• How myocardial ischaemia acts as a primary trigger for electrical instability 

• Differentiation between electrical heart issues and plumbing heart issues 

• Post operative management for patients with combined cardiac conditions 

The relationship between blood flow and heart rhythm 

The heart’s electrical system relies on a constant, healthy supply of oxygenated blood to function correctly. When coronary arteries become narrowed by plaque, the heart muscle can become ‘ischaemic’, meaning it is starved of oxygen. This stress can interfere with the cells responsible for sending electrical signals, leading to common arrhythmias such as atrial fibrillation or ventricular tachycardia. 

In the UK, clinicians often investigate whether an arrhythmia is being ‘driven’ by a lack of blood flow. If diagnostic tests like an angiogram reveal significant blockages, a stent or bypass may be the most effective way to stabilise the heart’s rhythm. Benefits of addressing the physical blockages include: 

• Improved Electrical Stability: Restoring blood flow can stop the irritation of the heart muscle that causes extra beats. 

• Prevention of Scarring: Stopping further damage to the heart muscle reduces the risk of permanent rhythm issues. 

• Enhanced Device Efficacy: If a patient has a pacemaker, it often works more effectively when the heart muscle itself is well nourished. 

When stents are required for arrhythmia patients 

A stent is often required for an arrhythmia patient if their irregular rhythm is accompanied by symptoms of angina or if they have suffered a heart attack. Even if the arrhythmia is being managed with medication or a device, a critical blockage in an artery still poses a risk of sudden cardiac events. In these cases, the stent addresses the plumbing problem while medications manage the electrical problem. 

Research indicates that for certain patients, performing an angioplasty to insert a stent can significantly reduce the frequency of arrhythmia episodes. Clinical teams prioritise stenting for: 

• Patients with Atrial Fibrillation and Coronary Disease: Reducing the heart’s workload by improving flow. 

• Emergency Situations: When a sudden arrhythmia is caused by an acute blockage or heart attack. 

• Pre-Ablation Preparation: Ensuring the heart is healthy before undergoing procedures to zap the electrical pathways. 

The role of bypass surgery in rhythm management 

Coronary Artery Bypass Grafting (CABG) is often the preferred choice for arrhythmia patients who have multiple blocked arteries or complex disease. Unlike a stent, which opens a single point of blockage, a bypass creates a new route for blood, providing a more comprehensive improvement in blood supply to the heart muscle. 

UK clinical guidelines frequently suggest that for patients with both severe coronary disease and certain arrhythmias, combining bypass surgery with a rhythm procedure (such as a Maze procedure for atrial fibrillation) offers the best long-term outcome. This dual approach addresses: 

• Widespread Ischaemia: Protecting large areas of the heart muscle from electrical instability. 

• Long Term Durability: Providing a lasting solution for patients whose arrhythmias are triggered by chronic low blood flow. 

• Heart Failure Prevention: Maintaining strong heart contractions, which helps keep rhythms regular. 

Causes of arrhythmias in heart disease patients 

Arrhythmias in patients with coronary artery disease are primarily caused by changes in the heart muscle tissue. When blood flow is restricted, the muscle cells can become damaged or replaced by scar tissue (fibrosis). This scar tissue does not conduct electricity like healthy muscle, creating short circuits in the heart’s wiring. Common causes include: 

• Myocardial Infarction: Previous damage creating permanent electrical roadblocks. 

• Chronic Ischaemia: Long term oxygen deprivation causing the heart cells to become hypersensitive. 

• Electrolyte Imbalances: Often seen in heart disease patients taking certain medications, which can further destabilise the rhythm. 

• Structural Changes: An enlarged or weakened heart stretching the electrical pathways. 

Triggers for rhythm issues in coronary patients 

For someone with known heart disease, certain physical and environmental factors can act as triggers that push a stable heart into an arrhythmia. Identifying these triggers is a key part of the safety guidance provided by NHS cardiology teams. Triggers often involve: 

• Physical Exertion: When the heart demands more blood than the narrowed arteries can provide. 

• Emotional Stress: A surge in adrenaline can provoke fast heart rhythms in a vulnerable heart. 

• Stimulants: Excess caffeine or alcohol can irritate the heart’s electrical system. 

• Viral Illness: Infections can cause inflammation of the heart muscle, leading to temporary rhythm changes. 

Differentiation: Electrical vs Plumbing issues 

It is helpful to view the heart as having two distinct systems: the plumbing (arteries) and the wiring (electrical system). While they are connected, a problem in one does not always mean a problem in the other, but they often influence each other. Understanding this difference helps patients understand why they might need different types of treatment. 

• Plumbing Issues: Blockages in the coronary arteries. Treated with stents, bypass surgery, and cholesterol medication. 

• Electrical Issues: Faults in the heart’s timing or rhythm. Treated with pacemakers, ICDs, ablation, and beta blockers. 

• The Overlap: Many patients require a combination of both treatments to ensure the heart is both structurally sound and electrically stable. 

Conclusion 

Arrhythmia patients often still require stents or bypass surgery if their rhythm disorder is rooted in underlying coronary artery disease. By restoring blood flow to the heart muscle, these procedures can significantly improve electrical stability and reduce the risk of future cardiac events. A comprehensive treatment plan that addresses both the plumbing and the wiring of the heart is the most effective way to ensure long term cardiac health. 

If you experience severe, sudden, or worsening symptoms, such as a racing heart, intense chest pain, or sudden dizziness, call 999 immediately. 

Authority Snapshot  

This article was written by Dr. Stefan Petrov, a UK-trained physician with an MBBS and extensive experience in general medicine, surgery, and emergency care. Dr. Petrov is certified in Advanced Cardiac Life Support and has hands-on experience in performing diagnostic procedures and managing patients in intensive care environments. His expertise ensures this content provides medically accurate and safe guidance that aligns with NHS and NICE standards for integrated cardiac care.