The Role Of Angioplasty In Treating Fibromuscular Dysplasia

Introduction

Fibromuscular Dysplasia (FMD) is a rare and complicated blood vessel disorder defined by abnormal cell growth inside the blood vessels. Mainly, the sturdier and more flexible cells that make up the arteries are substituted with fibrous cells, which are significantly less flexible.¹ Therefore,  the change in the cell quality within arteries results in the stiffening of these blood vessels and an increase in their susceptibility to damage. However, it is worth noting that FMD varies from other vascular conditions because it is not characterised by inflammation or plaque in blood vessels.² 

This syndrome is more frequent in people assigned female at birth (AFAB), and it frequently results in artery tightening and aneurysm formation. While FMD can be located in any body part, it is commonly found in the renal, carotid, and vertebral arteries. An elastic artery in good health will contract and expand in response to the regular pulsations of blood going through it. However, in FMD, an artery could be excessively or insufficiently stiff. Excessive stiffness prevents the artery from expanding when blood flows through it, which raises blood pressure. If this persists, it ultimately leads to hypertension (high blood pressure). Moreover, an aneurysm may develop from an artery that dilates if it is not sufficiently rigid, which is usually referred to as a balloon artery. A common kind of FMD causes the affected area to resemble a string of beads because the middle coat and the thickest layer of the artery, consisting of smooth muscle cells and elastic fibres (the tunica media), alternates between wide then narrow states.³

From asymptomatic cases that are discovered unexpectedly, to severe presentations like hypertension or renal failure, the clinical presentation of FMD can differ mainly between patients. When symptoms are evident, they vary between the type and location of FMD. The symptoms include migraines, pulsatile tinnitus (ringing sound in the ears), and neck pain. More severe symptoms are usually hypertension, strokes, spontaneous coronary artery dissection, and a bruit (sounds resembling whooshing over arteries). 

Due to the rarity of symptoms, FMD is commonly diagnosed after angiograms (imaging for blood vessels) or other medical tests that were conducted for a separate reason. With some patients, FMD is diagnosed after they suffer an aneurysm. To confirm the diagnosis, additional tests are required, and they are mostly different types of angiography. These include: Computed Tomography Angiography (CTA), Magnetic Resonance Angiography (MRA), and Digital Subtraction Angiography (DSA).⁴ 

Understanding angioplasty

 To reduce symptoms and avoid complications that hinder the patients’ quality of life, effective management of FMD is essential. Angioplasty, a minimally invasive surgery that targets artery constriction to restore blood flow, is one of the main therapeutic choices for this disease. 

Angioplasty is a medical practice that works by opening clogged or constricted arteries to allow normal blood flow. A balloon catheter is inserted into the damaged artery as part of this surgery. When the balloon is inflated, the abnormal tissue or plaque blocking the artery is compressed against the arterial walls, widening the lumen of the artery. Stents are tiny mesh tubes that are  used to maintain the decompression of arteries and prevent  any chances of them narrowing again.⁵

Significant artery obstructions that reduce blood flow and result in symptoms of FMD are the main reasons for undertaking angioplasty. Treatments for peripheral artery disease, coronary artery disease, and other forms of vascular anomalies frequently involve this surgery. Angioplasty helps relieve symptoms such as chest pain, claudication (pain caused by reduced blood flow to muscles), and in the case of FMD, hypertension and organ ischemia (low blood flow) by increasing blood flow and lowering artery pressure.⁶

Angioplasty and fibromuscular dysplasia

Due to arterial stenosis and aneurysms, fibromuscular dysplasia mainly affects medium-sized arteries and frequently results in the typical “string of beads” or “wave” appearances in imaging investigations.¹ The carotid (supply blood to the face, brain and neck) and renal (supply blood to your kidneys) arteries are the usual locations for this abnormal vascular pattern; it can also affect other arterial regions. The development of aneurysms and arterial stenosis is the key characteristic of the pathophysiology of FMD, which is illustrated by the proliferation of fibroblasts and smooth muscle cells in the arterial wall. 

In cases where conservative management, such as hypertension medication or lifestyle changes, is ineffective, angioplasty has become a crucial part of the suggested therapy alternatives for FMD. By specifically targeting artery constriction and re-establishing normal blood flow, the technique seeks to ease symptoms. 

Numerous clinical cases have proven that angioplasties are highly effective in treating FMD, as research has shown that this procedure relieves symptoms associated with cerebrovascular(blood flow to the brain) involvement and considerably lowers blood pressure distinctly in people with renal artery FMD. Positive results from the surgery have been reported, including many patients experiencing significant improvement in their quality of life and a lower requirement for continuous long-term medications. 

Advantages and limitations of angioplasty for FMD

Angioplasty benefits FMD patients in several ways. Compared to open surgical treatments, its minimally invasive nature usually results in quicker recovery times and less discomfort. Another important advantage is the potential to offer prompt symptom alleviation, as after the treatment, patients frequently report better blood pressure control and a reduction in related symptoms. Moreover, angioplasty is frequently performed as an outpatient procedure, which adds to its allure as a therapeutic choice.

Nonetheless, angioplasty has certain drawbacks. One of the main worries is the possibility of operative complications and damage to the artery walls, like vessel dissection or perforation.. Despite being somewhat minimal, these risks may have a huge impact on the health of the patient. The potential for restenosis, in which the artery may eventually narrow once more, is another difficulty. In certain cases, people may require further interventions or repeat surgeries to keep their arteries open. Furthermore, not all patients will benefit from angioplasty, especially those with complicated or large FMD lesions that are challenging to treat with the conventional method.

Future directions and research

The field of vascular medicine continues to evolve, with ongoing research exploring new technologies and techniques to enhance the effectiveness of angioplasty in treating FMD. Innovations in balloon catheter design, stent technology, and imaging modalities are paving the way for more precise and successful interventions.⁷ For example, drug-eluting stents, which release medication to prevent restenosis, are being investigated for their potential benefits in FMD treatment.

Additionally, long-term studies are crucial for understanding the durability of angioplasty outcomes in FMD patients. Research focusing on the optimal timing for intervention, patient selection criteria, and combination therapies may help improve treatment strategies and patient outcomes. Collaboration between researchers, clinicians, and patients is essential to advance the knowledge and application of angioplasty in FMD management.

Summary 

In summary, angioplasty plays a significant role in fibromuscular dysplasia treatment, offering a minimally invasive option to address arterial narrowing and improve blood flow. The procedure has demonstrated benefits in alleviating symptoms and enhancing quality of life. Despite its advantages, angioplasty has limitations, including the risk of complications and potential for restenosis. Ongoing research and advancements in technology hold promise for further improving the effectiveness of angioplasty and expanding its application in FMD management. A comprehensive and individualised treatment approach, combined with continued research, will be key to optimising outcomes for patients with fibromuscular dysplasia.