From the Guidelines
Fibromuscular dysplasia (FMD) of bilateral renal arteries is likely to have some genetic components, but it is not considered a purely genetic disorder. The condition is multifactorial, with both genetic and environmental factors playing roles in its development 1. FMD affects women more commonly than men, suggesting possible hormonal influences. The disease involves abnormal cell development in the arterial walls, leading to narrowing, aneurysms, or dissections of the affected arteries.
Key Points
- FMD is a systemic disease, and CT or MRI angiography from head to pelvis is recommended in patients with FMD-RVH 1.
- When FMD affects both renal arteries, it can cause renovascular hypertension, kidney dysfunction, or flank pain.
- Management typically involves blood pressure control, antiplatelet therapy, and in some cases, interventional procedures like angioplasty to improve blood flow to the kidneys 1.
- Renal artery angioplasty without stenting should be considered for patients with hypertension and haemodynamically significant renal artery stenosis due to fibromuscular dysplasia 1.
Diagnosis and Treatment
The diagnosis of FMD is based on imaging tests, such as renal artery Doppler ultrasound, with bilateral assessment of renal arterial resistive index, or abdominal CT angiography, or magnetic resonance imaging (MRI) 1. For patients with bilateral renal artery FMD, it's essential to screen first-degree relatives for the condition, especially if they have hypertension or symptoms suggesting vascular disease. The treatment of FMD involves a multidisciplinary approach, including medical therapy, lifestyle modifications, and interventional procedures.
Morbidity, Mortality, and Quality of Life
The primary goal of treatment is to improve blood pressure control, reduce the risk of cardiovascular events, and enhance quality of life. The management of FMD should prioritize minimizing morbidity, mortality, and improving quality of life, rather than solely focusing on the genetic aspects of the disease. By adopting a comprehensive approach to diagnosis and treatment, patients with FMD can experience significant improvements in their overall health and well-being 1.
From the Research
Fibromuscular Dysplasia of Bilateral Renal Arteries
- Fibromuscular dysplasia (FMD) is a nonatherosclerotic, noninflammatory angiopathy of unknown cause affecting medium-sized arteries, including renal arteries 2.
- The etiology of FMD is multifactorial, including vessel wall ischemia, smoking, hormonal, and genetic factors 2, 3, 4.
- Renal FMD is now considered a systemic disease, and the cause may be genetic, although the exact cause is still elusive 3.
- A strong belief exists that a genetic disorder is the main cause for the pathogenesis of renal artery fibromuscular dysplasia 4.
Genetic Factors
- Genetic factors are thought to play a role in the development of FMD, particularly in young women and children who present with recent severe and/or refractory symptomatic hypertension 3, 4.
- The exact genetic mechanisms underlying FMD are not fully understood and require further research.
Bilateral Renal Artery Involvement
- Bilateral renal artery involvement in FMD is possible, as seen in a case report of a 43-year-old man presenting with acute bilateral flank pain and bilateral renal infarctions due to FMD of bilateral renal arteries 5.
- The presence of bilateral renal artery stenosis due to FMD can lead to significant renal dysfunction and hypertension, highlighting the importance of early diagnosis and treatment.