What is Barlow's syndrome (Mitral Valve Prolapse)?

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From the Guidelines

Barlow syndrome, also known as mitral valve prolapse, is a heart condition that is often benign and requires no specific treatment, but regular cardiac follow-ups every 1-2 years are typically recommended to monitor the condition. This common condition affects about 2-3% of the population and is characterized by one or both flaps of the mitral valve bulging back into the left atrium during heart contraction 1. The condition occurs because the valve tissue becomes stretchy and floppy due to excess connective tissue or myxomatous degeneration.

Key Considerations

  • Most people with mitral valve prolapse don't need medication, but if symptoms like palpitations occur, beta-blockers such as metoprolol (25-100 mg daily) might be prescribed 1.
  • For those with significant mitral regurgitation, surgical repair may eventually be necessary 1.
  • It's essential to inform your dentist about this condition as antibiotic prophylaxis may be needed before certain dental procedures if you have significant regurgitation 1.
  • Stay hydrated and avoid stimulants like caffeine if they trigger symptoms.

Complications and Risks

  • The gradual progression of mitral regurgitation in patients with mitral valve prolapse may result in the progressive dilatation of the left atrium and ventricle, leading to atrial fibrillation, and moderate to severe mitral regurgitation may eventually result in left ventricular dysfunction and congestive heart failure 1.
  • Infective endocarditis is a serious complication of mitral valve prolapse, which is the leading predisposing cardiovascular diagnosis in most series of patients reported with endocarditis 1.
  • Sudden death is a rare complication of mitral valve prolapse, occurring in fewer than 2% of known cases during long-term follow-up 1.

Monitoring and Prevention

  • Regular cardiac follow-ups every 1-2 years are crucial to monitor the condition and prevent complications 1.
  • Patients with mitral valve prolapse should be aware of the risks and symptoms of complications and seek medical attention immediately if they experience any concerning symptoms.

From the Research

Definition and Causes of Barlow Syndrome

  • Barlow syndrome is a condition characterized by abnormal bulging of the mitral valve leaflets into the left atrium during ventricular systole, also known as mitral valve prolapse 2.
  • Myxomatous degeneration is the most common cause of mitral prolapse in the United States and Europe, and progression of myxomatous mitral prolapse is the most common cause of mitral regurgitation that requires surgical treatment 2.

Surgical Treatment of Barlow Syndrome

  • Minimally invasive mitral valve repair is a viable treatment option for patients with Barlow's disease, with good early and long-term results 3.
  • A stepwise repair strategy can facilitate mitral valve repair in patients with Barlow's disease, providing excellent outcomes even via a minimally invasive approach 4.
  • Annular stabilization can effectively resolve the functional prolapse of the anterior mitral valve leaflet, allowing for a technically less challenging operation that provides excellent repair durability 5.
  • A simple repair approach using ring-only repair has been shown to be effective in patients with Barlow disease and multisegment involvement causing mainly central jet, with excellent late outcomes 6.

Outcomes and Results of Surgical Treatment

  • Successful mitral valve repair was performed in 94.5% of patients with Barlow's disease, with a mean follow-up period of 6.5 years 3.
  • The repair success rate was 100% in patients who underwent stepwise repair, with no patients developing moderate or greater mitral regurgitation during a mean follow-up period of 36 months 4.
  • Freedom from recurrent ≥Grade 2+ mitral regurgitation was 90.7% and 89.1% at 6 years after operation for patients with and without anterior mitral valve leaflet repair, respectively 5.
  • Freedom from recurrent moderate or severe mitral regurgitation was 100% in patients who underwent ring-only repair, compared to 89% in controls 6.

References

Guideline

Guideline Directed Topic Overview

Dr.Oracle Medical Advisory Board & Editors, 2025

Research

Mitral valve prolapse.

Annual review of medicine, 2012

Research

Minimally invasive mitral valve repair in Barlow's disease: early and long-term results.

The Journal of thoracic and cardiovascular surgery, 2014

Research

Simple repair approach for mitral regurgitation in Barlow disease.

The Journal of thoracic and cardiovascular surgery, 2015

Professional Medical Disclaimer

This information is intended for healthcare professionals. Any medical decision-making should rely on clinical judgment and independently verified information. The content provided herein does not replace professional discretion and should be considered supplementary to established clinical guidelines. Healthcare providers should verify all information against primary literature and current practice standards before application in patient care. Dr.Oracle assumes no liability for clinical decisions based on this content.

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