Barlow’s Disease: Treating the Chords, Not the Leaflets, Is Key

Minimally invasive robotic, nonresectional mitral valve repair using neochords in Barlow’s disease is safe, effective and durable. That’s the consensus among Cleveland Clinic cardiothoracic surgeons, who are now using the technique on a regular basis.

“The technique avoids the fibrosis and scarring caused by extensive cutting and suturing,” says one of those surgeons, Per Wierup, MD, PhD. “It results in a larger opening with a lower gradient.”

The procedure can be completed more quickly with a robotic approach than a conventional repair performed with a sternotomy. “Patients tolerate it very well,” Dr. Wierup notes. “They require much less inotropic support and routinely only stay overnight in the ICU. Typically they can be discharged from the hospital after a few days.”

Inadequate repair techniques

Barlow’s disease is one of two types of degenerative mitral valve disease causing mitral regurgitation, the other being fibroelastic deficiency. In contrast to the leaflet and chordal thinning seen in fibroelastic deficiency, Barlow’s is characterized by a large valve with redundant tissue that causes the valve to appear thick and swollen (Figure). A dilated annulus and elongated chords cause the entire valve structure to prolapse into the left atrium.

Figure. Illustration of a representative Barlow’s disease mitral valve with generalized thickening and redundant leaflet tissue.

Surgical correction of the regurgitation in Barlow’s disease offers a survival benefit when compared with optimal medical therapy or valve replacement. Conventional repair techniques used for fibroelastic deficiency have been problematic, however.

“In a conventional repair, the prolapsed sections of the valve are resected,” Dr. Wierup says. “A chordal transfer may be performed, and the remaining valve is reattached.”

A better approach

More than a decade ago, Dr. Wierup began exploring how to improve on nonresectional techniques for Barlow’s disease. The approach treats the chords while leaving the leaflets intact.

“Leakage is caused by valve prolapse due to elongated chords, so we replace these with GoreTex® neochords,” he explains. “Making the chords on the anterior and posterior leaflets different lengths allows the zone of coaptation to be adjusted for perfect results.”

Supportive data from a recent review

Performing the procedure using a minimally invasive, video-assisted robotic technique offers multiple advantages over conventional sternotomy, as demonstrated by outcomes from a recent retrospective review of 102 patients who underwent repair of Barlow’s disease. The results, which Dr. Wierup presented at the 2018 American Heart Association Scientific Sessions last November, included the following:

• No patient in either the sternotomy group (n = 38) or the minimally invasive robotic repair group (n = 64) required valve replacement, and no patient who underwent the minimally invasive robotic procedure required intraoperative conversion to sternotomy.
• There were no perioperative deaths or cases of >1+ mitral regurgitation at discharge in either group.
• There were no significant differences in cardiopulmonary bypass times between the groups.
• More than 6 hours of mechanical ventilation was required by 21 percent of patients in the sternotomy group versus no patients in the minimally invasive robotic repair group.
• Whereas 21 percent of patients in the sternotomy group remained in the ICU more than 24 hours, no patients in the minimally invasive robotic repair group did.
• Average hospital stay was 4 days following minimally invasive robotic repair versus 9 days following sternotomy.
• Postoperative atrial fibrillation occurred in 16 percent of the minimally invasive robotic repair group versus 42 percent of the sternotomy group.
• Freedom from the composite end point of death, reoperation or >1+ mitral regurgitation did not differ between the two cohorts.

New standard of care for most patients

“Since he joined the Cleveland Clinic staff in 2017, Dr. Wierup has shared his techniques with other members of our mitral valve team, increasing the options we make available to treat patients with complex mitral valve disease,” says A. Marc Gillinov, MD, Chair of Thoracic and Cardiovascular Surgery at Cleveland Clinic.

“Minimally invasive repair using robotic assistance is now standard treatment for Barlow’s disease at our institution,” Dr. Wierup notes. “Patients must have a healthy aortic valve and groin blood vessels that are large enough to accommodate the cannulas required for robotic surgery. If their aortic valve is leaking, or their groin vessels are too small, it is safer to perform the repair using a minimally invasive alternative approach. However, this is necessary in only a minority of patients.”