New Threshold Set for Valve Surgery

"We know from previous studies that patients with symptomatic mitral regurgitation are at increased risk of death, but for those without symptoms the picture has been murkier,” says Maurice Enriquez-Sarano, M.D., the Mayo Clinic cardiologist who led the study. "In this study we followed a large population of asymptomatic patients prospectively to identify keys to improved long-term outcomes, and to determine when patients should consider surgery.”

The Mayo Clinic researchers used Doppler echocardiography to determine which physical characteristics predicted patient outcomes. Age and diabetic status were strongly associated with poorer outcomes. However, the most important finding was that the effective regurgitant orifice area was the strongest determinant of outcome.

Patients with a regurgitant orifice larger than 40 mm2 who were treated only with medication were more than five times more likely to die than those with the same severity of regurgitation who underwent valve repair surgery.

Sarano says the quantitative data from this study, combined with advances in surgical techniques and improved surgical results, help define at what severity of regurgitation patients should strongly consider valve surgery. "The mortality for valve surgery is very low, but it is not zero,” Sarano explains.

"Previously, with patients who were asymptomatic, we had no well-defined quantitative method to determine when the risk of continuing to rely on medication alone exceeded the risk of surgery. Now we have a threshold established through this large study, where continuing medical management carries a much higher risk and surgery can restore normal life expectancy,” he adds.; Source: Mayo Clinic