A novel stentless chordally supported quadrileaflet mitral valve, the Quattro valve, has been in clinical use at our hospital since December 1996. Results of implantation of the Quattro valve in seven patients (average age 34 years) with chronic rheumatic valvular heart disease complicated by active native valve endocarditis, are reported for the first time. Infection was caused by Gram-positive cocci in most patients. Preoperatively, all had congestive heart failure and all underwent early surgery (average seven days from admission). Postoperatively, all were symptomatically improved. No patient required reoperation or has developed early prosthetic valve infection at a mean follow up of 15 months (range: 6-24 months). The performance of the Quattro valve in the setting of active bacterial endocarditis is favorable, as is patient outcome.