Does Patient-Prosthesis Mismatch Affect Long-term Results after Mitral Valve Replacement?

Hiroaki Sakamoto, MD, PhD, and Yasunori Watanabe, MD, PhD

Background: Recently, some articles about patient-prosthesis mismatch (PPM) of the mitral valve have been published. However, the outcome of PPM of the mitral valve remains controversial. The objective of this study was to determine the impact of mitral valve PPM on clinical results after mitral valve replacement (MVR).
Methods and Results: Eighty-four patients underwent MVR from 1992 to 2005. They were divided into a PPM group and a non-PPM group. Preoperative, perioperative, and postoperative variables were analyzed retrospectively. The indexed effective orifice area (IEOA) was provided by postoperative echocardiography and body surface area. PPM was defined as an IEOA of 1.2 cm2/m2 or less, and 25 patients had PPM. Thirty-day mortality was 0% in both groups. Postoperative pulmonary artery pressure and residual mitral valve pressure gradient had no significant differences. There was no significant difference in freedom from recurrence of heart failure or from cardiac death between the two groups.
Conclusion: The present study revealed that PPM does not affect the short- or long-term outcome after MVR. But the clinical result when the definition of PPM is made more severe, such as IEOA of 1.0 cm2/m2 or less, was not examined. Further research is required to establish the allowable range of IEOA. (Ann Thorac Cardiovasc Surg 2010; 16: 163-167)

Key words: patient prosthesis mismatch, mitral valve, heart failure

Department of Cardiovascular Surgery, Hitachi General Hospital, Hitachi, Ibaraki, Japan

Received December 4, 2009; accepted for publication March 3, 2009
Address reprint requests to Hiroaki Sakamoto, MD, PhD: Department of Cardiovascular Surgery, Hitachi General Hospital, 2–1–1, Jonan, Hitachi, Ibaraki, 317-0077, Japan.