Minimally invasive versus sternotomy approach for mitral valve surgery: a propensity analysis.
BACKGROUND
Over the past decade, minimally invasive (MI) mitral valve surgery has grown in popularity. The purpose of this study was to compare both short- and long-term outcomes of mitral valve repair and replacement performed through a MI versus traditional sternotomy (ST) incision using a propensity analysis approach to account for differences in baseline risk.


METHODS
From January 2000 to December 2008, a total of 1,121 isolated mitral valve operations were performed at our institution (548 ST, 573 MI). Data were retrospectively collected on all patients, and a logistic regression model was created to predict selection to a MI versus ST approach. Propensity scores were then generated based on the regression model and matched pairs created using 1:1 nearest neighbor matching. There were 382 matched pairs in the analysis for a total sample size of 764, or 68.2% of the original cohort. Major outcomes of interest included cardiopulmonary bypass time, cross-clamp time, hospital length of stay, major in-hospital complications, and both short- and long-term survival.


RESULTS
Cardiopulmonary bypass time was 117.1 ± 2.0 minutes in the ST group and 139.7 ± 2.6 minutes in the MI group (p < 0.0001), and cross-clamp time was 79.6 ± 1.5 minutes in the ST group and 83.7 ± 1.9 in the MI group (p = 0.106). The average hospital length of stay was 9.81 ± 0.61 days among ST patients and 7.76 ± 0.37 days among MI patients (p = 0.0043). There was no significant difference in the frequency of major in-hospital complications between groups. The mean duration of survival follow-up was 4.2 ± 2.4 years. There was no significant difference in mortality at 30 days (p = 0.622) or 1 year (p = 0.599). In addition, there was no significant difference in long-term survival between groups (p = 0.569).


CONCLUSIONS
Although minimally invasive mitral valve surgery required a slightly longer cardiopulmonary bypass time, there was no difference in cross-clamp time, morbidity, or mortality, and hospital length of stay was significantly shorter when compared with matched sternotomy control patients.
Division of Cardiothoracic Surgery, Department of Surgery, College of Physicians and Surgeons, Columbia University, New York, New York 10032, USA.
Alexander
A
Iribarne
Mark J
MJ
Russo
Rachel
R
Easterwood
Kimberly N
KN
Hong
Jonathan
J
Yang
Faisal H
FH
Cheema
Craig R
CR
Smith
Michael
M
Argenziano
D005260:Female; D006801:Humans; D007902:Length of Stay; D008297:Male; D008875:Middle Aged; D019060:Minimally Invasive Surgical Procedures / Q000379:methods*; D008943:Mitral Valve / Q000601:surgery*; D057216:Propensity Score; D056346:Sternotomy / Q000379:methods*; D016896:Treatment Outcome