Myocardial protection using HTK solution in minimally invasive mitral valve surgery

Minimally invasive cardiac surgery (MICS) is a safe and satisfactory approach used mainly in mitral valve surgery with excellent results in many centers. Cardioplegia administration can be still a problem, especially when an endoaortic clamp is used. We retrospectively analyzed our early results with histidine-triptophane-ketoglutarate (HTK) solution used for myocardial protection in MICS.

Between February 2003 and February 2004, 8 patients underwent mitral valve surgery using an endo- cardiopulmonary bypass (CPB) system and HTK solution as myocardial protection. The mean patient age was 67.7 +/- 9.2 years, and the preoperative ejection fraction was normal in all patients. Three patients had valve repair and 5 had valve replacement. Mean CPB time was 129.2 +/- 19.4 minutes, and aortic cross-clamp duration was 88.5 +/- 15.4 minutes.

In every case HTK solution was used for only a single dose for cardioplegia at the beginning of the procedure, without any recalls. The heart restarted spontaneously at reperfusion in 6 of 8 cases (75%), and there were no significant modifications in electrocardiogram results or myocardial cytonecrosis enzymes (creatine kinase and its MB fraction) during the postoperative period.

HTK solution is a cold crystalloid cardioplegia solution that has demonstrated its utility in MICS because it provides a safe long cardioplegic arrest time and it reduces the risk of inadequate coronary perfusion due to dislodgement of the endoaortic clamp.