A 53-year-old male with ankylosing spondylitis presented with worsening exertional dyspnea. Echocardiography revealed severe aortic regurgitation and an aortic valve replacement was performed using a mechanical valve (SJM Regent 21 mm) in consideration of his age. By the 5th postoperative week, the patient exhibited signs of worsening heart failure. On the 52nd postoperative day, intermittent prosthetic valve regurgitation was detected on echocardiography. Valve fluoroscopy revealed that the valve intermittently remained fixed in the open position, leading to a diagnosis of prosthetic valve dysfunction. Contrast-enhanced CT revealed no evidence of thrombus or tissue formation around the prosthetic valve. On the 56th postoperative day, a redo aortic valve replacement was performed with another mechanical valve (On-X 21 mm). Intraoperatively, no obvious structural abnormalities were identified. Compression of the pivot may have contributed to the dysfunction. We report a rare complication associated with a mechanical prosthetic valve.

The combined method of antegrade and retrograde administration of cardioplegic solution has been established for coronary bypass surgery. We applied this technique in patients undergoing aortic and mitral valve surgery. Between January 1989 and December 1990, 28 patients underwent both aortic and mitral valve replacements. To compare the myocardial protective effect according to the method of cardioplegic administration, they were divided into two groups; Ante group (antegrade, n=15) and Retro group (combined method of antegrade and retrograde, n=13). Aortic occlusion time and cardiopulmonary bypass time were shorter in Retro group. The mean interval of each cardioplegic administration was significantly shorter in Retro group (Ante group, 29.2±4.8min vs Retro group, 24.0±3.8min; p<0.01). These results suggest that retrograde cardioplegia method never disturbs ongoing operation during each delivery while antegrade method often does. Serum CPK-MB at 6hr of reperfusion tended to be less in Retro group (Ante group, 120±80IU/l vs Retro group, 78±50IU/l; p=0.09). The results of postoperative cardiac functions were the same in both groups. We therefore believe that this method is an optimal strategy even in patients with valvular heart disease.