Starr-Edwards Valve Replacement Research Articles

Ｓｔａｒｒ‐Ｅｄｗａｒｄｓ弁による小児弁置換術後の遠隔成績 運動機能，弁機能を中心とした多角的検討

Ｓｔａｒｒ‐Ｅｄｗａｒｄｓ弁による小児弁置換術後の遠隔成績 運動機能，弁機能を中心とした多角的検討

Late results after Starr-Edwards valve replacement in children

Selection of types of prosthetic heart valves for children remains controversial. The case histories of 50 children surviving valve replacement with Starr-Edwards prostheses between 1963 and 1978 were reviewed to evaluate the long-term performance of mechanical valves. The 31 boys and 19 girls ranged from 6 months to 18 years in age (mean 10.4 years); 19 patients had had aortic valve replacement, 24 patients had had mitral valve replacement, and one patient had had both. Among the six patients who had had tricuspid valve replacement, four had corrected transposition, so that the tricuspid valve was the systemic atrioventricular valve. Mean (+/- standard deviation) follow-up interval was 7.9 +/- 4.9 years (maximum 17 years). For all patients, the 5 year survival rate was 86% +/- 6%. At 10 years postoperatively, the survival rate (+/- standard error) was 90% +/- 7% after aortic valve replacement and 76% +/- 8% after systemic atrioventricular valve replacement. At follow-up, 39 patients were alive, and 38 were in New York Heart Association Class I or II. Of the 11 deaths, four were valve-related. Seven patients had major (requiring hospitalization) thromboembolic events, and five patients had minor transient neurological symptoms suggesting thromboembolism; 50% of these patients were not taking warfarin (Coumadin) at the time of the thromboembolic event. The incidence of late (greater than 30 days) thromboembolism was 5.3 per 100 patient-years after aortic and 2.0 per 100 patient-years after systemic atrioventricular valve replacement. At 10 years postoperatively, 66% +/- 15% of patients who had had aortic valve replacement and 91% +/- 6% of those who had had systemic atrioventricular valve replacement were free of thromboembolism. The excellent long-term survival, absence of mechanical failure, and relatively low rate of thromboembolism with this prosthesis contrast with our experience with biological valves, in which 41% of children required reoperation in 5 years. Currently, mechanical valves, such as the Starr-Edwards prostheses, are our preferred valves for pediatric patients.

Pathology of heart valve replacement surgery: autopsies of 62 patients with Starr-Edwards prostheses.

Hemorrhage in the atrioventricular conduction system and myocardial necrosis commonly occur in the first week after valve replacement. Later, thrombosis on the prosthesis and infarcts in other organs become important but developing or persistent myocardial damage continuously menaces. Occlusion of small vessels, especially by embolism of foreign material, may contribute to the development of these lesions. Although the extracorporeal circulation, anticoagulation, cardiac pacing and steroid therapy generally applied to patients undergoing Starr-Edwards valve replacement either are necessary to the surgery or effectively overcome some potent dangers, these practices may disguise progression to more serious levels of some maladies induced by operation. Data accumulating from these autopsies and from clinical records include many and varied complications of surgery.

Cardiac hemodynamics immediately following aortic valve surgery

Comments and summary There have been a few reports concerning hemodynamic studies following cardiac surgery. 6, 7, 8 The present study describes a method of obtaining serial hemodynamic profiles on postoperative cardiac patients and presents data from a group of patients with isolated acquired aortic valve disease. Perhaps the most striking finding in this study is that the average patient following Starr-Edwards valve replacement for acquired aortic valvular disease demonstrated essentially normal hemodynamics, despite the fact that all of the patients had been limited by their heart disease preoperatively. Even patients with decreased cardiac indices preoperatively, unless they also had marked left ventricular failure, promptly returned to normal in the postoperative period. Patients with preoperative evidence of marked left ventricular failure, however, and also patients who immediately postoperatively evidenced reduced cardiac indices did not do so well. Many of them evidenced continued low cardiac indices, low systemic blood pressures, and left ventricular failure; all three of the hospital deaths were in this group. There was very little difference following Starr-Edwards valve replacement in patients with predominant aortic stenosis and those with predominant aortic regurgitation. The postoperative hemodynamic data also indicated that coronary perfusion was superior to myocardial hypothermia in its protective effects on the heart and the consequent myocardial performance in the early postoperative period. From the data presented here, there did not seem to be any significant difference between left coronary perfusion and bilateral coronary perfusion.

A Study of Postoperative Aortic Valvular Function by Postmortem Perfusion

SUMMARY AND CONCLUSIONS Twenty patients who died following aortic surgery for calcific aortic stenosis and/or regurgitation were studied. Non-pulsatile and pulsatile postmortem perfusion experiments were carried out to determine the degree of stenosis and regurgitation present. The following conclusions seem justified: (1)In patients who died in the immediate postoperative period following valvuloplasty, stenosis was adequately relieved, but significant regurgitation was present in half the cases. This data indicates that valvuloplasty can frequently result in an initial satisfactory relief of stenosis but also serves to emphasize the importance of correcting aortic regurgitation at operation to avoid fatality. (2)In patients succumbing 12 to 24 months following valvuloplasty stenosis was noted in two of four cases. It seems clear that recurrent stenosis following valvuloplasty may occur with time. (3)In patients dying 9 to 13 months following Muller-Littlefield valve replacement, both stenosis and regurgitation were noted. Regurgitation was due to fracture of the Teflon leaflets while stenosis was associated with leaflet stiffening. (4)In patients with Starr-Edwards valve replacement who died in the immediate postoperative period, no evidence of stenosis or regurgitation was noted.

SPREAD OF THE "MITRAL" SOUND OVER THE CHEST. A STUDY OF FIVE SUBJECTS WITH THE STARR-EDWARDS VALVE.

Five subjects with prosthetic Starr-Edwards valve replacement of the mitral valve were studied in order to delineate the transmission characteristics of the sounds produced by this valve. In sharp contrast to the first (so-called "mitral") component of the first sound, this sound, arising at the mitral ring, arrived earlier on the surface of the chest in the third and fourth left interspaces near the sternal edge as compared to the apex. This was well correlated to the location of the prosthetic valve as seen from roentgenogram of the chest. It is concluded that the transmission of sound from the prosthetic mitral valve is mainly in the form of transverse vibrations. Different transmission characteristics of this sound, as compared to the first component of the first heart sound, indicate a different source for the two sounds.