Earle B. Kay

Internal Mammary Artery Bypass Graft—Long-term Patency Rate and Follow-up

Abstract Between December, 1968, and January, 1974, 814 internal mammary artery and 351 saphenous vein bypass graft procedures were performed in 628 patients. Operative mortality during the past 3 years has been 1.7%. Internal mammary artery bypasses were performed to the anterior descending, circumflex, obtuse marginal, distal right, and posterior descending right coronary arteries. Ninety-one patients having 137 internal mammary artery and 32 saphenous vein grafts were studied angiographically 12 to 36 months postoperatively. All but 2 internal mammary artery bypasses were patent, a patency rate of 98.5%; 27 of the 32 saphenous vein bypasses in this group were patent (84.3%). The majority of the internal mammary artery bypasses were to distal coronary arteries, while the saphenous veins were used primarily for proximal anastomosis. Cineangiographic volume/flow studies were also performed. The average flow in the more distal internal mammary artery bypasses was 61 ml. per minute as compared with 91 ml. per minute in the proximal saphenous vein grafts.

Internal mammary retractor

A new retractor for dissection of internal mammary arteries is described. We have found that the instrument can easily be applied to the chest wall and gives excellent exposure for dissection of the graft from origin to bifurcation.

Correction of Mitral Insufficiency under Direct Vision

The incompetent valves in the majority of patients with mitral regurgitation can be surgically corrected by the technics described above. The ease and effectiveness of the correction are largely dependent upon the severity of the pathologic process. The roles of chronic myocarditis, myocardial failure, pulmonary vascular sclerosis, and the presence of other valvular defects are important factors in the eventual result. Fortunately, the abnormality in the majority of valves can be corrected, and the myocardial reserve is usually sufficient to provide satisfactory function. With continued progress in this field, earlier surgical intervention, and probably less severe disease from improved treatment, better results can be anticipated in the future.

Corrective Surgery for Tetralogy of Fallot Evaluation of Results

Fifty patients with tetralogy of Fallot have had surgical correction of their complex defects made possible by the open technic during the past 5 years. The overall 5-year operative mortality was 18 per cent. This was reduced to 15 per cent during the past 2 years in 20 patients. Forty-one of the patients are alive, asymptomatic, and have normal physical activity. Ffteen patients have had cardiac evaluation studies including cardiac catheterization from 1½ to 3 years postoperatively. Thirteen patients had normal cardiac hemodynamics. In only two patients was there evidence of incomplete hemodynamic improvement even though marked clinical improvement was gained.

Mitral stenosis: Comparative analysis of postoperative results following the closed and open operative approach

Abstract The postoperative benefit obtained in patients with mitral stenosis operated upon by the closed technic was compared to that obtained by the open technic as evidenced by electrocardiographic, radiographie and hemodynamic evaluation studies. Superiority of results was noted following the open technic in each category. The operative mortality and morbidity for comparable lesions were not only no greater by the open technic but the versatility of the open approach allowed correction of many defects that could not have been corrected by the closed approach. The superiority of the results of the open technic were such that if the facilities and experience for open operation are available, there should be no question as to its use.

Surgical treatment of mitral stenosis

Abstract With accumulated experience, it became increasingly apparent that maximal valvular correction by the closed technic was not possible or entirely successful because of subvalvular stenosis, calcification or aggravation of regurgitation. One hundred and six patients have now had valvular correction by means of the open approach employing extracorporeal circulation with far greater improvement than previously provided by the closed approach. Postoperative physiologic studies demonstrated marked hemodynamic improvement and greater valvular correction by the open technic in twice as many patients with mitral stenosis as the closed technic.

Surgical treatment of aortic valvular disease by prosthetic replacement

Abstract Forty-two patients with aortic valvular disease, twenty-eight with regurgitation, eight with calcific stenosis and six with multivalvular disease, have had surgical correction by means of an artificial plastic valve. The low operative mortality (five early and three late deaths from possible avoidable complications) and the marked benefit received, attest to the superiority of prosthetic replacement over previous partial or palliative technics in the surgical correction of these lesions.

Results of surgery for ventricular septal defects

Abstract The surgical correction of ventricular septal defects can be accomplished today by teams experienced in extracorporeal perfusion technics with a minimum of risk and a maximum of effectiveness. There has been no operative mortality during the past two years in the series reported, regardless of the degree of pulmonary hypertension. With this degree of success it is believed that patients with significant shunt flows (40 per cent or more) should have the shunts closed without waiting for the development of enlarged hearts, increased pulmonary vascularity and pulmonary hypertension. Operative intervention is delayed in infants less than one year of age or less than 20 pounds in weight because of the increased risk.

The role of surgery in the treatment of mitral regurgitation

Summary To date 146 patients with pure and combined mitral regurgitation have had surgical correction. The sustained benefit derived in over 80 percent of the patients so treated lends enthusiasm for this surgical approach to this otherwise progressively deteriorating disease. Further improvement in the remaining 30 percent of the patients not significantly hemodynamically improved in the past is dependent upon earlier surgical intervention and greater improvement in the efficacy of surgical technics. Success in the surgical correction of valvular dysfunction is dependent upon a thorough understanding of the fundamentals of valvular pathology and physiology, continued improvement in the effectiveness of surgical technics and their employment made possible by a highly proficient surgical team and extracorporeal circulation to enable the surgeon ample time for contemplative surgical correction at a time in the disease process that greatest improvement can be anticipated.

Isolated ventricular septal defects: An anatomic-hemodynamic correlation∗

Previous associations between size and location of ventricular septal defects and hemo-dynamics have been based on antemortem physiologic and postmortem anatomic observations. The present study is based on pre-operative and operative observations in vivo in twenty-six patients. Size of defect is shown to be the major determinant of hemodynamic abnormality. The index of relative size (measured diameter of defect/maximum cardiac diameter) shows a good correlation with right ventricular systolic pressure; the regression of this correlation enables approximate prediction of defect size. Relative shunt flow (shunt fraction of pulmonary blood flow) distributes parabolically in relation to right ventricular systolic pressure. A plot of this distribution can be divided into five segments. These demonstrate correspondence of clinical and anatomic findings: 1. Segment 1 (shunt flow < 50 per cent; right ventricular systolic pressure < 60 mm. Hg): diameter of defect 1 cm. or less; corresponds to “maladie de Roger.” 2. Segment 2 (shunt flow > 50 per cent; right ventricular systolic pressure < 60 mm. Hg): defects 1 to 1.5 cm. in diameter; increased pulmonary flow with left ventricular overload. 3. Segment 3 (shunt flow > 50 per cent; right ventricular systolic pressure 60 to 90 mm. Hg): defects 2 cm. or more in diameter; pulmonary congestion and combined ventricular overloading. 4. Segment 4 (shunt flow > 50 per cent; right ventricular systolic pressure > 90 mm. Hg): defects 2 cm. or more in diameter; clinically compensated but with right ventricular overloading. 5. Segment 5 (shunt flow 90 mm. Hg): defects 2 cm. or more in diameter; imminent cardiac failure with severe right ventricular hypertrophy. Surgical repair is indicated for patients in segments 2, 3 and 4. The data clarify suggested mechanisms in ventricular septal defects and provide a basis for predictions of defect size and operability.