Robert J. Flemma

Atherosclerosis of the internal mammary artery.

To better evaluate the incidence of atherosclerosis in the internal mammary artery (IMA), 215 IMA segments from routine postmortem examinations were evaluated microscopically. Significant atherosclerotic narrowing was seen in 9 patients (4.2%). No patient had more than a 50% reduction in lumen diameter. The degree of incipient atherosclerosis correlated well with age, hypertension, diabetes, and peripheral vascular disease.

Comparative Hemodynamic Properties of Vein and Mammary Artery in Coronary Bypass Operations

To understand better the observed differences in bypass flows between vein and internal mammary artery (IMA) grafts, a technique was devised for anastomosing both vein and IMA to the same anterior descending coronary artery in 14 patients. In the stable postperfusion state, flows in the two bypass conduits were simultaneously recorded as well as pressure relationships in both grafts and the left ventricle. The supply/demand ratio for left ventricular performance was calculated with respect to the diastolic pressure-time index/tension-time index (DPTI/TTI) for each bypass independently and simultaneously and then compared. The DPTI/TTI ratio was nearly two times greater with the vein bypass than with the IMA. This difference was further confirmed by the flow studies, in which blood flow through the vein ranged 2 to 3 times higher than IMA flow to the same coronary bed. By present criteria the DPTI/TTI ratio for IMA grafts to the left ventricle was inadequate in the majority of patients studied, and atrial pacing markedly lowered the DPTI/TTI ratio of the IMA. The choice of vein or IMA as a bypass is a critical determinant of the resultant bypass-left ventricular DPTI/TTI ratio. Vein bypasses exhibited far superior hemodynamic capability in the resting state, and the effect of atrial pacing on the DPTI/TTI ratio in IMA-vein-left ventricle bypasses confirms this point.

Results of Intraaortic Balloon Pumping after Cardiac Surgery: Experience with the Percor Balloon Catheter

One hundred thirty-eight patients undergoing an open-heart procedure required an intraaortic balloon pump (IAPB) postoperatively. In Group I (N = 45), the AVCO femoral conduit surgical technique was used; in Group II (N = 93), the Percor balloon was inserted either in the operating room after groin cutdown (open insertion) or percutaneously in the intensive care unit (percutaneous insertion). IABP usage increased in Group II (3% versus 1.6%; p less than 0.001). Immediate mortality was 40% (55/138). Use of the Percor balloon in Group II resulted in lower immediate mortality (32/93 or 34% versus 23/45 or 51%; p less than 0.06). Delayed mortality from multiorgan failure was 11.6% (16/138). Immediate percutaneous insertion at the bedside rather than a return to the operating room for open insertion yielded lower mortality (2/8 or 25% versus 6/7 or 86%; p less than 0.05). Open insertion of the Percor balloon decreases the failure rate of insertion compared with both the AVCO femoral conduit technique (7/85 or 8.2% versus 5/45 or 11%) and percutaneous insertion. It has more complications than the AVCO femoral conduit technique (7/85 or 8.2% versus 2/45 or 4.4%) and less than percutaneous insertion.

Long-Term Follow-up of the Björk-Shiley Prosthetic Valve Used in the Mitral Position

Abstract This study analyzes 547 patients who had mitral valve replacement with a Bjork-Shiley prosthesis over a 9-year period (mean follow-up, 46.5 months). Operative mortality was 7.3%, and 5-year survival was 76.9%. Serious anticoagulation problems occurred in 1.8% (10 patients) and serious thromboembolic episodes in 5.3% (28 patients) (1.3 per 1,000 patient-months). The study includes 257 patients with isolated mitral valve replacement (Group 1) and 290 who had associated procedures (Groups 2 through 5). Hospital mortality in Group 1 was 2.7% compared with 11.7% in Groups 2 through 5 ( p p In the patients in Group 1 with pure mitral insufficiency (MI), 5-year survival was 70.9%, significantly lower ( p Significantly lower ( p

Coronary artery occlusion and blood lipids

Abstract A possible correlation between the levels of plasma cholesterol and triglycerides and the extent of coronary artery occlusion as determined by angiography was studied in 481 male patients. In older patients (over 58 years of age), a pronounced coronary occlusion was frequently found at plasma cholesterol levels which could be considered normal for that age; while in the younger group (less than 48 years of age), extensive occlusive disease was mainly seen in the presence of elevated plasma cholesterol levels. The correlation between plasma triglyceride levels and coronary occlusion seemed to be less pronounced than was the case with plasma cholesterol levels. However, in patients with low cholesterol levels, an increase of plasma triglycerides was associated with more severe occlusive disease.

Prognostic Considerations in the Management of Left Ventricular Aneurysms

This report summarizes a four-year experience with 60 patients who had left ventricular aneurysm (LVA) resection and bypass of all significantly diseased coronary arteries, with an operative and late mortality of 3.3 and 8.3%, respectively. Their cardiac catheterizations were reviewed, and the only values that seemed to reflect prognosis were preoperative cardiac index and the presence of absence of septal motion. The lower the cardiac index, the less likely the patient was to do well postoperatively. There were now survivors who had lacked septal motion by left anterior oblique ventriculogram. Patients without septal motion are therefore no longer considered surgical candidates. If septal motion is present, resection of LVA carries no more risk than myocardial revascularization without LVA.

An Alternative Approach to Isolated Circumflex Coronary Bypass Reoperations

Abstract A method for secondary and tertiary revascularization of circumflex marginal coronary arteries with descending aorta–coronary saphenous vein bypass grafts using an arterial occluder is described.

Ten-Year Follow-up in Aortic Valve Replacement Using the Björk-Shiley Prosthesis

An in-depth statistical analysis of early and late results of aortic valve replacement using the Björk-Shiley tilting-disc prosthesis is presented. Our experience with this prosthesis indicates that replacement carries a low surgical risk, a low incidence of complications (embolization, infection, or hemorrhage due to long-term use of anticoagulants), and good long-term survival. Coexisting coronary artery disease increases surgical mortality significantly, and simultaneous, complete revascularization is essential. Patients undergoing isolated aortic valve replacement did significantly better than those requiring other simultaneous procedures or those who had had previous operations. Earlier operation is imperative since progress of aortic valve disease is unpredictable by duration of symptoms, and patients in New York Heart Association Functional Class II have a low surgical risk and a greatly increased survival. It would appear from this study that additional criteria, such as increasing ventricular dilatation and hypertrophy determined by echocardiographic studies and gated nuclear studies showing deterioration of ejection fraction on exercise, should be used to help determine time of surgical intervention rather than symptomatology alone.

Late Results of Saphenous Vein Bypass Grafting for Myocardial Revascularization

Abstract Data from three large groups of patients undergoing aorta-to-coronary artery saphenous vein bypass grafting with follow-up angiograms between 0 and 32 months and postoperative clinical evaluation for up to 46 months enable us to say there is an early saphenous vein closure rate of 9%. These closures are probably related to technical judgment difficulties and lend themselves to improvement in results. The documented late closure rate in 92 patients followed a mean of 31.7 months was 13%. This is a rate of one late closure per 171 patient-months. Of the 92 patients, 80 had some effective vein graft functioning in this follow-up period. Histological evaluation has revealed subintimal fibrous hyperplasia to be the predominant factor involved in late closure of the vein bypass. Its manifestations are variable, and the multifactorial etiology is as yet unclear. Since 5% of vein grafts have some significant subintimal fibrous hyperplasia at the time of insertion, only close follow-up with correlation of operative, angiographic, and histological data will provide the answers to the question of etiology of late vein graft closure. Studies on the effect of trauma, vascularity, and nutrition of vein grafts are necessary. The answer to this problem will be necessary to set the coronary vein bypass procedure on a firm footing in the treatment of coronary artery disease.

ATHEROSCLEROSIS INVOLVING THE INTERNAL MAMMARY ARTERY

Abstract Three patients undergoing coronary artery bypass operation at this institution over a two-month period were found to have significant atherosclerotic disease involving the internal mammary artery. All 3 patients were relatively young men with hypertension and severe three-vessel coronary involvement. Continuing experience with the internal mammary artery plus subsequent extensive postmortem dissections have supported our impression that atherosclerosis involving the internal mammary artery is much more prevalent than previously implied. Techniques for evaluating this vessel both preoperatively and intraoperatively are discussed.