TUESDAY MORNING, April 30, 1985

6:45-8:15 a.m. Simultaneous Breakfast Sessions**

A. MYOCARDIAL PROTECTION

Moderator: Robert W. Anderson, Evanston, Illinois

Background of Myocardial Protection

William A. Gay, Jr., Salt Lake City, Utah

Laboratory Studies in Development of Myocardial Protection

Sidney Levitsky, Chicago, Illinois

Summary

Robert W. Anderson, Evanston, Illinois

B. PREOPERATIVE EVALUATION OF THE PULMONARY RESECTION PATIENT

Moderator: James B. D. Mark, Stanford, California

Evaluation of Cardiac Function

Robert H. Jones, Durham, North Carolina

Evaluation of Pulmonary Function

Richard M. Peters, San Diego, California

Evaluation of Hemostatis

Morris A. Flaum*, New Orleans, Louisiana

C. SURGERY FOR CARDIAC DYSRHYTHMIA

Moderator: Alden H. Harken, Denver, Colorado

Advances in the Surgery of Atrial Arythmias

James L. Cox, St. Louis, Missouri

Surgical Electrophysiology of Ventricular Arythmias

James Lowe*, Durham, North Carolina

Electrophysiologic Basis for Ventricular Arythmias

Alfred Buxton*, Philadelphia, Pennsylvania

8:30 a.m. Scientific Session - Grand Ballroom

16. Surgical Management of Effusive Pericardial Disease: Influence of Extent of Pericardial Resection on Clinical Course

HARTZELL V. SCHAFF*, JEFFREY M. PIEHLER*,

JAMES R. PLUTH, GORDONK. DANIELSON,

THOMAS A. ORSZULAK* and FRANCISCO J. PUGA

Rochester, Minnesota

Surgical drainage of effusive pericardial disease is usually accompanied with pericardial resection to obtain tissue for analysis and to lessen the chance of the late constriction or recurrent effusion. The relationship between the extent of pericardial resection and the development of these late complications has not been studied in detail. From 1960 through 1983, 145 patients with pure pericardial effusive disease underwent operative drainage. The effusions were malignant in 72 patients (49.7%) and benign in 73 (50.3%), the largest benign subgroup having had idiopathic pericarditis (29.0%). The patients were divided into three groups, determined by extent of pericardial resection: complete (removing all accessible pericardium) in 72 patients (49.7%), partial (resection limited by the phrenic nerves) in 36 patients (24.8%), and window (lesser resections) in 37 patients (25.5%). Approach was via left anterior thoracotomy in 118 patients (81.4%), subxyphoid in 13 (9.0%) median sternotomy in 7 (4.8%), and right thoracotomy in 7 (4.8%). Thirty-day mortality was 19.4% for malignancy patients and 5.5% for those with benign effusions (P<0.05). All survivors had immediate improvement in symptoms, and deaths in patients with benign disease were related to underlying cardiac or pulmonary disease. Actuarial one-year survival for patients with malignancy was 23.4% (4.2 months mean) and 85.6% for patients with idiopathic effusions (P<0.001). Survival was not influenced by extent of pericardial resection. Fifteen patients (10.3%) developed late constriction or recurrent effusion, and 6 of these required reoperation. Reoperation incidence was 0%, 0%, and 16.2% for complete, partial, and window procedures respectively (20.8% for transthoracic and 7.7% for subxyphoid windows) P = 0.001. Actuarial probability of reoperation or late complication was greater with window procedures than other resections, both for all patients (P = 0.001) and those with benign disease (P = Q003). Transthoracic complete peri-cardiectomy is the procedure of choice for effusive pericardial disease. Subxyphoid drainage has immediate advantages for selected patients, but has statistically greater chance of late complications. Transthoracic window procedures have unacceptable complication rates and should be abandoned. Given their poor survival, patients with malignant effusions must have individualized management, with therapy determined by the status and responsiveness of the underlying malignancy.

*By Invitation

**No advance registration. Attendance by ticket only. Tickets must be purchased at registration desk by 2:00 p.m. on Monday, April 29, 1985. Price of ticket covers attendance at session and breakfast.

17. Mediastinitis after Cardiac Valvular Operations: Impact Upon Survival

EDSON H. CHEUNG*, JOSEPH M. GRAVER,

ELLIS J. JONES, DOUGLAS A. MURPHY*,

CHARLES R. HATCHER, JR.

and ROBERT A. GUYTON*

Atlanta, Georgia

Mediastinitis after cardiac valve replacement is a dreaded complication with consequent mortality estimated as high as 70%. We have reviewed 2491 patients with cardiac valve operation to assess the impact of mediasti-nitis upon mortality in our institution in the last 10 years.

37 patients (1.5%) developed mediastinitis after valve replacement. All patients required operative intervention for mediastinal infection with positive bacterial cultures. 13 of these patients had other perioperative problems associated with a high mortality independent of mediastinitis: bacterial endocarditis not cured by valve replacement (3), recent pre-operative myocardial infarction (5), triple valve disease with biventricular failure (1), and severe perioperative cerebral damage (3). 11 of these high risk patients died (84.6%).

The impact of mediastinitis upon survival is best evaluated in the remaining 24 patients without high risk perioperative problems. 8 of these patients were managed before 1980 with debridement and irrigation as the primary treatment with 2 hospital deaths (25%). Pectoral or rectus muscle flaps were frequently used after 1980 (flaps in 11 of 16 patients), leading to a significantly short time between diagnosis of infection and hospital discharge free of infection (62 vs. 401 days, p<.05). Only 1 of these 16 patients died. Valve re-replacement for endocarditis was performed in 3 of these 24 patients although 14 of 24 had positive blood cultures.

Mediastinitis after valve operations in the absence of other high risk perioperative problems can be successfully managed. Early debridement and muscle flap closure has led to a 94% survival in 16 patients during the last four years.

*By Invitation

18. Comparison Between Antibiotic Irrigation and Mobilization of Pectoral Muscle Flaps in Treatment of Deep Sternal Infections

YVES LECLERC*, RAYMOND D. MARTIN*,

CATHY P. TONG*, RONALD J. BAIRD

and HUGH E. SCULL Y

Toronto, Ontario, Canada

Between January of 1978 and December of 1983, 41 (1%) of patients (pts.) developed deep sternal infections with mediastinitis after cardiac surgery. Between January of 1978 and December of 1981, 22 of these pts. were treated with debridement, primary wound closure and mediastinal antibiotic irrigation (Group I). Between January of 1982 and December of 1983, 19 pts. were treated with debridement, open "clean" packing and delayed wound closure by the technique of pectoral muscle flap mobilization, preserving the thoraco-acromial pedicle and the pectoral humeral attachments (Group II). The purpose of this study was to compare the results of treatment of deep sternal infection after cardiac surgery with these two techniques.

The peri-operative hemodynamic, operative, functional and pathological profiles of both groups of patients were the same.

The cosmetic and functional results were the same in both groups, as were shoulder girdle and torso mobility. We conclude that either technique is equally effective in the management of patients who develop the serious complication of deep sternal infection with mediastinitis after cardiac surgery.

*By Invitation

19. Post-Infarction Angina: An Expanding Subset of Patients Undergoing Coronary Artery Bypass

ROBERT H. BREYER*, RICHARD M. ENGELMAN,

JOHN A. ROUSOU* and STANLEY LEMESHOW*

Springfield and Amherst, Massachusetts

The development of percutaneous angioplasty and improved antianginal medications have led to generally improved expectations for nonsurgical treatment of coronary artery disease (CAD). Increasingly, coronary artery bypass grafting (CABG) is deferred for low risk candidates while an ever-increasing proporation of patients are referred for surgical treatment of unstable post-infarction angina (UPIA). In order to document the increasing incidence of this indication for CABG and to characterize the patient population and operative results, an analysis of patients undergoing CABG for UPIA (< 30 days of infarct) during two time periods was undertaken: Group I - 1/82 to 12/82, Group II - 9/83 to 8/84. Clinical, angio-graphic and operative data were coded and statistical analysis used to compare the two patient groups, evaluate operative results, and identify risk factors.

Results: The incidence of UPIA as an indication for CABG increased significantly (P<0.01) from the first to second time frame, 8.7% (24/276) to 18% (51/283). Group II patients had t use of IV Ntg (51% vs 20%, P< 0.05) and t no. operated within 7 days of infarct (37% vs 21%, P<0.01). All other variables examined were similar in the two patient groups. Analysis of the combined Group I and II pts (N = 75) indicate the following: transmural/subendocardial - 39%/61%; previous infarction - 60%; extent of CAD: 3 vessel (V) - 76%, 2 V - 21%, 1 V - 3%, left main - 20%; left ventricular (LV) ejection fraction was ≥ 40-27%, ≤ 40-32%, not obtained - 41%; mean LV end diastolic pressure = 19.5%; IABP required preop - 40%; mean interval from MI to CABG = 12 days; no. grafts = 3.3 (1-6). Overall in-hospital mortality was 8% (6/75). Univariant analysis demonstrated ↓ ejection fraction and ↑ no. of grafts to be associated with an t risk of mortality. No other variables were correlated with mortality. Group I patients have mean follow-up of 23 mos. and Group II patients of 7 mos. No late deaths have occurred; 91 % of Group I and 85% of Group II survivors remain in Functional Class I.

Patients with UPIA constitute an ever increasing subset of the 1980's CABG population. Operation can be achieved with satisfactory mortality and excellent long-term outlook compared to less acceptable published results with medical management alone. Preop LV function and extent of disease constitute the major indicators of operative risk.

10:00 a.m. Intermission - Visit Exhibits - Grand Salon

Complimentary Coffee

*By Invitation

10:45 a.m. Scientific Session - Grand Ballroom

20. Expanding the Use of the Internal Mammary Artery to Improve Patency in Coronary Artery Bypass Grafting

ALFRED J. TECTOR, TERENCE M. SCHMAHL*

and VINCENT R. CANINO*

Milwaukee, Wisconsin

Nearly 10 per cent of saphenous vein grafts (SVG) will fail early from intimal hyperplasia after coronary artery bypass grafting (CABG). At 10 years, 35 to 40 per cent of the veins will be occluded and a large portion of the remaining patient SVGs will have angiographically significant atherosclerotic narrowing of 50 per cent or greater. Resistance to initimal hyperplasia and minimal atherosclerosis enhances longterm patency in the internal mammary artery (IMA) graft making it a more desirable bypass conduit. We have attempted to increase overall longterm patency and have placed three or more IMA grafts in 100 patients from October, 1982, through July, 1984. Eighty-seven patients received three IMAs, 12 received four, and one had six. Mobilization, preparation and anastomoses were performed with magnification and microsurgical techniques. There are many possibilities of bypasses and each patient's coronary anatomy as well as sites of lesions are used to select the best combination. None of the patients died early, however, one patient expired late from complications of gangrene of both lower extremities. Three patients had perioperative infarctions. Stress tests were performed in 55 patients and all but one were negative. Five patients had postoperative angiograms and all IMA grafts were patent except a RIMA to the posterior descending artery. This conduit was kinked by the lung. We do not use the attached RIMA to bypass the right coronary artery past the acute margin. One patient complains of angina.

As we gain experience, we are able to place at least three IMA grafts in nearly every patient undergoing CABG. Usually the arteries supplying the anterior, lateral and proximal one-half of the inferior wall of the myocardium can be bypassed with IMA grafts while saphenous vein grafts are used for the right coronary artery and the posterior branches of the circumflex. Multiple IMA grafts will limit the incidence of early and late graft failure and improve survival and longterm results from CABG. It is our procedure of choice.

*By Invitation

21. Longterm Results with Total Replacement of the Ascending Aorta and Re-implantation of the Coronary Arteries

CHRISTIAN CABROL*, A. PAVIE*, P. MESNILDREY*,

I. GANDJBAKHCH*, L. LAUGHLIN and V. BORS*

Paris, France and Loma Linda, California

Sponsored by: PIERRE R. GRONDIN

Miami Beach, Florida

From November 1976 to June 1983, one hundred patients, 84 men and 16 women ranging in age from 13 to 74 years, were operated for aortic insufficiency associated with an aneurysm of the ascending aorta. Twenty patients were in NYHA Class I, twenty-two in Class II, fifty-one in Class III, and seven in Class IV. The surgical treatment in all cases consisted of total replacement of the ascending aorta with a tube graft containing a prosthetic valve and reimplantation of the coronary arteries by an intermediate dacron tube graft according to the technique already reported. In sixty-eight patients there was a dystrophic fusiform aneurysm and in thirty-two, there was a dissecting aneurysm of which nine were operated during the acute phase. The operative mortality for the entire group was 4°7o (4 deaths). All patients but one were followed from three months to six and one-half years (average three years). The late mortality has been 8.3% (8.96). Among the eighty-eight survivors, clinical improvement is readily apparent (98.8% are in Class I or II). Twenty-five patients have been restudied by angiography showing a satisfactory coronary and aortic appearance in all cases with neither stenosis nor aneurysm. 85.1% are alive at three years. In conclusion, the treatment of aortic insufficiency associated with aneurysm of the ascending aorta by insertion of a composite graft and reimplantation of the coronary arteries through an intermediate Dacron tube is a sure method with low mortality and excellent long term results.

11:30 a.m. Address by Honored Speaker - Grand Ballroom

HANDS ACROSS THE OCEAN: GERMAN/AMERICAN RELATIONS IN THORACIC SURGERY

PROFESSOR HANS G. BORST

Hannover, Federal Republic of Germany

12:15 p.m. Adjourn for Lunch

12:15 p.m. Cardiothoracic Resident's Luncheon - Belle Chase Room

*By Invitation