Back to Annual Meeting Program
2:00 P.M. ScientificSession
Ballroom
25. The Role of Physicians' Assistants in aUniversity Teaching Service
CHARLES R. HATCHER, JR., and WILLIAM H.FLEMING,*
Atlanta, Ga.
Trainingprograms in Thoracic and Cardiovascular Surgery currently face a number ofsignificant problems. These include 1) The well documented problem of too manytrainees. 2) Increasing clinical loads in a number of centers resulting in theobvious need for a large cardiovascular surgical team, traditionally expandedby the appointment of additional residents and fellows and 3) A less than idealutilization of Thoracic Surgical trainees in the performance of routine tasksof limited teaching value unless the Service is adequately supported by internsand residents from a General Surgical Service.
In an attempt to meet these problemsPhysicians Assistants were added to the Thoracic and Cardiovascular SurgicalService of Emory University last year. These Physicians Assistants function ascareer junior house officers. Their appointment has resulted in an increase inthe quality and quantity of patient care and has greatly improved the morale ofthe Thoracic Surgical House Staff.
Details of our Physicians Assistantstraining, utilization, compensation, supervision and liability will bepresented. The use of these para-medical personnel in a University TeachingService is considered quite promising at our Institution.
26. TheSurgical Treatment of the Wolff-Parkinson-White Syndrome
WILL C. SEALY and ANDREW G. WALLACE,*Durham, N.C.
Among42 patients with severely symptomatic Wolff-Parkinson-White Syndrome (WPW)admitted to our hospital, 23 were treated with drugs, four had a cardiacpacemaker inserted, and 15 had an operation for division of the bundle of Kent.This report will be concerned principally with our experience with the lastgroup which consisted of seven type B's and eight type A's. The indications forsurgery were a disabling supraventricular tachycardia in 10 and a chaoticventricular rhythm with syncope in five. The location of the Kent bundle wasdetermined at surgery by epicardial mapping of ventricular activation times. Inthe first 10 patients, the approach to the bundle, after displacing thecoronary vessels, was through the atrioventricular groove at the point ofearliest epicardial activation. In nine the pre-excitation was corrected. Inthe two type B failures, the bundle probably penetrated the annulus fibrosus atthe septum; while, in the four unsuccessful type A's, the bundle was adjacentto either the right or left trigone, and thus inaccessible by the externalapproach. In the last five patients a new uniformly successful intra-atrialapproach has been used, which permits Kent bundle division anywhere around theright or left annulus fibrosus. This has made it possible to offer surgery toall patients with WPW, who have either disabling or life threatening symptoms.
27. Distribution of Intramyocardial Blood FlowDuring Pericardial Tamponade: Correlation with Microscopic Anatomy and Determinationsof Intrinsic Myocardial Contractility
ANDREW S. WECHSLER,* BURT J. AUERBACH,*
THOMAS P. GRAHAM,* and DAVID C. SABISTON,JR.,
Durham, N.C.
It is generally thought that pericardialtamponade causes hemodynamic alterations solely by impeding venous filling andsubsequent low cardiac output. In a series of experiments on a canine model forproducing acute tamponade, the changes in coronary blood flow and its role inaccelerating the cardiac failure that accompanies this condition were investigated.In a group of 13 anesthetized dogs subjected to controlled cardiac tamponade,radionuclide labeled micro-spheres (8-10�) were used to determine totalmyocardial blood flow (cc/gm/min) and its distribution between thesubepicardium and the subendocardium. Simultaneous determinations of intrinsiccontractile state were made by processing a high fidelity left ventricularpressure signal through an analogue computer that gave on-line plots ofcontractile element velocity (Vce) and dp/dt against instantaneousleft ventricular pressure. Myocardial sections, stained for succinicdehydrogenase, were examined for subendocardial hemorrhage and the presence orabsence of zonal lesions. These data were compared with a group of 13 dogssubjected to hemorrhagic shock at the same pressure levels used in thetamponade study. At the same aortic pressure, coronary blood flow was asignificantly smaller proportion of the cardiac output in the tamponade group(2.18 �0.22) than in the shock group (13.4+0.92), All animals with tamponadehad a statistically significant selective decrease in subendocardial bloodflow. Those animals with the greatest redistribution of blood flow(endo/epi-ratio 1.05 control going to 0.47 with tamponade) also developedsubendocardial hemorrhages. Intrinsic myocardial, contractile state was greaterwith early tamponade but fell significantly during late tamponade. Thesestudies suggest that increased intrapericardial pressure during pericardialtamponade may accelerate the cardiac manifestations by direct reduction incoronary blood flow, as well as by reducing the driving pressure.
28. The Malignant Potentiality of Left AtrialMyxoma
RAYMOND C. READ, WM. H. FLANAGAN,* MARVINL.
MURPHY,* HAROLD J. WHITE,* and G. DOYNEWILLIAMS,
Little Rock, Arkansas
In 1966Firor et al reported to this Association that simple excision was adequate forleft atrial myxoma. The next year Gerbode first described recurrence andsuggested partial excision of the atrial septum with the tumor.
We wish to report three consecutivepatients who following this procedure have returned with recurrence. The first,a 61 year old male, has an expanding sternal mass and soft tissue lesions inhis back and a filling defect in the pelvis and vertebral column 10 years afteroperation. No evidence of atrial recurrence but biopsies showed myxomatousmetastases. The second had a large recurrence arising broadly from theposterior atrial wall two years after atrial septa) excision. The third wassuccessfully reoperated for mitral insufficiency with valve replacement oneyear after excision of a myxoma. Multiple implantations were found on theleaflets.
Review of the literature reveals 8 otherinstances of atrial recurrence of myxoma. Our experience emphasizes theimportance of implantation in other parts of the atrium and the mitral valve.It documents invasion of myxomatous emboli and it indicates that these tumorsmust be treated more radically than originally thought. The bi-artrial exposureof Cooley with multiple filtration of emboli dislodged during surgery can bestrongly recommended. The malignant potentiality of these "slow" growing tumorsis only now being recognized with increasing experience and longer follow-up.
3:30 P.M. Executive Session (Limited to Active andSenior Members)
Ballroom
TUESDAY EVENING, APRIL 23, 1974
7:00 P.M. President'sReception Ballroom
8:00 P.M. President'sDinner and Dancing
Ballroom
Attendance open to all physicians andtheir ladies. Tickets must be obtained at the registration desk by 5:00 P.M. onMonday, April 22, 1974.
Dinner dress preferred.
