American Association for
Thoracic Surgery
55th Annual Meeting
Scientific
Program
MONDAY MORNING, APRIL 14, 1975
8:30 A.M. Business
Session (Limited to Members) Imperial Ballroom
8:45 A.M. Scientific
Session Imperial Ballroom
1. Evidence That Revascularization by Ventricular Internal Mammary
Artery Implants Increases Longevity-Twenty-Three Year Follow-Up
ARTHUR M. VINEBERG,
Montreal, Canada
Relief of anginal pain by ventricular internal
mammary artery implants was originally our objective. In the past 24 years we
have documented 93 cases with patent arteries forming mammary coronary
anastomoses, of which 12 were living on their mammary artery implants only.
Bigelow, Hooper and Effler have reported similar cases. This we consider is
objective evidence of the value of revasculariza-tion surgery. Some of these
cases will be shown.
Further
evidence of the value has been reversal of chronic left ventricular failure
following mammary artery implants. Throughout the years we have reported a
progressive number of cases which now totals 89 in which 67% have had chronic
left ventricular failure successfully reversed. Details of these cases will be
presented.
In addition
we would like to present proof of longevity following ventricular mammary
artery implants. We have surveyed 65 cases of which 47 have been followed up to
23 years. Operative mortality-4 (6%), late deaths-23, these cases lived 2 - 17½
years, average survival 8 years, improvement-78%. Of the 47 cases 20 were still
living at time of survey from 2.5 - 20 years, average survival 12 years, with
91% improvement. In this group 19 internal mammary arteries were studied, 17
(88%) showed mammary coronary anastomoses. In 6 (35%) the mammary artery was
the only artery open in the heart from 3.5 - 17½ years averaging 7.8 years,
after implantation. Details to be given.
Another
series of 42 patients with triple and quadruple coronary artery main stem
disease that underwent right and left ventricular internal mammary artery
implants have been surveyed. The time after surgery averaged 5 years. Operative
deaths-1 (2.4%), late deaths-3 (7.1%). Thirty-eight (90.5%) survived an average
of 5 years. Details to be given. This series can be compared with Humphries
series of 47 patients known to have triple coronary artery disease that were
treated medically. There were only 25 patients (53%) that were alive at the end
of 5 years.
2. Myocardial
Scintography - Post Vineberg Study
F. R. BEGG*, M. H. ADATEPE*,
M. I. SALVOZA*,
and G. J. MAGOVERN,
Pittsburgh, Pennsylvania
In order to
assess the late results (3-5 yrs.) of Vineberg Implants, tracer microspheres
(TM99c)were injected into the internal mammary artery implants of
seven patients after selective contrast visualization. The arteriographic
findings were classified as 1) open - communication with the coronary arteries
2) open -no communication with the coronary arteries 3) closed. The myocardial
scinto-grams were recorded in four positions - PA, LAO, RAO and Left Lateral.
For comparison, direct visualization plus myocardial scintography were
performed on patients with patent saphenous vein and internal mammary artery
grafts.
Areas of
perfusion demonstrated by myocardial scanning correlated with the
arteriographic findings. Open implants with communication to the coronary
arteries produced homogenous densities on myocardial scanning. Open implants
with no communication demonstrated small areas of myocardial scanning. Closed
implants demonstrated no myocardial perfusion.
Patients
with open implants communicating with the coronary arteries were compared to
those patients with patent saphenous vein and internal mammary artery grafts.
The internal mammary myocardial scintograms demonstrated a wider myocardial
distribution of Tracer Microspheres (TM).
We conclude
that patent internal mammary implants with communication perfuse the myocardium
at the pre-capillary or capillary area as demonstrated by the myocardial
distribution of the Tracer Microspheres (TM).
*By invitation
3. Coronary Artery Surgery Improves Survival in Patients with Extensive
Coronary Artery Disease
DANIEL J. ULLYOT*, JUDITH
WISNESKI*,
ROBERT W. SULLIVAN* and
EDWARD W. GERTZ*,
San Francisco, California
Sponsored by Benson B. Roe,
San Francisco, California
Survival in
patients with ischemic heart disease is closely related to the extent of
coronary artery obstruction as determined angiographically.
One hundred
forty-nine consecutive patients underwent coronary artery bypass surgery from
November 1971 to October 1974. There was one hospital death, two late
non-cardiac deaths, and one late cardiac death giving an operative mortality of
0.7% and a total mortality of 2.6%. The coronary angiograms were scored
according to the method of Friesinger, Page and Ross. Fifty-two percent
(77/149) had scores of ten or greater. Survival was analyzed according to the
life table technique.
The
cumulative survival at three years in the 77 operated patients with scores of
ten or greater was .98. Friesinger's 46 non-operated patients with similar
angiographic scores had a 3 year cumulative survival of .66.
Although
this study compares different groups, the surgical series was composed of older
patients (mean age 51 c.f. 41) and includes 36 patients operated on for
pre-infarction angina pectoris.
These data
suggest that coronary artery bypass surgery can favorably influence prognosis
in patients with severe coronary artery disease.
4. Selection of Coronary Bypass: Anatomic, Physiologic and
Angiographic Considerations of Vein and Mammary Artery Grafts
ALEXANDER S. GEHA, JOHN R.
McCORMICK*
and ARTHUR E. BAUE, St.
Louis, Missouri
In an attempt to improve an early (2 weeks
postoperatively) aortocoronary vein graft (ACVG) patency rate of 84% prior to
1973, we have used internal mammary-to-coronary artery grafts (IMAG) when
possible. This study summarizes the results in 106 patients who received 242
grafts since January 1973. Twelve patients had ACVG s only (29 grafts) while 94
received one or two IMAG's with or without additional ACVG's, using in 24 a
crossed double IMA (left IMA to left anterior descending (LAD), right IMA to
diagonal or marginal) to take advantage of the location and direction of the
artery to be bypassed. Thirty-one patients with pre-infarction angina had
IMAG's and all survived and did well.
Flows measured after bypass
were not significantly different between ACVG's and IMAG's (61 ± 8 and 58 ± 7
ml/min.), but flows in crossed right IMA to diagonal or marginal vessels were
significantly higher than in right IMA to right or LAD vessels (50 ± 7 v/s 32 ±
7 ml/min, p<0.01). In 12 patients with both ACVG and IMAG, there was no
difference in the flow response of either graft to vasoactive drugs
(isoproterenol, epinephrine and phenylephrine). Graft flow did not correlate
with either mean arterial pressure or cardiac index. Early angiographic patency
was 99% for IMAG's and 86% for ACVG's. The only IMAG occlusion was due to a
clip on the proximal vessel which was corrected later. Twenty-six patients with
IMAG's, including 8 with double IMA's, were studied 3 to 16 months
postoperatively with patent mammary grafts in all.
We conclude
that IMAG's yield higher patency and comparable flow rates to ACVG's and should
be used when feasible. Graft flow is primarily dependent on the distal vascular
bed rather than the conduit. When grafts to the LAD and high diagonal or
marginal are required, the advantages of crossed IMAG's are: 1) better
alignment of left IMA with LAD and right IMA with the diagonal or marginal
without torsion; and 2) reduced length of each graft with a larger caliber of
IMA at the anastomosis. IMA grafting is also a safe and feasible approach for
pre-infarction angina.
INTERMISSION - VISIT
EXHIBITS (Albert Hall)
*By invitation
5. Acute Myocardial
Infarction: A Surgical Emergency
R. BERG,
JR., L. W. RUDY*, J. H. GANJI*,
R. W. KENDALL*,
F. J. EVERHART*, G. E. DUVOISIN*,
Spokane,
Washington
Preservation of viable myocardium is the
primary goal of coronary artery surgery. Our total direct coronary surgical
experience of 1024 cases (2.7% mortality) includes 55 patients with evolving acute
myocardial infarctions who were catheterized within an average of 5 hours from
the onset of pain. Emergency coronary bypass surgery was carried out with 2
deaths (3.6%). Patients had fewer ventricular arrhythmias and shorter hospital
stays than medically managed patients.
Postoperative cardiac catheterization showed
98% of the primary vein grafts to be patent. Followup studies up to 3 years
after operation show no late deaths by actuarial analysis. Medical management
of 275 patients under age 65 with acute myocardial infarction at our hospital
has a mortality of 14.2% which approaches national averages. The lower surgical
mortality coupled with the early and late clinical results indicates that
emergency coronary bypass is superior therapy in selected patients with acute
myocardial infarction.
6. Acquired
Ventricular Septal Defects: The Evolution of an Operation, Surgical Technique
and Results
J. DONALD HILL, DARREL
LARY*,
WILLIAM KERTH and FRANK
GERBODE,
San Francisco, California
Myocardial
infarction resulted in VSD's treated surgically in 19 patients between 1959 and
1974 at the Pacific Medical Center. The pre-operative pathophys-iological
characteristics were:
1) Murmur developed in less than 48 hrs. of
infarction: 57% (11/19).
2) Single coronary artery disease: 60% (9/15).
3) VSD location: apex, 36%; posterior, 36%;
anterior, 15%; middle, 10%.
4) Infarct location:
anterior septal, 39%; posterior septal, 38%; anterior septal and inferior, 23%.
5) Associated aneurysm: 42% (8/19).
6) Cardiac Index: Mean 1.4 I/ml, Range 1.2-2.5
1/m2.
Eight
patients (Group 1), treated prior to 1970, had surgical principles applied
similar to the correction of congenital VSD's. The results were poor. Treatment
in Group 2 (11 patients) had new closure techniques more consistent with the
pathology of the lesion. These principles are:
1) Apical VSD's: amputate apex.
2) All others repair through the left
ventricular infarct: right ventricle is not opened.
3) The patch is applied only to the left side
of the septum.
4) No foreign material on the right side of
septum.
5) The VSD closure sutures are brought to the
outside of the right ventricle wall.
6) The right ventricular wall is sutured
against the right side of VSD. They heal together.
7) Outside teflon felt bolsters are used to
support the sutures.
8) Aneurysms are excised. Left ventricular
stroke volume is preserved.
9) Re-vascularization.
There was
one survivor in Group 1 (13%). Seven patients survived in Group 2 (64%),
including 5 of the last 6 patients. Survival was not related to the timing of
surgery or to the location of the VSD. Excising the aneurysm and the size and
condition of the remaining left ventricle are important determinants of the
outcome.
Six of the
eight survivors are living normal lives. Post operative heart cathe-therization
results will be presented. One patient has a residual shunt and one died at 8
months with bi-ventricular failure.
Surgical
treatment following new surgical principles has changed a hopeless lesion into
one with a more favorable outcome.
11:15 A.M. Presidential
Address
A
TIME FOR INSIGHT AND REFLECTION
Wilfred
G. Bigelow
*By invitation
