2:00 p.m. Scientific Sessions - Grand Ballroom

25. Surgical Options for Patients with Sudden Death in Treatment of Ventricular Tachyarrhythmia

EDWARD S. YEE*, MELVIN M. SCHIENMAN*,

JERRY C. GRIFFIN* and PAUL A. EBERT

San Francisco, California and Chicago, Illinois

Ventricular tachyarrhythmias associated with sudden death often fail medical and initial surgical treatment. This high risk group of 62 patients (Pts) presented to the surgical service after failing medical (52) and surgical (10) therapy. Operative treatment by (I) direct revascularization (REV) /11 Pts, (II) endocardial resection (ER) /7 Pts, (III) automatic internal de-fibrillators (AICD) 718 Pts, and in combinations (IV) REV + ER /18 Pts, (V) REV + AICD /5 Pts, and (VI) ER + AICD /3 Pts. Reoperations included redo REV, repeated ER with mapping and mitral valve replacement or papillary muscle re-implantation. The operative risk factors include poor ventricular function with mean ejection fraction of 31%, and recent (less than 1 month) myocardial infarctions (42%, 26/62). Overall operative mortality have been acceptable (8%, 5/62) [i.e., simple procedure (I, II, HI) (2.7%, l/36)as well as combined procedures (IV, V, VI) (15.4%, 4/26)]. These operative deaths include risk factors with recent myocardial infarctions (4/5, <2 weeks) and poor ejection fraction (5/5, <25%). Late follow-up included four deaths (Pts in category (I) and (III)) for an overall 85%, 53/62 survival (mean follow-up of 28 months).

Current surgical treatment of sudden death tachyarrhythmias require a combined operative approach in this high risk group of patients since modality failure with simple REV or ER can occur. Hence, the optimal surgical approach require complete revascularization, localization of arrhythmic focus by endocardial mapping for complete resection, and/or the addition of the automatic internal defribillator.

*By Invitation

26. The Role of Direct Operations in the Management of Life-Threatening Ischemic Ventricular Tachycardia

JORG OSTERMEYER*, MARTINBORGGREFE*,

GUNTER BREITHARDT*, AXEL GOLDMAN*,

JORG D. SCHOENEN*, RALF KOLVENBACH*,

ERHARD GODEHARDT*, JOHN W. KIRKLIN,

EUGENE H. BLACKSTONE and WOLFGANG BIRCKS*

Dusseldorf, West Germany and Birmingham, Alabama

Controversy continues concerning the most effective type of direct operation for life-threatening VT and, in an era in which amiodarone and implantable defibrillators are available, the role of direct surgery in management of patients with VT. In the absence of a randomized trial, the results of a protocol (1978-1985) of intraoperative electrophysiologic mapping and direct surgery (n = 93) have been critically evaluated.

The actuarial freedom postoperatively from spontaneous VT return or sudden death at 30 days, 1 year, and 5 years was 90%, 87%, and 77% respectively. By multivariate analysis a more-or-less encircling myotomy, rather than endocardia! resection, was shown to be more effective against return of VT (p = 0.003). VT return was highly correlated with later premature death. A positive postoperative electrophysiologic study result was a powerful predictor of spontaneous VT return (p = 0.0003).

Survival at 30 days, 1 year, and 5 years postoperatively was 95%, 89%, and 70% respectively. Most patients died of cardiac failure. Endocardial resection was associated with a better survival than was encircling endocardial myotomy (p = 0.002); however, the difference was small, and 5-year survival after endocardial resection was predicted by the multivariate equation to be 88% and after myotomy 85%. Survival was also better in patients in whom an anterolateral aneurysm was present and resected (p= 0.005); in patients with an anterolateral aneurysm, predicted 5-year survival was 85% and without was 31%.

This study supports the continued use of direct operations for VT, suggests the use of encircling myotomy rather than endocardial resection, and provides equations which will facilitate subsequent comparisons with alternative forms of therapy.

*By Invitation

27. Sequential Endocardial Resection for the Surgical Treatment of Refractory Ventricular Tachycardia

IRVING L. KRON*, STANTON P. NOLAN,

TERRY L. FLANAGAN*, BRUCE LERMAN*,

DAVID HAINES* and JOHN P. DiMARCO*

Charlottesville, Virginia

The optimal surgical therapy for refractory ventricular tachycardia (VT) is controversial. The most frequently described operation involves VT induction and endocardial mapping, followed by induction of hypothermia, aortic cross-clamping, and resection of the identified site of VT origin. Our initial experience with this technique in 20 patients [mean age 60 ± 10, ejection fraction (EF) 29 ± 14, failed antiarrhythmic drugs (FAAD) 3 ± 1] resulted in five surgical deaths, three related to VT and two due to respiratory or heart failure. Electrophysiologic study (EPS) showed 11 of 15 survivors free from VT after operation, leaving an overall success rate of 55"%. Most failures were related to multiple VT morphologies not addressed by initial resection. Our results prompted us to modify this operation by employing the technique of sequential endocardial resection. After completion of endocardial mapping, directed normothermic endocardial resection is performed; more attempts to induce VT are made and followed by further mapping and resection until VT can no longer be induced. Forty-seven patients (mean age 59 ± 10, EF 33 ± 12, FAAD 3 ± 1) were treated with this approach, with a mean of two resections per patient (range 1-6). Mean perfusion time in the sequential research group (101 ± 28 min) was not significantly different from that of the earlier cases (101 ± 40 min). There were four (8%) surgical deaths, one related to persistent arrhythmia and three due to respiratory or heart failure. EPS after operation showed 36 of 42 survivors (86%) free of VT. The six with positive EPS were well controlled on medication. These data suggest that sequential endocardial resection guided by intraoperative mapping is a superior operative approach for patients with ventricular tachycardia.

3:00 p.m. Intermission - Visit Exhibits - Wacker Hall

Complimentary coffee available

*By Invitation

3:40 p.m. Scientific Session - Grand Ballroom

28. Long Term Results of Total Coronary Artery Reconstruction

W. DUDLEY JOHNSON, JEROLD B. BRENOWITZ*

and ROBERT GESSERT*

Milwaukee, Wisconsin

Myocardial revascularization has entered a new era of complex surgery. The majority of patients are entering the hospital with diffuse atherosclerotic involvement in one or more coronary arteries. An increasing number of patients are being told they are "inoperable," or offered the option of transplant. The approach of coronary artery reconstruction employed by us is applicable to all diffusely diseased arteries, including those nonvisualized angiographically. The surgical technique used involves long arteriotomies (up to 15 centimeters for the left anterior descending) with careful removal of all involved intima. Reconstruction is achieved by attaching a vein over the entire length of the arteriotomy and then connecting the vein to the aorta. Intermittent ischemic arrest is used with total ischemic time of 180-300 minutes commonly required for reconstruction of many arteries. Since 1978, 3494 procedures have been performed using this technique. Patency, early and late, is only slightly reduced from conventional grafts. There were 2496/2773 (90%) conventional vein grafts restudied within 30 days and found to be patent. A total of 788/888 (89%) endarterectomized arteries were also found to be patent. Patency rates following one year or more were similar as well; 606/807 (75%) conventional vein grafts were found to be patent, while 128/176 (73%) endarterectomized arteries were found to be patent. Multiple endarterectomies and reconstruction adds 6% to the operative risk, but is clearly preferable to failed medical therapy and is often a viable alternative to the proposed transplant.

*By Invitation

29. Immediate (<12 Hour) Vs. Delayed Coronary Grafting After Streptokinase; Non-Linear Time-Dependent Blood Loss and Morbidity

K. FRANCIS LEE*, JONATHAN D. MANDELL*,

J. SCOTT RANKIN*, ROBERT H. JONES*

and ANDREWS. WECHSLER

Durham, North Carolina

Little data exist concerning effects of Streptokinase (SK) on immediate (<12 hour interval) coronary bypass surgery (CBG). 44 patients underwent CBG for acute myocardial infarction. 27 patients received preoperative SK and 17 patients did not (controls). 11 SK patients had CBG <12 hours from thrombolytic therapy. 8 patients between 12-72 hours; and 8 patients >72 hours. Average SK dose was 1.5 x 10⁶. Morbidity included stroke, obtunda-tion, respiratory or renal failure and reoperation.

	(n)	Age	E.F.	# Grafts	% IMA Use	Time CPBP	Blood Loss	Morbidity
Controls	(17)	60.0 ± 2.3	54.1 ± 2.6	2.4 ± 0.4	47%	96.2 ± 10.9	1174 ± 143	13%
SK<12	(11)	61.5 ± 3.6	44.0 ± 2.8*	2.7 ± 0.4	27%	106.1 ± 18.3	2957 ± 567*	50%*
SK 12-72	(8)	58.6 ± 5.1	45.8 ± 5.0	2.9 ± 0.4	38%	99 .4 ± 8.3	1677 ± 244	13%
SK>72	(8)	54.5 ± 2.1	47.3 ± 2.7	3.8 ± 0.6*	38%	155.3 ± 20.7*	1585 ± 300	0%
(Mean ± standard error of the mean.*=p<0.05).

Total blood loss and blood product requirement of Streptokinase patients expressed in ratios over those of controls were as follows:

	Corrected	Corrected	Corrected	Corrected	Corrected
	Blood Loss	PHBC	FFP	PLT	CRYO
SK<12	2.51*	3.07*	2.20*	2.97	10.72*
SK 12-72	1.43	1.98*	1.19	2.57	3.40	*=p<0.05
SK>72	1.35	0.62	1.08	0.72	2.44

Variables in Table I showed only that intervals between SK and CBG <12 hours related to postoperative bleeding and morbidity. Using standard regression analysis, postoperative bleeding and morbidity were not related to age, number of grafts, % IMA usage or cardiopulmonary bypass time. However, the data were consistent with the hypothesis that the effects of SK on postoperative bleeding and morbidity were dependent on time interval between dose administration and operation. CBG >72 hours after SK had no more bleeding than controls despite significantly more grafts and cardiopulmonary bypass time (p<.05). Operations <12 hours from SK resulted in significantly greater bleeding and required more blood products than the control group. Operations 12-72 hours after SK had significantly more blood product requirement than controls without significantly more bleeding, suggesting increased efficacy of bleeding control than in the < 12 hour subgroup.

Significantly increased postoperative bleeding and morbidity occurred in operations <12 hours from SK. Regression suggested that effects of SK on postoperative bleeding and morbidity decrease exponentially with respect to delay time between thrombolytic therapy and operation.

*By Invitation

30. Comparative Effects of Intra-Aortic Balloon Pump, Veno-Arterial Bypass, and Left Ventricular Assist on Reducing Myocardial Ischemic Injury After Acute Coronary Occlusion and Revascularization (Forum)

HIDEO ADACHI*, JAMES D. FONGER*,

DAVID J. JOHNSON*, WILLIAM A. BAUMGARTNER*.

A. MICHAEL BORKON* and BRUCE A. REITZ

Baltimore, Maryland

A combination of adequate circulatory support and medical or surgical re-vascularization is a potential treatment for acute coronary artery occlusion. To evaluate the clinical applicability of assist devices combined with revascularization for acute coronary occlusion, four groups of open chest dogs were studied. In controls (Group I, n = 6), the left anterior descending coronary artery (LAD) was occluded for 90 minutes followed by 180 minutes of reperfusion. In Group II dogs (n = 5), the LAD was occluded and reperfused similarly but an intra-aortic balloon pump (IABP) was activated 15 minutes after occlusion of the LAD. In Group III dogs (n = 5), veno-arterial bypass with centrifugal pump and membrane oxygenator (VAB) was activated 15 minutes after occlusion of the LAD and provided 80% of total flow. In Group IV dogs (n = 6), left ventricular assist using centrifugal pump (LVAD) was activated similarly and provided 80% of total flow. Regional myocardial function in the LAD distribution was examined by computerized pressure dimension loops using sonomicrometry, and functional recovery was calculated. Hypothermic ischemic area in the left ventricle (LV) was measured by real-time infrared imaging to evaluate the extent of ischemic myocardial injury. Following the experiment, region at risk (RR) was determined by manastle blue dye infusion and infarcted myocardium (IM) was examined by nitro blue tetrazolium chloride staining. The results (mean ± SEM) were:

	I (Control)	II (IABP)	III (VAB)	IV (LVAD)
Functional recovery (%)	-6.6 ± 1.9	1.3 ± 3.3	5.3 ± 4.3*	9.7 ± 2.9**
Hypothermic area in LV (%)	31.6 ± 5.2	19.6 ± 4.0	18.2 ± 1.7	14.9 ± 1.8*
Region at risk in LV (%)	29.4 ± 3.6	35.3 ± 3.8	32.4 ± 3.4	29.0 ± 3.4
IM/RR (% Infarction)	57.3 ± 9.2	22.1 ± 5.0*	46.9 ± 8. 8	13.0 ± 4.1**
*p<0.05 vs Control, **p<0.001 vs Control

Group IV showed best function recovery, the smallest hypothermic area, and the smallest myocardial infarction. These results suggest that the combination of revascularization and the early use of a LVAD may be a useful treatment for reducing ischemic myocardial injury after acute coronary artery occlusion.

*By Invitation

31. Systemic-Pulmonary PTFE Shunts in Palliative Congenital Heart Surgery (Forum)

JOSEPH J. AMATO, MARK L. MARBEY*,

JOSE ANTILLON*, CATHERINE BRUSH*,

JOANNE BUSHONG* and JOSE MARIN*

Newark, New Jersey and Philadelphia, Pennsylvania

The concept of central shunting in smaller children with the Waterston Shunt was initially well accepted. It has been abandoned because of difficult estimation of lumen size, preferential flow to the right side and difficulty in the take-down of the shunt. We have replaced the Waterston Shunt with a short segment of polytetrafluoroethylene (PTFE) from the ascending aorta to the main pulmonary artery.

Since January 1979, 174 shunts have been performed in 137 patients. There were 26 classical Blalock-Taussig (B-T) shunts (14.9%), 6 Waterston shunts (3.4%), 9 Glenn Shunts (5.1%), 65 central aorto-pulmonary PTFE shunts (37.3%) and 64 modified Blalock-Taussig (MB-T) shunts (36.7%). PTFE grafts were used for 133 of the 174 (76.4%) shunts. Overall mortality was 14.36%, with 9 early deaths (5.1%) and 15 late deaths (8.6%). Deaths were due to the complex nature of the congenital anomaly and/or definitive surgical repair. The patients weighed from 1.6 kg to 19 kg and ages ranged from one day to 4 years.

We have modified our technique so that: 1) Graft length is less than 0.5 cm and both ends are beveled. 2) The aortotomy is fashioned with a punch. 3) The center of the PTFE graft is never clamped. 4) Heparin is given during the construction of the shunt. 5) Aspirin (lOmg/Kg/day) is administered daily. Patency ranges from 1 to 4 yrs.

We conclude that the PTFE shunt provides excellent palliation and that the central shunt, in the smaller child and infant, offers the benefits of shunting without distortion of the peripheral pulmonary arteries.

AN HISTORICAL VIGNETTE

Lyman A. Brewer, III, Pasadena, California

4:40 p.m. EXECUTIVE SESSION (Members Only) - Grand Ballroom

7:00 p.m. PRESIDENT'S RECEPTION - Regency Ballroom

*By Invitation