742-4 Radial Artery Graft: Angiographic Follow-up

Interest in the use of the radial artery (RA) as a coronary bypass graft has increased. Attention to harvesting and use of perioperative calcium channel inhibitors have ameliorated problems with spasm noted in earlier studies. Since 1993, 72 patients (pts) underwent grafting using a free RA from the non-dominant forearm. Re-angiography was performed in 24 pts to date and is the subject of this study. Pts ranged from 39–79 years (mean 55.5); all had 2 or 3 vessel disease and an average of 3 grafts/pt were constructed (range 2–4). Left internal thoracic artery (L1TA) was used in all cases except 1. The RA was a single graft in 19 including 2 to the LAD system, 12 to the circumflex system and 5 to the RCA. The RA-was sequential in 5 cases. Of the 24 pts catheterized an average of 9 weeks post-op 24/24 RA's were patent: 1 (sequential) RA had a mid-graft stenosis. There was no spasm seen in any RA. RA distal diameters (2.6mm) were well matched to the recipient vessel (RV) (2.2mm). The ratio RV/graft diameter was 0.83 for the radial artery similar to the ratio for the L1TA (0.90).ConclusionThe RA is a viable coronary conduit, easily harvested and has excellent early patency rates

Routine Use of Unilateral and Bilateral Radial Arteries for Coronary Artery Bypass Graft Surgery

AbstractObjectives. This study sought to evaluate the routine use of radial artery (RA) grafts in patients undergoing coronary artery revascularization.Background. Previous long-term studies have documented poor patency of saphenous vein grafts compared with internal thoracic artery (ITA) grafts.Methods. We performed a prospective review of 175 of 249 consecutive patients.Results. Fifty-four patients had bilateral RAs harvested. Mean number (±SD) of grafts/patient was 3.27 ± 0.93, with 2.76 ± 0.97 arterial grafts; a mean of 1.53 ± 0.68 grafts were performed with the RA. The operative mortality rate was 1.6%. No deaths were related to RA grafts, and there were no RA harvest site hematomas or infections. Transient dysesthesia 1 day to 4 weeks in duration occurred in the distribution of the lateral antebrachial cutaneous nerve in six extremities (2.6%). Elective cardiac catheterization in 60 patients at 12 weeks postoperatively demonstrated a 95.7% patency rate.Conclusions. Because of potential benefit of long-term patency associated with arterial grafts, minimal morbidity and mortality associated with use of the RA and excellent short-term patency rates, we cautiously recommend use of one or both RAs as additional conduits to be used concomitantly with the ITA for arterial revascularization of the coronary arteries

Activation mapping in patients with coronary artery disease with multiple ventricular tachycardia configurations: Occurrence and therapeutic implications of widely separate apparent sites of origin

Catheter or intraoperative activation mapping studies, or both, were performed in 17 patients with coronary artery disease with two to four distinct configurations of ventricular tachycardia, resistant to a mean of 12.1 ± 6.0 antiarrhythmic drug trials per patient. Mapping studies were performed to guide anticipated surgical ablation of arrhythmias. Activation map data were adequate to determine sites of origin of 30 (64%) of 47 observed tachycardia configurations. These 30 ventricular tachycardias (26 observed clinically) were mapped to 22 separate endocardial sites of origin. Sites of origin of distinct tachycardias were identical or closely adjacent (within 3 cm) in six patients and widely separate (≥4 cm) in eight patients (47% of the group). Activation maps were not adequate to determine sites of origin of 17 (36%) of the 47 tachycardias, including all configurations in three patients.Fifteen patients underwent surgery for control of ventricular tachycardia: aggressive, map-guided endocardial resection (mean 26.5 ± 14.2 cm2) in 12 patients with identified sites of tachycardia origin and extensive resection of visible endocardial scar (2 patients) or encircling endocardial ventriculotomy (1 patient) in those in whom the sites of origin of all clinical tachycardias remained undetermined. Two inoperable patients were treated with amiodarone. During postoperative electrophysiologic tests (11 of 13 surgical survivors), ventricular tachyarrhythmias were initially uninducible in only 4 of 11 patients. However, in two patients only nonclinical arrhythmias (ventricular flutter) were induced. Six (21%) of 29 clinical tachycardias whose sites of origin were either not determined or not resected (right septum or papillary muscle) remained inducible in five patients. Using previously ineffective antiarrhythmic drugs, initially inducible arrhythmias became uninducible (two patients), or harder to induce than preoperatively (five patients). As a result of surgical resections alone or in combination with previously ineffective drugs (and amiodarone in two inoperable patients), there were no recurrences of ventricular tachycardia in 14 (93%) of 15 patients discharged during 19.0 ± 14.3 months of follow-up study.Thus, activation mapping may commonly reveal separate apparent sites of origin for clinically observed, morphologically distinct, highly drug-refractory ventricular tachycardias in patients with coronary artery disease with multiple tachycardia configurations. Extensive surgical resection of identified sites of origin may be required to ablate arrhythmias in these patients. Tachycardias whose sites of origin are not identified or resected may remain inducible. However, aggressive surgical excisions may alter regions involved in the genesis or maintenance of these arrhythmias because they become more difficult to induce postoperatively, more amenable to drug therapy and do not recur

Effects of Terrestrial Buffer Zones on Amphibians on Golf Courses

A major cause of amphibian declines worldwide is habitat destruction or alteration. Public green spaces, such as golf courses and parks, could serve as safe havens to curb the effects of habitat loss if managed in ways to bolster local amphibian communities. We reared larval Blanchard's cricket frogs (Acris blanchardi) and green frogs (Rana clamitans) in golf course ponds with and without 1 m terrestrial buffer zones, and released marked cricket frog metamorphs at the golf course ponds they were reared in. Larval survival of both species was affected by the presence of a buffer zone, with increased survival for cricket frogs and decreased survival for green frogs when reared in ponds with buffer zones. No marked cricket frog juveniles were recovered at any golf course pond in the following year, suggesting that most animals died or migrated. In a separate study, we released cricket frogs in a terrestrial pen and allowed them to choose between mown and unmown grass. Cricket frogs had a greater probability of using unmown versus mown grass. Our results suggest that incorporating buffer zones around ponds can offer suitable habitat for some amphibian species and can improve the quality of the aquatic environment for some sensitive local amphibians

Evaluation of Acute Ischemic Mitral Regurgitation Following Cardiopulmonary Bypass Assessed by Biplane Transesophageal Echocardiography

The aim of this study was to evaluate pathogenesis and outcome of acute ischemic mitral regurgitation (MR) in patients undergoing coronary artery bypass grafting (CABG) using biplane transesophageal echocardiography (TEE).　　 Biplane TEE was continuously monitored in a total of 96 patients who were scheduled for elective CABG surgery. Of 96 patients, 10 with no MR at stages 1 (after anesthetic induction but before skin incision) and 2 (after cardiopulmonary bypass [CPBJ and decannulation) were excluded. In the remaining 86 patients with MR between stages 1 and 2, 45 (group A) had an increase in MR, and 41 (group B) had a decrease in MR. An increase in MR・ at stage 2 in group A was associated with a significant increase in annular diameter (p < 0.05), and pulmonary capillary wedge pressure (p < 0.01) compared with stage 1. A significant decrease in the left ventricular end-diastolic area (p < 0.01), end-systolic area (p < 0.05) and the mean wall motion abnormality score (WMA score) (p < 0.001) was observed at stage 2 compared with stage 1 in group B. In 16 of 17 patients (94%) with an increased WMA score in group A, a regional wall motion abnormality (RWMA) was detected in the right coronary artery (RCA) and/or left circumflex coronary artery (LCX) areas. In 7 patients in group A, MR increased continuously until stage 3 (after sternal closure) despite treatment. In 2 of these 7 patients, pulmonary venous systolic flow (PVSF) decreased during stage 2 and persisted to stage 3. The post operative course of these 2 patients was complicated with atrial fibrillation (AF).　　 The increase in annular diameter and worsening in RWMA in RCA and/or LCX areas are associated with acute ischemic MR following CPB. The majority of acute ischemic MR cases were resolved by pharmacological intervention. Post operative AF was noted in 2 patients with acute ischemic MR associated with persistently decreased PVSF following CPB despite treatment.This study was presented in part at the 9th Annual Meeting of the European Association of Cardiothoracic Anesthesiologists, held on June 1-4, 1994 in Turku, Finland, at the 5th Annual Scientific Sessions of the American Society of Echocardiography, held on June 13-15, 1994 in San Francisco, CA, and at the 1994 Annual Meeting of the American Society of Anesthesiologists, held on October 15-19, 1994 in San Francisco, CA