Notes: Increasing numbers of patients with extensive coronary artery disease present for surgical revascularization. Diffuse atherosclerosis of the anterior descending artery remains a significant challenge and endarterectomy may be required to increase graft outflow. A surgeon may choose local endarterectomy or be accidentally forced into endarterectomy when attempting to split a lesion distal to a critical stenosis. Distal traction endarterectomy may be performed through a medium sized arteriotomy and closed with a vein patch, to which an internal mammary artery (IMA) or saphenous vein graft is constructed. More diffuse disease, or the breaking of an endarterectomy specimen, may require a direct vision total endarterectomy of the entire length of the left anterior descending coronary artery (LAD), which is then closed by a long vein patch. The IMA is not usually grafted to such an extensive reconstruction. There has not been an increase in perioperative risk from LAD endarterectomy when compared to patients undergoing coronary artery bypass grafting without endarterectomy. (J Card Surg 1994;9:89–96)

Notes: A technique is described that provides early reperfusion of acutely ischemic myocardium during the construction of saphenous vein bypass grafts to the coronary arteries. Selective vein graft perfusion provides early and appropriate cooling of the most ischemic zones identified by either electrocardiographic changes or intramyocardial temperature probes and allows warm blood reperfusion during construction of proximal anastomoses. The technique may be applicable to patients who present with acute ischemia and evolving infarction, failed angioplasty, or left main coronary artery stenosis.

Notes: Abstract From November 1989 to December 1994, we performed 2264 bypass procedures. Data were collected prospectively. The population was divided into three subgroups: group 1 = single internal mammary artery (IMA) ± veins (n = 1584); group 2 = veins only (n = 503); and group 3 = two or more arterial conduits ± veins (n = 177). Patients who received only saphenous vein conduits (group 2) were significantly older (66.7 ± 8.9 years) than either group 1 (60.3 ± 8.3 years) or group 3 (51.6 ± 9.2 years). Furthermore, this cohort group had the highest percentage of females (28.6%), urgent cases (43.5%), preoperative myocardial infarction (MI) (18.5%), and redo surgery (5.4%). In contrast, patients who received two or more arterial conduits were 94.9% male, and had the lowest incidence of urgent cases (18.1%) and redo surgery (0.5%). Mortality was 1.4% in group 1 and 3.2% in group 2; there were no deaths in group 3. Furthermore, group 2 patients had the highest incidence of perioperative MI (6.6%), low output syndrome (22.1%), intra-aortic balloon pump (IABP) assist (6.2%), and stroke (2.7%). By multivariate logistic regression analysis (odds ratio in parentheses), redo surgery (7.92), preoperative IABP (5.53), poor LV function (4.01), renal impairment (3.94), and advanced age (2.12) were all predictors of operative mortality. When mortality and morbidity (death, infarction, low output syndrome, IABP assist) were combined, regression analysis revealed that in addition to the above variables, female gender and cold cardioplegia were also independent predictors of combined mortality and morbidity. Resource utilization was determined for the three patient groups. There was concern that the increased technical demands of multiple arterial grafting along with longer periods of aortic occlusion and pump times may lead to increased complications and prolonged hospital stay. However, we found that group 3 had the lowest ventilation time, intensive care unit stay, and hospital stay. The results no doubt were influenced by case selection. Whether or not this approach to revascularization will increase long-term survival and freedom from reoperation will require further study.

Notes: Abstract  A prospective randomized trial was conducted to evaluate the early efficacy and safety of the Gortex surgical membrane. Three hundred two patients (265 males, 37 females) undergoing isolated coronary bypass surgery were randomized to receive a Gortex membrane (GM = 138) or have the pericardium left open (complication [C] = 164). The groups did not differ in age, gender, urgency of procedure, length of procedure, or use of arterial grafts. Two deaths occurred in each group giving an overall mortality of 1.3%. Fifty-three (17%) patients experienced some complication (C = 34, 21%), GM = 19 (14%). Although the combined complication rate was higher in the control group, this was not statistically significant (X2 = 2.51, p = 0.11). Postoperative is-chemic events (C = 8, GM = 4) observed between the groups were not significant (X2 = 0.05, p = 0.8), and no statistically significant difference was observed between the incidences of infections (C = 7, GM = 5) or mediastinal complications (C = 3, GM = 3). The Gortex surgical membrane can be used safely without increasing the risk of infection or mediastinal complications. The incidence of recurrent myocardial ischemia, a possible indicator of graft compression, was not higher following membrane implantation. Efficacy at injury prevention will need to be determined by a longitudinal follow-up study presently underway.

Notes: We report our initial experience from April 1992 to November 1993 with a stentless porcine valve (Toronto SPVTM Valve, St. Jude Medical) for aortic valve replacement (AVR) in 21 consecutive patients and compare this group to a matched cohort that underwent AVR with a Hancock II (Medtronic) bloprosthesis. There were no hospital deaths in either group. Postoperative hospitalization was 5.5 ± 0.8 versus 7.0 ± 2.3 days (p = 0.004). Aortic cross-clamp time was 114.5 ± 15.7 min In the SPV group and 96.0 ± 25.0 min in the Hancock II group (p = 0.003). Complications in the SPV group were: one patient suffered perioperative infarction, one patient required late reoperation for left main stenosis, and one patient died suddenly following femoral thrombectomy at another center. Complications in the Hancock II group included: one patient with postoperative low output syndrome, and two late deaths (one from an aortic dissection and the other from chronic liver disease secondary to alcohol abuse). Comparison data indicate that the average size valve implanted in the SPV group was higher than in the Hancock II group (26.3 ± 1.9 vs 24.0 ± 1.9, p = 0.001). In the SPV group, 16 patients had 0 or trivial regurgitation and 1+ regurgitation was seen in 5 patients; regurgitation did not change over a 12-month follow-up. We observed a decrease in gradients over time (p 〈 0.01). Our results are compatible with a hypothesis that the ventricle undergoes remodeling over time, once the obstruction is relieved. We think the stentiess design is an important feature that allows this to occur. Furthermore, this design allows for the implantation of a larger size valve for the same body size, as well as for decreased shear forces during diastole, with accompanying better hemodynamics, and potential improvement in longevity. These results indicate that the SPV valve has excellent hemodynamic characteristics that do not appear to change over a short follow-up period.

Notes: Patients with postinfarction angina undergoing surgery for unstable angina face an increased risk of operative mortality. Between January 1982 and December 1987, clinical, angiographic, and operative data was collected prospectively in 588 unstable patients with a prior myocardial infarction within 30 days of surgery (MI) and 5951 unstable patients without preoperative damage (NONMI). MI patients were characterized as being older (age ± 70 years: MI, 19.7%; NONMI, 11.6%; p 〉 0.001) and having more left ventricular dysfunction (left ventricular ejection fraction 〉 40%: MI, 34.8%; NONMI, 26.4%; p 〉 0.001). Semi-elective surgery was performed in 82.0% of NONMI patients while 76.9% of MI patients underwent urgent surgery. Operative mortality was increased in MI patients (MI, 11.1%; NONMI, 4.0%; p 〉 0.001) which was related to the extent of preoperative MI (non-Q wave, 8.3%; Q wave, 17.5%; p 〉 0.001). Stepwise logistic regression analysis identified preoperative MI as an independent risk variable of operative mortality for unstable angina. Separate multivariate analyses were performed to identify the independent predictors for MI and NONMI patients. The multivariate predictors of operative death for MI patients were left ventricular dysfunction, reoperative coronary surgery, nonuse of the internal mammary, age, transmural MI (relative risk 2.11 vs non-Q wave infarction) and left main stenosis. For NONMI patients, the independent variables were urgent operation, left ventricular dysfunction, reoperation, female gender, left main stenosis, and age. The results of this study indicate that recent preoperative MI adversely influences the surgical results in patients with unstable angina. Alternative treatment strategies are warranted for high risk patients, particularly those with transmural MIs and impaired ventricular function.

Notes: Temporary wires are routinely sutured to atrial and/or ventricular epimyocardium after open heart surgery. Despite the common problems of poor sensing or capture, dislodgement or retention, no criteria exists for proper placement or removal. This report describes clinical complications due to: failure of ventricular sensing, failure of ventricular capture, bleeding from right ventricular laceration with tamponade, avulsion of a side branch from a saphenous vein coronary bypass graft, and perforation of the superior epigastric artery. Appropriate placement of temporary wires for optimum function requires 2-cm electrode separation, application into both atrium and ventricle with a gentle redundant loop to exit near the midline, avoiding both coronary arteries and coronary artery bypass grafts. Gentle traction for removal is recommended on the day prior to discharge, especially for patients on antiplatelet or anticoagulant therapy.

Notes: There is renewed interest in the use of the radial artery as a conduit for coronary artery bypass. Fifty patients underwent bypass surgery using the radial artery in addition to other conduits between November 24, 1992 and November 8, 1994 at our institution. The mean age was 54.4 ± 9.1 years (mean ± SD) and 47 of the patients were male. There were 3.6 ± 0.9 anastomoses per patient, of which 2.2 ± 0.4 were arterial anastomoses. The most common target vessel for the radial artery has been the obtuse marginal (58.8%), with the aorta as the usual site for proximal anastomosis (80.4%). There have been no ischemic hand complications and no radial nerve deficits. There have been no early or late deaths and no myocardial ischemic complications related to the use of the radial artery. We present the techniques used at our institution for the use of the radial artery as a conduit for coronary artery bypass.