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: Abstract The excellent hemodynamics of stentless valves have been observed by numerous investigators. With the recent release of the Toronto SPV (stentless porcine valve) and the Medtronic Freestyle stentless valves in North America, it is appropriate to now compare the clinical and hemodynamic performance of these devices. We analyzed the results of 995 patients who underwent aortic valve replacement (AVR) with either of the two valves; in all cases a subcoronary implant technique was used. There were important differences in the preoperative characteristics for the two groups: Medtronic Freestyle patients were notably older than the Toronto SPV patients (70.7 ± 8.6 vs 61.8 ± 11.1 years, p 〈 0.001) and were markedly more symptomatic (p 〈 0.0001). In the Toronto SPV group, most patients had New York Heart Association (NYHA) Class II (41.5%) or Class III (44.7%) symptoms preoperatively, while in the Freestyle group, 61.5% were in Class III and 12.5% were in Class IV. There were no notable differences in mortality or morbidity for the two groups. Both devices demonstrated a meaningful decrease in mean gradient and a corresponding increase in effective orifice area (EOA). Furthermore, the indexed EOA (EOA/body surface area [BSA]) was 〉 1cm2/m2 for all valves indicating there was no patient-prosthetic mismatch. There was a meaningful decrease in left ventricular (LV) mass as well as LV mass index (LVMI) for both devices up to 3 years postoperatively. Our data indicate that there were no differences in clinical outcome or hemodynamic performance of these two valves. Both devices offer excellent results with normalization of LV function.

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.

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 Background: This study is comprised of 3493 consecutive patients who underwent open heart surgery at our institution. Data on all patients were collected prospectively. Methods: In 45 patients (Group P) (1.3%), a permanent pacemaker (PP) was inserted postoperatively. For the purpose of the study, these patients were compared to 3448 patients (Group NP) who did not require insertion of a PP after surgery. Mean follow-up was 33 months (range 1.5 to 66). Results: We found Group P patients were older (64.8 ± 11.0 vs 61.0 ± 11.0 years, p 〈 0.05), had a higher proportion of elderly (〉 70 years) (36% vs 19%, p = 0.01), and of female patients (48.8% vs 22.7%, p 〈 0.001) compared to Group NP. Group P also had a higher incidence of preoperative rhythm abnormalities (26.6% vs 5.7%, p 〈 0.0001), redo surgery (13.3% vs 4.6%, p = 0.02), aortic valve surgery (48.8% vs 10.8%, p 〈 0.001), and tricuspid valve surgery (repair 3, replacement 1) (8.8% vs 0.5%, p 〈 0.001), in addition to a higher proportion of patients in whom cold (vs warm) blood cardioplegia was used (68.8% vs 52.3%, p = 0.03). Indication for postoperative PP was sick sinus syndrome (SSS) in nine patients; atrial fibrillation in eight patients; atrioventricular block (AVB) in 27 patients; and combined AVB/SSS in 1 patient. There were no operative deaths in Group P. Necessity for PP after heart surgery had a significant impact on resource utilization resulting in prolonged ventilation (3.1 ± 7.5 vs 1.4 ± 3.3 days, p 〈 0.01), intensive care unit (5.1 ± 10.2 vs 2.5 ± 4.0 days, p 〈 0.01), and postoperative hospital stay (18.0 ± 13.4 vs 8.1 ± 9.4 days, p 〈 0.01). Conclusions: By multivariate logistic regression (odds ratio and p value in parentheses), aortic valve surgery (8.23, p = 0.001), the absence of preoperative sinus rhythm (5.60, p = 0.001), postoperative myocardial infarction (3.46, p = 0.024), and female gender (2.52, p = 0.003), were found to be independent predictors for PP requirement post surgery.

Notes: Background: The incidence of coronary artery bypass surgery has been increasing annually with increasing pressure on the health care system. Fast track has been proposed as a means to increase efficiency and volume, without an increase in hospital re-sources. To date this approach has not been critically assessed in Canada. Methods: We examined 617 consecutive patients undergoing isolated CABG surgery. The patients were divided into (1) fast track (FT) recovery (n = 219), without admission to an ICU, and (2) nonfast track (NFT) recovery (n = 398) with direct admission to the ICU. There were no differances in age, gender, timing of surgery, left main stenosis, preoperative myocardial infarction, renal failure, diabetes, peripheral vascular disease, or in the incidence of chronic obstructive pulmonary disease between the two groups. The NFT group had a higher proportion of patients with NYHA Class III/IV symptoms preoperatively (65.7% vs. 57.3%, p = 0.048), in patients with an ejection fraction 〈 40% (42.5% vs. 30.6%, p = 0.004), or in the number of individuals with an IABP inserted before surgery (13 vs. 1, p 〈 0.001). Results: In the FT group the average period of aortic occlusion (40.7 ± 15.2 min vs. 71.8 ± 26.5 min, p 〈 0.001) and perfusion time (67.8 ± 24.5 min vs. 117.5 ± 40.2 min, p 〈 0.001) were significantly less than in the NFT group. The number of grafts per patient was 3.3 ± 1.0 vs. 3.2 ± 1.0, respectively (p = 0.38). Operative mortality was 0.9% in the FT group and 1.3% in the NFT group (p = 1.0). Significant differences were seen in the proportion of patients that suffered from postoperative ventilatory failure (3.2% in FT vs. 12.1% in NFT, p 〈 0.001), and the proportion of patients that suffered any postoperative complication was significantly higher in the NFT group (21.4%) than in the FT group (9.1%, p 〈 0.001). The differences in postoporative complications resulted in a shorter length of stay (LOS) in FT patients (5.6 ± 4.1 days vs. 9.7 ± 9.4 days NFT, p 〈 0.001). Only 4.1% of patients that entered the FT group failed and required admission to the ICU. Multivariate stepwise logistic regression analysis identified non-fast track recovery as an independent predictor of morbidity in CABG surgery patients. Conclusions: The data indicate it is possible to perform isolated CABG surgery, in a large proportion of the population, without the need for admission to an ICU for postoperative care.