Implementation of the aortic no-touch technique to reduce stroke after off-pump coronary surgery.

OBJECTIVES: Despite substantial scientific effort, the relationship between stroke after coronary artery bypass grafting and the use of the aortic no-touch off-pump technique (anOPCAB) remains incompletely understood. The present study aimed to define the effect of anOPCAB on the occurrence and time point of stroke. METHODS: A total cohort of 15,042 consecutive patients underwent surgical myocardial revascularization at a single institution. After establishing anOPCAB as routine procedure, 4695 patients received surgery by 18 different surgeons using the anaortic approach. After the exclusion of all patients with cardiogenic shock and "side-clamp" off-pump coronary artery bypass grafting, 13,279 patients (4485 with anOPCAB) were included in the study. Perioperative strokes were classified as strokes occurring during the hospital stay, with early strokes observed immediately after emergence from anesthesia (vs delayed strokes). RESULTS: The anOPCAB technique reduced the postoperative stroke rate to 0.49% versus 1.31% in on-pump patients (P < .0001). The overall stroke rate after adoption of anOPCAB (0.64%) decreased compared with before its adoption (1.40%; P < .0001). With anOPCAB, the risk of early strokes virtually disappeared to 4 of 4485 patients (0.09%; 95% confidence interval, 0.00-0.18% vs 0.83% in on-pump patients; P < .0001), whereas the incidence of delayed strokes was not affected (0.40% vs 0.48%; P = .5181). The key results were confirmed after adjustment using propensity score-based analyses. CONCLUSIONS: The anOPCAB technique with avoidance of any aortic manipulation is an effective tool to minimize the risk of early strokes during coronary artery bypass grafting, and thus, should be considered as a routine approach. In contrast, additional preventive strategies against delayed strokes remain to be elaborated.

Stentless Bioprostheses for Aortic Valve Replacement in Octogenarians: The Influence of Coronary Artery Disease.

BACKGROUND: We sought to determine the long-term results of stentless biological heart valve replacement in octogenarians to find out whether coronary artery disease or the coronary artery bypass grafting (CABG) procedure itself influences survival in these aged patients. METHODS: From 4,012 patients undergoing aortic valve replacement (AVR) with a stentless prosthesis (Freestyle, Medtronic) at a single center, 721 patients were older than 80 years. They had a mean age of 83 ± 2 (2,320 patient years), the male/female ratio was 42:58, NYHA (New York Heart Association) class I and II was prevalent in 22.8%, preoperative atrial fibrillation (AF) in 20.6%, coronary artery disease in 56.1%, mitral valve disease in 12.5%, and aortic disease in 3.5%. Follow-up included a total of 11,546 patient years (mean follow-up time: 74 ± 53 months); follow-up mortality data were 96.3% complete. RESULTS: In these aged patients, 30-day mortality in the isolated AVR group (10.3%) was similar to that in the AVR + CABG group (13.4%). Although long-term survival (15 years) in the octogenarian population is low (9% in the AVR group and 6% in the AVR + CABG group), it was not different (p = 0.191) between patients with and without coronary artery disease. The stroke rate and the myocardial infarction rate, respectively, in the AVR + CABG group (0.43%/100 patient years and 0.17%/100 patient years) were only insignificantly higher than that in the isolated AVR group (each 0.01%/100 patient years). The actuarial freedom from reoperation was 99% in both the groups. CONCLUSION: Use of the Freestyle stentless valve prosthesis for AVR is feasible also in octogenarians. The existence of coronary artery disease leads to concomitant bypass surgery, but not a higher level of perioperative or long-term mortality.

Current indications for stentless aortic bioprostheses.

The best aortic prostheses have been debated for decades. The introduction of stentless aortic bioprostheses was aimed at improving hemodynamics and potentially the durability of aortic bioprostheses. Despite the good short- and long-term outcomes after implantation of stentless aortic bioprostheses, their use remains limited owing to the technically demanding implantation techniques. Nevertheless, stentless aortic bioprostheses might be of special benefit in certain indications, where they could be a valuable addition to the surgical armamentarium.

Freestyle stentless bioprosthesis for aortic valve therapy: 17-year clinical results.

BACKGROUND: Aortic valve replacement with stentless bioprostheses has been shown to produce lower aortic gradients than stented bioprostheses, thus facilitating left ventricular mass regression and preventing heart failure. We sought to determine the long-term results of stentless biological aortic valve replacement over a 17-year follow-up. METHODS: Between 1996 and 2012, 2551 patients underwent isolated aortic valve replacement with a stentless prosthesis (Medtronic Freestyle) at a single center. The mean patient age was 72 ± 10 years, 55% were male, 24.1% were in New York Heart Association class I and II, 9.6% had undergone previous surgery, 18.1% had coronary artery disease, and 23.1% had diabetes. For the long-term follow-up, patients were contacted in writing and by telephone; follow-up was 96.3% complete, resulting in 11,546 patient-years. RESULTS: At 30 days, mortality (5.4%), renal failure (3.9%), myocardial infarction (0.7%), and stroke (1.4%) rates were acceptable. During long-term follow-up of 1-17 years, the bleeding rate (2.9%) was higher than the thromboembolic event rate (0.7%) despite 18.1% of patients being on oral anticoagulants. New pacemaker implantation (4.5%; 0.87 events/100 patient-years), neurological disorders (5%; 0.52 events/100 patient-years), valve insufficiency (0.7%; 0.16 events/100 patient-years), paravalvular leakage (0.4%; 0.09 events/100 patient-years) and reoperation due to valvular complications (0.7%; 0.38 events/100 patient-years) were rare. Long-term survival was 41.8% ± 1.6 after 10 years, 21.3% ± 2.3 after 15 years, and 12.1% ± 3.9 after 17 years. CONCLUSION: Long-term results after aortic valve replacement with stentless biological prostheses compare favorably with those obtained with stented bioprostheses.

Are aortic valve reoperations after primary replacement with stentless heart valve prostheses more demanding than after stented biological prostheses?

OBJECTIVE: Reoperations after aortic valve replacement (AVR) with stentless valve prostheses are believed to be surgically more difficult than after stented prostheses. METHODS: Between January 1996 and December 2006, 1,340 of 3,785 patients with AVR in a single institution received a stentless valve prosthesis in aortic position (Medtronic Freestyle, Medtronic GmbH, Meerbusch, Germany). Reoperations after stentless AVR occurred in 27 patients (2.0%). Twenty-four of these patients were compared with another 24 patients having redo surgery after a primary stented bioprosthesis after carrying out propensity score matching. RESULTS: After matching, stentless valve redo patients had a similar preoperative risk profile regarding EuroSCORE (stentless 10 ± 3 points/stented 11 ± 3 points; p = 0.37), preoperative active endocarditis (stentless 37.5%/stented 16.7%; p = 0.081), and amount of concomitant procedures (stentless 37.5%/stented 16.7%; p = 0.222). Thirty-day mortality after reoperation was 20.8% (5 patients) in the stentless and 4.2% (1 patient) in the stented group (p = 0.081), and reintubation rate was 16.7% in the stentless and 0% in the stented group (p = 0.037). Aortic clamping time (stentless 90 ± 25 min/stented 86 ± 34 min; p = 0.208) and extracorporeal circulation time (stentless 151 ± 59 min/stented 132 ± 52 min; p = 0.55) were similar in both groups. CONCLUSION: Our data do not show that the technical difficulty of reoperations after stentless AVR is higher than that of reoperations after stented AVR. The clinically visible, but not statistically significant, higher early mortality rate of our stentless group is mainly due to more active valve prosthesis endocarditis cases and a higher amount of concomitant procedures.

The history of the management of sternal osteomyelitis and mediastinitis - from Hippocrates until today.

Even during the time of Hippocrates, Galen and their colleagues recognized mediastinal affections. However, they were not considered with the surgical treatment. First progress in the treatment options of this severe disease, still denoted as 'terra incognita', over to today's gold standard are pictured. The mediastinitis-registry which was founded by the German Society for Thoracic and Cardiovascular Surgery (DGTHG) in 2011 and the recent establishment of the study group to adopt a guideline 'diagnosis and therapy of postoperative mediastinitis/sternal osteomyelitis following cardiac surgery' are attempts to a standardization of the treatment. Substantial advancement in the treatment of postoperative mediastinitis could be achieved in the past. The mortality dropped as low as less than 10%. With these implementations more benefit for the patients' outcome can be expected.

Midterm outcome after aortic root replacement with stentless porcine bioprostheses.

OBJECTIVE: Midterm clinical outcome was evaluated after aortic root replacement with Freestyle® stentless aortic root bioprostheses. METHODS: Between April 1996 and December 2007, 301 patients underwent aortic valve replacement with stentless Medtronic Freestyle® bioprostheses in full-root technique at a single center. Concomitant coronary artery bypass grafting (CABG) was required in 96 patients (32%). In 94 patients (31%), the ascending aorta was replaced. The mean age was 71.6 ± 9.1 (range: 36-89) years. Follow-up was closed in October 2008, 99% complete and encompassed 916 patient-years. RESULTS: Overall mortality within 30 days was 5%. A total of 62 patients died during the follow-up period. Overall survival at 5 and 9 years was 74 ± 4% and 53 ± 6%, respectively. Re-operations were required in three patients: in one patient due to structural valve deterioration, and in two patients due to prosthetic valve endocarditis. Non-structural dysfunctions were not observed. In eight patients, prosthetic valve endocarditis occurred, in most of them (N = 6) during the first year after surgery. Rate of freedom from re-operation, structural valve deterioration, prosthetic valve endocarditis, thrombo-embolic and major bleeding events at 9 years was 94 ± 6%, 94 ± 6%, 94 ± 3%, 87 ± 5%, and 95 ± 2%, respectively. The linearized rates of late adverse events in percent per patient-year were 0.35, 0.12, 0.83, 1.7, and 0.7, respectively, for re-operation, structural valve deterioration, prosthetic valve endocarditis, thrombo-embolic and major bleeding events. A little less than a quarter (22%) of the patients required anticoagulation therapy. CONCLUSIONS: Aortic root replacement with the stentless Freestyle® bioprosthesis provided a respectable short-term mortality, optimal valve durability and acceptable rates of valve-related complications within 9 years.

Short term outcomes of total arterial coronary revascularization in patients above 65 years: a propensity score analysis.

BACKGROUND: Despite the advantages of bilateral mammary coronary revascularization, many surgeons are still restricting this technique to the young patients. The objective of this study is to demonstrate the safety and potential advantages of bilateral mammary coronary revascularization in patients older than 65 years. METHODS: Group I included 415 patients older than 65 years with exclusively bilateral mammary revascularization. Using a propensity score we selected 389 patients (group II) in whom coronary bypass operations were performed using the left internal mammary artery and the great saphenous vein. RESULTS: The incidence of postoperative stroke was higher in group II (1.5% vs. 0%, P = 0.0111). The amount of postoperative blood loss was higher in group I (908 +/- 757 ml vs. 800 +/- 713 ml, P = 0.0405). There were no other postoperative differences between both groups. CONCLUSION: Bilateral internal mammary artery revascularization can be safely performed in patients older than 65 years. T-graft configuration without aortic anastomosis is particularly beneficial in this age group since it avoids aortic manipulation, which is an important risk factor for postoperative stroke.

Aortic valve replacement in octogenarians: identification of high-risk patients.

OBJECTIVE: This study identifies high-risk octogenarians for surgical aortic valve replacement (AVR) because with the current advances in transcatheter valve therapy, a definition of patient selection criteria is essential. METHODS: Between 1996 and 2006, 493 consecutive octogenarians with symptomatic aortic stenosis underwent AVR with and without (51%) concomitant coronary artery bypass grafting (CABG). To identify high-risk patient groups, risk factors of 6-month mortality were determined using multivariable logistic regression. RESULTS: The 30-day mortality rate was 8.4% and it increased up to 15.2% until 6 months after AVR. Independent risk factors of 6-month mortality were patients older than 84 years (odds ratio (OR): 2.2 (1.29-3.61)), left ventricular ejection fraction <60% (OR: 2.5 (1.35-4.61)), body mass index (BMI) <24 (OR: 2.0 (1.22-3.36)), creatinine (OR: 1.6 (1.04-2.53)) and blood glucose (OR: 1.01 (1.001-1.009)). High-risk groups were patients older than 84 years with an ejection fraction <60% (6-month mortality 28%) and patients younger than 84 years with an ejection fraction <60% and a BMI <24 (6-month mortality 23.2%). These high-risk groups comprised 37% of the patient population. After isolated AVR, the 30-day mortality and survival at 1 and 5 years was 11.6%, 69% and 35% in this high-risk group, respectively. In octogenarians with an STS score >10 and an EuroScore >20, the 30-day mortality and survival at 1 year was 10.5% and 80%, 11.6% and 77%, respectively. CONCLUSIONS: In most octogenarians, AVR is a safe and beneficial procedure. In high-risk octogenarians, identified by STS score >10, EuroScore >20 and by simple three risk factors (age >84 years, ejection fraction <60% and BMI <24), the mortality after surgical AVR was no different from the currently reported outcome after transcatheter AVI.

Impact of gender on outcome after coronary artery bypass surgery.

Following recent studies concerning the increased risk of coronary artery bypass surgery for women, the impact of sex is still a controversial issue. Between 1996 and 2006, 9,527 men and 3,079 women underwent isolated coronary artery bypass in our institute. To adjust for dissimilarities in preoperative risk profiles, propensity score-based matching was applied. Before adjustment, clinical outcomes in terms of operative mortality, arrhythmias, intensive care unit stay, and maximum creatine kinase-MB levels were significantly different for men and women. After balancing the preoperative characteristics, including height, no significant differences in clinical outcomes were observed. However, there was decreased use of internal mammary artery, less total arterial revascularization, and increasing creatine kinase-MB levels with decreasing height. This study supports the theory that female sex per se does not increase operative risk, but shorter height, which is more common in women, affects the outcome, probably due to technical difficulties in shorter patients with smaller internal mammary arteries and coronary vessels. Thus women may especially benefit from sequential arterial grafting.

The concept of negative pressure wound therapy (NPWT) after poststernotomy mediastinitis--a single center experience with 54 patients.

Deep sternal infections, also known as poststernotomy mediastinitis, are a rare but often fatal complication in cardiac surgery. They are a cause of increased morbidity and mortality and have a significant socioeconomic aspect concerning the health system. Negative pressure wound therapy (NPWT) followed by muscular pectoralis plasty is a quite new technique for the treatment of mediastinitis after sternotomy. Although it could be demonstrated that this technique is at least as safe and reliable as other techniques for the therapy of deep sternal infections, complications are not absent. We report about our experiences and complications using this therapy in a set of 54 patients out of 3668 patients undergoing cardiac surgery in our institution between January 2005 and April 2007.

The Freestyle stentless bioprosthesis in more than 1000 patients: a single-center experience over 10 years.

BACKGROUND AND AIM: Early and mid-term clinical outcomes after aortic valve replacement (AVR) with stentless bioprostheses in a large cohort of patients are presented. METHODS: Between April 1996 and November 2005, 1014 patients underwent AVR with the stentless Medtronic Freestyle bioprosthesis, with 168 using the full-root technique. The mean age was 73+/-3 (range: 20 to 90) years. Follow-up included 2953 patient-years and was 95% complete for adverse events. RESULTS: Operative mortality was 3.4% (N=34). Overall survival was 46+/-9% at nine years and similar to age- and gender-matched German general population. Freedom from prosthetic valve endocarditis, major bleeding, neurological events, and reoperation after nine years was 97+/-6%, 92+/-7%, 70+/-16%, and 92+/-9%, respectively. Freedom from structural valve deterioration was 97+/-5% at 9 years. During the learning phase, mean transprosthetic gradients of 23.5+/-3.0 mmHg and 24.8+/-3.1 mmHg were observed for valve sizes 21 and 23 mm, respectively, 10 days after subcoronary implantation in 1997, which could be lowered to 16+/-2.1 mmHg and 14.9+/-0.9 mmHg in 2005, respectively, with increasing experience of the surgeons. During the follow-up period, mean gradients dropped on average by 15 mmHg in patients presenting higher gradients at discharge. CONCLUSIONS: The Freestyle stentless bioprosthesis showed encouraging midterm durability with low rates of valve-related morbidity, and can be safely implanted without increased operative risk even during the learning phase. Special training of the surgeons is recommended to achieve optimal hemodynamic performance.

Impact of valve prosthesis-patient mismatch estimated by echocardiographic-determined effective orifice area on long-term outcome after aortic valve replacement.

BACKGROUND: The impact of valve prosthesis-patient mismatch on long-term outcome after aortic valve replacement estimated by various variables such as projected indexed effective orifice area and internal geometric orifice area obtained from in vivo or in vitro published data is still controversial. METHODS: The effective orifice area was measured by echocardiography in 533 patients. The mean age of the patients was 71 +/- 9 years; mean follow-up time was 4.7 +/- 2.2 years. The impact of severe (indexed effective orifice area

Ten-year experience with stentless aortic valves: full-root versus subcoronary implantation.

BACKGROUND: We compared the midterm outcome after aortic valve replacement with the Freestyle stentless bioprosthesis for the full-root or subcoronary implantation technique, while adjusting for patient and disease characteristics by a propensity score. METHODS: Between 1996 and 2005, 1,014 patients underwent aortic valve replacement with the stentless Medtronic Freestyle bioprosthesis, 168 using full-root technique. Based on a saturated propensity score, 148 matched pairs were created. Mean age of the 296 patients was 73 +/- 3 years. Mean follow-up time was 32 +/- 30 months (maximum, 116 months). RESULTS: Operative mortality was 4.7% and 2.7% (p = 0.36) in the full-root and subcoronary groups, respectively. Freedom from reoperation, prosthetic valve endocarditis, major bleeding, and thromboembolism after 9 years was 98% +/- 1% and 90% +/- 7% (p = 0.38), 95% +/- 3% and 92% +/- 7% (p = 0.76), 72% +/- 21% and 98% +/- 2% (p = 0.12), and 75% +/- 8% and 84% +/- 7% (p = 0.28), for full-root and subcoronary groups, respectively. Survival rates after 9 years were 34% +/- 24% and 33% +/- 11% (p = 0.46), for the full-root and subcoronary groups, respectively. Patients in the full-root group received larger valve sizes (p = 0.03), and the mean transprosthetic gradients at discharge were significantly lower for each valve size. Nevertheless, during follow-up, peak gradients decreased to a greater extent in patients presenting high peak gradients (>36 mm Hg) at discharge. CONCLUSIONS: As risk-adjusted comparison of both implantation techniques did not reveal any differences regarding operative and midterm outcomes, full-root replacement can be liberally performed in patients with small aortic roots, annuloaortic ectasia, or requiring replacement of ascending aorta.

Effect of surgeon on transprosthetic gradients after aortic valve replacement with Freestyle stentless bioprosthesis and its consequences: a follow-up study in 587 patients.

BACKGROUND: The implantation of stentless valves is technically demanding and the outcome may depend on the performance of surgeons. We studied systematically the role of surgeons and other possible determinants for mid-term survival, postoperative gradients and Quality of Life (QoL) after aortic valve replacement (AVR) with Freestyle stentless bioprostheses. METHODS: Between 1996 and 2003, 587 patients (mean 75 years) underwent AVR with stentless Medtronic Freestyle(R) bioprostheses. Follow-up was 99% complete. Determinants of morbidity, mortality, survival time and QoL were evaluated by multiple, time-related, regression analysis. Risk models were built for all sections of the Nottingham Health Profile (NHP): energy, pain, emotional reaction, sleep, social isolation and physical mobility RESULTS: Actuarial freedom from aortic valve re-operation, structural valve deterioration, non-structural valve dysfunction, prosthetic valve endocarditis and thromboembolic events at 6 years were 95.9 +/- 2.1%, 100%, 98.7 +/- 0.5%, 97.0 +/- 1.5%, 79.6 +/- 4.3%, respectively. The actuarial freedom from bleeding events at 6 years was 93.1 +/- 1.9%. Estimated survival at 6 years was similar to the age-matched German population (61.4 +/- 3.8 %). Predictors of survival time were: diabetes mellitus, atrial fibrillation, peripheral vascular disease, renal dysfunction, female gender > 80 years and patients < 165 cm with BMI < 24. Predictive models showed characteristic profiles and good discriminative powers (c-indexes > 0.7) for each of the 6 QoL sections. Early transvalvular gradients were identified as independent risk factors for impaired physical mobility (c-index 0.77, p < 0.002). A saturated propensity score identified besides patient related factors (e.g. preoperative gradients, ejection fraction, haematological factors) indexed geometric orifice area, subcoronary implantation technique and individual surgeons as predictors of high gradients. CONCLUSION: In addition to the valve size (in relation to body size), subcoronary technique (versus total root) and various patient-related factors the risk of elevated gradients after stentless valve implantation depends, considerably on the individual surgeon. Although there was no effect on survival time and most aspects of QoL, higher postoperative transvalvular gradients affect physical mobility after AVR.

Current determinants of 30-day and 3-month mortality in over 2000 aortic valve replacements: Impact of routine laboratory parameters.

OBJECTIVE: Haematological and biochemical measurements are performed routinely before surgery to exclude organ malfunction and blood cell and coagulation abnormalities. We aimed to test routinely obtained laboratory data as factors predicting operative risk. METHODS: Between 1996 and 2003, 2198 patients underwent aortic valve replacement (AVR) (908 of them with concomitant CABG) in our institute. The mean age of the study population was 69+/-11 years (range 13-91, 43% female). Clinical and laboratory parameters based on the consolidated data mart set were evaluated by multiple logistic regression analysis. RESULTS: The overall operative mortality (within 30 days) was 3.8% and the mortality after 3 months was 5.9%. In addition to clinical characteristics, the following laboratory values were identified as independent predictors of 30-day mortality: fasting blood glucose, antithrombine III, partial thromboplastine time and creatinine kinase. As independent predictors of 3-month mortality, the following laboratory values were indentified: fasting blood glucose, serum creatinine, antithrombine III, partial thromboplastine time, lactate dehydrogenase, sodium concentration and serum proteins. The discriminative power of the models increased if laboratory parameters were included in addition to preoperative clinical characteristics (from 0.75 to 0.79 and from 0.75 to 0.78 for 30-day and 3-month mortality, respectively). The discriminative power using the logistic EuroScore was lower (0.71 and 0.7, for 30-day and 3-month mortality, respectively). CONCLUSIONS: Laboratory parameters as objective markers for organ function and nutritional status are useful data for the prediction of 30-day and 3-month mortality after aortic valve replacement. Using modern methods of information technology, these valuable data which are stored electronically in most hospitals, can be used efficiently for research and quality control.

The stentless freestyle bioprosthesis: impact of age over 80 years on quality of life, perioperative, and mid-term outcome.

BACKGROUND: The steadily increasing life expectancy of the population in the Western World, together with the progress in noninvasive diagnostic methods and operating techniques lead to an increase in aortic valve surgery in elderly people. AIM OF THE STUDY: Is there an increased risk of adverse perioperative and mid-term outcome for octogenarians and do they benefit from aortic valve replacement (AVR) with stentless bioprostheses? METHODS: Between 1996 and 2002, 503 patients older than 60 years underwent AVR with a stentless Freestyle bioprosthesis. Seventy-six of them were older than 80 years. The risk of operative mortality, perioperative complications, valve-related morbidity for octogenarians was determined by multivariate logistic regression. RESULTS: In general, risk-adjusted analyses did not reveal an increased risk of operative mortality (p = 0.4), postoperative atrial fibrillation (p = 0.2), prolonged ventilation (p = 0.5), prolonged stay in the intensive care unit (p = 0.3), or mid-term valve-related morbidity as prosthetic valve endocarditis (p = 0.2), reoperation (p = 0.4), bleeding events (p = 0.1), and stroke (p = 0.8) for octogenarians. Continuously increasing age was an independent risk factor for postoperative neurological complications (OR = 1.8 per 10 years, p = 0.04). Quality of life was equal to or better than the general population of the same age. Median survival time of octogenarians was 5.2 +/- 0.5 years. CONCLUSIONS: Except for postoperative neurological complications, octogenarians receiving stentless bioprostheses had no increased risk of adverse perioperative and mid-term outcome in comparison to younger patients. As quality of life and life expectancy after AVR with stentless valves were equal to the general population, AVR with stentless bioprostheses should not be withheld from octogenarians.

Body mass index: a risk factor for 30-day or six-month mortality in patients undergoing aortic valve replacement?

BACKGROUND AND AIM OF THE STUDY: In recent studies, the impact of a low or high body mass index (BMI) on outcome after cardiac surgery has been the subject of controversy. A retrospective study was conducted to determine the influence of BMI on 30-day and six-month mortality after aortic valve replacement (AVR). METHODS: A multivariable logistic regression was performed on data from 1,241 consecutive patients (mean age 69 +/- 11 years) who underwent AVR either with (n = 514; 41%) or without coronary artery bypass grafting CABG between 2000 and 2003. A wide spectrum of periprocedural variables was collected, including laboratory data as markers for nutritional status and comorbidity. Patients were followed up for six months after AVR (99% complete). RESULTS: Mortality rates after 30 days and after six months were 3.9% (n = 49) and 7.6% (n = 94), respectively. A low BMI was identified as an independent risk factor for 30-day (OR (odds ratio) 0.87; CI (confidence interval) 0.8-0.94) and six-month mortality (OR 0.91; CI 0.86-0.96). The relationship between the logit function and BMI was linear; however, a BMI value of 24 was considered an appropriate cut-off point. Both models containing the BMI linearly or dichotomic were equivalent. As patients with a lower BMI differ in their preoperative risk profile compared to those with a higher BMI, a saturated propensity score estimating the propensity towards having a BMI < 24 was calculated. The propensity score was not significant in the final models for 30-day and six-month mortality (0.24 and 0.73, respectively), and the OR for BMI remained largely unaltered (0.89 and 0.91, respectively). CONCLUSION: A BMI < 24 is predictive of an increased risk of mortality after AVR, independently of malnutrition, advanced heart disease, or valve size. Further studies are required to investigate the role of adipose tissue in extreme situations and chronic disease. It is mandatory to include BMI in outcome studies after AVR.

Intraoperative transit time flow measurement: off-pump versus on-pump coronary artery bypass.

BACKGROUND: Off-pump coronary artery bypass grafting (OPCAB) has attracted increasing attention. Performing the anastomosis off-pump is technically more demanding. The objective of the study is to assess the quality of anastomosis in OPCAB in comparison with conventional on-pump coronary artery bypass grafting using the transit time flow measurement. METHODS: Four hundred forty-five patients operated on using OPCAB technique were included in the study. For each patient in this group a similar patient from the on-pump coronary artery bypass grafting population was selected according to the number of grafts, bypass material, and target coronary arteries. The mean flow and the pulsatile index were measured in every bypass graft in both groups. RESULTS: The average pulsatile index in OPCAB was 2.09 +/- 1.03 (mean flow, 39 +/- 22.63 mL/min), whereas with on-pump coronary artery bypass grafting it was 1.9 +/- 0.98 (mean flow, 44.19 +/- 23.58 mL/min); p = 0.005. Subgroup analysis showed significantly lower mean flows and higher pulsatile index with OPCAB in grafts to the obtuse marginal, diagonal, and right coronary artery, but not to the left anterior descending territory. CONCLUSIONS: The quality of the anastomosis performed using the OPCAB technique might be jeopardized by less accessibility as in the case of lateral and posterior wall coronary arteries. Techniques to optimize the accessibility of the coronary artery like combining sling support with cup stabilizers, together with systematic training, should be strongly considered in OPCAB. Whenever there is good accessibility of the coronary artery as in the case of the left anterior descending, the anastomosis performed under OPCAB has a quality as good as that performed using the conventional technique.