Juergen Ennker

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.

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.

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.

Efficacy and Safety of Very Low-Dose Self-Management of Oral Anticoagulation in Patients With Mechanical Heart Valve Replacement

BACKGROUND Self-management improves oral anticoagulation control. Here we provide data of a preplanned interim analysis of very low-dose early self-controlled anticoagulation. METHODS In a prospective, randomized, multicenter trial, 1,137 patients performed low-dose international normalized ratio (INR) self-management with a target INR range of 1.8. to 2.8 for aortic valve replacement recipients and 2.5 to 3.5 for mitral or double valve replacement recipients for the first six postoperative months. Thereafter, 379 patients continued to achieve the aforementioned INR target range (LOW group), whereas the INR target value was set at 2.0 (range, 1.6 to 2.1) for the remaining patients with aortic valve replacement and 2.3 (range, 2.0 to 2.5) for the remaining patients with mitral valve or double valve replacement. One half of this latter group had to check their INR values once a week (VL1 group) the other half twice a week (VL2 group). Patients were followed up for 24 months. RESULTS Beyond study month six, the incidence of thromboembolic events that required hospital admission was 0.58%, 0.0%, and 0.58% in the LOW, VL1, and VL2 groups, respectively (p = 0.368). The incidence of bleeding events per patient-year was 1.16%, 1.07%, and 0.58% in the LOW, VL1, and VL2 groups, respectively (p = 0.665). Mortality rate did not differ among study groups. CONCLUSIONS Data demonstrate the efficacy and safety of very low-dose INR self-management.

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.

Cerebrovascular Events After Stentless Aortic Valve Replacement During a 9-Year Follow-Up Period

BACKGROUND One major advantage of biologic aortic valve prostheses is their low thrombogenicity compared with mechanical prostheses. The purpose of this study was to evaluate the incidence of cerebrovascular events during long-term follow-up after stentless aortic valve replacement. METHODS Between 1996 and 2005, 1,014 patients (mean age, 73 years; range, 20 to 90 years) received stentless aortic valve replacement (Freestyle; Medtronic, Minneapolis, MN) and were included into the systematic follow-up that was closed in 2006 with a completeness of 94.7% and a mean follow-up interval of 3 years (range, 0.5 to 9.8 years). Predictors for freedom from cerebrovascular events were identified by Cox regression. RESULTS Overall survival was 53% +/- 5% after 8 years (mean, 6.8 +/- 0.2 years). Permanent atrial fibrillation at time of surgery was a strong predictor of impaired survival during follow-up. Freedom from cerebrovascular events during follow-up was 68% +/- 5% at 9 years of follow-up. Multivariate regression analysis revealed previous stroke, age at implant, diabetes mellitus, and carotid lesions as significant risk factors. Especially age older than 75 years was a strong risk factor for cerebrovascular events during follow-up (p = 0.004). Atrial fibrillation was not an independent risk factor for cerebrovascular events (p = 0.26) but was a strong predictor of poor survival (p < 0.001) during follow-up. There was no influence of technique of implantation (subcoronary versus full root; p = 0.41), sex (p = 0.35), additional bypass grafting (p = 0.65), and the size of the implanted prosthesis (p = 0.47). CONCLUSIONS The risk of cerebrovascular events during follow-up after stentless aortic valve replacement is related to the individual risk factors of the patients rather than to the valve prosthesis itself. Without additional risk factors, patients with these aortic valve prostheses showed an incidence of cerebrovascular events similar to those reported for a healthy population adjusted for age.

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

BackgroundDespite 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.MethodsGroup 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.ResultsThe 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.ConclusionBilateral 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.

Outcome of heart surgery procedures in octogenarians: is age really not an issue?

Survival rates are a well-known marker for quality performance of a cardiac surgery department, as well as standard of procedures, freedom of reoperation, postoperative complications, length of hospital stay, improvement in New York Heart Association classification and quality of life after surgery. Until recently there has not been any great interest of surgeons in topics concerning the costs of postoperative care, as long as the results were successful. However, satisfactory results after cardiac surgery in aged people require successful procedures, as well as meticulous perioperative care. The expenses of healthcare are constantly growing and approaches to optimize costs in all departments of medicine have a high priority. Exact evaluation of comorbidities and prevention of complications in aged people, as well as attentive strategies concerning expenses, may help to reduce mortality, postoperative complications and costs.

Gadolinium-enhanced elliptically reordered three-dimensional MR angiography in the assessment of hand vascularization before radial artery harvest for coronary artery bypass grafting: first experience.

Winterer JT, Ennker J, Scheffler K, et al. Gadolinium-enhanced elliptically reordered three-dimensional MR angiography in the assessment of hand vascularization before radial artery harvest for coronary artery bypass grafting: First experience. Invest Radiol 2001;36:501–508. rationale and objectives. To assess the suitability of contrast-enhanced magnetic resonance angiography (MRA) in the preoperative evaluation of hand vasculature in potential candidates for radial artery bypass grafting. methods.In 21 patients, gadobenate dimeglumine–enhanced, three-dimensional gradient-echo sequences of both hands were performed, as well as a Doppler ultrasound study with radial artery compression. Doppler findings were correlated with MRA, focusing on the assessment of anastomoses between the vascular bed of the ulnar and radial arteries. results.One individual had to be excluded because of accidentally disclosed metal foreign bodies. Sufficient depiction of the hand vasculature was achieved in the remainder. Seventeen patients had evidence of adequate collateral flow between the ulnar and radial artery supply on Doppler ultrasound. Three patients exhibited inadequate collateral flow, with angiographic signs of vessel occlusion or missing collaterals between the palmar arches. Two patients presented with stenosis or occlusion of the radial artery. Magnetic resonance angiograms displayed great variations in hand vasculature and collateral formation, with no mismatch compared with Doppler ultrasound results. conclusions.Contrast-enhanced MRA displays vascularization of the hand in detail and supplies ultrasound flow measurements for radial artery harvest, with high-resolution angiographic data about possible vessel variations and the presence of anastomoses between the radial or ulnar artery supply.