Cardiac surgery for octogenarians--a suitable procedure? Twelve-year operative and post-hospital mortality in 641 patients over 80 years of age.

OBJECTIVES: The increase in life expectancy as a result of therapeutic improvements subsequently leads to a large number of patients with advanced age. The aim of this study was to review the 30-day mortality and mid-term outcome of octogenarians undergoing coronary artery bypass grafting (CABG) or valve replacement (AVR/MVR). METHODS: The data of 641 patients with a mean age of 82.6 years (range 80.0 - 92.6), operated between 9/93 and 12/05, were reviewed. 432 patients underwent CABG, 188 had AVR and 21 had MVR. We analysed peri-/postoperative mortality and clinical outcomes. Follow-up was obtained by phone contact with patients or their physician. Mid-term survival was determined for the whole population by the Kaplan-Meier method; peri- and postoperative risk factor analysis was done using logistic regression. Follow-up ranged from 0.1 to 11.8 years (mean 3.6 +/- 2.6) and was complete for 99%. RESULTS: We observed a perioperative mortality of 8.8% for CABG, 4.8% for AVR and 9.5% for MVR. Perioperative mortality was strongly associated with urgent/emergent operations (P < 0.03), poorer clinical status (P < 0.03), renal dysfunction (P < 0.05) and male gender (P < 0.04). Actuarial survival after 3, 5 and 8 years was as follows: CABG 78%, 66% and 44%; AVR 79%, 68% and 38%; MVR 76%, 61% and 23%. The mean NYHA functional class for survivors improved in the group of patients with CABG from 2.7 to 2.0 (P < 0.03), in the AVR group from 2.8 to 2.0 (P < 0.03), and in the MVR group from 2.9 to 2.3 (P < 0.05). More than 80% of all surviving patients live at home, either alone or with their family. CONCLUSION: In our cohort of octogenarians, cardiac surgery was found to be associated with an acceptable, although increased perioperative mortality. Despite the enhanced perioperative risk, the clinical benefit, as verified by improved functional status and satisfactory mid-term survival rates, justifies surgery in these patients with advanced age.

Is extreme obesity a risk factor for increased in-hospital mortality and postoperative morbidity after cardiac surgery? Results of 2251 obese patients with BMI of 30 to 50.

OBJECTIVE: The number of patients with extreme obesity requiring cardiac surgery is increasing. The aim of the present study was to evaluate the perioperative outcome, complication rate and 30-day mortality of these patients. METHODS: Data of 13 139 patients (9584 males, 3555 females) undergoing cardiac surgery from 1/94 to 12/04 were analyzed. We compared 2251 obese patients with a BMI of 30 to 50 (mean age 64.3 years; group A) with 10 888 non-obese patients (mean age 66.1 years; group B). The incidence of diabetes mellitus was 34.5 % in group A, and 24.2 % in group B. RESULTS: Isolated CABG was performed in 1771 patients from group A (3.4 grafts/pt.) and in 8066 patients from group B (3.2 grafts/pt.). Concomitant procedures were performed in 460 patients (group A) vs. 2645 (group B). Frequency of bilateral internal thoracic artery grafting was 49.4 % (group A) vs. 44.9 % (group B). There were no significant differences between the two groups with regard to the duration of surgery (180 vs. 171 min), the number of reoperations for bleeding (4.7 % vs. 5.0 %), ventilation times, length of stay in the intensive care unit (2.6 vs. 2.4 days) or 30-day mortality (2.0 % vs. 2.8 %). The incidence of diabetes and occurrence of sternal dehiscence was higher in group A (1.6 % vs. 0.7 %; P < 0.01). Sternal complications were strongly associated with diabetes and the combined use of bilateral ITA grafts but not with isolated obesity. The incidence of sternal dehiscence was associated with the male gender (group A 1.9 % vs. 0.7 %; group B 0.9 % vs. 0.3 %). CONCLUSION: Severe obesity does not PER SE enhance perioperative mortality. A BMI of 30 to 50 combined with diabetes mellitus and bilateral ITA grafting increases the risk for sternal complications.

Patency of internal thoracic artery compared to vein grafts - postoperative angiographic findings in 1189 symptomatic patients in 12 years.

BACKGROUND: The evidence respecting the superior patency of ITA-grafts compared to SVG is conclusive. This study evaluates the angiographic findings in 1,189 symptomatic patients who received either one or both ITA-grafts with or without additional SVG. METHODS: 1,189 patients (975 males, aged 62.4 +/- 9.1 years), operated between 2/93 and 7/05, underwent angiography due to reappearance of angina. Data were compared for patency of single ITA (n = 618), bilateral ITA (n = 416) or SVG (n = 2,218). Re-catherization was performed after 3.8 +/- 2.7 years. Severe bypass stenosis or graft occlusion was related to the target vessels. RESULTS: 3,668 bypasses were performed in 1189 patients. The occlusion rate was 16.5 % for SVG and 7.0 % for all ITAs ( P < 0.001). Severe stenosis was detected in 4.8 % of SVG and in 3.7 % of ITAs ( P < 0.05). Patency was 89.6 % for LITA, 88.7 % for RITA, and 78.7 % for SVG. The occlusion rate for LITA was: to LAD 6.6 %, DIA 8.5 %, obtuse marginal branch/CX 11.5 %. The occlusion rate for RITA was: to LAD 4.6 %, RCA 9.1 %., diag. branch 7.1 %. The occlusion rate for vein grafts was: to LAD 17.3 %, DIA 14.4 %, obtuse marginal branch/CX 15.9 %, to RCA 17.0 %. Patency for all ITAs was 89.3 % vs.78.7 % for all SVG ( P < 0.05). Despite symptoms, bypass patency was found in 711 patients (59.8 %). CONCLUSION: The superior patency of ITA-grafts could be documented angiographically in a negatively selected, symptomatic population. Graft occlusion was at least twofold higher for SVG.

Double thoracic artery--halved mid-term mortality? A 5-year follow-up of 716 patients receiving bilateral ITA versus 662 patients with single ITA.

UNLABELLED: The superior patency of ITA grafts to saphenous veins is conclusive. The aim of the study was to collate mid-term benefit between patients receiving bilateral ITA (BITA) or single ITA (SITA). Outcome of 1378 pts with isolated CABG operated between 1/97-8/99 was analyzed retrospectively. Follow-up was 4.0 to 6.6 years (average 5.3). A total of 716 pts received BITA, 662 SITA and additional saphenous veins. We evaluated mortality rate, freedom from reoperation, intervention (PTCA/stent), and incidence of cardiac events and quality of life with respect to pts risk factors. Demographic data: Male gender was more frequent in both groups (BITA females: n=115; males: n=601; SITA females: n=150; males: n=512; p<0.01). Mean age was comparable in both groups with 69.2 years (42.7 to 88.6 years) in the BITA group and 71.0 years (47.3 to 91.6 years) (n. s.) in the SITA group. RISK FACTORS: Incidence of diabetes mellitus (26.0 vs 25.9%) as well as the mean BMI (27.4 vs 27.0%) did not differ statistically in both groups. RESULTS: Clinical characteristics like NYHA/ CCS classifications showed a significant difference towards superior results only for stadium I in the BITA group. Mortality/cardiac events after 5.3 years average: Total mortality revealed 5.2% (n=37) in the BITA vs 9.1% (n=60) in the SITA group (p

Is there a difference between diabetic and non-diabetic ITAs? Histomorphological and immunohistochemical examinations of internal thoracic arteries.

BACKGROUND: The relative resistance to arteriosclerosis of the internal thoracic artery is clinically valid. The aim of this study was to evaluate the graduation of intima and media fibrosis in ITA parts and to determine the extent of atherosclerosis using immunohistochemical methods related to patients' risk factors. METHODS: 227 distal ITA segments from 144 male and 83 female patients were examined. Mean age was 66.7 +/- 9.03 years. HE and Elastica van Gieson staining was performed to detect intima-/mediafibrosis. POPULATION: insulin-dependent diabetes mellitus (idDM; n = 35), non-insulin-dependent diabetes mellitus (nidDM; n = 32), irradiation of the chest due to cancer (n = 27), control group with isolated hyperlipidemia, hypertension, peripheral vascular disease (n = 133). 12 ITA segments of each group were examined immunohistochemically using CD34, CD68, Tenascin, Collagen III, Collagen IV. RESULTS: Histomorphological examinations using HE and Elastica van Gieson stainings showed for idDM-ITAs no fibrosis in 57 %, slight fibrosis in 34 %, medium in 6 %, no severe, for nidDM-ITAs no fibrosis in 63 %, slight 31 %, medium 3 %, severe 3 %, for ITAs after irradiation: no fibrosis in 37 %, slight in 62 %, no medium or severe fibrosis. Compared to the control group there was no statistically significant difference in diabetic ITAs. Immunohistochemical examinations, scored on a 0 - 3 basis with 0 being the lowest (no reaction), 3 the highest (severe reaction), showed mostly no or slight reaction to CD34, CD68, Tenascin, and Collagen III for intima and media, with comparable results for diabetic or "irradiated" ITAs to those of the control group. The most distinct reaction (medium= 2), was detected for Collagen IV, a marker which outlines basement membranes of endothelia and smooth muscle cells of the vessel wall, but without differences between the four groups. No severe reactions were observed. CONCLUSIONS: The relative resistance of ITA to arteriosclerosis could be demonstrated in 227 ITA segments. Immunohistochemistry supports histomorphological findings. The influence of diabetes mellitus and irradiation remains irrelevant.

Are men treated better than women? Outcome of male versus female patients after CABG using bilateral internal thoracic arteries.

BACKGROUND: Apart from smaller native coronary arteries a lower number of anastomoses and a lower ITA incidence have been suggested as being responsible for the increased mortality in female patients compared to males. The aim of this study was to clarify whether the outcome of females might be a consequence of a different regimen in anastomosis and ITA frequency. METHODS: We evaluated operative data and early outcome of 6906 patients with isolated CABG operated between 1/96 - 7/03 3064 out of 5381 males received bilateral ITA (BITA) vs. 750 of 1525 females. Single ITA (SITA) was performed in 2126 males and 704 females. RESULTS: Demographic and operative data: average age for male patients was 64.0 +/- 9.2 years, for females 68.5 +/- 8.6 years ( p < 0.05). The prevalence of diabetes mellitus was significantly higher in females (34.6 % vs. 27.4 %, p < 0.01). Body mass index (BMI, 26.6 vs. 27.4 mean), incidence of main stem stenosis (23.0 % vs. 23.5 %), ejection fraction < 40 % (7.8 % vs. 10.1 %), urgent or emergent operations (13.1 % vs. 11.3 %) and number of performed anastomoses (3.2 vs. 3.5 mean) showed no significant difference between males and females. Total ITA frequency did not differ (95.3 % vs. 96.5 %), but BITA frequency was significantly higher (56.9 % vs. 49.2 %, p < 0.01) in male patients. Overall 30-day mortality was 2.8 % for males vs. 4.1 % ( p < 0.05) for females. Cardiac-related mortality was significantly higher in female patients (2.6 % vs. 1.1 %, p < 0.01). Non-cardiac-related mortality did not differ significantly. Graft-related mortality for males and females revealed 2.7 % in the BITA, 3.3 % in the SITA group and 6.9 % for patients without ITAs and reached statistical significance ( p < 0.01) for SITA or BITA vs. the no-ITA group, but not for BITA vs. SITA grafting. Nevertheless cardiac-related mortality in male and female patients without an ITA graft was more than two-fold higher compared to these with single ITAs and more than three-fold higher compared to those with BITA grafting. CONCLUSIONS: Female gender, frequently associated with diabetes mellitus, presents a predictor for increased mortality in CABG. A discrimination of women with respect to a restriction of ITA grafting could be confirmed only for bilateral ITAs. The superior results of bilateral ITA grafts are independent of gender.

[Urgent or emergent coronary revascularization using bilateral internal thoracic artery after previous clopidogrel antiplatelet therapy]. / Dringliche oder notfallmässige Koronarrevaskularisation unter Verwendung beider Arteria Thoracica interna nach vorheriger Thrombozytenaggregationshemmung mit Clopidogrel.

BACKGROUND: Application of clopidogrel before diagnostic or therapeutical percutaneous coronary interventions has become standard for stent-thrombosis prevention. The irreversible platelet inhibition causes increasing bleeding complications if urgent coronary artery bypass grafting becomes necessary. This study evaluates the effect on bleeding complications of clopidogrel in urgent CABG using bilateral internal thoracic artery (ITA) and saphenous veins in all patients. METHODS: We retrospectively analyzed 166 patients (operated between 1/00-12/02) with urgent or emergency CABG, using both ITAs and compared 83 patients with previous (within 5 days) clopidogrel and aspirin application to 83 patients without clopidogrel. We evaluated chest tube output, reexploration rate and necessity of blood products, ventilation time and ICU stay. RESULTS: Both groups were comparable with age, gender, number of performed anastomoses (mean 4/ patient). Chest tube output (24 h) was higher in the clopidogrel group (935 +/- 599 ml vs 754 +/- 335 ml (p = 0.018)), as well as reexploration rate with 7.2% (6 of 83) vs 0% (0 of 83) (p < 0.001). Number of blood products in the clopidogrel group for red cells was 2.41 +/- 1.88 U vs 1.84 +/- 1.47 U p = 0.03, for plateletes 0.43 +/- 0.88 U vs 0.024 +/- 0.22 p = 0.0001, for fresh frozen plasma 0.41 +/- 1.14 U vs 0.096 +/- 0.59 U p = 0.029. Mechanical ventilation time was 11.35 +/- 8.77 h vs 10.57 +/- 9.12 h p = 0.51, ICU stay 32.1 +/- 21.8 h vs. 29.8 +/- 21.1 h (p = 0.48). CONCLUSIONS: Previous application of clopidogrel in combination with aspirin before urgent CABG induces increased chest tube output, reexploration rate and necessity of blood products, especially of plateletes. Nevertheless, routine use of both ITAs in patients after clopidogrel exposure can be performed with acceptable bleeding complications.

Mid-term hemodynamic and clinical results of the stented porcine medtronic mosaic valve in aortic position.

BACKGROUND: Our study aim was to evaluate the hemodynamic and clinical performance of the Mosaic bioprosthesis in aortic position. METHODS: The stented porcine bioprosthesis combines zero pressure glutaraldehyde fixation and amino oleic acid antimineralization treatment for improved hemodynamics and durability. Between 2/1994 and 5/1999, 100 patients underwent aortic valve replacement. Mean age at implant was 73.4 years. Patients were followed up within thirty days after intervention, after six months and then annually. Mean follow-up was 4.8 years (range 0.1-8.8 years), totaling 483.4 patient-years. RESULTS: Mortality within 30 days was 3.0 %; late mortality was 4.6%/patient-year, including 0.4 %/patient-year prosthesis-related mortality. Freedom from event rates at 8.5 years were 96.8% for thromboembolism, 97.7% for thrombosed bioprosthesis, 97.4% for structural deterioration, 98.7% for nonstructural dysfunction, 95.9 % for hemorrhage, 98.9% for endocarditis and 95.1 % for reoperation and explant. Mean pressure gradients were 15.2 mm Hg (21), 14.5 mm Hg (23), 12.7 mm Hg (25) and 13.0 mm Hg (27) after one year; effective orifice areas 1.36 cm2 (21), 1.68 cm2 (23), 1.76 cm2 (25) and 2.57 cm2 (27). CONCLUSIONS: Clinical and hemodynamic performance of the Mosaic bioprosthesis was highly satisfactory during the first 8.5 years after clinical introduction.

[Simultaneous carotid endarterectomy and cardiac surgery-additional risk factor or safe procedure?]. / Thrombendarteriektomie der Arteria carotis und simultane Herzoperation. Zusätzlicher Risikofaktor oder sichere Vorgehensweise?

BACKGROUND: The occurrence of severe carotid artery disease in more than 12% of patients requiring ACB results in a discrepancy concerning the best treatment for both diseases. We reviewed the early outcome of patients with ACB and/or valve replacement and simultaneous carotid endarterectomy (TEA). METHODS: We evaluated retrospectively 244 patients operated simultaneously between 7/94 and 10/2001: 209 patients received ACB, 35 patients ACB and/or valve replacement. Mean age was 68 years. 188 patients were male. We analyzed risk factors, morbidity, incidence of neurological complications and 30 day mortality. RESULTS: Perioperative stroke with hemiplegia occurred in 3.3% (8 patients). Of these patients, 4 showed contralateral carotid artery occlusion, 2 contralateral severe stenosis. Two patients (0.8%) experienced prolonged reversible ischemic neurological deficit (PRIND), 4 patients (1.6%) transient ischemic attack (TIA). 30-day morbidity was 4.5%. Three patients died due to low cardiac output, 6 patients due to extracardial reasons, 2 patients (0.8) due to cerebral death. CONCLUSION: Simultaneous TEA and cardiac surgery can be performed with an acceptable risk for neurological complications and mortality. Occlusion of the contralateral carotid artery could be identified as an evident predictor for increased neurological complications. Compared to two-stage procedures, combined operations yield a reduction of hospital costs.

Internal thoracic artery vs. vein grafts--postoperative angiographic findings in symptomatic patients after 1000 days.

BACKGROUND: Superior patency-rate of ITA, especially BITA-grafting to saphenous vein grafts, is conclusive. This study evaluates angiographic findings postoperatively in 663 symptomatic patients receiving one or both ITAs and vein grafts. METHODS: 663 patients (553 male, mean age 62) with CABG operated between 1/94 and 6/02 underwent reangiography due to reappearance of angina or unclear cardiac symptoms. Angiographic data were compared for patency rate of single ITA (n = 379), bilateral ITA (n = 220) or vein grafts. Recatherization was performed after an average of 1000 days (+/- 766 days). Severe bypass stenosis or occlusion was related to target vessels for all grafts. RESULTS: 2099 Bypasses were performed in 663 patients. Severe stenosis or occlusion was detected in 255 ACB (19.9 %) of 1280 and 93 ITAs of 819 (11.4 %, p < 0.001). Patency was 88.8 % (532) for LITA, 88.2 % (194) for RITA. Target vessels were as follows: LITA: 60 % (358) LAD, 23.5 % (141) CX, RITA: 82 % (180) LAD. Occlusion rate for LITA was as follows: to LAD 7 %, to DIA 8.7 %, to CX 8.5 %. Occlusion rate for RITA as follows: to LAD 6.7 %, to DIA 16.7 %, to CX 0, to RCA 14.3 %. Occlusion rate for ACB was as follows: to LAD 18.7 %, to DIA 12.6 %, to CX 14.1 %, to RCA 16.1 %. Despite symptoms, bypass patency was observed in 412 (62.1 %) of 663 patients. CONCLUSIONS: Superior patency of ITA, especially BITA grafting could be documented angiographically in a negative selected symptomatic population. Graft occlusion was nearly two fold higher in vein grafts. Our surgical strategy, revascularizising RITA with LAD, LITA with circumflex artery results in satisfactory mid-term graft patency.

[End of the millennium - end of the single mammary artery graft? Two internal mammary arteries - standard for the next millennium? Early clinical results and analysis of risk factors in 1487 patients with bilateral internal mammary artery bypass]. / Ende eines Jahrtausends--Ende des Einfach-Mammaria-Bypasses. Zwei Arteriae mammariae internae--Standard für das nächste Jahrtausend? Klinische Ergebnisse und Risikofaktorenanalyse von 1487 Patienten mit bilateralem Arteria mammaria interna Bypass.

OBJECTIVE: CABG with bilateral IMA grafts (BIMA) can improve long-term results in cardiac morbidity and mortality. An enhanced incidence of bleeding and wound complications compared to patients with single IMA (SIMA) remains a matter of debate. The aim of the study was to compare the operative outcomes of patients who had undergone CABG with BIMA and SIMA in situ grafts, especially to identify patient-related risk factors, such as obesity, diabetes mellitus and age above 70 years. METHODS: Out of a total of 5144 patients operated on between January 1996 and September 1999, patients with isolated CABG (n = 3671) with BIMA or SIMA were analyzed retrospectively. In the BIMA group, the patients' (n = 1478) mean age was 64.0 years; mean EF was 62.1%. In the SIMA group (n = 2184), mean age was 65.4 years and mean EF was 60.6% (n.s.). In the BIMA group, the right IMA was led anterior of the aorta to the LAD, the left IMA to the lateral wall. In the SIMA group, the LAD was revascularized with the left IMA. Additional bypasses were performed with vein grafts. RESULTS: The 30-day mortality was 1.6% in the BIMA group, 1.7% in the SIMA group in patients under 70 years, and 4.1% (BIMA) and 4.0% (SIMA) in patients over 70 years (p = n.s.). A significantly higher blood loss was observed in the BIMA group (BIMA 979 +/- 708 ml; SIMA 790 +/- 575 ml; p < 0.05). The rethoracotomy rate due to bleeding was significantly higher in patients with BIMA (4.1%) compared to those with SIMA (2.5%; p < 0.05). In patients with a body mass index (BMI) of less than 27, no significant difference could be found (SIMA 2.8%, BIMA 3.4%; p = n.s.). Patients with a BMI > 27 showed a significantly higher rethoractomy rate (SIMA 2.2%; BIMA 4.9%). A higher incidence of sternal instabilities could be observed in the BIMA group (4.2%; p < 0.05). Diabetes mellitus could not be identified as an independent risk factor for sternal complications (SIMA 2.9%; BIMA 5.0%; p = n.s.). CONCLUSION: CABG using both IMAs can be performed in nearly all patients as a routine method with good clinical results and low mortality. Bleeding in the BIMA group within 48 h was increased. BMI > 27 could be identified as a risk factor for sternal complications, but not diabetes mellitus or age over 70 years.

[Clinical and hemodynamic results of the mosaic bioprosthesis in aortic position]. / Klinische und hämodynamische Ergebnisse der Mosaic Bioprothese in Aortenposition.

INTRODUCTION: Aim of the study was to evaluate the hemodynamic and clinical performance of the Mosaic bioprosthesis in the aortic position. PATIENTS AND METHODS: The Mosaic bioprosthesis is a stented porcine heart valve for implantation in the aortic and mitral position, which combines zero pressure and root pressure fixation with glutaraldehyde, antimineralization treatment with alpha amino oleic acid (AOA) and a low profile stent, to optimize hemodynamic function and to minimize mechanical wear and thus to achieve longer tissue durability. Included in a multicenter study, 100 patients (49 females) underwent isolated aortic valve replacement with the Mosaic bioprosthesis between February 1994 and May 1999. Average age at implant was 73.4 +/- 7.3 years (range 31.3-86.8 years). Preoperative and operative clinical data are shown in Tables 1 and 2. Patients were followed-up within the first 30 postoperative days, after six months and at annual intervals, including transthoracic echocardiography and documentation of any adverse events. Mean follow-up was 3.8 years (range 0.1-7.1 years), total 383.1 patient-years. Follow-up is 100% complete. RESULTS: One year after implantation of the bioprosthesis, mean systolic pressure gradient was 15.3 +/- 6.7 mmHg (21), 14.5 +/- 5.7 mmHg (23), 12.7 +/- 4.1 mmHg (25) and 13.0 +/- 4.8 mmHg (27); effective orifice area (EOA) was 1.4 +/- 0.4 cm2 (21), 1.7 +/- 0.4 cm2 (23), 1.8 +/- 0.4 cm2 (25) and 2.6 +/- 0.4 cm2 (27) (Table 3). One year postoperative, nine patients (10.8%) showed mild aortic regurgitation and one patient (1.2%) moderate. Left ventricular mass index decreased significantly for all sizes within the first postoperative year from 159.7 +/- 56.8 g/m2 to 137.3 +/- 40.8 g/m2. Separating the patients with regard to valve size, only the 21-group (154.1 +/- 51.2 g/m2 to 129.1 +/- 34.6 g/m2) and the 27-group (237.7 +/- 59.2 g/m2 to 146.7 +/- 20.6 g/m2) showed significant results. Freedom from event rates at seven years were 96.8 +/- 1.8% for thromboembolic events, 97.2 +/- 2.0% for thrombosed bioprosthesis, 96.6 +/- 2.6% for structural valve deterioration, 98.2% +/- 1.8% for nonstructural dysfunction, 95.9% +/- 2.0% for antithromboembolic hemorrhage, 98.9 +/- 1.1% for endocarditis and 93.9 +/- 3.2% for reoperation and explant (see Table 4). Early mortality (within 30 days) was 3.0%; late mortality was 4.6%/patient-year, including a valve-related mortality of 0.6%/patient-year. Of the patients, 96.5% showed an improvement of at least one NYHA class when comparing preoperative and one year status. DISCUSSION: The hemodynamic performance and the frequency of adverse events of the Mosaic bioprosthesis in the aortic position were very satisfactory within the first seven postoperative years with excellent results, comparable to studies about other established bioprostheses and similar to the findings in other Mosaic series. Only the number of cases of antithromboembolic hemorrhage was noticeably high. One reason might be the high percentage of patients under continuous anti-coagulant therapy: Six months postoperative, still 52.2% of the patients received phenprocoumon, 6.7% acetylsalicylic acid. Concerning hemodynamics, patient-prosthesis mismatch appeared to be a common problem, especially in small valve sizes. Separating the sample in groups with EOA index < or = 0.75 cm2/m2 and EOA index > 0.75 cm2/m2 after one year, 51.6% in the 21-group had an EOA index < or = 0.75 cm2/m2, whereas it was 19.4% (23), 18.8% (25) and 0% (27) in the larger size groups. Generally, further data have to be collected to determine durability of the biological tissue, as the critical period has just started with the seventh year of the clinical trial. CONCLUSION: The Mosaic bioprosthesis proved to be a reliable and well-functioning device for aortic valve replacement, especially in larger sizes.

Urgent or emergent coronary revascularization using bilateral internal thoracic artery after previous clopidogrel antiplatelet therapy.

BACKGROUND: Clopidogrel application before diagnostic or therapeutical percutaneous coronary intervention has become the standard for stent thrombosis prevention. Irreversible platelet inhibition causes increasing bleeding complications if urgent coronary artery bypass grafting is necessary. This study evaluates the effect on bleeding complications of clopidogrel in urgent CABG using bilateral internal thoracic artery (ITA) and saphenous veins in all patients. METHODS: We retrospectively analyzed 128 patients (operated between January 2000 and September 2002) undergoing urgent or emergent CABG using both ITAs, and compared 64 patients with previous clopidogrel and aspirin application (within 5 days) to 64 patients without clopidogrel. We evaluated chest tube output, re-exploration rate and necessity of blood products, ventilation time and ICU stay. RESULTS: Both groups were comparable in age, gender, number of performed anastomoses (mean 4/patient). Chest tube output (24 h) was higher in the clopidogrel group at 977+/-628 ml vs. 788+/-389 ml (p=0.046), as was re-exploration rate with 7.81% (5 of 64) vs. 0% (0 of 64) (p<0.005). The number of blood products amounted to 2.7+/-1.9 U in the clopidogrel group vs. 1.9+/-1.6 U (p=0.013) for red cells, 0.05+/-0.9 U vs. 0.03+/-0.25 (p=0.0003) for platelets, and 0.5+/-1.3 U vs. 0.2+/-1.0 U (p=0.14) for fresh frozen plasma. Mechanical ventilation time was 11.9+/-9.7 h vs. 9.6+/-5.9 h (p=0.10), ICU stay 32.6+/-22.1 h vs. 27.8+/-18.2 h (p=0.19). CONCLUSIONS: Previous application of clopidogrel in combination with aspirin before urgent CABG induces increased chest tube output, re-exploration rate and necessity of blood products, especially platelets. Nevertheless, routine use of both ITAs in patients after clopidogrel exposure can be performed with acceptable bleeding complications.

Simultaneous carotid endarterectomy and cardiac surgery--additional risk factor or safety procedure?

BACKGROUND: The occurrence of severe carotid artery disease in more than 12 % of patients requiring CABG results in a discrepancy concerning the best treatment for both diseases. We reviewed the early outcome of patients with CABG and/or valve replacement and simultaneous carotid endarterectomy (CEA). METHODS: We evaluated retrospectively 244 patients operated simultaneously between 7/94 and 10/2001. 209 patients received CABG; 35 patients CABG and/or valve replacement. Mean age was 68 years. 188 patients were male. We analyzed risk factors, morbidity, incidence of neurological complications and 30 day mortality. RESULTS: Perioperative stroke with hemiplegia occurred in 3.3 % (8 patients). 4 of these patients showed contralateral carotid artery occlusion, 2 contralateral severe stenosis. 2 patients (0.8 %) experienced prolonged reversible ischemic neurological deficit (PRIND), 4 patients (1.6 %) transient ischemic attack (TIA). 30-day lethality was 4.5 %. 3 patients died due to low cardiac output, 6 patients due to extracardial reasons, 2 patients (0.8 %) developed a cerebral death. CONCLUSIONS: Simultaneous CEA and cardiac surgery can be performed with an acceptable risk for neurological complications and mortality. Occlusion of contralateral carotid artery could be identified as an evident predictor for increased neurological complications. Compared to two-stage procedures, combined operations yield a reduction of hospital costs.

End of the millenium--end of the single thoracic artery graft? Two thoracic arteries--standard for the next millenium? Early clinical results and analysis of risk factors in 1,487 patients with bilateral internal thoracic artery grafts.

PURPOSE: CABG with bilateral IMA grafts (BIMA) can improve long-term results in cardiac morbidity and mortality. An enhanced incidence of bleeding and wound complications compared to patients with single IMA (SIMA) remains a matter of debate. The aim of the study was to compare the operative outcomes of patients who had undergone CABG with BIMA and SIMA in situ grafts, especially to identify patient-related risk factors, such as obesity, diabetes mellitus and age above 70 years. METHODS: Out of a total of 5,144 patients operated on between January 1996 and September 1999, patients with isolated CABG (n = 3,671) with BIMA or SIMA were analyzed retrospectively. In the BIMA group, the patients' (n = 1,487) mean age was 64.0 years; mean EF was 62.1%. In the SIMA group (n = 2,184), the mean age was 65.4 years and mean EF 60.6% (n. s.). In the BIMA group, the right IMA was anterior of the aorta to the LAD, the left IMA to the lateral wall. In the SIMA group, the LAD was revascularisized with the left IMA. Additional bypasses were performed with vein grafts. RESULTS: The 30-day lethality was 1.6% in the BIMA group, 1.7% in the SIMA group in patients under 70, and 4.1% (BIMA) and 4.0% (SIMA) in patients over 70 (p = n.s.). A significantly higher blood loss was observed in the BIMA group (BIMA 979+/-708 ml, SIMA 790+/-575 ml, p<0.05). The rethoracotomy rate due to bleeding was significantly higher in patients with BIMA (4.1%) compared to those with SIMA (2.5%, p<0.05). In patients with a body mass index (BMI) of less than 27, no significant difference could be found (SIMA 2.8%, BIMA 3.4%, p = n. s.). Patients with a BMI >27 showed a significantly higher rethoracotomy rate (SIMA 2.2%, BIMA 4.9%). A higher incidence of sternal instabilities could be observed in the BIMA group (4.2%, p<0.05). Diabetes mellitus could not be identified as an independent risk factor for sternal complications (SIMA 2.9%, BIMA 5.0%, p = n. s.). COUCLUSION: CABG using both IMA's can be performed in nearly all patients as a routine method with good clinical results and low mortality. Bleeding in the BIMA group within 48 hours was increased. BMI >27 could be identified as a risk factor for sternal complications, but not diabetes mellitus or age over 70 years.

The Mosaic bioprosthesis in the aortic position at five years.

BACKGROUND AND AIM OF THE STUDY: The study aim was to collect intermediate-term data on the Mosaic bioprosthesis implanted in the aortic position. The device has been in clinical use since February 1994. METHODS: The Mosaic bioprosthesis is a stented porcine aortic valve, which combines a zero pressure differential fixation technique and anti-mineralization treatment with amino oleic acid for improved tissue durability. Between February 1994 and May 1999, 100 patients (49 females, 51 males; mean age at implant 73.4 +/- 7.3 years (range: 31-87 years) underwent aortic valve replacement with the Mosaic prosthesis in our department. Concomitant procedures were performed in 40% of cases. Patients were followed up prospectively at annual intervals; the mean follow up was 2.7 years (total 273.7 patient-years (pt-yr)) and was 100% complete. RESULTS: Total early mortality (within 30 days) was 3.0%; the late mortality rate was 4.4%/pt-yr and included a valve-related mortality rate of 0.7%/pt-yr. The freedom from event rates at five years were 97.3 +/- 1.9% for permanent neurological, 99.0 +/- 1.0% for transient neurological, 95.9 +/- 3.2 for thrombosed prosthesis, 95.6 +/- 2.2% for anti-thromboembolic-related hemorrhage, 100% for primary valvular leak, 96.9 +/- 3.0% for non-structural dysfunction, 100% for endocarditis, and 92.0 +/- 4.9% for explant. The mean systolic gradients were 15.2, 13.1 and 10.1 mmHg for the 21, 23 and 25 mm valve sizes, respectively. CONCLUSION: The clinical and hemodynamic performance of the Mosaic prosthesis was highly satisfactory during the first five years after clinical introduction. Further data will be necessary to confirm long-term durability.

[Mosaic bioprosthesis after 5 years]. / Mosaic-Bioprothese nach fünf Jahren.

The Mosaic bioprosthesis is a stented porcine aortic valve, which combines the zero pressure differential fixation technique (by applying equal pressure to the in- and outflow ends of the valve, the aortic root is pressurized to maximize the flow area while no pressure is exerted on the leaflets) and an antimineralization treatment with alpha amino oleic acid for improved tissue durability. The device is in clinical use since February 1994. The purpose of this study was to collect intermediate term data of the Mosaic bioprosthesis in the aortic position to evaluate its clinical and hemodynamic function. From February 1994 to May 1999, 100 patients underwent aortic valve replacement with the Mosaic prosthesis at our department. There were 49 female patients, mean age at implant was 73.4 +/- 7.3 years (range 31 to 87). Concomitant procedures were done in 40%. Preoperative and operative clinical data are shown in Tables 1 and 2. When assessing the size of the bioprosthesis, it is important to use the original Mosaic sizer. Because of the possibility of the so-called supra-x placement, the specific construction of the sizer and the Mosaic valve often allow the implantation of a 1-size larger valve compared to the conventional supra-annular placement. By this a significant increase in the effective flow orifice is possible. This proceeding is depicted in Figure 1. All patients have been anticoagulated with phenprocoumon at least for 3 months postoperatively, INR was aimed at 2.5 to 3.5. Patients have been followed up prospectively, within the initial hospitalization for valve replacement, 6 months postoperatively and at annual intervals including an hematological check and transthoracic echocardiography. The mean follow-up was 2.7 years with a total follow-up of 273.7 patient years. The follow-up was 100% complete. After 5 years the mean systolic pressure gradient was 15.2 +/- 3.0 mm Hg for the 21-mm, 13.1 +/- 4.6 mm Hg for the 23-mm, 10.0 +/- 3.1 mm Hg for the 25-mm valve size, the effective orifice area 1.6 +/- 0.3 cm2 (21-mm), 1.9 +/- 0.3 cm2 (23-mm) and 2.5 +/- 0.8 cm2 (25-mm) (see Table 3). The freedom from prosthesis-related event rates, calculated according to Kaplan-Meier, at 5 years were: 97.3 +/- 1.9% for permanent neurological, 99.0 +/- 1.0% for transient neurological, 95.9 +/- 3.2% for thrombosed prosthesis, 95.6 +/- 2.2% for antithromboembolic related hemorrhage, 96.2 +/- 3.7% for structural valve deterioration, 96.9 +/- 3.0% for non-structural dysfunction, 100% for endocarditis and 92.0 +/- 4.9% for explant (see Table 4). The total operative mortality (within 30 days) was 3.0%, the late postoperative mortality was 4.4% per patient year and included a valve related mortality rate of 0.7%/patient year. In Figure 2 the survival function after aortic valve replacement is depicted, arranged in freedom from all deaths, from Mosaic-related deaths and from Mosaic-related plus sudden/unexplained deaths. Before implantation of the Mosaic bioprosthesis 95% of the patients were in NYHA Classes III and IV, whereas 6 months postoperatively 98% could be classified in NYHA Classes I and II (see Figure 3). In relation to other biological prostheses (Intact, Carpentier-Edwards Pericardial and Porcine, Hancock Modified Orifice, Biocor, Freestyle) the Mosaic bioprosthesis showed very satisfactory and predominantly better hemodynamic results than the compared stented valves and approached the performance of stentless prostheses. The freedom rates from prosthetic-related adverse events of the Mosaic bioprosthesis were at least equivalent to the compared prostheses. However, the satisfactory freedom rates, especially from structural valve deterioration, should be qualified by considering the experience that most incidences appear from the 5th year on after implantation. The clinical and hemodynamic performance of the Mosaic prosthesis has been very satisfactory during the first 5 years after clinical introduction. Further data will be necessary to confirm long-term durability.

[Efficacy of metoprolol in prevention of supraventricular arrhythmias after coronary artery bypass grafting]. / Wirksamkeit der Metoprolol-Therapie in der Prävention supraventrikulärer Arrhythmien nach koronarer Bypass-Operation.

Atrial fibrillation is in 20-50% the most frequent dysrhythmia after coronary artery bypass grafting (CABG) and a possible cause for hemodynamical complications and prolongation off the medical treatment in patients. Therefore, the effect of beta-blocking with metoprolol for prevention of supraventricular arrhythmias (SVA) was investigated in a prospective and randomized trial. 200 patients after CABG were randomized in a drug and control group (average age 63.2 years, 154 male, 46 female). Patients of the drug group (n=100) were treated with metoprolol (1mg/kg/BW) beginning on day one after operation, whereas patients of the control group (n=100) received therapy only in case of occurrence of atrial fibrillation. ECG, blood pressure, and electrolyte concentrations were measured regularly until the tenth day after surgery. Reasons for exclusion were an ejection fraction (< 30%, SA- and AV-block or simultaneous application of epinephrine and metoprolol. There were no significant differences between the patients of drug and control group with respect to age, sex ejection fraction, previous medication, number and type of bypass grafts, cardiopulmonary bypass time, and perioperative ischemic events. However, a statistically significant difference was seen in the occurrence of supraventricular arrhythmias in both groups, 4 patients of the therapy group (4%) in contrast to 37 patients of the control (37%) developed supraventricular arrhythmias during the postoperative observation period (p<0.0001). Both groups differed in total time of hospital stay by 1.5 days (control group: 9.83+/-2.88 days; drug group: 8.42+/-2.81 days), which was statistically significant (p<0.05). All patients of the drug group could be discharged with a stable sinus rhythm, whereas 7 patients of the control group were discharged with persistent atrial fibrillation. The difference was statistically significant as well (p<0.01). Neither typical side effects of metoprolol, nor AV-blocks, bradycardia (f<60/min) or symptoms of low blood pressure could be observed. The conclusion of this trial is a recommendation for a preventive application of 50mg metoprolol/day after coronary artery bypass surgery, which can reduce the incidence of SVA as well as the hospital stay statistically significant.

Scintigraphy and immunohistology of antimyosin-Fab during graft rejection.

Up to now, the cellular localization pattern of monoclonal antimyosin antibodies (AMA) during acute rejection has not been described. Focused on this the authors made immunohistochemical and scintigraphic studies (AMS) with AMA in an animal transplantation model. Heterotopic cervical heart transplantation was performed in 12 mongrel dogs. Immunosuppression consisted of triple drug therapy. As standard the grafts were examined by daily transmural biopsies and routine histology. Dependent on the daily biopsy results, 0.5 mg of indium 111 ((111)In)-labeled AMA-Fab was injected. Subsequently every 2 hours transmural biopsy cylinders were taken out of the right ventricle and examined in indirect peroxidase staining technique. Forty-eight hours after AMA injection, scintigraphy in single photon emission computed tomography (SPECT) technique (AMS) was carried out and the heart-to-lung ratio (H/L-ratio) was calculated. The immunohistochemical maximum of AMA accumulation could be found 20 to 72 hours after AMA injection. This means that a scintigraphic examination should be done earlier than 20 hours and later than 3 days after injection. Dependent on the grades of bioptic rejection diagnosis a specific morphologic AMA localization was seen (grade I+II intercellular and slightly intracellular detection of AMA, grade III strongly intracellular and in particular perinuclear accumulation of the antibody, p<0.01). Moreover, the authors found a good correlation between scintigraphic H/L-ratio results and the corresponding histologic findings (grade I: H/L = 2.1 +/- 0.2; grade II: H/L = 3.1 +/- 0.2; grade III: H/L = 3.5 +/- 0.3; n = 19; p<0.02). The recently described positive AMS scans even in cases of mild rejection seem to be subject to an intercellular AMA localization. This typical AMA morphology during mild rejection favors the theory of the pore-forming protein allowing the efflux of myosin fragments as effector mechanism of cytotoxic lymphocytes in the early phase of acute rejection. The immunohistochemical AMA examination could explain the present discrepancy between positive AMS results of an intracellular protein in cases of mild or moderate acute rejection when visible cellular damage in the corresponding routine histology is absent.

[Using the internal thoracic artery of patients with reduced left ventricular function]. / Verwendung der Arteria thoracica interna bei Patienten mit reduzierter linksventrikulärer Funktion.

Todate internal mammary artery (IMA) is routinely used in coronary artery bypass grafting even in elder patients. However in patients with poor left ventricular function use of the IMA is discussed controversely in Germany. Main arguments against IMA are an increased operation time, initially lower blood flow, higher rates of reoperation for bleeding and more perioperative complications. In this study we investigated use of the IMA in patients with poor left ventricular function (LVEF < 40%) compared to exclusively veingraft bypass surgery. 137 patients (105 m/32 f) suffering from coronary artery disease with reduced LVEF (12-40%) were randomized in the study. 67 patients received exclusively vein grafts (group I), 70 patients routinely obtained an IMA graft. Criteria used for evaluation of IMA graft were operation time, postoperative bleeding, need for catecholamines, requirement of intensive care, perioperative myocardial infarction and mortality. The number of distal anastomoses in each group was 3.1 (2-5). The operation time varied in compliance with the number of distal anastomoses, but there were no significant differences between both groups. Postoperative bleeding until the second postoperative day was 905 ml in group II versus 569 ml in group I; the difference was significant (p < 0.05). The need of catecholamines after operation and hemodynamic parameters were comparable in both groups, there were no significant differences. Intensive care was required for a mean of 1.6 days in both groups, postoperative ventilation was 5.8 hours in group I versus 7.9 hours in group II, differences not significant. Ischemia or myocardial infarction could be demonstrated in 2 patients of group I (3%) versus 4 patients of group II (5.7%). The differences between the groups were not significant. Cardiac low output syndromes without sights of myocardial infarction were apparent in 9 patients of group I (13.5%) versus 2 patients of group II (2.9%), this difference being significant (p < 0.05). Mortality after operation in both groups was higher than in patients with normal ventricular function, however the differences between the evaluated groups were not significant (5.9% in group I versus 4.3% in group II). Summarizing the above it can be concluded that patients with poor left ventricular function are at a higher risk when subjected to bypass operation; the use of IMA did not show any disadvantages in comparison to exclusively veingraft surgery, except of a higher perioperative bleeding risk. Due to better long term results IMA should be used routinely also in bypass-patients with poor left ventricular function.