Evaluation of the MMI Symani® robotic microsurgical system for coronary-bypass anastomoses in a cadaveric porcine model.

The MMI Symani® is a recently approved robotic microsurgical system for surgical procedures in adults. The system enables the surgeon to create microanastomoses. Clinical applications so far include lymphatic vessels surgery and the creation of special flap plastics. The use of the system in coronary arteries has not yet been assessed. The aim of this preclinical study was to evaluate the applicability of the Symani® surgical system in the creation of coronary anastomoses a cadaveric porcine model. A total of 12 anastomoses were performed by three senior cardiovascular surgeons on the left main coronary artery of three porcine hearts. Artificial bypasses (diameter 1 mm) were performed to the left main trunk. The anastomoses were performed with the Symani® surgical system. Evaluation included procedure times and anastomosis leakage. All anastomoses could be successfully performed. The procedure time decreased due to the learning curve between the first anastomosis 47:28 ± 5:30 min and the last anastomosis 22:37 ± 3:25 min. The final evaluation of the anastomoses showed excellent results with low leakage. The quality of the anastomosis also improved in relation to the increasing learning curve. The Symani® surgical system could be used to create coronary anastomoses in an acceptable time frame and without technical failures. Hence, the system appears feasible for conventional coronary surgery. Further studies in animal models are mandatory prior to clinical application.

Case Report: The woman with the big heart-an imaging-guided attempt of surgical reduction.

In a female patient with acute cardiac decompensation, an auxiliary finding of a giant left atrium emerged. The surgical therapy of the atrial reduction, in addition to a mitral valve replacement and a coronary artery bypass grafting, is hereby presented.

Long-term follow-up of patients with complex coronary artery disease treated with minimally invasive direct coronary artery bypass.

BACKGROUND: Patients with complex coronary artery disease (CAD) may benefit from surgical myocardial revascularization but weighing the risk of peri-operative complications against the expected merit is difficult. Minimally invasive direct artery bypass (MIDCAB) procedures are less invasive, provide the prognostic advantage of operative revascularization of the left anterior descending artery and may be integrated in hybrid strategies. Herein, the outcomes between patients with coronary 1-vessel disease (1-VD) and patients with 2-VD and 3-VD after MIDCAB procedures were compared in this single-center study. METHODS: Between 1998 and 2018, 1363 patients underwent MIDCAB at the documented institution. 628 (46.1%) patients had 1-VD, 434 (31.9%) patients 2-VD and 300 (22.0%) patients suffered from 3-VD. Data of patients with 2-VD, and 3-VD were pooled as multi-VD (MVD). RESULTS: Patients with MVD were older (66.2 ± 10.9 vs. 62.9 ± 11.2 years; p < 0.001) and presented with a higher EuroScore II (2.10 [0.4; 34.2] vs. 1.2 [0.4; 12.1]; p < 0.001). Procedure time was longer in MVD patients (131.1 ± 50.3 min vs. 122.2 ± 34.5 min; p < 0.001). Post-operatively, MVD patients had a higher stroke rate (17 [2.3%] vs. 4 [0.6%]; p = 0.014). No difference in 30-day mortality was observed (12 [1.6%] vs. 4 [0.6%]; p = 0.128). Survival after 15 years was significantly lower in MVD patients (p < 0.01). Hybrid procedures were planned in 295 (40.2%) patients with MVD and realized in 183 (61.2%) cases. MVD patients with incomplete hybrid procedures had a significantly decreased long-term survival compared to cases with complete revascularization (p < 0.01). CONCLUSIONS: Minimally invasive direct coronary artery bypass procedures are low-risk surgical procedures. If hybrid procedures have been planned, completion of revascularization should be a major goal.

Robot-Assisted Surgery of an Iliac Artery Aneurysm: A Case Report.

Robot-assisted surgery has not yet been able to establish itself for vascular surgery. However, the preconditions for robot-assisted vascular interventions have changed fundamentally over the past years because of technological advances and extensive experience in other surgical disciplines. Hence, we describe a robot-assisted repair of an iliac artery aneurysm using a late-generation robotic platform. A 63-year-old male patient was diagnosed with an asymptomatic 30 mm aneurysm of the right common iliac artery. The operation was performed with the Da Vinci Xi system (Intuitive Surgical, Inc., Sunnyvale, CA, USA) using a direct transperitoneal approach to repair the aneurysm by interposition of a Dacron vascular prothesis. The total operating duration was 304 minutes without perioperative need for blood transfusion. The patient was discharged on the eighth postoperative day after an uneventful postoperative course. The case presented shows that robot-assisted surgery in the iliac axis can be performed safely with reasonable operating times.

Robotic-assisted abdominal aortic surgery: evidence and techniques.

In various disciplines, robotic-assisted surgery is a well-proven routine procedure, but have never been established in vascular surgery so far. This review summarizes the results to date of robotic-assisted abdominal aortic surgery (RAAS) in the treatment of aorto-iliac occlusive disease (AIOD) and abdominal aortic aneurysm (AAA). Web-based literature search of robotic-assisted surgical procedures on the abdominal aorta and iliac arteries between 1990 and 2020 including the Cochrane Library, OVID Medline, Embase, and PubMed medical databases. All studies conducting Robotic-assisted surgery were included in the quantitative analysis regarding operative and cross-clamping times, conversion rates, mortality and morbidity within the first 30 days, and in-hospital stay. Case reports and case studies (< 5 patients) were not included. Twenty-four studies were deemed thematically eligible for inclusion; after exclusion of duplicate publications, nine met the inclusion criteria for further analysis. A total of 850 patients who had either abdominal aortic aneurysm or aorto-iliac occlusive disease underwent RAAS. One study of abdominal aortic aneurysm, three of aorto-iliac occlusive disease, and five studies of both disease entities were analyzed quantitatively. For AAA, conversion rates ranged from 13.1 to 20% and perioperative mortality ranged from 0 to 1.6% with in-hospital stay of 7 days. For aorto-iliac occlusive disease, conversion rates ranged from 0 to 20%, and perioperative mortality ranged from 0 to 3.6% with in-hospital stay of 5-8 days. RAAS has been shown to be technically feasible with acceptable short-term outcomes and questionable benefits in terms of in-hospital stay and complication rates. RAAS is currently considered only an outsider procedure. Randomized-controlled trials are indispensable for regular use in vascular surgery as well as a clear approval situation for the vascular sector.

Repair of the descending thoracic aorta using minimally invasive endoscopic Robot-assisted surgery: a feasibility study with the DaVinci XI system in a cadaver model.

Development of minimally invasive techniques has led to the clinical routine application of Robot-assisted surgery. Here, we demonstrate for the first time Robotic-assisted surgery (DaVinci XI) of the descending thoracic aorta in a Thiel cadaver model and discuss its potential value in the endovascular era.

Minimally Invasive Direct Coronary Artery Bypass in High-Risk Patients with Multivessel Disease.

BACKGROUND: High-risk patients with multivessel disease (MVD) including a complex stenosis of the left anterior descending coronary may not be ideal candidates for guideline compliant therapy by coronary artery bypass grafting (CABG) regarding invasiveness and perioperative complications. However, they may benefit from minimally invasive direct coronary artery bypass (MIDCAB) grafting and hybrid revascularization (HCR). METHODS: A logistic European system for cardiac operative risk evaluation score (logES) >10% defined high risk. In high-risk patients with MVD undergoing MIDCAB or HCR, the incidence of major adverse cardiac and cerebrovascular events (MACCEs) after 30 days and during midterm follow-up was evaluated. RESULTS: Out of 1,250 patients undergoing MIDCAB at our institution between 1998 and 2015, 78 patients (logES: 18.5%; age, 76.7 ± 8.6 years) met the inclusion criteria. During the first 30 days, mortality and rate of MACCE were 9.0%; early mortality was two-fold overestimated by logES. Complete revascularization as scheduled was finally achieved in 64 patients (82.1%). Median follow-up time reached 3.4 (1.2-6.5) years with a median survival time of 4.7 years. Survival after 1, 3, and 5 years was 77, 62, and 48%. CONCLUSION: In high-risk patients with MVD, MIDCAB is associated with acceptable early outcome which is better than predicted by logES. Taking the high-risk profile into consideration, midterm follow-up showed satisfying results, although scheduled HCR was not realized in a relevant proportion. In selected cases of MVD, MIDCAB presents an acceptable alternative for high-risk patients.

Is total arch replacement associated with an increased risk after acute type A dissection?

BACKGROUND: The surgical strategy for acute type A aortic dissection (AADA) usually consists of reconstruction of the tear-lesion in the affected part of the ascending aorta. The optimal strategy either to replace the ascending aorta (AAR) or to replace the ascending aorta and the total aortic arch (TAAR) is still under debate. Our study compares the 30-day mortality between AAR and TAAR in AADA surgery. METHODS: In this retrospective observational study, we analysed a total patient cohort of 339 patients who underwent surgery for AADA from January 2001 until December 2016. A propensity score-matched analysis between the AAR- and the TAAR-group with 43 patients for each subgroup was subsequently carried out. A multivariable analysis was performed to identify risk-factors for the 30-d-mortality. The 30-day mortality was defined as the primary end-point and long-term survival was the secondary endpoint. RESULTS: In 292 (86.1%) patients AAR and in 47 (13.9%) patients TAAR was performed for emergent AADA. Patients were older (P=0.049) in the AAR group. The median log Euro-SCORE was 25.5% (12.7; 41.7) for AAR and 19.7% (11.7; 32.2) for the TAAR patient cohort (P=0.12). Operative time, cardiopulmonary bypass- (CPB), cross-clamp- and ischemic time were significantly longer in the TAAR group (P<0.001). The overall 30-day mortality-rate was 17.7% (n=60) but was not significantly different between the two groups (P=0.27). Forty-nine (16.8%) patients died in the AAR and 11 patients (23.4%) in the TAAR group. After propensity-score matching, no difference in mortality was seen between the subgroups as well (P=0.44). Multivariable analysis identified the Euro-SCORE, long operation-time, postoperative dialysis and arrhythmia and administration of red blood cell concentrates as risk factors for 30-day mortality, but not for TAAR versus AAR. CONCLUSIONS: The therapeutic goal in AADA surgery should be the complete restoration of the aorta to avoid further long-term complications and re-operations. Though 30-day mortality and postoperative co-morbidity for AAR are comparable to those in TAAR after treatment of AADA in our analysis, decision-making for the surgical strategy should weigh the operative risk of TAAR against the long-term outcome.

Sex-specific risk factors for early mortality and survival after surgery of acute aortic dissection type a: a retrospective observational study.

BACKGROUND: Although gender-related disparities in cardiovascular surgery have been investigated extensively in the past decades, knowledge about the impact of gender on outcomes after surgery for acute aortic dissection type A (AADA) is sparse. This study investigated the impact of gender on early morbidity and mortality and follow-up outcome in patients after surgery for AADA and to analyze gender-related risk factors for 30-day mortality. METHODS: This retrospective study included 368 consecutive patients (male 65.8% vs. female 34.2%) undergoing surgery for AADA between 2001 and 2016 at our department. Survival was estimated by Kaplan-Meier curves. Risk factors for 30-day mortality were assessed by multivariable logistic regression and interaction analysis. RESULTS: Women were older (70.7 years vs. 60.6 years; p <  0.001) and showed a higher logistic EuroSCORE I (31.0% vs. 19.7%, p <  0.001). In the male group, a higher portion of smokers (27.6% vs. 16.0%, p = 0.015) and intraoperatively, more complex procedures and longer cardiopulmonary bypass (CPB) (171 min vs. 149 min, p = 0.001) and cross-clamping times (94 min vs. 85 min, p = 0.018) occurred. 30-day mortality was 19.0% in the female and 16.5% in the male group (p = 0.545). Predictive for 30-day mortality in both genders was intraoperative blood transfusion, while in the female group chronic obstructive pulmonary disease (COPD), peripheral arterial disease and preoperative intubation were predictive. Preoperative cardiopulmonary resuscitation and duration of CPB time were predictors only in males. Averaged follow-up time was 5.2 years and survival did not differ between genders, even if it was stratified by age over 70 years. CONCLUSIONS: This analysis demonstrated a similar and satisfactory survival in both genders after surgical treatment of AADA. Women and men differed significantly in age, unadjusted and adjusted risk factors and complexity of surgical treatment, but gender itself was no risk factor for mortality. These results suggest that the decision-making for surgical treatment should not depend on gender, but that accounting for sex-specific risk factors rather than common risk factors may help to improve the outcome in both genders.

Sex-specific outcome after minimally invasive direct coronary artery bypass for single-vessel disease.

OBJECTIVES: Female gender is reported as an independent risk factor for a poor outcome after coronary artery bypass grafting. We analysed the influence of gender on surgical outcome in patients with single-vessel disease undergoing minimally invasive direct coronary artery bypass (MIDCAB). METHODS: From January 1998 to December 2016, a total of 607 consecutive patients with single-vessel disease (31.9% women) underwent MIDCAB at our institution. Major adverse cardiac and cerebrovascular events (MACCE) were recorded during a median follow-up period of 8.0 years. Survival time was estimated for all patients and after applying propensity score matching (138 women vs 138 men). Multivariable Cox regression analysis identified risk factors predicting a long-term mortality rate. RESULTS: In women, a longer surgical time (125 vs 113 min; P < 0.001) and a higher transfusion rate were recorded (13.0% vs 5.1%; P = 0.001) with similar rates of in-hospital deaths (1.0% vs 0.5%; P = 0.60) and MACCE (1.5% vs 0.7%; P = 0.39). Survival and MACCE-free survival during the follow-up period did not differ significantly between genders (P = 1.0, P = 0.36). Survival and MACCE-free survival rates after 5 years were 94% and 90% in women compared to 91% and 86% in men. Propensity score matching demonstrated improved long-term survival rates in women (P = 0.029). Insulin-dependent diabetes mellitus, postoperative atrial fibrillation and prolonged intensive care unit stay were associated with long-term deaths for both genders, whereas obesity, former myocardial infarction and preoperative atrial fibrillation were significant risk factors in men. CONCLUSIONS: Female patients showed no adverse outcomes after MIDCAB, although risk factors were gender-specific. Overall, MIDCAB demonstrated excellent short- and long-term results as a treatment for single-vessel disease in both genders.

Prevention of surgical site sternal infections in cardiac surgery: a two-centre prospective randomized controlled study.

OBJECTIVES: Surgical site infection (SSI) of the sternum is a devastating complication in cardiac surgery. The aim of this prospective randomized controlled two-centre clinical study was to compare the use of a gentamicin-collagen sponge (Genta-Coll® resorb) and of a cyanoacrylate-based microbial skin sealant (InteguSeal®) on the SSI rate of the sternum. METHODS: We analysed data from 996 consecutive patients following isolated coronary artery bypass grafting between 2012 and 2014. The patients were randomized into three groups: standard group (S-group), Genta-Coll group (G-group) and InteguSeal group (I-group). The primary study end-point was to analyse the incidence of superficial and deep sternal SSI. The secondary study end-point was to determine independent risk factors for an increased SSI rate. RESULTS: Of the 996 patients investigated, 332 patients were in S-group, 336 patients in G-group and 328 patients in I-group. The mean age was 67.7 ± 9.4 years, 18.6% were women and the overall SSI rate was 6.2% with 2.2% deep sternal wound infections. SSI rates were 8.3% (S-group), 5.4% (G-group) and 4.9% (I-group) (P 0.16). Multiple regression analysis demonstrated a preoperative body mass index (BMI) of >30 kg/m2 (P 0.047), re-thoracotomy for postoperative bleeding (P < 0.001) and sternum instability (P < 0.001) as independent predictors for an increased SSI rate. CONCLUSIONS: The application of InteguSeal® or Genta-Coll® resorb had no significant influence on the incidence of the sternal SSI rate in 996 consecutive cardiac surgery patients but demonstrated a trend towards a benefit from using these prophylactic approaches. Multiple regression analysis demonstrated a preoperative BMI of >30 kg/m2, re-thoracotomy for bleeding and sternum instability as independent predictors for an increased sternal SSI rate.

Impact of Gender on Outcome in Octogenarians after Coronary Artery Bypass Grafting.

Background Increasing life expectancy makes cardiac surgery in octogenarians not very uncommon. In this study, the impact of gender on outcome of octogenarians after coronary artery bypass grafting (CABG) was assessed. Materials and Methods We retrospectively studied 485 octogenarians (176 females: mean age 82.4 ± 2.2 years vs. 306 males: mean age 82.2 ± 2.4 years) who underwent isolated CABG using extracorporeal circulation between January 2005 and December 2012. Results No significant differences were noted between both gender groups with regard to preoperative risk factors. At baseline, the groups differed significantly with respect to mean logistic European System for Cardiac Operative Risk Evaluation (EuroSCORE) (women: 22.3 ± 17.4% vs. men: 17.5 ± 13.3%; p < 0.001). Likewise, EuroSCORE II differs significantly between women and men in our cohort (women: 16.7 ± 11.9% vs. men: 13.9 ± 10.7%; p = 0.008). Intraoperatively, the number of distal anastomoses (3.1 ± 0.9 vs. 3.2 ± 0.8), the mean extracorporeal circulation time (99 ± 31 vs. 102 ± 29 minutes), and the mean aortic cross-clamp time (63 ± 31 vs. 60 ± 19 minutes) were similar in both groups. Postoperatively, no significant differences in complications and major morbidity were observed between the groups. The 30-day mortality (women 8.0 vs. men 9.7%; p = 0.62) were without statistical significance between the groups. Conclusion Outcome of octogenarians after CABG resulted in acceptable mortality. Female gender was not associated with increased risks for morbidity and mortality after surgery. Satisfactory outcomes encourage the offering of surgery in octogenarians.

Short- and long-term follow-up after minimally invasive direct coronary artery bypass in octogenarians.

OBJECTIVES: Demographic changes lead to a rising incidence of octogenarians undergoing surgical revascularization of coronary artery disease. Minimally invasive direct coronary artery bypass (MIDCAB) represents a surgical treatment with reduced trauma and without the use of cardiopulmonary bypass. The aim of this study was to evaluate short- and long-term outcomes after MIDCAB in octogenarians. METHODS: Between 1998 and 2012, 1060 patients underwent MIDCAB at our department. Among them, 72 patients (6.8%) were older than 80 years at the time of operation. Incidence of major adverse cardiac and cerebrovascular events (MACCEs) was compared between octogenarians [median age 82 (81; 85) years, 63.9% male] and younger MIDCAB patients [median age 64 (56; 70) years, 70.7% male] after 30 days and during follow-up. The impact of demographics and preoperative comorbidities on mortality during follow-up was analysed. RESULTS: At baseline, the elderly group presented with a statistically significant higher logistic EuroSCORE I (9.2 vs 2.2%, P < 0.001). Within 30 days, octogenarians showed a mortality rate of 5.6% (younger patients 0.8%, P = 0.006) and an MACCE rate of 5.6% (younger patients 1.3%, P = 0.024). The median follow-up time of 30-day survivors was 5.5 (2.9; 7.6) years and follow-up completeness reached 96.9%. In the elderly group, 1-, 3- and 5-year survival rates were 89, 78 and 63% in comparison with 97, 94 and 90% in the younger group (P < 0.001), respectively. The estimated median survival time in octogenarians was 6.7 (CI 4.854; 8.629) years. Logistic regression showed preoperative renal impairment, peripheral arterial occlusive disease and pulmonary hypertension to have a stronger impact on mortality during follow-up than age above 80 years. CONCLUSIONS: MIDCAB represents a safe treatment option in octogenarians and is associated with a good perioperative outcome and satisfying long-term results in octogenarians.

Transatrial Cannulation of the Left Ventricle for Acute Type A Aortic Dissection: A 5-Year Experience.

BACKGROUND: Acute type A aortic dissection (AAD) is a life-threatening disorder with a high rate of mortality and complications. All cannulation techniques currently used to establish arterial flow for cardiopulmonary bypass are associated with a considerable risk of organ malperfusion, stroke, or access site trauma. Here, we report the impact of transatrial cannulation of the left ventricle on patient outcome after surgical treatment of AAD. METHODS: Between 2010 and 2013, 46 patients underwent emergency surgery for AAD using transatrial cannulation of the left ventricle. Their outcome was retrospectively compared with that of 73 age- and sex-matched patients operated on for AAD between 2006 and 2010 before introduction of the new technique. RESULTS: No differences concerning preoperative details were found. Arterial flow before 2010 was established after preparation of the femoral artery in 46 patients (63.0%) or by direct cannulation of the ascending aorta in 27 patients (37.0%). Operation times were significantly lower in the transatrial cannulation group (271.2 ± 75.4 versus 308.3 ± 78.2; p = 0.02). Postoperatively, we observed a significantly reduced stroke rate in the group with transatrial cannulation (6.5% versus 26.5%; p = 0.007) and a decreased rate of acute renal failure (20.0% versus 32.4%; p = 0.003). Intraoperative mortality (0% versus 6.8%; p = 0.16), 30-day mortality (8.9% versus 10.3%; p = 1.00), and mortality during follow-up (9.8% versus 34.4%; p = 0.08) did not differ. However, overall mortality was significantly lower in the group after transatrial cannulation (17.7% versus 45.2%; p = 0.003). CONCLUSIONS: In patients undergoing surgery for AAD, transatrial cannulation of the left ventricle proved to be a safe and easy cannulation method that significantly reduced postoperative complications.

Off-pump coronary artery bypass prevents visceral organ damage.

OBJECTIVES: Visceral malperfusion after coronary artery bypass grafting (CABG) results in high morbidity and mortality. This study was designed to evaluate the effect of CABG performed by surgical techniques on visceral perfusion and function. METHODS: Pigs (n = 28) were studied in four groups: I. Sham; II. Off-pump coronary artery bypass grafting (OPCAB): 1 h stabilizer with 40 min intracoronary shunt; III. Extracorporeal circulation (ECC): 1 h ECC with 40 min aortic cross-clamping and cardioplegic arrest; IV. Impella: 1 h left ventricular blood-pump support and stabilizer with 40 min intracoronary shunt. A left internal mammary to left anterior descending coronary artery bypass was performed in Groups II-IV. All animals were observed for a further 240 min. During the experiment haemodynamics, creatinine clearance, intestinal fatty acid binding protein (iFABP), pancreatic (lipase and amylase) and liver enzymes (α-glutathione s-transferase, glutamate-oxaloacetate transaminase (GOT), gamma-glutamyl transferase (GGT), glutamate dehydrogenase and glutamate-pyruvate transaminase (GPT)) were measured. Visceral perfusion (VP) was assessed in both kidneys, intestine, pancreas, liver and spleen with 15 µm fluorescent microspheres. RESULTS: During OPCAB surgery, VP decreased slightly. Renal functional parameters, iFABP, pancreatic and liver enzymes remained unchanged. ECC and Impella led to significantly reduced renal, pancreatic and intestinal blood flow (P < 0.05). Creatinine clearance, pancreatic and liver (GPT, GGT) enzymes were significantly decreased only after ECC (P < 0.05). ECC and Impella resulted in a significantly increased iFABP level (P < 0.05). GOT was elevated significantly after surgery in Groups II, III and IV (P < 0.05). CONCLUSIONS: CABG with ECC or Impella leads to impaired visceral blood flow and function. OPCAB minimizes these procedure associated alterations.

Minimally invasive direct coronary artery bypass in a child with an occlusion of left main coronary artery after arterial switch operation.

We present a case of a 13-year old girl experiencing recurring angina pectoris due to an occlusion of the left main coronary artery after arterial switch operation in infancy. To avoid a repeat sternotomy and the use of cardiopulmonary bypass, the patient underwent uncomplicated operative myocardial revascularization in the minimally invasive direct coronary artery bypass (MIDCAB) technique.

Highly flexible nitinol mesh to encase aortocoronary saphenous vein grafts: first clinical experiences and angiographic results nine months postoperatively.

Saphenous vein graft patency is frequently limited by degeneration. Experimental studies have indicated that rigid external support of venous grafts by a flexible, tubular nitinol mesh may improve graft patency. The study presented was part of a prospective, randomized, multicenter first-in-man trial investigating the safety and effectiveness of nitinol-supported venous grafts in coronary artery bypass graft (CABG) surgery. From our clinic, 25 subjects with multivessel coronary artery disease requiring saphenous vein graft CABG of the right coronary artery (RCA) and the circumflex artery were entered into the trial. Subjects were randomized to receive a mesh-supported graft on one of these arteries; the other vessel received an untreated vein graft. Graft patency was assessed by coronary angiography nine months after surgery. The implantation of mesh grafts was simple and safe. In 10 cases, a nitinol mesh-supported venous graft was anastomosed to the circumflex artery and in 15 cases to the RCA. All patients survived the observation period. A total of 72% of the patients underwent control coronary angiography. The patency rate of mesh-supported grafts was 27.8% nine months postoperatively. Conventional vein grafts showed an 85.7% patency, and arterial grafts had a 100% patency. No complications directly related to the implantation of mesh-supported grafts were observed. The promising experimental results of mesh-supported venous grafts could not be reproduced in the study presented. A critical item seems to be correct selection of nitinol mesh diameter, the anastomotic method and fixation of the mesh tube to the venous graft.

Does patient-prosthesis mismatch influence the results of combined aortic valve replacement and coronary bypass grafting?

BACKGROUND: Combined aortic valve replacement and coronary revascularisation is becoming more frequent. Patient-prosthesis mismatch (PPM) as an additional risk factor may potentially affect the early and late outcome. AIM: To evaluate the impact of PPM on early and mid-term clinical results including quality of life in patients undergoing combined surgical treatment of coronary artery disease and aortic valve defects. METHODS: Medical records of 309 consecutive patients referred for combined surgery were reviewed. Patients were divided into three groups according to the presence of moderate or severe PPM (defined by aortic valve effective orifice area index in the range 0.85-0.65 cm2/m2 and smaller than 0.65 cm2/m2, respectively) or absence of PPM. The demographic and perioperative data, and early and late survival, as well as quality of life (SF-36) were analysed. RESULTS: The presence of severe PPM was found in 51 (16.5%) patients, whereas moderate PPM--in 153 (49.5%) patients. Patients from both PPM groups were significantly older than those without PPM. Subjects with severe PPM had higher weight and body mass index. They frequently had dyslipidaemia and both PPM groups received a biological valve more often than patients without PPM (94.1 and 77.1 vs. 19.1%, p<0.0001). There was no significant difference between all groups regarding early or late mortality. Advanced age, renal insufficiency and arrhythmia were predictors of early death. Late survival was determined only by number of postoperative complications in a Cox regression model. There was no difference in any components of the SF-36 survey between all groups. CONCLUSIONS: PPM is a frequent phenomenon in older patients requiring aortic valve replacement and revascularisation. Severe PPM occurs rarely, predominantly in obese patients. However, its presence does not affect early and late survival or quality of life.

Measurement of blood flow index during antegrade selective cerebral perfusion with near-infrared spectroscopy in newborn piglets.

BACKGROUND: Neonates with complex congenital heart defects have traditionally undergone surgery during deep hypothermic cardiac arrest (HCA). Selective cerebral perfusion (SCP) is thought to minimize ischemic brain injury by providing adequate cerebral blood flow. We investigated SCP with different flow rates compared with HCA with respect to cerebral perfusion and tissue oxygenation as assessed by near-infrared spectroscopy. METHODS: Twenty-one piglets were placed on cardiopulmonary bypass at 18 degrees C, then underwent either HCA or SCP at 25 or 50 mL x kg(-1) x min(-1) for 90 min. The blood flow index (BFI) derived by indocyanine green and tissue oxygen index (TOI) were determined by near-infrared spectroscopy. Mean cerebral blood flow velocity (FV(mean)) was recorded by transcranial Doppler ultrasound. RESULTS: Both BFI and FV(mean) increased significantly (126 +/- 27% of baseline; 19 +/- 2 cm/s) in the SCP 50 group compared with HCA (no flow) and SCP 25 (65 +/- 24%; 10 +/- 1 cm/s), respectively. TOI increased in the SCP 50 group compared with baseline (74 +/- 4% vs 65 +/- 4%), and was higher compared with HCA (52 +/- 2%) and SCP 25 (59 +/- 2%). Intracranial pressure increased nonsignificantly compared with baseline in the SCP 50 group. CONCLUSIONS: Both BFI and FV(mean) suggested increased cerebral perfusion in the SCP 50 group compared with the HCA and SCP 25 groups. TOI was significantly higher in both the SCP 25 and SCP 50 groups compared with HCA. SCP at 25 mL x kg(-1) x min(-1) may be most appropriate for cerebral protection.

Durability of bioprosthetic cardiac valves.

INTRODUCTION: The choice of type of heart valve prosthesis is determined by the patient's age since bioprostheses have a limited lifespan. This article reviews current recommendations and the literature on cardiac valve replacement. METHODS: Selective literature search in Medline/PubMed back to 1996 and review of current national and international recommendations from specialist societies. RESULTS: The recommendations guiding the type of heart valve replacement have been revised in recent years. Of particular interest are the new generation of biological prostheses with extended durability, a growing use of stentless bioprostheses, a decrease in mortality of reoperation and an increase in life expectancy. Comorbidities such as chronic renal insufficiency or chronic atrial fibrillation are no longer contraindications to bioprosthesis. The number of heart valve replacements in recent years rose despite a concomitant increase in valve repairs. Aortic valves are being increasingly replaced by bioprostheses. DISCUSSION: The choice of heart valve prosthesis should be tailored to each patient taking into account the patient's age, life expectancy, comorbidities, and life style. Different decisions may be made now than those based on earlier recommendations resulting in an individualized treatment, in patients over the age of 65 or 70.