Long-term clinical outcome of the symmetry aortic connector system in off-pump coronary artery bypass grafting.

BACKGROUND: Several short-term and midterm follow-up studies of the Symmetry aortic connector system showed controversial results. The objective of the present study was assessing the long-term clinical outcome of patients operated with the Symmetry device and to compare the results with hand-sewn control patients. METHODS: A retrospective case-control study of 156 (46 cases, 110 controls) consecutive patients, that underwent off-pump coronary revascularization, between January 2001 and December 2004, was conducted. Study endpoints were all-cause mortality, coronary reintervention and postoperative stroke. RESULTS: There was no difference in survival between cases and controls (89.1 vs. 82.4%, p = 0.27) after 8 years of follow-up. No significant difference could be detected between cases and controls with respect to overall long-term coronary reintervention free survival (82.6 vs. 88.9%, p = 0.41) and freedom from coronary reintervention due to proximal vein graft failure (91.3 vs. 96.3%, p = 0.24). The use of Symmetry device could not be identified as independent risk-factor of coronary reintervention due to proximal vein graft failure (p = 0.25). Furthermore, postoperative stroke rates were comparable between cases and controls (0.0 vs. 0.9%, p = 1.00). CONCLUSION: This study suggests that the use of the Symmetry Bypass Connector was not associated with adverse outcome in terms of overall survival, long-term coronary reintervention free survival, freedom from reintervention due to proximal vein graft failure and postoperative stroke.

Predictive value of the additive and logistic EuroSCOREs in patients undergoing aortic valve replacement.

OBJECTIVES: The purpose of this study was to evaluate the accuracy of the additive and logistic EuroSCOREs in predicting the operative mortality in patients undergoing aortic valve replacement (AVR) with or without coronary artery bypass graft (CABG) surgery. DESIGN: This was a retrospective analysis of prospectively collected data. SETTING: This was a single-center study performed in an educational hospital. PARTICIPANTS: All patients (n = 1,885) who underwent AVR with (n = 813) or without (n = 1,072) CABG surgery between 1998 and 2007. INTERVENTIONS: AVR with or without CABG surgery. MEASUREMENTS AND MAIN RESULTS: Variable life-adjusted display curves were constructed to compare the observed operative mortality with the additive and logistic EuroSCOREs. The receiver operating characteristics (ROC) curve was used to determine the discriminatory power of the additive and logistic EuroSCOREs. Calibration between the predicted and the observed operative mortality was checked by comparing the predicted probability of the mortality with the additive and logistic EuroSCORE. In the isolated AVR group, the additive EuroSCORE was 5.8% predicted mortality and the logistic EuroSCORE was 7.2%, whereas the observed operative mortality was 3.2%. In the AVR with CABG surgery group, the additive EuroSCORE was 7.2% and the logistic EuroSCORE was 8.8%, whereas the observed operative mortality was 5.3%. ROC curve analyses showed a high discriminatory power for both EuroSCOREs in both patient groups. CONCLUSIONS: Although the additive and the logistic EuroSCOREs had good discriminatory power, they were not able to predict the actual operative mortality accurately. Both EuroSCOREs overestimated the operative mortality, especially in low-risk patients.

Thrombocytopenia after aortic valve replacement: comparison between mechanical and biological valves.

BACKGROUND AND AIM OF THE STUDY: Concerns have been recently raised regarding the postoperative decrease in platelet count after aortic valve replacement (AVR). Thus, a retrospective analysis was conducted of patients after AVR with regards to postoperative platelet count. METHODS: The data were analyzed from all patients undergoing AVR with (n = 829) or without (n = 1,230) coronary artery bypass grafting (CABG) at a single center between January 1998 and May 2009. The lowest (minimum) platelet count within the first five postoperative days was determined. RESULTS: The patients received either an ATS mechanical prosthesis (ATS; n = 401), a St. Jude Medical mechanical prosthesis (SJM; n = 791), a Carpentier-Edwards Perimount bioprosthesis (CEP; n = 618), a Medtronic Freestyle stentless bioprosthesis (FRE; n = 213), or a Sorin Freedom Solo stentless bioprosthesis (SFS; n = 36). By using a multivariate linear regression model, the following independent risk factors for a lower postoperative platelet count were revealed: age, body surface area, active endocarditis, preoperative platelet count, duration of extracorporeal circulation, number of grafts, valve size, and units of transfused fresh-frozen plasma and red blood cells. On entering the type of prosthesis into the multivariate linear regression analysis, together with the other risk factors, patients with CEP and FRE valve prostheses had a lower minimum postoperative platelet count than those with mechanical prostheses (ATS and SJM). CONCLUSION: Patients undergoing AVR with the Carpentier-Edwards Perimount bioprosthesis or a Medtronic Freestyle stentless bioprosthesis had a lower minimum platelet count within the first five postoperative days, compared to patients receiving ATS and St. Jude Medical mechanical prostheses. No differences were identified between the Sorin Freedom Solo and all other valve prostheses.

Safety of the extended radial artery conduit in performing complete arterial revascularization.

PURPOSE: We have developed a technique to elongate the radial artery (RA) with the distal segment of the left internal thoracic artery. This study investigated the safety and durability of this extended conduit compared with the composite Y-grafts. METHODS: From January 1998 through December 2010, 750 patients underwent complete arterial revascularization with the use of the left internal thoracic artery (LITA) and RA. Out of these patients, 362 patients were operated on with the use of either RA-LITA extension conduit (n = 103), or a composite LITA-RA Y-graft (n = 259) and were included in this study. Cox regression analyses and Kaplan-Meyer survival curves were used to identify the predictive value of the RA-LITA extension technique on both survival and incidence of re-intervention. RESULTS: Cox regression analysis showed that the use of RA-LITA extension conduit was not a significant predictor of re-intervention (p = 0.600) or total survival (p = 0.930).Kaplan-meier curves showed no significant difference between the two groups concerning total survival and re-intervention-free survival (p = 0.600). CONCLUSIONS: Our alternative technique of extending the RA with the distal segment of the LITA is a safe alternative for patients undergoing total arterial revascularization. The long-term survival and incidence of re-intervention is comparable with the composite LITA-RA Y-grafts.

Distal anastomotic patency of the Cardica C-PORT(R) xA system versus the hand-sewn technique: a prospective randomized controlled study in patients undergoing coronary artery bypass grafting.

OBJECTIVES: The C-Port® Distal Anastomosis Systems (Cardica, Inc., Redwood City, CA, USA) demonstrated favourable results in feasibility trials. However, distal vein anastomoses created with the C-Port® or C-Port xA® system have never been compared with hand-sewn distal vein anastomoses. The objective of this study was to compare distal end-to-side anastomoses facilitated with the C-Port xA® System with the traditional hand-sewn method. METHODS: This single-centre prospective randomized controlled study comprised 71 patients (device group n = 35, control group n = 36) who underwent primary elective coronary artery bypass grafting between June 2008 and April 2011. The primary study end-point was 12-month distal anastomotic patency, which was assessed with prospective ECG-gated 256-multislice computed tomographic coronary angiography using a step-and-shoot scanning protocol. For the primary end-point, a per-protocol analysis was used. RESULTS: In the device group, four (11%) anastomoses were converted to hand-sewn anastomoses, and additional stitches to achieve haemostasis were necessary in 22 (76%) patients. There was no hospital mortality in either group. During the 12-month follow-up, a single death occurred in the Device group and was unrelated to the device. Twenty-nine patients in the device group and 32 in the control group completed 12-month CT coronary angiography. The overall patency of 160 studied distal vein graft anastomoses was 93%. Comparison of the end-to-side target anastomosis showed 12-month patencies of 86 and 88% in the device group and the control group, respectively. CONCLUSIONS: According to these preliminary results and despite the limited number of patients, the use of the C-Port xA® System is safe enough to perform distal end-to-side vein graft anastomosis, with respect to 12-month end-to-side distal venous anastomotic patency. Although there are some technical challenges with this device, the incidence of complications is comparable to the traditional hand-sewn technique.

Does new-onset postoperative atrial fibrillation after coronary artery bypass grafting affect postoperative quality of life?

OBJECTIVES: New-onset postoperative atrial fibrillation (POAF) is a common complication after cardiac surgery. We investigated the effect of POAF on quality of life after coronary artery bypass grafting. METHODS: All patients who underwent nonemergency coronary artery bypass grafting between March 2009 and January 2011 were requested to complete a Short Form-36 Health Survey before and 6 months after the procedure. Norm-based scores of 8 health status domains and 2 component summary scores were calculated. Only patients undergoing first-time coronary artery bypass grafting, with no history of atrial fibrillation, were included in the analyses. RESULTS: Of 1608 patients, 360 (22.4%) had POAF diagnosed. Twenty-eight patients died within half a year after the procedure (1.7% in the no POAF group and 1.8% in the POAF group; P = .90). After excluding these patients, data from 1580 patients were analyzed. Preoperative questionnaires were returned by 66% of the patients and postoperative questionnaires by 65%. Preoperative scores did not differ between patients with and without POAF in any subcategory (0/10). After the procedure, 4 of 10 scores were worse in the group with POAF compared to patients without POAF. Patients without POAF improved in all subcategories (10/10) after the procedure, whereas those with POAF did so in only 7 of 10. Multilinear regression showed POAF to be an independent negative predictor for improved quality of life 6 months postoperatively in 7 of 10 subcategories, including both mental and physical component summary scores. CONCLUSIONS: New-onset POAF does affect 6-month postoperative mental and physical health, possibly warranting more aggressive POAF treatment.

New-onset postoperative atrial fibrillation predicts late mortality after mitral valve surgery.

BACKGROUND: New-onset postoperative atrial fibrillation (POAF) is a common rhythm disturbance after mitral valve surgery. In this study we investigated the independent effect of POAF on early and late mortality after mitral valve surgery. METHODS: Data of patients who consecutively underwent mitral valve surgery with or without concomitant coronary or tricuspid valve surgery between January 2003 and June 2010 were prospectively collected. The study included 856 patients with preoperative sinus rhythm, and no history of atrial fibrillation. Logistic regression and Cox proportional hazard analyses were performed to investigate independent predictors of early and late mortality. Propensity score adjustment was performed to reduce the effect of confounders. RESULTS: The median follow-up was 3.1 years (range, 0 to 7.4 years). The POAF was documented in 361 patients (42%). Early mortality did not differ in patients with and without POAF (p = 0.93). Postoperative atrial fibrillation was not identified as predictor for early mortality. Late survival was worse in patients with POAF (log-rank, p < 0.001). Multivariate and propensity score adjusted Cox proportional hazard analyses demonstrated that POAF was an independent predictor for late mortality with hazard ratios of 2.09 and 1.61 (p = 0.001 and p = 0.033, respectively). CONCLUSIONS: Postoperative atrial fibrillation is an independent predictor for late all-cause mortality after mitral valve surgery but not for early all-cause mortality.

Sutureless mitral valve replacement with bioprostheses and Nitinol attachment rings: feasibility in acute pig experiments.

OBJECTIVE: There is a need for fast, minimally invasive sutureless replacement of mitral valves. METHODS: Unchanged FDA-approved biological valve prostheses were sutured to Nitinol attachment rings (Endosmart, Stutensee, Germany) that were covered with textile (devices). The lower flange of the device was stretched in ice water and maintained in a stretched position with stretching sutures. In 9 acute pig experiments through a limited left thoracotomy, a single suture was placed around the mitral annulus, the device was positioned, the annular suture tied, the stretching sutures retracted, and the device activated by warm saline. Position of the device, heart and valve function, coronary arteries, left ventricular outflow tract, and surrounding structures were observed with transoesophageal echocardiography, left ventricular and coronary angiograms, and pathologic examination at autopsy. RESULTS: The devices could be easily navigated to the mitral valve annulus and actuated within seconds. Three devices were placed with warm blood in the operative field and were tilted or dislocated at autopsy. In the other 6 devices, transesophageal echocardiography and left ventricular and coronary angiography demonstrated normal prosthetic valve and heart function, without valvular or para-device leakage, and with normal aortic valve and coronary arteries. At autopsy in these 6 cases, the devices were strongly fixed at the anatomic mitral valve annulus, without abnormalities of the device, heart valve prosthesis, left ventricular outflow tract, or aortic valve ostium. CONCLUSIONS: Nitinol attachments rings combined with unchanged biological valve prostheses can make fast and strong sutureless replacement of the mitral valve feasible in acute pig experiments. Applicators that constrain and release the device mechanically need to be developed.

Sutureless replacement of aortic valves with St Jude Medical mechanical valve prostheses and Nitinol attachment rings: feasibility in long-term (90-day) pig experiments.

OBJECTIVE: Nitinol attachment rings (devices) used to attach mechanical aortic valve prostheses suturelessly were studied in long-term (90 days) pig experiments. METHODS: The aortic valve was removed and replaced by a device around a St Jude Medical mechanical valve prosthesis in 10 surviving pigs. Supravalvular angiography was done at the end of the operation. No coumarin derivates were given. RESULTS: No or minimal aortic regurgitation was confirmed in all surviving pigs at the end of the operation. Total follow-up was 846 days. In 4 pigs, follow-up was shorter than 90 days (28-75 days); the other 6 pigs did reach 90 days' survival or more. Repeat angiography in 4 pigs at the end of follow-up confirmed the unchanged position of the device at the aortic annulus, without aortic regurgitation. At autopsy, in all pigs the devices proved to be well grown in at the annulus, covered with endothelium, and sometimes tissue overgrowth related to not using coumarin derivates. There was no case of para-device leakage, migration, or embolization. No damage to surrounding anatomic structures or prosthetic valves was found. CONCLUSIONS: Nitinol attachment rings can be used to replace the aortic valve suturelessly with St Jude Medical mechanical aortic valve prostheses, without para-device leakage, migration, or damage to the surrounding tissues, in long-term pig experiments during a follow-up of 90 days or more. Refraining from anticoagulation in pigs with mechanical valve prostheses can lead to tissue overgrowth of the valve prosthesis. Further studies are needed to determine long-term feasibility of this method in human beings.

Body mass index predicts new-onset atrial fibrillation after cardiac surgery.

OBJECTIVE: New-onset postoperative atrial fibrillation (POAF) after cardiac surgery is associated with increased morbidity and mortality. Since obesity is becoming increasingly prevalent, identifying body mass index (BMI) as a risk factor for POAF could be of importance. The aim of our study is to investigate the effect of BMI on POAF, independent of other risk factors. METHODS: We analyzed data of 6788 men and 2560 women who underwent coronary artery bypass grafting, valve surgery, or a combination of both, and who had no history of atrial fibrillation. Men and women were analyzed separately because risk factors of POAF were expected to be distributed unequally over both sexes. RESULTS: The independent effect of gender was analyzed in a combined model. POAF occurred in 2517/9348 (27%) of patients. Multivariate logistic regression analyses showed that BMI (odds ratio (OR) 1.03; 95% confidence interval (CI): 1.01-1.04; p<0.001 in men and OR 1.03; 95% CI: 1.02-1.05; p<0.001 in women), age (OR 1.06; 95% CI: 1.05-1.07; p<0.001 in men and OR 1.05; 95% CI: 1.04-1.06; p<0.001 in women), valve surgery compared to coronary surgery (e.g., mitral valve surgery compared to coronary artery bypass grafting: OR 3.4; 95% CI: 2.4-4.6; p<0.001 in men and OR 2.9; 95% CI: 2.0-4.3; p<0.001 in women) and male gender (OR 1.23; 95% CI: 1.09-1.38; p=0.001) were the only independent risk factors for POAF, whereas chronic obstructive pulmonary disease, hypertension, off-pump coronary artery bypass grafting, extra corporal circulation time, and transfusion of blood products were not. CONCLUSION: Body mass index, age, undergoing valve surgery and male gender, are independent risk factors for POAF.

The impact of preoperative atrial fibrillation on early and late mortality after coronary artery bypass grafting.

OBJECTIVES: There are still doubts on the effect of preoperative atrial fibrillation (AF) on early and late mortality after coronary artery bypass grafting (CABG). This retrospective study demonstrates the effects of preoperative AF on the short-term and long-term survival after CABG. METHODS: We retrospectively analysed the data of 10626 patients who underwent CABG between January 1998 and December 2007. The data of 221 patients with a history of preoperative AF (2.5%) and 8631 patients with preoperative sinus rhythm were eligible for analysis. Survival of these patient groups was compared to survival of age- and sex-matched groups of the Dutch general population. RESULTS: Mean follow-up duration was 4.6 + or - 2.9 years. Multivariate logistic regression analysis showed preoperative AF to be an independent risk factor for early mortality after CABG, with an odds ratio of 2.06 (95% confidence interval (CI): 1.08-3.95; P=0.029). Multivariate Cox proportional hazard analysis revealed that preoperative AF is an independent risk factor for late mortality after CABG, with a hazard ratio (HR) of 1.67 (95% CI: 1.21-2.31; P=0.002). Using propensity score matching, AF was also an independent risk factor for late mortality after CABG, with an HR of 2.77 (95% CI: 1.6-4.79; P<0.001). In comparison with the general Dutch population, patients with preoperative AF who undergo CABG have a worse long-term survival, while patients with preoperative sinus rhythm experience a better survival. CONCLUSIONS: Preoperative AF is an independent risk factor for early and late mortality after first-time elective CABG.

The impact of new-onset postoperative atrial fibrillation on mortality after coronary artery bypass grafting.

BACKGROUND: New-onset postoperative atrial fibrillation (POAF) is a frequent rhythm disturbance after coronary artery bypass grafting (CABG). This study investigated the independent effect of POAF on early and late mortality after isolated CABG. METHODS: Data of patients who consecutively underwent isolated CABG between January 2003 and December 2007 were prospectively collected. The analysis included 5098 patients with preoperative sinus rhythm and no history of atrial fibrillation. Logistic regression analysis for early mortality and Cox regression analysis for late mortality were performed. Propensity score matching was performed to eliminate the effect of confounders. RESULTS: Median follow-up was 2.5 years. POAF was documented in 1122 patients (22.0%). Early mortality was more frequent in POAF patients (3.1%) vs non-POAF patients (1.6%, p = 0.002), but multivariate logistic regression analysis could not identify POAF as an independent predictor of early mortality (p = 0.169). This outcome did not change after adjusting for quintiles of the propensity score of POAF (p = 0.100). Multivariate Cox proportional hazard analyses demonstrated POAF was an independent predictor of overall and late mortality with hazard ratios of 1.35 (p = 0.012 and p = 0.039, respectively). Analyses after propensity score matching showed that patients with POAF had similar hazard ratios of 1.36 for overall mortality and 1.34 for late mortality (p = 0.009 and p = 0.042, respectively). CONCLUSIONS: POAF is an independent predictor of overall and late mortality after isolated CABG but not of early mortality.

[Myocardial revascularization and radial artery: different surgical strategies and short-term results]. / Rivascolarizzazione miocardica con arteria radiale: tecniche chirurgiche a confronto e risultati a breve termine.

BACKGROUND: The radial artery is routinely used as a graft for surgical arterial myocardial revascularization. The proximal radial artery anastomosis site remains unknown. In this study, we analyzed the short-term results and the operative risk determinants after having used four different common techniques for radial artery implantation. METHODS: From January 2000 to December 2004, 571 patients underwent coronary artery bypass grafting with radial arteries. Data were analyzed for the entire population and for subgroups following the proximal radial artery anastomosis site: 140 T-graft with the mammary artery (group A), 316 free-grafts with the proximal anastomosis to the ascending aorta (group B), 55 mammary arteries in situ elongated with the radial artery (group C) and 60 radial arteries elongated with a piece of mammary artery and anastomosed to the ascending aorta (group D). RESULTS: The mean age was 53.8 +/- 7.7 years; 55.5% of patients had a previous myocardial infarction and 73% presented with a satisfactory left ventricular function. A complete arterial myocardial revascularization was achieved in 532 cases (93.2%) and 90.2% of the procedures were performed under cardiopulmonary bypass and cardioplegic arrest. The operative mortality rate was 0.9%, a postoperative myocardial infarction was diagnosed in 19 patients (3.3%), an intra-aortic balloon pump was used in 10 patients (1.7%) and a mechanical circulatory device was implanted in 2 patients. The radial artery harvesting site remained always free from complications. The proximal radial artery anastomosis site was not a determinant of early hospital mortality. Group C showed a higher risk of postoperative myocardial infarction (p = 0.09), together with female gender (p = 0.003), hypertension (p = 0.059) and a longer cardiopulmonary bypass time. CONCLUSIONS: The radial artery and the mammary artery can guarantee multiple arterial revascularization also for patients with contraindications to double mammary artery use. The four most common techniques for proximal radial artery anastomosis are not related to a higher operative risk and they can be used alternatively to reach the best surgical results.

Fast sutureless implantation of mechanical aortic valve prostheses using Nitinol attachment rings: Feasibility in acute pig experiments.

OBJECTIVE: There is a need for fast sutureless implantation of valve prostheses with a better outcome than that of current valved stents. METHODS: The suture ring of a St Jude mechanical valve prosthesis (St Jude Medical, Minneapolis, Minn) was replaced by a proprietary non-stent-based attachment ring made of Nitinol memory metal (Endosmart, Stutensee, Germany) and covered with textile. In acute pig experiments, the aortic valve was removed and the device was introduced in a temporary stretched shape and activated by removing constrainers and heating to reach its final attachment shape. RESULTS: The devices could be actuated within seconds. Echocardiography showed normal prosthetic valve and heart function. No paradevice leakage was demonstrated by supravalvular angiography. At autopsy, no abnormalities were found in the surrounding structures or valve prostheses. Pulling tests showed the strong adhesive power of Nitinol attachment rings withstanding up to 5 kg of pulling force. CONCLUSION: Nitinol memory metal attachment rings, covered with textile, around suture ring-denuded St Jude mechanical aortic valve prostheses enabled fast and strong sutureless implantation in acute pig experiments. Further studies in chronic animal models and humans are needed to determine long-term safety.

Hospital outcome after aorta-radial versus internal thoracic artery-radial artery grafts.

BACKGROUND: We researched our data to determine whether use of radial artery (RA) led to similar hospital morbidity as use of pedicled internal thoracic artery (ITA) with vein grafts. We also investigated if use of RA, different RA operative techniques, or number of inflow grafts were predictors for hospital outcome. METHOD: Retrospectively the hospital outcome of the first 512 patients with RAs (RA group) was compared with 108 matched patients with left ITA (LITA) and vein grafts (LITA control group). Two subgroups of RA operative techniques were further analyzed: 327 patients with RA directly from aorta (aorta-RA group), and 185 patients with RA from ITA, as a composite graft, (ITA-RA group). RESULTS: Hospital outcome of the RA group was similar to that of the LITA control group. When all ischemic events (IE) were grouped together, univariate analysis showed that aorta-RA group resulted in less IE than the ITA-RA group (2.1% versus 5.9%, respectively, p = 0.025). Number of inflow grafts did not influence IE. Multivariate analysis, however, did not show that technique of proximal RA anastomosis or number of inflow grafts were predictors for IE. CONCLUSIONS: Hospital outcome after the use of the RA is similar to that of LITA with vein grafts. Univariate analysis shows less IE after direct aorta-RA anastomoses, but multivariate analysis did not show that technique of proximal RA anastomosis and number of inflow grafts are important predictors for hospital outcome.