Nicolas Doll

Stroke after cardiac surgery: a risk factor analysis of 16,184 consecutive adult patients.

BACKGROUND Stroke remains a devastating complication after cardiac surgical procedures despite advances in perioperative monitoring and management. The purpose of this study was to determine the predictors of stroke in a large, contemporary cardiac surgery population. METHODS Prospective data on 16,184 consecutive patients undergoing cardiac surgery (coronary artery bypass grafting [CABG], n = 8,917; beating heart CABG, n = 1,842; aortic valve surgery, n = 1,830; mitral valve surgery, n = 708; double or triple valve surgery, n = 381; CABG and valve surgery, n = 2,506) between April 1996 and August 2001 were subjected to univariate and multivariate analysis. Stroke was defined as any new permanent (manifest stroke) or temporary neurologic deficit or deterioration (transient ischemic attack or prolonged reversible ischemic neurologic deficit) and was confirmed by computed tomography or magnetic resonance imaging whenever possible. RESULTS Overall incidence of stroke was 4.6% and varied between surgical procedures (CABG 3.8%; beating-heart CABG 1.9%; aortic valve surgery 4.8%; mitral valve surgery 8.8%; double or triple valve surgery 9.7%; CABG and valve surgery 7.4%). Of 63 patient-specific and treatment variables, 54 were found to have a significant univariate association with postoperative stroke. Multivariable analysis revealed 10 variables that were independent predictors of stroke: history of cerebrovascular disease, peripheral vascular disease, diabetes, hypertension, previous cardiac surgery, preoperative infection, urgent operation, CPB time more than 2 hours, need for intraoperative hemofiltration, and high transfusion requirement. Beating heart CABG was associated with a lower incidence of stroke in this multivariable analysis. CONCLUSIONS Identification of predictors for stroke is important for understanding the pathogenesis of this devastating complication as well as for developing preventative strategies. Although retrospective analyses can be subject to selection bias we believe beating heart CABG is associated with a lower incidence of stroke and may therefore improve patient outcomes.

Early and late outcomes of 517 consecutive adult patients treated with extracorporeal membrane oxygenation for refractory postcardiotomy cardiogenic shock

OBJECTIVE Adult postcardiotomy cardiogenic shock potentially requiring mechanical circulatory support occurs in 0.5% to 1.5% of cases. Risk factors influencing early or long-term outcome after extracorporeal membrane oxygenation implantation are not well described. METHODS Between May 1996 and May 2008, 517 adult patients received extracorporeal membrane oxygenation support for postcardiotomy cardiogenic shock. Procedures were isolated coronary artery bypass grafting (37.4%), isolated valve surgery (14.3%), coronary artery bypass grafting plus valve surgery (16.8%), thoracic organ transplantation (6.5%), and other combinations (25.0%). Fifty-four preoperative and 42 procedural risk factors concerning in-hospital mortality were evaluated by logistic regression analyses. RESULTS Mean age was 63.5 years, 71.5% were male, ejection fraction was 45.9% +/- 17.6%, logistic EuroSCORE was 21.6% +/- 20.7%. Extracorporeal membrane oxygenation was established through thoracic (60.8%) or extrathoracic (39.2%) cannulation. Extracorporeal membrane oxygenation support was 3.28 +/- 2.85 days. Intra-aortic balloon pumps were implanted in 74.1%. Weaning from extracorporeal membrane oxygenation was successful for 63.3%, and 24.8% were discharged. Cerebrovascular events occurred in 17.4%, gastrointestinal complications in 18.8%, and renal replacement therapy in 65.0%. Risk factors for hospital mortality were age older than 70 years (odds ratio, 1.6), diabetes (odds ratio, 2.5), preoperative renal insufficiency (odds ratio, 2.1), obesity (odds ratio, 1.8), logistic EuroSCORE greater than 20% (odds ratio, 1.8), operative lactate greater than 4 mmol/L (odds ratio, 2.2). Isolated coronary artery bypass grafting (odds ratio, 0.44) was protective. Cumulative survivals were 17.6% after 6 months, 16.5% after 1 year, and 13.7% after 5 years. CONCLUSIONS Extracorporeal membrane oxygenation support is an acceptable option for patients with postcardiotomy cardiogenic shock who otherwise would die and is justified by good long-term outcome of hospital survivors. Because of high morbidity and mortality, extracorporeal membrane oxygenation must be decided by individual risk profile.

Five-Year results of 219 consecutive patients treated with extracorporeal membrane oxygenation for refractory postoperative cardiogenic shock

BACKGROUND Postcardiotomy cardiogenic shock occurs in approximately 1% of patients. We prospectively evaluated the early and long-term outcome as well as predictors of survival when using temporary extracorporeal membrane oxygenation (ECMO) support. METHODS During 5 years 219 of 18150 patients (1.2%) undergoing cardiac surgery (coronary artery bypass grafting, n = 119; aortic valve replacement, n = 24; coronary artery bypass grafting and aortic valve replacement, n = 21; coronary artery bypass grafting and mitral valve replacement, n = 11; other procedures, n = 44) required temporary postoperative ECMO support. The ECMO implantation was performed through the femoral vessels or through the right atrium and ascending aorta. Additional intraaortic balloon counterpulsation was employed in 144 patients to improve coronary blood flow. RESULTS Mean duration of ECMO support was 2.8 +/- 2.2 days. One hundred thirty-four patients (60%) were successfully weaned from ECMO. Of these, 52 patients (24%) were discharged from the hospital after 29.9 +/- 24 days. The main cause of death was myocardial failure. Five-year follow-up is 96% complete; 37 patients (74%) were alive with reasonable exercise capacity. CONCLUSIONS Extracorporeal membrane oxygenation is an acceptable technique for short-term treatment of refractory postoperative low cardiac output. It can save the lives of a group of very high risk patients.

Predictors of delirium after cardiac surgery delirium: Effect of beating-heart (off-pump) surgery

BACKGROUND Despite improved outcomes after cardiac operations, postoperative delirium remains a common complication that is associated with increased morbidity and prolonged hospital stay. METHODS Univariate and multivariate predictors of postoperative delirium were determined from prospectively gathered data on 16,184 patients undergoing cardiac operations with cardiopulmonary bypass (conventional, n = 14,342) and without cardiopulmonary bypass (beating-heart surgery, n = 1847) between April 1996 and August 2001. Delirium was defined as a transient mental syndrome of acute onset characterized by global impairment of cognitive functions, a reduced level of consciousness, attentional abnormalities, increased or decreased psychomotor activity, and a disordered sleep-wake cycle. RESULTS The overall prevalence of postoperative delirium was 8.4%. Of 49 selected patient-related risk factors and treatment variables, 35 were highly associated with postoperative delirium by univariate analysis. Stepwise logistic regression revealed the following variables as independent predictors of delirium: history of cerebrovascular disease, peripheral vascular disease, atrial fibrillation, diabetes mellitus, left ventricular ejection fraction of 30% or less, preoperative cardiogenic shock, urgent operation, intraoperative hemofiltration, operation time of 3 hours or more, and a high perioperative transfusion requirement. Two variables were identified as having a significant protective effect against postoperative delirium: beating-heart surgery and younger patient age. CONCLUSIONS Postoperative delirium is a common complication in cardiac operations. The increased use of beating-heart surgery without cardiopulmonary bypass may lead to a lower prevalence of this complication and thus improve patient outcomes.

Minimal invasive mitral valve repair for mitral regurgitation: results of 1339 consecutive patients

OBJECTIVE Some have expressed concern that minimal invasive mitral valve (MV) repair may not meet the standard of open surgical techniques. We therefore reviewed our results for minimal invasive MV repair for mitral regurgitation (MR). MATERIAL AND METHODS Between March 1999 and February 2007, a total of 1536 consecutive patients underwent minimal invasive MV surgery for MR at our institution using a right lateral mini-thoracotomy and femoral cannulation for cardiopulmonary bypass. Of these, a total of 1339 (87.2%) patients underwent MV repair and these form the focus of this study. The mean grade of preoperative MR was 3.3+/-0.6, age was 60.3+/-12.7 years, ejection fraction was 59.2+/-15.1% and 819 patients (61.2%) were male. RESULTS The procedure was successfully performed in all but four patients (0.3%) who required intraoperative conversion to full sternotomy. MV repair techniques consisted of ring annuloplasty with or without chordae-replacement or Carpentier-type leaflet resection. Concomitant procedures consisted of atrial fibrillation ablation in 351 patients (26.2%), tricuspid valve surgery in 80 patients (6.0%), and patent foramen ovale/atrial septal defect closure in 88 patients (6.6%). Mean duration of CPB was 121+/-38min and mean aortic cross-clamp time was 70+/-32min. Thirty-day mortality was 2.4%. Follow-up was performed in 99% of patients at an average of 28.1+/-23.9 months postoperatively. The Kaplan-Meier estimate for survival at 5 years was 82.6% (95% CI: 78.9-85.7%) and for freedom from MV reoperation was 96.3% (95% CI: 94.6-97.4%). CONCLUSIONS Minimal invasive MV repair, along with certain concomitant procedures, can be performed in the vast majority of patients with MR. Our large series demonstrates that these procedures can be performed with low perioperative complication rates and very good durability.

How does the use of polytetrafluoroethylene neochordae for posterior mitral valve prolapse (loop technique) compare with leaflet resection? A prospective randomized trial

OBJECTIVE Mitral valve surgery for posterior mitral leaflet prolapse consists mostly of leaflet resection, but implantation of premeasured polytetrafluoroethylene neochordae (ie, loops) is another option. The aim of this prospectively randomized trial was to determine how preservation of leaflet structure in combination with premeasured neochordae compares with the widely adopted technique of leaflet resection. METHODS A total of 129 patients with severe mitral regurgitation, with a mean mitral regurgitation grade of 3.6 +/- 0.6, underwent minimal invasive mitral valve surgery through a right lateral mini-thoracotomy. The mean age was 59.5 +/- 12 years, 90 patients were male, the mean preoperative ejection fraction was 65% +/- 8%, and the mean New York Heart Association functional class was 2.1 +/- 0.7. Posterior mitral leaflet prolapse was diagnosed in all patients. Randomization was performed preoperatively, and crossover was allowed if the surgeon deemed it medically necessary. Crossover from resection to loops occurred in 9 patients, and crossover from loops to resection occurred in 3 patients. RESULTS Mitral valve repair was accomplished in all patients (n = 129, 100%), and all patients received an annuloplasty ring. The mean number of loops implanted on the posterior mitral leaflet was 3.2 +/- 0.9, with a mean length of 13.3 +/- 2.2 mm. The mean duration of cardiopulmonary bypass was 135 +/- 37 minutes and the mean aortic crossclamp time was 82 +/- 26 minutes in all patients, with no significant difference between groups. Intraoperative transesophageal echocardiography showed a significantly longer line of mitral valve leaflet coaptation after implantation of loops (7.6 +/- 3.6 mm) than after resection (5.9 +/- 2.6 mm; P = .03). Thirty-day mortality was 1.6% for the entire group (2/129), with both deaths occurring in the loop group. Cause of death was massive pulmonary embolism in 1 patient and acute right heart failure in 1 patient. Early and mid-term echocardiographic follow-up revealed excellent valve function in the majority of patients, with no significant difference in mitral orifice area (3.6 +/- 1.0 cm(2) vs 3.7 +/- 1.1 cm(2), P = .4). CONCLUSION Both repair techniques for posterior mitral leaflet prolapse are associated with excellent results and appear comparable in the early postoperative course. The loop technique, however, results in a significantly longer line of leaflet coaptation and may therefore be more durable. Longer follow-up is required.

Emergency coronary artery bypass graft surgery for acute coronary syndrome : Beating heart versus conventional cardioplegic cardiac arrest strategies

Background— Aim of this study was to compare the outcome of beating heart versus conventional coronary artery bypass graft (CABG) strategies in acute coronary syndromes for emergency indications. Methods and Results— 638 consecutive patients with acute coronary syndrome (ACS) receiving emergency CABG surgery via midline sternotomy from January 2000 to September 2005 were evaluated. Propensity score analysis was used to predict the probability of undergoing beating heart (BH) (n=240) versus cardioplegic cardiac arrest (CA) (n=398) strategies. Patients presented with stable hemodynamics (n=531) or in cardiogenic shock (CS) (n=107). Hospital and follow-up outcome was compared by propensity score adjusted multiregression analysis. BH included 116 on-pump and 124 off-pump (OPCAB) procedures. There was a propensity to operate CS patients on the beating heart (multivariate odds ratio [OR], 3.8; P=0.001). Under stable hemodynamics significant predictors for BH selection were logEuroSCORE >20% (OR, 2.05), creatinine >1.8 mg/dL (OR, 4.12), complicated percutaneous coronary intervention (OR, 1.88), ejection fraction <30% (OR, 2.64), whereas left main disease (OR, 0.68), circumflex artery (OR, 0.32), and 3-vessel disease (OR, 0.67) indicated preference for cardioplegic arrest. Time from skin incision to culprit lesion revascularization was significantly reduced in BH patients. BH surgery led to a significant benefit in terms of less drainage loss, less transfusion requirement, less inotropic support, shorter ventilation time, lower stroke rate, and shorter intensive care unit stay. In CS, BH was associated with lower incidence of stroke, inotropic support, acute renal failure, new atrial fibrillation and sternal wound healing complications. In CS patients, hospital mortality rate was reduced when using beating heart strategies (P=0.048). Overall survival, major adverse cerebral and cardiovascular event rate, and repeated revascularization was comparable during a 5-year follow-up. Conclusions— Beating heart strategies are associated with an improved hospital outcome and comparable long-term results for high-risk patients presenting acute coronary syndrome with or without CS.

Chordae Replacement Versus Resection for Repair of Isolated Posterior Mitral Leaflet Prolapse: À Ègalité

BACKGROUND Mitral valve (MV) repair for posterior mitral leaflet (PML) prolapse has proven excellent results. The loop technique, which involves insertion of polytetrafluoroethylene neochordae while preserving the native PML tissue, was developed to facilitate MV repair through a minimally invasive approach. The aim of this study was to assess the medium-term results of the loop technique in comparison with the widely adopted leaflet resection technique for repair of isolated PML prolapse. METHODS Between March 1999 and January 2008, a total of 1,708 patients underwent minimally invasive MV repair. Six hundred and seventy patients (39.2%) had isolated PML prolapse and were treated with either the loop technique (n = 317) or the leaflet resection (n = 353) technique, according to surgeon preference. Mean follow-up time was 2.8 +/- 2.2 years, and follow-up was 99% complete. RESULTS Early postoperative echocardiography showed a significantly larger mitral orifice area (3.3 +/- 0.3 cm(2) versus 3.0 +/- 0.8 cm(2), p < 0.001) and lower mean pressure gradient (2.7 +/- 1.7 mm Hg versus 3.1 +/- 1.7 mm Hg, p = 0.03) after implantation of loops. Other perioperative outcomes were similar for the two groups of patients. Freedom from reoperation at 5 years was significantly higher after the loop technique (98.7%, 95% confidence interval [CI]: 96.7% to 99.5%) when compared with leaflet resection (93.9%, 95% CI: 90.7% to 96.1%, log-rank p = 0.005). Cox regression analysis revealed that implantation of a flexible, incomplete band was an independent predictor of reoperation (hazard ratio 6.2, 95% CI: 1.3 to 110.7), whereas use of leaflet resection had a nonsignificant trend toward an increased reoperation rate (hazard ratio 2.6, 95% CI: 0.9 to 9.1). Reoperation for excessive systolic anterior motion did not occur in any loop patient. CONCLUSIONS Both the loop technique and conventional leaflet resection yield excellent results for repair of isolated PML prolapse. The technical ease of performing the loop technique through a minimally invasive approach, however, makes this method a particularly valuable alternative for MV repair surgery.

Minimal access aortic valve replacement: effects on morbidity and resource utilization

BACKGROUND The aim of this study was to compare outcomes in patients undergoing minimal access versus conventional aortic valve replacement (AVR). METHODS We reviewed prospectively gathered data on all patients who were undergoing first-time AVR, with or without replacement of the ascending aorta, over a 1-year period at our institution. RESULTS A total of 176 patients underwent minimal access and 258 underwent conventional AVR. The conventional group was older, had more incidence of diabetes, and more aortic stenosis (all p < 0.05). Eight minimal access AVR patients (2%) required conversion to a complete sternotomy. Minimal access AVR patients had longer aortic crossclamp times than conventional AVR patients (60 +/- 22 vs 55 +/- 23 minutes, p = 0.03) but similar CPB times (93 +/- 38 vs 88 +/- 42 minutes, p = 0.20). Postoperative creatine kinase-MB levels were similar for the two groups. Total postoperative blood loss was significantly lower in the minimal access group, and these patients received less red blood cell and fresh frozen plasma transfusions. Minimal access AVR patients were less likely to have postoperative respiratory failure (3% vs 10%); they had shorter intensive care unit stays (3.7 +/- 5.4 vs 4.5 +/- 5.6 days) and shorter hospital stays (10 +/- 6 vs 12 +/- 7 days, all p < 0.05). Mortality was lower in patients undergoing minimal access surgery (3% vs 9%, p = 0.008) by univariate analysis. Multivariate predictors of mortality were age, hypertension, and CPB time. CONCLUSIONS Although patient selection may have influenced some of the observed differences between our patient groups, minimal access surgery appears to be associated with decreased morbidity and resource use when compared to conventional AVR.

Comparison of outcomes of minimally invasive mitral valve surgery for posterior, anterior and bileaflet prolapse

OBJECTIVE We sought to compare the outcomes of minimally invasive mitral valve (MV) surgery for anterior (anterior mitral leaflet, AML), posterior (posterior mitral leaflet, PML) or bileaflet (BL) MV prolapse. METHODS Between August 1999 and December 2007, 1230 patients who presented with isolated AML (n=156, 12.7%), isolated PML (n=672, 54.6%) or BL (n=402, 32.7%) MV prolapse underwent minimally invasive MV surgery. The preoperative mitral regurgitation (MR) grade was 3.3+/-0.8, left ventricular ejection fraction (LVEF) was 62+/-12% and mean age was 58.9+/-13.0 years; 836 patients (68.0%) were male. Mean follow-up time was 2.7+/-2.1 years, and the follow-up was 100% complete. RESULTS Overall, the MV repair rate was 94.0% (1156 patients). Seventy-four patients (6.0%) received MV replacement. MV repair for PML prolapse was accomplished in 651 patients (96.9%), for AML in 142 patients (91%) and for BL in 363 patients (90.3%). Repair techniques consisted predominantly of leaflet resection and/or implantation of neochordae, combined with ring annuloplasty. Concomitant procedures were tricuspid valve surgery (n=56), atrial fibrillation ablation (n=286) and closure of an atrial septal defect or patent foramen ovale (PFO) (n=89). The overall duration of cardiopulmonary bypass was 127+/-40 min and aortic cross-clamp time was 78+/-33 min. The mean postoperative hospital stay was 11.6+/-9.7 days for the overall group. Early echocardiographic follow-up revealed excellent valve function in the vast majority of patients, regardless of the repair technique, with a mean MR grade of 0.3+/-0.5. For the overall group, 5-year survival rate was 87.3% (95% CI: 83.9-90.1) and 5-year freedom from cardiac reoperation rate was 95.6% (95% CI: 94.1-96.7). The log-rank test revealed no significant difference between the three groups regarding long-term survival or freedom from reoperation. CONCLUSIONS Minimally invasive MV repair can be achieved with excellent results. Long-term outcomes and reoperation rates for AML prolapse are not significantly different from PML or BL prolapse.