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Volkmar Falk

Publications and source records attributed to Volkmar Falk.

At least 37 records · Page 2Linked to original sources

Redo minimally invasive direct coronary artery bypass grafting.

BACKGROUND: Conventional redo coronary artery bypass grafting is associated with an increased risk of mortality and morbidity as a result of manipulation of patent grafts, mediastinitis, and the presence of pericardial adhesions. Minimally invasive direct coronary artery bypass grafting may be an alternative approach in selected patients. METHODS: From January 1997 to October 2003, 46 patients (mean age, 66 +/- 7.4 years) underwent minimally invasive direct coronary artery bypass grafting using the left internal thoracic artery to the left anterior descending artery on the beating heart as a reoperation. Patients after previous cardiac operation by means of median sternotomy without use of the left internal thoracic artery presenting with a significant left anterior descending artery stenosis ("culprit lesion") were included. Predicted mortality was 13.6% (range, 2.4% to 72.8%) as calculated by the logistic Euroscore; ejection fraction was 0.531 (range, 0.14 to 0.81). Surgical results were analyzed for mortality, morbidity, duration of the procedure, hospital stay, and event-free survival. RESULTS: Mean operating time was 103 +/- 34 minutes. There were two in-hospital deaths (4.6%), one for malignant ventricular arrhythmia (Euroscore, 60.9%) and the second as a result of severe gastrointestinal bleeding (Euroscore, 29.2%). One patient (2.3%) was successfully reoperated on because of perianastomotic hematoma using the same approach after 6 days. Patients were discharged after 9.4 +/- 2.6 days. There were no other serious adverse events, no stroke, and no myocardial infarction. During follow-up (37 +/- 21 months, complete in 92.1%), 1 patient experienced angina and 6 patients died. The actuarial 4-year survival is 74.8% (95% confidence interval, 51% to 92%), and the actuarial 4-year event-free survival including freedom from angina, major adverse cardiac events, and reintervention is 81% (95% confidence interval, 54% to 97%). CONCLUSIONS: Minimally invasive direct coronary artery bypass grafting can be considered as an alternative approach for redo coronary artery bypass grafting in selected patients.

Aged↗

A novel adhesion barrier facilitates reoperations in complex congenital cardiac surgery.

OBJECTIVE: Reoperations are associated with an increased surgical risk due to adhesions. We prospectively evaluated a bioresorbable membrane after surgery for congenital heart defects over a 3.5-year period. METHODS: The surgical membrane (CV Seprafilm, Genzyme, Cambridge, Mass) was applied in 350 of 1024 patients; 30 of them underwent reoperation and were evaluated in comparison to 10 random reoperated patients. Adhesions were evaluated using a subjective scoring system [1 (lowest tenacity) to 5 (highest tenacity)] and extent in percent at different regions of the heart. RESULTS: Patients were operated for atrioventricular septal defect (69), tetralogy of Fallot (65), functional single ventricle (75), valve surgery (48), ventricular septal defect (20), subaortic stenosis (17), hypoplastic left heart syndrome (17), and other diagnoses (39). Application of the surgical membrane was safe in all patients, without any infections. At reoperation patients received Glenn (14), total cavopulmonary connection (6), and others (10). Overall mortality was 2/350 (0.57%). There was a remarkable reduction in tenacity score (3.3 vs 4.3) and in the extent of adhesions (77.7% vs 86%). Duration of reoperation was significantly reduced. CONCLUSIONS: A bioresorbable surgical membrane leads to a significant reduction in the tenacity and amount of adhesions. It is recommended for general use whenever repeat operation is anticipated in congenital as well as in adult cardiac surgery.

Aortic Valve Stenosis↗

Significant value of autopsy for quality management in cardiac surgery.

OBJECTIVE: With recent advances in diagnostic imaging, the value of autopsy has been called into question. The aim of our study was to assess the current impact of autopsy for early postoperative quality management in cardiac surgery. METHODS: Between 2000 and 2003, a total of 14,313 patients underwent cardiac surgery at our center. Of these, 898 patients (6.3%) died, and autopsy was performed in 468 cases (52.1%). Data from clinical and postmortem examination were prospectively analyzed regarding causes of death, postoperative complications, concomitant diseases, and surgery-associated pathologic findings. RESULTS: Mean age was 68.7 years. Mean survival was 13.9 postoperative days. On autopsy, causes of death were cardiac in 49.8% of cases (n = 233), respiratory in 8.3% (n = 39), cerebral in 6.4% (n = 30), abdominal in 4.7% (n = 22), multiorgan failure or sepsis in 14.9% (n = 70), pulmonary embolism in 6.6% (n = 31), procedure associated in 8.3% (n = 39), and others in 0.9% (n = 4). Discrepancies between clinical and postmortem determinations of cause of death were found in 108 cases (23.1%). These were acute myocardial infarction (n = 38), low cardiac output (n = 9), respiratory (n = 8), cerebral (n = 5), abdominal (n = 7), multiorgan failure or sepsis (n = 12), pulmonary embolism (n = 18), and procedure associated (11). Clinically unrecognized postoperative complications were found in 364 cases (77.8%). Unknown concomitant diseases were found in 464 cases (99.1%), with potential therapeutic relevance in 90 cases (19.2%). In 85 cases (18.2%), autopsy examination revealed 96 premortem unrecognized surgery-associated pathologic findings. CONCLUSION: A high overall discrepancy rate between premortem and autopsy diagnoses was recognized. Autopsy revealed clinically relevant information in a significant number of cases. Therefore autopsy remains essential for quality assessment in perioperative treatment.

Aged↗

Facilitated MIDCAB using a magnetic coupling device.

A 59-year-old male with chronic occlusion of the left anterior descending coronary artery underwent a minimally invasive direct coronary artery bypass procedure using the second generation of a magnetic anastomotic coupling device. Postoperative angiogram demonstrated excellent patency and flow.

Anastomosis, Surgical↗

Motion estimation in beating heart surgery.

Minimally invasive beating-heart surgery offers substantial benefits for the patient, compared to conventional open surgery. Nevertheless, the motion of the heart poses increased requirements to the surgeon. To support the surgeon, algorithms for an advanced robotic surgery system are proposed, which offer motion compensation of the beating heart. This implies the measurement of heart motion, which can be achieved by tracking natural landmarks. In most cases, the investigated affine tracking scheme can be reduced to an efficient block matching algorithm allowing for realtime tracking of multiple landmarks. Fourier analysis of the motion parameters shows two dominant peaks, which correspond to the heart and respiration rates of the patient. The robustness in case of disturbance or occlusion can be improved by specially developed prediction schemes. Local prediction is well suited for the detection of single tracking outliers. A global prediction scheme takes several landmarks into account simultaneously and is able to bridge longer disturbances. As the heart motion is strongly correlated with the patient's electrocardiogram and respiration pressure signal, this information is included in a novel robust multisensor prediction scheme. Prediction results are compared to those of an artificial neural network and of a linear prediction approach, which shows the superior performance of the proposed algorithms.

Algorithms↗

Anastomotic devices for coronary artery bypass grafting.

With the advent of off-pump and minimally invasive coronary artery bypass grafting, efforts to facilitate construction of the graft to coronary anastomosis have increased. As a result, a number of anastomotic devices have been developed. While the ideal anastomotic device should be easy to use, produce a geometrically optimal anastomosis with minimal endothelial damage and minimal blood-exposed nonintimal surface, a number of design constraints apply. This review collects the available preclinical and clinical data for some of the devices, with special regard as to surgical outcome, patency rate and the need for additional perioperative anticoagulation treatment.

Anastomosis, Surgical↗

Augmented reality for intraoperative guidance in endoscopic coronary artery bypass grafting.

Endoscopic bypass grafting can be complicated by limited intraoperative orientation. A method to overlay the preoperative model of the coronary tree on the live endoscopic images of the heart was therefore developed. The method is three-fold: (1) the three-dimensional (3D) model of the coronary tree is reconstructed from traditional angiograms; (2) preoperative images are registered with the intraoperative position of the patient in the operating room (OR); and (3) an iterative and interactive identification of clinically relevant landmarks within the operative field on the heart surface before their registration with the preoperative model of the coronaries. This algorithm allows one to compensate deformations (breathing, intraoperative heart shift) and leads to a precise overlay of the coronary network on the heart surface. For ergonomic reasons, the 3D model can be displayed directly within the visual field of any telesurgical master console. It thus provides an effective navigational aid to the surgeon similar to a global positioning system (GPS) in vehicles. Animal trials have been performed using the Da Vinci (Intuitive Surgical, Sunnyvale, CA, USA) teleoperated system to validate the method. Qualitative and quantitative analysis demonstrate the potential value during total endoscopic coronary artery bypass grafting.

Coronary Angiography↗

Stentless mitral valve replacement by conventional and minimally invasive techniques.

Stentless mitral valve (SMV) replacement is an intriguing concept to preserve the functionality of the physiological mitral valve (MV). Beginning in August 1997 to date, 51 patients, 35 females and 16 males (age: 68.3+/-8.4 years), with severe MV disease (stenosis 25, incompetence 17, mixed lesion 9) received a chordally supported SMV. SMV implantation was performed using a conventional sternotomy in 32, or a minimally invasive lateral minithoracotomy approach in 19 of the patients. Mean valve size was 29+/-1.5 mm; cross-clamp duration was 81+/-33 min. The perioperative mortality rate was comparable to conventional MV repair or replacement. Regular echocardiographic control disclosed good SMV function (Vmax 1.7+/-0.2 m/s, Pmean 3.9+/-1.2 mmHg) and well-preserved ejection fraction postoperatively, as well as at their most recent follow-up visit. SMV implantation by way of a sternotomy or lateral minithoracotomy leads to preservation of the annulo-ventricular continuity and similar to physiological hemodynamics. However, long-term durability remains to be proven.

Aged↗

Prospectively randomized evaluation of stented xenograft hemodynamic function in the aortic position.

BACKGROUND: Standard stented aortic xenograft valves have not yet been compared regarding their hemodynamic function using a stratified intraoperative randomization protocol. METHODS AND RESULTS: 100 patients were prospectively included after intraoperative metric sizing of the decalcified aortic annulus. They received Mosaic (M) or Perimount (P) aortic valve replacement. Patient age was 73+/-5 years, 51 were female, and New York Heart Association (NYHA) functional class was 2.8+/-0.5. The 21-mm annulus group consisted of 5 (M)/7 (P) patients, the 23-mm annulus group of 20 (M)/20 (P), the 25-mm annulus group of 18 (M)/19 (P), and the 27-mm annulus group of 4 (M)/7 (P) patients, respectively. Hemodynamic function was evaluated using transthoracic echocardiography before discharge and at follow-up (438+/-352 days). Surgery was uncomplicated in all patients. Labeled valve sizes were 0.93 (M) and 1.05 (P) mm smaller than the annulus diameters (p=NS). In-hospital mortality was 5%, all nonvalve-related. Transvalvular blood flow velocities and transvalvular pressure gradients were significantly lower in the 25 P versus the 25 M group at baseline and in the 23 P and 25 P groups at follow-up. There was a significant regression of left ventricular mass index in all patients at follow-up. However, left ventricular mass regression was more pronounced after P aortic valve replacement. CONCLUSIONS: Labeled sizes of prosthetic heart valves implanted are smaller than the true aortic annulus. Both standard aortic xenografts compared in this prospectively randomized trial provide a sufficient hemodynamic and functional outcome.

Aged↗

Three-dimensional echocardiography for planning of mitral valve surgery: current applicability?

BACKGROUND: Two-dimensional transesophageal echocardiographic (2D TEE) assessment of the mitral valve requires mental integration of a limited number of 2D imaging planes. Structural display in three dimensions from any perspective may be of advantage to the surgeon for better judgment and planning. METHODS: Feasibility, accuracy, and limitations of preoperative three-dimensional transesophageal echocardiography (3D TEE) was assessed in 51 patients with mitral valve disease. The width of the anterior mitral valve was measured with either method and compared with the operative finding. Three-dimensional dynamic sequences of the reconstructed mitral valve were shown preoperatively to the surgeon and later compared with the intraoperative finding. RESULTS: The quality of the 3D reconstruction was graded as good in 25 patients (49.0%), fair in 16 patients (31.4%), and poor in 10 patients (19.6%) where atrial fibrillation did not allow ECG gating. Thirty-nine patients had successful mitral valve repair and twelve patients required valve replacement. Based on intraoperative findings, sensitivity for the diagnosis of mitral valve prolapse using 2D TEE and 3D TEE was 97.7% and 92.9% (p = ns) respectively and specificity was 100% by both methods. Sensitivity for the diagnosis of rupture of chordae tendineae using 2D TEE and 3D TEE was 92.3% and 30.8% respectively (p < 0.05) and specificity was 100% by both methods. CONCLUSIONS: Dynamic 3D echocardiography is feasible and can provide good insight into valvular motion and allows adequate preoperative planning when reconstruction is being considered. However dynamic 3D reconstruction is currently limited by the quality of the original 2D echo cross sectional images which can be adversely affected by minimal patient movements, breathing, or cardiac arrhythmia, thus limiting accuracy of the 3D TEE significantly compared with 2D TEE.

Aged↗

On-pump versus off-pump coronary artery bypass grafting: impact on postoperative renal failure requiring renal replacement therapy.

BACKGROUND: Despite refinements in perioperative patient management postoperative renal failure requiring hemofiltration or dialysis is still a common complication after coronary artery bypass grafting associated with impaired patient outcome. METHODS: Prospective data on 9,631 patients receiving myocardial revascularization with (coronary artery bypass grafting [n = 8,870]) or without cardiopulmonary bypass (off-pump coronary artery bypass grafting [n = 761]) between April 1996 and August 2001 were evaluated by univariate and multivariate logistic regression analysis. RESULTS: Overall prevalence of postoperative continuous renal replacement therapy was 4.1% (coronary artery bypass grafting, 4.3%; off-pump coronary artery bypass grafting, 1.8%; p = 0.001). Thirty of 40 selected preoperative and intraoperative patient and treatment related variables had a high association with the requirement for postoperative renal replacement therapy; fifteen of these variables were independent predictors in the whole study population. Off-pump coronary artery bypass surgery was identified as having a significantly lower predictive value for postoperative continuous renal placement therapy. In the subgroup of patients undergoing off-pump coronary artery bypass grafting surgery, a second multivariate logistic regression model revealed preoperative cardiogenic shock, urgent operation, intraoperative low cardiac output, and high transfusion requirement as independent predictors for postoperative renal replacement therapy. CONCLUSIONS: Patients with preoperative nondialysis dependent renal insufficiency are at a high risk for further decline in renal function requiring postoperative continuous renal replacement therapy. Off-pump coronary artery bypass surgery is associated with a lower prevalence of postoperative renal replacement therapy after coronary artery bypass grafting.

Aged↗

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.

Age Distribution↗

Restitution of sinus rhythm plus stentless mitral valve replacement at three years.

BACKGROUND AND AIM OF THE STUDY: The study aim was to examine results after stentless mitral valve (SMV) replacement (Quattro) and restitution of physiological cardiac rhythm by intraoperative left atrial ablation therapy. METHODS: Twenty patients (13 females; mean age 69.7 +/- 5.9 years) with severe degenerative mitral valve disease (six with valve stenosis, six with valve incompetence, eight with combined lesion) were prospectively evaluated since 1998. The mean NYHA functional class was 3.2 +/- 0.4, and cardiac index 1.8 +/- 0.5 l/min/m2. Ablation therapy was performed by inducing left atrial linear lesion lines to avoid reentrant circuits. RESULTS: Surgery was performed using conventional sternotomy (n = 10) or lateral minithoractomy (n = 10). Sinus rhythm was successfully restituted in 17 patients either postoperatively or in the long term (success rate 85%). However, three patients required DDD-pacemaker implantation, and another three had to be discharged with persistent atrial fibrillation. Intermittent medical therapy (sotalol or amiodarone) was required in nine patients postoperatively, in four patients at six months, and in two patients at one-year follow up. One patient was reoperated on for paravalvular leak after one year, but subsequently died due to sepsis. In the other patients, echocardiographic control proved good SMV function with atrial contraction. CONCLUSION: Restitution of physiological cardiac function is possible by combined stentless MV implantation and left atrial ablation therapy. A persistent benefit, without need for additional re-intervention, was shown at mid-term follow up.

Aged↗

Early results with stentless mitral valve replacement.

BACKGROUND AND AIM OF THE STUDY: Implantation of a chordally supported stentless mitral valve (SMV) may be the strategy of choice for patients with severe degenerative mitral valve disease. Herein, the early clinical results of this surgical technique were analyzed. METHODS: Since August 1997, 52 patients (36 females, 16 males; mean age 68.0 +/- 8.5 years) each received a SMV (Quattro; St. Jude Medical Inc.) at the authors' institution. The underlying disease was predominant mitral stenosis (n = 26), incompetence (n = 17) and combined lesion (n = 9). The mean NYHA class was 3.1 +/- 0.6, left ventricular ejection fraction 64 +/-13%, and cardiac index 2.1 +/- 0.8 1/min/m2. RESULTS: SMV implantation was performed using either a conventional sternotomy (n = 33) or a lateral minithoracotomy (n = 19). The mean implanted valve size was 29.2 +/- 1.7 mm, and mean cross-clamp time 81 +/- 33 min. Reoperation was required in six patients: two for paravalvular leakage, two for functional stenosis (both 26 mm valves), in one patient for pannus formation with underlying collagenosis, and in one for papillary flap rupture at five years. One patient died perioperatively, one died after reoperation at one year, and five patients died at longer follow up, from non-cardiac causes. Hemodynamic function was shown to be normal on echocardiography. CONCLUSION: Intermediate-term results after SMV implantation were promising. Preservation of annuloventricular continuity led to good left ventricular function, but long-term durability remains to be proven.

Aged↗

Predictors of prolonged ICU stay after on-pump versus off-pump coronary artery bypass grafting.

OBJECTIVE: To define predictors for prolonged ICU stay in order to improve patient outcome and reduce costs. PATIENTS AND METHODS: Prospective data on 10,759 patients undergoing coronary artery bypass grafting with and without use of cardiopulmonary bypass (coronary artery bypass grafting, CABG; n =8,917; off-pump coronary artery bypass grafting, OPCAB; n =765; minimally invasive direct coronary artery bypass grafting, MIDCAB; n =1,077) between April 1996 and August 2001 were subjected to univariate and, consecutively, to multivariate logistic regression analysis. Prolonged ICU stay was defined as intensive care treatment for three postoperative days and longer. MEASUREMENTS AND RESULTS: Mean duration of ICU stay was 3.8+/-6.9 days; overall prevalence of prolonged ICU stay was 37.1%. The hospital mortality was 3.5% (ICU > or =3 days: 5.9%; ICU <3 days: 2.0%). Out of 39 selected pre- and intraoperative patient- and treatment-related variables, by univariate analysis, 32 variables having a high association with prolonged ICU stay were identified. Using a stepwise logistic regression model, 20 variables were shown to be independent predictors for prolonged ICU stay. Both OPCAB and MIDCAB surgery were identified as having a significantly lower association with prolonged ICU stay. CONCLUSION: As prolonged ICU stay is associated with poor patient outcome and increased costs it is of utmost importance to identify patients at a high risk for prolonged ICU stay. More frequent off-pump CABG may optimize patient outcome.

Aged↗

Midterm results after stentless mitral valve replacement.

BACKGROUND: To analyze the midterm clinical results after stentless mitral valve (SMV) replacement. METHODS AND RESULTS: Fifty one patients (68.3+/-8.4 years, 35 female) with severe mitral valve disease (stenosis 25, incompetence 17, mixed lesion 9) received a chordally supported SMV (Quattro, St. Jude Medical Inc.) since August 1997. Preoperative New York Heart Association class was 3.1+/-0.6; left ventricular ejection fraction 64+/-13%, and cardiac index 2.1+/-0.8 l/min/m2. Additional intraoperative ablation therapy was performed on 19 patients with chronic atrial fibrillation. Mean follow-up is 35.4+/-19.2 months (range 5 to 63). SMV implantation was performed using a conventional (32) or a minimally invasive (19) approach, valve size was 29+/-1.5 mm, cross-clamp duration was 81+/-33 minutes. Atrial rhythm was reestablished in 16 of 19 patients. Five patients required reoperation early in this series, two for paravalvular leakage, two for functional stenosis, and one with underlying rheumatoid disease. Mortality was one perioperative (1.96%, non-valve-related), one after reoperation as a result of multiple organ failure (MOF), and five during late follow-up (30+/-7 months postoperatively) for noncardiac causes. Regular echocardiographic control revealed good SMV function (Vmax 1.7+/-0.2m/s, P(mean) 3.9+/-1.2 mm Hg) and well-preserved ejection fraction postoperatively and at most recent follow-up. CONCLUSIONS: Midterm results after SMV implantation are promising. Preservation of the annuloventricular continuity leads to stable left ventricular function and combined with ablation therapy to physiological hemodynamics. Long-term durability remains to be proven.

Aged↗

Short- and long-term hemodynamic effects of intra-aortic balloon support in ventricular septal defect complicating acute myocardial infarction.

In patients with an infarct-related ventricular septal defect, an intra-aortic balloon pump provides immediate and long-term hemodynamic improvement, resulting in an enhanced effective cardiac output and a reduced left-to-right-shunt and shunt flow ration. In patients who can be stabilized or remain stable, there is no habituation to the effects of the intra-aortic balloon pump; thus, later surgical closure of the ventricular septal defect might be possible in some patients.

Aged↗

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.

Adult↗