[Show abstract][Hide abstract] ABSTRACT: Less invasive approaches to mitral valve surgery are increasingly used for improved cosmesis; however, few studies have investigated their effect on outcome. We sought to compare these minimally invasive approaches fairly with conventional full sternotomy by using propensity-matching methods.
From January 1995 to January 2004, 2124 patients underwent isolated mitral valve surgery through a minimally invasive approach, and 1047 underwent isolated mitral valve surgery through a conventional sternotomy. Because there were important differences in patient characteristics, a propensity score based on 42 factors was used to obtain 590 well-matched patient pairs (56% of cases).
In-hospital mortality was similar for propensity-matched patients: 0.17% (1/590) for those undergoing minimally invasive surgery and 0.85% (5/590) for those undergoing conventional surgery (P = .2). Occurrences of stroke (P = .8), renal failure (P > .9), myocardial infarction (P = .7), and infection (P = .8) were also similar. However, 24-hour mediastinal drainage was less after minimally invasive surgery (median, 250 vs 350 mL; P < .0001), and fewer patients received transfusions (30% vs 37%, P = .01). More patients undergoing minimally invasive surgery were extubated in the operating room (18% vs 5.7%, P < .0001), and postoperative forced expiratory volume in 1 second was higher. Early after operation, pain scores were lower (P < .0001) after minimally invasive surgery.
Within that portion of the spectrum of mitral valve surgery in which propensity matching was possible, minimally invasive mitral valve surgery had cosmetic, blood product use, respiratory, and pain advantages over conventional surgery, and no apparent detriments. Mortality and morbidity for robotic and percutaneous procedures should be compared with these minimally invasive outcomes.
Full-text · Article · Nov 2009 · The Journal of thoracic and cardiovascular surgery
[Show abstract][Hide abstract] ABSTRACT: Recommendations for aortic valve replacement in severe aortic stenosis are based primarily on the presence of symptoms. However, the onset of symptoms is often insidious, potentially leading to delayed intervention and suboptimal results. Identifying factors that reduce the survival of patients undergoing aortic valve replacement could lead to revised treatment guidelines and improved outcomes.
We conducted a single-center observational clinical study of 3049 patients with aortic stenosis who underwent native aortic valve replacement with a single type of bioprosthesis. The primary end point was all-cause mortality from the date of operation. Multivariable analysis of risk factors for death was performed in the multiphase hazard function domain.
The presence of severe left ventricular hypertrophy at operation, which preceded symptoms in 17% of patients, was associated with decreased survival. This effect was magnified by the severity of aortic stenosis (P = .02) and use of small prostheses (P = .01). The presence of left ventricular dysfunction reduced survival (P = .0003). Although older age was a risk factor for death (P < .0001), elderly patients had survival comparable to their age, race, and sex-matched cohorts, whereas younger patients had worse than expected survival that was further diminished with insertion of a small prosthesis (P = .01).
To optimize survival, earlier aortic valve replacement should be considered even in asymptomatic patients before severe left ventricular hypertrophy or dysfunction develops. In younger patients, the largest possible prosthesis should be implanted to minimize residual gradient; in elderly patients, complex operations just to insert larger prostheses should be avoided.
Full-text · Article · Jun 2008 · The Journal of thoracic and cardiovascular surgery
[Show abstract][Hide abstract] ABSTRACT: Our objective was to quantify incremental risk associated with transfusion of packed red blood cells and other blood components on morbidity after coronary artery bypass grafting.
The study design was an observational cohort study.
This investigation took place at a large tertiary care referral center.
A total of 11,963 patients who underwent isolated coronary artery bypass from January 1, 1995, through July 1, 2002.
Among the 11,963 patients who underwent isolated coronary artery bypass grafting, 5,814 (48.6%) were transfused. Risk-adjusted probability of developing in-hospital mortality and morbidity as a function of red blood cell and blood-component transfusion was modeled using logistic regression. Transfusion of red blood cells was associated with a risk-adjusted increased risk for every postoperative morbid event: mortality (odds ratio [OR], 1.77; 95% confidence interval [CI], 1.67-1.87; p<.0001), renal failure (OR, 2.06; 95% CI, 1.87-2.27; p<.0001), prolonged ventilatory support (OR, 1.79; 95% CI, 1.72-1.86; p<.0001), serious infection (OR, 1.76; 95% CI, 1.68-1.84; p<.0001), cardiac complications (OR, 1.55; 95% CI, 1.47-1.63; p<.0001), and neurologic events (OR, 1.37; 95% CI, 1.30-1.44; p<.0001).
Perioperative red blood cell transfusion is the single factor most reliably associated with increased risk of postoperative morbid events after isolated coronary artery bypass grafting. Each unit of red cells transfused is associated with incrementally increased risk for adverse outcome.
Full-text · Article · Jun 2006 · Critical Care Medicine
[Show abstract][Hide abstract] ABSTRACT: We sought to evaluate magnesium as a neuroprotectant in patients undergoing cardiac surgery with cardiopulmonary bypass.
From February 2002 to September 2003, 350 patients undergoing elective coronary artery bypass grafting, valve surgery, or both were enrolled in a randomized, blinded, placebo-controlled trial to receive either magnesium sulfate to increase plasma levels 1(1/2) to 2 times normal during cardiopulmonary bypass (n = 174) or no intervention (n = 176). Neurologic function, neuropsychologic function, and depression were assessed preoperatively, at 24 and 96 hours after extubation (neurologic) and at 3 months (neuropsychologic, depression). Neurologic scores were analyzed using ordinal longitudinal methods, and neuropsychologic and depression inventory data were summarized by principal component analysis, followed by linear regression analysis using component scores as response variables.
Seven (2%) patients had a postoperative stroke, 2 (1%) in the magnesium and 5 (3%) in the placebo group (P = .4). Neurologic score was worse postoperatively in both groups (P < .0001); however, magnesium group patients performed better than placebo group patients (P = .0001), who had prolonged declines in short-term memory and reemergence of primitive reflexes. Three-month neuropsychologic performance and depression inventory score were generally better than preoperatively, with few differences between groups (P > .6); however, older age (P = .0006), previous stroke (P = .003), and lower education level (P = .0007) were associated with worse performance.
Magnesium administration is safe and improves short-term postoperative neurologic function after cardiac surgery, particularly in preserving short-term memory and cortical control over brainstem functions. However, by 3 months, other factors and not administration of magnesium influence neuropsychologic and depression inventory performance.
No preview · Article · May 2006 · The Journal of thoracic and cardiovascular surgery
[Show abstract][Hide abstract] ABSTRACT: To compare explantation for structural valve deterioration in nonelderly patients after aortic valve replacement with stented bovine pericardial and cryopreserved allograft valves.
From 1981 to 1985, 478 patients received pericardial prostheses during premarket approval; from 1987 to 2000, 744 patients received cryopreserved allografts. Mean age of patients receiving allografts was 49 +/- 12 years, and that of those receiving pericardial prostheses was 65 +/- 11 years; pericardial valves were used in 138 patients younger than age 60. Mean follow-up was 15 +/- 5.1 years for pericardial valves (4674 patient-years of follow-up) and 5.6 +/- 3.1 years for allografts (3892 patient years of follow-up). Multivariable hazard function methodology, age-group stratification, and propensity matching were used to compare age-specific explantation for structural valve deterioration.
Ninety-five pericardial valves and 46 allografts were explanted, and structural valve deterioration was the mechanism of failure in 74% and 59%, respectively. The risk of structural valve deterioration increased with younger age at implantation for both allografts (P = .07) and pericardial valves (P < .0001), with a similar magnitude of effect in patients age 50 years or younger (P = .5), 50 to 60 years (P = .7), and greater than 60 years (P = .9) and in propensity-matched pairs (P = .2). Thus, pericardial valves were as durable as allografts at all adult ages.
Structural valve deterioration is the most frequent cause of valve-related reoperation after both pericardial and allograft aortic valve replacement and is similarly age dependent, suggesting that pericardial valves may be appropriate for nonelderly as well as older persons.
No preview · Article · Mar 2006 · The Journal of thoracic and cardiovascular surgery
[Show abstract][Hide abstract] ABSTRACT: It is unknown whether pulmonary vein isolation or a complete Cox-Maze procedure is needed to ablate paroxysmal atrial fibrillation in patients with mitral valve disease. Our objective was to assess the impact of different surgical treatments for this arrhythmia in patients undergoing mitral valve surgery.
From July 1993 to January 2004, 152 patients underwent combined surgical treatment of paroxysmal atrial fibrillation and mitral valve disease. Ablation procedures included pulmonary vein isolation alone (n = 31, 20%), pulmonary vein isolation with left atrial connecting lesions (n = 80, 53%), and Cox-Maze (n = 41, 27%). The latter had longer durations of atrial fibrillation than the former (p < 0.0001). Rhythm documented on 1,225 postoperative electrocardiograms was used to estimate prevalence of, and risk factors for, atrial fibrillation across time. Ablation failure was defined as occurrence of atrial fibrillation any time beyond 6 months after operation.
Prevalence of postoperative atrial fibrillation peaked at 22% at 2 weeks and declined to 9% at 1 year. Risk factors included older age (p = 0.09), larger left atrium (p = 0.05), and rheumatic (p = 0.003) and degenerative etiologies (p = 0.03). Freedom from ablation failure was 84% at one year. Ablation procedure did not affect prevalence of atrial fibrillation or incidence of ablation failure.
Pulmonary vein isolation alone may be adequate treatment for patients with paroxysmal atrial fibrillation undergoing mitral valve surgery, particularly when it is of short duration. A randomized trial is necessary to examine this strategy, especially in patients with longer duration of paroxysmal atrial fibrillation.
No preview · Article · Feb 2006 · The Annals of thoracic surgery
[Show abstract][Hide abstract] ABSTRACT: The left atrial appendage is a frequent source of thromboemboli in patients with atrial fibrillation. Exclusion or excision of the left atrial appendage may reduce the risk of stroke in patients with atrial fibrillation. We evaluated the ability of a novel device to exclude the left atrial appendage during early and intermediate follow-up periods in a canine model.
Eight mongrel dogs (mean weight 29.1 +/- 4.0 kg) were used in this study. The occlusion device, constructed from 2 stainless steel strips covered with a knit braided polyester fabric, was implanted at the base of the left atrial appendage through a left thoracotomy on a beating heart. Dogs were evaluated at 7 days (n = 2), 30 days (n = 2), and 90 days (n = 4) by epicardial echocardiography, left atrial angiography, histologic inspection, and gross pathology.
Device implantation was performed without complications in all animals. Complete exclusion of the left atrial appendage from the circulation was confirmed acutely and chronically by echocardiographic and angiographic evaluations. There was no device migration or damage to adjacent structures.
This novel device enables rapid, reliable, and safe exclusion of the left atrial appendage. The device provides a new therapeutic option for reducing the risk of stroke in patients with atrial fibrillation.
Full-text · Article · Jan 2006 · The Journal of thoracic and cardiovascular surgery
[Show abstract][Hide abstract] ABSTRACT: Almost 50,000 mitral valve operations are performed annually in the United States, with an increasing number of repairs. Recently, a percutaneous mitral valve repair option that achieves edge-to-edge approximation with a clip has been described in patients with mitral regurgitation.
We describe 6 patients from three centers with mitral regurgitation after percutaneous repair who underwent reintervention. During open surgical revision, the clips were uneventfully removed in all patients with no limitation in surgical options. Five patients underwent repair and 1 underwent replacement.
After surgical revision, mitral regurgitation was significantly decreased, and all but 1 patient underwent uneventful recovery. One patient developed ilio-femoral deep venous thrombosis that was treated successfully with anticoagulation.
Preserving standard of care options is critical with any evolving technology in the event of initial treatment failure. Standard surgical options were preserved in all of the patients who underwent percutaneous mitral valve edge-to-edge repair. Furthermore, a thorough understanding of the clip design, in particular its unlocking mechanism, is essential and facilitates surgical clip removal.
Full-text · Article · Jan 2006 · The Annals of thoracic surgery
[Show abstract][Hide abstract] ABSTRACT: Partial upper sternotomy results in excellent exposure and a safe conduct of a variety of operations on the aortic valve and
ascending aorta. The sternotomy extends into the right fourth intercostal space and is performed through an 8–10 cm long skin
incision. The pericardium is open in the midline and aorta and right atrium are cannulated directly. Aortic valve is exposed
through the oblique aortotomy, after placement of retraction sutures to the commissures. The aortic valve is excised and annulus
meticulously debrided. Aortic valve prosthesis is then inserted into the annulus using a pledgeted non-absorbable suture.
The procedure is performed with the usual surgical instrumentation and can therefore be easily adopted. We discuss the indications,
surgical technique and results of this technique.
Preview · Article · Jan 2006 · Multimedia Manual of Cardiothoracic Surgery
[Show abstract][Hide abstract] ABSTRACT: The Cox maze procedure is the gold standard for ablation of atrial fibrillation in patients undergoing mitral valve surgery, and new approaches to atrial fibrillation ablation must be compared with it. Therefore, we sought to determine the time-related prevalence of atrial fibrillation and its risk factors after combined Cox maze and mitral valve surgery.
From November 1991 through January 2004, 263 patients (mean left atrial diameter, 5.8 +/- 1.2 cm) underwent combined mitral valve surgery (repair in 71%) and a cut-and-sew Cox maze procedure for atrial fibrillation (permanent, 74%; persistent, 7%; paroxysmal, 16%). Rhythm documented on 2367 postoperative electrocardiograms was used to estimate the prevalence of atrial fibrillation across time.
Hospital mortality was 1.9%. Postoperative atrial fibrillation prevalence peaked at 36% at 2 weeks, decreasing to 21% at 5 years. Risk factors for higher postoperative atrial fibrillation prevalence varied with time and included longer duration of preoperative atrial fibrillation (P = .003), larger left atrial diameter (P = .01), older age (P = .0002), and higher left ventricular mass index (P = .02).
In some patients undergoing mitral valve surgery and a Cox maze procedure, atrial fibrillation recurs over time, mandating close, long-term follow-up of heart rhythm. Earlier operation and left atrial size reduction should be considered to improve results in selected patients.
No preview · Article · Jan 2006 · The Journal of thoracic and cardiovascular surgery
[Show abstract][Hide abstract] ABSTRACT: Background Biventricular (BiV) pacing is a proven advantageous adjuvant therapy for patients with ventricular dyssynchrony associated with congestive heart failure. Endocardial left ventricular lead placement does have several limitations: 1) anatomic variations of the coronary venous system, 2) late lead dislodgement, and 3) phrenic/diaphragmatic stimulation. Epicardial lead placement is often a ‘rescue’ procedure after failed coronary sinus implantation but offers some advantages related to safety and a shorter implant time. The aim the study is to describe two different minimally invasive surgical techniques for LV epicardial lead placement for resynchronization therapy of patients with chronic heart failure.
Methods Between December 2002 and December 2004, 88 patients (pts) underwent minimally invasive left ventricular lead placement, Videoendoscopic assisted surgery was performed in patients 31, and Minithoracotomy in 57. Fifty pts. (56.8%) were males, mean age was 67 ±8.3 years (35-83), 44 (54.5%) had previous cardiac surgery, 58 (66%) had ischemic cardiomyopathy, 20 (22.7%) NYHA III-IV, 31 (35%) had more than 3+ mitral regurgitation and 46 (52.3%) had implantable cardioverter defibrillators.
Results There were no deaths. The mean hospital length of stay was 4.5 ± 3.2 days. Postoperative complications included non-dialysis renal failure in 4 pts. (4.5%), atrial fibrillation in 10 (11.3%), non sustained ventricular tachycardia in 3 (3.4%) and decompensate heart failure in 2 (6.2%). Significant improvements were observed in postoperative parameters in comparison to the preoperative period (Table).
Conclusions Minimally invasive LV epicardial lead placement are effective and safety techniques, with minimal morbidity, and can be helpful in the treatment of this complex disease. Prospective randomized studies between epicardial and endocardial lead placements should further define the role of these different techniques in the resynchronization therapy for heart failure.
[Show abstract][Hide abstract] ABSTRACT: With traditional mitral valve repair techniques, prolapse at a commissure presents a surgical challenge. When commissural prolapse is identified, simple closure of the commissure combined with annuloplasty enables rapid and reliable mitral valve repair.
Full-text · Article · Oct 2005 · The Annals of thoracic surgery
[Show abstract][Hide abstract] ABSTRACT: Ischemic mitral regurgitation (MR) is associated with poor survival and degenerative MR with excellent survival. We hypothesized that in some patients with degenerative MR requiring concomitant coronary artery bypass grafting (CABG), ischemic disease would dominate prognosis, resulting in survival as poor as in patients with ischemic MR. Thus, we (1) determined survival impact of etiology (degenerative vs ischemic) after combined mitral valve repair and CABG and (2) explored survival differences within etiology groups.
From 1985 to 2003, 710 patients underwent mitral valve repair for degenerative MR and concomitant CABG (two diseases); 400 patients had mitral annuloplasty and CABG for functional ischemic MR (one disease). Patients were propensity-matched on demography, symptoms, comorbidities, coronary artery disease, and left ventricular function. Survival was compared between matched groups and within groups.
Compared with patients with degenerative MR, those with ischemic MR had more extensive coronary artery disease, worse ventricular function, more comorbidities, and more symptoms (p < 0.05). Unadjusted 5-year survivals were 64% and 82% for patients with ischemic and degenerative MR, respectively. However, 123 ischemic and degenerative MR matched pairs had equivalently poor 5-year survival (p > 0.9), 66% and 65%, respectively. Among patients with degenerative MR, survival varied widely, depending largely on ischemic burden and extent of left ventricular dysfunction.
The large survival discrepancy between patients with ischemic and degenerative MR is attributable to differences in patient profile, particularly extent of ischemic disease and left ventricular dysfunction. Thus, ischemic and degenerative MR patients with equivalent characteristics have equivalently poor survival.
Full-text · Article · Oct 2005 · The Annals of thoracic surgery
[Show abstract][Hide abstract] ABSTRACT: In studying cardiac surgical patients undergoing atrial fibrillation ablation with bipolar radiofrequency, we sought to (1) quantify the time-related prevalence of atrial fibrillation postoperatively and identify its risk factors and (2) determine time-related ablation failure and its risk factors.
From November 2001 to January 2004, 513 patients underwent atrial fibrillation ablation (bipolar radiofrequency alone or with cryothermy) and other cardiac operations. Rhythm documented on 3495 postoperative electrocardiograms was used to estimate the prevalence of and risk factors for atrial fibrillation across time. Ablation failure was defined as occurrence of atrial fibrillation any time beyond 6 months after operation.
Prevalence of postoperative atrial fibrillation peaked at about 1 month, decreased to 13% at 6 months, and gradually increased thereafter. Risk factors associated with increased prevalence varied by time period and included older age ( P = .004) for early occurrence, lesion set in permanent atrial fibrillation ( P = .02) for late occurrence, and larger left atrial diameter ( P = .02) and permanent atrial fibrillation ( P < .0001) for occurrence across the entire time span. Freedom from ablation failure was 72% at 12 months. Risk factors for ablation failure included lesion set in permanent atrial fibrillation ( P = .001), longer duration of atrial fibrillation ( P = .01), and larger left atrial diameter ( P = .03).
Bipolar radiofrequency enables extension of ablation to most cardiac surgical patients with atrial fibrillation. Recurrence is influenced by the type and duration of atrial fibrillation, choice of lesion set in permanent atrial fibrillation, and left atrial size. Early operation, careful choice of lesion set, and left atrial reduction might enhance results.
No preview · Article · Jul 2005 · Journal of Thoracic and Cardiovascular Surgery
[Show abstract][Hide abstract] ABSTRACT: Epicardial lead placement for biventricular pacing is often a rescue procedure after failed coronary sinus cannulation. This study aims to determine perioperative and early postoperative outcome of minimally invasive left ventricular lead placement as a management strategy for heart failure, comparing minithoracotomy and endoscopic approaches.
From October 2002 through October 2003, 41 patients underwent minimally invasive left ventricular lead placement, 23 (56%) by minithoracotomy and 18 (44%) endoscopically. Thirty-one (76%) were males, 19 (46%) had previous cardiac surgery, 21 (51%) had ischemic cardiomyopathy, 17 (41%) were in New York Heart Association class III or IV, and 28 (65%) had implantable cardioverter-defibrillators.
There were no in-hospital deaths, intraoperative complications, or failures to implant the left ventricular lead. Median operative time was longer for the endoscopic approach (188 minutes) than for minithoracotomy (151 minutes; p = 0.006). Preoperatively, the endoscopic group had more mitral regurgitation (median, 2.5 versus 1.0, respectively; p = 0.009). QRS duration was shorter postoperatively (mean change from preoperative, -32 +/- 24 ms; p < 0.0001); this change was unrelated to surgical approach. Impedance also was less postoperatively (mean change, -490 +/- 300 ohms; p < 0.0001), and the change was unrelated to surgical approach. Changes were greater the larger their preoperative values (p < 0.0001). Threshold increased with follow-up time (adjusted p < 0.0001), but impedance decreased (adjusted p = 0.0009); these trends were similar for both approaches. No changes were evident in left ventricular dimensions.
Minimally invasive left ventricular epicardial lead placement is safe and effective, offering selection of the best pacing site with minimal morbidity; it can be considered a primary option for resynchronization therapy.
Full-text · Article · Jun 2005 · The Annals of thoracic surgery
[Show abstract][Hide abstract] ABSTRACT: There is increasing interest in the role of valve repair for patients with isolated severe aortic regurgitation. Those with bicuspid aortic valves are suggested as most suitable for repair. Morphologic features of these valves that suggest feasibility of repair are not well defined.
Perioperative echocardiograms on 132 consecutive patients (mean age 42 +/- 12 years; 94% male), with bicuspid valves and isolated aortic regurgitation undergoing surgery at our institution were reviewed. Seventy-five patients (57%) underwent successful valve repair. Repair was attempted but unsuccessful for another 8 patients (6 intraoperatively and 2 before discharge).
Cusp prolapse was the most common primary mechanism of regurgitation (88 patients [67%]), with 81 patients having primarily eccentrically directed regurgitation. Echocardiographic examination of 72 (55%) had evidence of cusp thickening with 40 (30%) having cusp calcification. By multivariate analysis, an eccentric regurgitant jet direction (odds ratio = 14.3; 95% confidence interval [CI] = 3.4 to 59.6), lack of cusp thickening (odds ratio = 5.9 [1.7 to 20]), lack of cusp calcification (odds ratio = 4.2; [1.1 to 16.7]) and the absence of commissural thickening (odds ratio = 4.8 [1.3 to 16.7]) were independently associated with a greater likelihood of successful valve repair. Greater cusp thickening was the only factor associated with attempted but failed repair.
Successful repair of regurgitant bicuspid aortic valves was more feasible for those patients with eccentric regurgitant jets, those without cusp or commissural thickening or cusp calcification. Recognition of these features may enhance patient selection and improve procedural outcomes with aortic valve repair.
Preview · Article · Jun 2005 · The Annals of thoracic surgery