Faculty Bibliography

BACKGROUND: Paradoxical septal motion (PSM) is the systolic movement of the interventricular septum toward the right ventricle despite normal thickening. The PSM is a frequent echocardiographic finding after cardiac surgery. Although it is universally recognized, there has been no large-scale study to correlate PSM with the type of surgical procedure. The cause of PSM is unknown; prevailing theories include: (1) operation on the heart alters the degree to which it is restrained by the pericardium and the chest wall and (2) transient ischemia alters septal motion. HYPOTHESIS: The PSM is related to type of surgery and surgical approach. METHODS: Between 1996 and 2002, 3,292 patients underwent a first cardiac operation and had a postoperative echocardiogram; 313 were excluded due to other explanations for PSM (severe tricuspid regurgitation [TR] cardiac pacing), leaving a study group of 2,979 patients. Univariate and multivariate analyses were performed to determine which surgical characteristics were correlated with postoperative PSM. Septal thickening was assessed in a subset. RESULTS: On multivariate analysis, aortic (p = 0.02) and mitral valve surgery (p < 0.001) and longer cardiopulmonary bypass time (p < 0.001) were independently associated with PSM. Coronary artery bypass grafting (CABG) was less likely to cause PSM than non-CABG surgery (p = 0.003) and off-pump coronary artery bypass (OPCAB) caused less PSM than did on-pump CABG. CONCLUSIONS: 1. Valve surgery is more likely to cause PSM than CABG. 2. Among patients with CABG, OPCAB causes less PSM. 3. Cardiopulmonary bypass time is associated with the development of PSM. 4. The cause of PSM is likely to be multifactorial

Chronic heart failure (CHF) has become an epidemic in the United States, with approximately 550,000 new cases annually. With the evolution of pharmacotherapy targeting neurohormonal pathways, the annual mortality in subjects with New York Heart Association (NYHA) class IV CHF has dramatically improved from 52% in the seminal CONSENSUS trial to less than 20% in more recent trials. Suppression of the renin-angiotensin-aldosterone system remains the first line of neurohormonal blockade followed by the addition of selective beta-adrenoreceptor blockers. For patients with NYHA class I and II symptoms, mortality rates have decreased to approximately 5% or less per year with the use of angiotensin-converting enzyme inhibitors, beta-blockers and aldosterone receptor blockers. However, after achieving optimal doses of the indicated pharmacotherapy, and despite the additional benefits obtained with biventricular pacemakers, there are still many patients who continue to experience signs and symptoms of CHF. Recognizing the beneficial effects of the above treatments on left ventricular (LV) remodeling, strategies have been developed to surgically reshape the left ventricle in patients with LV dilation who have associated poor LV function. This review will discuss the techniques and recent developments regarding surgical reshaping of the dilated, dysfunctional, and remodeled left ventricle

BACKGROUND: Mild and moderate functional ischemic mitral insufficiency present at the time of surgical revascularization present clinical uncertainty. It is unclear whether the relatively poor outcomes in this cohort are dependent on valvular function or related to left ventricular dysfunction. The purpose of this study was to examine the early and late outcomes in patients with less-than-severe functional ischemic mitral insufficiency at the time of isolated coronary artery bypass grafting (CABG). METHODS AND RESULTS: From 1996 through 2004, 2242 consecutive patients undergoing isolated CABG were identified as having none to moderate mitral regurgitation (MR) and no valve leaflet pathology. All of the patients at this single institution routinely had an intraoperative transesophageal echocardiography, prospectively quantified MR, and ejection fraction (EF). The New York State Cardiac Surgery Reporting System infrastructure was used to prospectively collect in-hospital patient variables and outcomes. Social Security Death Benefit Index was used to determine long-term survival. Odds ratio and significance (P value) are presented for each determined risk factor. There were 841 patients (37.5%) with no MR, 1137 (50.7%) with mild MR, and 264 (11.8%) with moderate MR. The patients with moderate MR were more likely to be older, female, and have more renal disease, previous MI, congestive heart failure, previous cardiac surgery, and lower EFs. Hospital mortality was independently and significantly associated with renal disease, decreasing EF, increasing age, previous cardiac operation, and cerebral vascular disease. Multivariable analysis revealed decreased survival with increasing age, previous operation, congestive heart failure, diabetes, nonelective operation, decreasing EF, and the presence of moderate MR (expbeta = 1.49; P=0.007) and mild MR (expbeta = 1.34; P=0.033). CONCLUSIONS: Independent of ventricular function, mild and moderate functional mitral insufficiency are associated with significantly decreased survival in patients undergoing CABG. Whether correction of moderate functional MR at the time of CABG improves outcome still needs to be determined

BACKGROUND: Functional mitral regurgitation is associated with both annular and ventricular distortion. Aggressive reduction annuloplasty for functional mitral regurgitation acts primarily at the annulus, with variable impact on the left ventricle. The Coapsys device externally reshapes the left ventricle to correct functional mitral regurgitation. Left ventricular reshaping was analyzed in a randomized study. METHODS: The RESTOR-MV study randomizes patients with coronary artery disease and functional mitral regurgitation to either reduction annuloplasty and coronary artery bypass grafting (the RA group) or Coapsys annuloplasty and bypass grafting (the CO group). The Coapsys device consists of epicardial pads connected by a cord. It was placed without cardiopulmonary bypass under echocardiographic guidance and sized to reduce annular dimension and improve leaflet coaptation. Internal reduction annuloplasty was performed by device placement. Intraoperative transesophageal echocardiograms were analyzed in 7 patients having reduction annuloplasty and 7 having Coapsys annuloplasty. RESULTS: Baseline mitral regurgitation (0-4 scale) was similar for the RA (3.0 +/- 0.6) and the CO groups (3.0 +/- 0.6). Intraoperative mitral regurgitation was reduced from 2.86 +/- 0.7 to 0.5 +/- 0.7 (P < .01 pre vs post) for the RA group and from 2.64 +/- 0.9 to 05 +/- 0.7 (P < .01 pre vs post) for the CO group. Annular anteroposterior diameter was reduced with both techniques: RA, 3.45 +/- 0.39 to 2.34 +/- 0.37 cm (P < .01 pre vs post); CO, 3.40 +/- 0.27 to 2.85 +/- 0.34 cm (P < .05 pre vs post). Long-axis dimensions were unchanged with both techniques. Short-axis dimensions measured at three levels were significantly reduced only in the CO patients: basal diameter 4.77 +/- 0.58 to 3.58 +/- 0.38 cm (P < .01 pre vs post); mid diameter 4.88 +/- 0.55 to 3.57 +/- 0.43 cm (P < .01 pre vs post); and apical diameter 4.39 +/- 0.46 to 3.38 +/- 0.34 cm (P < .01 pre vs post). CONCLUSIONS: Coapsys and reduction annuloplasty techniques both acutely reduce functional mitral regurgitation and annular dimension. The Coapsys device provided significantly greater left ventricular reshaping than did reduction annuloplasty. Further evaluation will assess the long-term valvular function and ventricular geometric stability associated with both techniques

OBJECTIVE: Minimally invasive, nonsternotomy approaches for valve procedures may reduce the risks associated with cardiac surgery after prior sternotomy and may improve outcomes. We analyzed our institutional experience to test this hypothesis. METHODS: Between 1995 and 2002, 498 patients with previous cardiac operations via sternotomy underwent isolated valve surgery: 337 via median sternotomy (aortic = 160; mitral = 177) and 161 via mini-thoracotomy (aortic = 61; mitral = 100). Data were collected prospectively using the New York State Cardiac Surgery Report Form. RESULTS: Preoperative incidences of congestive heart failure, renal disease, and nonelective procedures were higher in the sternotomy group. Hospital mortality was significantly lower with the minimally invasive approach, 5.6% (9/161) versus 11.3% (38/337) (univariate, p = 0.04). However, multivariate analysis (odds ratio: 95% confidence intervals, p value) revealed that chronic obstructive pulmonary disease (6.6: 1.4 to 3.1, p = 0.001), renal disease (4.1: 1.52 to 11.2, p = 0.01), cerebrovascular disease (2.2: 1.03 to 4.78, p = 0.04), and ejection faction <30% (1.5: 0.96 to 5.5, p = 0.06) were associated with increased mortality. While mean bypass time, cross-clamp times, and stroke rates were comparable between groups, patients undergoing minimally invasive valve surgery had no deep wound infections (0% vs 2.4%, p = 0.05), less need for blood products (p = 0.02), and shorter hospital stays (p = 0.009). Five-year survival was higher with minimally invasive techniques as compared to a sternotomy approach (92.4 +/- 2% and 86.0 +/- 2%, respectively, p = 0.08). CONCLUSIONS: Reoperative valve surgery can be safely performed using a nonsternotomy, minimally invasive approach, with at least equal mortality, less hospital morbidity, decreased hospital length of stay, and slightly favorable mid-term survival as compared to sternotomy

Matrix metalloproteinases (MMPs) play key roles in vascular remodeling. We characterized the role of inflammatory mediators and extracellular signal-regulated kinases (ERKs) in the control of arterialized vein graft expression of MMP-9, MMP-2, and membrane-type 1-MMP (MT1-MMP) and of the tissue inhibitor of metalloproteinases-2 (TIMP-2). For this purpose we used a canine model of jugular vein to carotid artery interposition graft and analyzed the vein grafts at various postoperative times (30 min to 28 days) using the contralateral vein as a control. To study the role of ERK-1/2, veins were incubated with the mitogen-activated protein kinase kinase (MEK-1/2) inhibitor UO126 for 30 min before being grafted. Vein graft extracts were analyzed for MMPs, TIMP-2, tumor necrosis factor-alpha (TNF-alpha), polymorphonuclear neutrophil (PMN) infiltration, myeloperoxidase (MPO), and thrombin activity, and for ERK-1/2 activation. Vein graft arterialization resulted in rapid and sustained (8 h to 28 days) upregulation of vein graft-associated MMP-9, MMP-2, MT1-MMP, thrombin activity, and TNF-alpha levels with concomitant TIMP-2 downregulation. MMP-2 activation preceded MT1-MMP upregulation. PMN infiltration and vein graft-associated MPO activity increased within hours after arterialization, indicating a prompt, local inflammatory response. In cultured smooth muscle cells, both thrombin and TNF-alpha upregulated MT1-MMP expression; however, only thrombin activated MMP-2. Inhibition of ERK-1/2 activation blocked arterialization-induced upregulation of MMP-2, MMP-9, and MT1-MMP. Thus, thrombin, inflammatory mediators, and activation of the ERK-1/2 pathway control MMP and TIMP-2 expression in arterialized vein grafts

BACKGROUND: Functional ischemic mitral regurgitation (MR) frequently arises after myocardial infarction; it is characterized by annular enlargement or lateral displacement of the subvalvular apparatus. Coapsys is a ventricular-annular remodeling device designed to treat functional ischemic MR; it does not require cardiopulmonary bypass. Initial intraoperative results of the RESTOR-MV randomized clinical trial are presented. METHODS: Patients referred for coronary artery bypass grafting with preoperative MR grade of 2 or greater were studied, excluding those with structural valve abnormalities. The Coapsys device, which consists of two epicardial pads connected by a flexible cord, was surgically implanted in 19 patients. Under epicardial echocardiographic guidance, the cord was passed through the left ventricle and tightened externally to improve leaflet coaptation and stabilize the ventricular wall; tightening was conducted with color flow Doppler imaging. RESULTS: Patients were 64.5 +/- 9.2 years old with an ejection fraction of 0.383 +/- 0.089 and received 2.7 +/- 1.1 grafts. Intraoperative MR grade was 2.7 +/- 0.8 after induction and was reduced to 0.4 +/- 0.7 after implantation (p < 0.0001). Mean epicardial dimension was reduced from 8.5 +/- 1.2 to 6.4 +/- 0.9 cm (p < 0.0001). Intraoperative MR was reduced in 95% (18 of 19) of patients, and 84% (16 of 19) had MR grade 1 or less after implantation. All implants were performed without cardiopulmonary bypass or conversion to standard annuloplasty. No hemodynamic compromise or structural damage to the mitral apparatus was noted. Significant acute remodeling was noted in the left ventricular dimensions. CONCLUSIONS: In patients without structural valve disease, the Coapsys device acutely reduces functional MR. Further randomized evaluation will assess long-term stability and compare it with standard annuloplasty techniques