Novel assessment of intestinal anastomotic perfusion using ICG SPY in a continuous flow LVAD patient.

HeartMate II left ventricular assist device (LVAD) assists heart failure patients by generating continuous flow via axial flow pump placed in the left ventricle. Little is known of the effect of continuous flow on intestinal anastomoses. This is the first case visually documenting altered perfusion patterns in patients with LVADs using indocyanine green (ICG). A 72-year-old male required a colon resection, for adenocarcinoma, following implantation of an LVAD. Perfusion of the anastomosis was evaluated using indocyanine. During the assessment, an unusual perfusion pattern was noticed. Normally, flow as measured by SPY is seen as an initial blush of contrast followed by a gradual, pulsatile increase in the progression of the indocyanine through the tissues. In this patient, instead of the usual initial blush, a continuous beam of ICG was seen to flow though the blood vessels. This novel perfusion pattern is consistent with flow generated from LVAD.

Venous Stent Migrating to the Right Heart Causing Severe Regurgitation.

Venous stent migration to the cardiopulmonary system is a rare but serious complication. Cardiopulmonary involvement has various presentations such as valvulopathy, acute heart failure, arrhythmias, endocarditis, and tamponade. The presenting symptoms depend on the eventual location of the stent in the heart or lungs, size of the stent, and valve involvement. Extracardiac dislodgement can be managed by catheter-directed extraction or proper deployment within the containing vessel or surgical extraction. Intracardiac stents may require open surgery to prevent life-threatening complications. We present an asymptomatic patient with stent migration that lead to severe tricuspid regurgitation and required tricuspid valve replacement.

Acute Respiratory Distress Syndrome Requiring Extracorporeal Membrane Oxygenation as the Initial Presentation of Anti-neutrophillic Cytoplasmic Auto-antibody Positive Vasculitis.

Acute respiratory distress syndrome (ARDS) is a life-threatening inflammatory state of lung injury that can require acute interventions including mechanical ventilation as well as emergent veno-venous extracorporeal membrane oxygenation (VV-ECMO) for management. Etiologies of ARDS are not clearly discernible in certain cases and can vary from sepsis, pneumonia, trauma and intoxication. Anti-nuclear cytoplasmic auto-antibody (ANCA)-associated vasculitis (AAV) is a group of several conditions that can have pulmonary complications including ARDS. We present a case where the primary manifestation of myeloperoxidase (MPO)-ANCA positive vasculitis was ARDS, in order to highlight the importance of investigating rare vasculitides as the underlying cause of ARDS and the importance of ECMO as an early life-saving intervention for the management of ARDS.

Peripheral extracorporeal membrane oxygenation: comprehensive therapy for high-risk massive pulmonary embolism.

BACKGROUND: Although commonly reserved as a last line of defense, experienced centers have reported excellent results with pulmonary embolectomy for massive and submassive pulmonary embolism (PE). We present a contemporary surgical series for PE that demonstrates the utility of peripheral extracorporeal membrane oxygenation (pECMO) for high-risk surgical candidates. METHODS: Between June 2005 and April 2011, 29 patients were treated for massive or submassive pulmonary embolism, with surgical embolectomy performed in 26. Four high-risk patients were placed on pECMO, established by percutaneously cannulating the right atrium through a femoral vein and perfusing by a Dacron graft anastomosed to the axillary artery. A small, extracorporeal, rotary assist device was used, interposing a compact oxygenator in the circuit, and maintaining anticoagulation with heparin. RESULTS: Extracorporeal membrane oxygenation was weaned in 3 of 4 patients after 5.3 days (5, 5, and 6), with normalization of right ventricular dysfunction and pulmonary artery pressure (44.0 ± 2.0 to 24.5 ± 5.5 mm Hg) by ECHO. Follow-up computed tomographies showed several peripheral, nearly resorbed emboli in 1 case and complete resolution in 2 others. The fourth patient, not improving after 10 days, underwent surgery where an embolic liposarcoma was extracted. For all 29 cases, hospital and 30-day mortality was 0% and all patients were discharged, with average postoperative length of stay of 15 days for embolectomy and 17 days for pECMO. CONCLUSIONS: Heparin therapy with pECMO support is a rapid, effective option for patients who might benefit from pulmonary embolectomy but are at high risk for surgery.

The completion Bentall procedure.

Patients that have undergone aortic valve replacement may subsequently present with an aortic root aneurysm, but with a normally functioning prosthetic valve. We describe our method of replacing the aortic root while retaining the existing aortic valve as the "completion Bentall procedure."

Acute aortic syndrome.

The term acute aortic syndrome refers to a heterogeneous group of conditions that cause a common set of signs and symptoms, the foremost of which is aortic pain. Various pathologic entities may give rise to this syndrome, but the topic has come to focus on penetrating aortic ulcer and intramural hematoma and their relation to aortic dissection. Penetrating aortic ulcer is a focal atherosclerotic plaque that corrodes a variable depth through the intima into the media. Intramural hematoma is a blood collection within the aortic wall not freely communicating with the aortic lumen, with restricted flow. It may represent a subcategory of aortic dissection that manifests different behavior by virtue of limited flow in the false lumen. This article reviews the current literature regarding acute aortic syndrome, focusing on management options.

Minimally invasive reoperative isolated valve surgery: early and mid-term results.

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.

Mechanisms of c-reactive protein up-regulation in arterialized vein grafts.

BACKGROUND: C-reactive protein (CRP), an acute phase reactant, is an independent predictor of coronary artery syndromes and a mediator of the vascular response to injury. CRP has been found in arterialized vein grafts and has been linked to atherogenesis; however, its involvement in vein graft early failure or intimal hyperplasia has not been assessed. This study was designed to investigate the mechanism(s) of CRP up-regulation in arterialized vein grafts. METHODS: Carotid artery bypass with arterialized jugular vein grafts (AVG) was performed in 18 dogs. AVG were harvested at 3, 8, and 24 hours and 4, 14, and 28 days, using the femoral vein obtained at the time of AVG harvest as a control. Serum CRP levels were characterized by enzyme-linked immunosorbent assay; AVG expression of CRP was studied by immunofluorescence, Western blotting, in situ hybridization, Northern blotting, and quantitative RT-PCR. RESULTS: CRP levels peaked at 24 hours in serum and AVG but remained at baseline in control veins. By double immunofluorescence, CRP was associated with the media and adventitia of AVG. However, Northern blotting analysis showed no CRP mRNA expression in AVG. Reverse transcriptase polymerase chain reaction analysis confirmed the lack of up-regulation of CRP in AVG. CONCLUSION: CRP levels are increased in AVG, peaking 24 hours after arterialization. However, no significant production of CRP was detected in AVG. Therefore, increased CRP levels within AVG appear to originate mostly from CRP diffusion from the systemic circulation. These results have significant implications for the development of strategies aimed at blocking CRP up-regulation in bypass grafts.

Matrix metalloproteinase expression in vein grafts: role of inflammatory mediators and extracellular signal-regulated kinases-1 and -2.

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.

Anti-proliferative and anti-inflammatory effects of topical MAPK inhibition in arterialized vein grafts.

Vein graft failure following bypass surgery is a frequent and important clinical problem. The vascular injury caused by arterialization is responsible for vein graft intimal hyperplasia, a lesion generated by medial smooth muscle cell proliferation and migration into the intima, increased extracellular matrix deposition, and formation of a thick neointima. Development of the neointima into a typical atherosclerotic lesion and consequent stenosis ultimately result in vein graft failure. Endothelial damage, inflammation, and intracellular signaling through mitogen-activated protein kinases (MAPKs) have been implicated in the early stages of this process. We therefore investigated the effects of topical inhibition of ERK-1/2 MAPK activation on vascular cell proliferation and apoptosis, and on the inflammatory response in a canine model of vein graft arterialization. For this purpose, vein grafts were incubated with the MEK-1/2 inhibitor, UO126, ex vivo for 30 min before grafting. This treatment effectively abolished arterialization-induced ERK-1/2 activation, decreased medial cell proliferation, and increased apoptosis. UO126 treatment also inhibited the vein graft infiltration by myeloperoxidase-positive inflammatory cells that follows vein graft arterialization. Thus, topical ex vivo administration of MAPK inhibitors can provide a pharmacological tool to prevent or reduce the vascular cell responses that lead to vein graft intimal hyperplasia and graft failure.

Intraoperative effects of the coapsys annuloplasty system in a randomized evaluation (RESTOR-MV) of functional ischemic mitral regurgitation.

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.

Localized pericardial hematoma presenting with acute hypoxemia.

Localized pericardial hematomas after cardiac surgery may have atypical clinical presentations due to regional alterations in cardiac function and hemodynamics. We report a case of extravascular thrombus that compressed the main pulmonary artery and produced acute hypoxemia due to right-to-left shunting across a patent foramen ovale. We review the pathophysiology leading to this finding and the echocardiographic studies that established the diagnosis.

Propensity score analysis of a six-year experience with minimally invasive isolated aortic valve replacement.

BACKGROUND AND AIM OF THE STUDY: Although minimally invasive aortic valve replacement (MIAVR) is becoming an accepted technique, additional outcome evaluation is required. To correct for non-randomized treatment, the propensity score was used to analyze the present authors' experience with MIAVR compared to standard sternotomy (SS). METHODS: Between January 1995 and December 2002, a total of 921 consecutive patients underwent isolated AVR; 438 of these patients had MIAVR. Two matched cohorts each of 233 patients, and with comparable distributions of risk factors, were constructed using propensity analysis of prospectively collected data. Matching variables included left ventricular ejection fraction <30%, previous myocardial infarction, congestive heart failure, previous cardiac surgery, renal insufficiency, age, gender, chronic obstructive pulmonary disease (COPD), peripheral vascular disease, previous stroke or carotid disease, urgent/emergent operation, valvular pathophysiology, and atheromatous aortic disease. RESULTS: Hospital mortality and major morbidity were similar in the MIAVR and SS groups: 5.6% versus 7.3% (p = 0.45) and 13.3% versus 14.2% (p = 0.79), respectively. Multivariable analysis of all patients revealed increased mortality with severe atheromatous aortic disease (p = 0.001), COPD (p = 0.002), and urgent operation (p = 0.02). Freedom from any major perioperative morbidity was similar in both groups (86.7% versus 85.8%; p = 0.79). However, the median length of stay was shorter with MIAVR (6 versus 8 days; p <0.001). During the past three years, a greater percentage of MIAVR patients than SS patients was discharged home rather than sent to rehabilitation facilities or nursing homes (65.7% versus 52.9%; p = 0.05). CONCLUSION: MIAVR can be performed safely, with morbidity and mortality outcomes similar to those of standard sternotomy. MIAVR is associated with a decreased length of hospital stay, and a greater proportion of patients are discharged home directly.

Anterior leaflet resection of the mitral valve.

Triangular resection is a reconstructive option for treatment of anterior leaflet mitral disease with segmental prolapse. In our experience, it is a safe and reproducible technique, associated with low rates of recurrent MR or need for reoperation, as well as decreased likelihood for systolic anterior motion after mitral repair. We review our experience with this technique over a 25-year experience with mitral valve reconstruction.

Vein graft arterialization causes differential activation of mitogen-activated protein kinases.

OBJECTIVE: Vascular injury results in activation of the mitogen-activated protein kinases-extracellular-signal regulated kinases, c-jun N-terminal kinase, and p38(MAPK)-which have been implicated in cell proliferation, migration, and apoptosis. The goal of this study was to characterize mitogen-activated protein kinase activation in arterialized vein grafts. METHODS: Carotid artery bypass using reversed external jugular vein was performed in 29 dogs. Vein grafts were harvested after 30 minutes and 3, 8, and 24 hours, and 4, 7, 14, and 28 days. Contralateral external jugular vein and external jugular vein interposition vein-to-vein grafts were used as controls. Vein graft extracts were analyzed for extracellular-signal regulated kinases, c-jun N-terminal kinase, and p38(MAPK) activation. Proliferating cell nuclear antigen expression was investigated as a parameter of cell proliferation. Apoptosis was assessed by terminal deoxynucleotidyl transferase-mediated 2'-deoxyuridine 5'-triphosphate nick end labeling staining and intimal hyperplasia by morphometric examination of tissue sections. RESULTS: Significant intimal hyperplasia was observed at 28 days. Over the time points studied, vein graft arterialization resulted in bimodal activation of both extracellular-signal regulated kinase and p38(MAPK) (30 minutes through 3 hours; 4 days) but did not induce activation of c-jun N-terminal kinase. Proliferating cell nuclear antigen expression increased from days 1 through 28, and apoptosis increased between 8 and 24 hours. CONCLUSION: Vein graft arterialization induces bimodal activation of extracellular-signal regulated kinase and p38(MAPK); however, in contrast with what is described in arterial injury, it does not induce c-jun N-terminal kinase activation. These results provide the first comprehensive characterization of the mitogen-activated protein kinase signaling pathways activated in vein graft arterialization and identify mitogen-activated protein kinases as potential mediators of vein graft remodeling and subsequent intimal hyperplasia.

Minimally invasive technology for mitral valve surgery via left thoracotomy: experience with forty cases.

BACKGROUND: Recent evolution of minimally invasive technology has expanded the application of the right thoracotomy approach for mitral valve surgery. These same technological advances have also made the left posterior minithoracotomy approach attractive in complex mitral procedures. METHODS: From 1996 to 2003, 921 isolated mitral valve procedures were performed without sternotomy; 40 (4.3%) of these were performed via left posterior minithoracotomy. In the left posterior minithoracotomy group, ages ranged from 18 to 84 years; 36 patients had had previous cardiac surgery (9 on > or =2 occasions). Other factors precluding right thoracotomy included mastectomy/radiation and pectus excavatum. RESULTS: Arterial perfusion was via femoral artery (n = 26) or descending aorta (n = 14); long femoral venous cannulas with vacuum-assisted drainage were used in 39 procedures. Two patients had direct aortic crossclamping, 18 had hypothermic fibrillation, and 20 had balloon endoaortic occlusion. The mean crossclamp and bypass times were 81.9 and 117.2 minutes, respectively. Hospital mortality was 5.0% (2/40); both deaths occurred in octogenarians. There were no injuries to bypass grafts or conversions to sternotomy. Complications included perioperative stroke (2/40; 5.0%), bleeding (2/40; 5.0%), and respiratory failure (1/40; 2.5%); 28 patients (70%) had no postoperative complications. There was no incidence of perioperative myocardial infarction, renal failure, sepsis, or wound infection. The median length of stay was 7 days. CONCLUSIONS: Advances in minimally invasive cardiac surgery technology are readily adaptable to a left-sided minithoracotomy approach to the mitral valve. The left posterior minithoracotomy approach is a valuable option in complicated reoperative mitral procedures with acceptable perioperative morbidity and mortality.

Semirigid partial annuloplasty band allows dynamic mitral annular motion and minimizes valvular gradients: an echocardiographic study.

BACKGROUND: Traditional mitral annuloplasty devices include both rigid rings, which restrict annular motion, and soft rings and bands, which can locally deform. Conflicting data exist regarding their impact on annular dynamics. We studied mitral annuloplasty with a semirigid partial band and with a nearly complete rigid ring. METHODS: Intraoperative three-dimensional transesophageal echocardiograms (n = 14) and predischarge transthoracic echocardiograms were retrospectively analyzed in patients undergoing mitral valve repair for degenerative disease with either a rigid ring (n = 77) or a semirigid partial band (n = 38). Each transesophageal echocardiogram was analyzed with TomTec three-dimensional software to produce cardiac cycle frame planimetry and to measure device geometry. Actual device sizes provided reference dimensions. Blinded analysis of Doppler data from transthoracic echocardiograms was performed. RESULTS: Validation of the quantitative transesophageal echocardiogram methodology revealed a 1.3% +/- 0.3% (mean +/- standard error of the mean) underestimation of actual linear dimension. With the semirigid partial band, systolic valve orifice area and intertrigonal distance decreased from 6.14 +/- 0.37 to 5.55 +/- 0.24 cm(2) (-9.6%; p = 0.01) and from 2.69 +/- 0.08 to 2.55 +/- 0.13 cm (-5.2%; p = 0.03), respectively. Systolic anterior-posterior distance decreased from 2.1 +/- 0.10 to 1.95 +/- 0.06 cm (-7.1%; p = 0.01) compared with diastole. In contrast, rigid ring orifice area was unchanged (4.12 +/- 0.15 to 4.10 +/- 0.16 cm(2); -0.5%; p = 0.48) during the cardiac cycle. Transthoracic echocardiography revealed significantly lower mitral inflow gradients with semirigid partial band (mean gradients compared with rigid ring, 4.0 +/- 0.3 versus 5.0 +/- 0.3 mm Hg; p = 0.02; peak gradients, 8.9 +/- 0.5 versus 11.1 +/- 0.5 mm Hg; p = 0.01). CONCLUSIONS: Three-dimensional transesophageal echocardiographic measurements of annular dynamics are valid and reliable when discrete annuloplasty devices are present. In contrast to the rigid ring, the semirigid partial band permits more physiologic geometric changes and is associated with lower postoperative mitral valve gradients.