Serum lipidomics reveals early differential effects of gastric bypass compared with banding on phospholipids and sphingolipids independent of differences in weight loss.

BACKGROUND/OBJECTIVES: Circulating phospholipids and sphingolipids are implicated in obesity-related comorbidities such as insulin resistance and cardiovascular disease. How bariatric surgery affects these important lipid markers is poorly understood. We sought to determine whether Roux-en-Y gastric bypass (RYGB), which is associated with greater metabolic improvement, differentially affects the phosphosphingolipidome compared with adjustable gastric banding (AGB). SUBJECTS/METHODS: Fasting sera were available from 59 obese women (body mass index range 37-51 kg m-2; n=37 RYGB and 22 AGB) before surgery, then at 1 (21 RYGB, 12 AGB) and 3 months follow-up (19 RYGB, 12 AGB). HPLC-MS/MS was used to quantify 131 lipids from nine structural classes. DXA measurements and laboratory parameters were also obtained. The associations between lipids and clinical measurements were studied with P-values adjusted for the false discovery rate (FDR). RESULTS: Both surgical procedures rapidly induced weight loss and improved clinical profiles, with RYGB producing better improvements in fat mass, and serum total cholesterol, low-density lipoprotein-cholesterol (LDL-C) and orosomucoid (FDR <10%). Ninety-three (of 131) lipids were altered by surgery-the majority decreasing-with 29 lipids differentially affected by RYGB during the study period. The differential effect of the surgeries remained statistically significant for 20 of these lipids after adjusting for differences in weight loss between surgery types. The RYGB signature consisted of phosphatidylcholine species not exceeding 36 carbons, and ceramides and sphingomyelins containing C22 to C25 fatty acids. RYGB also led to a sustained increase in unsaturated ceramide and sphingomyelin species. The RYGB-specific lipid changes were associated with decreases in body weight, total and LDL-C, orosomucoid and increased HOMA-S (FDR <10%). CONCLUSIONS: Concomitant with greater metabolic improvement, RYGB induced early and sustained changes in phosphatidylcholines, sphingomyelins and ceramides that were independent of greater weight loss. These data suggest that RYGB may specifically alter sphingolipid metabolism, which, in part, could explain the better metabolic outcomes of this surgical procedure.

Urgent/emergent surgical revascularization in unstable angina: influence of different type of conduits.

AIM: In patients with unstable angina (UA) undergoing nonelective myocardial revascularization we compare the outcomes of skeletonized bilateral internal mammary arteries (BIMA) vs left internal mammary artery (LIMA) and saphenous vein grafts (SVGs) vs SVGs only. METHODS: Between January 1997 and December 2003, 758 patients: 612 (80.7%) males, mean age 62+/-12 years, underwent nonelective coronary artery bypass grafting (CABG) for unstable angina; 205 (27%) were operated emergently and 553 (73%) urgently. BIMA were employed in 320 (42%) patients (Group B) , isolated LIMA and/or SVGs in 332 (44%) patients (Group M) and only SVGs in 106 (14%) (Group S). RESULTS: In-hospital mortality (B=5.9%, M=4.5% and S=7.5%), and perioperative myocardial infarction (B=2.2%; M=1.9%, S=3.7%) were similar between the 3 groups (P=NS). Actuarial survival at 1, 3 and 7 years was 98.7%, 97.5% and 96.2% in group B, 99.3%, 94.8% and 89.4% in group M (P< 0.057 at 7 years follow-up) and 98%, 93.2% and 84.3% in group S (P=0.001). At 7 years follow-up, the event-free cardiac survival (92% vs 89.1%, P=0.045), angina-free survival (98.6% vs 95.8%, P=0.056), reoperation-free cardiac survival (98% vs 96%, P= 0.05) and infarct-free cardiac survival (98.7% vs 96.9%, P=0.062) showed a consistent trend to be superior in group B. Multivariate analysis identified age >65 years (P= 0.02), left ventricular ejection fraction (LVEF) <35% (P= 0.01), >1 ischemic irreversible area (P= 0.03) as independent predictors for late deaths, while the use of the LIMA (P= 0.006) and both mammary arteries (P= 0.001) decreased the risk of late deaths. CONCLUSIONS: The use of BIMA in nonelective CABG for UA is safe and effective. There is a trend, however, toward a survival benefit with improved freedom from late cardiac events (recurrence of angina, freedom from reoperation and infarction).

Specific gut microbiota features and metabolic markers in postmenopausal women with obesity.

BACKGROUND: Gut microbial gene richness and specific bacterial species are associated with metabolic risk markers in humans, but the impact of host physiology and dietary habits on the link between the gut microbiota and metabolic markers remain unclear. The objective of this study was to identify gut metagenomic markers associated with estimates of insulin resistance, lipid metabolism and inflammation in obesity, and to explore whether the associations between metagenomic and metabolic markers persisted after adjustment for body fat, age and habitual dietary intake. METHODS: Faecal DNA from 53 women with obesity was analysed through quantitative metagenomic sequencing and analysis, and a systematic search was performed for bacterial genes associated with estimates of insulin resistance, inflammation and lipid metabolism. Subsequently, the correlations between metagenomic species and metabolic markers were tested by linear regression models, with and without covariate adjustment. RESULTS: One hundred and fourteen metagenomic species correlated with metabolic markers (P<0.001) including Akkermansia muciniphila, Bilophila wadsworthia, Bifidobacterium longum and Faecalibacterium prausnitzii, but also species not previously associated with metabolic markers including Bacteroides faecis and Dorea longicatena. The majority of the identified correlations between bacterial species and metabolic markers persisted after adjustment for differences in body fat, age and dietary macronutrient composition; however, the negative correlation with insulin resistance observed for B. longum and F. prausnitzii appeared to be modified by the intake of dietary fibre and fat, respectively. CONCLUSIONS: This study shows that several gut bacterial species are linked to metabolic risk markers in obesity, also after adjustment for potential confounders, such as long-term diet composition. The study supports the use of gut metagenomic markers for metabolic disease prediction and warrants further investigation of causality.

Axillary artery cannulation in type a aortic dissection operations.

BACKGROUND: Femoral arteries are the preferred site of peripheral cannulation for arterial inflow in type A aortic dissection operations. The presence of aortoiliac aneurysms, severe peripheral occlusive disease, atherosclerosis of the femoral vessels, and distal extension of the aortic dissection may preclude their utilization. Axillary artery cannulation may represent a valid alternative in these circumstances. METHODS: Between January 15, 1989, and August 20, 1998, in our institution, 22 of 152 operations (14.4%) for acute type A aortic dissection were performed with the use of the axillary artery for the arterial inflow. Axillary artery cannulation was undertaken in the presence of femoral arteries bilaterally compromised by dissection in 12 patients (54.5%), abdominal aorta and peripheral aneurysm in 5 patients (22.7%), severe atherosclerosis of both femoral arteries in 3 patients (13. 6%), and aortoiliac occlusive disease in 2 patients (9.1%). In all patients, distal anastomosis was performed with an open technique after deep hypothermic circulatory arrest. Retrograde cerebral perfusion was used in 9 patients (40.9%). RESULTS: Axillary artery cannulation was successful in all patients. The left axillary artery was cannulated in 20 patients (90.9%), and the right axillary artery was cannulated in 2 patients (9.1%). Axillary artery cannulation followed an attempt of femoral artery cannulation in 15 patients (68. 2%). All patients survived the operation, and no patient had a cerebrovascular accident. No axillary artery thrombosis, no brachial plexus injury, and no intraoperative malperfusion were recorded in this series. Two patients (9.1%) died in the hospital of complications not related to axillary artery cannulation. CONCLUSIONS: In patients with type A aortic dissection in whom femoral arteries are acutely or chronically diseased, axillary artery cannulation represents a safe and effective means of providing arterial inflow during cardiopulmonary bypass.

Right Y-graft, a new surgical technique using mammary arteries for total myocardial revascularization.

BACKGROUND: We report a new technique that consists of a right Y-graft using only skeletonized internal mammary arteries (IMA) for total arterial myocardial revascularization. METHODS: This technique consists of anastomosing the in situ left IMA (LIMA) and right IMA (RIMA) to the left anterior descending and obtuse marginal artery, via the transverse sinus, respectively. The distal free LIMA was anastomosed to the right coronary artery and afterwards in a Y fashion to the RIMA stem. Eleven patients with triple-vessel disease underwent coronary artery bypass grafting using this technique. Postoperatively and at follow-up all patients underwent color Doppler contrast-enhanced transthoracic echocardiography (TTE) before and after an adenosine provocation test. RESULTS: Overall, 33 IMA-coronary anastomoses were made and 11 right Y-grafts were constructed. At 1 week after operation color Doppler contrast-enhanced TTE before and after the adenosine provocation test, respectively, showed an increase in LIMA stem diameter of 0.31 mm and in mean flow 62 mL/min. Coronary flow reserve (CFR) was 2+/-0.3. The increase in RIMA stem diameter was 0.2 mm and in mean flow was 121.7 mL/min. Coronary flow reserve was 2.5+/-0.4. Only 1 patient demonstrated an anomalous Doppler pattern, suggesting a partial Y-graft closure. CONCLUSIONS: Such a technique permits total myocardial revascularization using only mammary arteries and left ventricular perfusion from both IMAs simultaneously. The color Doppler contrast-enhanced TTE is a rapid, accurate, and noninvasive test allowing a good assessment of IMA patency.

A circuit to perform a combined ultrafiltration procedure in pediatric open heart surgery.

Cardiopulmonary bypass (CPB) induces an increased capillary permeability and tissues water content due to hemodilution and the inflammatory response, resulting in organ dysfunction. The reduction of the water accumulation and inflammatory response can be achieved by employing ultrafiltration during CPB. Recently we developed a simple CPB circuit for ultrafiltration using the aortic venting tube as an inlet line. Such a technique offers the advantages of performing a combined ultrafiltration procedure and eliminating the danger of air embolism. We employed this circuit in 12 consecutive pediatric patients undergoing open heart surgery.

Lambda graft with the radial artery or free left internal mammary artery anastomosed to the right internal mammary artery: flow dynamics.

BACKGROUND: The aim of this study was to evaluate the outcome and flow dynamics of the lambda graft configuration, relative to a second arterial graft. METHODS: From 1998 to 2000, 47 patients (mean age 55.5 +/- 4.7 years) with triple-vessel disease underwent arterial revascularization using the lambda graft. The in situ left internal mammary artery (LIMA) and right internal mammary artery (RIMA) were anastomosed to the left anterior descending (LAD) and obtuse marginal arteries, respectively. In 21 patients (group I) presenting proximal or middle-third LAD or right coronary (RC) arterial stenoses, the lambda graft was constructed by anastomosing the distal LIMA, as a free LIMA graft, to the RC and proximally to the in situ RIMA. In the other 26 patients (group II) presenting with middle-distal third LAD or RC arterial stenoses, the radial artery (RA) was used to construct the lambda graft. All patients underwent transthoracic echo color Doppler before and after an adenosine test at 1 week and 3 months after operation. RESULTS: There were no hospital deaths. Overall, 47 lambda grafts were constructed. There was no difference between baseline and maximal flows and coronary flow reserve (CFR) between groups. CFR at IMA stems increased in both groups within 3 months versus 1 week [(LIMA)CFR = 2 +/- 0.3 vs 2.3 +/- 0.3 (p = 0.002) and (RIMA)CFR = 2.2 +/- 0.4 vs 2.5 +/- 0.3 (p = 0.009) in group I, and (LIMA)CFR = 2.12 +/- 0.33 vs 2.4 +/- 0.35 (p = 0.005) and (RIMA)CFR = 2.17 +/- 0.32 vs 2.52 +/- 0.26 (p = 0.001) in group II]. At 3 months versus 1 week, the (RIMA)diameter(i) (mm) at rest was 1.69 +/- 0.32 versus 1.48 +/- 0.2 (p = 0.015) in group I and 1.66 +/- 0.3 versus 1.47 + 0.2 (p = 0.01) in group II. At 6 +/- 2.4 months, all patients were free of angina. CONCLUSIONS: These data, almost identical for free LIMA and RA to RIMA using the lambda graft, demonstrate that RIMA flow reserve is adequate for multiple coronary anastomoses irrespective of the second arterial graft.

Accessory mitral valve tissue causing left ventricular outflow tract obstruction: case reports and literature review.

Accessory mitral valve (AMV) tissue is a rare congenital malformation causing left ventricular outflow tract obstruction (LVOTO). We present three patients with AMV tissue undergoing surgery. A 60-year old man presented with an AMV leaflet, mild LVOTO and coronary artery disease and underwent accessory leaflet excision and coronary revascularization. A 24-year old man presented with an AMV leaflet, LVOTO and interatrial septal defect and underwent defect closure and accessory leaflet resection. An 8-month-old girl underwent interventricular septal closure and AMV leaflet resection but died on postoperative day 5 from progressive heart failure. Another 87 cases with AMV tissue were identified in the literature The anomaly was classified as: Type I (fixed: A = nodular, B = Membranous), and type II (mobile: A = pedunculated, B = leaflet like). Type IIB was further subdivided as rudimentary chordae and developed chordae. Patients with AMV tissue causing LVOTO may undergo mass removal with acceptable postoperative outcome. Prophylactic removal of AMV tissue should not be attempted in patients with no or mild LVOTO and no other associated heart defects. These patients should be followed and observed periodically by Doppler echocardiography to identify any progression in LVOTO.

Ischemic mitral valve regurgitation grade II-III: correction in patients with impaired left ventricular function undergoing simultaneous coronary revascularization.

BACKGROUND AND AIM OF THE STUDY: Mitral valve regurgitation (MVR), occurring as a result of myocardial ischemia and global left ventricular (LV) dysfunction, is predictive of poor outcome. The study aim was to assess the feasibility of mitral valve surgery concomitant with coronary artery bypass grafting (CABG) in patients with ischemic MVR grade II-III and impaired LV function. METHODS: Between January 1996 and July 2000, 99 patients with grade II and III ischemic MVR and LV ejection fraction (LVEF) 17-30% underwent either combined mitral valve surgery and CABG (group I, n = 49) or isolated CABG (group II, n = 50). LVEF (%), LV end-diastolic diameter (LVEDD; mm), LV end-diastolic pressure (LVEDP; mmHg), LV end-systolic diameter (LVESD; mm) respectively were 27.5+/-5, 67.7+/-7, 27.7+/-4 and 51.4+/-7 in group I versus 27.8+/-4, 67.5+/-6, 27.5+/-5 and 51.2+/-6 in group II. In group I, mitral valve repair was performed in 43 patients (88%) and replacement in six (12%). RESULTS: Preoperative data analysis showed no difference between groups. Five patients (10%) died in group I, compared with six (12%) in group II (p = NS). Within six months of surgery, LV function and geometry improved significantly in group I versus group II (LVEF, p <0.001; LVEDD, p = 0.002; LVESD, p = 0.003, LVEDP, p <0.001); only mild improvements were seen in group II. The regurgitation fraction decreased significantly in group I patients after surgery (p <0.001). Cardiac index increased significantly in groups I and II (p <0.001 and p = 0.03, respectively). In group I at follow up, four of six patients undergoing mitral valve replacement died, compared with five of 43 patients (11.5%) undergoing mitral valve repair (p = 0.007). At three years, the overall survival in group II was significantly lower than in group I (p <0.009). CONCLUSION: Both MV repair and replacement preserving subvalvular apparatus in patients with impaired LV function offered acceptable outcome in terms of morbidity and survival. Surgical correction of grade II-III MVR in patients with impaired LV function should be taken into consideration as it provides better survival and improves LV function.

Undergoing cardiopulmonary bypass using enoxaparin only during a cardiac transplantation procedure.

The use of enoxaparin as a replacement drug to standard heparin, for anticoagulation during extracorporeal circulation, in patients with heparin-induced thrombocytopenia, is still very limited. Enoxaparin significantly reduces thrombin formation and activity during cardiopulmonary bypass. The prolonged circulating rate, slow elimination rate and non-total reversion of enoxaparin by protamine can induce important postoperative bleeding. We are describing the first case of cardiac transplantation where enoxaparin was used as a replacement drug to standard heparin.

Urgent surgical revascularization of unstable angina. Influence of double mammary arteries.

OBJECTIVE: Aim of this study was to evaluate retrospectively: (1) the outcome in patients with unstable angina (UA) refractory to the medical therapy undergoing urgent-emergent CABG; (2) the influence of both IMAs employment. PATIENTS AND METHODS: Between January 1995 and July 2000, 576 (28.5%) consecutive patients with UA underwent CABG procedure. 182 (31.6%, Group I) patients, presenting unstable hemodynamic or angina pectoris refractory to the maximal medical therapy, underwent urgent/emergent CABG. 397 (68.4%, Group II) patients, after the maximal medical therapy did not present angina's episodes or ECG alterations and underwent elective CABG procedure. Preoperative data were similar in the two groups. Both IMAs were used in 68 (37.4%) patients of I and 152 (38%) of II (P>0.05) to left side revascularization. RESULTS: CAD extension was greater in Group I: 45 (24.7%) patients presented ischemia in >1 area vs 53 (13.5%) in II (P<0.001). Incidence of anteroseptal ischemia resulted significantly higher in I (P=0.017); left main coronary artery stenosis was present in 68 (37%) patients in I vs 108 (27%) in II (P=0.01). LV function resulted significantly depressed in I, demonstrated by a significantly lower LVEF (P<0.001), higher NYHA class (P<0.001) and preoperative incidence of IABP (P<0.001). Intraoperative data analysis did not reveal any difference between groups. Hospital mortality was 13 (7%) and 21 (5.3%) patients in I and II respectively (P=ns). Multivariate analysis of all preoperative and intraoperative variables revealed the age >65 years (P=0.01), congestive heart failure (P<0.001), LVEF<35% (P=0.03), >1 ischemic area (P=0.02) as strong predictors for poor overall survival, and LIMA (P=0.006) and both IMAs (P=0.001) as strong predictors for good overall survival. Actuarial survival at 1, 3 and 5 years resulted to be 98.5, 96.5 and 90% in I and 99, 96 and 92% in II (P=ns). CONCLUSION: CABG has been associated with acceptable outcome in patients with UA which should be applied soonest possible in patients refractory to medical treatment. Total coronary revascularization and employment of both IMAs for left myocardial side are associated with low operative risk and incidence of complications, permit to have acceptable short and long-term outcome in this pool of patients.

Respiratory dysfunction after coronary artery bypass grafting employing bilateral internal mammary arteries: the influence of intact pleura.

OBJECTIVE: To evaluate the role of intact pleurae regarding the postoperative respiratory functional status in patients undergoing coronary revascularization employing both internal mammary arteries (IMAs), according to the pedunculated or skeletonized technique (SKT) with opened or intact pleurae. MATERIALS AND METHODS: Using both IMAs, 299 patients underwent elective coronary revascularization. They were randomized and divided into group I (n=82, undergoing IMA harvesting according to the SKT without opening the pleurae); group II (n=186, undergoing IMA harvesting according the pedunculated technique with open pleurae); and group III (n=31, undergoing IMA harvesting according the SKT with incidentally opened pleurae). There were no differences regarding the preoperative patient characteristics and the anaesthetic and surgical management. RESULTS: There were two deaths in group I versus seven in group II and one in group III (P=ns). The number of total arterial myocardial revascularization and arterial composite grafts was significantly higher in groups I and III than in group II, (P<0.001 and P<0.005, respectively). The incidence of postoperative complications was similar between groups. Blood loss of >1000 ml was significantly higher in group II than group I (P<0.028); but the incidence of re-thoracotomy and blood transfusion was similar between groups. The mechanical ventilation time was significantly higher in groups II and III versus group I (P<0.018 and P<0.02, respectively). The incidence of prolonged ventilation (>24 h), pleural effusion, thoracocentesis and atelectasis, resulted in being significantly higher in group II than group I. The incidence of thoracocentesis was significantly higher in group III than group I. The pain score and analgesic requirements at 1-12 h after awakening were significantly higher in groups II and III versus group I, becoming similar after the chest tubes were removed. PaO(2) was significantly higher, and PaCO(2) and FiO(2) were significantly lower in group I than groups II and III at 1 and 4 h before extubation and at 1 and 4 h after extubation. PaO(2) and PaCO(2) became similar between groups at the 5th postoperative day. CONCLUSIONS: According to our results, we may conclude that pleural integrity has beneficial effects on the respiratory functional status after coronary revascularization using both IMAs. A meticulous and more careful IMA harvesting approach significantly reduces the postoperative morbidity regarding the pulmonary functional status, and as a consequence, reduces the hospital costs.

Accessory mitral valve leaflet in an adult with coronary artery disease.

Accessory mitral valve leaflet is a very rare cause of left ventricular outflow tract obstruction. We report a patient presenting this cardiac abnormality who undergone cardiac surgery. A 60-year-old man, presented coronary artery disease and moderate left ventricular tract obstruction due to accessory mitral valve leaflet. The accessory mitral valve leaflet had the typical morphology of a parachute-shaped attached partially to the anterior mitral valve leaflet, with chordae tendinae attached to: 1) an accessory papillary muscle inserted at the free-wall closed to the apex; 2) interconnected with the chordae tendinae of the anterior mitral valve leaflet; 3) a second accessory papillary muscle inserted to the interventricular septum. He underwent successful coronary revascularization of 2 vessels and accessory leaflet excision. A review of 21 cases with accessory mitral valve leaflet is reported.

Emergency management of spontaneous coronary artery dissection.

Six cases of spontaneous coronary arteries dissection are reported. In one patient, triple vessel spontaneous coronary artery dissection was identified. Another patient presented spontaneous left main coronary artery dissection. In one case we found the spontaneous dissection of the left anterior descending artery associated with distal aortic arch dissection. These conditions are very rare and may present a surgical dilemma. Causative factors and underlying pathology are clarified. Prompt diagnosis and surgical intervention is safe and effective. Early recognition of left main coronary artery dissection or three-vessel dissection is essential because urgent coronary artery bypass grafting may be life saving.

Antiphospholipid antibodies and intracardiac thrombosis. A case report.

The antiphospholipid syndrome (APS) has been associated with multiple cardiac abnormalities. The present report describes a case of right ventricle thrombus in a 51-year-old woman with a history of autoimmune haemolytic anemia and antiphospholipid antibodies. Transthoracic echocardiography demonstrated the presence of a right ventricle mass, mimicking a myxoma. She underwent open heart removal of the mass and was started on indefinitely anticoagulant therapy. At 2 years follow-up she was free of symptoms.

Chylothorax: a complication after internal thoracic artery harvesting.

Chylothorax is a rare but serious complication of cardiac surgery. A 64-year-old man with three-vessel disease underwent coronary artery bypass grafting. Ten days later he developed left pleural effusion. An intercostal drain was inserted and 1600 ml of pale pink, milky fluid were obtained. The results of biochemical analysis were consistent with chyle. The diagnosis of a left chylothorax was made. Conservative treatment consisting of total parenteral nutrition and pleural drainage was successfully employed. In the literature we found 17 cases in which the development of chylothorax after a coronary revascularization procedure is described.

Macrophage gene expression in adipose tissue is associated with insulin sensitivity and serum lipid levels independent of obesity.

OBJECTIVE: Obesity is linked to both increased metabolic disturbances and increased adipose tissue macrophage infiltration. However, whether macrophage infiltration directly influences human metabolism is unclear. The aim of this study was to investigate if there are obesity-independent links between adipose tissue macrophages and metabolic disturbances. DESIGN AND METHODS: Expression of macrophage markers in adipose tissue was analyzed by DNA microarrays in the SOS Sib Pair study and in patients with type 2 diabetes and a BMI-matched healthy control group. RESULTS: The expression of macrophage markers in adipose tissue was increased in obesity and associated with several metabolic and anthropometric measurements. After adjustment for BMI, the expression remained associated with insulin sensitivity, serum levels of insulin, C-peptide, high density lipoprotein cholesterol (HDL-cholesterol) and triglycerides. In addition, the expression of most macrophage markers was significantly increased in patients with type 2 diabetes compared to the control group. CONCLUSION: Our study shows that infiltration of macrophages in human adipose tissue, estimated by the expression of macrophage markers, is increased in subjects with obesity and diabetes and associated with insulin sensitivity and serum lipid levels independent of BMI. This indicates that adipose tissue macrophages may contribute to the development of insulin resistance and dyslipidemia.