Cytoprotective and Antioxidant Effects of Steen Solution on Human Lung Spheroids and Human Endothelial Cells

Respiratory diseases represent a major healthcare burden worldwide. Lung transplantation (LTx) is the "gold standard" for end-stage patients, strongly limited by shortage of available/suitable donor lungs. Normothermic ex vivo lung perfusion (EVLP) has significantly increased the number of lungs suitable for transplantation. Steen solution is used for EVLP, but the mechanisms involved in its beneficial properties remain to be clarified. We investigated the effects of Steen solution in an in vitro protocol of cold starvation and normothermic recovery on human lung spheroids, named pneumospheres (PSs), containing epithelial/basal cells, and on endothelial human umbilical vein endothelial cells (HUVEC). Steen solution significantly preserved the viability of PSs, reduced reactive oxygen species (ROS) release by PSs and HUVECs, decreased NADPH-oxidase (NOX) activity in PSs, and reduced inflammatory cytokines expression levels in HUVECs. Steen solution was able to specifically reduce NADPH oxidase 2 (NOX2) isoform activation, particularly in PSs, as detected by soluble-NOX2 peptide and p47-phosphorylation. Interestingly, a specific NOX2 inhibitor could partly mimic the pro-survival effect of Steen on PSs. We provide the first evidence that Steen solution can preserve lung epithelial/progenitor cells viability partially through NOX2 downregulation, and exert antioxidant effects on parenchymal cells, with consequent ROS reduction. These results suggest that NOX2 inhibition might be an additional strategy to reduce cellular damage during LTx procedures.

Heart rate reduction with esmolol is associated with improved arterial elastance in patients with septic shock: a prospective observational study

PURPOSE

Ventricular-arterial (V-A) decoupling decreases myocardial efficiency and is exacerbated by tachycardia that increases static arterial elastance (Ea). We thus investigated the effects of heart rate (HR) reduction on Ea in septic shock patients using the beta-blocker esmolol. We hypothesized that esmolol improves Ea by positively affecting the tone of arterial vessels and their responsiveness to HR-related changes in stroke volume (SV).

METHODS

After at least 24 h of hemodynamic optimization, 45 septic shock patients, with an HR ≥95 bpm and requiring norepinephrine to maintain mean arterial pressure (MAP) ≥65 mmHg, received a titrated esmolol infusion to maintain HR between 80 and 94 bpm. Ea was calculated as MAP/SV. All measurements, including data from right heart catheterization, echocardiography, arterial waveform analysis, and norepinephrine requirements, were obtained at baseline and at 4 h after commencing esmolol.

RESULTS

Esmolol reduced HR in all patients and this was associated with a decrease in Ea (2.19 ± 0.77 vs. 1.72 ± 0.52 mmHg l(-1)), arterial dP/dt max (1.08 ± 0.32 vs. 0.89 ± 0.29 mmHg ms(-1)), and a parallel increase in SV (48 ± 14 vs. 59 ± 18 ml), all p < 0.05. Cardiac output and ejection fraction remained unchanged, whereas norepinephrine requirements were reduced (0.7 ± 0.7 to 0.58 ± 0.5 µg kg(-1) min(-1), p < 0.05).

CONCLUSIONS

HR reduction with esmolol effectively improved Ea while allowing adequate systemic perfusion in patients with severe septic shock who remained tachycardic despite standard volume resuscitation. As Ea is a major determinant of V-A coupling, its reduction may contribute to improving cardiovascular efficiency in septic shock.

C2238/αANP modulates apolipoprotein E through Egr-1/miR199a in vascular smooth muscle cells in vitro

Subjects carrying the T2238C ANP gene variant have a higher risk to suffer a stroke or myocardial infarction. The mechanisms through which T2238C/αANP exerts detrimental vascular effects need to be fully clarified. In the present work we aimed at exploring the impact of C2238/αANP (mutant form) on atherosclerosis-related pathways. As a first step, an atherosclerosis gene expression macroarray analysis was performed in vascular smooth muscle cells (VSMCs) exposed to either T2238/αANP (wild type) or C2238/αANP. The major finding was that apolipoprotein E (ApoE) gene expression was significantly downregulated by C2238/αANP and it was upregulated by T2238/αANP. We subsequently found that C2238/αANP induces ApoE downregulation through type C natriuretic peptide receptor (NPR-C)-dependent mechanisms involving the upregulation of miR199a-3p and miR199a-5p and the downregulation of DNAJA4. In fact, NPR-C knockdown rescued ApoE level. Upregulation of miR199a by NPR-C was mediated by a reactive oxygen species-dependent increase of the early growth response protein-1 (Egr-1) transcription factor. In fact, Egr-1 knockdown abolished the impact of C2238/αANP on ApoE and miR199a. Of note, downregulation of ApoE by C2238/αANP was associated with a significant increase in inflammation, apoptosis and necrosis that was completely rescued by the exogenous administration of recombinant ApoE. In conclusion, our study dissected a novel mechanism of vascular damage exerted by C2238/αANP that is mediated by ApoE downregulation. We provide the first demonstration that C2238/αANP downregulates ApoE in VSMCs through NPR-C-dependent activation of Egr-1 and the consequent upregulation of miR199a. Restoring ApoE levels could represent a potential therapeutic strategy to counteract the harmful effects of C2238/αANP.

Autologous pericardium annuloplasty: a "physiological" mitral valve repair

AIM

Autologous pericardium annuloplasty (APA) is an alternative to prosthetic ring implantation for mitral valve (MV) repair, avoiding the use of foreign material and preserving the mitral annulus' physiological motion. However, data on durability are questionable. Therefore, we analyzed long-term outcomes of treating degenerative mitral regurgitation (MR) with APA.

METHODS

Four hundred ninety patients (mean age, 54.3±11.3 years, [15-77 years]; N.=360 men [74.1%]) who had undergone APA and neochordae implantation between July 1988 and December 2006 were retrospectively studied.

RESULTS

MR was purely degenerative in 434 (89.3%) patients; endocarditis was present in 44 (9.1%) patients; an anterior, posterior, or bileaflet prolapse was present in 32 (6.6%), 241 (49.6%), and 213 (43.8%) patients, respectively. Clinical follow-up was 100% complete at a median of 6.5 years (5th percentile, 0.9; 95th percentile, 14.9) with an echocardiographic study in 92% of patients. In-hospital mortality was 1% (5 deaths); overall and late cardiac mortality were 7.6% and 3.9% (37 and 19 deaths), respectively. Kaplan-Meier curves for overall survival, late cardiac survival, and freedom from reoperation at 15 years (20 cases) were 86% (95%CI 80-91), 93% (95%CI 88-96), and 93% (95%CI 88-96), respectively. At 15 years, freedom from recurrent MR (28 patients) and endocarditis (6 events) were 86% (95%CI 76-91) and 97% (95%CI 92-99). Dehiscence, significant calcification of APA, and hemolysis never occurred. At reoperations, annular pericardium appeared covered by a smooth layer of tissue.

CONCLUSION

APA is feasible, safe, and cost-effective, providing long-term durability, high survival, and a low rate of valve-related complications.

Renal Stenting for Kidney Salvage in the Management of Renal Artery Atherosclerotic Stenosis

We studied the usefulness of preoperative resistance index to select patients who will benefit most from renal stenting. Sixty-two patients underwent renal stenting. All had chronic renal insufficiency with serum creatinine values ranging from 1.5 to 2.5 mg/dL and blood urea nitrogen between 80 and 107 mg/dL. All treated renal artery stenosis were >70%. Reduction in blood pressure in the early stages was observed in 39 (62.9%) patients; 31 (79.4%) patients returned to preoperative values within 12 months. A progressive reduction in creatinine values and blood urea nitrogen was reached in 43 (69.4%) patients, 12 (19.4%) patients remained unchanged, and the remaining 7 (11.2%) patients worsened. The best improvement in renal function was obtained in patients with a resistance index of ≤0.75 A preoperative resistance index up to 0.75 could be used as an indicator to predict which candidates will have improved renal function after stenting.

An updated systematic review and meta-analysis on impedance threshold devices in patients undergoing cardiopulmonary resuscitation

INTRODUCTION

Uncertainty persists on the clinical impact of impedance threshold devices in out-of-hospital cardiac arrest. We conducted an updated systematic review on impedance threshold devices.

METHODS

Several databases were searched for studies testing the effectiveness of impedance threshold devices in patients with cardiac arrest. The primary endpoint was long-term survival.

RESULTS

Seven trials (11,254 patients) were included. In 4 studies (2,284 patients) impedance threshold devices were used with active compression-decompression-cardiopulmonary resuscitation, and in the others alone. Overall, impedance threshold devices did not impact on the rate of return of spontaneous circulation (odds ratio=1.17 [0.96-1.43], p=0.114), favorable neurologic outcome (odds ratio=1.56 [0.97-2.50], p=0.065), or long-term survival (odds ratio=1.22 [0.94-1.58], p=0.127). These analyses were fraught with heterogeneity (respectively, p=0.055, p=0.236, and p=0.011) and inconsistency (respectively, I-squared=51% , I-squared=27% , and I-squared=67%). Exploratory analysis showed that combined use of impedance threshold devices with active compression-decompression significantly increased the likelihood of return of spontaneous circulation (odds ratio=1.19 [1.00-1.40], p=0.045), favorable neurologic outcome (odds ratio=1.60 [1.14-2.25], p=0.006), and long-term survival (odds ratio=1.52 [1.11-2.08], p=0.009). The favorable impact of the interaction between impedance threshold devices and active compression-decompression was also confirmed at meta-regression analysis (respectively, b=0.195 [0.004-0.387], p=0.045, b=0.500 [0.079-0.841], p=0.018, b=0.413 [0.063-0.764], p=0.021).

CONCLUSIONS

The evidence base on impedance threshold devices is apparently inconclusive, with a neutral impact on clinically relevant outcomes. However, exploratory analysis focusing on the combined use of impedance threshold devices with active compression-decompression suggests that this combo treatment may be useful to improve patient prognosis.

Network meta-analysis on the comparative effectiveness and safety of transcatheter aortic valve implantation with CoreValve or Sapien devices versus surgical replacement

INTRODUCTION

Surgical replacement for aortic stenosis is fraught with complications in high-risk patients. Transcatheter techniques may offer a minimally invasive solution, but their comparative effectiveness and safety is uncertain. We performed a network meta-analysis on this topic.

METHODS

Randomized trials on transcatheter aortic valve replacement vs surgery were searched. The primary outcome was all cause death. Risk estimates were obtained with Bayesian network meta-analytic methods.

RESULTS

Four trials with 1,805 patients were included. After a median of 8 months, risk of death and myocardial infarction was not different when comparing surgery versus transcatheter procedures, irrespective of device or access. Conversely, surgery was associated with higher rates of major bleeding (odds ratio vs CoreValve=3.03 [95% credible interval: 2.23-4.17]; odds ratio vs transfemoral Sapien =1.82 [1.21-2.70]; odds ratio vs transapical Sapien =2.08 [1.20-3.70]), and acute kidney injury (odds ratio vs CoreValve =2.08 [1.33-3.32]; odds ratio vs transapical Sapien =2.78 [2.21-99.80]), but lower rates of pacemaker implantation (odds ratio vs CoreValve =0.41 [0.28-0.59]), and moderate or severe aortic regurgitation (odds ratio vs CoreValve =0.06 [0.02-0.27]; odds ratio vs Sapien=0.17 [0.02-0.76]). Strokes were less frequent with CoreValve than with transfemoral Sapien (odds ratio =0.32 [0.13-0.73]) or transapical Sapien (odds ratio =0.33 [0.10-0.93]), whereas pacemaker implantation was more common with CoreValve (odds ratio vs surgery =2.46 [1.69-3.61]; odds ratio vs transfemoral Sapien =2.22 [1.27-3.85]).

CONCLUSIONS

Survival after transcatheter or surgical aortic valve replacement is similar, but there might be differences in the individual safety and effectiveness profile between the treatment strategies and the individual devices used in transcatheter aortic valve implantation.

Lung transplantation for cystic fibrosis: outcome of 101 single-center consecutive patients

Bilateral sequential lung transplantation (BSLT) is nowadays considered a valid therapeutic option for patients with end stage cystic fibrosis. We report our experience with 104 BSLTs in 101 patients. The overall survivals at 1, 3, 5, 10 years were 79%, 65%, 58%, and 42%, respectively. Perioperative mortality was 14.8% (n = 15). The leading causes of perioperative mortality were primary graft dysfunction and sepsis. Three patients were retransplanted owing to obliterative bronchiolitis. In 70 cases (69%), patients displayed ≥ 1 additional risk factors: previous lung resections, colonization by Burkholderia cepacia, diabetes, pneumothorax, or noninvasive ventilatory support. The mean preoperative 1-second forced expiratory volume of 0.69 ± 0.2 L (22%) increased to 85% at 1 year after the operation. The mean time on the waiting list was 12 ± 5 months. The 5 patients treated with extracorporeal membrane oxygenation before urgent transplantation were operated after 3, 5, 6, 30, and 3 days respectively. During the procedure, cardiopulmonary bypass was required in 33 patients (32%). Lung transplantation represents a unique opportunity to ameliorate the quality and improve the survival of patients affected by cystic fibrosis. Timing of referral and patient selection remain crucial for success.

Comparative effectiveness of novel oral anticoagulants for atrial fibrillation: evidence from pair-wise and warfarin-controlled network meta-analyses

INTRODUCTION

Novel oral anticoagulants have been tested against warfarin for atrial fibrillation, yet no direct comparison is available. We thus aimed to perform pair-wise (direct) and warfarin-adjusted network (i.e. indirect) meta-analyses of novel oral anticoagulants for atrial fibrillation.

METHODS

Databases were searched for randomized warfarin-controlled trials of novel anticoagulants for non-valvular atrial fibrillation. The primary end-point was long-term stroke/systemic embolism. Odds ratios (95% intervals) were computed with RevMan and WinBUGS.

RESULTS

Seven trials (52701 patients) were included, focusing on apixaban, dabigatran, edoxaban and rivaroxaban. Pair-wise meta-analysis showed that after a weighted average of 23 months these novel anticoagulants lead to significant reductions in the risk of stroke/systemic embolism (odds ratio=0.81 [0.71-0.92], I2=23%) and all cause death (odds ratio=0.88 [0.82-0.95], I2=0%) in comparison to warfarin. Network meta-analysis showed that apixaban and dabigatran proved similarly superior to warfarin in preventing stroke/systemic embolism (odds ratio=0.78 [0.62-0.96] for apixaban vs warfarin; odds ratio=0.66 [0.52-0.84] for high-dose dabigatran vs warfarin; odds ratio for apixaban vs high-dose dabigatran=1.17 [0.85-1.63]), but apixaban was associated with fewer major bleedings (odds ratio=0.73 [0.57-0.93]) and drug discontinuations (odds ratio=0.64 [0.52-0.78]) than dabigatran. Rivaroxaban did not reduce stroke/systemic embolism (odds ratio=0.87 [0.71-1.07]) or major bleedings in comparison to warfarin (odds ratio=0.87 [0.71-1.07]) and was associated with more major bleedings in comparison to apixaban (odds ratio=1.52 [1.19-1.92]). Data for edoxaban were inconclusive.

CONCLUSIONS

Novel oral anticoagulants appear as a very promising treatment option for atrial fibrillation.

Neoplastic superior vena cava obstruction: combined approach

Primary adult cardiac tumors are rare entities with a low indices. In 90% of cases are benign. Among malignant tumors angiosarcomas are the most common. In 80% of cases they arises in the right atrium, more often in younger males as compared to benign tumors. The majority of them manifests as locally already advanced disease, precluding macroscopically complete surgical resection. Moreover, the presence of macro- and micrometastasis makes the prognosis always prohibitive. The duration of symptoms is in the order of months and the median survival ranges from 6 to 11 months. Death cause is usually a complication of locally recurrent disease: tamponade, hemopericardium are common. Treatment is multidisciplinary. The combination of chemo- and radiotherapy with surgery aims to increase survival. In the management of unresectable tumors, due to anatomic reason or Iocoregional spread, an important role is played by pre-operatory chemotherapy or chemo-radiation to increase short term survival.

Thrombin and thrombin-derived peptides promote proliferation of cardiac progenitor cells in the form of cardiospheres without affecting their differentiation potential

Many studies demonstrated that human adult cardiac progenitor cells in the form of cardiospheres (CSps) could represent a powerful candidate for cardiac cell therapy. To achieve the clinical translation of this biotechnological product, the development of well-defined culture conditions is required to optimize their proliferation and differentiation. Thrombin, a serine protease acting through the protease-activated receptor 1 (PAR-1) signalling to modulate many cellular functions such as proliferation and differentiation in several cell types, is one of the factors included in the CSps medium. Therefore, the assessment of the effective dependence of the thrombin related cellular effects from PAR-signalling is strategic both for understanding the biological potential of these cells and for the GMP translation of the medium formulation, using synthesised analogs. In this study the effects of thrombin on human CSps and their potential relationship with the specific proteolytic activation of PAR-1 have been investigated in different culture conditions, including thrombin inhibitor hirudin and PAR-1 agonist/ antagonist peptides TFLLR and MUMB2. In this study we show that, in the presence of thrombin and TFLLR, CSps, in which PAR-1 expression was evidenced by immunofluorescence and western blot analysis, increase their proliferation activity (BrdU assay). Such increased proliferative rate was consistently associated with a higher phosphorylation level of the cell cycle inhibitor GSK3. Concerning the assessment of the potential effects of thrombin and its agonist on differentiation, both western blot and real-time PCR analysis for stemness, cardiac and vascular markers (such as cKit, cx43 and KDR) showed that CSps commitment was substantially unaffected, except for GATA4 mRNA, whose transcription was down-regulated in the presence of the natural protease, but not after treatment with TFLLR. In conclusion, activation of PAR-1-dependent signalling is important to support CSps proliferative potential, keeping unaltered or at best stable their differentiation properties. The availability of thrombin agonists, such as TFLLR, able to guarantee the required growth effect without affecting CSps lineage commitment, could represent a technological improvement for cost-effective, easy-to-handle and GMPtranslatable synthetic media.

New perspectives to repair a broken heart

The aim of cardiac cell therapy is to restore at least in part the functionality of the diseased or injured myocardium by the use of stem/progenitor cells. Recent clinical trials have shown the safety of cardiac cell therapy and encouraging efficacy results. A surprisingly wide range of non-myogenic cell types improves ventricular function, suggesting that benefits may result in part from mechanisms that are distinct from true myocardial regeneration. While clinical trials explore cells derived from skeletal muscle and bone marrow, basic researchers are investigating sources of new cardiomyogenic cells, such as resident myocardial progenitors and embryonic stem cells. In this commentary we briefly review the evolution of cell-based cardiac repair, some progress that has been made toward this goal, and future perspectives in the regeneration of cardiac tissue.

Carnitine inhibits arachidonic acid turnover, platelet function, and oxidative stress

Carnitine is a physiological cellular constituent that favors intracellular fatty acid transport, whose role on platelet function and O(2) free radicals has not been fully investigated. The aim of this study was to seek whether carnitine interferes with arachidonic acid metabolism and platelet function. Carnitine (10-50 microM) was able to dose dependently inhibit arachidonic acid incorporation into platelet phospholipids and agonist-induced arachidonic acid release. Incubation of platelets with carnitine dose dependently inhibited collagen-induced platelet aggregation, thromboxane A(2) formation, and Ca(2+) mobilization, without affecting phospholipase A(2) activation. Furthermore, carnitine inhibited platelet superoxide anion (O(2)(-)) formation elicited by arachidonic acid and collagen. To explore the underlying mechanism, arachidonic acid-stimulated platelets were incubated with NADPH. This study showed an enhanced platelet O(2)(-) formation, suggesting a role for NADPH oxidase in arachidonic acid-mediated platelet O(2)(-) production. Incubation of platelets with carnitine significantly reduced arachidonic acid-mediated NADPH oxidase activation. Moreover, the activation of protein kinase C was inhibited by 50 microM carnitine. This study shows that carnitine inhibits arachidonic acid accumulation into platelet phospholipids and in turn platelet function and arachidonic acid release elicited by platelet agonists.

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.

Surgical treatment of abdominal aortic aneurysms associated with aortic valve incompetence: strategies and outcomes

BACKGROUND

The exact incidence of associated aortic valve incompetence (AVI) and abdominal aortic aneurysm (AAA) in the general population is not known. In recent years, we have observed this association with increasing frequency. This observation is probably due to the extensive preoperative screening of the cardiac and vascular status of patients who are candidates for surgical procedures. The choice of the optimal surgical strategy is needed to achieve low operative morbidity and mortality. The present study reviews our experience with a subset of patients suffering the association of AVI and large AAA. Surgical strategy, clinical management and outcome are presented.

METHODS

Between January 1982 and May 2000, 76 patients with the association of AAA and AVI have been evaluated in our institution. Forty-four patients have been treated for both AAA and aortic valve (AV) regurgitation. These patients have been divided into three groups on the basis of the surgical strategy adopted. Group 1: combined procedure (16 patients); group 2: AAA repair prior to AV surgery (nine patients); group 3: AV surgery prior to aneurysm repair (19 patients).

RESULTS

Hospital mortality was 4.5% (two patients); overall mortality was 6.8% (three patients).

CONCLUSIONS

In patients with AAA and AVI, an accurate and complete preoperative evaluation is essential. Surgical strategy should be individualized on the basis of the cardiac preoperative status.

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.

Concomitant carotid endarterectomy and coronary bypass surgery: should cardiopulmonary bypass be used for the carotid procedure?

BACKGROUND AND OBJECTIVES

With the increasing age of patients undergoing coronary artery bypass grafting (CABG), a greater number have associated clinically significant carotid disease. This study determined the morbidity and mortality for combined carotid endarterectomy (CEA)/CABG using cardiopulmonary bypass (CPB) for both procedures versus a combined approach using CPB only during CABG.

PATIENTS AND METHODS

Between 1993 and 2000, 65 patients (Group I) underwent combined CEA and CABG using CPB for both surgical procedures and 88 patients (Group II) underwent combined CEA and CABG using CPB only during CABG. The demographic, clinical, and carotid and coronary angiographic data were similar between groups. In Group I, 22 (33.8%) patients and 32 (36%) patients in Group II presented with contralateral carotid artery stenosis.

RESULTS

CPB time was significantly longer in Group I, 127+/-21 minutes versus 98+/-11 minutes in Group II patients (p = 0.001). The incidence of surgical revision for bleeding and deep sternal wound infection was higher in Group I patients, 2 (3%) versus 1 (1.1%) and 5 (7.7%) versus 2 (2.2%), respectively, but not significant. Hospital mortality in Group I was 6% (4 patients) versus 5.7% (5 patients) in Group II (p = ns). Neurologic complications occurred in 4 (6%) and 5 (5.7%) patients in Group I and II, respectively (p = ns). Postoperative renal dysfunction was more common in Group I patients (22 [33.8%]) then in Group II patients 16 (19%) (p = 0.04). Of these patients, (16 [19%]) 8 (12.3%) in Group I and 6 (6.8%) in Group II required postoperative ultrafiltration (p = ns). Infectious complications were more frequent in Group I patients, 5 (7.7%) versus 2 (2.3%), but not statistically significant (p = ns). Overall actuarial survival at 1, 3, and 5 years, including all deaths, was 92%, 88%, and 82% in Group I versus 93%, 86%, and 81% in Group II (p = ns). Overall freedom from stroke at 5 years was 87.5% in Group I and 86.4% in Group II.

CONCLUSIONS

We conclude that combined CEA/CABG using CPB only during the myocardial revascularization procedure remains the technique of choice in patients with coronary and carotid artery disease, offering better outcome in terms of perioperative morbidity than a combined CEA/CABG using CPB for both procedures.

Perioperative use of tirofiban hydrochloride (Aggrastat) does not increase surgical bleeding after emergency or urgent coronary artery bypass grafting

BACKGROUND

The platelet glycoprotein IIb/IIIa inhibitor tirofiban hydrochloride improves outcome in patients with acute coronary syndrome. Nevertheless, a considerable number of patients require emergency or urgent coronary artery bypass grafting and may be at increased risk of postoperative bleeding after treatment with this molecule. The aim of this study is to evaluate the incidence of bleeding complications among patients undergoing bypass grafting after treatment with tirofiban.

METHODS

We investigated the influence of the molecule on postoperative bleeding after cardiac surgery, comparing 2 groups of patients undergoing emergency or urgent coronary artery bypass grafting: group A (n = 20) received tirofiban, and group B (n = 68) received conventional therapy with intravenous heparin up until the operation. A total of 88 patients underwent coronary artery bypass surgery within 2 hours of ceasing the hemodynamic study. Clinical outcome, chest tube outputs, bleeding complications, transfusion requirements, platelet and hemoglobin counts, and clinical complications were examined.

RESULTS

Bleeding differences were noted between the 2 groups at 8, 16, and 24 hours postoperatively. The incidence of blood, platelet, and fresh frozen plasma transfusions was higher in the control group. Postoperative thrombocytopenia was preserved in group A (199.5 +/- 70.4 vs 150.6 +/- 33.4 10(3)/mL, P <.01). No significant differences were noted between the 2 groups in the incidence of perioperative myocardial infarction, but significant differences were noted in enzyme levels, length of stay in the intensive care unit, and length of stay in the hospital. No deaths were observed. Hospital morbidity was increased in group B because of factors that were not apparently linked with tirofiban infusion.

CONCLUSIONS

Patients may safely undergo coronary artery bypass surgery after treatment with tirofiban hydrochloride. This molecule, administered in the immediate preoperative period, has no adverse clinical effects and does not seem to negatively influence the incidence of perioperative myocardial infarction. Although extracorporeal circulation can modify platelet numbers and function, our ongoing data could show significant reduction in the loss of platelets induced by cardiopulmonary bypass, minor postoperative bleeding, and a minor transfusion requirement in general.

Restoration of patency after apparent occlusion of the lambda-graft's right branch

The "string sign" is a physiological and reversible response of the internal mammary artery (IMA) anastomosed to a moderately stenotic coronary artery. We describe a patient who presented postoperatively with a string sign phenomenon of the right branch of the lambda-composite graft. The graft regained full patency 32 months after the surgical procedure with progression of the native coronary artery stenotic lesion. This case demonstrates that under specific conditions, such as the progression of native coronary artery disease, a no-flow composite graft employing IMAs can only regain patency and functional status in the same way as in situ IMAs. These findings confirm that the IMA remains the conduit of choice not only for its long-term patency, but also for its physiological adaptation characteristics.

Beating heart myocardial revascularization on extracorporeal circulation in patients with end-stage coronary artery disease

OBJECTIVES

To evaluate in a cohort of ESCAD patients (pts) the effects of on-pump/beating-heart versus conventional CABG in terms of early and mid-term survival and morbidity and LV function improvement.

METHODS

Between January 1993 and December 2000, 78 (Group I) ESCAD pts underwent on-pump/beating-heart surgery. Mean age in Group I was 66.2+/-6 (58-79), NYHA and CCS class were 3.2+/-0.6 and 3.3+/-0.4 respectively, Myocardial viability index 0.69+/-0.1 (%), LVEF (%) 24.8+/-4, LVEDP (mmHg) 28.1+/-5.8 and LVEDD(mm) 69.5+/-6. Group II consisted in 78 ESCAD patients undergoing conventional CABG selected in a randomized fashion from an age, sex, and LVEF corrected group of patients. Mean age in Group II was 65.7+/-5 (57-78), NYHA 3.1+/-0.7, CCS 3.4+/-0.8, LVEF(%) 25+/-5, LVEDP(mmHg) 27.9+/-4.4 and LVEDD(mm) 69.2+/-7.2.

RESULTS

Postoperatively, 5(7.7%) patients died in Group I versus 7(11.5%) patients in Group II (P>0.1). CPB time resulted to be in Group II patients (P=0.001) and the mean distal anastomoses per patient was similar between groups (P=Ns). Perioperative AMI (P=0.039), LCOS (P=0.002), necessity for ultrafiltration (P=0.018) and bleeding>1000 ml (P=0.029) were significantly higher in Group II. None of the Group I patients underwent surgical revision for bleeding versus 8(10.3%) patients in Group II (P=0.011). At 6 months after surgery, the LV function improved significantly in Group I patients, demonstrated by an increased LVEF=27.2+/-4(%)(P=0.001), lower LVEDP=26.4+/-3(mmHg)(P=0.029) and LVEDD=67+/-4(mm) (P=0.004) instead of a lower LVEDD=66.8+/-6(mm)(P=0.032) versus the preoperative data in Group II. The actuarial survival at 1, 3 and 5 yr were 90, 82 and 71% in Group I and 89, 83 and 74% in Group II (P=Ns).

CONCLUSION

In ESCAD patients who may poorly tolerate cardioplegic arrest, on-pump/beating-heart CABG may be an acceptable alternative associated with lower postoperative mortality and morbidity. Such a technique offers a better myocardial and renal protection associated with lower postoperative complications due to intraoperative hypoperfusion.

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.

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.

Should mild-to-moderate and moderate ischemic mitral regurgitation be corrected in patients with impaired left ventricular function undergoing simultaneous coronary revascularization?

INTRODUCTION

Mitral valve regurgitation (MR) occurring as a result of myocardial ischemia and global left ventricular (LV) dysfunction predicts poor outcome. This study assessed the feasibility of mitral valve (MV) surgery concomitant with coronary artery bypass grafting (CABG) in patients with mild-to-moderate and moderate ischemic MR and impaired LV function.

MATERIALS AND METHOD

From January 1996 to July 2000, 49 patients (group 1) and 50 patients (group 2) with grade II and grade III ischemic MR and LV ejection fraction (EF) between 17% and 30% underwent combined MV surgery and CABG (group 1) or isolated CABG (group 2). LVEF (%), LV end-diastolic diameter (EDD) (mm), LV end-diastolic pressure (EDP) (mmHg), and LV end-systolic diameter (ESD) (mm) were 27.5 +/- 5, 67.7 +/- 7,27.7 +/- 4, and 51.4 +/- 7, respectively in group 1 versus 27.8 +/- 4, 67.5 +/- 6, 27.5 +/- 5, and 51.2 +/- 6, respectively in group 2. Groups 1 and 2 were divided into Groups 1A and 2A with mild-to-moderate MR (22 [45%] and 28 [56%] patients, respectively) and groups 1B and 2B with moderate MR (27 [55%] and 22 [46%], respectively). In group 1, MV repair was performed in 43 (88%) patients and MV replacement in 6 (12%) patients.

RESULTS

Preoperative data analysis did not reveal any difference between groups. Five (10%) patients in group 1 died versus 6 (12%) in group 2 (p = ns). Within 6 months after surgery, LV function and its geometry improved significantly in group 1 versus group 2 (LVEF, p < 0.001; LVEDD, p = 0.002; LVESD, p = 0.003; and LVEDP (p < 0.001) improved significantly in group 1 instead of a mild improvement in Group 2). The regurgitation fraction decreased significantly in group 1 patients after surgery (p < 0.001). There was an inverse strong correlation between postoperative forward cardiac output and regurgitation fraction (p < 0.001). LVEF and LVESD improved significantly in group 1 versus group 2 patients (p = 0.04 and p = 0.02, respectively). The cardiac index increased significantly in group 1 and 2 (p < 0.001 and p = 0.03, respectively). LV function and geometry improved significantly postoperatively in group 1B versus group 2B (LVEDD, p = 0.027; LVESD, p = 0.014; LVEDP, p = 0.034; and LVEF, p = 0.02), instead of a mild improvement in group 1A versus group 2A (LVESD, p = 0.015; LVEF, p = 0.046; and LVEDD and LVEDP, p = 0.05). At follow-up, 4 (67%) of 6 patients undergoing MV replacement died versus 5 (11.5%) of 43 patients undergoing MV repair in group 1 (p = 0.007). The overall survival at 3 years in Group 2 was significantly lower than group 1 (p < 0.009).

CONCLUSION

MV repair and replacement-preserving subvalvular apparatus in patients with impaired LV function offered acceptable outcomes in terms of morbidity and survival. Surgical correction of mild-to-moderate and moderate MR in patients with impaired LV function should be taken into consideration since it yields better survival and improved LV function.

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.

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.

Bioavailability of vitamin E as function of food intake in healthy subjects: effects on plasma peroxide-scavenging activity and cholesterol-oxidation products

Clinical trials with vitamin E have yielded contrasting results. In these trials, the amount of vitamin E given was different, and the compliance was not assessed in all studies. In addition, the modality of intake, ie, in relation to food, was not specified in any trial. Vitamin E is lipophilic, and its absorption is expected to be increased by food. We studied the bioavailability of vitamin E in relation to food intake and the effect on the lipid peroxide-scavenging activity of plasma and on 7beta-hydroxycholesterol and 7-ketocholesterol (oxysterols) as markers of oxidant stress. Twenty healthy Italian subjects were randomly assigned to take vitamin E at 300 mg/d on an empty stomach (group A) or during dinner (group B) for 15 days. Plasma vitamin E markedly increased in group B (84%) compared with group A (29%). The lipid peroxide-scavenging activity of plasma increased significantly in group B (14%, P=0.005) but did not change in group A. All subjects showed very low levels of plasma oxysterols, which were not affected by vitamin E supplementation in either group. This study shows that plasma concentration of vitamin E and plasma antioxidant activity in response to oral supplementation are markedly affected by food intake. Healthy Italian subjects show very low levels of cholesterol oxidation products; these low levels are possibly related to the Mediterranean diet. To obtain maximal absorption, vitamin E must be given at meals. These data should be taken into account in clinical trials with vitamin E.

Mutated p21/WAF/CIP transgene overexpression reduces smooth muscle cell proliferation, macrophage deposition, oxidation-sensitive mechanisms, and restenosis in hypercholesterolemic apolipoprotein E knockout mice

We have investigated whether by introducing a mutated p21 cyclin-dependent kinase inhibitor through a standard type 5 adenovirus (Ad), it would be possible to interfere with restenosis in hypercholesterolemic apolipoprotein E knockout mice. Restenosis is a clinically relevant, undesired effect of percutaneous transluminal coronary angioplasty (PTCA). A critical event underlying restenosis is smooth muscle cell (SMC) proliferation leading to neointimal formation and vessel reocclusion. Recent data demonstrated that it is possible to reduce restenosis by introducing various genes blocking the cell cycle through Ad vectors. Nonetheless, most experiments were conducted in the healthy carotid artery of rat, which is far from the condition of human disease. Therefore, we investigated whether antiproliferative or proapoptotic genes affect restenosis in a model of atherosclerosis closer to clinical settings. Ad-mutated(m)-p21WAF/CIP1 transgene overexpression induces a significant reduction of restenosis in hypercholesterolemic apolipoprotein E knockout mice subjected to injury of common carotid artery. This was associated with reduced SMC density and proliferation, macrophage deposition, and oxidation-sensitive mechanisms. Treatment with p21/WAF also enhanced TUNEL positivity of arterial cells. We show that in an experimental model of atherosclerosis, braking the cell proliferation through increased vascular apoptosis and reduced oxidation-sensitive signal transduction and macrophage accumulation can significantly ameliorate the deleterious effects of vascular injuries similar to those that occur during PTCA and related procedures.

Cardiomyocytes induce endothelial cells to trans-differentiate into cardiac muscle: implications for myocardium regeneration

The concept of tissue-restricted differentiation of postnatal stem cells has been challenged by recent evidence showing pluripotency for hematopoietic, mesenchymal, and neural stem cells. Furthermore, rare but well documented examples exist of already differentiated cells in developing mammals that change fate and trans-differentiate into another cell type. Here, we report that endothelial cells, either freshly isolated from embryonic vessels or established as homogeneous cells in culture, differentiate into beating cardiomyocytes and express cardiac markers when cocultured with neonatal rat cardiomyocytes or when injected into postischemic adult mouse heart. Human umbilical vein endothelial cells also differentiate into cardiomyocytes under similar experimental conditions and transiently coexpress von Willebrand factor and sarcomeric myosin. In contrast, neural stem cells, which efficiently differentiate into skeletal muscle, differentiate into cardiomyocytes at a low rate. Fibroblast growth factor 2 and bone morphogenetic protein 4, which activate cardiac differentiation in embryonic cells, do not activate cardiogenesis in endothelial cells or stimulate trans-differentiation in coculture, suggesting that different signaling molecules are responsible for cardiac induction during embryogenesis and in successive periods of development. The fact that endothelial cells can generate cardiomyocytes sheds additional light on the plasticity of endothelial cells during development and opens perspectives for cell autologous replacement therapies.

Heart-targeted overexpression of caspase3 in mice increases infarct size and depresses cardiac function

Up-regulation of proapoptotic genes has been reported in heart failure and myocardial infarction. To determine whether caspase genes can affect cardiac function, a transgenic mouse was generated. Cardiac tissue-specific overexpression of the proapoptotic gene Caspase3 was induced by using the rat promoter of alpha-myosin heavy chain, a model that may represent a unique tool for investigating new molecules and antiapoptotic therapeutic strategies. Cardiac-specific Caspase3 expression induced transient depression of cardiac function and abnormal nuclear and myofibrillar ultrastructural damage. When subjected to myocardial ischemia-reperfusion injury, Caspase3 transgenic mice showed increased infarct size and a pronounced susceptibility to die. In this report, we document an unexpected property of the proapoptotic gene caspase3 on cardiac contractility. Despite inducing ultrastructural damage, Caspase3 does not trigger a full apoptotic response in the cardiomyocyte. We also implicate Caspase3 in determining myocardial infarct size after ischemia-reperfusion injury, because its cardiomyocyte-specific overexpression increases infarct size.

Impaired insulin-like growth factor I vasorelaxant effects in hypertension

Insulin-like growth factor I (IGF-I) can be considered a factor potentially involved in arterial hypertension not only for its growth-promoting features but also for its effects on vascular tone. Nevertheless, the actions of the hormone on vascular reactivity are still unexplored in hypertension. Therefore, the vasodilation induced by increasing doses of IGF-I and the modulation of norepinephrine vasoconstriction induced by low levels of the hormone were tested on aortic rings of spontaneously hypertensive and normotensive rats. The results indicate that the vasodilation evoked by IGF-I is impaired in hypertensive rats (Delta% of maximal vasorelaxation, 30+/-1 versus 41+/-1; P<0.01), and after the removal of endothelium or the inhibition of endothelial NO synthase, the vasodilation evoked by the hormone was blunted in both rat strains and became similar between hypertensive and normotensive rats (Delta% of maximal vasorelaxation, 21+/-1 versus 20+/-1; P=NS). Moreover, IGF-I does not show any effect on norepinephrine vasoconstriction in hypertensive rats, and this alteration may depend on the lack of sensitizing effect exerted by IGF-I on alpha(2)-adrenergic-evoked NO vasorelaxation. The defect in IGF-I vascular action is also present in young spontaneously hypertensive rats (age 5 weeks). In conclusion, our data demonstrate that IGF-I vasorelaxant properties are impaired in spontaneously hypertensive rats, suggesting that such defect may play a causative or permissive role in the development of hypertensive conditions.

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.

A common variant of endothelial nitric oxide synthase (Glu298Asp) is an independent risk factor for carotid atherosclerosis

BACKGROUND AND PURPOSE

Endothelium-derived NO is formed from L-arginine by endothelial NO synthase (eNOS) encoded by the NOS 3 gene on chromosome 7. Because several studies have indicated that NO plays a key role in the development of the atherosclerotic process, we investigated whether common variants in the eNOS gene are associated with an increased risk of plaque on carotid arteries.

METHODS

We studied 375 subjects attending the hypertension center of our institution to be screened for arterial hypertension. The examined subjects were classified according to the presence of carotid plaques (intima-media thickness >/=1.5 mm), and 2 intronic (CA and 27-bp repeats) polymorphisms and 1 exonic (Glu298Asp) polymorphism of the eNOS gene were explored.

RESULTS

Only the Glu298Asp polymorphism of eNOS was associated with the presence of carotid plaques (P:<0.05). In particular, there was an excess of homozygotes for the Asp298 variant among subjects with carotid plaques, whereas the number of subjects who had the Glu298 allele in exon 7 of the eNOS gene was equally distributed in both study groups. Interestingly, the risk of having carotid plaques was increased approximately 3 times in subjects who were homozygotic for the Asp298 variant compared with subjects who were homozygotic for the Glu298 variant and was independent of the other common risk factors (age, blood pressure, and smoking).

CONCLUSIONS

Homozygosity for Asp298, a common variant of the eNOS gene, is an independent risk factor for carotid atherosclerosis in this study population.

Proximal aortic dissection with coronary malperfusion: presentation, management, and outcome

BACKGROUND

Acute myocardial ischemia and infarction due to retrograde dissection of the aortic root reaching the coronary ostia is a potentially fatal condition. Surgical treatment of these patients relies on the re-establishment of an adequate coronary blood flow and on the rescue of jeopardized myocardium. This article reports the results of a selected group of 24 patients with type A acute aortic dissection and coronary artery dissection. We review our experience and illustrate our approach to this condition, which evolved over a 15-year period.

METHODS

Between July 1985 and March 2000, 24 patients from a total of 211 (11.3%) treated for acute type A aortic dissection had dissection of at least one of the coronary ostia. There were 14 men and 10 women. The mean age was 65.5 years (median 61.7; range 41-78 years). The right coronary artery was involved in 11 patients, the left in 4 patients, and both coronary arteries in 9 patients. At admission, 16 patients had Q waves (66%), inferior in 6 (25%) and anterior, lateral, septal, or posterior in 10 (41%). All procedures were done on an emergency basis within 10 hours (median 4 hours) after initial chest pain and within 2 hours after the patient's arrival.

RESULTS

Hospital mortality was 20% (5 patients); 3 patients could not be weaned from cardiopulmonary bypass and died intraoperatively, and 2 patients died postoperatively of low cardiac output.

CONCLUSIONS

As illustrated in this study, direct coronary repair is a safe alternative to bypass grafting. Aggressive myocardial resuscitation together with early operation is a key factor in the management of these patients.

Total mesorectal excision and low rectal anastomosis for the treatment of rectal cancer and prevention of pelvic recurrences

HYPOTHESIS

Total mesorectal excision lowers the rate of pelvic recurrence and positively affects the survival after surgical treatment of rectal cancer.

DESIGN

Case series.

SETTING

Tertiary care university hospital.

PATIENTS

Fifty-three consecutive patients were admitted with curative intent to surgery at the First Department of Surgery of the University of Rome "La Sapienza," Rome, Italy, with diagnoses of rectal carcinoma. The mean follow-up was 68.9 months; follow-up was complete for all patients who entered the trial.

INTERVENTIONS

Low anterior resection and total mesorectal excision were performed in all cases, regardless of the location of the rectal cancer. A straight mechanical colorectal anastomosis was performed on a rectal stump, never exceeding 5 cm. No kind of adjuvant therapy was given. Mesorectum and open rectum were studied by serial transverse section at 5-mm intervals. A search for depth of penetration and distal intramural extension of the tumor was made. Lymph nodes were detected by clearing method, and nodal metastases (NM) and nonnodal metastases (NNM) were recorded as situated proximally, distally, or at the level of the tumor.

RESULTS

There was no postoperative mortality. Clinical and radiologic leaks occurred in 2 and 4 patients, respectively. Mean disease-free survival was 65.9 months. Pelvic recurrence occurred in 5 patients (9%). Overall 5-year survival rate was 75%. Involvement of mesorectum by NM and NNM was detected in 27 and 24 cases, respectively. Both NM and NNM were found to be distal in 33% and 40% of cases, respectively.

CONCLUSIONS

Microscopic spread to the distal mesorectum may exceed the intramural spread of rectal cancer. Failure to perform total mesorectal excision leaves a potentially residual disease in the distal mesorectum, thus predisposing the patient to pelvic recurrence.

The elephant trunk technique: a new complication

We describe a complication that occurred during the 2nd stage of an "elephant trunk " aortic replacement. The patient was a 58-year-old woman who had undergone graft replacement of the ascending aorta and aortic arch with the elephant trunk technique for an acute, Stanford type-A aortic dissection.

Latrogenic injury to the longthoracic nerve: an underestimated cause of morbidity after cardiac surgery

After heart surgery, complications affecting the brachial plexus have been reported in 2% to 38% of cases. The long thoracic nerve is vulnerable to damage at various levels, due to its long and superficial course. This nerve supplies the serratus anterior muscle, which has an important role in the abduction and elevation of the superior limb; paralysis of the serratus anterior causes "winged scapula," a condition in which the arm cannot be lifted higher than 90 degrees from the side. Unfortunately the long thoracic nerve can be damaged by a wide variety of traumatic and nontraumatic occurrences, ranging from viral or nonviral disease to improper surgical technique, to the position of the patient during transfer to a hospital bed. Our patient, a 62-year-old man with triple-vessel disease, underwent myocardial revascularization in which right and left internal thoracic arteries and the left radial artery were grafted to the right coronary, descending anterior, and obtuse marginal arteries, respectively. Despite strong recovery and an apparently good postoperative course, the patient sued for damages due to subsequent winging of the left scapula. In this instance, the legal case has less to do with the cause of the lesion (which remains unclear) than with failure to adequately inform the patient of possible complications at the expense of the nervous system. The lesson is that each patient must receive detailed written and oral explanation of the potential benefits and all conceivable risks of a procedure.

A simple method to prevent calcium embolization during aortic valve surgery

Calcium embolization is a potential complication of aortic valve surgery Handling and debridement of calcified structures may lead to dislodgment of particles, which can fall into the left ventricular chamber With restoration of the heartbeat, these particles are ejected into the systemic circulation, with subsequent peripheral or coronary embolism. We have developed a simple and safe method to prevent this condition; in our practice, we have found this method to be very effective.

Cocaine-induced intramural hematoma of the ascending aorta

We report the case of a 35-year-old man who presented at our institution with intramural aortic hematoma shortly after inhaling cocaine and smoking crack cocaine. To our knowledge, such a case has not previously been reported in the English medical literature. Problems of diagnosis and the mechanisms of intramural hematoma and aortic dissection are discussed.