Vasomotion as an oscillatory sign of functional impairment in the human internal thoracic artery: A study based on risk factors and vessel reactivity.

NEW FINDINGS: What is the central question of this study? Vasomotion has been viewed as a rhythmic oscillation of the vascular tone that is physiologically important for optimal tissue perfusion. Also, it has been studied primarily in the microcirculation. However, the precise underlying mechanisms and the physiological significance remain unknown. What is the main finding and its importance? Vasomotion is not specific to the microcirculation, as shown by our findings. In human arteries from patients undergoing cardiac surgery, an increased incidence was associated with endothelial dysfunction settings. Therefore, this oscillatory behaviour might be a signal of functional impairment and not of integrity. ABSTRACT: Vasomotion has been defined as the rhythmic oscillation of the vascular tone, involved in the control of the blood flow and subsequent tissue perfusion. Our aims were to study the incidence of vasomotion in the human internal thoracic artery and the correlation of this phenomenon with the clinical profile and parameters of vascular reactivity. In our study, vasomotion was elicited with a single-dose contractile stimulation of noradrenaline (10 µm) in internal thoracic artery segments, from patients undergoing coronary artery bypass grafting, mounted in tissue organ bath chambers. The incidence was 29.1%. Vessel samples with vasomotion presented significantly higher contractility in response to both potassium chloride (maximal response or Emax of 7.65 ± 5.81 mN versus 4.52 ± 3.73 mN in control vessels, P = 0.024) and noradrenaline (Emax of 7.60 ± 5.93 mN versus 2.96 ± 4.41 mN in control vessels, P < 0.001). Predictive modelling through multivariable logistic regression analysis showed that female sex (odds ratio = 9.82) and increasing maximal response to noradrenaline (odds ratio = 1.19, per 1 mN increase) were associated with a higher probability of the occurrence of vasomotion, whereas increasing kidney function (expressed as estimated glomerular filtration rate) was associated with a lower probability (odds ratio = 0.97, per 1 ml min-1  (1.73 m)-2 ]. Our results provide a characterization of the phenomenon of vasomotion in the internal thoracic artery and suggest that vasomotion might be associated with endothelial dysfunction settings, as determined by a multivariable analysis approach. Considering the associations observed in our results, vasomotion might be a signal of functional impairment and not of integrity.

Vascular effects of Fragaria vesca L. in human arteries.

Fragaria vesca L. (wild strawberry) is traditionally used for its anti-inflammatory activity and for gastrointestinal, cardiovascular and urinary disorders. A previous study with the rat aorta showed that its leaves extract elicits endothelium-dependent vasorelaxation. Our aim was to investigate the clinical application of Fragaria vesca in vascular disease, by assessing the vascular effects of an infusion and hydroalcoholic extract in internal thoracic arteries from patients with coronary artery disease. The extracts elicited no effects on basal vascular tone and did not induce any vasorelaxation. At low concentration (0.02 mg/mL), the infusion potentiated the noradrenaline-induced contraction, while the other concentrations did not elicit significant changes in efficacy or potency. Differences between our findings and the previous report on rat aorta may result from methodological differences, e.g. vascular bed, method of extraction and extract composition. The clinical applicability of extracts of Fragaria vesca in patients with cardiovascular disease remains to be fully validated.

Vascular Effects of Polyphenols from Agrimonia eupatoria L. and Role of Isoquercitrin in Its Vasorelaxant Potential in Human Arteries.

Agrimonia eupatoria L. has been traditionally used for the treatment of inflammatory diseases but also as a hypotensive. To our knowledge, only one study has previously suggested an improvement in vascular endothelial function in diabetic conditions, as the underlying mechanisms and responsible compounds are unknown. In this study, we aimed to assess the direct vascular effects of Agrimonia eupatoria L. in human arteries. The infusion elicited a mild increase in basal vascular tone and a significant potentiation of the adrenergic contraction of 49.18% at 0.02 mg/mL, suggesting the presence of compounds with mild vasoconstrictor activity. In contrast, the ethyl acetate fraction inhibited adrenergic contraction by 80.65% at 2 mg/mL and elicited no effect on basal vascular tone. A potent concentration-dependent vasorelaxation was observed for both the infusion and the ethyl acetate fraction (maximal relaxation above 76% and 47%, respectively). Inhibition of nitric oxide synthase and cyclooxygenase elicited significant decreases in the vasorelaxation to the infusion, as, for the ethyl acetate fraction, only the cyclooxygenase pathway appeared to be involved. Isoquercitrin elicited a vasoactivity consistent with the ethyl acetate fraction, suggesting this is a major component responsible for the vasorelaxant properties of A. eupatoria. Further research is warranted to fully evaluate its vasoprotective properties with therapeutic potential in several conditions, e.g., atherosclerosis.

Risk-Prediction Model for Transfusion of Erythrocyte Concentrate During Extracorporeal Circulation in Coronary Surgery.

INTRODUCTION: Our objective was to identify preoperative risk factors and to develop and validate a risk-prediction model for the need for blood (erythrocyte concentrate [EC]) transfusion during extracorporeal circulation (ECC) in patients undergoing coronary artery bypass grafting (CABG). METHODS: This is a retrospective observational study including 530 consecutive patients who underwent isolated on-pump CABG at our Centre over a full two-year period. The risk model was developed and validated by logistic regression and bootstrap analysis. Discrimination and calibration were assessed using the area under the receiver operating characteristic curve (AUC) and the Hosmer-Lemeshow (H-L) test, respectively. RESULTS: EC transfusion during ECC was required in 91 patients (17.2%). Of these, the majority were transfused with one (54.9%) or two (41.8%) EC units. The final model covariates (reported as odds ratios; 95% confidence interval) were age (1.07; 1.02-1.13), glomerular filtration rate (0.98; 0.96-1.00), body surface area (0.95; 0.92-0.98), peripheral vascular disease (3.03; 1.01-9.05), cerebrovascular disease (4.58; 1.29-16.18), and hematocrit (0.55; 0.48-0.63). The risk model developed has an excellent discriminatory power (AUC: 0,963). The results of the H-L test showed that the model predicts accurately both on average and across the ranges of deciles of risk. CONCLUSIONS: A risk-prediction model for EC transfusion during ECC was developed, which performed adequately in terms of discrimination, calibration, and stability over a wide spectrum of risk. It can be used as an instrument to provide accurate information about the need for EC transfusion during ECC, and as a valuable adjunct for local improvement of clinical practice. Key Findings: Risk factors with the greatest prediction for EC transfusion. Take-Home Message: The implementation of this model would be an important step in optimizing and improving the quality of surgery.

Cardiac transplantation: five years' activity.

OBJECTIVE: To analyze the initial five years experience of the new heart transplant program of Coimbra University Hospitals. METHODS: Between November 2003 aid December 2008, 132 patients were transplanted, with a mean age of 52.0 years (range 3-71 years), of whom 98 were male (74%). Half of the patients had dilated cardiomyopathy and 33% ischemic cardiomyopathy. The mean age of donors was 31.7 years and 102 were male (77%). Donor hearts were harvested at a distance in 62% of cases. There was a gender mismatch between donor and recipient (F:M) in 19% of cases and ABO blood type disparity (not identical but compatible) in 11%. In all cases we used the technique of total transplantation with bicaval anastomosis, modified in this center. Mean ischemia time was 88.9 +/- 32.2 minutes. All patients received induction therapy with basiliximab and methylprednisolone. RESULTS: Six patients (4.5%) died within 30 days or during hospitalization, due to graft failure in four and hyperacute rejection in two. Two patients required prolonged ventilation, ten (8%) required inotropic support for more than 48 hours, and four required pacemaker implantation. Mean hospital stay was 15.6 +/- 15.2 days (median 13 days). Ninety percent of patients (116/129) were maintained on triple immunosuppressive therapy, including cyclosporine, the remainder receiving tacrolimus. In 23 patients it was necessary to change the immunosuppressive regimen due to renal and/or tumoral complications, or humoral rejection. All patients are followed regularly in the Surgical Center. Thirteen patients (10%) died late of cancer (6 patients), infection (4 patients), and pancreatitis, pulmonary hypertension and suicide (one patient each). Twenty-two patients (17%) had 25 episodes of cellular rejection (> or = 2R), with clinical consequences in only one case, and five had humoral rejection (3.9%). No patients died of late rejection, but there is evidence of mild graft vascular disease in one. Actuarial survival (Kaplan-Meier) at one and five years was 90% and 82%, respectively. CONCLUSION: In this initial series of five years we obtained results equivalent to or bette than those in centers with wider and longer experience, aided by self-correction arising from our own experience. This program has increased the rate of cardiac transplantation in Portugal to above the European average.

Vascular activity of infusion and fractions of Cymbopogon citratus (DC) Stapf. in human arteries.

ETHNOPHARMACOLOGICAL RELEVANCE: Cymbopogon citratus (DC.) Stapf has been traditionally used mainly for inflammatory diseases and hypertension. However, the mechanisms underlying its vascular activity remain to be fully characterized and the fractions responsible for its cardiovascular activity are still unknown. AIM OF THE STUDY: In this study, we aimed to assess the vascular activity of Cymbopogon citratus in human arteries and to study the role of cyclooxygenase in its vasorelaxant effects. MATERIALS AND METHODS: Vascular effects of leaves infusion and three fractions (phenolic acids, flavonoids and tannins) were studied using distal segments of human internal thoracic arteries harvested from patients undergoing coronary revascularization, which were mounted as rings in tissue organ baths and maintained at 37 °C in Krebs Henseleit buffer. The effect on basal vascular tone, the effect on the noradrenaline-induced contraction and the vasorelaxant effects were assessed. The role of cyclooxygenase was evaluated with indomethacin. RESULTS: Our results showed a mild effect on the basal vessel tone of the infusion. A significant inhibition on the adrenergic-mediated vasoconstriction was observed for the infusion (0.0002 mg/mL) and the flavonoid fraction (0.2 mg/mL), despite a potentiation was observed in some conditions. A vasorelaxant effect was observed for both the infusion (6.46% of maximal relaxation) and the tannin fraction (26.91% of maximal relaxation, P < 0.05 vs. infusion). Incubation with indomethacin (10 µM) elicited a decrease in the vasorelaxation to the infusion (P < 0.05). CONCLUSIONS: These results suggest that cyclooxygenase may be involved in the vasorelaxation to the infusion of Cymbopogon citratus and that tannins are the compound fraction mainly responsible for this vasorelaxation.

Vascular effects of a polyphenolic fraction from Oxalis pes-caprae L.: role of α-adrenergic receptors Sub-types.

Oxalis pes-caprae L. is a plant of the Oxalidaceae family, from which several compounds have been previously identified. Recently, we showed that an Oxalis pes-caprae L. extract inhibits the vasopressor effect of noradrenaline. In this work we aimed to explore the mechanisms involved in this effect. The results confirmed that the flavonoid fraction present in the extract inhibits noradrenaline-induced contractions and that this effect is concentration-dependent. Also, a parallel shift to the right in the noradrenaline concentration-response curve was observed, suggesting a decrease in efficacy and also in potency. Together these results support the assumption that the extract could exert a non-competitive antagonism on the α-adrenergic receptors. However, experiments in the presence of competitive antagonists for α-adrenergic receptor sub-types (i.e. prazosin, yohimbine and phentolamine) showed that the effect may not be directly mediated by α-adrenergic receptors. Thus, the interaction of this extract with the adrenergic system remains to be confirmed.

Histomorphometric analysis of the human internal thoracic artery and relationship with cardiovascular risk factors.

In this study, we aimed at performing a histomorphometric analysis of human left internal thoracic artery (ITA) samples as well as at correlating the histomorphometric findings with the clinical profile, including risk factors and medication. Distal segments of ITA were obtained from 54 patients undergoing coronary artery bypass grafting. Histological observation was performed in paraffin-embedded transverse sections of ITA through four staining protocols: hematoxylin-eosin, van Gieson, Masson's trichrome and von Kossa. Morphometric analysis included the intimal width (IW), medial width (MW) and intima/media ratio (IMR). No overt atherosclerotic lesions were observed. Mild calcifications were observed across the vascular wall layers in almost all samples. Multivariable linear regression analysis showed associations between IW and IMR and the following clinical variables: age, gender, kidney function expressed as eGFR and myocardial infarction history. Age (odds ratio = 1.16, P = 0.004), female gender (odds ratio = 11.34, P = 0.011), eGFR (odds ratio = 1.03, P = 0.059) and myocardial infarction history (odds ratio = 4.81, P = 0.040) were identified as the main clinical predictors for intimal hyperplasia. Preatherosclerotic lesions in ITA samples from patients undergoing coronary revascularization were associated not only with classical cardiovascular risk factors such as age and gender, but also with other clinical variables, namely kidney function and myocardial infarction history.

MDMA modulates 5-HT1-mediated contractile response of the human internal thoracic artery in vitro.

3,4-Methylenedioxymethamphetamine (MDMA or "ecstasy") is a popular recreational drug of abuse. In addition to its characteristic psychotropic effects, important cardiovascular effects have been described such as increased blood pressure and heart rate. MDMA was previously shown to behave as a partial agonist on 5-hydroxytryptamine (5-HT) receptors in the human internal thoracic artery in vitro, involving the 5-HT2A subtype. Here, we studied the interaction of MDMA (400, 800 and 1600 µM) with the following 5-HT receptor agonists: 5-carboxamidotryptamine (5-CT, full agonist for the 5-HT1, 5-HT2, 5-HT5, 5-HT6 and 5-HT7 receptors) and sumatriptan (selective 5-HT1B/1D receptors agonist). The results showed the ability of MDMA to influence the concentration-dependent response of 5-CT (97.3% of maximal reduction for 1600 µM of MDMA) and sumatriptan (72.43% of maximal reduction for 1600 µM of MDMA). The lower concentration of MDMA (400 µM) produced a significant potentiation of the response to sumatriptan thus suggesting an interaction of MDMA with the activation of 5-HT receptors, namely of the 5-HT1 subtype, in the peripheral vasculature. Together our results further support the importance of the affinity of MDMA to 5-HT receptors in the vascular effects of this drug.

Coronary surgery in patients with diabetes mellitus: a risk-adjusted study on early outcome.

OBJECTIVES: We aimed at determining the effect of diabetes mellitus (diabetes) on short-term mortality and morbidity in a cohort of patients with ischemic disease undergoing coronary artery bypass surgery (CABG) at our institution. MATERIAL AND METHODS: A total of 4567 patients undergoing isolated CABG in a 10-year period were studied. Diabetes mellitus was present in 22.6% of the cases but the percentage increased from 19.1% in the beginning to 27% in the end of the study period (p<0.0001 for the decade time-trend). Compared with non-diabetic patients, the group with diabetes was older (61.5+/-8.4 years vs 60.4+/-9.5 years), had a higher body mass index (26.4+/-2.2 vs 26.0+/-2.2), comprised more women (17.5% vs 10.1%), and had a greater incidence of peripheral vascular disease (13.3% vs 8.8%), cerebrovascular disease (8.3% vs 4.3%), renal failure (2.7% vs 1.1%), cardiomegaly (14.0% vs 10.9%), class III-IV angina (43.4% vs 39.0%), triple-vessel disease (80.9% vs 73.7%) and patients with left ventricular dysfunction (all p<0.05). Demographic and peri-procedural data were registered prospectively in a computerized institutional database. Multivariate logistic regression was performed to assess the influence of diabetes as an independent risk factor for in-hospital mortality and morbidity. RESULTS: The overall in-hospital mortality was 0.96% [n=44; diabetics: 1.0%, non-diabetics: 0.9% (p=0.74)]. The mortality of patients with diabetes decreased from 2.7% in the early period to 0.7% in the late period (p=0.03 for the time-trend). Postoperative in-hospital complications were comparable in the two groups in univariate analysis, with only cerebrovascular accident and prolonged length of stay being significantly higher in the diabetic patients (all p<0.05). In multivariate analysis, diabetes was not found to be an independent risk factor for in-hospital mortality (OR=0.61; 95% CI=0.28-1.30; p=0.19), but predicted the occurrence of mediastinitis (OR=1.80; 95% CI=1.01-3.22; p=0.049). CONCLUSIONS: Despite worse demographic and clinical characteristics, diabetic patients could be surgically revascularized with low mortality and morbidity, comparable with control patients. Hence, our data do not support diabetes as a risk factor for significantly adverse early outcome following CABG.

Coronary artery bypass surgery in young adults: excellent perioperative results and long-term survival.

OBJECTIVES: To analyse perioperative results, long-term survival and freedom from complications after coronary artery bypass grafting (CABG) in young adults. METHODS: A total of 163 patients, 40 years old or younger, had isolated CABG from January 1989 to December 2010. Pre- and perioperative demographic and clinical data were retrieved from a prospectively organised database. Follow-up data were obtained by letter or telephone interviews. The mean age of the patients was 37.6 ± 2.9 years and 146 were men (90%). Fifty-three patients (32.5%) had angina class III/IV; 106 (65.0%), previous myocardial infarction; and 23 (14.1%), impaired left ventricular function (ejection fraction <40%). Indication for surgery was 3-vessel disease in 101 cases (62.0%), 2-vessel disease in 30 (18.4%) and single-vessel disease in 32 (19.6%). The left main stem was affected in 16 patients (9.8%). The mean EuroSCORE II was 0.92 ± 0.71. A total of 417 grafts were constructed (mean 2.6 grafts/patient), 247 of which (59.2%) were arterial. RESULTS: There were no in-hospital deaths. The mean hospital stay was 7.1 ± 4.0 days. Four patients (2.5%) were lost to follow-up, which extended from 3 to 25 years (mean 15.1 ± 5.5 years). There were 22 late deaths, 72.7% of cardiac or unknown origin. The 5-, 10- and 20-year survival rates were 98.7 ± 10.9, 95.2 ± 1.8 and 79.4 ± 4.4%, respectively. Twenty-six patients (18.1%) had non-fatal cardiac adverse complications (myocardial infarct, percutaneous re-revascularization or class III/IV angina), for 5-, 10- and 20-year freedom from complications of 97.9 ± 1.2, 91.9 ± 2.5 and 65.7 ± 7.1%, respectively. Twenty-two patients (17.5%) needed re-revascularization, for 5-, 10- and 20-year freedom from re-revascularization of 97.6 ± 1.4, 91.9 ± 2.6 and 69.5 ± 6.7%, respectively. CONCLUSIONS: Despite the aggressive nature of coronary artery disease in young patients, perioperative death and morbidity rates are low, with good long-term survival and low rates of re-revascularization.

Ultrastructural and histomorphologic properties of the internal thoracic artery: implications for coronary revascularization.

Coronary artery disease represents a major health problem worldwide for which coronary artery bypass surgery remains a standard of care. Among the several grafts that are available, the internal thoracic artery (ITA) has long been considered the best as several advantages have been described compared with other vessels (e.g. saphenous vein or radial artery), namely, an absent to minor atherosclerotic development. In fact, several studies showed the presence of preatherosclerotic lesions, such as intimal and/or medial thickening, medial fibrosis, among others, in the presence of certain cardiovascular risk factors as well as established atherosclerotic lesions (i.e. type II or more lesions). This paper primarily aimed at reviewing the current knowledge on the histomorphological characteristics of ITA as well as the comparative histomorphology of ITA with other vessel grafts currently in use in coronary surgery. As some of the evidence is not clear or consensual, this paper also aimed at reviewing the main histopathological, histomorphometrical, and ultrastructural findings in ITAs from patients with known cardiovascular risk factors (e.g. aging, obesity, hypertension, diabetes, smoking, and others). As the presence of preatherosclerotic and/or atherosclerotic lesions may compromise the success of the myocardial revascularization and lead to graft failure, contributing toward the associated morbidity and/or mortality, it is essential to improve the scientific knowledge on the structural characterization of ITAs and its correlation with the cardiovascular risk profile.

Risk-Prediction Model for Transfusion of Erythrocyte Concentrate During Extracorporeal Circulation in Coronary Surgery

Abstract Introduction: Our objective was to identify preoperative risk factors and to develop and validate a risk-prediction model for the need for blood (erythrocyte concentrate [EC]) transfusion during extracorporeal circulation (ECC) in patients undergoing coronary artery bypass grafting (CABG). Methods: This is a retrospective observational study including 530 consecutive patients who underwent isolated on-pump CABG at our Centre over a full two-year period. The risk model was developed and validated by logistic regression and bootstrap analysis. Discrimination and calibration were assessed using the area under the receiver operating characteristic curve (AUC) and the Hosmer-Lemeshow (H-L) test, respectively. Results: EC transfusion during ECC was required in 91 patients (17.2%). Of these, the majority were transfused with one (54.9%) or two (41.8%) EC units. The final model covariates (reported as odds ratios; 95% confidence interval) were age (1.07; 1.02-1.13), glomerular filtration rate (0.98; 0.96-1.00), body surface area (0.95; 0.92-0.98), peripheral vascular disease (3.03; 1.01-9.05), cerebrovascular disease (4.58; 1.29-16.18), and hematocrit (0.55; 0.48-0.63). The risk model developed has an excellent discriminatory power (AUC: 0,963). The results of the H-L test showed that the model predicts accurately both on average and across the ranges of deciles of risk. Conclusions: A risk-prediction model for EC transfusion during ECC was developed, which performed adequately in terms of discrimination, calibration, and stability over a wide spectrum of risk. It can be used as an instrument to provide accurate information about the need for EC transfusion during ECC, and as a valuable adjunct for local improvement of clinical practice. OR=odds ratio Key Question: What is the risk of the need for use of erythrocyte concentrate (EC) during cardiopulmonary bypass? Key Findings: Risk factors with the greatest prediction for EC transfusion. Take-Home Message: The implementation of this model would be an important step in optimizing and improving the quality of surgery.

Coronary artery bypass surgery without cardioplegia: hospital results in 8515 patients†.

OBJECTIVES: Cardioplegic myocardial protection is used in most cardiac surgical procedures. However, other alternatives have proved useful. We analysed the perioperative results in a large series of patients undergoing coronary artery bypass (CABG) using cardiopulmonary bypass (CPB) and non-cardioplegic methods. METHODS: From January 1992 to October 2013, 8515 consecutive patients underwent isolated CABG with CPB without cardioplegia, under hypothermic ventricular fibrillation and/or an empty beating heart. The mean age was 61.9 ± 9.5 years, 12.4% were women, 26.3% diabetic, 64% hypertensive; and 9.6% had peripheral vascular disease, 7.8% cerebrovascular disease and 54.3% previous acute myocardial infarction (AMI). One-third of patients were in Canadian Cardiovascular Society Class III/IV. Three-vessel disease was present in 76.5% of the cases and 10.9% had moderate/severe left ventricle (LV) dysfunction (ejection fraction <40%). A multivariate analysis was made of risk factors associated to in-hospital mortality and three major morbidity complications [cerebrovascular accident, mediastinitis and acute kidney injury (AKI)], as well as for prolonged hospital stay. RESULTS: The mean CPB time was 58.2 ± 20.7 min. The mean number of grafts per patient was 2.7 ± 0.8 (arterial: 1.2 ± 0.5). The left internal thoracic artery (ITA) was used in 99.4% of patients and both ITAs in 23.1%. The in-hospital mortality rate was 0.7% (61 patients), inotropic support was required in 6.6% and mechanical support in 0.8, and 2.0% were re-explored for bleeding and 1.3% for sternal complications (mediastinitis, 0.8%). AKI, the majority transient, occurred in 1595 patients (18.9%). The incidence rates of stroke/transient ischemic attack (TIA) and acute myocardial infarction (AMI) were 2.6 and 2.5%, respectively, and atrial fibrillation/flutter occurred in 22.6% of cases. Age, LV dysfunction, non-elective surgery, previous cardiac surgery, peripheral vascular disease and CPB time were independent risk factors for mortality and major morbidity. The mean hospital stay was 7.2 ± 5.7 days. CONCLUSIONS: Isolated CABG with CPB using non-cardioplegic methods proved very safe, with low mortality and morbidity. These methods are simple and expeditious and remain as very useful alternative techniques of myocardial preservation.

Left ventricular aneurysms: early and long-term results of two types of repair.

OBJECTIVE: Controversy still exists regarding the optimal surgical technique for postinfarction left ventricular (LV) aneurysm repair. We analyze the efficacy of two established techniques, linear vs. patch remodeling, for repair of dyskinetic LV aneurysms. METHODS: Between May 1988 and December 2001, 110 consecutive patients underwent repair of LV aneurysms. These represent 2.0% of a total group of 5429 patients who underwent isolated CABG during the period. Seventy-six (69.1%) patients were submitted to linear repair and 34 (30.9%) to patch remodelling. There were 94 (84.5%) men and 17 women, with a mean age of 59.2+/-9.2 years. Coronary surgery was performed in all patients (mean no. of grafts/patient, 2.7+/-0.8) and 14 (12.7%) had associated coronary endarterectomy. Forty-four (40.0%) patients had angina CCS class III/IV (linear 43.4%, patch 32.4%, NS) and the majority was in NYHA class I/II (88.2% in both groups). Left ventricular dysfunction (EF>40%) was present in 72 (65.5%) patients (linear 61.8%, patch 73.5%, NS). RESULTS: There was no perioperative mortality, and major morbidity was not significantly different between linear repair and patch repair groups. During a mean follow-up of 7.3+/-3.4 years (range 4-182 months) 14 patients (14.3%) had died, 12 (85.7%) of possible cardiac-related cause. Actual global survival rate was 85.7%. Actuarial survival rates at 5, 10 and 15 years were 91.3, 81.4 and 74%, respectively. There was no significant difference in late survival between the patch and the linear groups. At late follow-up the mean angina and NYHA class were, 1.3 (preoperative 2.4, P<0.001) and 1.5 (preoperative 1.7, NS), respectively, with no difference between the groups. There was no significant difference in hospital readmissions for cardiac causes (linear 22.8% and patch 37.0%). CONCLUSIONS: The technique of repair of postinfarction dyskinetic LV aneurysms should be adapted in each patient to the cavity size and shape, and the dimension of the scar. Both techniques achieved good results with respect to perioperative mortality, late functional status and survival.

Preservation of the subvalvular apparatus during mitral valve replacement of rheumatic valves does not affect long-term survival.

OBJECTIVES: The importance of preservation of the subvalvular apparatus (PSVA) during mitral valve replacement (MVR) in non-rheumatic mitral valves is well recognized. Our aim was to analyse the impact of PSVA in MVR for rheumatic valves on long-term survival. METHODS: From January 1992 to December 2012, 605 consecutive patients with rheumatic mitral valve disease were submitted to MVR. PSVA (limited to the posterior leaflet) was achieved in 224 (37.7%) patients. Follow-up was 4259 patient-years, and complete for 97% of the patients. Propensity score analysis was introduced to reduce selection bias. RESULTS: Patients with PSVA were slightly older (61.9 vs 59.8 years, P = 0.014), with lower incidence of calcification (54.9 vs 63.0%, P = 0.05), pure mitral stenosis (29.9 vs 38.9%, P = 0.014) and history of rheumatic fever (44.6 vs 53.9%, P = 0.028). Mechanical prostheses were more frequently implanted in the Non-PSVA group (75.1 vs 65.6%, P = 0.013). Thirty-day mortality was 1.1%. Late survival rates at 5, 10 and 18 years were 86.6 ± 2.0, 70.8 ± 3.2 and 48.0 ± 5.1%, respectively, with no difference between groups. Both groups had compromised late survival when compared with the general population (age and gender matched, P < 0.001). Only age, large left atrium, pulmonary hypertension and 'pure' MR appeared as independent predictors for late mortality. There was no difference regarding adverse valve-related events between groups. CONCLUSIONS: Patients submitted to MVR for rheumatic mitral valve disease have a poor prognosis, independently of having the subvalvular apparatus preserved. PSVA did not improve late survival in this setting.

Predictors of cerebrovascular events in patients subjected to isolated coronary surgery. The importance of aortic cross-clamping.

OBJECTIVE: Stroke is a major complication after coronary surgery, occurring in 1-4% of the patients. In this study, we evaluate the incidence and pre- and intraoperative risk factors for the development of a cerebrovascular accident (CVA) and the impact of such an event on perioperative mortality and on hospital length of stay. METHODS: Data from 4567 patients submitted to isolated coronary artery bypass grafting (CABG) with hypothermic ventricular fibrillation between 1992 and 2001 were entered prospectively into a dedicated computerized database and analyzed retrospectively at this time. Univariate and multivariate analyses were performed where appropriate. RESULTS: The incidence of postoperative CVA was 2.5% (116 patients). Multivariable logistic regression identified the following variables to be independent predictors of a postoperative CVA: cerebrovascular disease (P<0.001; odds ratio (OR), 2.66), peripheral vascular disease (P<0.001; OR, 2.33), number of periods of aortic cross-clamping (P=0.019; OR, 1.31 per each period of aortic cross-clamping), LV dysfunction (P=0.012; OR, 1.82) and age (P=0.008; OR, 1.28 per each 10 years). Non-elective surgery showed a marginal significance (P=0.08; OR 1.83). The 30-day mortality for patients who experienced a CVA was 16.4% versus 0.6% for patients who did not (P<0.001). Postoperative CVA increased the length of hospital stay threefold to 20.3+/-28.3 days as compared with patients who did not have a postoperative CVA (7.6+/-4.2 days; P<0.001). CONCLUSIONS: Postoperative CVA dramatically increases the mortality and length of stay after CABG. Identification of predisposing factors permits preoperative risk stratification and may facilitate improved patient selection or optimization. Our study adds evidence to the superiority of the fibrillation technique over intermittent cross-clamping of the aorta, among non-cardioplegic techniques, in terms of neurological protection.

Renal dysfunction after myocardial revascularization.

OBJECTIVES: In this study, we evaluate the incidence of and analyse the pre and intraoperative risk factors for the development of postoperative renal dysfunction (PRD), and the impact of such an event on perioperative mortality and on hospital length of stay. In addition, we sought to investigate the influence of a mildly increased serum creatinine (1.3-2.0 mg/dl) on perioperative mortality and morbidity. METHODS: The study included 2445 consecutive patients who had no pre-existing renal disease (creatinine or=2.1 mg/dl with a preoperative-to-postoperative increase >or=0.9 mg/dl. Univariate and multivariate analyses were performed where appropriate. RESULTS: Global 30-day mortality was 0.7%. The incidence of PRD was 5.6% (136 patients). Mortality for patients who experienced PRD was 8.8 vs. 0.1% for patients who did not (P<0.001). PRD increased the length of hospital stay by 3.4 days (7.6 vs. 11.0 days; P<0.001), and patients who needed haemodialysis (11%) had a perioperative mortality of 33.3% and a mean hospital length of stay of 16 days. Multivariable logistic regression identified the following variables as independent predictors of PRD: age (P=0.017; odds ratio (OR) 1.3 per 10 years), angina class III/IV (P=0.003; OR 1.7); cardiopulmonary bypass time (P=0.007; OR 1.01 per minute); preoperative serum creatinine levels: group 1 (1.3-1.6 mg/dl (P<0.001; OR 5.5)) and group 2 (1.7-2.0 mg/dl (P<0.001; OR 14.2)). Finally, a mild elevation of the preoperative creatinine level (1.3-2.0 mg/dl) increased significantly the probability of perioperative mortality, low cardiac output, haemodialysis and prolonged hospital stay. CONCLUSIONS: Although the likelihood of PRD in patients without pre-existing renal dysfunction is relatively low, it dramatically increases mortality, morbidity and length of stay after CABG. Mildly elevated (>1.2 mg/dl) preoperative serum creatinine level significantly increases the perioperative mortality and morbidity.

Staged carotid and coronary surgery for concomitant carotid and coronary artery disease.

OBJECTIVE: To demonstrate that staged, consecutive, carotid endarterectomy (CEA) and coronary artery bypass grafting (CABG) are safe, perhaps preferable, alternative for the treatment of patients with severe carotid and coronary artery disease. METHODS: During an 8-year period ending December 1999, 77 (2.1%) of 3633 consecutive patients who were referred for isolated coronary surgery were found to have significant carotid disease and underwent CEA, and subsequently, CABG. The mean age was 65.2 +/- 5.9 years and 66 (85.7%) were males. The majority (84.4%) had triple vessel and 19.4% had left main disease. Carotid disease was unilateral in 71 patients (92.2%) and bilateral in six (7.8%), and 57 (74.0%) were neurologically asymptomatic. Only obstructions >70% were considered for endarterectomy. RESULTS: Eighty-three isolated CEAs were performed with direct clamping of the artery (mean 20.1 +/- 5.9 min) in all but one. There were no deaths. There were two strokes (2.4%) and three (3.6%) myocardial infarctions (MI). The mean admission time was 6.0 +/- 3.5 days. The staging interval was 32.4 days. During coronary surgery, a mean of 2.9 coronary grafts/patient was performed and all but one patient received at least one IMA graft. One patient (1.3%) died. There were two cases (2.6%) of MI and three patients (3.9%) had a stroke. Hence, the overall rates of perioperative mortality, MI and stroke were 1.3, 6.3 and 6.3%, respectively. The mean admission time was 8.3 +/- 6.0 days. CONCLUSIONS: Staging of carotid and coronary operations resulted in low global perioperative mortality and morbidity rates in these high-risk patients and is a good alternative therapeutic option.

Endothelium-dependent vasoactivity of the human internal mammary artery.

Coronary artery disease is recognized as a major health problem worldwide, particularly because of the associated morbidity and mortality. Coronary artery bypass grafting has been an established mainstay in the treatment of this disease for almost half a century and is arguably the most intensively studied surgical procedure ever undertaken. Because of its unique properties, the human internal mammary artery has long been considered the best graft to use in this type of surgery. Previous studies have shown several advantages of this graft compared with others, that is, lower incidence of atherosclerosis. However, few comparative studies on the reactivity of this artery have been published. Moreover, these studies usually focus on isolated cardiovascular risk factors rather than combined risk factors. In fact, patients who require coronary revascularization usually present multiple risk factors, which can interfere with several pathways of regulation of vascular function, namely endothelial function. Several diseases and cardiovascular risk factors have been shown to interfere with endothelial function, promoting the production of vasoconstrictors, inhibiting the production of vasodilators, or both, and thus eventually leading to endothelial dysfunction. Therefore, it is of great interest to study the endothelial function, particularly of the human internal mammary artery, in the presence of combined cardiovascular risk factors and concomitant diseases. Many techniques have been developed to assess the endothelial function, in particular, studies on isolated arteries, as well as spectroscopic, electrochemical, and immunological methods, among others.