Predictors of postoperative atrial fibrillation in patients with coronary artery disease undergoing cardiopulmonary bypass: a possible role for myocardial ischemia and atrial inflammation.

OBJECTIVE: To evaluate the preoperative presence of C-reactive protein (CRP) and troponin T(hs-TnT) in patients with coronary artery disease (CAD) undergoing cardiopulmonary bypass (CPB) in order to better clarify the role of atrial inflammation and/or myocardial ischemia in the development of postoperative atrial fibrillation (POAF). DESIGN: Prospective, nonrandomized study. SETTING: University hospital. PARTICIPANTS: Thirty-eight consecutive ischemic patients admitted to the authors' hospital for CAD undergoing elective on-pump coronary artery bypass grafting (CABG). INTERVENTION: Elective on-pump CABG. MEASUREMENTS AND MAIN RESULTS: Peripheral blood samples were collected from all patients before and 24 hours after CABG to assess high sensitive (hs)-CRP and troponin T (hs-TnT) levels. The patients' heart rhythm was monitored by continuous ECG telemetry. Biopsies from the right atrial appendage were obtained at the beginning of the CABG procedure in order to perform immunohistochemistry for CRP and reverse transcription polymerase chain reaction for CRP mRNA expression. Fourteen patients out of 38 (36%) developed POAF. Atrial CRP was found in 31 patients (82%), 10 with POAF and 21 with sinus rhythm (71% v 87% respectively, p = ns). None of the atrial samples was positive for CRP mRNA. Atrial CRP did not correlate with serum hs-CRP levels and with occurrence of POAF, but with the incidence of diabetes (p = 0.010). Postoperative hs-TnT levels, but not hs-CRP levels, were identified as the only predictor of POAF occurrence (p = 0.016). CONCLUSIONS: In patients undergoing CABG, neither peripheral nor tissue preoperative CRP levels, but only postoperative hs-TnT levels, correlated with POAF, suggesting the primary role of an ischemic trigger of atrial fibrillation.

Restricted T-Cell Repertoire in the Epicardial Adipose Tissue of Non-ST Segment Elevation Myocardial Infarction Patients.

Aims: Human epicardial adipose tissue, a dynamic source of multiple bioactive factors, holds a close functional and anatomic relationship with the epicardial coronary arteries and communicates with the coronary artery wall through paracrine and vasocrine secretions. We explored the hypothesis that T-cell recruitment into epicardial adipose tissue (EAT) in patients with non-ST segment elevation myocardial infarction (NSTEMI) could be part of a specific antigen-driven response implicated in acute coronary syndrome onset and progression. Methods and Results: We enrolled 32 NSTEMI patients and 34 chronic coronary syndrome (CCS) patients undergoing coronary artery bypass grafting (CABG) and 12 mitral valve disease (MVD) patients undergoing surgery. We performed EAT proteome profiling on pooled specimens from three NSTEMI and three CCS patients. We performed T-cell receptor (TCR) spectratyping and CDR3 sequencing in EAT and peripheral blood mononuclear cells of 29 NSTEMI, 31 CCS, and 12 MVD patients. We then used computational modeling studies to predict interactions of the TCR beta chain variable region (TRBV) and explore sequence alignments. The EAT proteome profiling displayed a higher content of pro-inflammatory molecules (CD31, CHI3L1, CRP, EMPRINN, ENG, IL-17, IL-33, MMP-9, MPO, NGAL, RBP-4, RETN, VDB) in NSTEMI as compared to CCS (P < 0.0001). CDR3-beta spectratyping showed a TRBV21 enrichment in EAT of NSTEMI (12/29 patients; 41%) as compared with CCS (1/31 patients; 3%) and MVD (none) (ANOVA for trend P < 0.001). Of note, 11/12 (92%) NSTEMI patients with TRBV21 perturbation were at their first manifestation of ACS. Four patients with the first event shared a distinctive TRBV21-CDR3 sequence of 178 bp length and 2/4 were carriers of the human leukocyte antigen (HLA)-A*03:01 allele. A 3D analysis predicted the most likely epitope able to bind HLA-A3*01 and interact with the TRBV21-CDR3 sequence of 178 bp length, while the alignment results were consistent with microbial DNA sequences. Conclusions: Our study revealed a unique immune signature of the epicardial adipose tissue, which led to a 3D modeling of the TCRBV/peptide/HLA-A3 complex, in acute coronary syndrome patients at their first event, paving the way for epitope-driven therapeutic strategies.

Assessment of the position of retrograde cardioplegia catheter: comparison of hemodynamic versus manual evaluation in a prospective randomized trial.

OBJECTIVE: To evaluate a hemodynamic method for the assessment of the position of the retrograde cardioplegia catheter (RCC) versus conventional Manual Assessment. METHODS: We randomized 200 patients undergoing aortic valve surgery to Manual (n = 101) or Hemodynamic Assessment (n = 99). In the Hemodynamic group a 25% pressure increase at the tip of the RCC when a fistula with the ascending aorta was created via a luer-lock was considered indicative of correct RCC placement. Transesophageal echocardiography was used as a comparison evaluation method. RESULTS: The Hemodynamic and Manual Assessment considered the RCC positioning successful in 89.9% versus 85.1% of cases. Echocardiography confirmed these results in Hemodynamic group but revealed 23 cases of misrecognized incorrect placement in the Manual group (p < 0.0001). Manual maneuvers resulted in 18 cases of secondary displacement and 19 cases of hemodynamic instability (p < 0.0001). CONCLUSIONS: The Hemodynamic Method is quantitative, reproducible, highly reliable, and safer than palpation in the posterior atrioventricular groove.

Systematic bilateral internal mammary artery grafting: lessons learned from the CATHolic University EXtensive BIMA Grafting Study.

OBJECTIVES: Despite claims of feasibility, to date no study has examined the effect of systematic bilateral internal mammary artery (BIMA) use in a large cohort of real-world unselected patients. The CATHolic University EXtensive BIMA Grafting Study (CATHEXIS) registry was designed to assess the feasibility and safety of systematic BIMA grafting. METHODS: The CATHEXIS was a single-centre, prospective, observational, propensity-matched study. The study was supposed to include 2 arms of 500 patients each: a prospective arm and a retrospective arm. The prospective arm included almost all patients referred for coronary artery bypass grafting (CABG) at our institution after the start of the CATHEXIS with very few exceptions. BIMA would have been used in all these patients. The retrospective arm included patients submitted to CABG before the start of the CATHEXIS and propensity matched to the prospective group (average BIMA use 50%; the radial artery was extensively used). Safety analyses were scheduled after enrolment of 200, 300 and 400 BIMA patients. RESULTS: After the first 226 patients, the BIMA use percentage was 88.5% (200 of 226). In 178 (89%) patients, mammary arteries were used as Y graft. Postoperative mortality was 2%, and incidence of perioperative myocardial infarction, graft failure and sternal complications were 3.5%, 3% and 5.5%, respectively. No perioperative stroke occurred. The incidence of major adverse cardiac events (particularly graft failure and sternal complications) in the BIMA arm were significantly higher than those in the propensity-matched cohort; the study was stopped for safety. CONCLUSIONS: In a real world setting the systematic use of BIMA was associated with a higher incidence of perioperative adverse events (particularly sternal complications). Individualization of the revascularization strategy and use of alternative arterial conduits are probably preferable to systematic use of BIMA.

Myocardial apoptosis predicts postoperative course after aortic valve replacement in patients with severe left ventricular hypertrophy.

BACKGROUND AND AIM OF THE STUDY: Myocardial apoptosis has been implicated in heart failure and post-infarct remodeling. In some patients with severe aortic stenosis, delayed valvular replacement is associated with a poor in-hospital outcome. The study aim was to evaluate the impact of cardiomyocyte apoptosis on the postoperative course after aortic valve replacement (AVR) for severe aortic stenosis. METHODS: During elective AVR, myocardial biopsies were obtained from the left ventricle of 11 patients with severe left ventricular hypertrophy (LVH), and the samples analyzed for apoptosis. RESULTS: The mean apoptotic rate was 10.4 +/- 3.7 per thousand. (range: 5-16 per thousand). The apoptotic rate correlated directly with preoperative NYHA functional class, duration of intensive care unit (ICU) stay, number of days of postoperative acute renal insufficiency, and serum level of troponin T at 24 h; the apoptotic rate correlated inversely with cardiac index at 24 h postoperatively. At multivariate analysis, the apoptotic rate and left ventricular mass index were independent predictors of prolonged ICU stay. The apoptotic rate and duration of cardiopulmonary bypass were predictive of the duration of postoperative acute renal insufficiency. CONCLUSION: The study results showed an association between myocardial apoptosis and postoperative outcome in patients with severe LVH submitted for AVR. Non-invasive correlates of apoptosis may be introduced as a means of identifying patients at a higher operative risk, and may help in the evaluation of asymptomatic patients with severe aortic stenosis. Anti-apoptotic strategies before and during surgery would possibly ameliorate the surgical results.

Prosthetic valve endocarditis: predictors of early outcome of surgical therapy. A multicentric study.

OBJECTIVES: Prosthetic valve endocarditis (PVE) is an uncommon yet dreadful complication in patients with prosthetic valves that requires a distinct analysis from native valve endocarditis. The present study aims to investigate independent risk factors for early surgical outcomes in patients with PVE. METHODS: A retrospective cohort study was conducted in 8 Italian Cardiac Surgery Units from January 2000 to December 2013 by enrolling all PVE patients undergoing surgical treatment. RESULTS: A total of 209 consecutive patients were included in the study. During the study period, the global rate of surgical procedures for PVE among all operations for isolated or associated valvular disease was 0.45%. Despite its rarity this percentage increased significantly during the second time frame (2007-2013) in comparison with the previous one (2000-2006): 0.58% vs 0.31% (P < 0.001). Intraoperative and in-hospital mortality rates were 4.3% and 21.5%, respectively. Logistic regression analysis identified the following factors associated with in-hospital mortality: female gender [odds ratio (OR) = 4.62; P < 0.001], shock status (OR = 3.29; P = 0.02), previous surgical procedures within 3 months from the treatment (OR = 3.57; P = 0.009), multivalvular involvement (OR = 8.04; P = 0.003), abscess (OR = 2.48; P = 0.03) and urgent surgery (OR = 6.63; P < 0.001). CONCLUSIONS: Despite its rarity, PVE showed a significant increase over time. Up to now, in-hospital mortality after surgical treatment still remains high (>20%). Critical clinical presentation and extension of anatomical lesions are strong preoperative predictors for poor early outcome.

Epicardial adipose tissue microbial colonization and inflammasome activation in acute coronary syndrome.

BACKGROUND: Epicardial adipose tissue (EAT) has a close functional and anatomic relationship with epicardial coronary arteries. Accumulating evidence suggests that host microbiome alterations may play a role in several inflammatory/immune disorders, triggering a robust proinflammatory response also involving interleukin-1ß (IL-1ß) and the NALP3 inflammasome. In the current study, we explore the hypothesis that in patients with non-ST elevation acute coronary syndrome (ACS), EAT contains potentially pro-atherosclerotic bacteria that might elicit inflammasome activation. METHODS: EAT samples were obtained during coronary artery bypass grafting from ACS (n=18) and effort stable angina (SA; n=16) patients, and as controls, from patients with angiographically normal coronary arteries undergoing surgery for mitral insufficiency (MVD; n=13). In all patients, NALP3 and proIL-1ß mRNA expressions were evaluated with qRT-PCR. In 3 patients from each group, EAT microbiota composition was determined using next-generation sequencing technologies. RESULTS: In EAT, mRNA expression of both NALP3 and pro-IL1ß was significantly higher in ACS than in SA and MVD (P=0.028 and P=0.005, respectively). A broad range of bacterial species (n=76) was identified in both ACS and SA, with different predominant species. In contrast, microbial DNA was barely observed in MVD. CONCLUSIONS: Our study demonstrated the presence of bacterial DNA directly into EAT, surrounding diseased coronary arteries, of patients with ACS. Furthermore, ACS is associated with NALP3/inflammasome pathway activation in EAT. Our data suggest that the EAT environment is susceptible to microbial colonization that might stimulate a proinflammatory response. These findings add new elements to the pathogenesis of ACS and suggest novel therapeutic targets.

Implantation in coronary circulation induces morphofunctional transformation of radial grafts from muscular to elastomuscular.

BACKGROUND: The purpose of this research was to investigate the in vivo morphofunctional changes induced in the radial artery (RA) by its use as coronary artery bypass conduit by comparing the morphological features and vasoreactivity of the native RA versus the coronary RA graft in the same patient. METHODS AND RESULTS: Ten years after surgery, 10 patients were submitted to intravascular ultrasound examination of the RA graft of the controlateral (in situ) RA and of the internal thoracic artery (ITA) graft and to vasoactive challenges with acetylcholine and serotonin. Quantitative angiographic assessment showed that the mean diameter of the RA coronary grafts was significantly larger than that of the in situ RA and of the ITA (2.89+/-0.40 mm RA grafts, 2.14+/-0.52 mm in situ RA, 2.25+/-0.53 mm ITA grafts; P<0.001). The in situ RA demonstrated a typical muscular architecture, whereas RA coronary grafts showed a clear reduction of the thickness of the medial layer and had a less well-defined muscular component of the media with interposition of elastic tissue. Serotonin endovascular infusion elicited a strong spastic reaction in in situ RAs; the same challenge induced only moderate constriction in RA and ITA coronary grafts. CONCLUSIONS: Implantation in the coronary circulation leads to major anatomic and vasoreactive modifications of the RAs that tend to lose the morphofunctional features of a muscular conduit and assume those of an elastomuscular artery, such as the ITA.

Ten-year Echo-Doppler evaluation of forearm circulation following radial artery removal for coronary artery bypass grafting.

OBJECTIVE: To investigate the chronic consequences of radial artery removal for coronary artery bypass surgery on the forearm circulation. METHODS: Thirty-nine patients submitted to radial artery removal for coronary artery bypass were submitted to serial Echo-Doppler evaluation of the flow and morphology of the forearm arteries until 10 years follow-up. RESULTS: The peak systolic velocity of the ulnar artery of the operated side was significantly higher than the control site. The intima-media thickness of the ulnar artery was always significantly higher on the operated side, and this difference reached statistical significance at 10 years follow-up. There was a significantly higher prevalence of atherosclerotic plaques in the ulnar artery (UA) of the operated versus control arm (11/39 vs 0/39; p=0.005). CONCLUSIONS: Radial artery removal for coronary artery bypass surgery leads to a chronic increase in ulnar flow accompanied by increased intima-media thickness and accelerated atherosclerotic disease. These findings may have potentially important implications for surgical indications and patients management.

Radial Artery as a Coronary Artery Bypass Conduit: 20-Year Results.

BACKGROUND: There is a lack of evidence for the choice of the second conduit in coronary surgery. The radial artery (RA) is a possible option, but few data on very-long-term outcomes exist. OBJECTIVES: This study describes 20-year results of RA grafts used for coronary artery bypass grafting and the effects of RA removal on forearm circulation. METHODS: We report the results of the prospective 20-year follow-up of the first 100 consecutive patients who received the RA as a coronary bypass conduit at our institution. RESULTS: Follow-up was 100% complete. There were 64 deaths, 23 (35.9%) from cardiovascular causes. Kaplan-Meier 20-year survival was 31%. Of the 36 survivors, 33 (91.6%) underwent RA graft control at a mean of 19.0 ± 2.5 years after surgery. The RA was found to be patent in 24 cases (84.8% patency). In the overall population, probability of graft failure at 20 years was 19.0 ± 0.2% for the left internal thoracic artery (ITA), 25.0 ± 0.2% for the RA, and 55.0 ± 0.2% for the saphenous vein (p = 0.002 for RA vs. saphenous vein, 0.11 for RA vs. ITA, and p < 0.001 for ITA vs. saphenous vein). Target vessel stenosis >90%, but not location of distal anastomosis, significantly influenced long-term RA graft patency. No patients reported hand or forearm symptoms. The ulnar artery diameter was increased in the operated arm (2.44 ± 0.43 mm vs. 2.01 ± 0.47 mm; p < 0.05) and correlated with the peak systolic velocity of the second palmar digital artery (Pearson coefficient: 0.621; p < 0.05). CONCLUSIONS: The 20-year patency rate of RA grafts is good, and not inferior to the ITA, especially when the conduit is used to graft a vessel with >90% stenosis. RA harvesting does not lead to hand or forearm symptoms, even at a very-long-term follow-up.

Long-term results of the radial artery used for myocardial revascularization.

BACKGROUND: No information is available on the long-term results of radial artery (RA) grafts used as coronary artery bypass conduits. METHODS AND RESULTS: In this report, we describe the long-term (105+/-9 months) angiographic results of a series of 90 consecutive patients in whom the RA was used as a coronary artery bypass conduit directly anastomosed to the ascending aorta. The long-term patency and perfect patency rates of the RA were 91.6% and 88%, respectively, versus 97.5% and 96.3% for internal thoracic artery grafts. The severity of stenosis of the target vessel clearly influenced long-term RA patency, whereas location of the target vessel and long-term use of calcium channel blockers did not influence angiographic results. Preserved endothelial function and absence of flow-limiting, fibrous, intimal hyperplasia were also documented. CONCLUSIONS: Ten years after surgery, RA grafts have excellent patency and perfect patency rates. Appropriate surgical technique and correct indication are the key factors for long-term RA patency.

Late reoperations after acute aortic dissection repair: Single-center experience.

BACKGROUND: After repair of acute type A aortic dissection, aortic complications can develop, and reoperations might be necessary. In our retrospective study, we wanted to assess early and late outcomes in this cohort of patients. METHODS: From September 2005 to July 2012, 21 consecutive patients previously operated on for acute type A aortic dissection underwent 27 redo aortic surgical procedures. Indications for redo procedures were: enlargement of the false lumen in the residual aorta (18 events), severe aortic regurgitation with or without aortic root dilatation (8 events), suture dehiscence and pseudoaneurysm at the proximal or distal aortic graft anastomosis (5 events) or at the coronary button anastomosis in patients who previously underwent a Bentall procedure (1 patient). In all cases, total or partial cardiopulmonary bypass was used. Hypothermic cardiocirculatory arrest was needed in 22 (81%) procedures. RESULTS: Hospital mortality was 3.7% (1/27), reexploration for bleeding and paraplegia rates were 7.4% and 7.4%, respectively. Marfan patients received 3.2 procedures per patient vs. 1.5 in non-Marfan patients (p < 0.01). At a mean follow-up of 6.5 years, 2 aortic events occurred: 1 aortic death, and 1 additional aortic redo surgery. CONCLUSIONS: When procedures are carried out on elective basis, redo aortic surgery can be performed in all segments of the aorta with good early and late outcomes. Close lifelong clinical and radiological follow-up is mandatory. After repair of acute type A aortic dissection, Marfan patients are more prone to develop late complications, with a more rapid evolution.

Effect of surgical revascularization of a right coronary artery tributary of an infarcted nonischemic territory on the outcome of patients with three-vessel disease: a prospective randomized trial.

BACKGROUND: We evaluated the in-hospital and long-term effects of surgical grafting of a dominant graftable right coronary artery tributary of an infarcted nonischemic territory in patients with triple-vessel disease who were undergoing coronary artery bypass grafting. METHODS: Of 303 consecutive patients undergoing coronary artery bypass grafting with 3-vessel coronary disease and a dominant right coronary artery tributary of an infarcted nonischemic territory, 154 were randomized to right coronary artery revascularization and 149 to no right coronary artery grafting. In all cases, standard on-pump surgical myocardial revascularization was performed. RESULTS: Overall hospital mortality was 2 of 154 versus 1 of 149 (P =.97); no difference in in-hospital outcome was observed between the 2 groups. At follow-up, cardiac event-free survival was 84 of 152 in the right coronary artery grafting series and 62 of 148 in the non-right coronary artery grafting group (P =.20). However, when the analysis was limited to surviving patients without new scintigraphic evidence of ischemia (to avoid confounding factors derived from ischemia in the left coronary system or right coronary artery graft malfunction), we found that patients who received a right coronary artery graft had fewer cardiac events, a lower incidence of arrhythmia, and less left ventricular dilatation than did the non-right coronary artery revascularized series. CONCLUSIONS: Surgical grafting of a right coronary artery tributary of an infarcted nonischemic territory in patients with 3-vessel coronary artery disease submitted to coronary artery bypass grafting improved late electric stability, ventricular geometry, and event-free survival but did not affect in-hospital or 10-year survival.

Early vasoreactive profile of skeletonized versus pedicled internal thoracic artery grafts.

BACKGROUND: No data are available on the early vasoreactive profile of skeletonized internal thoracic artery grafts. METHODS: Fifteen patients undergoing primary isolated coronary artery bypass grafting were randomly assigned to receive a skeletonized or pedicled internal thoracic artery graft. On the second postoperative day all patients were subjected to follow-up angiography and endovascular infusion of serotonin, acetylcholine, and isosorbide dinitrate. RESULTS: Internal thoracic artery grafts were widely patent in all cases. Mean diameters of the internal thoracic artery were 1.95 +/- 0.17 mm in the pedicled group and 2.26 +/- 0.40 mm in the skeletonized group. After serotonin challenge, mean internal thoracic artery diameters were reduced to 1.44 +/- 0.34 mm and 1.64 +/- 0.14 mm, respectively; acetylcholine challenge lead to a moderate degree of vasoconstriction (1.55 +/- 0.59 mm in the pedicled group and 1.84 +/- 0.15 mm in the skeletonized group). No statistically significant difference was evident between the two groups at any step. CONCLUSION: Skeletonization does not affect the early vasoreactive profile of internal thoracic artery grafts used for surgical myocardial revascularization.

Normothermia does not improve postoperative hemostasis nor does it reduce inflammatory activation in patients undergoing primary isolated coronary artery bypass.

BACKGROUND: Despite its common acceptance in clinical practice, the effective benefits of normothermic systemic perfusion during coronary artery bypass operations are far from established. METHODS: A total of 113 patients undergoing primary isolated coronary artery bypass were randomly assigned to normothermic (37 degrees C) or hypothermic (26 degrees C) systemic perfusion. The clinical course of the patients was prospectively recorded, and several inflammatory and fibrinolytic markers (C-reactive protein, fibrinogen, interleukin 6, plasminogen activator inhibitor 1, prothrombin time, activated partial thromboplastin time, platelets, and white blood cell counts) were determined before surgical intervention; 24, 48, and 72 hours thereafter; and at hospital discharge. RESULTS: Postoperatively, 2 in-hospital deaths occurred in the normothermic series and none in the hypothermic series. Four patients had a myocardial infarction, 1 had respiratory insufficiency, 1 had to be reoperated on for graft malfunction, and none had renal insufficiency in the hypothermic group versus 1 patient with each of these complications in the normothermic series. Mean blood loss in the first 24 hours was 766 +/- 223 mL in the normothermic group and 740 +/- 220 mL in the hypothermic group. None of these differences was statistically significant. Similarly, no significant difference in the postoperative level of any of the measured variables at any time point was evident between the patients in the normothermic and hypothermic groups. CONCLUSION: Normothermic systemic perfusion does not influence the clinical course or the extent of inflammatory and hemostatic activation in patients undergoing primary isolated coronary artery bypass.

Genetic control of postoperative systemic inflammatory reaction and pulmonary and renal complications after coronary artery surgery.

BACKGROUND: Although some data suggest that the individual genetic predisposition for developing major or minor degrees of postoperative systemic inflammatory reaction may influence postoperative morbidity, this hypothesis has not been clinically tested to date. Methods and results The -174 G/C polymorphism of the promoter of the interleukin 6 gene was determined preoperatively in 111 consecutive patients submitted to primary isolated coronary artery bypass. The results of the genetic analysis were then correlated with the postoperative interleukin 6 levels and the development of postoperative renal and pulmonary complications. G homozygotes had significantly higher interleukin 6 levels postoperatively (P <.0001 for the difference between areas under the curve). These patients also had worse postoperative pulmonary and renal function. The mean perioperative difference in serum creatinine, potassium, and nitrogen was 0.82 +/- 0.34, 0.99 +/- 0.44, and 10.1 +/- 7.8 mg/dL versus 0.18 +/- 0.14, 0.15 +/- 0.48, and 2.6 +/- 4.1 mg/dL for GG versus non-GG carriers (P <.0001), respectively. The mean respiratory index at 6 and 12 hours was 2.9 +/- 0.8 and 2.8 +/- 0.3 versus 2.1 +/- 0.5 and 1.3 +/- 0.1, respectively (P <.0001). The mean duration of mechanical ventilation was 22.5 +/- 2.1 versus 12.7 +/- 6.7 hours (P <.01). A correlation was found between postoperative interleukin 6 levels and renal and pulmonary complications. CONCLUSION: The interleukin 6 -174 G/C polymorphism modulates postoperative interleukin 6 levels and is associated with the degree of postoperative renal and pulmonary dysfunction and in-hospital stay after coronary surgery.

Skeletonization does not influence internal thoracic artery innervation.

BACKGROUND: This study was designed to compare the effect of surgical harvesting on internal thoracic artery innervation and to assess the eventual presence of denervation supersensitivity in skeletonized grafts. METHODS: Nineteen patients who underwent primary isolated coronary artery bypass grafting were randomly assigned to receive a skeletonized (n = 9) or pedicled (n = 10) internal thoracic artery graft. Immunohistochemical nerve localization using anti-S-100 protein, anti-160-kd neurofilament polypeptide and anti-tyrosine hydroxylase antibodies was performed on distal specimens of arteries to study vascular innervation. Moreover, endovascular vasoactive challenges using serotonin and methylergometrine were performed at early angiographic control to evaluate the eventual presence of denervation supersensitivity. RESULTS: Quantitative analysis of immunohistochemical specimens revealed lack of difference in the number of positive cells between skeletonized and pedicled arteries for all the antibodies used. No difference in the reaction to serotonin and methylergometrine was found between skeletonized and pedicled arteries. CONCLUSIONS: Skeletonization does not influence internal thoracic artery innervation.

High risk coronary artery bypass patient: incidence, surgical strategies, and results.

BACKGROUND: To describe our experience in the treatment of high risk coronary artery bypass patients and compare patients assigned to on-pump or off-pump surgery. METHODS: During a 42-month period 306 high risk (Euroscore > 5) coronary artery bypass patients were consecutively treated at our institution. On the basis of the coronary anatomy and possibility of achieving a complete revascularization, 197 patients were assigned to off-pump and 109 to on-pump operation. Overall mortality was 6.2% (19 of 306 patients). RESULTS: Although patients treated off-pump had a better cardiac status, no clinical advantages related to the avoidance of cardiopulmonary bypass were found in the overall population. Off-pump patients had more early and late cardiac complications, whereas patients operated on-pump exhibited an higher incidence of postoperative systemic organ dysfunction. Off-pump surgery improved in-hospital outcome only in the subset of patients at highest risk. CONCLUSIONS: Avoidance of cardiopulmonary bypass does not confer significant clinical advantages in all high risk coronary patients; instead, there are particular subsets of patients in whom beating heart surgery can be particularly indicated and others for whom on-pump revascularization appears a better solution. Adaptation of the operation to the single patient is probably the way to improve outcome.

Coronary artery bypass grafting in type II diabetic patients: a comparison between insulin-dependent and non-insulin-dependent patients at short- and mid-term follow-up.

BACKGROUND: Diabetes is a well-established risk factor for coronary artery disease, and it is associated with an increased rate of early and late adverse events after myocardial revascularization by coronary artery bypass grafting. METHODS: A prospective follow-up study was done to evaluate the short-term and mid-term outcomes of type II diabetic patients who had coronary artery bypass grafting at our institution between 1996 and May 1999. A total of 200 patients, 100 insulin-dependent diabetic patients (group I) and 100 non-insulin-dependent diabetic patients (group II), met the inclusion criteria of the study and were included in the clinical follow-up study. RESULTS: The characteristics of the patients of the two groups were similar for baseline clinical angiographic and operative characteristics. In particular, no significant differences in cardiopulmonary bypass and aortic cross-clamping times were noted between the two groups. The number grafts per patient was similar between the two groups. There were no in-hospital deaths, but postoperative complications were different among the two series. In fact, 33% of patients in group I had at least one major complication compared with 20% in group II (p = 0.037). The cumulative number of complications was 148 in group I and 69 in group II, and the mean number of complications per patient was 4.5 and 3.5 in groups I and II, respectively. The major differences in perioperative complication rates were found in the need for prolonged (> 24 hours) ventilation, occurrence of respiratory or renal insufficiency, and mediastinitis. The mean length of stay in the intensive care unit and for total hospitalization were longer in group I than group II (4.3 +/- 2.8 days versus 2.8 +/- 2.7 days [p = 0.010] and 11.1 +/- 2.2 days versus 7.2 +/- 2.4 group II [p < 0.05], respectively). At long-term follow-up, group I patients had a significantly higher mortality rate (29% versus 10%, p < 0.001). Moreover, overall late cardiac and noncardiac complication rates were significantly higher in group I than II (37% versus 22%, p = 0.02). In the multivariate analysis including several preoperative and operative variables, treatment by insulin, advanced age (> 75 years), left ventricular dysfunction (left ventricular ejection fraction < 35%), and complex lesions at coronary angiography (American Heart Association lesion classification type C lesion) were found as independent predictors of increased mortality. CONCLUSIONS: Our data show that patients with insulin-dependent type II diabetes who had coronary artery bypass grafting have a significantly higher rate of major postoperative complications with an extremely unfavorable short- and long-term prognosis. Diabetic patients on insulin treatment should be considered high-risk candidates for coronary artery bypass grafting and require intense perioperative and long-term monitoring. Further studies will be necessary to investigate whether such conclusions may be appropriate for newer surgical strategies such as off-pump operation.