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Background and Aims: Uncertainty exists over whether multiple arterial grafting has a sex-related association with survival after coronary artery bypass grafting. This study aims to compare the long-term survival of using multiple arterial grafting vs. single arterial grafting in women and men undergoing coronary artery bypass grafting., Methods: The retrospective study used the Australian and New Zealand Society of Cardiothoracic Surgical Database with linkage to the National Death Index. Patients from 2001 to 2020 were identified. Sex-stratified, inverse probability weighted Cox proportional hazard model was used to facilitate survival comparisons. The primary outcome was all-cause mortality., Results: A total number of 54 275 adult patients receiving at least two grafts in primary isolated bypass operations were analysed. The entire study cohort consisted of 10 693 (19.7%) female patients and 29 711 (54.7%) multiple arterial grafting procedures. At a median (interquartile range) postoperative follow-up of 4.9 (2.3-8.4) years, mortality was significantly lower in male patients undergoing multiarterial than single arterial procedures (adjusted hazard ratio 0.82; 95% confidence interval 0.77-0.87; P < .001). The survival benefit was also significant for females (adjusted hazard ratio 0.83; 95% confidence interval 0.76-0.91; P < .001) at a median (interquartile range) follow-up of 5.2 (2.4-8.7) years. The interaction model from Cox regression suggested insignificant subgroup effect from sex (P = .08) on the observed survival advantage. The survival benefits associated with multiple arterial grafting were consistent across all sex-stratified subgroups except for female patients with left main coronary disease., Conclusions: Compared to single arterial grafting, multiple arterial revascularization is associated with improved long-term survival for women as well as men., (© The Author(s) 2024. Published by Oxford University Press on behalf of the European Society of Cardiology. All rights reserved. For commercial re-use, please contact reprints@oup.com for reprints and translation rights for reprints. All other permissions can be obtained through our RightsLink service via the Permissions link on the article page on our site—for further information please contact journals.permissions@oup.com.)

Background and Aim: The biological behaviour of coronary graft conduits over time may be considered by serial angiography., Methods: A single institution retrospective cohort received mostly clinically indicated angiography between 1997 and 2020, following coronary bypass surgery. Only perfectly patent grafts (absence of any lumen irregularity) for each conduit type at the first postoperative angiogram were selected for a later comparison. The latest angiograms were at least 5 years postoperatively, and at least 1 year after first postoperative angiogram. Analysis was done according to each graft (anastomosis). Comparisons used generalised estimating equations, adjusted for binary logistic regression., Results: Of 143 patients, there were 410 of 468 (87.6%) perfectly patent grafts at the first angiogram, analysed at 6.8±4.0 years postoperative, of which 157 were internal mammary arteries, 228 were radial arteries, and 25 were saphenous veins. At the latest angiogram (12.2±3.8 years postoperative), comparison with the first angiogram for each individual graft found preserved perfect patency for internal mammary arteries, 156 of 157 (99.4%), and for radial arteries, 227 of 228 (99.6%) but saphenous veins deteriorated considerably, 13 of 25 (52.0%). The two arterial grafts (internal mammary and radial) were superior to vein grafts (odds ratio 163; 95% confidence interval [CI] 22-1,211; p<0.001), but not different from each other (odds ratio 0.95; 95% CI 0.78-1.16; p=0.584)., Conclusions: From a position of known angiographic perfect patency post-CABG, internal mammary artery and radial artery grafts retained their perfect patency in the longer term, but saphenous vein grafts did not., Competing Interests: Conflicts of Interest None declared., (Copyright © 2024 The Authors. Published by Elsevier B.V. All rights reserved.)

Background: It is unknown if the presence of saphenous vein grafting (SVG) adversely affects late survival following coronary surgery with multiple arterial grafting (MAG) versus single arterial grafting., Methods and Results: A retrospective, observational, multicenter cohort study from 2001 to 2020 was conducted using the Australian and New Zealand Society of Cardiac and Thoracic Surgeons Database linked to the National Death Index. Patients undergoing primary isolated coronary artery bypass grafting with ≥2 grafts were included, and exclusions were patients aged <18 years, reoperations, concomitant or previous cardiac surgery, and the absence of arterial grafting. Demographics, comorbidities, medication, and operative configurations were propensity score matched between cohorts. The primary outcome was all-cause late death. Of 59 689 eligible patients, 35 113 were MAG (58.8%), and 24 576 were single arterial grafting (41.2%). Of the MAG cohort, 17 055 (48.6%) patients did not receive supplementary SVG (total arterial revascularization). Matching separately generated 22 764 patient pairs for MAG versus single arterial grafting, and 11 137 patient pairs for MAG with total arterial revascularization versus MAG with ≥1 supplementary vein grafts. At a median follow-up duration of 5.0 years postoperatively, the mortality rate was significantly lower for MAG than single arterial grafting (hazard ratio [HR], 0.79 [95% CI, 0.76-0.83]; P <0.001). The stratified MAG analysis found that MAG with total arterial revascularization had a lower risk of late death (HR, 0.85 [95% CI, 0.80-0.91]; P <0.001) compared with MAG with ≥1 supplementary vein grafts. Sensitivity analyses produced consistent outcomes as the primary analysis. Following adjustment for the presence of SVG in the Cox model, the survival advantage of incremental number of arteries was lost., Conclusions: Multiple arterial grafting has significantly improved long-term survival compared with single arterial grafting. A further incremental survival benefit exists when no SVG is used.

Approximately 95% of patients of any age undergoing contemporary, coronary bypass surgery will receive at least 1 saphenous vein graft (SVG). It is recognized that SVG will develop progressive and accelerated atherosclerosis, resulting in a stenosis, and in occlusion that occurs in 50% by 10 years postoperatively. For arterial conduits, there is little evidence of progressive failure as for SVG. Could avoidance of SVG (total arterial revascularization [TAR]) lead to a different late (>5 year) survival? A literature review of 23 studies (N = 100,314 matched patients) at a mean 8.8 years postoperative found reduced all-cause mortality for TAR (HR: 0.77; 95% CI: 0.71-0.84; P < 0.001). An expanded analysis with a new unpublished data set (N = 63,288 matched patients) was combined with the literature review (N = 127,565). It found reduced all-cause mortality for TAR (HR: 0.78; 95% CI: 0.72-0.85; P < 0.001). Additional Bayesian analysis found a very high probability of a TAR-associated reduction all-cause mortality., Competing Interests: Funding Support and Author Disclosures The authors have reported that they have no relationships relevant to the contents of this paper to disclose., (Crown Copyright © 2022. Published by Elsevier Inc. All rights reserved.)

Background: Where each patient has all three conduits of internal mammary artery (IMA), saphenous vein graft (SVG) and radial artery (RA), most confounders affecting comparison between conduits can be mitigated. Additionally, since SVG progressively fails over time, restricting patient angiography to the late period only can mitigate against early SVG patency that may have occluded in the late period., Methods: Research protocol driven conventional angiography was performed for patients with at least one of each conduit of IMA, RA and SVG and a minimum of 7 years postoperative. The primary analysis was perfect patency and secondary analysis was overall patency including angiographic evidence of conduit lumen irregularity from conduit atheroma. Multivariable generalized linear mixed model (GLMM) was used. Patency excluded occluded or "string sign" conduits. Perfect patency was present in patent grafts if there was no lumen irregularity., Results: Fifty patients underwent coronary angiography at overall duration postoperative 13.1 ± 2.9, and age 74.3 ± 7.0 years. Of 196 anastomoses, IMA 62, RA 77 and SVG 57. Most IMA were to the left anterior descending territory and most RA and SVG were to the circumflex and right coronary territories. Perfect patency RA 92.2% was not different to IMA 96.8%, P = 0.309; and both were significantly better than SVG 17.5%, P < 0.001. Patency RA 93.5% was also not different to IMA 96.8%, P = 0.169, and both arterial conduits were significantly higher than SVG 82.5%, P = 0.029. Grafting according to coronary territory was not significant for perfect patency, P = 0.997 and patency P = 0.289. Coronary stenosis predicted perfect patency for RA only, P = 0.030 and for patency, RA, P = 0.007, and SVG, P = 0.032. When both arterial conduits were combined, perfect patency, P < 0.001, and patency, P = 0.017, were superior to SVG., Conclusions: All but one patent internal mammary artery or radial artery grafts had perfect patency and had superior perfect patency and overall patency compared to saphenous vein grafts.

Objectives: Saphenous vein graft (SVG) remains the predominant conduit used in coronary surgery. The internal mammary artery has higher later term patency and confers superior survival. Current debate focuses on the increased use of arterial conduits rather than eradication of venous conduits., Methods: Patient data extracted from the Australian and New Zealand Society of Cardiothoracic Surgeons database from 2001-2013 were linked to the national death registry held by the Australian Institute of Health and Welfare for all-cause mortality with censor date 7 October 2014. The dataset was divided according to use of SVG rather than the arterial conduit. Analyses of SVG ≥ 1 or SVG = 1 were compared to SVG = 0. Additionally, groups of 3, 4 or 5 grafts were subjected to multiple analyses testing the mortality hazard with increasing use of SVG. Propensity score matched analyses were conducted using 24 variables., Results: Of 51 113 primary coronary surgery patients, unmatched survival at up to 12.5 years was significantly lower for SVG ≥ 1, n = 33 359, mortality hazard ratio (HR) 1.24 [95% confidence interval (CI) 1.18-1.30], P < 0.001; and for SVG = 1, mortality HR 1.19 (95% CI 1.12-1.26), P < 0.001. Similar results were present for the propensity score matched groups; SVG ≥ 1, n = 14 355 pairs, HR 1.22 (95% CI 1.15-1.30), P < 0.001; and for SVG = 1, n = 12 316 pairs, HR 1.22 (95% CI 1.14-1.30), P < 0.001. All matched analyses within restricted graft groups had increasing HR with increased number of SVG used., Conclusions: Any use of SVGs is independently associated with reduced survival after coronary artery bypass surgery.

Objective: There is initial evidence that the use of volatile anesthetics can reduce the postoperative release of cardiac troponin I, the need for inotropic support, and the number of patients requiring prolonged hospitalization following coronary artery bypass graft (CABG) surgery. Nevertheless, small randomized controlled trials have failed to demonstrate a survival advantage. Thus, whether volatile anesthetics improve the postoperative outcome of cardiac surgical patients remains uncertain. An adequately powered randomized controlled trial appears desirable., Design: Single blinded, international, multicenter randomized controlled trial with 1:1 allocation ratio., Setting: Tertiary and University hospitals., Interventions: Patients (n=10,600) undergoing coronary artery bypass graft will be randomized to receive either volatile anesthetic as part of the anesthetic plan, or total intravenous anesthesia., Measurements and Main Results: The primary end point of the study will be one-year mortality (any cause). Secondary endpoints will be 30-day mortality; 30-day death or non-fatal myocardial infarction (composite endpoint); cardiac mortality at 30day and at one year; incidence of hospital re-admission during the one year follow-up period and duration of intensive care unit, and hospital stay. The sample size is based on the hypothesis that volatile anesthetics will reduce 1-year unadjusted mortality from 3% to 2%, using a two-sided alpha error of 0.05, and a power of 0.9., Conclusions: The trial will determine whether the simple intervention of adding a volatile anesthetic, an intervention that can be implemented by all anesthesiologists, can improve one-year survival in patients undergoing coronary artery bypass graft surgery., (Copyright © 2017 Elsevier Inc. All rights reserved.)

PL-arginine cardioplegia decreases biochemical markers of myocardial damage and oxidative stress in patients with normal left ventricular function. We investigated the effects of L-arginine supplemented cardioplegic arrest in patients with reduced ejection fraction. Fifty-three adult patients with left ventricular ejection fraction <35% undergoing elective coronary artery bypass surgery were randomised to receive blood cardioplegia with or without L-arginine. Following cardiopulmonary bypass, measured endpoints were cardiac troponin-I concentration at 12 and 24 hours, coronary sinus concentrations of malondialdehyde and superoxide dismutase activity at five and 15 minutes, lactic acid flux at one, five and 15 minutes and left ventricular systolic and diastolic function after protamine administration. There were no differences in cardiac troponin-I between groups. Malondialdehyde was lower in the L-arginine group, 0.28 ± 0.12 vs 0.48 ± 0.32 (5 minutes) and 0.31 ± 0.14 vs 0.38 ± 0.15 nmol.ml(-1) (15 minutes) (P=0.0004). Superoxide dismutase activity was higher in L-arginine group, 229 ± 87 vs 191.3 ± 68 (5 minutes), 229 ± 54 vs 198 ± 15 nmol.minute(-1).m(l) (15 minutes) (P=0.005). Lactic acid flux was lower in L-arginine group, 0.15 ± 0.23 vs 0.48 ± 0.32 (1 minute), 0.08 ± 0.19 vs 0.38 ± 0.31 (5 minutes) and -0.15 ± 0.13 vs 0.26 ± 0.30 mmol.l(-1) (15 minutes), (P=0.0003). There was no difference in left ventricular systolic function. The mitral annular tissue Doppler inflow (e') velocity during early diastole improved in the L-arginine group following cardiopulmonary bypass (control 4.2 ± 1.9 cm.s(-1) to 3.6 ± 1.2 cm.s(-1) vs L-arginine 3.8 ±1.2 cm.s(-1) to 4.6 ± 1.4 cm.s(-1)) (P=0.018). In patients with reduced ejection fraction, L-arginine supplemented cardioplegic arrest did not affect postoperative cardiac troponin-I levels, but attenuated cardiac cellular peroxidation and improved early left ventricular diastolic function.

We investigated the influence of either propofol or desflurane on the incidence of postoperative cognitive dysfunction in a randomised trial of 180 patients undergoing coronary artery bypass surgery. The primary outcome was incidence of postoperative cognitive dysfunction at 3 months, defined as ≥1 SD deterioration in two or more of 12 neurocognitive tests. Secondary outcomes included early postoperative cognitive dysfunction (between days three and seven), delirium on day one, morbidity and length of hospital stay. Early postoperative cognitive dysfunction was significantly higher with propofol compared with desflurane (56/84 (67.5%) vs 41/83 (49.4%), respectively, p=0.018), but this effect was not seen at 3 months (10/87 (11.2%) vs 9/90 (10.0%), respectively. There was no difference in delirium (7/89 (7.9%) vs 12/91 (13.2%), respectively, length of hospital stay (median (IQR [range]) 7 (6-9 [4-15]) vs 6 (5-7 [5-16) days, respectively or other morbidities. Desflurane was associated with reduced early cognitive dysfunction., (© 2011 The Authors. Anaesthesia © 2011 The Association of Anaesthetists of Great Britain and Ireland.)

The assessment of diastolic function using trans-mitral Doppler and tissue Doppler imaging during coronary artery bypass surgery (CABG) is complex, with anaesthesia, blood loss and ischaemia all contributing to altered loading conditions. Ten patients undergoing coronary artery bypass grafting underwent simultaneous transoesophageal and pressure volume loop analysis of diastolic function at different loading conditions (baseline, preload reduction, afterload increase, increased heart rate and post cardiopulmonary bypass). The mean age was 59±9 years and 3 (range 2-5) grafts. Altered loading conditions resulted in no significant changes in Tau or the end diastolic pressure volume relationship. dP/dtmin varied significantly across loading conditions (p<0.001). Tissue Doppler peak Em measured at the lateral mitral annulus was affected significantly with increased heart rate (p<0.01), but was insensitive to changes in preload and afterload. Instantaneous end diastolic stiffness (IEDS=log(10)PCWP/EDA) did not alter during loading conditions (p=0.99). Peak Em (lateral annulus) and IEDS appear promising as measures of diastolic function over a range of haemodynamic alterations, although changes in Peak Em may not reflect diastolic function accurately if the heart rate substantially changes., (Copyright © 2011 Australasian Society of Cardiac and Thoracic Surgeons and the Cardiac Society of Australia and New Zealand. All rights reserved.)

Transoesophageal echocardiography measures of systolic left ventricular function obtained during coronary artery bypass surgery are heavily influenced by alterations in loading conditions. No validation of these measurements against load independent indices obtained by pressure-volume loop analysis has been undertaken in humans. Ten patients undergoing coronary artery bypass surgery underwent simultaneous transoesophageal echocardiography and pressure-volume loop analysis of cardiac function at different loading conditions (reduced preload, increased afterload and atrial pacing). Fractional area change, afterload corrected fractional area change, and lateral basal wall peak systolic myocardial velocity, along with dP/dt, were compared to the preload recruitable stroke work relationship. There were no significant differences between the echocardiography measures when compared to the preload recruitable stroke work relationship; however, dP/dt varied significantly across loading conditions (p<0.001). Transoesophageal echocardiography adequately assesses systolic function across loading conditions commonly seen during coronary artery bypass surgery.

Background: High thoracic epidural analgesia (HTEA) has been shown to reduce psychological morbidity in the early period following coronary artery bypass graft surgery (CABG). Our aim was to identify whether the effect persists in the longer term., Materials and Methods: Patients from a previous randomised study of HTEA for CABG were followed up 6 months to 3 years following surgery. The cardiac depression scale (CDS) was used to identify severity of depression., Results: Sixty-one of the original 78 patients were able to participate in the study. Eight point three percent of patients had CDS scores >100, consistent with severe depression (1 epidural patient, 4 control patients, P=0.353). After adjustment for time of follow-up, the CDS scores in patients who received HTEA were significantly lower (66+/-3.5) than patients who received intravenous morphine analgesia (79+/-3.5) P<0.05, Conclusion: The use of HTEA results in a lower risk of depression 6 months or more following CABG.

Alfentanil and propofol total intravenous anaesthesia was assessed in 25 patients undergoing coronary artery bypass graft surgery with cardiopulmonary bypass (CPB). A manually controlled alfentanil infusion, calculated from estimated lean body mass and published pharmacokinetic data, was effective in achieving target plasma concentrations, while the "Diprifusor" system was used to vary propofol target concentrations according to changes in haemodynamics and anaesthetic requirement. The effects of CPB on alfentanil plasma concentrations were offset by changes in protein binding and free-fraction of the drug. With the use of only two target plasma concentrations for alfentanil (changed after CPB), a pre-determined infusion profile ensured effective plasma concentrations during surgery and concentrations unlikely to inhibit extubation within six hours of sternal closure.

Background: Postoperative pain may be severe after coronary artery bypass surgery. High thoracic epidural analgesia (HTEA) provides intense analgesia., Methods: Eighty patients were randomized to HTEA or intravenous morphine analgesia (control). Patients received coronary artery bypass surgery (CABG) with cardiopulmonary bypass. Pain was measured by visual analogue scale 0 to 10. Psychologic morbidity, intraoperative hemodynamics, ventricular function, lung function, and physiotherapy cooperation were also assessed. On the third postoperative day HTEA and morphine were ceased and only oral medications were used. Acetaminophen, indomethacin, and tramadol were allowed as supplemental analgesics in both groups., Results: The primary endpoint of pain scores was significantly less with HTEA on postoperative days 1 and 2 at rest, 0.02 +/- 0.2 versus 0.8 +/- 1.8 (p = 0.008) and 0.1 +/- 0.4 versus 1.2 +/- 2.7 (p = 0.022), respectively, and with coughing 1.2 +/- 1.7 versus 4.4 +/- 3.1 (p < 0.001) and 1.5 +/- 2.0 versus 3.6 +/- 3.1 (p = 0.001), respectively. When HTEA and morphine were ceased on day 3, there were no significant differences. The secondary endpoints of postoperative depression (p = 0.033) and posttraumatic stress subscales (p = 0.021) of the Minnesota Multiphasic Personality Inventory were lower with HTEA. Extubation occurred earlier with HTEA, 2.6 versus 5.4 hours (p < 0.001). HTEA showed improved physiotherapy cooperation (p < 0.001), arterial oxygen tension (p = 0.041), and peak expiratory flow rate (p = 0.001). Mean arterial pressure was lower with HTEA (p = 0.036), otherwise there were no differences in intraoperative hemodynamics or ventricular function., Conclusions: Epidural analgesia reduces pain after coronary operation and is associated with improved physiotherapy cooperation, earlier extubation, and reduced risk of depression and posttraumatic stress.

We aimed to assess whether movement of the interatrial septum predicts change in pulmonary capillary wedge pressure (PCWP). In 71 patients undergoing cardiac surgery, the interatrial septum was categorised by its shape and movement using transesophageal echocardiography. Fixed curvature (FC) was identified by bowing of the interatrial septum from left to right throughout the cardiac cycle, mid-systolic reversal (MSR) by minimal septal movement and transient reversal (right to left) during mid-systole, and mid-systolic buckling (MSB) by marked movement and buckling of the septum during mid-systole. These were compared with PCWP. Sensitivity and interobserver reliability was studied with continuous PCWP and TEE measurement during a period of acute volume alteration in 10 additional patients. Interatrial septal movement predicted PCWP, with mean PCWP (95% confidence intervals) for FC, 18.1 mmHg (16.7 to 19.6), MSR 13.2 mmHg (12.5 to 13.8) and MSB, 9.9 mmHg (9.0 to 10.7) mmHg. The mean PCWP at which a change in pattern occurred was 8.9 mmHg (8.3 to 9.6) for MSR to MSB, and 10.9 mmHg (10.1 to 11.8) for MSR to FC (p<0.001). There was no significant difference in mean values for all three observers. Movement of the interatrial septum predicts change in PCWP.

Background: To examine the effect of screening the aorta for atheroma before aortic manipulation and use of exclusive Y graft revascularization on the incidence of neuropsychological dysfunction after coronary artery bypass., Methods: Aortic atheroma was detected using epiaortic and transesophageal echocardiography. Atheroma avoidance was facilitated by use of the exclusive Y graft technique, which has no aortic coronary anastomoses. In the control group aortic atheroma was assessed by manual palpation, and we attempted to avoid any atheroma detected. In this group we also used aorta-coronary grafts. Transcranial Doppler imaging of the right middle cerebral artery was used to detect cerebral microemboli. Neuropsychological dysfunction was defined as a 20% or more decline in score for at least 20% of a neuropsychometric battery of ten tests for each patient., Results: Late dysfunction at 57 +/- 2 days postoperatively in the control group was 38.1% and in the echo/Y group was 3.8% (p' = 0.012). Microemboli detected by transcranial Doppler imaging during periods of aortic manipulation was greater for those with late dysfunction (5.2 +/- 3.0 compared with 0.5 +/- 0.2) (p' = 0.018). No clinical strokes occurred in either group., Conclusions: The combined techniques of epiaortic screening and exclusive Y graft for coronary artery bypass operations resulted in a low incidence of late neuropsychological dysfunction.

Objective: To determine left ventricular end-diastolic area (EDA) and pulmonary vein and mitral inflow Doppler velocities in patients undergoing coronary artery bypass graft (CABG) surgery using transesophageal echocardiography (TEE). To examine the effects of age, sex, and left ventricular function on these values., Design: Prospective observational study; all measurements performed before cardiopulmonary bypass., Setting: Tertiary referral teaching hospital., Participants: Eighty-six elective CABG surgery patients., Interventions: Intraoperative TEE was performed in all patients., Measurements and Main Results: The left ventricular EDA was measured at the midpapillary level, excluding the papillary muscles. Mean EDA for patients with normal left ventricular function, defined by fractional area change (FAC) 0.50 or greater, was 10.66 cm2 and when indexed to body surface area was 5.6 cm2/m2. The EDA was greater in patients with impaired left ventricular function (FAC < 0.50). Mean EDA was 14.84 cm2, and EDA/body surface area was 7.8 cm2/m2. In patients with FAC 0.50 or greater, mean peak pulmonary vein Doppler velocities were 46.10 cm/sec (systole), 31.71 cm/sec (diastole), and 1.50 (ratio systole to diastole). Mean peak mitral inflow Doppler velocities were 57.25 cm/sec (early diastole), 57.21 cm/sec (late diastole), and 1.10 (ratio early to late), and deceleration time was 216 msec. Age, sex, and left ventricular function were not significant predictors of Doppler variables., Conclusions: Values are presented for a predominantly white population undergoing cardiac surgery. Left ventricular dysfunction is associated with increased left ventricular EDA measurements.

Objective: To compare radial artery (RA) patency with internal mammary artery (IMA) patency for coronary artery bypass surgery in our early experience., Methods: Symptomatic as well as asymptomatic patients with > or =1 RA coronary graft underwent postoperative angiography. Each anastomosis was considered separately. A string sign referred to a diffusely narrowed conduit, which did not fill the grafted coronary artery, as well as all occluded conduits. The raw value of P was adjusted for the testing of multiple hypotheses (P'). The patency data for each conduit was divided into two parts. 'Cut-off' stenosis for a conduit was the lowest dividing coronary stenosis at which a difference in patency rate with P< or =0.05 occurred., Results: One-hundred-and-twenty-nine patients had 137 radial arteries and 157 angiograms. Only the most recent angiogram was analyzed for each patient at 13+/-0.7 months (n=129). Overall patency for arterial conduit 91% (n=404) was not different from venous conduit 91% (n=42) and patency for RA 90% (n=226) was not different from IMA 92% (n=178), (P'=0.999). Cut-off stenosis for RA was 70% and IMA was 40%. Patent arterial conduit had a mean coronary stenosis of 85% and non-patent conduit 64%, (P'<0.001). Right coronary territory patency was 82 vs. 94% for other territories (P'=0.022). No overall differences in patency were noted for patients with sequential anastomoses, symptoms or coronary disease at the anastomosis at the time of surgery. Reversible ischaemia was detected in the distribution of only two of 14 string signs in patients undergoing sestamibi exercise protocol following angiogram., Conclusion: There were no differences in patency between radial artery and internal mammary artery at 13 months post-operative. Lower coronary stenosis and right coronary territory predicted lower patency. The clinical importance of a string sign remains to be determined.

Objective: To determine if arterial conduit selection or more efficient arterial revascularization techniques influence in-hospital mortality., Methods: Data from patients undergoing coronary artery bypass surgery at Royal Melbourne Hospital, Australia, between 1 January 1996 and 30 June 1998 (n = 1681) was collected prospectively. Logistic regression analysis was performed., Results: Independent preoperative predictors of increased in-hospital mortality included renal failure, redo coronary artery surgery and intra-aortic balloon pump use. In-hospital mortality for total arterial revascularization 0.7%, radial artery use 0.9%, pedicled arterial revascularization 0.2%, composite arterial conduit 0.4%, and the exclusive Y graft operation 0.3%. These were all associated with reduced in-hospital mortality. Mortality when vein graft was used was 2.9%. Most patients received total arterial revascularization, which was considered the primary surgical strategy., Conclusion: Total arterial revascularization, radial artery use and complex arterial reconstructions were associated with reduced in-hospital mortality. Preoperative renal failure, intra-aortic balloon pump use and redo coronary surgery predicted greater in-hospital mortality.

Background: Total arterial coronary revascularization can be achieved by joining arteries together as a composite graft with the proximal left internal mammary artery as the only source of blood inflow. Proof of the capacity of this composite conduit to provide adequate blood flow to the coronary circulation is required., Methods: The radial artery was anastomosed to the left internal mammary artery as a Y graft in 17 patients and all coronary arteries grafted. Intraoperative blood flow through the composite grafts was evaluated by the transit-time Doppler technique., Results: Against no resistance, blood flow in the left internal mammary artery alone was 99 +/- 9 mL/min and rose to 173 +/- 16 mL/min when the radial artery was anastomosed as a Y graft. Composite-graft flow following grafting was 88 +/- 9 mL/min, 49 +/- 6 mL/min when the aortic clamp was removed and native coronary flow restored and 82 +/- 13 mL/min following weaning from cardiopulmonary bypass. The maximal potential flow through the composite graft was 2.3-fold (95% CI 1.6 to 3.2) greater than that after cardiopulmonary bypass., Conclusions: Total arterial revascularization, using a composite graft, provided a 2.3-fold reserve of blood flow to the coronary vascular bed through the grafts.

Background: The pedicled (in-situ) left internal mammary artery grafted to the left anterior descending artery has a very high late patency and reduces late mortality following coronary artery bypass surgery. A technique is described which achieves total arterial revascularization in patients with multivessel coronary disease and which is also entirely pedicled., Methods: Using the left internal mammary artery and radial artery joined as a composite Y graft, all coronary territories may be grafted., Results: One in-hospital death from 464 patients (0.2%) occurred. Age (mean +/- standard error) was 64.7 +/- 0.5 years and number of distal anastomoses 3.4 +/- 0.04. Of 1,681 patients from Royal Melbourne Hospital, 346 had this operation. Comparison found no preoperative selection bias and no postoperative differences in complications. Actuarial survival was 0.98 +/- 0.01 at 36.1 +/- 0.3 months., Conclusions: Total arterial revascularization may be performed using the left internal mammary artery and radial artery as a composite Y graft. There was no increase in complications. This technique preserves the left internal mammary artery to left anterior descending artery graft.

Objective: To develop a simple harvest technique for radial artery (RA). To investigate the morbidity and functional outcome of RA harvest., Methods: The neurovascular fascia surrounding the RA is divided. Only loose areolar tissue surrounds this artery making harvest of RA simple and allowing minimal trauma to the RA and surrounding muscles. Topical and intraluminal vasodilators but no systemic vasodilators are used., Results: RA harvest commenced in December 1994. Between 1996 and 30 June 1998, 2167 RA were harvested and used to construct 3105 coronary anastomoses. A dramatic rise in RA use occurred during 1996. More than 80% of patients undergoing coronary artery bypass surgery (CABG) have RA harvested since this time. Total arterial revascularization rate also rose dramatically and is currently 80% of all CABG. This rate has been assisted by a rapid rise in the use of composite arterial grafting where aortic anastomoses can be avoided and currently represents 40% of all CABG. Hand strength was tested in 328 non-selected patients and was not reduced by RA harvest when hand dominance was taken into account. Objective sensation loss was present in 0.3% for the superficial radial nerve and 2.1% for the lateral cutaneous nerve of forearm. Pulse oximetry observations detected statistically significant but clinically irrelevant differences. Scar hypersensitivity occurred in 20%. Only two patients of all patients undergoing RA harvest reported late hand ischaemia., Conclusions: Harvest of the RA within the neurovascular plane is simple and associated with low morbidity.

A new classification is described to improve precision of thoracic atheroma reporting. In 68 patients, the thoracic aorta was screened with epiaortic and transesophageal echocardiography. The thoracic aorta is divided into 6 zones corresponding to sites of aortic manipulation. Zones 1-3, proximal, mid and distal ascending aorta, Zones 4-5, proximal and distal arch and Zone 6, proximal descending aorta. Each zone is further sub-divided into anterior, left lateral, posterior and right lateral quadrants. There is a marked increase in moderate and severe atheroma between Zones 1-3 and Zone 4-6 (p<0. 001). There is a difference in atheroma by quadrant with the anterior the most frequent. (p<0.001) Once the grade and location of atheroma was classified, a comparison of the estimation of risk of dislodging atheroma during three surgical methods for care, was performed. Of 50 quadrants of atheroma, the composite arterial pedicle Y graft CABG would manipulate 5, Aortocoronary CABG with single aorta cross clamp, 16, and Aortocoronary CABG with aortic partial occlusion clamp, 21. This classification of 6 zones and 4 quadrants within each zone will increase the precision of atheroma reporting and allow better comparison of stroke reduction interventions.

Levosimendan is emerging as a novel cardioprotective inotrope. Levosimendan augments myocardial contractility by sensitising contractile myofilaments to calcium without increasing myosin adenosine triphosphatase activity or oxygen consumption. Levosimendan activates cellular adenosine triphosphate-dependent potassium channels, a mechanism which is postulated to protect cells from ischaemia in a manner similar to ischaemic preconditioning. Levosimendan may therefore protect the ischaemic myocardium during ischaemia-reperfusion as well as improve the contractile function of the heart. Adenosine triphosphate-dependent potassium channel activation by levosimendan may also be protective in other tissues, such as coronary vascular endothelium, kidney and brain. Clinical trials in patients with decompensated heart failure and myocardial ischaemia show levosimendan to improve haemodynamic performance and potentially improve survival. This paper reviews the known pharmacology of levosimendan, the clinical experience with the drug to date and the potential use of levosimendan as a cardioprotective agent during surgery. [ABSTRACT FROM AUTHOR]