Comparative analysis of the patency of the internal thoracic artery in the CABG of left anterior descending artery: 6-month postoperative coronary CT angiography evaluation

Objective

To assess the patency of the pedicled right internal thoracic artery with an anteroaortic course and compare it to the patency of the left internal thoracic artery , in anastomosis to the left anterior descending artery in coronary artery bypass grafting by using coronary CT angiography at 6 months postoperatively.

Methods

Between December 2008 and December 2011, 100 patients were selected to undergo a prospective coronary artery bypass grafting procedure without cardiopulmonary bypass. The patients were randomly divided by a computer-generated list into Group-1 (G-1) and Group-2 (G-2), comprising 50 patients each, the technique used was known at the beginning of the surgery. In G-1, coronary artery bypass grafting was performed using the left internal thoracic artery for the left anterior descending and the free right internal thoracic artery for the circumflex, and in G-2, coronary artery bypass grafting was performed using the right internal thoracic artery pedicled to the left anterior descending and the left internal thoracic artery pedicled to the circumflex territory.

Results

The groups were similar with regard to the preoperative clinical data. A male predominance of 75.6% and 88% was observed in G-1 and G-2, respectively. Five patients migrated from G-1 to G-2 because of atheromatous disease in the ascending aorta. The average number of distal anastomoses was 3.48 (SD=0.72) in G-1 and 3.20 (SD=0.76) in G-2. Coronary CT angiography in 96 re-evaluated patients showed that all ITAs, right or left, used in situ for the left anterior descending were patent. There were no deaths in either group.

Conclusion

Coronary artery bypass grafting surgery involving anastomosis of the anteroaortic right internal thoracic artery to the left anterior descending artery has an outcome similar to that obtained using the left internal thoracic artery for the same coronary site.     

New technique Right Anterior Small Thoracotomy (RAST operation) for beating heart grafting of the right internal thoracic artery to the posterior descending artery to the posterior descending artery in a third redo CABG patient. A novel coronary technique

Third REDO-CABG is a challenge for the surgical team. Usually a patent mammary is theonly graft working and the sternotomy becomes a risky procedure. Injury to a patentgraft has been associated to a high mortality rate. Many different approaches havebeen proposed. We describe a novel technique to approach the right coronary arterythrough a right anterior small thoracotomy using the right mammary prolonged withsaphenous vein for grafting the posterior descending artery on the beating heart. Thetechnique is very simple and feasible because anatomically the right coronary arteryand the right mammary are very close and the mobilization of the heart isminimal.     

Oxidative stress in coronary artery bypass surgery

Objective

The aim of this prospective study was to assess the dynamics of oxidative stress during coronary artery bypass surgery with cardiopulmonary bypass.

Methods

Sixteen patients undergoing coronary artery bypass grafting were enrolled. Blood samples were collected from the systemic circulation during anesthesia induction (radial artery - A1), the systemic venous return (B1 and B2) four minutes after removal of the aortic cross-clamping, of the coronary sinus (CS1 and CS2) four minutes after removal of the aortic cross-clamping and the systemic circulation four minutes after completion of cardiopulmonary bypass (radial artery - A2). The marker of oxidative stress, malondialdehyde, was measured using spectrophotometry.

Results

The mean values of malondialdehyde were (ng/dl): A1 (265.1), B1 (490.0), CS1 (527.0), B2 (599.6), CS2 (685.0) and A2 (527.2). Comparisons between A1/B1, A1/CS1, A1/B2, A1/CS2, A1/A2 were significant, with ascending values (P<0.05). Comparisons between the measurements of the coronary sinus and venous reservoir after the two moments of reperfusion (B1/B2 and CS1/CS2) were higher when CS2 (P<0.05). Despite higher values ​​after the end of cardiopulmonary bypass (A2), when compared to samples of anesthesia (A1), those show a downward trend when compared to the samples of the second moment of reperfusion (CS2) (P<0.05).

Conclusion

The measurement of malondialdehyde shows that coronary artery bypass grafting with cardiopulmonary bypass is accompanied by increase of free radicals and this trend gradually decreases after its completion. Aortic clamping exacerbates oxidative stress but has sharper decline after reperfusion when compared to systemic metabolism. The behavior of thiobarbituric acid species indicates that oxidative stress is an inevitable pathophysiological component.     

地尔硫(艹卓)在非体外循环下冠状动脉搭桥术围术期的心肌保护作用

目的 探讨非体外循环下冠状动脉搭桥术(OPCABG)围术期输注地尔硫(艹卓)对心肌的保护作用.方法 40例择期手术患者,随机分为地尔硫(艹卓)组(D组)与硝酸甘油组(C组),每组20例.D组静脉给予地尔硫(艹卓)0.1 mg·kg-1·h-1至术后24 h,C组常规给予硝酸甘油0.1μg·kg-1·h-1至术后24 h.分别在术毕、术后1、3、6、12和24 h记录血流动力学参数,并采集血样测定血清肌钙蛋白Ⅰ(cTnI).结果 与C组比较,D组的心率术后1、3、6、12、24 h均较慢(P＜0.05).C组房颤4例,D组1例;C组室上性心动过速5例,D组1例.术后6 h的cTnI,D组显著低于C组(P＜0.05).结论 OPCABG围术期持续输注地尔硫(艹卓)有比硝酸甘油更好的抗缺血和抗心律失常的保护作用.     

Atrioventricular block in coronary artery bypass surgery: perioperative predictors and impact on mortality

Introduction

Disturbances of the cardiac conduction system are frequent in the postoperative period of coronary artery bypass surgery. They are mostly reversible and associated with some injury of the conduction tissue, caused by the ischemic heart disease itself or by perioperative factors.

Objective

Primary: investigate the association between perioperative factors and the emergence of atrioventricular block in the postoperative period of coronary artery bypass surgery. Secondary: determine the need for temporary pacing and of a permanent pacemaker in the postoperative period of coronary artery bypass surgery and the impact on hospital stay and hospital mortality.

Methods

Analysis of a retrospective cohort of patients submitted to coronary artery bypass surgery from the database of the Postoperative Heart Surgery Unit of the Sao Lucas Hospital of the Pontifical Catholic University of Rio Grande do Sul, using the logistic regression method.

Results

In the period from January 1996 to December 2012, 3532 coronary artery bypass surgery were carried out. Two hundred and eighty-eight (8.15% of the total sample) patients had atrioventricular block during the postoperative period of coronary artery bypass surgery, requiring temporary pacing. Eight of those who had atrioventricular block progressed to implantation of a permanent pacemaker (0.23% of the total sample). Multivariate analysis revealed a significant association of atrioventricular block with age above 60 years (OR=2.34; CI 95% 1.75-3.12; P<0.0001), female gender (OR=1.37; CI 95% 1.06-1.77; P=0.015), chronic kidney disease (OR=2.05; CI 95% 1.49-2.81; P<0.0001), atrial fibrillation (OR=2.06; CI 95% 1.16-3.66; P=0.014), functional class III and IV of the New York Heart Association (OR=1.43; CI 95% 1.03-1.98; P=0.031), perioperative acute myocardial infarction (OR=1.70; CI 95% 1.26-2.29; P<0.0001) and with the use of the intra-aortic balloon in the postoperative period of coronary artery bypass surgery (OR=1.92; CI 95% 1.21-3.05; P=0.006). The presence of atrioventricular block resulted in a significant increase in mortality (17.9% vs. 7.3% in those who did not develop atrioventricular block) (OR=2.09; CI 95% 1.46-2.99; P<0.0001) and a longer hospital stay (12.75 days x 10.53 days for those who didn''t develop atrioventricular block) (OR=1.01; CI 95% 1.00-1.02; P=0.01).

Conclusions

In most cases, atrioventricular block in the postoperative period of coronary artery bypass surgery is transient and associated with several perioperative factors: age above 60 years, female sex, chronic kidney disease, atrial fibrillation, New York Heart Association functional class III or IV, perioperative acute myocardial infarction and use of an intra-aortic balloon. Its occurrence prolongs hospitalization and, above all, doubles the risk of mortality.     

The effect of gender on the early results of coronary artery bypass surgery in the younger patients' group

Introduction

In this retrospective study, we aimed to determine the risk factors for coronary artery bypass surgery in patients under 45 years of age, and evaluate the early postoperative results and the effect of gender.

Methods

A total of 324 patients under 45 years of age who undergone on-pump coronary artery bypass surgery between April 12, 2004 and January 10, 2012 were included to the study. Patients divided into groups as follows: Group 1 consisted of 269 males (mean age 41.3), Group 2 consisted of 55 females (mean age 41.6). Preoperative risk factors, intraoperative and postoperative data and early mortality rates of the groups were compared.

Results

Smoking rate was significantly higher in Group 1. Diabetes mellitus incidence and body mass index were significantly higher in Group 2 (P values P=0.01; P=0.0001; P=0.04 respectively). The aortic cross-clamping and cardiopulmonary bypass time and number of grafts per patient were significantly higher in Group 1 (P values P=0.04; P=0.04; P=0.002 respectively). There were no deaths in either group.

Conclusion

We found that gender has no effect on early mortality rates of the coronary bypass surgery patients under 45 years.     

Cardiopulmonary bypass increases the risk of vasoplegic syndrome after coronary artery bypass grafting in patients with dialysis-dependent chronic renal failure

Objective

Coronary artery bypass grafting is currently the best treatment for dialysis patients with multivessel coronary artery involvement. Vasoplegic syndrome of inflammatory etiology constitutes an important postoperative complication, with highly negative impact on prognosis. Considering that these patients have an intrinsic inflammatory response exacerbation, our goal was to evaluate the incidence and mortality of vasoplegic syndrome after myocardial revascularization in this group.

Methods

A retrospective, single-center study of 50 consecutive and non-selected dialysis patients who underwent myocardial revascularization in a tertiary university hospital, from 2007 to 2012. The patients were divided into 2 groups, according to the use of cardiopulmonary bypass or not (off-pump coronary artery bypass). The incidence and mortality of vasoplegic syndrome were analyzed. The subgroup of vasoplegic patients was studied separately.

Results

There were no preoperative demographic differences between the cardiopulmonary bypass (n=20) and off-pump coronary artery bypass (n=30) group. Intraoperative data showed a greater number of distal coronary arteries anastomosis (2.8 vs. 1.8, P<0.0001) and higher transfusion rates (65% vs. 23%, P=0.008) in the cardiopulmonary bypass group. Vasoplegia incidence was statistically higher (P=0.0124) in the cardiopulmonary bypass group (30%) compared to the off-pump coronary artery bypass group (3%). Vasoplegia mortality was 50% in the cardiopulmonary bypass group and 0% in the off-pump coronary artery bypass group. The vasoplegic subgroup analysis showed no statistically significant clinical differences.

Conclusion

Cardiopulmonary bypass increased the risk for developing postoperative vasoplegic syndrome after coronary artery bypass grafting in patients with dialysis-dependent chronic renal failure.     

Relationship between pre-extubation positive endexpiratory pressure and oxygenation after coronary artery bypass grafting

Introduction

After removal of endotracheal tube and artificial ventilation, ventilatory support should be continued, offering oxygen supply to ensure an arterial oxygen saturation close to physiological.

Objective

The aim of this study was to investigate the effects of positive-end expiratory pressure before extubation on the oxygenation indices of patients undergoing coronary artery bypass grafting.

Methods

A randomized clinical trial with seventy-eight patients undergoing coronary artery bypass grafting divided into three groups and ventilated with different positive-end expiratory pressure levels prior to extubation: Group A, 5 cmH₂O (n=32); Group B, 8 cmH₂O (n=26); and Group C, 10 cmH₂O (n=20). Oxygenation index data were obtained from arterial blood gas samples collected at 1, 3, and 6 h after extubation. Patients with chronic pulmonary disease and those who underwent off-pump, emergency, or combined surgeries were excluded. For statistical analysis, we used Shapiro-Wilk, G, Kruskal-Wallis, and analysis of variance tests and set the level of significance at P<0.05.

Results

Groups were homogenous with regard to demographic, clinical, and surgical variables. There were no statistically significant differences between groups in the first 6 h after extubation with regard to oxygenation indices and oxygen therapy utilization.

Conclusion

In this sample of patients undergoing coronary artery bypass grafting, the use of different positive-end expiratory pressure levels before extubation did not affect gas exchange or oxygen therapy utilization in the first 6 h after endotracheal tube removal.     

Nebivolol in preventing atrial fibrillation following coronary surgery in patients over 60 years of age

Objective

Postoperative atrial fibrillation is a common complication after cardiac surgery, with an incidence as high as 20-50%. Increased age is associated with a significant increase in postoperative atrial fibrillation risk. This common complication is associated with higher morbidity and mortality rates. The aim of this study was to assess the efficacy of nebivolol in preventing atrial fibrillation following coronary artery bypass surgery in patients over 60 years of age.

Methods

In this prospective randomized study, 200 patients who were candidates for elective coronary artery bypass surgery were divided into two groups. The first group was administered with nebivolol and the second group was administered with metoprolol. Treatment was initiated four days prior to surgery, and patients were monitored for atrial fibrillation until discharge. Forty-one patients recieved 50 mg metoprolol succinate daily, which was initiated minimum 4 days before surgery.

Results

Demographic data were similar in both groups. The incidence of postoperative atrial fibrillation in both groups was similar, with no significant difference being identified [n=20 (20%); n=18 (18%), P=0.718; respectively]. There were not any mortality at both groups during study. Inotropic agent requirement at ICU was similar for both groups [n=12 (12%), n=18 (18%), P=0.32].

Conclusion

We compared the effectiveness of nebivolol and metoprolol in decreasing the incidence of postoperative atrial fibrillation, and determined that nebivolol was as effective as metoprolol in preventing postoperative atrial fibrillation at patients. Nebivolol may be the drug of choice due to its effects, especially after elective coronary artery bypass surgery.     

Right-sided reverse T composite arterial grafting to complete revascularization of the right coronary artery

Complete arterial revascularization for the right coronary artery is underused mainlydue to technical issues. Herein we report on a new approach for complete arterialrevascularization of arterial revascularization for the right coronary arterybranches. Complete arterial revascularization for the right coronary arteryrevascularization was performed in 8 patients using a reverse T composite arterialgraft. None of the patients suffered perioperative myocardial infarction. Allpatients underwent noninvasive coronary imaging, displaying an early patency rate of100%. Complete arterial arterial revascularization for the right coronary arteryrevascularization using a reverse T graft offers a new paradigm with enhancedtechnical flexibility in performing all arterial myocardial completerevascularizations in selected patients.     

Association of pre and intraoperative variables with postoperative complications in coronary artery bypass graft surgery

Objective

To associate the pre- and intraoperative variables with postoperative complications of patients undergoing coronary artery bypass graft surgery.

Methods

The pre- and intraoperative risk factors of individuals of both genders with diagnosis of coronary insufficiency undergoing coronary artery bypass graft have been studied.

Results

Fifty-eight individuals with median age 62 ± 10 year-old were included in the study, 67% of whom were male. Fourteen (24.1%) patients were smokers, 39 (67.2%) had previous myocardial infarction history, 11 (19%) had undergone coronary angioplasty, 74% had hypertension, 27% had diabetes mellitus, 64% had dyslipidemia and 15.5% had chronic obstructive pulmonary disease. Eighteen (31%) patients presented postoperative complications, most frequent being: infection in surgical incision, difficulties in deambulation, dyspnea, urinary infection and generalized weakness. Male patients had fewer complications than females (P=0.005). Patients with chronic obstructive pulmonary disease remained hospitalized for longer time periods (P=0.019). Postoperative complications occurred in 50% of the patients with creatinine increased, while only 27.1% of the patients with normal value of creatinine had complications (P=0.049). In addition, complications occurred in 50% of the patients with diabetes mellitus, while only 23.8% of patients without diabetes mellitus had complications (P=0.032). The intraoperative factors showed no statistically significant differences.

Conclusion

The preoperative factors are associated with postoperative complications in patients undergoing coronary artery bypass graft surgery.     

同期颈动脉支架术及冠状动脉旁路移植术治疗颈动脉狭窄合并冠心病的疗效分析

目的:探讨同期颈动脉支架术(CAS)及冠状动脉旁路移植术(CABG)治疗颈动脉狭窄合并冠心病的安全性与疗效。方法:回顾性分析中日友好医院2007年1月―2014年12月收治的25例颈动脉狭窄合并冠心病患者资料,其中11例同期行CAS和CABG(同期组),14例分期行CAS和CABG(分期组),比较两组患者的主要临床指标。结果:两组患者术前基本资料具有可比性。所有患者手术均获成功,无围手术期死亡患者。与分期组比较,同期组中位手术时间(250minvs.280min)、中位住院时间(19dvs.24d)明显缩短(均P0.05),中位术中出血量(750m Lvs.600m L)、输血量(1000m Lvs.1200m L)、ICU时间(23hvs.24h)、呼吸机时间(19hvs.16.5h)差异均无统计学意义(P0.05)。同期组出现术后30d内小卒中1例,一过性脑缺血发作(TIA)1例,围手术期肺部感染1例,术后短暂低血压3例;分期组出现TIA2例,术后短暂低血压4例,再次开胸止血1例,围手术期肺部感染1例,两组均无心肌梗死及死亡病例。结论:同期和分期行CAS和CABG治疗颈动脉狭窄合并冠心病均安全有效,同期手术可以缩短手术和住院时间,应根据患者的病变特点选择合适的治疗方法。     

An evaluation of the intraoperative transit time measurements of coronary bypass flow

Objective: The intraoperative measurement of the coronary bypass flow enables the identification of technical errors while the sternum is still open. The transit-time flow method is able to effectively measure the internal thoracic artery graft flow. The aim of the present study was to analyze the factors which affected the bypass flow rate. Methods: We measured the blood flow of 291 in situ internal thoracic artery (ITA) and 190 saphenous vein (SV) grafts constructed in 171 patients undergoing coronary artery bypass grafting from December 1996 to March 2000 using this method during the surgery. All patients underwent postoperative coronary angiography before the patients were discharged. The blood flow rate of all bypass grafts constructed was assessed after the patients were weaned from cardiopulmonary bypass. Results: The mean flow rate of all ITA grafts was 65.1±36.7 ml/min and that of all SV grafts was 56.4±29.9 ml/min. According to analyses using correlation tests, the graft flow was found to significantly correlate with the grafted perfusion areas and the diameter of the bypassed coronary arteries. However, no significant difference was observed between the flow rates of the ITA grafts with and without stenosis or string phenomenon, but significant (P<0.0001) correlation was observed between the occurrence of a string sign and the degree of proximal stenosis of the recipient coronary artery. Regarding SV grafts, the mean flow rate of occluded grafts (29.2±20.5 ml/min) was significantly (P<0.0001) less than non-occluded grafts (56.4±29.9 ml/min). Conclusions: The bypass flow was affected by such a large number of factors that only measuring the bypass flow rate could not sufficiently predict either stenosed or narrowed grafts. However, ITA grafts bypassed to the coronary arteries with less stenosis were shown to more easily become narrowed.     

Effects of intra-aortic balloon pump on coronary artery bypass grafts blood flow: differences by graft type and coronary target

The intra-aortic balloon pump (IABP) is used worldwide as an anti-ischemic strategy. However, little is known about the modifications of the graft blood flow during IABP. A retrospective study aimed at analyzing transit-time flow measurements during 1:1 IABP and during its cessation in 401 consecutive patients receiving IABP before coronary artery bypass grafting (n = 880 graft segments) was reported. All normally functioning grafts were considered. Mean diastolic and mean blood flow improved significantly during 1:1 IABP compared with during IABP cessation (P < 0.001), although mean and end-diastolic arterial pressures were significantly lower (P = 0.001). Arterial and sequential saphenous vein (SV) grafts showed greater improvements in mean diastolic and mean flow compared with single venous grafts. Higher flows were also observed in the grafts directed to the circumflex territory. Surplus graft flow (SGF, defined as mean flow during 1:1 IABP/mean flow with IABP off) was recruited (SGF >1) during 1:1 IABP, with higher values in single arterial or sequential SV grafts versus single venous grafts (both P < 0.001). Y-conduit radial artery (RA) grafts showed higher maximum diastolic flow, mean flow, and SGF compared to aortocoronary RA or SV grafts. In this retrospective analysis, IABP was associated with improved diastolic and mean blood flow in bypass grafts. Arterial, sequential, and Y-conduit grafts were associated with greater improvements in blood flow and SGF than aortocoronary SV grafts.     

代谢综合征对不停跳冠状动脉旁路移植围术期的影响

目的 探讨代谢综合征(metabolic syndrome,MS)对不停跳冠状动脉旁路移植(OPCABG)围术期的影响.方法 2009年8月至2010年3月,连续1060例OPCABG病人分为MS组与非MS组,比较两组的病死率、房颤发生率、多器官衰竭评分(MODS)、心脏外科术后评分(PSCS)、PaO2/FiO2以及心率×中心静脉压/平均动脉压(pressure-adjusted heart rate,PAHR).结果 MS对OPCABG的病死率、房颤发生率、脑卒中、IABP和ECMO、透析的使用率无影响.但手术当天,MS组的MODS评分为2.57±1.62,PSCS评分为4.27±2.15,显著高于非MS组的2.15±1.65,3.92±2.29,P＜0.05;PaO2/FiO2在MS组为249.23±110.99,显著低于非MS组的283.33±114.35,P＜0.01;MS组的PAHR为9.98±3.54,显著高于非MS组的9.23±3.88,P＜0.05.手术后第1天,MS组的MODS评分为3.05±1.64.显著高于非Ms组的2.82±1.72,P＜0.05;PaO2/FiO2在MS组为277.11±122.99,显著低于非MS组,318.47±143.84,P＜0.05.结论 MS对OPCABG的病死率、房颤发生率、脑卒中、IABP和ECMO、透析的使用率无影响,但在术后当天和术后第1天,MS可以对OPCABG病人的呼吸和循环系统产生短暂的负面影响.

Abstract：

Objective Metabolic syndrome ( MS), a disorder involving multiple metabolic abnormalities such obesity,hypertension, diabetes or abnormal glucose tolerance and dyslipidemia, has been observed in many patients receiving coronary artery bypass procedures. In this study we try to examine the perioperative effects of metabolic syndrome on the off-pump coronary artery bypass (OPCABG). Methods A prospective study was conducted in 1060 consecutive OPCABG patients who were admited to Beijing Anzhen Hospital from July 2009 to March 2010. The patients were grouped as MS group and non-MS group according to the diagnostic criteria for Chinese metabolic syndrome. The outcomes such as mortality, atrial fibrillation,stroke, staying in ICU for more than three days, use of IABP, ECMO, dialysis, multiple organ dysfunction score ( MOOS) ,postoperative score for cardiac surgery (PSCS), PaO2/FiO2 , heart rate x central venous pressure/mean artery pressure(pressure-adjusted heart rate, PAHR) ,renal and liver function, platelets, and the dosage of vasoactive agents were analyzed and compared between the two groups by x2 test or t test. Results Three hundred and eighty-nine cases were diagnosed with MS among 1060 cases with OPCABG. In the MS group, 17 cases stayed in ICU for more than 3 days, 2 cases died, 76 had atrial fibrillation, 3 had stroke, 18 cases were treated with intra-aortic balloon counterpulsation (IABP). In the non-MS group, 47 cases stayed in ICU for more than 3 days, 12 cases died, 148 had atrial fibrillation, 3 had stroke, 48 cases were treated withIABP, 3 cases received ECMO and 4 cases received dialysis. No significant difference between MS group and non-MS group was identified in the aspects of mortality, atrial fibrillation, stroke, duration of more than three days in ICU, the use of IABP,ECMO, dialysis after OPACBG based on the x2 test(P＞0.05). However, on the operative days, the MODS and PSCS in MS group were significantly higher than that in non-MS group (P ＜ 0.05). MODS 2. 57 ± 1. 62 in MS group vs. 2. 15 ± 1.65 in non-MS group, PSCS 4.27 ±2.15 in MS group vs. 3.92 ±2.29 in non-MS group. PaO2/FiO2 in MS group was significantly lower than that in non-MS group (249.23 ± 110.99 vs. 283. 33 ± 114. 35), P ＜ 0. 01. PAHR in MS group was significantly higher than that in non-MS group (9.98 ±3.54 vs. 9.23 ±3. 88), P ＜0.05. On the first postoperative days, the MODS in MS group was also significantly higher than that in non-MS group (3.05 ±1.64 vs. 2.82 ± 1.72), P＜0.05. PaO2/FiO2 in MS group was significantly lower than that in non-MS group (277.11 ±122.99 vs.318.47 ±143.84), P＜0.05. Conclusion MS was not a predictor for death, atrial fibrillation, stroke, duration of more than three days in 1CU, the use of IABP, ECMO, dialysis after OPACBG. However, MS had a temporary adverse effect on the respiratory and circulatory systems on the operative day and the first postoperative day after OPCABG.     

Evaluation of coronary artery bypass grafts by intraoperative transit time flow measurement

Background: This study was conducted to evaluate the efficacy of transit time flowmetery in determining graft related problems per-operatively while performing coronary artery bypass grafting. Method: From May 2001 to January 2002 transit time flowmetery was performed on 442 grafts in 185 consecutive patients. A fixed protocol was used to assess the flow indices. Grafts were considered blocked if the pulsatility index was more than 5 and a systolic spike was present. Results: Abnormal flowmetery was observed in 10 grafts (2.26%). The mean flows for left internal mammary artery, radial and saphenous vein grafts were 28.24±18.12 ml/min., 37.57±21.81 ml/min., 28.8±17.17 ml/min. respectively. Nine of these grafts were revised with return of flow indices to normal. In one case the native vessel was small and of poor quality and revision was not possible. The 30-day mortality was 1.08%. There was no death attributable to graft malperfusion. Conclusion: Transit time flowmeter is a valuable tool in detecting graft related problems per-operatively. These problems can be corrected immediately thus reducing mortality and morbidity.     

Analysis of transit time flow of the right internal thoracic artery anastomosed to the left anterior descending artery compared to the left internal thoracic artery

Introduction

We evaluated with transit time flow the performance of the right and left thoracic arteries when used as a graft for the left anterior descending artery.

Methods

Fifty patients undergoing surgery for myocardial revascularization without cardiopulmonary bypass were divided into two groups. In group A patients received graft of right internal mammary artery to the anterior interventricular branch. In group B patients received graft of left internal mammary artery to the same branch. At the end of the operation the flow was assessed by measuring transit time.

Results

In group A, mean age was 60.6±9.49 years. The average height and weight of the group was 80.4±10.32 kg and 169.2±6.86 cm. The average number of grafts per patient in this group was 3.28±1.49. The mean flow and distal resistance obtained in right internal thoracic artery was 42.1±23.4 ml/min and 2.8±0.9 respectively. In group B, the mean age was 59.8±9.7 years. The average height and weight of this group was 77.7±14.22 kg and 166.0±8.2 cm. The average number of grafts per patient in this group was 3.08 ±0.82. The mean flow and distal resistance observed in this group was 34.2±19.1 ml/min and 2.0±0.7. There were no deaths in this series.

Conclusion

Right internal mammary artery presented a similar behavior to left internal mammary artery when anastomosed to the anterior interventricular branch of the left coronary artery. There was no statistical difference between the measured flow obtained between both arteries.     

EuroSCORE II and the importance of a local model,InsCor and the future SP-SCORE

Introduction

The most widely used model for predicting mortality in cardiac surgery was recently remodeled, but the doubts regarding its methodology and development have been reported.

Objective

The aim of this study was to assess the performance of the EuroSCORE II to predict mortality in patients undergoing coronary artery bypass grafts or valve surgery at our institution.

Methods

One thousand consecutive patients operated on coronary artery bypass grafts or valve surgery, between October 2008 and July 2009, were analyzed. The outcome of interest was in-hospital mortality. Calibration was performed by correlation between observed and expected mortality by Hosmer Lemeshow. Discrimination was calculated by the area under the ROC curve. The performance of the EuroSCORE II was compared with the EuroSCORE and InsCor (local model).

Results

In calibration, the Hosmer Lemeshow test was inappropriate for the EuroSCORE II (P=0.0003) and good for the EuroSCORE (P=0.593) and InsCor (P=0.184). However, the discrimination, the area under the ROC curve for EuroSCORE II was 0.81 [95% CI (0.76 to 0.85), P<0.001], for the EuroSCORE was 0.81 [95% CI (0.77 to 0.86), P<0.001] and for InsCor was 0.79 [95% CI (0.74-0.83), P<0.001] showing up properly for all.

Conclusion

The EuroSCORE II became more complex and resemblance to the international literature poorly calibrated to predict mortality in patients undergoing coronary artery bypass grafts or valve surgery at our institution. These data emphasize the importance of the local model.     

Incidence of postoperative atrial fibrillation in patients undergoing on-pump and off-pump coronary artery bypass grafting

Objective

To determine the incidence of postoperative atrial fibrillation in patients undergoing on-pump and off-pump coronary artery bypass grafting.

Methods

A retrospective study with analysis of 230 medical records between January 2011 and October 2013 was conducted.

Results

Fifty-six (24.3%) out of the 230 patients were female. The average age of patients undergoing on-pump coronary artery bypass grafting was 59.91±8.62 years old, and off-pump was 57.16±9.01 years old (P=0.0213). The average EuroSCORE for the on-pump group was 3.37%±3.08% and for the off-pump group was 3.13%±3% (P=0.5468). Eighteen (13.43%) patients who underwent off-pump coronary artery bypass grafting developed postoperative atrial fibrillation, whereas for the onpump group, 19 (19.79%) developed this arrhythmia, with no significant difference between the groups (P=0.1955).

Conclusion

Off-pump coronary artery bypass grafting did not reduce the incidence of atrial fibrillation in the postoperative period. Important predictors of risk for the development of this arrhythmia were identified as: patients older than 70 years old and presence of atrial fibrillation in perioperative period in both groups, and non-use of beta-blockers drugs postoperatively in the on-pump group.