Acute renal failure following cardiac surgery: incidence, outcomes and risk factors

Background: Acute renal failure (ARF) is a recognised complication following cardiac surgery, but the incidence varies widely in the published literature and there are no Australian data available to help predict the risks of ARF in patients with pre-existing renal disease. Aim: To determine the incidence, outcome and risk factors for ARF following cardiac surgery. Methods: A retrospective case control analysis of 903 consecutive patients who had cardiac surgery (795 CABG, 68 valve/septal surgery, 40 combined valve/CABG) in 1992-93. ARF was defined as doubling of serum creatinine concentration (Cr) to >0.13mmol/L if serum Cr was <0.13 mmol/L pre-operatively, or else a rise in serum Cr of 2:0.10 mmol/L after cardiac surgery. For each subject with ARF, two case control subjects were matched for date of surgery, surgeon, age, sex, type of surgery and pre-operative serum Cr to permit analysis of the influence of preoperative factors (hypertension, diabetes mellitus, left ventricular systolic dysfunction) and for the comparison of cardiopulmonary bypass time upon the development of ARF. Subsidiary endpoints were mortality, need for dialysis and length of hospital stay. Results: ARF developed in only 1.1% of patients with ‘normal’ pre-operative renal function (creatinine 0.13 mmol/L) and none required dialysis. ARF developed in 16%of those with impaired pre-operative renal function, 20% of whom required dialysis. Mortality from ARF was 13%. The risk of ARF rose from 10.4% in those with pre-operative serum Cr 0.14-0.20 mmol/L to 36.8% if the serum Cr was >0.20 mmol/L (p< 0.01). Mortality was higher (4.2%vs 0.7%, p< 0.01) and length of hospital stay longer (14.5 vs nine days [median], p< 0.001) in those with impaired pre-operative renal function. ARF was more likely in those over 65 years, if valve surgery was included and where there was prolonged cardiopulmonary bypass time. Conclusions: These data confirm that ARF following cardiac surgery is uncommon without preoperative impairment of renal function but currently carries a mortality rate of 13%. Impaired renal function alone is associated with higher mortality and prolonged hospital stay. Studies to prevent ARF in this setting should focus on the high risk subsets described in this study.     

Coronary artery revascularization: past, present, future: part II--newer technologies

Advances in coronary artery revascularization have been accompanied by clinical trials evaluating these advances. Part I of this paper addressed historic trials related to coronary artery revascularization. This paper reviews the data supporting newer revascularization strategies for our patients, including drug-eluting stents and off-pump coronary artery bypass surgery. Benefits include reduced repeat revascularization in patients who undergo percutaneous treatments with drug-eluting stents, the durability of surgical arterial revascularization, and the importance of medical therapy as the mainstay of treatment.     

Left atrial appendage occlusion: 2016 in review

A significant body of data has emerged in the area of Percutaneous Left Atrial Appendage Occlusion (LAAO). In this article, we present an overview of the most notable publications along with a review of the most important publications on LAAO in 2016. We also present important historical data such as landmark clinical studies, review of most utilized occlusion devices, and important clinical studies that are underway.

     

Left circumflex artery injury postmitral valve surgery,single center experience

The left circumflex (LCX) artery is located close to the mitral valve (MV), making it susceptible to injury during MV surgery. We are reporting our experience in the diagnosis and management of this complication. We retrospectively reviewed our surgical and coronary angiography databases for patients with documented LCX artery injury during MV surgery between January 2000 and December 2016. The complication was associated with MV replacement (9/1313, 0.7%) but not MV repair (0/393, 0.0%). Eight patients (88.9%) were female and the mean age was 40.4?±?14.2?years. There was roughly similar distribution of left and right dominant coronary circulations (5 and 4 patients, respectively). Eight patients (88.9%) had ischemic changes on electrocardiogram and ventricular arrhythmias were documented on six patients (66.7%). Three patients (33.3%) were treated with percutaneous coronary intervention while six patients (66.7%) required redo surgery to graft the LCX artery. The 30-day mortality was high (33.3%). A high index of suspicion is required to diagnose this injury. At the moment, no consensus is available on the optimal treatment strategy. We propose percutaneous approach as the first option to spare the patients from undergoing open-heart surgery for the second time.     

Noninvasive flow evaluations of coronary artery bypass grafting using dynamic cardiac CT

We aimed to investigate the correlation of graft flow measurements between transit-time flow measurement (TTFM) during coronary artery bypass grafting (CABG) surgery and dynamic cardiac CT after the surgery.Fourteen patients underwent CABG with TTFM and postoperative dynamic cardiac CT; 11 internal thoracic artery (ITA) grafts and 15 saphenous venous grafts (SVGs) were included for analysis. Pearsons correlation analysis was performed for the comparisons of the TTFM and cardiac dynamic CT flow parameters.TTFM was not significantly correlated with the CT flow of the ITA grafts (r = −0.23, P = .49), but it had a very strong correlation with the CT flow of the SVGs (r = 0.83, P < .01).In patients who underwent CABG surgery, dynamic cardiac CT enabled quantitative evaluation of SVG flow, with good correlation with TTFM.     

Videoscope-assisted cardiac surgery

Videoscope-assisted cardiac surgery (VACS) offers a minimally invasive platform for most cardiac operations such as coronary and valve procedures. It includes robotic and thoracoscopic approaches and each has strengths and weaknesses. The success depends on appropriate hardware setup, staff training, and troubleshooting efficiency. In our institution, we often use VACS for robotic left-internal-mammary-artery takedown, mitral valve repair, and various intra-cardiac operations such as tricuspid valve repair, combined Maze procedure, atrial septal defect repair, ventricular septal defect repair, etc. Hands-on reminders and updated references are provided for reader’s further understanding of the topic.     

Rapid diagnosis and management of intraoperative myocardial infarction during valvular surgery: using intraoperative transesophageal echocardiography followed by emergency coronary artery bypass grafting without coronary angiography

A 68-year-old man was admitted to undergo elective mitral valve surgery. Although the preoperative coronary angiography was normal, the patient suffered a myocardial infarction that resulted in untreatable collapsed hemodynamics. After inferring the responsible occluded coronary artery from the segmental wall motion abnormality detected in intraoperative transesophageal echocardiography, together with the anatomy found in preoperative coronary angiography, we performed an emergency coronary artery bypass graft surgery without a new angiography. This procedure resulted in survival of a potentially life-threatening situation. In selected cases, this therapeutic strategy may lead to reduction of mortality as a result of the intraoperative myocardial infarction.     

非体外循环冠状动脉搭桥术中转体外循环相关因素分析

目的探讨非体外循环冠状动脉搭桥术（OPCAB）中转体外循环（CPB）的相关因素。方法回顾性分析512例OPCAB患者的临床资料,以术中改行CPB为观察结果,采用单因素和多元逐步回归分析,筛选转OPCAB的相关因素,采用逐步判别分析的方法对筛选出的相关因素建立判别方程,并进行验证。结果急症手术、左心室射血分数、冠状动脉左主干病变、左心室舒张末期直径、室性心律失常、远端吻合口数目依次是OPCAB中改行CPB的相关因素。结论OPCAB中转CPB的相关因素比较复杂,可采用建立的判别方程进行判断。     

Anesthetic issues for robotic cardiac surgery

As innovative technology continues to be developed and is implemented into the realm of cardiac surgery, surgical teams, cardiothoracic anesthesiologists, and health centers are constantly looking for methods to improve patient outcomes and satisfaction. One of the more recent developments in cardiac surgical practice is minimally invasive robotic surgery. Its use has been documented in numerous publications, and its use has proliferated significantly over the past 15 years. The anesthesiology team must continue to develop and perfect special techniques to manage these patients perioperatively including lung isolation techniques and transesophageal echocardiography (TEE). This review article of recent scientific data and personal experience serves to explain some of the challenges, which the anesthetic team must manage, including patient and procedural factors, complications from one-lung ventilation (OLV) including hypoxia and hypercapnia, capnothorax, percutaneous cannulation for cardiopulmonary bypass, TEE guidance, as well as methods of intraoperative monitoring and analgesia. As existing minimally invasive techniques are perfected, and newer innovations are demonstrated, it is imperative that the cardiothoracic anesthesiologist must improve and maintain skills to guide these patients safely through the robotic procedure.     

Echocardiographic guidance and monitoring of left atrial appendage closure with AtriClip during open‐chest cardiac surgery

Left atrial appendage (LAA) closure prevents thromboembolic risk and avoids lifelong anticoagulation due to atrial fibrillation (AF). Nowadays, AtriClip, a modern epicardial device approved in June 2010, allows external and safe closure of LAA in patients undergoing cardiac surgery during other open‐chest cardiac surgical procedures. Such a surgical approach and its epicardial deployment differentiates LAA closure with AtriClip from percutaneous closure techniques such as Watchman (Boston Scientific, Marlborough, MA, USA), Lariat (SentreHEART Inc., Redwood City, CA, USA), and Amplatzer Amulet (St. Jude Medical, St. Paul, MN, USA) device procedures. AtriClip positioning must consider perioperative transesophageal echocardiography (TEE) to confirm LAA anatomical features, to explore the links with neighboring structures, and finally to assess its successful closure. We report a sequence of images to document the role of intraoperative TEE during an elective aortic valve replacement and LAA external closure with AtriClip.     

非体外循环和体外循环冠状架桥的效果和资源利用的比较

目的 :比较非体外循环 （off pum p）和体外循环 （CPB）冠状动脉架桥 （CABG）手术的效果和转归。方法 :113例患者接受 CABG手术 ,其中 5 9例采用 off pum p CABG,5 5例采用传统的 CABG,作者用回顾性分析的方法比较两组患者的手术时间 ,病变情况 ,拔管时间 ,ICU留住时间 ,出院时间和病死率。结果 :两组患者的手术时间 ,病变情况无明显差异 ,off pump组的拔管时间略早于 CPB组 （9∶ 15 ） ,但无统计学意义。 Off pum p组的 ICU留住时间和出院时间均明显短于 CPB组 ,off pum p组的病死率明显低于 CPB组。结论 :off pum p CABG较之传统的 CABG有较低的病死率 ,并能缩短 ICU留住时间和住院时间 ,因此减少医疗费用 ,节约医疗资源。     

Five year clinical follow up of patients who have had off pump coronary artery bypass grafting

Background: Off pump coronary artery bypass (OPCAB) has become a common technique for conducting coronary artery surgery. There has been some concern that the anastomoses might not be conducted as effectively on the beating heart, which could lead to poor long-term results. The aim of the present study was to follow up all patients who had undergone OPCAB at our institution to determine clinical outcomes up to 5 years postoperatively.

Methods: All living patients who had undergone OPCAB up until December 2000 were telephoned. For those who could be contacted, a detailed questionnaire was completed and the data were analysed.

Results: The technique of OPCAB was carried out on 312 patients. Thirteen of these patients died, five perioperatively. Actuarial survival at 5 years was 94.6% and freedom from cardiac related events was 92.1%. There were only two patients with angina worse than class I. Patients showed a high rate of compliance with risk factor management. Forty per cent of patients claimed to have had psychological problems related to the surgery.

Conclusions: Mid-term results of OPCAB are very satisfactory, but randomised trials are needed to see whether they are different from the results of conventional coronary artery bypass grafting.     

Verification of the Tip Position of the Intra-Aortic Balloon Pump Catheter by Perioperative Transesophageal Echocardiography

In some patients with advanced heart disease, low cardiac output may develop immediately after coronary artery bypass grafting (CABG). Appropriate measures are often required to ensure adequate perfusion of vital organs in such patients. Of the invasive rescue measures chosen for the support of low cardiac output, the intra-aortic balloon pump (IABP) prevails. In common practice, a fluoroscope or x-ray unit is used to guide the insertion of the IABP catheter to the correct position. Transesophageal echocardiography (TEE) can accomplish this more conveniently. Here we report on two cases of misplacement of the IABP catheter, one in the false lumen of a dissected upper abdominal aortic aneurysm and the other in the lumen of the inferior vena cava, both of which were diagnosed intraoperatively by TEE in CABG patients. The applications of TEE in the perioperative period are continuously expanding. One such application of TEE is the assessment of IABP catheter position.     

Myocardial Hematoma Documented by Transthoracic Echocardiography After Sequential Coronary Artery Stenting

We report the case of a patient who deteriorated suddenly while undergoing endoluminal coronary artery reconstruction with multiple stents to the left anterior descending coronary artery. With the aid of transthoracic echocardiography, a pericardial effusion was noted; however, dissection of the ventricular wall due to a large myocardial hematoma was also identified. Emergency exploration with evacuation of the pericardial blood with coronary artery bypass graft surgery was successfully accomplished. We discuss the possible factors that could have been associated with this unforeseen complication and the potential benefit of transthoracic echocardiography in early recognition.     

Effectiveness of triple-site triggered atrial pacing for prevention of atrial fibrillation after coronary artery bypass graft surgery

BACKGROUND: Recently, several temporary multisite pacing methods have been developed for prevention of postoperative atrial fibrillation (AF). HYPOTHESIS: In this study, we evaluated the effect of triple-site temporary triggered pacing in the AAT mode on the development of AF in patients undergoing coronary artery bypass graft (CABG) at high risk for developing postoperative AF. METHODS: A total of 70 patients undergoing CABG were randomly assigned either to pacing group (study group, n = 35 patients) or to no pacing group (control group, n = 35 patients). The external pacemaker was programmed to pace at the atrial triggered mode at a lower rate of 40 beats/min for 4 days. RESULTS: Atrial fibrillation, defined as lasting > 30 s, occurred in 4 patients (11.4%) in the study group and in 16 patients (45.7%) in the control group (p = 0.003). Sustained AF, defined as AF lasting > 10 min, also was observed less frequently in the study group than in the control group (11.6 vs. 37.1%, p = 0.024). Triple-site triggered atrial pacing was observed to reduce the incidence of AF by 75% and the incidence of sustained AF by 69%. CONCLUSIONS: We believe that multiple-site temporary pacing in the triggered mode is an effective way of preventing postoperative AF. This technique may be used especially in patients at high risk of developing AF.     

非体外循环下冠状动脉搭桥术的麻醉管理

目的 :总结 2 8例非体外循环下多支冠状动脉搭桥术的麻醉管理。方法 :术前依据患者心脏功能及全身状况 ,给予营养心肌、扩冠、降压、利尿等治疗。采用静吸复合麻醉 ,气管插管控制呼吸 ,在非体外循环下行冠状动脉搭桥术。结果 :手术期间 4例血压过低 ,2例 ST段显著抬高伴室性心律失常 ,改为体外循环辅助下手术 ,余 2 2例术中血流动力学平稳。术毕非体外循环组 2 2例 6～ 8h内拔管 ,明显少于体外循环组 （10～ 16h）。 2 8例预后良好 ,无麻醉并发症。结论 :维持血流动力学平稳和心肌氧供需平衡 ,是非体外循环下冠状动脉搭桥术麻醉的关键     

Characterization of a saphenous vein graft aneurysm by intravascular ultrasound and computerized three-dimensional reconstruction

Aneurysmal dilatations in saphenous vein grafts are rare complications of coronary artery bypass surgery that mostly represent thin-wall pseudoaneurysms at anastomotic sites. We describe a case of an enlarging distal saphenous vein graft aneurysm in which intravascular ultrasound (IVUS) and computerized three-dimensional reconstruction (3DR) of the IVUS images was performed to conclusively demonstrate true aneurysm morphology. Although both atherosclerotic and nonatherosclerotic mechanisms for vein graft aneurysm formation have been previously suggested, IVUS images and 3DR of the aneurysm in this case did not reveal any of the features typical for atherosclerotic lesions. Further, the IVUS images and 3DR suggest that progressive atherosclerosis is not the likely cause of aneurysm formation in this case. This application of IVUS and 3DR provides detailed information about saphenous vein graft aneurysm structure, clues to aneurysm formation, and suggests a natural history that may differ from that of pseudoaneurysms. © 1993 Wiley-Liss, Inc.     

Good outcomes from cardiac surgery in the over 70s

OBJECTIVE: To determine the early mortality and major morbidity associated with cardiac surgery in the elderly. DESIGN: Retrospective case record review study of 575 patients >/= 70 years old who underwent cardiac surgery at the Manchester Heart Centre between January 1990 and December 1996. SETTING: Regional cardiothoracic centre. SUBJECTS: Patients >/= 70 years old who underwent cardiac surgery. MAIN OUTCOME MEASURES: Comparison of 30 day mortality and incidence of major morbidity between patients >/= 70 years old and patients < 70 years old. RESULTS: Of 4395 cardiac surgical operations, 575 operations (13.1%) were in patients aged >/= 70 years (mean (SD) 73.1 (3.2) years). The proportion of elderly patients rose progressively from 7.9% in 1990 to 16.5% in 1996. 334 patients (58.1%) had coronary artery bypass grafting alone, 91 patients (15.8%) had valve surgery alone, and 129 patients (22.4%) had combined valve surgery and bypass grafting. For isolated coronary artery bypass grafting, 30 day mortality in patients >/= 70 years was 3.9% compared with 1.3% in patients < 70 years (p < 0.001). 30 day mortality for isolated valve surgery in patients >/= 70 years was 7.7%. Isolated aortic valve replacement was the most common valvar procedure in patients >/= 70 years and carried the lowest mortality (4.3%). Additional coronary artery bypass grafting increased the mortality rate in patients >/= 70 years to 9.3% for all valve surgery and to 8.0% for aortic valve replacement. Major morbidity in patients >/= 70 years was low for all procedure types (stroke 1.9%, acute renal failure requiring dialysis 1.6%, perioperative myocardial infarction 0.5%). CONCLUSIONS: Early mortality and major morbidity is low for cardiac surgery in elderly patients. Concerns over the risk of cardiac surgery in the elderly should not prevent referral, and elderly patients usually do well. However, unconscious rationing of health care may affect referral patterns, and studies that assess the cost effectiveness of cardiac surgery versus conservative management in such patients are lacking.