A comparison of sufentanil vs. remifentanil in fast-track cardiac surgery patients.

We retrospectively compared patients receiving remifentanil with patients receiving sufentanil undergoing fast-track cardiac surgery. After 1:1 propensity score matching there were 609 patients in each group. The sufentanil group had a significantly longer mean (SD) ventilation time compared with the remifentanil group; 122 (59) vs. 80 (44) min, p < 0.001 and longer mean (SD) length of stay in the recovery area; 277 (77) vs. 263 (78) min, p = 0.002. The sufentanil group had a lower mean (SD) visual analogue pain score than the remifentanil group; 1.5 (1.2) vs. 2.4 (1.5), p < 0.001 and consumed less mean (SD) piritramide (an opioid analgesic used in our hospital); 2.6 (4.7) vs. 18.9 (7.3) mg, p < 0.001. The results of our study show that although remifentanil was more effective in reducing time to tracheal extubation and length of stay in the recovery area, there was an increased requirement for postoperative analgesia when remifentanil was used.

Experience with anatomically orientated devices for transapical aortic valve implantation.

Transcatheter aortic valve implantation (TAVI) is a new technology, which is rapidly growing to a routine procedure amenable for patients with symptomatic aortic valve stenosis and higher than average risk for conventional aortic valve surgery. The crucial disadvantage of TAVI remains the not well foreseeable risk of more than trivial degree of paravalvular leakage and a high rate of atrioventricular block and consecutive pacemaker implantation. In addition, current implantation techniques do not allow controlling the rotation of first-generation devices that might be beneficial regarding optimal physiological valve performance, optimal coronary flow and avoidance of placement of covered commissures in front of the coronary ostia. These shortcomings had pushed the development of second-generation self-expandable nitinol-based devices for subcoronary implantation that aim a reduction of paravalvular leak and AV-block by anatomical orientated positioning into the aortic root. This review focuses on the description of three different TAVI concepts, which are presently under early clinical evaluation, or have recently received commercial approval, using the transapical approach.

Acute aortic dissection type A.

BACKGROUND: Acute aortic dissection type A (AADA) is a life-threatening vascular emergency. Clinical presentation ranges from pain related to the acute event, collapse due to aortic rupture or pericardial tamponade, or manifestations of organ or limb ischaemia. The purpose of this review was to clarify important clinical issues of AADA management, with a focus on diagnostic and therapeutic challenges. METHODS: Based on a MEDLINE search the latest literature on this topic was reviewed. Results from the German Registry for Acute Aortic Dissection Type A (GERAADA) are also described. RESULTS: Currently, the perioperative mortality rate of AADA is below 20 per cent, the rate of definitive postoperative neurological impairment approaches 12 per cent and the long-term prognosis after surviving the acute phase of the disease is good. Many pathology- and therapy-associated factors influence the outcome of AADA, including prompt diagnosis with computed tomography and better cerebral protection strategies during aortic arch reconstruction. Endovascular technologies are emerging that may lead to less invasive treatment options. CONCLUSION: AADA is an emergency that can present with a wide variety of clinical scenarios. Advances in the surgical management of this complex disease are improving outcomes.

Patent foramen ovale. Correct route for implantation of a biventricular permanent pacemaker?

INTRODUCTION: Intentional or unintentional placement of a pacemaker lead into the left ventricle is an uncommon clinical entity that is associated with a high risk for systemic embolization and enormous difficulties in case of explantation. Unintentional implantation through a patent foramen ovale via the mitral valve is the usual pathway for this malposition. METHODS: We report a case where a pacemaker lead was placed intentionally into the left ventricle via a patent foramen ovale for biventricular pacing for resynchronization therapy. Later, the patient developed life-threatening pacemaker lead-associated endocarditis with sepsis. Emergency open heart surgery for lead removal was necessary in the form of a reoperation after bypass graft surgery a number of years earlier. CONCLUSION: Although it is technically feasible to implant the pacemaker lead into the left ventricle via a patent foramen ovale, we consider this option to be obsolete for use with a biventricular pacemaker, due to the multitude of risks, which can, in part, be life-threatening for the patient.

Prediction of the annuloplasty ring size in patients undergoing mitral valve repair using real-time three-dimensional transoesophageal echocardiography.

AIMS: We sought to investigate the additional value of real-time three-dimensional transoesophageal echocardiography (RT 3D TOE)-guided sizing for predicting annuloplasty ring size during mitral valve repair. METHODS AND RESULTS: In 53 patients undergoing elective mitral valve repair, an RT 3D TOE was performed pre- and post-operatively. The digitally stored loops were imported into a software for mitral valve assessment. The annuloplasty ring size was predicted by superimposing computer-aided design (CAD) models of annuloplasty rings onto Live 3D zoom loops, measurement of the intercommissural distance, or the height of the anterior mitral leaflet. The surgeon implanted the annuloplasty ring according to the usual surgical technique and was blinded to the echocardiographic measurement results. Pre-operative correlation between the selected ring size with mitral valve assessment and the actual implanted annuloplasty ring size was 0.91. The correlation for measurement of the intercommissural distance was 0.55 and for measurement of the height of the anterior mitral leaflet 0.75. The post-operative correlation with the actual implanted ring size was 0.96 for mitral valve assessment, 0.92 for intercommissural distance, and 0.79 for the anterior mitral leaflet height. CONCLUSION: Superimposition of annuloplasty ring CAD models on the Live 3D zoom loops of the mitral valve using mitral valve assessment is superior to two-dimensional measurements of the intercommissural distance or the height of the anterior mitral leaflet in predicting correct annuloplasty ring size.

Dislocation of a transapically implanted aortic valve prosthesis with a functionally bicuspid aortic valve and ascending aortic aneurysm.

In recent years, catheter-based aortic valve interventions have become established procedures for the treatment of high-risk and advanced age patients with aortic valve pathologies. One of the limitations of the widespread applicability of this procedure is the annulus size. Until recently, no prosthesis was available to treat patients with a large annulus. We report on a patient with high-grade aortic stenosis (AS) and a 27-mm annulus, who underwent transapical implantation (TAP) of an Edwards SAPIEN® 29-mm prosthesis (Edwards LifeScience, Irvine, CA, USA). Due to insufficient dilation of his heavily calcified, functionally bicuspid aortic valve leaflets during balloon aortic valvuloplasty (BAV), the TAP prosthesis did not anchor adequately. This was determined during follow-up as he developed progressive aortic insufficiency and orthopnea, and an echocardiography revealed that the valve had been displaced into the LVOT. A conventional aortic valve replacement and ascending aorta replacement were performed, at which time the TAP prosthesis was removed. The patient recovered uneventfully, and was discharged with a well-functioning aortic bioprosthetic valve and in good general condition.

Late onset Takotsubo cardiomyopathy after mitral valve replacement.

We report a case of delayed onset Takotsubo cardiomyopathy (TC) in a 69-year-old woman, associated with minor stressors, two weeks after mitral valve replacement. After suffering several minor complications she had fully recovered and her discharge was planned. On the 14th postoperative day she had to be resuscitated due to cardiogenic shock. TC was diagnosed based on reduced ventricular function with apical ballooning and normal coronaries. Treatment with catecholamines and intra-aortic balloon pump led to full recovery. She continues to do well two years after surgery. TC should be considered as a potential cause of delayed ventricular dysfunction in postcardiac surgery patients.

Mitral valve re-replacement in a patient with osteogenesis imperfecta.

A 34-year-old patient with osteogenesis imperfecta (OI) underwent previous double-valve replacement in the aortic and mitral valve position. Bioprostheses were implanted because of an elevated risk of daily injury. Five years later the patient underwent re-replacement of the stenotic stentless mitral valve prosthesis. A right anterolateral mini-thoracotomy was used for operative access during both procedures, in order to preserve thorax stability. Patients with OI may benefit from minimally invasive valve surgery for primary procedures or reoperation.

Pacemaker-associated thrombotic occlusion of the inferior vena cava causing liver failure.

Pacemaker implantation using endocardial leads can give rise to thrombotic venous occlusion. We report the case of a 23-year-old male with transposition of the great arteries, who had previously undergone a Senning repair at the age of one year. A sick sinus syndrome required pacemaker implantation with subsequent multiple lead revisions. Following the implantation of the last lead, the patient developed complete occlusion of the inferior vena cava (IVC) with stenosis of the superior vena cava (SVC) with pacemaker leads in both lesions. Liver failure, ascites and esophageal varices developed. Thrombolytic treatment was ineffective; finally the patient was listed for liver transplantation. We explanted the lead embedding the thrombosis, together with some lead remnants. The stenosis of the SVC and the occlusion of the IVC were dilatated and stabilized with four stents. Over a follow-up period of 4 months, NYHA class improved from NYHA III to NYHA I-II, the hepatic function showed complete remission, and a liver transplantation was not necessary.

Late perforation of a right ventricular pacing lead: a potentially dangerous complication.

Four days after uncomplicated implantation of a two-chamber pacemaker and a normal postoperative course, a patient was referred to our hospital with left-sided hemothorax and early hemorrhagic shock. Chest X-ray and CT scan were suspicious of a right ventricular lead perforation with additional pericardial and pleural injury. Immediate surgery was performed via a lateral thoracotomy and the perforation was repaired via direct suture. An epimyocardial ventricular lead was implanted simultaneously. The patient made an uneventful recovery.

Implications of a congenitally abnormal valve: a study of 1025 consecutively excised aortic valves.

BACKGROUND: An increasing proportion of patients with congenitally abnormal aortic valves (AV) present for AV replacement. AIMS: To review morphological changes in a large contemporary patient population undergoing AV replacement. METHODS: A detailed review was conducted for all 1025 patients who underwent AV replacement from 2002 to 2005, including the clinical indication for surgery, the type of native AV disease, the pathological changes observed in each valve and the need for related surgery. RESULTS: Tricuspid (TAV), bicuspid (BAV) and unicuspid (UAV) aortic valves were observed in 64.5%, 31.9% and 3.0% of all patients respectively. A decreased number of cusps was associated with increasing predilection for male gender (83.9%, 73.4%, 59.2% for UAV, BAV, TAV respectively), a younger patient age at surgery (41.6 (14.3), 61.3 (12.8), 67.5 (12.9) years), and an increased occurrence of pathological changes in the cusps, including calcification of both the cusp and the base, ossification and ulceration. UAV and BAV were also associated with increasing replacement of the ascending aorta due to dilatation and aneurysm formation (54.8, 38.8%, 16.6%). The incidence of infective endocarditis and rheumatic heart disease was 3.8% and 11.2% of all excised valves respectively. CONCLUSION: UAV and BAV were increasingly likely to affect men, fail at an earlier age, and show an increasing incidence of pathological changes in the cusps and ascending aorta than TAV. These results suggest that TAV, BAV and UAV may represent a phenotypic continuum of a similar disease process.

Surgical therapy of ventricular arrhythmias.

Since the advent of implantable cardioverters/defibrillators (ICD) and percutaneous ablation, surgery for the treatment of ventricular arrhythmia has decreased tremendously. Nevertheless, surgical treatment of ventricular arrhythmias is still required, especially for cases where ICD discharge occurs very frequently or in patients with other indications for surgery. The choice of surgical therapy may range from radiofrequency- or cryoablation of a single focus (identified either intra- operatively or percutaneously) to more extensive surgical procedures such as surgical ventricular reconstruction with endocardial resection or even resection of the right ventricle and the creation of a cavo-pulmonary circulation for malignant arrhythmias and right ventricular failure in patients with arrhythmogenic right ventricular dysplasia. However, the choice of surgical procedure should be made based on the pathomechanism of the arrhythmia. This is important because any incision in the left or right ventricle or percutaneous ablation may also be the cause for ventricular arrhythmia. In this short review we will describe the most common underlying substrates for ventricular arrhythmia, indications for surgery, the techniques used for treatment and the results achieved. We will conclude that for most cases of patients with ventricular arrhythmia undergoing surgery, ischemia and the presence of a scar after myocardial infarction is the underlying cause and revascularization plus surgical ventricular reconstruction with endocardial resection may be the best treatment option.

Long-term results of bioprosthetic mitral valve replacement: the pericardial perspective.

Pericardial valve bioprostheses were introduced in early 1970s and were widely used in the 1980s. The longterm results with the Ionescu-Shiley valve, the first commercially available pericardial valve, were disappointing because of high rate cusp tears during the first decade after implantation. The enthusiasm for this type of bioprosthetic valve was further hampered by the premature failure of the Hancock pericardial valve. The long-term results of aortic valve replacement with the Carpentier-Edwards pericardial valve, which was introduced in 1981, indicated that that valve was durable and the issue of cusp tears had been resolved by an appropriate design. This knowledge prompted surgeons to revisit the merits of pericardial valves for mitral valve replacement and several other pericardial valves are now commercially available. The largest data on long-term results are with the Carpentier-Edwards pericardial mitral valve. The reported freedom from structure valve failure ranged from 69% to 85% at 10 years in patient population with mean age of 60 to 70 years. Young age is a major determinant of valve failure, which is largely due to calcification. There are also long-term data, albeit more limited on the Sorin Pericarbon and Mitroflow valves used for mitral valve replacement. This paper review the published experience with various pericardial bioprosthetic valves used for mitral valve replacement during the past 3 decades.

Is profound hypothermia required for storage of cardiac allografts?

BACKGROUND: Improved methods of cardiac allograft protection are required to expand the pool of potentially available organs and to enhance the recovery of grafts subjected to prolonged ischemia. We have previously demonstrated that limited coronary perfusion provided by donor blood harvested at the time of organ procurement can improve both metabolic and functional recovery after transplantation. In this study we evaluated the hypothesis that limited coronary perfusion may enable prolonged cardiac storage while avoiding the potentially detrimental effects of profound hypothermia. METHODS: Fourteen orthotopic cardiac transplants were performed in female Yorkshire pigs by using donor blood perfusion during 5 hours of either tepid (25 degrees C) or cold (4 degrees C) storage. Assessments of myocardial metabolism and function were performed at baseline and after 45 minutes of normothermic (37 degrees C) reperfusion. RESULTS: Hearts protected with tepid perfusion displayed improved recovery of myocardial function (89% +/- 18% vs 63% +/- 25%, P =.05). Diastolic compliance was adversely affected in both groups after transplantation. Aerobic myocardial metabolism was better preserved in the tepid group. CONCLUSIONS: Profound hypothermia results in depressed myocardial metabolic and functional recovery after transplantation. Limited coronary perfusion with shed donor blood can permit cardiac allograft storage at tepid temperatures, resulting in improved myocardial performance.

Management of patients with concomitant coronary and carotid vascular disease.

Stroke is a major complication of coronary artery bypass graft (CABG) surgery. Carotid stenosis is an important cause of stroke in certain CABG patients. Randomized trials have revealed that carotid endarterectomy (CEA) is clearly indicated in non-CABG patients with symptomatic severe carotid stenosis. CEA is also indicated in patients with symptomatic moderate stenosis and asymptomatic severe stenosis if the predicted incidence of perioperative morbidity and mortality is low. Therapeutic options for patients with concomitant coronary and carotid disease include CABG alone, CABG plus CEA, and CABG plus carotid stenting. In this article we discuss each of these management techniques in detail, and make recommendations regarding the preferred approach in specific patient populations.

Lactate release during reperfusion predicts low cardiac output syndrome after coronary bypass surgery.

BACKGROUND: Cardioplegic arrest induces anaerobic myocardial metabolism with a net production of lactate from glycolysis. However, persistent lactate release during reperfusion suggests a delayed recovery of normal aerobic metabolism and may lead to depressed myocardial function necessitating inotropic or intraaortic balloon pump support (low output syndrome [LOS]). We examined the relation between perioperative myocardial metabolism and postoperative clinical outcomes in patients undergoing isolated coronary artery bypass surgery (CABG). METHODS: We reviewed 623 patients who were enrolled in clinical studies evaluating perioperative myocardial metabolism between 1983 and 1996. Arterial and coronary sinus blood samples were obtained intraoperatively to assess myocardial metabolism. Clinical data regarding patient demographics and postoperative outcomes were prospectively collected and entered into our institutional database. RESULTS: Low output syndrome developed in 36 patients (5.8%). Myocardial lactate release was higher in these patients compared with those who did not develop postoperative LOS. Advanced age and poor preoperative left ventricular function were independent predictors of lactate release during reperfusion. Persistent lactate release after 5 minutes of reperfusion was the only independent predictor of postoperative LOS in this low-risk population. CONCLUSIONS: Persistent lactate release during reperfusion occurs in a significant proportion of low-risk patients undergoing isolated CABG and is an independent predictor of postoperative low cardiac output syndrome. Persistent lactate release during reperfusion suggests a delayed recovery of aerobic myocardial metabolism and may be related to intraoperative misadventure or inadequate myocardial protection. Myocardial lactate release may be useful as an alternative end-point in clinical trials evaluating perioperative myocardial protection.

Stroke during coronary bypass surgery: principal role of cerebral macroemboli.

OBJECTIVE: The purpose of this study was to gain insight into the etiology of stroke during coronary bypass surgery. METHODS: Retrospective review of prospectively gathered data on 6682 consecutive coronary bypass patients. Patients undergoing simultaneous procedures, including carotid endarterectomy, were excluded. We performed a systematic chart review of all patients who suffered a perioperative stroke. Predictors of stroke were determined with stepwise logistic regression analysis. RESULTS: The prevalence of stroke was 1.5% (n=98). Stroke patients had significantly increased intensive care unit and hospital length of stays, as well as increased mortality when compared to patients without stroke (all P< 0.001). Independent predictors of stroke were (in decreasing order of magnitude): age >70 years, left ventricular ejection fraction <40%, previous stroke or transient ischemic attack, normothermic cardiopulmonary bypass, diabetes, and peripheral vascular disease. Chart review revealed that the probable cause of stroke was macroemboli, likely from ascending aorta atherosclerosis, in 37% of patients and unknown in 38% of patients. Computerized tomography (CT) scans were obtained in 79 patients (81%). Lesions detected by CT were consistent with a macroembolic etiology: nearly all lesions were ischemic in nature and located in the distribution of major cerebral arteries, particularly the middle cerebral artery. CONCLUSIONS: Stroke is a devastating complication of coronary bypass surgery. Our multivariable risk factors for stroke, chart review, and CT findings all suggest that macroemboli, presumably from the ascending aorta, are the predominant cause of stroke during coronary bypass surgery. Future studies should be directed at minimizing the risk of embolization during cardiac surgery.

The effect of insulin cardioplegia on atrial fibrillation after high-risk coronary bypass surgery: a double-blinded, randomized, controlled trial.

UNLABELLED: Atrial fibrillation after coronary bypass (CABG) surgery is an important cause of morbidity and increased resource utilization. Insulin-enhanced cardioplegia may reduce postoperative arrhythmias by improving aerobic myocardial metabolism and mitigating the deleterious effects of ischemia. We performed a double-blinded, randomized, controlled clinical trial to determine if insulin-enhanced cardioplegia decreases the risk of post-CABG atrial fibrillation in a high-risk patient population. We randomized 501 patients undergoing urgent CABG to receive insulin-enhanced (Humulin R 10 IU/L, Insulin group, n = 243) or standard (Control group, n = 258) blood cardioplegia during cardiopulmonary bypass. Patients were monitored by using continuous electrocardiography for a minimum of 3 days postoperatively. All standard cardiac medications, including beta-adrenergic blockers, were continued postoperatively. Insulin-enhanced cardioplegia did not result in a significant reduction in postoperative atrial fibrillation. Furthermore, we failed to detect a difference in the incidence of conduction defects, ventricular tachycardia, or pacemaker requirements between insulin and placebo patients. Atrial fibrillation was the most common arrhythmia, occurring in 31% of all patients. Independent predictors of atrial fibrillation were elderly age, preoperative atrial fibrillation, and renal insufficiency. Right bundle branch block was the most common conduction abnormality. Predictors of right bundle branch block were elderly age, female sex, and circumflex coronary artery disease. The incidence of postoperative ventricular tachycardia, left bundle branch block, and permanent pacemaker requirement was small. We conclude that insulin-enhanced cardioplegia does not reduce the incidence of postoperative atrial fibrillation in high-risk CABG patients. IMPLICATIONS: We conducted a double-blinded, randomized, placebo-controlled trial of insulin-enhanced cardioplegia in 501 patients undergoing urgent coronary bypass surgery. Insulin did not decrease the incidence of postoperative atrial fibrillation when compared with placebo. We also failed to demonstrate a difference in the incidence of other postoperative arrhythmias between the two groups of patients.

Neuropsychologic impairment after coronary bypass surgery: effect of gaseous microemboli during perfusionist interventions.

OBJECTIVE: Neuropsychologic impairment is a common complication of coronary bypass surgery. Cerebral microemboli during cardiopulmonary bypass are the principal cause of cognitive deficits after coronary bypass grafting. We have previously demonstrated that the majority of cerebral emboli occur during perfusionist interventions (ie, during the injection of air into the venous side of the cardiopulmonary bypass circuit). The purpose of this study was to determine whether an increase in perfusionist interventions is associated with an increased risk of postoperative cognitive impairment. METHODS: Patients undergoing elective coronary artery bypass grafting (n = 83) underwent a battery of neuropsychologic tests preoperatively and 3 months postoperatively. Patients were divided into 2 groups according to the median value of perfusionist interventions during cardiopulmonary bypass. Group 1 patients (n = 42) had fewer than 10 perfusionist interventions, and group 2 patients (n = 41) had 10 or more interventions. RESULTS: The 2 groups of patients were similar for all preoperative, intraoperative, and postoperative variables, with the exception of longer cardiopulmonary bypass times in group 2 patients (P <.001). Group 2 patients had lower mean scores on 9 of 10 neuropsychologic tests, with 3 (Rey Auditory Verbal Learning, Digit Span, and Visual Span) being statistically significant. Group 2 patients had worse cognitive test scores, even when controlling for increased bypass times. Group 2 patients had a nonsignificant trend toward an increased prevalence of neuropsychologic impairment 3 months postoperatively. CONCLUSIONS: Introduction of air into the cardiopulmonary bypass circuit by perfusionists, resulting in cerebral microembolization, may contribute to postoperative cognitive impairment.

Effects of metabolic stimulation on cardiac allograft recovery.

BACKGROUND: We previously demonstrated that continuous perfusion of cardiac allografts during hypothermic storage with donor blood harvested at the time of organ retrieval improves myocardial recovery after transplantation. However, myocardial metabolism and function remain depressed compared to base line values. This study evaluated the use of a continuous infusion of donor blood enhanced with insulin to augment aerobic myocardial metabolism during and after hypothermic storage. METHODS: Yorkshire pigs (45 to 50 kg) were used to perform 14 orthotopic cardiac transplants using either continuous perfusion with donor blood (blood group, n = 7) or perfusion with donor blood enhanced with 10 IU/L insulin (insulin group, n = 7). After heparinization, hypothermic (4 degrees C) cardioplegic arrest, and donor heart extraction, donor blood (2,844 +/- 210 mL) was harvested in both groups and perfused at room temperature (20 degrees C) at a pressure of 60 mm Hg for 3 hours. Blood cardioplegia was delivered after each anastomosis in both groups and arterial and coronary sinus blood samples were obtained to examine myocardial metabolism. A Millar micromanometer was used to measure left ventricular developed pressure and the rate-pressure product at varying preloads. RESULTS: There were no differences in either myocardial lactate or acid release between the two groups. Hearts in the insulin group displayed higher myocardial oxygen extraction than those in the blood group. The recovery of developed pressure was higher in the insulin group compared to the blood group (91% +/- 19% vs 73% +/- 2%, p = 0.04). CONCLUSIONS: In this model, continuous perfusion of cardiac allografts with donor blood and insulin preserves myocardial metabolism during hypothermic storage and improves metabolic and functional recovery after orthotopic cardiac transplantation.