MYOCARDIAL INFARCTION FOLLOWING CAROTID ENDARTERECTOMY

Myocardial infarction has been the major cause of mortality following operation for cerebrovascular insufficiency. In our institution, a clinical diagnosis of coronary artery disease was made in 37 of 125 (29.6%) consecutive male patients having carotid endarterectomy. Six of these 37 patients developed postoperative myocardial infarction. In contrast, none of the 88 patients without coronary artery disease developed myocardial infarction. A more recently treated group of 20 patients who had undergone carotid artery surgery and had previously undergone coronary artery bypass for angina did not develop postoperative myocardial infarction. These data suggest that in patients with both coronary artery and carotid artery disease, prior or concomitant coronary artery bypass should be considered. Myocardial infarction has been the leading cause of early and late death following operation for cerebrovascular insufficiency.(1) DeBakey(2) found operative mortality in patients having surgery for cerebrovascular insufficiency directly related to the incidence of coronary artery disease. An increased operative mortality due to reinfarction has been found in patients recovering from recent myocardial infarction.(3) Cooley(4) found that in patients having aortocoronary bypass there was no increased operative mortality 30 days after myocardial infarction and this may apply to patients having carotid endarterectomy. Subendocardial postoperative infarction associated with minor T wave changes and slight enzyme elevation had a better prognosis than did transmural infarction causing significant Q waves, sequential ST and T wave changes and marked enzyme elevations.(5) The purpose of this study was to document our experience with myocardial infarction in patients undergoing carotid artery operation for clinical coronary artery disease. Consideration of the role of saphenous vein bypass in those patients with coronary artery disease was the background for this review even though the evidence that myocardial infarction can be prevented with saphenous vein bypass operation is only preliminary at the present time.(6)     

Coronary Artery Disease with Single Coronary Artery

The authors have reviewed the literature in search of the coexistence of single coronary artery with significant coronary artery disease. Two cases of single right coronary artery are described. In both, the anomalies were unsuspected and diagnosed roentgenographically in life. Both patients had angina pectoris, positive graded-exercise stress tests, and hemodynamically significant obstruction or occlusion to the coronary arteries. In neither case was the stenosis proximal or amenable to bypass surgery.     

Selection and care of cardiac patients for plastic surgery

A major operation after successful coronary artery bypass surgery has been proved as safe as an operation for a patient free from coronary artery disease. Most patients with angina who demonstrate an operable coronary lesion should usually be scheduled for coronary artery bypass before undergoing nonemergency surgery. It is advisable to postpone elective plastic surgery for 6 weeks to 3 months after coronary bypass and 6 months after myocardial infarction. The life expectancy of cardiac patients must be carefully considered before elective plastic surgery, because performing an operation on a patient who cannot live to enjoy the benefits is unwise. Working together, cardiac surgeons, cardiologists, and plastic surgeons can now prolong the quantity of life and enrich its quality in properly selected and carefully managed patients.     

Scientific Section: Coronary Artery Surgery,Task Force Appointed by the Conference of Deputy Ministers of Health: 2. Results,indications and recommendations

The large majority of reported studies of patients treated by aortocoronary bypass have not been randomized clinical trials, and hence must be interpreted with great caution.Review of the seven randomized clinical trials in the literature leads to only one firm, positive conclusion: aortocoronary bypass results in a reduction in the morbidity of coronary artery disease, due to the alleviation of cardiac pain, for at least 3 years. In addition, there is some evidence that mortality for symptomatic patients with significant left main-stem coronary artery stenosis may be reduced by coronary artery bypass surgery. A significant effect on mortaliy form other forms of coronary artery disease has not yet been conclusively demonstrated but also has not been excluded. Most of the reports are preliminary and involve small numbers of patients followed for relatively short periods. The operation is still being improved. It is to be hoped that the randomized trials, involving large numbers of patients, now in progress will supply some of these answers.Aortocoronary bypass surgery is the treatment of choice for patients with stable cardiac pain that is disabling despite adequate treatment, or when adequate treatment is impractial; for patients with unstable cardiac pain, uncontrolled despite adequate treatment; and for symptomatic patients with critical stenosis of the left main-stem coronary artery.     

Combined surgical approach to carotid and coronary artery disease

The aim of this study was to compare two different surgical approaches to patients with coexistent significant carotid and coronary artery obstruction. Patients were treated with combined operation of carotid endarterectomy and coronary artery bypass grafting (CEA/CABG). The first group of patients underwent the CABG procedure with the cardiopulmonary bypass (CPB) on arrested heart and the second group without the CPB on a beating heart--off pump. Between May 15 1998, and October 9 2003, thirty-five consecutive patients underwent the combined procedure. In both groups there were no cases of transient or permanent perioperative neurological events. Overall, early mortality was 5.6%. The incidence of a perioperative myocardial infarction was 5.5%. In the follow-up period there were no cases of late stroke. According to the presented results in this study, it was found that the combined CEA and CABG is an equally safe and effective procedure performed with or without cardiopulmonary bypass for patients with a severe coexistent carotid and coronary artery disease.     

Cardiac evaluation and risk reduction in patients undergoing major vascular operations.

Occult coronary artery disease often accompanies symptomatic peripheral vascular disease and has an important effect on survival. Most perioperative and late fatalities after peripheral vascular operations are due to cardiac causes. Noninvasive cardiac testing can identify patients at increased risk for postoperative cardiac complications, although controversy exists regarding the optimal preoperative evaluation. Risk reduction strategies for patients known to be at high risk are also controversial. Some authors advocate coronary revascularization with coronary artery bypass grafting or percutaneous transluminal coronary angioplasty before the vascular procedure. Others believe that the combined morbidity and mortality of 2 operations exceed those of a peripheral vascular operation performed with aggressive monitoring and medical therapy. Continuous electrocardiographic monitoring after an operation has identified silent myocardial ischemia as a powerful predictor of cardiac complications. Ongoing research is likely to provide insights into the pathogenesis of postoperative cardiac complications and may lead to specific therapeutic interventions. Few prospective studies have been done in this area, and the threshold for preoperative and postoperative intervention is unknown. I review the literature and present an algorithm to guide cardiac testing and risk reduction in patients undergoing elective vascular surgical procedures.     

Right Internal Mammary Artery Implantation into Right Ventricular Myocardium for Revascularization of the Entire Heart: Experimental Data and Preliminary Report

The left internal mammary artery implant combined with epicardiectomy and free omental graft provides three extra-coronary sources of blood. This operation tested in dogs with 92% main-stem occlusion of three coronary arteries protected 75% of the animals. Applied clinically in over 100 patients, the operation resulted in 90% improvement. To obtain complete myocardial revascularization, the right internal mammary artery has been used as a fourth source of extra-coronary blood. In 57 animals, the right internal mammary arteries were implanted into the anterior walls of the right ventricle; in 80% this vessel formed anastomoses with the right coronary tree, and in 65% with the right and left coronary arteriolar systems. Six patients are described who underwent right internal mammary artery implantation; five of these in addition had the combined operation of left internal mammary artery implant, epicardiectomy and free omental graft. All patients had completely blocked right coronary arteries; in addition, five had advanced disease of the left coronary arterial tree.     

Selection of Patients for Coronary Artery Bypass Operations

Bypass operations have proved to be an effective treatment for advanced coronary artery disease. Randomized clinical trials have now shown that compared with medical treatment, bypass operations enhance survival in patients who have three-vessel disease or left main coronary stenosis. The goals of both medical and surgical treatment should be to improve a patient''s quality of life, extend survival and reduce medical care costs. Preliminary data suggest that bypass operations may be less costly than medical treatment in patients with severe angina that requires repeated or prolonged stays in hospital.     

Combined Internal Mammary Artery Implantation and Free Omental Graft Operation: A Highly Effective Revascularization Procedure: (A Study of 17 Cases)

One hundred and forty patients with coronary artery disease treated by internal mammary artery implantation were followed up from six months to 13 years. The mortality rate was 3%; improvement was obtained in 70%. Occlusive disease of all three major coronary arteries, however, requires more blood than can be supplied by the implant procedure, and the free omental graft operation was developed for the management of selected patients with this condition. Normally in animals triple coronary artery ameroid constriction results in 100% mortality. When the free omental graft operation, with or without internal mammary artery implantation, was performed, 80% of such animals survived. The free omental graft forms capillary anastomoses in three days and arteriolar vessels in eight days, which leave the base of the aorta, enter the omentum, thence to the myocardium. A combined internal mammary artery implantation and free omental graft operation was performed in 17 patients with triple coronary artery disease as shown by cine coronary arteriography. There was no operative mortality, and 12 of the patients are free of pain and have returned to work.     

Saphenous vein bypass grafting for coronary atherosclerosis: clinical experience

Saphenous vein bypass grafting is a recent and important procedure in the management of atherosclerotic coronary artery disease. A review of the first 150 patients operated on to July 1971 at the Toronto General Hospital is presented. Many had multiple bypass grafts and some had additional procedures including internal mammary artery implantation, valve replacement and scar tissue resection. There were five operative deaths (3%) and an additional five hospital deaths; the majority were related to myocardial infarction.A clinical review of the results six months to three years after operation indicates marked improvement in over 80% of the survivors. Postoperative hemodynamic studies were performed in many. It is suggested that patients with poor myocardial function presenting in failure may not benefit from the operation.     

Coronary artery bypass grafting (CABG): reassessing efficacy,safety, and cost

Based on randomized clinical trials begun in the 1970s showing the superiority of coronary artery bypass grafting (CABG) to medical management for patients with coronary artery disease (CAD), CABG has been routinely used to reduce angina and improve chances of survival in patients with CAD. Since CABG became a recognized standard treatment of CAD, considerable evidence has accumulated concerning the pathogenesis of CAD; the efficacy, risks, and costs of CABG; and the effectiveness of CAD risk factor reduction. To re-evaluate efficacy, safety, and cost of CABG, a MEDLINE search was performed to locate randomized trials comparing CABG vs nonsurgical management, CAD pathogenesis studies, and articles evaluating efficacy of coronary artery risk factor reduction behaviors. The extent of revascularization with CABG bore no relationship to relief of angina or survival. Randomized CABG vs medical management studies revealed that only patients with the most advanced CAD had improved survival, and this advantage vanished after 12 years. Researchers kept little coronary risk factor reduction data in the original CABG vs medical management randomized trials. However, in the Bypass Angioplasty Revascularization Intervention (BARI) study, surgically treated patients adopted lifestyles associated with lower coronary risk significantly more than patients treated with angioplasty. Factors other than revascularization cause the improvement in angina associated with CABG. Temporary survival advantages of CAD high-risk subgroups after CABG may be better explained by risk factor reduction rather than by revascularization. Using the BARI data, including lifestyle factors, a multivariate analysis of the influences determining survival and quality-of-life end points would test this hypothesis.     

Dextrocardia with situs inversus totalis: Cardiovascular surgery in three patients with concomitant coronary artery disease

Three patients with situs inversus totalis (mirror-image dextrocardia) and concomitant coronary artery disease were admitted to our institution for evaluation. In all cases, aortocoronary bypass grafting was successful. Patients with situs inversus and mirror-image dextrocardia are believed to have normal longevity, and, as these studies suggest, they have the same long-term prognosis after coronary bypass grafting as patients with situs solitus.     

Epidural morphine for outpatients with severe anginal pain.

Seven patients who had chronic coronary artery disease and had undergone coronary artery bypass surgery still suffered from anginal attacks several times daily despite optimal medical treatment. An epidural system of analgesia was implanted subcutaneously and treatment with epidural morphine started. The morphine was administered by the patients themselves or members of their family. During a median observation time of four months (range three to 11) all patients were free of pain while receiving this treatment.     

Numerical modeling of hemodynamics scenarios of patient-specific coronary artery bypass grafts

A fast computational framework is devised to the study of several configurations of patient-specific coronary artery bypass grafts. This is especially useful to perform a sensitivity analysis of the hemodynamics for different flow conditions occurring in native coronary arteries and bypass grafts, the investigation of the progression of the coronary artery disease and the choice of the most appropriate surgical procedure. A complete pipeline, from the acquisition of patient-specific medical images to fast parameterized computational simulations, is proposed. Complex surgical configurations employed in the clinical practice, such as Y-grafts and sequential grafts, are studied. A virtual surgery platform based on model reduction of unsteady Navier–Stokes equations for blood dynamics is proposed to carry out sensitivity analyses in a very rapid and reliable way. A specialized geometrical parameterization is employed to compare the effect of stenosis and anastomosis variation on the outcome of the surgery in several relevant cases.     

Exploration par tomodensitométrie multidétecteur du cœur et des artères coronaires

Due to its excellent spatial and temporal resolution, multislice computerized tomography (MSCT) allows visualizing the heart and coronary arteries. Although the indications of MSCT did not reach a consensus level yet, some trends can be stated. The advantages and limitations of MSCT in cardiac exploration are summarized in this article. The indications are mainly based on the excellent negative predictive value of MSCT regarding coronary artery disease. Hence, patients at low to moderate risk of coronary artery disease (CAD) mostly benefit of the technique. MSCT can be an alternate examination in case of non feasible or non contributive stress test. MSCT is highly contributive in the ostial analysis, in detecting abnormal coronary implantation or course, in assessing a reimplanted artery or in analysing bypass grafts. MSCT remains limited in patients with heavily calcified coronary arteries, and in patients with stented distal arteries.     

The Treatment of Multiple Coronary Occlusions by Internal Mammary Artery Implantation and Omental Graft: Report on Two Human Cases

The importance of triple coronary artery disease was evident in 125 patients undergoing internal mammary artery implantation, when some patients died from right coronary artery occlusion. This occurred even when the internal mammary artery was patent and revascularizing the left ventricle.In 1961 the free omental graft operation was developed to revascularize both right and left ventricles. In animals this operation has proved most effective in preventing death after application of Ameroid constrictors to all three coronary arteries. Arteriolar or larger-sized vessels rapidly formed between the aorta and omentum and the pericardium and omentum and the heart and omentum.Two patients with triple coronary artery disease underwent internal mammary artery implantation and free omental graft early in December 1962. Postoperative convalescence was uneventful. They have returned home and appear to be improved. Wrapping the entire heart with the free omental graft has produced little reaction, suggesting that, as in the animal, the grafts are surviving.     

Robotically assisted coronary endarterectomy

Robotic assistance has enabled coronary artery bypass surgery to be performed safely in a completely endoscopic fashion, but diffusely diseased target vessels may pose a technical challenge. We present a case in which coronary endarterectomy was performed on the left anterior descending coronary artery during a two-vessel totally endoscopic coronary artery bypass procedure. A 52-year-old woman presented with intermittent substernal pain. Preoperative studies showed diffuse disease in the left coronary artery system. Bilateral internal mammary arteries were harvested robotically using a skeletonized technique in a completely endoscopic fashion. Cardiopulmonary bypass was achieved via peripheral cannulation, and the heart was arrested with intermittent cold antegrade hyperkalemic blood cardioplegia delivered via an ascending aortic occlusion balloon catheter. The first obtuse marginal anastomosis was performed. The left anterior descending coronary artery was diffusely diseased and heavily calcified. An end-to-side anastomosis was attempted to the right internal mammary artery with unsatisfactory results. A localized coronary endarterectomy was performed, and an extended anastomosis was completed using the right internal mammary artery. The patient recovered uneventfully and was discharged home on postoperative day 6. Diffuse coronary artery disease was once thought to be a prohibitive challenge for minimally invasive coronary bypass procedures. This case demonstrates that local coronary endarterectomy is feasible and safe in robotic totally endoscopic coronary artery bypass surgery.     

Progress in noninvasive coronary artery imaging using multislice CT

Conventional coronary angiography (CAG) has been the reference standard for the assessment of coronary artery disease since its introduction in 1958. However, several studies have shown that diagnostic CAG has an average morbidity of 2% and a mortality of approximately 0.1%.In the last decade, progress in medical imaging has opened the way to noninvasive assessment of the coronary arteries at lower cost and risk. Of the different modalities, multislice CT (MSCT) has made the biggest step forward. At the 2005 European Congress of Radiology (ECR), experiences with the latest developments in noninvasive coronary artery imaging were reported. This report summarises the advances in the use of MSCT in coronary stenosis detection, emergency decision-making, plaque imaging, and the analysis of cardiac function and late enhancement. Also, attention is paid to new strategies to reduce MSCT-related radiation exposure.     

Towards the treatment of saphenous vein bypass graft failure--a perspective of the Bristol Heart Institute

Coronary artery bypass graft surgery (CABG) is widely used for the treatment of atheromatous stenosis of coronary arteries. However, as many as 50% of grafts fail within 10 years after CABG due to neointima (NI) formation, a process involving the proliferation and migration of vascular smooth muscle cells (VSMCs). Superimposed on neointima formation is accelerated atherogenesis which ultimately results in late vein graft failure. To date no therapeutic intervention has proved successful in treating late vein graft failure and as such is a matter of some urgency. However, in recent years, several diverse approaches aimed at preventing neointimal formation have been devised which have yielded promising results. These include the use of external stents, gene therapy as well as conventional pharmacological interventions. The objective of this article, therefore, is to review these recent approaches and their potential clinical applications in the treatment of vein graft disease.     

Revascularization in the acute coronary syndromes

Coronary heart disease is the leading cause of death worldwide, and occurs when the coronary arteries are unable to supply adequate oxygenated blood to the myocardium, which in turn can lead to ischemia and infarction of myocardial tissue. There are three options for revascularization in the setting of acute coronary syndromes. In select patients, coronary artery bypass surgery remains an option. Thrombolytics were initially the mainstay of therapy, which has now shifted to angioplasty, with or without stents, when readily available. Revascularization has been demonstrated to improve patient outcomes, and has evolved rapidly in the recent past.