Coronary endothelial injury after local occlusion on the human beating heart.

Background: Occlusion of coronary arteries during beating heart surgery bears the potential for mechanical trauma to the arterial wall with consequent endothelial injury. The aim of this study was to elucidate the effects of local occlusion on the beating heart in human coronary arteries.

Methods: Coronary arteries of patients with dilated cardiomyopathy (n = 7) or ischemic heart disease (n = 10) undergoing heart transplantation were locally occluded after starting cardiopulmonary bypass.

The subclavian and axillary arteries as inflow vessels for coronary artery bypass grafts--combined experience from three cardiac surgery centers.

Background: The subclavian and axillary arteries represent reliable inflow vessels in peripheral vascular surgery. During recent years they have also been used for special situations in coronary artery bypass grafting. We report on a preliminary, triple center experience with subclavian/axillary artery to coronary artery bypass grafting.

Effects of vasopressin and epinephrine on splanchnic blood flow and renal function during and after cardiopulmonary resuscitation in pigs.

Objective: To compare the effects of vasopressin versus epinephrine on splanchnic blood flow during and after cardiopulmonary resuscitation (CPR), and to evaluate the effects of these vasopressors on renal function in the postresuscitation phase.

Design: Prospective, randomized laboratory investigation using an established porcine CPR model with instrumentation for continuous measurement of splanchnic and renal blood flow.

Setting: University hospital experimental laboratory.

Reactive hyperemia in skin after cardiopulmonary bypass.

Objective: To study reactive hyperemia (RH) using a transcutaneous PO2/PCO2 combination electrode heated to 37 degrees C and tissue reflectance spectrophotometry in patients before and after cardiopulmonary bypass (CPB) to determine whether microcirculatory function of skin is altered.

Design: Prospective study.

Setting: Anesthesiology and critical care unit of a university hospital.

Natriuretic peptides stimulate cyclic guanosine monophosphate production in human saphenous vein and internal mammary artery.

Objective: It has been shown previously that the internal mammary artery releases more cyclic guanosine monophosphate after stimulation with atrial natriuretic peptide than the saphenous vein, and that C-type natriuretic peptide possesses a cyclic guanosine monophosphate stimulating potential on saphenous vein bypass grafts. The present study was undertaken to investigate intracellular content and extracellular release of cyclic guanosine monophosphate, by the internal mammary artery and saphenous vein, after challenge with further members of the natriuretic peptide family.

Methods: Specimens of human internal mammary artery and saphenous vein from 29 patients were cut into segments and stimulated with 10(-6) M concentrations of atrial natriuretic peptide (internal mammary artery n=8, saphenous vein n=10), brain natriuretic peptide (internal mammary artery n=9, saphenous vein n=13), C-type natriuretic peptide (internal mammary artery n=12, saphenous vein n=15), and urodilatin (internal mammary artery n=8, saphenous vein n=12).

Isolated right ventricular assist for postcardiotomy myocardial infarction.

Due to myocardial infarction, profound postcardiotomy right heart failure developed in a 57-year-old man after implantation of an aortic homograft for infective aortic valve endocarditis. Despite maximum medical therapy and intraaortic balloon counterpulsation, signs of endorgan injury developed, and therefore a Thoratec (Pleasanton, CA) right ventricular assist device was implanted. After 17 days of support, myocardial and endorgan function had recovered and the fully mobilized patient was successfully weaned from support and discharged from the hospital.

Beating heart axillocoronary bypass for management of the untouchable ascending aorta in coronary artery bypass grafting.

Objectives: Cannulation and clamping of a severely atherosclerotic ascending aorta during coronary artery bypass grafting (CABG) can lead to cerebral embolization of atheromatous debris and should therefore be avoided whenever possible. A variety of surgical techniques including performance of extraanatomical coronary bypass conduits has been described to solve this problem. We report on a preliminary series of four patients in whom the axillary artery was used as an inflow vessel for venous coronary artery bypass grafts which were performed on the beating heart in order to achieve an aortic no touch concept.

Effect of small-dose dopamine on mesenteric blood flow and renal function in a pig model of cardiopulmonary resuscitation with vasopressin.

Unlabelled: Vasopressin (antidiuretic hormone) seems a promising alternative to epinephrine for cardiopulmonary resuscitation (CPR) in cardiac arrest victims, mediating a pronounced blood flow shift toward vital organs. We evaluated the effects of small-dose dopamine on splanchnic blood flow and renal function after successful resuscitation with this potent vasoconstrictor in an established porcine CPR model. After 4 min of cardiac arrest and 3 min of CPR, animals received 0.

Mucosal tissue oxygenation of the porcine jejunum during normothermic cardiopulmonary bypass.

Cardiopulmonary bypass (CPB) has been associated with intestinal tissue hypoxia, but direct measurements of mucosal oxygenation have not been performed. In anaesthetized pigs, jejunal mucosal oxygen tension and microvascular haemoglobin oxygen saturation were measured by a Clark-type electrode and tissue reflectance spectrophotometry. In pigs, normothermic CPB with systemic oxygen transport equivalent to baseline values was performed.

Anatomical studies concerning technical feasibility of minimally invasive axillocoronary bypass grafting.

Objective: Minimally invasive multiple vessel revascularization has been accomplished using all arterial graft concepts and aortocoronary vein grafts. The aim of the present study was to determine the technical feasibility of minimally invasive axillary artery to coronary artery vein grafting in the human cadaver.

Methods: In seven human cadavers the axillary artery was approached bilaterally via a small incision above the anterior axillary fold.

Single coronary artery bypass grafting--a comparison between minimally invasive 'off pump' techniques and conventional procedures.

Objective: At present, few studies directly comparing minimally invasive and conventional coronary artery bypass grafting are available. The aim of the present study was to evaluate the clinical outcome of the two techniques.

Methods: We retrospectively compared our first consecutive 20 patients undergoing minimally invasive coronary artery single bypass grafting on the beating heart (group I) with 23 consecutive patients receiving single coronary artery bypass via sternotomy using cardiopulmonary bypass and cardioplegia (group II).

Myocardial damage after minimally invasive coronary artery bypass grafting on the beating heart.

Background: In conventional coronary artery bypass grafting, the rate of perioperative myocardial infarction is reported in the 2% to 6% range; however, significantly higher rates are observed if sensitive myocardial marker proteins are used to detect perioperative myocardial damage. For minimally invasive direct coronary artery bypass grafting, few data are available concerning myocardial marker protein release.

Methods: Fifteen consecutive patients (11 male, 4 female; mean age, 59.

Atrial natriuretic peptide-induced release of cyclic guanosine monophosphate by coronary bypass grafts.

Background: Superior long-term patency rates of the internal mammary artery (IMA) versus saphenous vein (SV) after coronary artery bypass grafting are well documented. Higher production rates of vasodilating and platelet-inhibiting mediators (prostacyclin and nitric oxide) by the IMA seem to have a major impact on its long-term durability and resistance to coronary artery graft disease. For the right gastroepiploic artery (RGEA) marked release of protective mediators is reported as well.

Stimulated prostacyclin release by conduits used for coronary artery bypass grafting.

A direct comparison of the three coronary artery bypass conduits internal mammary artery (IMA), right gastroepiploic artery (RGEA), and saphenous vein (SV) concerning arachidonic acid (AA) stimulated release of the vasodilating and platelet inhibiting mediator prostacyclin was the aim of the present study. Pieces of saphenous vein (n = 16), right gastroepiploic artery (n = 8), and internal mammary artery (n = 19) were obtained from patients undergoing coronary artery bypass grafting. After a resting phase of 30 min in HEPES medium arachidonic acid (AA) was added in order to stimulate prostacyclin release.

Inotropic treatment and intestinal mucosal tissue oxygenation in a model of porcine endotoxemia.

Objective: To evaluate the dose-related effects of dopamine, dopexamine, and dobutamine on intestinal mucosal tissue oxygenation following short-time infusion of Escherichia coli lipopolysaccharide, which has previously been shown to decrease mucosal tissue oxygenation by 60% of control values.

Design: Prospective, randomized, unblinded study.

Setting: Animal research laboratory.

Percutaneous venoarterial extracorporeal membrane oxygenation for emergency mechanical circulatory support.

In this retrospective study we report our initial experience with percutaneous venoarterial extracorporeal membrane oxygenation in the emergency treatment of intractable cardiogenic shock or pulseless electrical activity. Between January 1994 and July 1995, percutaneous venoarterial extracorporeal membrane oxygenation was attempted in seven patients (pulseless electrical activity, five patients; cardiogenic shock, two patients). In two of the seven patients, efforts at arterial cannulation resulted in cannula perforation at the level of the iliac artery.

Spinal cord protection in descending and thoracoabdominal aortic surgery--the role of distal perfusion.

The use of distal perfusion in descending thoracic and thoracoabdominal aortic surgery remains a controversial issue. Few mainly retrospective studies which directly compare simple clamping with distal perfusion are available. The aim of the present study was such a comparison in an own series of descending and thoracoabdominal aortic replacement.

[A new cardiac pacemaker stimulation technology (autocapture) allows, with unchanged life expectancy, reduction of generator size by half].

Energy delivery (stimulation amplitude) of a pacemaker should be adjusted to the depolarisation threshold of the heart, which is a nonconstant magnitude. As programming of the stimulation amplitude is time-consuming, many pacemakers are never adjusted to the measured threshold referring to energy delivery. The unnecessary energy loss subsequently reduces the longevity of the implanted devices and remains the weak point of modern pacemakers.

Predictors of short-term survival after helicopter rescue.

The purpose of the present retrospective study was to identify easily obtainable predictors of short-term outcome for emergency victims treated by a physician-staffed helicopter emergency medical system (HEMS). The study was conducted at the HEMS unit 'Christophorus 1' based at Innsbruck, Austria. Outcomes for 2139 patients rescued in primary missions during a 3-year period from 1 January 1989 to 31 December 1991 were included in the study.

Management of profound hypothermia.

Profound hypothermia, defined as a core temperature of less than 28 degrees C, is a life-threatening situation associated with high mortality. Causes of severe hypothermia are prolonged exposure to cold air, water or snow. Initial basic life support and correct decisions to further therapeutic management are crucial for the patient's outcome.

Dopamine-1-receptor stimulation and mucosal tissue oxygenation in the porcine jejunum.

Objective: To evaluate the effects of dopamine-1-receptor stimulation on intestinal mucosal tissue oxygenation.

Design: Prospective, experimental, controlled trial.

Setting: Animal research laboratory.