Midazolam-sufentanil vs sufentanil-enflurane for induction of anaesthesia for CABG surgery.

Purpose: To compare the effects of midazolam-sufentanil (Group I) and sufentanil-enflurane (Group II) anaesthesia on myocardial oxygenation and metabolism in patients with preserved ventricular function undergoing CABG surgery.

Methods: Patients randomized to Group I (n = 16) received midazolam 0.3 mg.

Preconditioning prevents myocardial stunning after cardiac transplantation.

Background: Preconditioning has been shown to reduce myocardial stunning after reversible global ischemia. To determine whether preconditioning improves functional recovery after cardiac transplantation, 16 sheep were randomly assigned to a preconditioning protocol or to a control group.

Methods: Preconditioning was achieved with 5 minutes of global ischemia followed by 10 minutes of reperfusion.

Midterm results with the Sorin Monostrut heart valve prosthesis.

Objective: To monitor the hematological and clinical sequelae of a single tilting disc cardiac valve prosthesis.

Design: Prospective nonrandomized trial.

Setting: University teaching hospital.

Delayed stimulation of the latissimus dorsi may result in disuse atrophy.

Background: The latissimus dorsi is usually left unstimulated for 2 weeks after cardiomyoplasty to allow the muscle to recover from the loss of the collateral circulation. To determine whether the 2-week delay may cause muscle atrophy, we randomized 15 mongrel dogs to a control group or a disuse atrophy group.

Methods: The collateral circulation to the latissimus dorsi was ligated in all animals before cardiomyoplasty to reduce the risk of ischemic injury to the muscle during mobilization.

Preconditioning during warm blood cardioplegia.

Objective: Preconditioning describes the cardioprotective effects of multiple brief episodes of warm ischemia. The purpose of the study was to determine whether warm ischemia, during the intermittent delivery of warm blood cardioplegia, would induce preconditioning during cardioplegia arrest.

Methods: Dogs, 15, were randomized to a preconditioning protocol or to serve as controls.

The use of low-dose aprotinin, epsilon-aminocaproic acid or tranexamic acid for prevention of mediastinal bleeding in patients receiving aspirin before coronary artery bypass operations.

Patients undergoing primary myocardial revascularization were randomized to one of three drug regimens (low-dose aprotinin, epsilon-aminocaproic Acid or tranexamic Acid) to determine which drug regimen would most effectively reduce post-operative bleeding and the need for blood products. All patients had received 325 mg of aspirin within 48 h before operation. All three drug regimens reduced the requirements for blood products and postoperative bleeding after coronary artery bypass operations.

Randomized trial comparing intermittent antegrade warm blood cardioplegia with multidose cold blood cardioplegia for coronary artery bypass.

Forty patients were randomized to receive antegrade multidose warm (WBC) or cold blood cardioplegia (CBC) during coronary artery bypass. Cardioplegia was infused at a predetermined dose every 10 min during cardioplegia arrest and core temperature was maintained at 37 degrees C in both groups during extracorporeal circulation. Patient profiles were similar in the two groups.

Evidence of type 2 herpes simplex infection in human coronary arteries at the time of coronary artery bypass surgery.

Objective: To examine histologically biopsies from the coronary arteries of patients undergoing coronary artery bypass grafting (CABG) for evidence of herpes simplex virus type 1 (HSV-1) and type 2 (HSV-2) antigen and to correlate the incidence with pathological and clinical data.

Design: Sequential patients undergoing CABG in whom adequate tissue could be obtained for histology.

Setting: University teaching hospital.

Medtronic Intact porcine bioprosthesis: clinical performance to seven years.

The clinical performance of the Medtronic Intact porcine bioprosthesis was evaluated in 1,084 patients (mean age 66.4 years, range 9 to 91 years) who had a total of 1,099 implantations between 1985 and 1992, inclusive. There were 709 aortic valve replacements, 297 mitral valve replacements, and 80 multiple valve replacements.

Effect of cardiomyoplasty on systolic and diastolic function.

Unlabelled: Although cardiomyoplasty has become a recognized treatment for end-stage heart failure, the effects of this procedure on systolic and diastolic function are still unclear. To determine the effects of paced and non-paced latissimus dorsi cardiomyoplasty on systolic and diastolic function, the maximal elastance of the left ventricle (Emax), stroke volume, preload recruitable stroke work and diastolic compliance were measured in an experimental heart failure model. Collateral blood vessels to the latissimus dorsi were ligated 2 weeks before cardiomyoplasty in order to reduce the risk of ischemic injury.

Casualties treated during MILCON 92: relevance to training of militia medical personnel.

A brigade field hospital provided the medical support for 2,600 troops during MILCON 92 (Militia Concentration 1992). During the exercise, 6.5% of the military personnel required treatment.

Fracture of the internal lumen of a Datascope Percor Stat-DL Balloon, resulting in stroke.

Intraaortic balloon counterpulsation was used to wean a 71-year-old man from cardiopulmonary bypass. Thirty-six hours after insertion, the internal lumen of the Datascope balloon fractured, releasing an unknown quantity of helium into the patient's circulation. Left-sided hemiparesis developed, secondary to a right hemispheric infarction.

Effect of intermittent delivery of warm blood cardioplegia on myocardial recovery.

Continuous warm blood cardioplegia is often temporarily interrupted during coronary artery operations to provide the surgeon with a bloodless operating field. To determine the effects of intermittent warm ischemia on myocardial recovery, we randomized 15 adult mongrel dogs to receive either multidose cold or warm blood cardioplegia during a 90-minute arrest. Myocardial metabolic and functional recovery was assessed before clamping of the aorta and after 30 and 60 minutes of reperfusion.

Influence of systemic hypothermia on systolic and diastolic functional recovery after continuous warm antegrade blood cardioplegia.

Experimental observations in our laboratory indicate that myocardial recovery is similar following warm or cold antegrade blood cardioplegia when the core temperature is maintained at 37 degrees C. To determine the effects of hypothermia on myocardial recovery, 15 adult mongrel dogs were randomized to normothermic or hypothermic bypass (28 degrees C) during 60 min of continuous warm antegrade blood cardioplegia. The hypothermic group was rewarmed after releasing the aortic cross-clamp and bypass was discontinued at 30 min in both groups.

Myocardial metabolic and hemodynamic changes during propofol anesthesia for cardiac surgery in patients with reduced ventricular function.

This study examined the hypothesis that the use of propofol for induction and maintenance of anesthesia in patients with reduced ejection fraction (< 0.5) undergoing coronary artery revascularization would not be associated with a greater degree or incidence of myocardial ischemia as compared to patients receiving a moderate dose sufentanil-enflurane anesthetic technique. Two groups of patients were assigned randomly to receive one of two propofol anesthetic regimes.

Mycobacterium avium-intracellulare endocarditis causing rupture: replacement and repair with aortic homograft.

Aortic valve endocarditis with extension to the tricuspid annulus and ventricular septum in an intravenous drug abuser - with Mycobacterium avium-intracellulare identified as the offending organism - forms the basis of this report. The aortic root and ventricular septal defect were successfully repaired using an aortic cryopreserved homograft. This case is of particular interest because M avium-intracellulare has not been recognized as a cause of endocarditis.

Morphometric analysis on myocardial injury related to the use of high volume potassium cardioplegic solution during ischemic arrest.

We correlated the effects of high volumes of K+ cardioplegic solution on myocardial structure and function in 16 dogs following open-heart surgery. Eight animals received high volume potassium cardioplegic solution (25 cc/kg body weight, every 30 min) during 90 min of ischemic arrest (HVK-C group). The others received sufficient cardioplegic solution to maintain complete electrical arrest as defined by voltage monitoring criteria (VM group).

Myocardial oxygen consumption and lactate production during antegrade warm blood cardioplegia.

Unlabelled: Continuous warm blood cardioplegia has recently been recommended as an alternative to multidose cold blood cardioplegia for myocardial protection during coronary bypass operations. Cardioplegia may have to be interrupted in order to provide a bloodless operating field during coronary anastomosis. To determine the effects of ischemia at normothermia on myocardial oxygen consumption and lactate production we randomized 17 dogs to receive either warm blood cardioplegia (37 degrees C) or cold blood cardioplegia combined with systemic and topical cooling.

Effect of aspirin on intimal proliferation and tissue cholesterol in long-term experimental bypass grafts.

Unlabelled: A single daily dose of aspirin (ASA) reduces the incidence of early graft thrombosis after coronary bypass operations. Recent data indicate that aspirin may not prevent intimal proliferation and cholesterol uptake in experimental bypass grafts which suggests that aspirin may not improve long-term graft patency. To further clarify the effects of aspirin on intimal proliferation and cholesterol metabolism, we performed femoral interposition vein grafts in 12 dogs receiving a 2% cholesterol diet.

A comparison of the myocardial metabolic and haemodynamic changes produced by propofol-sufentanil and enflurane-sufentanil anaesthesia for patients having coronary artery bypass graft surgery.

The purpose of this study was to compare propofol-sufentanil with enflurane-sufentanil anaesthesia for patients undergoing elective coronary artery bypass graft (CABG) surgery with respect to changes in (1) haemodynamic variables; (2) myocardial blood flow and metabolism; (3) serum cortisol, triglyceride, lipoprotein concentrations and liver function; and (4) recovery characteristics. Forty-seven patients with preserved ventricular function (ejection fraction greater than 40%, left ventricular end diastolic pressure less than or equal to 16 mmHg) were studied. Patients in Group A (n = 24) received sufentanil 0.

Effect of aspirin on intimal hyperplasia and cholesterol uptake in experimental bypass grafts.

The effects of aspirin on intimal and medial smooth muscle cell proliferation and cholesterol uptake in experimental bypass grafts were examined in a hypercholesterolemic canine model. Ten animals receiving a 2% cholesterol diet served as controls, while a further 10 animals received the same diet and 160 mg aspirin daily. Segments of external jugular vein were implanted between bilaterally divided femoral arteries.

Inaccuracy of serum lipid measurements after open heart operations.

Serum lipids were measured in 20 patients before and within one week following coronary artery bypass. The total serum cholesterol was decreased by 45%, while low density lipoprotein cholesterol and high density lipoprotein cholesterol were reduced by 50% and 30%, respectively. Hemodilution for cardiopulmonary bypass temporarily lowers serum lipids, indicating that screening procedures for hyperlipidemia should not be performed immediately following cardiac operations.

Oxygenated cardioplegia ameliorates the adverse effects of small amplitude electrical recording of activity on myocardial metabolic and functional recovery.

Unlabelled: Small amplitude electrical activity has been recorded from the myocardium during cardioplegic arrest in the absence of electromechanical activity. The presence of persistent electrical activity has been associated with impaired myocardial metabolic and functional recovery. To determine whether or not oxygenated cardioplegia would provide sufficient oxygen to support the increased metabolic activity associated with persistent electrical activity during cardioplegic arrest, we randomized 14 adult mongrel dogs to receive either non-oxygenated or oxygenated cardioplegia during 90 min of ischaemia.

Recurrent atrial arrhythmias following treatment for postoperative atrial fibrillation after coronary bypass operations.

Ambulatory Holter monitoring was performed in 58 patients during the early convalescence after myocardial revascularization in order to determine the incidence of recurrent atrial arrhythmias following treatment for postoperative atrial fibrillation. Fifteen patients who had undergone coronary bypass and had not developed spontaneous atrial fibrillation following operation served as the controls (group 1). The remaining patients developed spontaneous symptomatic atrial fibrillation after coronary bypass that required digitalization for rate control.