Quantitative investigation of cardiomyocyte hypertrophy and myocardial fibrosis over 6 years after cardiac transplantation.

Objectives: This study was performed to determine the degree and time course over 6 years of cardiomyocyte hypertrophy and myocardial fibrosis of the cardiac allograft in transplanted patients.

Background: Diastolic dysfunction and to a certain extent systolic dysfunction are common cardiac findings after heart transplantation. The development of posttransplant cardiomyocyte hypertrophy and myocardial fibrosis likely contributes to these derangements.

Effects of hypoproteinemia-induced myocardial edema on left ventricular function.

In previous studies, we observed left ventricular (LV) systolic and diastolic dysfunction in association with interstitial myocardial edema (IME) induced by either coronary venous hypertension (CVH) or lymphatic obstruction. In the present study, we examined the effects of myocardial edema induced by acute hypoproteinemia (HP) on LV systolic and diastolic function. We also combined the methods of HP and CVH (HP-CVH) to determine their combined effects on LV function and myocardial water content (MWC).

Posttransplantation lymphoproliferative disorder in cardiac transplant allografts.

Posttransplantation lymphoproliferative disorder occurs in 1.5% to 13% of heart transplant recipients and rarely involves the allograft. We report a case of posttransplantation lymphoproliferative disorder restricted to the mitral valve in a heart transplant recipient.

Mechanical workload-myocardial water content relationship in isolated rat hearts.

We tested the hypothesis that the mechanical workload of the heart inversely determines the rate of myocardial edema formation in an isolated, perfused rat heart preparation. Heart rate (HR) was varied in three groups by pacing at 125 (HR125), 250 (HR250), or 350 beats/min (HR350). Left ventricular pressure (LVP) was varied in two additional groups by pacing at 250 beats/min and with the addition of either epinephrine (Epi) or propranolol (Pro) to the perfusate.

Impairment of left ventricular function by acute cardiac lymphatic obstruction.

Objectives: We performed the following study to define the effects of acute cardiac lymphatic obstruction on left ventricular (LV) systolic and diastolic function.

Methods: Cardiac lymphatic obstruction was created in 8 pentobarbital-anesthetized dogs by identifying (Evans blue) and ligating the right and left epicardial lymphatics, the afferent and efferent lymphatics associated with the pretrachael and cardiac lymph nodes, and the thoracic duct. Left ventricular function was assessed by analysis of micromanometer-conductance catheter-derived LV pressure-volume relationships.

A comparison of isoflurane versus fentanyl as primary anesthetics for mitral valve surgery.

We conducted a randomize study of fentanyl compared to isoflurane anesthesia in patients with pulmonary hypertension undergoing mitral valve surgery. Patients were premedicated and randomly assigned to one of two groups: 21 patients had anesthesia induced with thiopental and maintained with isoflurane; 23 patients had anesthesia induced with a fentanyl bolus and maintained with a fentanyl infusion. Adjustments of fentanyl infusion and isoflurane concentration, as well as fentanyl boluses and vasoactive/positive inotropic medication, were administered to maintain preoperative arterial blood pressure.

Acute transient coronary sinus hypertension impairs left ventricular function and induces myocardial edema.

This study was performed to evaluate the direct and indirect effects of acute coronary sinus hypertension (CSH) on systolic and diastolic left ventricular (LV) function. Coronary sinus pressure was elevated to 25 mmHg for 3 h in eight pentobarbital-anesthetized dogs and then relieved. LV contractility was assessed by preload recruitable stroke work (PRSW) and end-systolic elastance (Ees).

Effects of acid aspiration-induced lung injury on left ventricular function.

Background: Acid aspiration-induced acute lung injury (AALI) leads to myocardial leukosequestration and edema in rats and hemodynamic depression in dogs, but the effects of AALI on left ventricular (LV) function have not been carefully studied.

Methods: We examined the effects of 0.1 N HCl administration into the lung on LV function, leukosequestration, and edema in pentobarbital-anesthetized, atropinized (n = 8), or autonomically blocked (n = 7) dogs.

Left atrial volumes and function in orthotopic cardiac transplantation.

Early ventricular filling and therefore passive left atrial emptying may be impaired in patients with cardiac transplantation. As a result, left atrial function may be an important factor in maintaining stroke volume in recipients of orthotopic cardiac transplants. Left atrial volumes maximal (mitral valve opening), minimal (mitral valve closure), and onset of atrial systole (P wave on electrocardiogram) were determined by echocardiography using the biplane area-length method in 12 patients after cardiac transplantation and 12 control subjects.

Neuropsychological function in patients with end-stage heart failure before and after cardiac transplantation.

This study was performed to examine cognitive function in patients with end-stage heart failure, to identify possible cardiovascular factors associated with cognitive function, and to evaluate changes in cognitive function in a subgroup of patients who received heart transplantation. An extensive battery of neuropsychological tests were given to 62 patients with end-stage cardiac failure as part of their evaluation for cardiac transplantation. Most patients were consecutive referrals, not selected because of cognitive complaints.

Acute lung injury isolated to an in situ lung preparation causes sustained reflex cardiovascular depression in dogs.

We tested the hypothesis that acute lung injury (ALI) isolated to a perfused in situ left lung preparation results in sustained reflex cardiovascular depression. Phorbol myristate acetate (PMA), an agent that activates neutrophils, administered into the isolated lung preparation of chloralose-anesthetized dogs resulted in ALI, as assessed by wet-to-dry weight ratios and histopathology, and significant decreases in heart rate (43%), mean arterial pressure (27%), aortic blood flow (29%) and maximum rate of change in left ventricular pressure (30%). Significant reflex effects occurred by 20 min after PMA administration and were sustained for 40 min (n = 7).

Vagal innervation influences the whole body oxygen consumption-delivery relationship in the dog.

Vagotomy alters regional blood flow distribution by interrupting the tonic central inhibitory effect of cardiopulmonary vagal afferent nerves on sympathetic outflow predominantly to the renal, splanchnic, and cutaneous circulations. We hypothesized that the alteration of blood flow distribution by vagotomy would lead to disruption of the oxygen consumption-oxygen delivery relationship (VO2/DO2), increase critical DO2 (DO2Crit), and decrease whole-body oxygen extraction ratio (O2ER). Nineteen chloralose-anesthetized, paralyzed, splenectomized dogs were submitted to either bilateral vagosympathectomy (n = 7), bilateral vagotomy (n = 6), or sham denervation (n = 6) following baseline cardiorespiratory parameter measurement.

Timing of recipient atrial contraction: a major determinant of transmitral diastolic flow in orthotopic cardiac transplantation.

The effect of recipient left atrial contraction on diastolic transmitral flow was studied in eight asymptomatic heart transplant patients (seven men and one woman, mean age 51.8 +/- 9.7 years) with normal left ventricular systolic function.

Catheter-induced pulmonary artery rupture in the setting of cardiopulmonary bypass.

Pulmonary artery rupture is an infrequent complication of flow-directed catheters. Because cardiopulmonary bypass offers an opportunity for control of gas exchange and hemorrhage, pulmonary artery rupture in this setting is different from that occurring in the intensive care unit and catheterization laboratory. A collective review of 30 published cases was conducted.

Intraoperative and postoperative effects of vancomycin administration in cardiac surgery patients: a prospective, double-blind, randomized trial.

Objectives: In response to an increased frequency of Staphylococcus epidermidis infections in postoperative cardiac surgery patients, antibiotic prophylaxis was changed to include both vancomycin and cefazolin pre- and intraoperatively. Subsequent to the addition of vancomycin prophylaxis, clinical impression and retrospective analysis supported a correlation between vancomycin administration and post-cardiopulmonary bypass norepinephrine use.

Design: A prospective, double-blind, randomized study.

The significance and prevention of air emboli with the total artificial heart.

Embolism remains a significant complication of the total artificial heart (TAH). The ineffectual deairing of the TAH can allow embolization of the retained air. The standard needle aspiration of TAH air (Group A) was compared with a new protocol (Group B) that included standard needle TAH aspiration plus simultaneous pumping of the TAH against an occluded ascending aorta and main pulmonary artery with vacuum applied to a needle in the proximal aorta and pulmonary artery.

Effects of successful cardiac transplantation on plasma endothelin.

After cardiac transplantation, cyclosporine-treated patients exhibit a high incidence of systemic hypertension, the mechanism of which is not known. Endothelin, a potent vasoconstrictor peptide of endothelial origin, may be activated by cyclosporine-induced endothelial injury and therefore may mediate post-transplant hypertension. In the present study, we tested whether immunoreactive endothelin-1 could be detected by radioimmunoassay in the plasma of cardiac transplant recipients and if levels correlated with hemodynamic characteristics, cyclosporine level, or renal function as assessed by serum creatinine.

A limited axillary thoracotomy as primary treatment for recurrent spontaneous pneumothorax.

Recurrent spontaneous pneumothorax often requires surgical treatment following variable periods of chest tube therapy. A limited axillary thoracotomy provides sufficient exposure to isolate or excise pulmonary blebs and perform a pleurodesis. Prompt use of this surgical approach in lieu of the initial placement of a thoracostomy tube avoids prolonged hospitalization and a significant failure rate of thoracostomy tubes to resolve this problem.

Remnant atrial function in human and animal recipients of a total artificial heart.

The native atria remains intact after total artificial heart (TAH) implantation. The electrical activity of the recipient's atria can be recorded from wires placed during TAH implantation. Regulating TAH heart rate by coupling it with native atrial activity has the potential for a more physiologically responsive TAH.

Comparative study of cefazolin, cefamandole, and vancomycin for surgical prophylaxis in cardiac and vascular operations. A double-blind randomized trial.

Three-hundred twenty-one adults undergoing cardiac or major vascular operations were randomized to receive intravenous cefazolin, cefamandole, or vancomycin for prophylaxis against surgical infection in a double-blind trial. All three regimens provided therapeutic blood levels throughout operation in patients studied undergoing cardiopulmonary bypass. The prevalence of surgical wound infection was lowest with vancomycin (4 infections [3.

Permanent pacing in heart transplant recipients: underlying causes and long-term results.

Although the majority of heart transplant recipients have a satisfactory heart rate, a substantial number require a permanent pacemaker. In 7 of 46 heart transplant patients at our institution symptomatic bradycardia developed, necessitating implantation of a transvenous pacemaker. The average time from heart transplantation to pacer insertion was 25 days.

Dobutamine increases cardiac output of the total artificial heart. Implications for vascular contribution of inotropic agents to augmented ventricular function.

Background: The synthetic catecholamine dobutamine increases stroke volume in normal subjects and in patients with congestive heart failure. In addition to its direct influence on myocardial contractility, dobutamine may significantly modulate vascular tone because of its alpha- and beta-adrenergic agonist activity.

Methods And Results: To test the hypothesis that such vasoactive properties significantly contribute to the improved ventricular performance noted with this agent, hemodynamic parameters were measured during stepped ascension infusion of dobutamine in a model that is insensitive to positive inotropic stimulation.

Preserved atrial natriuretic peptide secretory function after cardiac transplantation.

The purpose of this investigation was to determine whether atrial natriuretic peptide (ANP) secretory function is preserved after cardiac transplantation. Thirteen hemodynamically stable outpatients performed supine exercise on a bicycle an average of 7 months after orthotopic cardiac transplantation. Right atrial pressure increased 2.

Adenine nucleotide content in cold preserved human donor hearts and subsequent cardiac performance after orthotopic heart transplantation.

Myocardial high-energy phosphate content has been used as a parameter to evaluate the adequacy of donor organ preservation. The purpose of this study was to assess current techniques of preservation by measuring high-energy phosphates in cold preserved (4 degrees C) human donor hearts. Endomyocardial biopsy samples of the donor heart right ventricular septum (n = 24) were compared with samples from patients with normal cardiac function evaluated before chemotherapy (n = 12).