Diagnosis and successful management of septal myocardial abscess: a complication of bacterial endocarditis.

A case of acute enterococcal aortic valve endocarditis is presented in which the complication of a septal myocardial abscess was diagnosed clinically and successfully treated surgically. This represents the first instant, to our knowledge, in which the preoperative diagnosis of a myocardial abscess served as the indication for emergency cardiac surgical intervention in active endocarditis with successful outcome. The diagnostic parameters permitting clinical recognition of a myocardial abscess include the development of advancing degrees of atrioventricular and bundle branch block, and the finding of pericarditis or pericardial effusion in aortic valvular infections. Two additional findings were noted in the present case: echocardiographic evidence of septal thickening, and loss of septal Q waves on the electrocardiogram. Since myocardial abscesses do not respond to medical therapy, continuous electrocardiographic monitoring and frequent echocardiographic determinations are recommended in cases of active aortic valve endocarditis to permit early diagnosis and surgical management of this complication.

Reduction of unexpected, life-threatening events in postoperative cardiac surgical patients; the role of computerized surveillance.

With increasing use of computerized surveillance (CS) in critical care, a key question is whether it favorably influences clinical outcome. Knowing that two intensive care unit beds would soon have CS capability, we embarked on an uninterrupted prospective study in which the incidence of sudden, unexpected life-threatening events (SULTE) was compared in post-open heart surgery patients whose subsystem performances were evaluated by conventional methods (CM) as opposed to those who would be followed by CS involving automatic acquisition and generation of 30 cardio-respiratory variables. We evaluated 211 patients, 91 with CM and 120 by CS. Since CS availability was limited, sicker patients were given priority for the two CS beds. Despite the obvious bias in favor of CM, there was a statistically significant reduction (P less than 0.001) in the incidence of SULTE in those patients followed by CS (1 of 120 patients: 0.8%; no SULTE-related deaths) in comparison to the CM patients (11 of 91 patients: 12%; two SULTE-related deaths.) The data suggest that computerized surveillance can play a role in reducing morbidity and possibly mortality in postoperative cardiac surgical patients.

Left heart assist device: early clinical experiences with management of postperfusion low cardiac output.

Low cardiac output is a continuing cause of mortality after intracardiac operation in patients coming to surgery with advanced myocardial dysfunction. A simple method using a left heart assist device (LHAD) after open heart surgery to manage low cardiac output resistant to all adjuvant therapy is described. Except for the special cannulas, all equipment necessary for the LHAD is available in any unit performing open-heart surgery. Fifteen patients who could not be separated from conventional cardiopulmonary bypass underwent postoperative support with the LHAD (up to 501 hours). Ten patients were weaned from the device and 6 were dismissed from the hospital. Four patients remain alive, the longest period after operation being 24 months. A major asset of the LHAD is that thoracic reentry is not required at termination of LHAD support, since their design permits the cannulas to remain permanently in situ. This is thought to be an important concept, since critically ill patients requiring support are precisely those in whom added risk would be imposed by a second operation.

Temporary mechanical support of left ventricular failure following open heart surgery.

Patients coming to open heart surgery with advanced cardiac dysfunction may require mechanical cardiac support to avoid life-threatening low cardiac output in the postoperative period. 15 patients who could not be withdrawn from cardiopulmonary bypass because of low cardiac output were supported with a left heart bypass system (left atrium to ascending aorta). Ten were ultimately separated from the device, 6 were dismissed from the hospital and 4 remain well (the longest 2.6 years postoperative). A major asset of the device is that thoracic reentry is not required when support is discontinued.

Role of the Hancock "stabilized glutaraldehyde process" bioprosthesis in the management of mitral valve disease.

The low mortality of isolated mitral valve (MV) replacement permits attention to be focused on those valve-related factors which affect the quality of life after operation. Comparison of a number of MV prostheses indicates that all perform satisfactorily from the hemodynamic standpoint. An asset of the "stabilized glutaraldehyde process" (SGP) Hancock bioprosthesis (H-B) is the significantly lower incidence of thromboembolism encountered in patients who have not been permanently anticoagulated. While additional time is required before meaningful durability comparisons can be made, the absence of valve failure and the low incidence of tissue dysfunction in H-B over 6 1/2 years is encouraging. Although the ideal device for replacing the MV is not yet available, the Hancock SGP bioprostheses represent the best compromise of available choices.

Postcardiotomy low cardiac output clinical experience with a left heart assist device.

Fifteen patients with advanced heart disease who could not be withdrawn from cardiopulmonary bypass (CPBP) because of low cardiac output were supported with a left heart assist device (LHAD). The system (left atrium to ascending aorta bypass of left ventricle) was not employed until all other measures had failed to allow separation from CPBP, including intraaortic balloon counterpulsation whenever possible. In this experience no attempt was made to totally bypass the left ventricle (LV). Rather, LHAD flow rate was adjusted so that the combined output of the LHAD and depressed LV achieved satisfactory levels of systemic blood flow at acceptable LV filling pressures. With improved cardiac performance patients were separated from the LHAD without need for thoracic reentry. Of the 15 patients having LHAD support (longest 21 days), 10 could be separated from the device and six were dismissed from the hospital. Four remain well, the longest 1.6 years postoperatively. Patients requiring 3 days or less of circulatory assistance had a more favorable prognosis than those needing more extended periods of support.

Circulatory support with a left-heart assist device after intracardiac operation: design concepts and management techniques.

A simple left-heart assist device was developed to reduce left ventricular preload while simultaneously increasing total systemic blood flow. It consists of special cannulas connected to a simple extracorporeal tubing loop and roller pump, designed to permit bypass of as much as 5 liters of blood per minute from left atrium to ascending aorta. Employed in 15 patients with advanced heart disease who were in low cardiac output following repair, the system was proven effective. An asset of the device is the ability to subsequently separate the patient from the device without need to reenter the thorax or abdomen.

Use of a left heart assist device after intracardiac surgery: technique and clinical experience.

A left heart assist device (LHAD) has been employed in 14 patients. All had advanced heart disease and were in low cardiac output after repair, such that they could not be separated from cardiopulmonary bypass despite prolonged support and adjuvant therapy, including drugs, pacing, and use of intraaortic balloon counterpulsation whenever possible. Apart from special cannulas, the equipment necessary for the LHAD is widely available. An asset of the system (left atrial-ascending aorta bypass of the left ventricle) is that it may be terminated without reentering the thorax to remove the cannulas. This is accomplished with precisely fitting obturators that obliterate the cannula lumens and allow the tubes to be permanently implanted. This concept is believed important since critically ill patients requiring support are precisely those in whom added risk would be imposed by a second operation. Of the 14 patients who have had intraoperative and postoperative support (up to 6.8 days), 9 were weaned from the device and 6 were dismissed from the hospital. Four patients remain alive and are improved, the longest at 22 months since operation. The favorable performance of the LHAD suggests that it may prove useful either when intraaortic balloon counterpulsation cannot be successfully deployed or when it has failed to achieve hemodynamic stability.

The use of vein allografts as sidearms for intraaortic balloon insertion.

Femoral artery cannulation for intraaortic balloon counterpulsation may be attended by difficulties due to changes in the vessel wall and the inherent stiffness of Dacron grafts. A substitute technique utilizing venous allografts is described. The advantages are enumerated and are related to allograft pliability. Fifty-nine such procedures have been done without related complications.

Early clinical experiences with a heart assist device.

A method of left heart (left atrium-aorta) support after open heart surgery is described. Thoracic reentry is not required when support is terminated. The system has been employed in 10 patients, 4 of whom are long-term survivors.