Laman A. Gray

Preoperative and postoperative comparison of patients with univentricular and biventricular support with the thoratec ventricular assist device as a bridge to cardiac transplantation

OBJECTIVES The goal of this study was to determine whether there are differences in populations of patients with heart failure who require univentricular or biventricular circulatory support. METHODS Two hundred thirteen patients who were in imminent risk of dying before donor heart procurement and who received Thoratec left (LVAD) and right (RVAD) ventricular assist devices at 35 hospitals were divided into three groups: group 1 (n = 74), patients adequately supported with isolated LVADs; group 2 (n = 37), patients initially receiving an LVAD and later requiring an RVAD; and group 3 (n = 102), patients who received biventricular assistance (BiVAD) from the beginning. RESULTS There were no significant differences in any preoperative factors between the two BiVAD groups. In the combined BiVAD groups, pre-VAD cardiac index (BiVAD, 1.4 +/- 0.6 L/min per square meter, vs LVAD, 1.6 +/- 0.6 L/min per square meter) and pulmonary capillary wedge pressure (BiVAD, 27 +/- 8 mm Hg, vs LVAD, 30 +/- 8 mm Hg) were significantly lower than those in the LVAD group, and pre-VAD creatinine levels were significantly higher (BiVAD, 1.9 +/- 1.1 mg/dl, vs LVAD, 1.4 +/- 0.6 mg/dl). In addition, greater proportions of patients in the BiVAD groups required mechanical ventilation before VAD placement (60% vs 35%) and were implanted under emergency conditions than in the LVAD group (22% vs 9%). The survival of patients through heart transplantation was significantly better in patients who had an LVAD (74%) than in those who had BiVADs (58%). However, there were no significant differences in posttransplantation survival through hospital discharge (LVAD, 89%; BiVAD, 81%). CONCLUSION Patients who received LVADs were less severely ill before the operation and consequently were more likely to survive after the operation. As the severity of illness increases, patients are more likely to require biventricular support.

The treatment of acute traumatic rupture of the aorta: A 10 year experience

Forty-three patients with aortic rupture secondardy to blunt trauma have been treated at the University of Michigan within the past 10 years with an overall salvage rate of 70%. The diagnosis should be suspected in anyone who has sustained a high speed decelerating injury, if the chest roentgenograrm shows media-stinal widening, whether or not there is hypertension of the upper extremities; systolic murmur, or external evidence of chest injury. Aortography should be employed to confirm the diagnosis and to determine the site or sites of rupture. Repair of the lesion should be undertaken as soon as possible and takes priority in most instances over associated injuries. Repair in almost all cases can be accomplished safely and quickly using a bypass shunt without the aid of extra-corporeal circulation.

Noninvasive precursor lesions of adenocarcinoma and mixed adenosquamous carcinoma of the cervix uteri

It is postulated that squamous cell carcinoma, adenocarcinoma, and mixed adenosquamous cell carcinoma of the uterine cervix all have a common cell or origin, the subcolumnar reserve cell. The relative frequency with which the various types of carcinoma in situ are seen is in part explained by the ubiquitous nature of squamous metaplasia in the region of the transformation zone in women of reproductive age. It is suggested that squamous metaplasia is the soil on which most squamous carcinomas of the cervix evolve. The relatively low frequency with which adenocarcinoma and adenosquamous carcinoma in situ are encountered may also be dependent on their less accessible location in the endocervix.

Leiomyosarcoma of the uterus

Histologic material from 153 cases of uterine tumors with prior diagnosis or suspicion of sarcoma was reviewed. On the basis of cellularity, pleomorphism, and mitotic counts, 81 smooth muscle tumors were divided into 32 leiomyosarcomas, 31 cellular leiomyomas, 17 bizarre leiomyomas, and one intravascular leiomyoma. Only one case among the 153 was lost to follow‐up. The average yearly instance rate for leiomyosarcoma was 0.67 per 100,000 women 20 years old and older. The incidence was significantly higher in Negroes than in Caucasians. The 5‐year survival rate was 20.7%; however, three of the six 5‐year survivors subsequently died of disease, and one is living with disease. Mitotic counts accurately separate leiomyosarcoma from cellular leiomyoma. No patient with fewer than five mitoses per 10 high‐power field died of disease. The average length of follow‐up was 12 years. In spite of the alarming histologic and cytologic features of bizarre leiomyomas no patient died of disease. Follow‐up averaged 11.2 years.

Intraoperative autotransfusion. Experience in 725 consecutive cases.

Autologous intraoperative transfusion employing the Haemonetics Cell Saver is reported in 725 patients from a general hospital population, of which 75% were cardiovascular patients. The remaining cases included various orthopedic procedures, splenectomy, craniotomy, ectopic pregnancies, Caesarian sections, and exploratory laparotomy. On occasion, this method was utilized in trauma and in pediatric surgery.The product of washed red blood cells gave an average yield of 573 cc per case with an average hematocrit of 55 cc/dl available for autologous infusion. In 100 consecutive open heart procedures operated prior to the Cell Saver period, an average of 1.97 units of bank blood was utilized during operation, as compared with 0.75 units in 100 consecutive cases studied employing the Cell Saver (p < 0.0001). Homologous blood utilization during cardiac surgery declined more than 50% with the use of the Cell Saver. Quality control was monitored scrupulously and included special precautions against air embolism, abnormal coagulation, and sepsis. The overall mortality rate was 2.8%, and in no instance was mortality or morbidity as-cribable to the autologous transfusion.Numerous advantages offered by autotransfusion include prevention of sensitization of the recipient to various antigens in donor erythrocytes, leucocytes, platelets, and plasma, and avoidance of transfusion-transmitted diseases, especially viral hepatitis. Additionally, autologous blood, the only perfectly compatible product, provided immediate availability while conserving blood bank resources. In circumstances in which the intraoperative blood loss exceeded 1000 cc in the adult, its use was observed to be cost-effective. In the present study, autotransfusion proved safe, efficient, and in some instances life saving.

Left ventricular contributions to right ventricular systolic function during LVAD support

BACKGROUND In patients with postcardiotomy low cardiac output syndromes, right ventricular (RV) failure develops in approximately 25% of patients receiving left ventricular (LV) assist device support. Depressed RV function have been attributed to abnormalities of the RV myocardium, excessive load imposed on the RV during systole or diastole, or obstruction to RV inflow. However, recent studies also suggest that LV function may significantly affect RV function through ventricular interdependence. METHODS We reviewed the data showing the importance of systolic ventricular interaction. We then related these observations to the RV response during LV assist device support, and present our ideas regarding the mechanisms responsible for this RV failure. RESULTS Using an electrically isolated right heart preparation, Damiano observed double-peaked waveforms for RV pressure, and pulmonary artery blood flow occurred over a wide range (0 to 300 ms) of pacing intervals between the LV and RV. Numeric analysis indicated that RV systolic pressure and pulmonary artery blood flow were composed of both RV and LV components, with the LV component dominating (63.5% versus 36.5%). CONCLUSIONS The experimental studies indicate a very consistent RV response during LV assist device support: a decrease in RV afterload, increased compliance, and decreased contractility. In normal hearts, the net effect is an increase or no change in cardiac output. With a preexisting pathologic condition, the RV responses is qualitatively the same, but anatomic ventricular interaction is accentuated, leading to a greater decrease in RV contractility. The net effect is a decrease in cardiac output, which may require inotropic or RV mechanical support.

POSTCARDIOTOMY SHOCK - CLINICAL-EVALUATION OF THE BVS-5000 BIVENTRICULAR SUPPORT SYSTEM

This prospective trial evaluated the safety and efficacy of a new pulsatile, temporary ventricular assist device, the BVS 5000. Patients were eligible for treatment if they were hemodynamically unstable despite maximal pharmacologic and intraaortic balloon pump therapy, were free of concomitant complications, and were less than 6 hours from the first attempt to separate from cardiopulmonary bypass. Fifty-five postcardiotomy patients were enrolled; 31 met all selection criteria and the remainder failed to meet criteria (n = 15) or were not successfully supported (n = 9). The BVS 5000 effectively restored hemodynamics: Mean arterial pressure increased (77.1 +/- 8.0 mm Hg on-support versus 50.1 +/- 15.3 mm Hg presupport; p = 0.0001). Cardiac index increased (2.3 +/- 0.3 L.min-1.m-2 on-support versus 1.6 +/- 0.6 L.min-1.m-2 presupport; p = 0.0013). Left ventricular filling pressure decreased (11.9 +/- 4.5 mm Hg on-support versus 23.8 +/- 8.7 mm Hg presupport; p = 0.0030). The most frequent complication was bleeding in 42 patients (76%). Of the patients meeting all criteria, 17 (55%) were weaned from support and 9 (29%) were discharged. Survival was significantly influenced by presupport cardiac arrest events. Survival among patients not experiencing arrest was 47%. Eight patients are long-term survivors and were asymptomatic in New York Heart Association class I or II at 1-year follow-up. The BVS 5000 restored hemodynamics, permitted myocardial recovery, and improved survival in a group of patients who would have otherwise died.

Role of graft flow measurement technique in anastomotic quality assessment in minimally invasive CABG

BACKGROUND Anastomotic quality is currently the critical issue in minimally invasive coronary surgery. Although little is known about its effectiveness, surgeons routinely assess grafts intraoperatively using flow probes. This study was designed to determine whether mean flow and the pattern of flow tracing in internal mammary artery grafts obtained with a transit-time flow probe are reliable indicators of anastomotic quality. METHODS Mongrel dogs (n = 14, 30 to 35 kg) underwent off-pump left, right, or left and right internal mammary artery to left anterior descending artery anastomosis (23 grafts). Moderate to severe degrees of stenosis were created at the anastomosis by an additional suture. Internal mammary artery graft flow was measured before and after the stenosis was created with the left anterior descending artery occluded. Angiography was performed at random postoperatively to validate the degree of stenosis. Mean flow and flow tracing morphology were compared under various degrees of stenosis. RESULTS There were no significant differences in mean graft flow or the morphology of the flow tracing between patent (<15%), mild (<25%), moderate (<50%), and moderately severe (<75%) stenosis. However, mean graft flow decreased (p < 0.05) with severe stenosis (>75%). CONCLUSIONS Although differences in mean graft flow and graft flow morphology were detectable in anastomoses with severe stenosis (>75%), they were indistinguishable in anastomoses with mild (<25%) to moderately severe (<75%) stenosis. Flow measurement techniques are valuable tools intraoperatively, but surgeons should exercise caution in their interpretation.

The AbioCor implantable replacement heart

The AbioCor implantable replacement heart (IRH) is the first available totally implantable artificial heart. We recently initiated a multicenter trial of this device in patients with severe, irreversible biventricular failure. Patients who were not candidates for other therapies, including transplantation, were evaluated. All candidates were adults with inotrope-dependent biventricular failure, whose 30-day predicted mortality was higher than 70%. A three-dimensional computerized fit study predicted fit of the AbioCor thoracic unit in all recipients. At operation, the internal battery controller and transcutaneous energy transfer unit were placed. The AbioCor thoracic unit was placed in an orthotopic position after incision of the ventricals. There were 2 intraoperative deaths (due to intraoperative bleeding or aprotinin reaction). Four late deaths were recorded, 1 from multisystem organ failure and 3 cerebrovascular accidents. Autopsy revealed thrombus on the atrial struts of the 3 patients with cerebrovascular accident. Blood pumps and valves were clean on all patients. Significant morbidity was observed, primarily related to preexisting severity of illness. However, 3 patients recovered to the point of being able to take multiple trips outside of the hospital. Two patients were discharged from the hospital, with 1 patient being discharged home for more than 7 months. No significant device malfunctions or multi-system organ failure device-related infections were noted. The AbioCor IRH may be effective therapy for patients with end-stage heart failure. Many milestones have been achieved in the initial trial in humans, including the successful discharge of a patient to home and no significant device malfunctions. The occurrence of stroke is likely related to the presence of thrombus on the atrial struts and may be decreased as these atrial struts have been removed for future clinical implants.

Predictors of quality of life following cardiac transplantation.

Abstract Eleven heart transplant patients were evaluated psychiatrically before the operation, with possible mental disorder diagnosed according to DSM-III. Data were recorded for the medical course until 12 months after the operation, and the patients completed a scored quality of life questionnaire at nine to 15 months after the surgery. The results showed that the presence of a personality disorder before the operation and a poorer medical course after surgery predicted a poorer quality of life. The results were interpreted within a framework suggesting a significant role for noncompliance with the medical regimen by patients with personality disorders.