Hypotension, acidosis, and vasodilatation syndrome post-heart transplant: prognostic variables and outcomes.

BACKGROUND: In recent years a syndrome characterized by hypotension, acidosis, and vasodilatation, which we have designated HAV syndrome, has been reported to occur more frequently after heart transplantation (HT), but its pathogenesis is unknown. METHODS: We analyzed consecutive patients undergoing HT between January 1994 and June 1998 (aged 50 +/- 8 years; 87% male; 40% African American; ischemia time, 190 +/- 20 minutes; given triple immunosuppression without anti-lymphocyte antibodies) in 2 groups: 38 (54%) who developed HAV (systemic vascular resistance < or = 800 dines x sec x cm(-5) and serum bicarbonate < or = 20 mEq/liter) and 32 (46%) who did not. To identify causes of HAV, we compared 113 pre-HT donor and recipient variables, 28 peri-HT variables, and 46 post-HT variables between groups. We used Mann-Whitney, Fisher exact, and chi-squared tests to compare variables and to determine significance. RESULTS: Univariate analysis showed that HAV patients had significantly greater recipient and donor weight (p = 0.000007 and 0.0017, respectively), longer ischemia times (p = 0.0052), pre-HT use of beta-blockers (p = 0.009), and longer waiting times for HT (p = 0.018). African-American patients had less HAV than Caucasians (p = 0.047). Patients with pre-HT mechanical circulatory assistance had less HAV than pharmacologically treated patients (p = 0.014). Multivariate analysis showed that recipient (p = 0.0004) and donor weight (p = 0.0394) and ischemia time (p = 0.0015) independently predicted HAV and correlated with HAV severity. Deaths at < or =30 days of HT occurred more in patients with (33%) than in those without (15%) HAV. CONCLUSIONS: (1) Hypotension, acidosis, and vasodilatation after HT are associated with high mortality. (2) Recipient and donor weights and ischemia time are independent risk factors for HAV. (3) Pre-HT mechanical circulatory assistance and African-American race confer protection against HAV. (4) Because HAV risk factors can be altered, prevention may be possible. Further study is needed to identify the cellular and humoral mediators of HAV.

A multicenter, randomized, controlled trial of Celsior for flush and hypothermic storage of cardiac allografts.

BACKGROUND: A multicenter, randomized, controlled, open-label trial was conducted to evaluate the safety and efficacy of Celsior when used for flush and hypothermic storage of donor hearts before transplantation. METHODS: Heart transplant recipients were randomized to one of two treatment groups in which donor hearts were flushed and stored in either Celsior or conventional preservation solution(s) (control). Study subjects were followed for 30 days after transplantation. RESULTS: A total of 131 heart transplant recipients were enrolled (Celsior, n = 64; control, n = 67). The treatment groups were evenly distributed in donor and recipient base line characteristics. Graft loss rate was lower in the Celsior group on day 7 (3% versus 9%) and on day 30 (6% versus 13%), but the difference was not statistically significant based on 95% confidence interval analysis. No significant difference was measured between the Celsior and control groups in 7-day patient survival (97% versus 94%) and the proportion of patients with one or more adverse events (Celsior, 88%; control 87%) or serious adverse events (Celsior, 38%; control, 46%). Significantly fewer patients in the Celsior group developed at least one cardiac-related serious adverse event (13% versus 25%). CONCLUSIONS: Celsior was demonstrated to be as safe and effective as conventional solutions for flush and cold storage of cardiac allografts before transplantation.

Improvement in quality of life outcomes 2 weeks after left ventricular assist device implantation.

BACKGROUND: The successful use of left ventricular assist devices (LVADs) as a bridge to heart transplantation has prompted our examination of quality of life (QOL) outcomes. The purposes of this study are to describe QOL in patients 1 to 2 weeks after LVAD implantation and to compare QOL in a smaller cohort of patients from before to 1 to 2 weeks after surgery. METHODS: Data were collected from a convenience sample of 81 patients who completed booklets of questionnaires that measure domains of QOL 1 to 2 weeks after LVAD insertion and from 30 of 81 patients who completed booklets at both the pre-implantation and post-implantation periods. Patients completed booklets of 6 to 8 self-reporting instruments, with acceptable reliability and validity. Data were analyzed using descriptive and comparative statistics (chi-square, Mann-Whitney U and Wilcoxon signed ranks tests) with p = 0.01 considered statistically significant. RESULTS: One to 2 weeks after LVAD implantation, patients were quite satisfied with their lives, experienced moderately low amounts of stress, coped well, and perceived themselves as having good health and QOL, low symptom distress, and moderately low functional disability. Patients reported significantly better QOL, more satisfaction with health and functioning, and were significantly less distressed by symptoms from immediately pre-operatively to post-operatively. However, patients reported significantly more self-care disability and more dissatisfaction with socioeconomic areas of life from before to immediately after surgery. Psychological distress was low and did not change with time. CONCLUSION: Given that QOL improved from before to after LVAD implantation, our findings provide a springboard for investigation of the impact of LVADs on long-term QOL outcomes.

Bridge to transplant with the HeartMate device.

The incidence and prevalence of chronic heart failure continues to increase, with an estimated 400,000 new cases per year in the United States. Cardiac transplantation is an effective therapy but is severely limited to approximately 2300 patients per year due to the donor shortage. With ever increasing waiting times, a significant number of patients become severely debilitated or expire prior to transplantation. A mechanical circulatory support device was first used as a "bridge to transplantation" in 1969. Since then, mechanical devices have increased tremendously in reliability and efficaciousness. The HeartMate left ventricular assist device (LVAD) has been utilized extensively in a bridge to transplant application with excellent results. Patients refractory to aggressive medical management can be sustained reliably until transplantation. In addition, bridging allows for the correction of physiologic and metabolic dearrangements often seen in these severely ill patients prior to transplantation. Nutritional, economic, and quality-of-life issues also favor earlier LVAD placement in refractory patients. This reportsummarizes the overall bridging experience with the HeartMate LVAD and focuses on our experience with this device at Rush-Presbyterian-St. Luke's Medical Center.

Left ventricular assist device implantation: short and long-term surgical complications.

Long-term implanted left ventricular assist devices (LVADs) have significantly improved the care of patients awaiting heart transplantation and will provide an alternative therapy to select patients with heart failure. However, although the technology and clinical results continue to improve, LVAD implantation is still associated with a significant level of complications. Left ventricular assist device-associated complications can be broadly divided by their temporal occurrence. Early complications include perioperative hemorrhage, air embolism, and right ventricular failure. Beyond the perioperative period, late complications consist primarily of infection, thromboembolism, and primary device failure. An improved understanding of the mechanisms involved should aid the clinician in further reducing the incidence of these occurrences.

The use of APACHE II scores to select candidates for left ventricular assist device placement. Acute Physiology and Chronic Health Evaluation.

BACKGROUND: The growth in left ventricular assist device (LVAD) use has been hampered by high morbidity and mortality rates and cost. The purpose of this study was to help improve patient selection for LVAD placement by determining whether the Acute Physiology and Chronic Health Evaluation II (APACHE II) scoring system, a multiparameter, physiology-based predictor of outcome, could be used to predict outcome after LVAD placement and thus help determine optimum timing of LVAD placement. METHODS: This was a retrospective analysis of a prospective cohort observational study consisting of 2 groups: (1) 50 patients with severe heart failure who did not receive LVAD placement after initial evaluation and (2) 31 patients who did receive LVAD placement. Patients included in the study were in severe heart failure on the basis of 3 of the following: lung crackles, S3, peripheral edema, ejection fraction < 0.30, systolic blood pressure < 80 mm Hg, progressive prerenal azotemia, altered level of consciousness, gastrointestinal ischemia or congestion, or persistent although reversible pulmonary hypertension in spite of maximal medical therapy, including intravenous inotropes. The decision for LVAD placement was at the discretion of the attending physician. RESULTS: Both LVAD- and non-LVAD-treated patients were similar in cause of heart failure, APACHE II scores, and other baseline laboratory parameters. Survival time with a log-logistic model was better for LVAD-treated patients, p=.0266. Although Kaplan Meier analysis showed a trend toward better survival rates in the LVAD-treated patient, the Cox proportional hazards revealed that LVAD-treated patients had better survival (relative risk ratio, 95% confidence interval=0.305, 0.110 to 0.892; p=.0219) after adjustment for APACHE II score. Each unit increase in APACHE II independently predicted death (relative risk ratios, 95% confidence interval=1.139, 1.055 to 1.231; p=.0009). Patients with medium APACHE II (11 to 20) scores in particular benefitted from LVAD treatment. CONCLUSION: LVAD placement for severe heart failure (not restricted to cardiogenic shock) improves survival. APACHE II can aid in deciding the timing of LVAD placement in patients with heart failure who may not have attained conventional hemodynamic criteria for LVAD placement. Patients who had APACHE II scores between 11 and 20 derived the greatest benefit from LVAD placement.

Assessment of small-diameter aortic mechanical prostheses: physiological relevance of the Doppler gradient, utility of flow augmentation, and limitations of orifice area estimation.

BACKGROUND: Noninvasive assessment of functionally stenotic small-diameter aortic mechanical prostheses is complicated by theoretical constraints relating to the hemodynamic relevance of Doppler-derived transprosthetic gradients. To establish the utility of Doppler echocardiography for evaluation of these valves, 20-mm Medtronic Hall and 19-mm St Jude prostheses were studied in vitro and in vivo. METHODS AND RESULTS: Relations between the orifice transprosthetic gradient (equivalent to Doppler), the downstream gradient in the zone of recovered pressure (equivalent to catheter), and fluid mechanical energy losses were examined in vitro. Pressure-flow relations across the 2 prostheses were evaluated by Doppler echocardiography in vivo. For both types of prosthesis in vitro, the orifice was higher than the downstream gradient (P<0.001), and fluid mechanical energy losses were as strongly correlated with orifice as with downstream pressure gradients (r2=0.99 for both). Orifice and downstream gradients were higher and fluid mechanical energy losses were larger for the St Jude than the Medtronic Hall valve (all P<0.001). Whereas estimated effective orifice areas for the 2 valves in vivo were not significantly different, model-independent dynamic analysis of pressure-flow relations revealed higher gradients for the St Jude than the Medtronic Hall valve at a given flow rate (P<0.05). CONCLUSIONS: Even in the presence of significant pressure recovery, the Doppler-derived gradient across small-diameter aortic mechanical prostheses does have hemodynamic relevance insofar as it reflects myocardial energy expenditure. Small differences in function between stenotic aortic mechanical prostheses, undetectable by conventional orifice area estimations, can be identified by dynamic Doppler echocardiographic analysis of pressure-flow relations.

Plasma vitamins E and C concentrations of adult patients during cardiopulmonary bypass.

OBJECTIVE: This study was designed with two aims: 1) to determine if the coronary artery bypass graft (CABG) procedure alters plasma vitamin E and C concentrations of adult patients through repeated determinations of vitamin levels at time points before, during and following CABG, and 2) to assess whether plasma vitamin E concentrations reflect myocardial tissue content. METHODS: A consecutive sample of 38 patients undergoing CABG surgery at a Midwest tertiary care hospital was enrolled. Patients receiving blood transfusions before or during surgery were excluded. RESULTS: Plasma vitamin E/total lipid ratios rose with reperfusion, remained elevated immediately following bypass, and fell to preoperative concentrations by 24 hours. Plasma vitamin E/total cholesterol levels varied little throughout this time course. Both plasma uric acid and ascorbate concentrations (corrected for hemodilution) also rose by the preischemic interval, and remained elevated until a return to preoperative levels by 24 hours. Corrected malondialdehyde (MDA) concentrations rose by pre-ischemia but returned more quickly to preoperative levels. Atrial appendage tissue vitamin E concentrations bore a significant relationship to those of plasma prior to surgery (r=+0.49, p=0.004). Reported supplement use, plasma concentrations and body mass index contributed to the variability in atrial tissue concentrations of vitamin E. CONCLUSIONS: In short, when not confounded by transfusions or hemodilution, several peripheral indices of antioxidants increase with the reperfusion segment of CABG procedure and return to baseline levels within 24 hours of surgery. Parallel changes in MDA were observed. The observed changes are consistent with the hypothesis that oxidative stress accompanies the ischemia-reperfusion components of the CABG procedure.

Mechanical circulatory assistance: changing indications and options.

The previously high rates of morbidity and mortality associated with implantation of LVADs for long-term support have continued to decline through design improvements, better patient selection criteria, and greater clinical experience. Patients which chronic heart failure awaiting transplantation should be considered for LVAD placement early in their clinical course, before irreversible end-organ dysfunction occurs. Both the Novacor and the vented electric HeartMate LVADs are currently being evaluated under "discharge to home" protocols for patients awaiting heart transplantation; the results will have tremendous economic and quality-of-life implications. Currently available devices have achieved a level of reliability that will allow for protocols involving device implantation as an alternative to transplantation in the near future. Physicians will then have an effective therapy available for the increasing number of heart failure patients awaiting a limited number of donor hearts, as well as for those patients not considered to be candidates for transplantation by traditional criteria.

Role of maximal oxygen consumption in establishment of heart transplant candidacy for heart failure patients with intermediate exercise tolerance.

Maximal exercise oxygen consumption (VO2max) was measured in patients with chronic congestive heart failure undergoing evaluation for heart transplantation. Although VO2max correlated with survival for the group as a whole, it did not demonstrate survival discrimination for patients in the intermediate range (VO2max = 12 to 17 ml/kg/min) and should therefore not be used as a benchmark test for determination of appropriateness for cardiac transplantation in this group of patients.

Infectious complications in left ventricular assist device recipients.

The left ventricular assist device (LVAD) has revolutionized the care of patients with heart failure who are awaiting transplantation. Despite reports of significant infection rates associated with LVAD implantation, few data are available concerning the management of LVAD-related infections and their impact on transplantation. Eight (40%) of our first 20 LVAD recipients developed infections. LVAD-related bloodstream infection occurred in three (15%) patients; infection was due to Staphylococcus aureus in one case, coagulase-negative staphylococci in the second case, and S. aureus and Candida tropicalis in the third case. All three patients were treated with courses of antibiotics that were appropriate for prosthetic valve endocarditis and received antibiotics for at least 6 weeks. All infected patients underwent successful transplantation and had no evidence of recurrence of infection up to 16 months postoperatively. Our experience suggests that LVAD infections can be successfully treated without device removal and that cardiac transplantation can be performed in individuals with LVAD-related bloodstream infection.

Extended aortic valvuloplasty for recurrent valvular stenosis and regurgitation in children.

Recurrent significant aortic valvular stenosis or regurgitation, or both, after balloon or open valvotomy in pediatric patients often necessitates aortic valve replacement. In an attempt to preserve the aortic valve, we performed extended aortic valvuloplasty in 21 children with recurrent aortic valve stenosis or regurgitation from January 1989 to March 1993. Previous related procedures were one open aortic valvotomy or more (n = 15), balloon valvotomy (n = 4), balloon valvotomy after surgical valvotomy (n = 1), and repair of iatrogenic valve tear (n = 1). Mean age at the time of the extended aortic valvuloplasty was 6 +/- 3.4 years. Mean pressure gradient across the aortic valve was 56 +/- 12 torr. Regurgitation was moderate (grade 2 to 3) in nine and severe (grade 4) in 12 patients. Extended aortic valvuloplasty techniques consisted of thinning of valve leaflets (n = 15), augmentation of scarred and retracted leaflets with autologous pericardium (n = 11), resuspension of the augmented leaflet (n = 14), release of the rudimentary commissure from the aortic wall (n = 5), extension of the valvotomy incision into the aortic wall on both sides of the commissure (n = 20), patch repair of the sinus of Valsalva perforation (n = 1), reapproximation of tears (n = 5), and narrowing of the ventriculoaortic junction (n = 2). No operative deaths occurred. The postoperative mean pressure gradient, assessed by most recent Doppler echocardiography or cardiac catheterization at a follow-up of 18 +/- 6 months, was 19 +/- 6 torr (p < 0.01 versus the preoperative gradient). Aortic regurgitation was absent in 13, mild in 6, and moderate-to-severe, necessitating subsequent aortic valve replacement, in 2. This short-term experience indicates that extended aortic valvuloplasty is a safe and effective surgical approach that minimizes the need for aortic valve replacement in children with significant recurrent aortic valve stenosis or regurgitation.

Partial median sternotomy for repair of heart defects: a cosmetic approach.

A modified median sternotomy incision that results in a cosmetically appealing scar is described. It includes the use of a low-lying short skin incision and partial transection of the sternum. The outcome in 182 infants and children indicates that this approach is safe, provides adequate exposure, and has excellent cosmetic results.

Perioperative arterial monitoring in patients with severe occlusive disease.

Special problems exist in the study and intraoperative monitoring of patients with severe occlusive vascular disease involving all extremities and with symptomatic brachiocephalic or coronary artery disease. We report 3 such patients who underwent arteriography via a percutaneous translumbar aortic catheter. All patients then underwent successful arterial reconstructive procedures utilizing the same translumbar catheter for arterial pressure monitoring and blood gas analysis. Percutaneous translumbar aortic catheters provide both a safe method for studying patients with four extremity occlusive vascular disease and reliable arterial access to monitor these patients intraoperatively.