Prevalence, Pathophysiology, and Clinical Significance of Post-heart Transplant Atrial Fibrillation and Atrial Flutter

BACKGROUND

Atrial rhythm disturbances, in particular atrial fibrillation (AF) and flutter (AFL), are common in the denervated transplanted heart. However, there is a relative paucity of data in the prevalence, mechanism of arrhythmia, and long-term significance.

OBJECTIVES

(1) Determine the prevalence of AF and AFL in heart transplant patients, (2) define the echo/Doppler features associated with arrhythmia, and (3) evaluate the impact of arrhythmia on long-term survival.

METHODS

All patients who received an orthotopic heart transplant at the Mayo Clinic, Rochester, Minnesota, between 1988 and 2000 were included. Analysis of serial electrocardiograms and Holter monitor records provided evidence of AF or AFL development. Variables including general patient demographics, histology-proven rejection numbers and grades, results of serial coronary angiography, endomyocardial biopsy specimens, and echocardiographic studies performed at 6 weeks and 3 years after transplant were obtained to determine variables predictive of arrhythmia development.

RESULTS

There were 167 heart transplant recipients, of which 16 (9.5%) developed AF and another 25 (15.0%) developed AFL over 6.5 +/- 3.4 years. Patients who developed AF or AFL had lower left ventricular (LV) ejection fractions (56.6% +/- 1.6% vs 62.5% +/- 1.5%, p < 0.05), higher LV end-systolic dimensions (LVESD) (33.6 +/- 1.12 mm vs 29.7 +/- 0.97 mm, p < 0.01), higher right atrial volume indexes (43.2 +/- 12.3 ml vs 35 +/- 5.3 ml, p < 0.03), lower mitral deceleration time (145 +/- 8 msec vs 160 +/- 12 msec, p < 0.05), and lower late mitral annulus tissue a' velocities (0.06 +/- 0.005 cm/sec vs 0.08 +/- 0.01 cm/sec, p < 0.02) compared with an age- and gender-matched Sinus Rhythm Group. Grade 3 rejection was a time-dependent covariate predictor of AFL risk (hazard ratio [HR], 2.95; 95% confidence interval [CI], 1.3-6.6, p < 0.008) but not AF (HR, 2.264; 95% CI, 0.72-7.1; p = 0.10). Thirty-nine of 167 patients died: 13 in the arrhythmia group and 26 in the normal sinus rhythm group. Development of atrial dysrhythmia adversely affected the outcome in the first 5 years (p < 0.001) compared with normal sinus rhythm. Predictors of long-term mortality included AF/AFL (HR, 2.88; 95% CI, 1.38-5.96; p < 0.004), age at transplant (HR, 1.04; 95% CI, 1.00-1.07, p < 0.03), coronary artery disease (HR, 2.655; 95% CI, 1.25-5.64; p = 0.01), pre-transplant cardiac amyloidosis (HR, 5.02; 95% CI 2.37-10.62; p < 0.001), right atrial volume index (HR, 1.03; 95% CI, 1.00-10.7; p = 0.03), mitral deceleration time <160 msec (p < 0.01), and LVESD >30 mm (p < 0.04).

CONCLUSION

Development of AF/AFL post-heart transplantation is not uncommon and is associated with decreased long-term survival. Cumulative effects of repeated moderate-to-severe (grade 3 or more) rejections that result in increased cardiac fibrosis are associated with the development of AFL, but not AF. Similarly advanced restrictive diastolic dysfunction caused by fibrosis from repeated moderate-to-severe (grade 3 or more) rejections was predominant in the patients with arrhythmia and was a marker of poor long-term outcome.

Elevated Donor Troponin Levels Are Associated with a Lower Frequency of Allograft Vasculopathy

BACKGROUND

Cardiac allograft vasculopathy (CAV) is considered a major cause of morbidity and mortality in transplant recipients and may reflect immune-mediated endothelial injury in response to the donor heart. Elevated troponin levels in the donor serum might provide a marker for this phenomenon; therefore, we evaluated the relationship of donor troponin levels to the development of CAV.

METHODS

A retrospective analysis of troponin levels was undertaken from cardiac donor patients, and transplant recipients were monitored for the development of vasculopathy by angiography (N = 171).

RESULTS

Angiographically significant CAV developed in 6% of transplantation patients and troponin levels were inversely related to the severity of CAV.

CONCLUSIONS

Elevated donor troponin levels are not associated with the development of CAV but rather with a significantly reduced long-term risk of developing CAV, suggesting a possible protective effect of donor released protein.

Successful Use of Thoratec Biventricular Support in a Small Child Awaiting Cardiac Transplantation

The use of paracorporeal mechanical biventricular support devices either as a bridge to transplantation or while awaiting recovery of the failing heart has been well described in the literature. The majority of these reports detail conditions specific to the adult population. We describe use of the Thoratec ventricular assist device (Thoratec Corp, Pleasanton, CA) in the smallest known cardiomyopathy patient to date to be successfully supported with an emergent biventricular device before subsequent cardiac transplantation. The operative technique, pump settings, and modifications utilized to optimize peripheral perfusion are detailed.

Mitral regurgitation in patients with advanced systolic heart failure

BACKGROUND

Mitral regurgitation (MR) may develop in patients with advanced systolic congestive heart failure (CHF) without organic mitral valve disease and contribute to worsening symptoms and survival. Surgical mitral annuloplasty improves symptoms in patients with advanced CHF, and percutaneous approaches to mitral annuloplasty are being developed. Our objective was to define the prevalence, clinical correlates, and prognostic implications of functional MR and the use of mitral annuloplasty in patients with advanced systolic CHF evaluated in a heart failure clinic.

METHODS AND RESULTS

We reviewed clinical, echocardiographic, and survival data from all patients with advanced systolic CHF (New York Heart Association class III or IV; ejection fraction </=35%) resulting from ischemic or idiopathic cardiomyopathy who were evaluated at our heart failure clinic between January 1996 and September 2001. Of 716 patients with advanced CHF, 558 had satisfactory baseline echocardiograms performed at our institution. Among these patients, MR was severe in 24 (4.3%), moderate-severe in 70 (12.5%), moderate in 122 (21.9%), mild-moderate in 66 (11.8%), mild in 218 (39.1%), and absent or present as only a trace in 58 (10.4%). The severity of MR was confirmed by quantitative analysis in 72% of patients with hemodynamically significant MR (more than moderate). The severity of MR correlated with the severity of systolic dysfunction (P <.001), ventricular dilatation (P <.03), atrial dilatation (P <.001), diastolic dysfunction (P <.001), and pulmonary hypertension (P <.001). Coexistent severe or moderate-severe tricuspid regurgitation was present in 25% of patients with hemodynamically significant MR. Patients with hemodynamically significant MR had higher mortality (P=.03) but not when controlling for age, sex, cause, New York Heart Association class, and ejection fraction (P=.95). Only 3 patients subsequently underwent mitral valve repair.

CONCLUSION

Among patients with advanced CHF, hemodynamically significant MR is common. The severity of MR did not provide independent prognostic information in this group recognized to have uniformly high mortality.

Mitral and tricuspid valve repair in patients with previous mediastinal radiation therapy

BACKGROUND

The purpose of this study was to evaluate outcomes of mitral and tricuspid valve repair after mediastinal radiation therapy.

METHODS

From 1976 to 2001, 22 patients (mean age 61 +/- 14 years) underwent mitral (n = 14), tricuspid (n = 6), or both (n = 2) valve repairs 15 +/- 9 years after mediastinal radiation therapy. Concomitant procedures included coronary artery bypass graft, 11 patients; valve replacement, 6 patients (4 aortic, 3 mitral, 1 tricuspid, and 1 pulmonary); and pericardiectomy, 4 patients.

RESULTS

Total follow-up was 82.5 patient-years (mean 3.7 +/- 3.3 years). Early mortality was 3 patients. There were 7 late deaths, 4 of which were of cardiovascular origin. Of the 19 early survivors, 2 required subsequent valve replacements, and 1 required cardiac transplantation 3.4 +/- 2.8 years after valve repair. One patient died after reoperation. In 4 patients who did not undergo reoperation, echocardiographic examinations showed progressive deterioration of their repaired valve function. Overall survival, freedom from cardiac death, and freedom from valve reoperation or cardiac transplantation at 5 years for early survivors was 66%, 85%, and 88%, respectively. New York Heart Association functional class at follow-up was I or II in 8 of the 12 late survivors.

CONCLUSIONS

Functional status was good in two-thirds of late survivors. However, severe dysfunction of the repaired valve developed in 32% of early survivors and 16% required further surgery. Valve repair is technically feasible in selected patients after mediastinal radiation therapy; however, the limited durability of repairs after mediastinal radiation in this series suggests that valve replacement might be preferable.

Is early anticoagulation with warfarin necessary after bioprosthetic aortic valve replacement?

OBJECTIVES

Freedom from anticoagulation is the principal advantage of bioprosthesis; however, the American Heart Association/American College of Cardiology and the American College of Chest Physicians guidelines recommend early anticoagulation with heparin, followed by warfarin for 3 months after bioprosthetic aortic valve replacement. We examined neurologic events within 90 days of bioprosthetic aortic valve replacement at our institution.

METHODS

Between 1993 and 2000, 1151 patients underwent bioprosthetic aortic valve replacement with (641) or without (510) associated coronary artery bypass. By surgeon preference, 624 had early postoperative anticoagulation (AC+) and 527 did not (AC-). In the AC- group, 410 patients (78%) received antiplatelet therapy. Groups were similar with respect to gender (female, 36% AC+ vs 40% AC-, P = .21), hypertension (64% AC+ vs 61%, P = .27), and prior stroke (7.6% AC+ vs 8.5% AC-, P = .54). The AC+ group was slightly younger than the AC- group (median, 76 years vs 78 years, P = .006).

RESULTS

Operative mortality was 4.1% with 43 (3.7%) cerebrovascular events within 90 days. Excluding 18 deficits apparent upon emergence from anesthesia, we found that postoperative cerebrovascular accident occurred in 2.4% of AC+ and 1.9% AC- patients. By multivariable analysis, the only predictor of operative mortality was hypertension ( P < .0001). Postoperative cerebrovascular accident was unrelated to warfarin use ( P = .32). The incidence of mediastinal bleeding requiring reexploration was similar (5.0% vs 7.4%), as were other bleeding complications in the first 90 days (1.1% vs 0.8%). No variables were predictive of bleeding by multivariate analysis.

CONCLUSIONS

Although these data do not address the role of antiplatelet agents, early anticoagulation with warfarin after bioprosthetic aortic valve replacement did not appear to protect against neurologic events.

Operative risk of reoperative aortic valve replacement

OBJECTIVE

The contemporary risk of reoperative aortic valve replacement is ill-defined. We therefore compared the recent early results of reoperative and primary aortic valve replacement in our institution.

METHODS

Between January 1993 and January 2001, a total of 162 patients underwent reoperative aortic valve replacement with or without coronary artery bypass grafting, and 2290 underwent primary aortic valve replacement with or without coronary artery bypass grafting. The reoperative and primary groups were similar with regard to gender (37% female in both), preoperative New York Heart Association functional class (2.8 +/- 1 vs 2.8 +/- 1), and ejection fraction (58% +/- 15% vs 57% +/- 15%). Patients undergoing reoperative aortic valve replacement were younger than those undergoing primary aortic valve replacement (64 +/- 15 years vs 70 +/- 13 years, P < .001). Previous prostheses were xenografts in 77 patients (48%), homografts and autografts in 25 (15%), and mechanical prostheses in 60 (37%). Mean time to reoperation was 9.7 +/- 6.8 years.

RESULTS

Early mortality for reoperative aortic valve replacement (8/162, 5%) was not statistically different from that for primary aortic valve replacement (71/2290, 3%, P = .20). Endocarditis was more common in the reoperative group (22% vs 3%, P < .001); when endocarditis was excluded from the analysis, early mortality was 3% in both groups. Multivariate predictors for early mortality were prosthetic valve endocarditis ( P < .001, odds ratio 9.8), advanced preoperative functional class ( P < .001, odds ratio 2.0), peripheral vascular disease ( P = .008, odds ratio 2.0), preserved left ventricular ejection fraction ( P = .004, odds ratio 0.98), and male gender ( P = .009, odds ratio 0.49). After adjustment for these factors, there was no difference in early mortality between the groups ( P = .095).

CONCLUSION

The risk of reoperative aortic valve replacement is similar to that for primary aortic valve replacement. These data support the expanded use of bioprosthetic valves in younger patients.

Surgery for Aneurysms of the Aortic Root

BACKGROUND

This study evaluated long-term results of aortic root replacement and valve-preserving aortic root reconstruction for patients with aneurysms involving the aortic root.

METHODS AND RESULTS

Two-hundred three patients aged 53+/-16 years (mean+/-SD; 153 male, 50 female) underwent elective or urgent aortic root surgery from 1971 to 2000 for an aortic root aneurysm: 149 patients underwent a composite valve conduit reconstruction, and 54 patients underwent valve-preserving aortic root reconstruction. Fifty patients had Marfan syndrome. In-hospital and 30-day mortality was 4.0% (8/203) overall: for a composite valve conduit procedure, the corresponding value was 4.0% (6/149) and for valve-preserving procedure, 3.7% (2/54) (P=NS). Morbidity included 3 strokes (1%), 10 perioperative myocardial infarctions (5%), and 8 reoperations for bleeding (4%). Actuarial survival at 5, 10, 15, and 20 years was 93% (95% confidence interval [CI] = 88% to 97%), 79% (95% CI = 71% to 87%), 67% (95% CI = 57% to 79%), and 52% (95% CI = 36% to 69%), respectively. Freedom from reoperation was 72% (95% CI = 54% to 86%) at 20 years. Complications with anticoagulation occurred in 29 patients; with valve thrombosis, in 2; and with hemorrhage, in 27 (4 life threatening and 23 minor). Freedom from thromboembolism was 91% (95% CI = 77% to 98%) at 20 years. Freedom from endocarditis was 99% (95% CI = 92% to 100%) at 20 years. Multivariate analysis revealed preoperative mitral valve regurgitation (+3 to 4) and older age to be significant predictors of late death (P< or =0.005), and Marfan syndrome, initial valve-preserving aortic root reconstruction, and need for a concomitant procedure at initial operation to be significant predictors of the need for reoperation (P< or =0.01).

CONCLUSIONS

Aortic root replacement for aortic root aneurysms can be done with low morbidity and mortality. Composite valve conduit reconstruction resulted in a durable result. There were few serious complications related to the need for long-term anticoagulation or a prosthetic valve. Reoperation was most commonly required because of failure of the aortic valve when a valve-preserving aortic root reconstruction was performed or for other cardiac or aortic disease elsewhere.

Results of mitral surgery in octogenarians with isolated nonrheumatic mitral regurgitation

BACKGROUND

Increasing numbers of elderly patients are now referred for mitral valve operations. It has been unclear whether the results offset the risk of intervention in this patient population.

METHODS

We obtained clinical follow-up through May 2002 of 59 patients 80 years or older who underwent first-time isolated mitral valve repair (46 patients) or replacement (13 patients) for nonischemic, nonrheumatic mitral regurgitation from January 1990 to June 2000. The mean duration of follow-up was 68 +/- 33 months. Observed survival was compared with the expected survival of persons of the same age and gender in the general population.

RESULTS

Preoperatively 79% of patients were in New York Heart Association (NYHA) class III-IV. Operative mortality was 1.7%. Overall 1- and 5-year survival was 89% and 61%. One- and 5-year freedom from thromboembolic complications in hospital survivors was 97% and 84%. One- and 5-year freedom from heart-related hospitalization in hospital survivors was 89% and 78%. There were no reoperations. Twenty-nine patients underwent an echocardiographic follow-up; 31% of them exhibited moderate or more regurgitation. Of 37 surviving patients at follow-up, 78% were in NYHA functional class I-II. No statistically significant difference was noted between the observed survival postoperatively and the expected survival of persons of the same age and gender in the general population. In a univariate analysis, only preoperative left ventricular ejection fraction greater than 40% was significantly associated with freedom from late heart-related mortality (95% confidence interval 62%-92%, p = 0.01) and with freedom from heart-related hospitalization (95% CI 68%-95%, p < 0.01).

CONCLUSIONS

Native mitral valve surgery for isolated nonischemic, nonrheumatic disease in octogenarians resulted in a survival rate comparable with that of the general population. It also exhibited substantial improvement regarding the functional status of the patient. Reparative techniques did not result in a survival advantage compared with replacement but did prove to be a reliable approach. Surgery performed in an early stage, preceding the development of left ventricular dysfunction, was associated with an improved freedom from late cardiac complications.

Risk of repeat mitral valve replacement for failed mitral valve prostheses

BACKGROUND

Advances in tissue prosthetic valve design and manufacturing have stimulated renewed interest in the use of biological valves in younger patients. This approach, however, risks reoperation. We therefore reviewed our recent experience with repeat mitral valve replacement to better define its contemporary risks.

METHODS

Using a computerized database, we identified and compared 106 patients undergoing repeat mitral valve replacement with 562 control patients undergoing primary mitral valve replacement between January 1993 and December 2000 at our institution.

RESULTS

There were no significant differences between repeat and primary surgery groups with respect to age (mean 66 +/- 12 vs 64 +/- 13 years), gender distribution (women 65% vs 64%), preoperative functional class, ejection fraction, or active endocarditis (6.6% vs 3.4%). The indication for reoperation in the repeat group was structural dysfunction in 49 patients (46%), paravalvular leak in 21 patients (20%), nonstructural dysfunction in 11 patients (10%), and progression of other native valve disease in 8 patients (8%). Prior prostheses were mechanical in 46 patients (43%). Mean time to reoperation was 11.5 +/- 7.1 years. There were 5 deaths out of 106 patients in the repeat group (4.7%) and there were 23 deaths out of 562 patients in the control group (4.1%) (p = NS). Multivariate analysis identified prior myocardial infarction (p = 0.014, odds ratio 2.9) and nonelective surgical status (p = 0.004, odds ratio 2.3) as significant predictors of operative mortality.

CONCLUSIONS

The risk of repeat mitral valve replacement was low suggesting that there should be less reluctance to recommend patients choose a bioprosthesis over a mechanical prosthesis. Given the expected durability of current designs, bioprosthetic use may be explored in younger patients without subjecting those individuals to excessive risk.

Is repair of aortic valve regurgitation a safe alternative to valve replacement?

OBJECTIVE

To assess outcome of valve repair in patients with aortic valve regurgitation with emphasis on incidence and risk of reoperation.

METHODS

We retrospectively reviewed 160 consecutive patients (127 men) who underwent aortic valve repair between 1986 and 2001. Ages ranged from 14 to 84 years (mean 55 +/- 17 years). Patients were categorized according to the main etiology of valve disease; 63 patients (39%) had annular dilation leading to central leakage, 54 (34%) had bicuspid valve, 34 (21%) with tricuspid valve had cusp prolapse, and 9 (6%) had cusp perforation. Repair methods included commissural plication (n = 154, 96%), partial cusp resection with plication (n = 47, 29%), resuspension or cusp shortening (n = 44, 28%), and closure of cusp perforation (n = 10, 6%).

RESULTS

There was 1 early death (0.6%). Two patients required re-repair of the aortic valve during initial hospitalization. During a mean follow-up of 4.2 years, there were 16 late deaths. Overall, 16 of 159 hospital survivors had late reoperation on the aortic valve (mean interval 2.8 years) without early mortality. Risks of reoperation on the aortic valve were 9%, 11%, and 15% at 3, 5, and 7 years, respectively.

CONCLUSIONS

Aortic valve repair can be performed with low risk and excellent freedom from valve-related morbidity and mortality. Late recurrence of aortic valve regurgitation led to reoperation in 8.8% of patients, but mortality associated with subsequent procedures is low. Aortic valve repair appears to be a good option for selected patients, particularly young patients who wish to avoid chronic anticoagulation with warfarin.

Is there a role for the left ventricle apical-aortic conduit for acquired aortic stenosis?

BACKGROUND AND AIM OF THE STUDY

Aortic valve replacement (AVR) in patients with a heavily calcified ascending aorta and aortic root, or with conditions that preclude a median sternotomy, poses a formidable challenge. A left ventricle apical-aortic conduit (AAC) is an alternative in these situations. Herein, the authors' experience with AAC in adult patients with acquired aortic stenosis is reported.

METHODS

Between 1995 and 2003, 13 patients (mean age 71 years) underwent AAC for severe symptomatic aortic stenosis (mean valve area 0.65 +/- 0.02 cm2). Indications for AAC were heavily calcified ascending aorta and aortic root (n = 5), patent retrosternal mammary grafts (n = 4), calcified ascending aorta and aortic root plus patent retrosternal mammary graft (n = 1), retrosternal colonic interposition (n = 1) and multiple previous sternotomies (n = 2). Seven patients had previous coronary artery bypass grafting (CABG). The mean preoperative left ventricular ejection fraction was 50 +/- 4%.

RESULTS

AAC were performed under cardiopulmonary bypass through a left thoracotomy (n = 10), median sternotomy (n = 2) or bilateral thoracotomy (n = 1). Hearts were kept beating (n = 5) or fibrillated (n = 7). Circulatory arrest was used in one patient. Composite Dacron conduits with biological (n = 6), mechanical (n = 4) or homograft (n = 2) valves were used. Distal anastomoses were performed in the descending thoracic aorta (n = 12) or in the left iliac artery (n = 1). Two patients underwent simultaneous CABG. Three patients died in-hospital from ventricular failure (n = 1), intravascular thrombosis (n = 1) and multi-organ failure (n = 1). The mean hospital stay was 26 days. Complications included respiratory failure requiring tracheostomy (n = 2), stroke (n = 1) and re-exploration for bleeding (n = 2). At a mean follow up of 2.1 years, there have been four late deaths; causes of death were congestive heart failure (n = 2), ischemic cardiomyopathy (n = 1) and cancer (n = 1).

CONCLUSION

AAC provides an acceptable alternative to AVR in selected patients who are at exceedingly high risk for the standard procedure.

Late outcome of mitral valve surgery for patients with coronary artery disease

BACKGROUND

We plan to determine whether the cause of mitral valve regurgitation, ischemic or degenerative, affects survival after combined mitral valve repair or replacement and coronary artery bypass grafting (CABG) surgery and to assess the influence of residual mitral regurgitation on late outcome.

METHODS

A retrospective study was made of 302 patients having mitral valve repair or replacement and CABG from January 1987 through December 1996. Risk factors for death, for development of New York Heart Association class III or IV congestive heart failure (CHF), and recurrent mitral valve regurgitation were identified by proportional hazards analysis.

RESULTS

The cause of mitral regurgitation was ischemic in 137 patients (45%) and degenerative in 165 patients (55%). Valve replacement was performed in 51 patients (17%) and valve repair in 251 patients (83%). Median follow-up was 64 months. Ten-year actuarial survival rates were 33% (95% confidence interval: 22% to 47%) in the ischemic group and 52% (95% confidence interval: 42% to 64%) in the degenerative group. Univariate predictors of death, were entered into a multivariate model. Older age, ejection fraction of 35% or less, three-vessel coronary artery disease, replacement of the mitral valve, and residual mitral regurgitation at dismissal were independent risk factors for death. The cause of mitral valve regurgitation (ischemic or degenerative) was not an independent predictor of long-term survival, class III or IV CHF, or recurrent regurgitation.

CONCLUSIONS

Survival after mitral valve surgery and CABG is determined by the extent of coronary disease and ventricular dysfunction and by the success of the valve procedure; etiology of mitral valve regurgitation has relatively little impact on late outcome.

Neuroendocrine and behavioral effects of high-dose anabolic steroid administration in male normal volunteers

OBJECTIVE

Despite widespread abuse of anabolic-androgenic steroids (AAS), the endocrine effects of supraphysiologic doses of these compounds remain unclear. We administered the AAS methyltestosterone (MT) to 20 normal volunteers in an in-patient setting, examined its effects on levels of pituitary-gonadal, -thyroid, and -adrenal hormones, and examined potential relationships between endocrine changes and MT-induced psychological symptoms.

METHOD

Subjects received MT (three days of 40 mg/day, then three days of 240 mg/day) or placebo in a fixed sequence with neither subjects nor raters aware of order. Samples were obtained at the ends of the baseline, high-dose MT and withdrawal phases. Potential relationships between hormonal changes and visual analog scale measured mood changes were examined.

RESULTS

Significant decreases in plasma levels of gonadotropins, gonadal steroids, sex hormone binding globulin, free T3 and T4, and thyroid binding globulin (Bonferroni t, p<0.01 for each) were seen during high-dose MT; free thyroxine and TSH increased during high-dose MT, with TSH increases reaching significance during withdrawal. No significant changes in pituitary-adrenal hormones were observed. Changes in free thyroxine significantly correlated with changes in aggressiveness (anger, violent feelings, irritability) (r=0.5,p=0.02) and changes in total testosterone correlated significantly with changes in cognitive cluster symptoms (forgetfulness, distractibility) (r=0.52,p=0.02). Hormonal changes did not correlate with plasma MT levels.

CONCLUSIONS

Acute high-dose MT administration acutely suppresses the reproductive axis and significantly impacts thyroid axis balance without a consistent effect on pituitary-adrenal hormones. Mood and behavioral effects observed during AAS use may in part reflect secondary hormonal changes.

Mycotic aneurysm of the left ventricle: echocardiographic diagnosis

We report an unusual case of myocardial mycotic aneurysm of the left ventricle resulting from a healed myocardial abscess caused by an aortic regurgitant jet lesion. The diagnosis was made during intraoperative transesophageal echocardiography and confirmed by surgical inspection. The echocardiographic features are described.

Valve-preserving aortic root reconstruction: a comparison of techniques

BACKGROUND AND AIM OF THE STUDY

Controversy exists with regard to the indications and technique for valve-preserving aortic root reconstruction. Here, the authors' clinical experience with three techniques is reported.

METHODS

Between October 1994 and October 2000, 71 patients (46 men, 25 women; median age 53 years; range: 21-81 years) underwent aortic root reconstruction with preservation of the aortic valve and replacement of ascending aorta. Factors that affected survival and need for subsequent aortic valve replacement were analyzed using univariate analysis.

RESULTS

Indications for operation were chronic aneurysm in 65 patients, acute dissection in five, and chronic aneurysm with dissection in one patient. Forty patients were asymptomatic. Presenting symptoms included shortness of breath in 16 patients, chest pain in 14 and transient ischemic attacks in one patient. Twenty patients had Marfan syndrome. The reimplantation technique was performed in 52 patients, remodeling technique in 14, and remodeling with sinus graft root replacement technique in five. Postoperative echocardiography demonstrated absent to mild aortic insufficiency in 63 patients. Operative mortality was 2.8%. Actuarial survival was 84.1% at 5 years; freedom from reoperation was 88.8% and 78.9% at one and three years, respectively. Eleven patients (21.2%) repaired by the implantation technique required aortic valve replacement secondary to aortic valve insufficiency. By univariate analysis, the necessity of aortic cusp repair (p = 0.0009), aortic annulus size >25 mm (p = 0.04), and male gender (p = 0.04) were predictors for subsequent aortic valve replacement.

CONCLUSION

Aortic valve-preserving surgery is possible with a low morbidity and mortality. The authors' experience shows a high failure rate in males with a large annulus needing aortic cusp repair and undergoing the reimplantation technique.

Clinical predictors of exercise capacity 1 year after cardiac transplantation

BACKGROUND

The exercise capacity of cardiac transplant recipients is reduced compared with normal controls. However, clinical variables predictive of post-transplant exercise capacity have not been well defined. The objective of the present study was to identify clinical features predictive of post-transplant exercise capacity.

METHODS

Ninety-five cardiac transplant recipients underwent cardiopulmonary testing at 1 year after transplant. The exercise parameters were compared with both pre-transplant values and normal subjects. The relationships between exercise parameters and clinical characteristics were analyzed.

RESULTS

Mean peak oxygen consumption (VO(2)) and exercise test duration at 1-year post-transplant improved significantly from 16.4 to 19.9 ml/kg/min and 5.5 to 7.6 minutes, respectively (p < 0.001), but were significantly lower than for normal controls (peak VO(2) 34.0 ml/kg/min; exercise duration 11.2 minutes; p < 0.001). Age- and gender-adjusted VO(2) was 54% of predicted. Pre-operative body weight correlated strongly with post-transplant weight (r = 0.80, p < 0.001). Significant recipient predictors of 1-year post-transplant peak VO(2) identified by multivariate regression analysis were age, male gender, body mass index, exercise peak heart rate and duration of post-operative intensive care. Donor variables did not contribute significantly to post-transplant peak VO(2).

CONCLUSIONS

Peak VO(2) improved after cardiac transplantation but remained significantly impaired compared with normal subjects. In estimating the impact of cardiac transplantation on exercise capacity the most important pre-transplant factors to consider are age, gender and height and weight (or, alternatively, body mass index).

Partial normalization of the heart rate response to exercise after cardiac transplantation: frequency and relationship to exercise capacity

OBJECTIVE

To determine the frequency of partial normalization of the heart rate response to graded exercise and its relationship to exercise capacity in cardiac transplant recipients.

SUBJECTS AND METHODS

The study subjects were 95 adults (77 men, 18 women) who were available to perform a cardiopulmonary exercise test 1 year after orthotopic cardiac transplantation, which occurred between June 1988 and September 1998. All subjects received standard immunosuppressant medications. At the time of the exercise tests, the mean +/- SD age of the subjects was 49+/-14 years. The mean +/- SD resting left ventricular ejection fraction was 62%+/-8%. All subjects participated in a 6- to 8-week supervised exercise program, starting no later than 1 month after surgery. Subjects were given an exercise prescription for independent exercise training after finishing the supervised program. Self-reported weekly exercise training had a median value of 90 minutes (interquartile range, 0-210 minutes). Symptom-limited graded exercise was performed on a treadmill, with breath-by-breath analysis of expired air.

RESULTS

For the entire cohort, peak exercise oxygen uptake was 19.9+/-4.8 mL x kg(-1) x min(-1) (61%+/-15% of age and sex predicted). Thirty-two subjects (34%) had a partially normalized heart rate response to graded exercise. The frequency was similar for men (25/77 [33%]) and for women (7/18 [39%]) and was independent of recipient or donor age. Peak exercise heart rate (147+/-18 vs 134+/-21 beats/min; P=.008) and heart rate reserve (46+/-15 vs 33+/-15 beats/min; P<.001) were greater for subjects with a partial normalization of heart rate response. Peak exercise oxygen uptake was similar for subjects with or without partial normalization of the heart rate response (20.9+/-5.8 vs 19.4+/-4.2 mL x kg(-1) x min(-1); P=.22). Submaximal exercise oxygen uptake during the first few minutes of exercise was also not affected by normalization of the heart rate response.

CONCLUSION

At 1 year after cardiac transplantation, approximately one third of subjects had partial normalization of the heart rate response to graded exercise. However, a higher peak exercise heart rate and a larger heart rate reserve did not result in better aerobic exercise capacity.

The advantage of repair of mitral valve in acute endocarditis

BACKGROUND AND AIM OF THE STUDY

Mitral valve repair offers a survival benefit compared with valve replacement in surgery for non-infectious mitral regurgitation. It is unclear whether repair offers an advantage for patients undergoing mitral valve surgery for active endocarditis. Morbidity and mortality (early and late) and event-free survival were compared between the repair and replacement groups.

METHODS

Between September 1986 and July 1999, 44 patients with acute native mitral valve endocarditis underwent surgery; 28 patients had valve replacement, and 16 underwent repair. Nine patients had complex repairs including replacement of a portion of the leaflet with prosthetic patch, placement of artificial chordae, resection of a portion of both leaflets, and/or reconstruction of a commissure. The remainder had simple repairs.

RESULTS

Preoperative characteristics and indications for surgery between the two groups were similar. There were six in-hospital (21%) and six late cardiac deaths (21%) in the valve replacement group, but no early deaths or late cardiac deaths in the repair group (p <0.05). Independent risk factors for early and late death were need for associated procedures (p <0.03) and mitral valve replacement (p <0.05). Additional risk factors for late death were diabetes mellitus (p = 0.005) and hemodynamic instability as an indication for surgery (p = 0.047). Five patients undergoing valve replacement required reoperation due to recurrent endocarditis, compared with none in the repair group (p = 0.065). Mean follow up was 39+/-33 months in the repair group, and 57+/-51 months in the replacement group.

CONCLUSION

Early and late mortality and event-free survival were better in patients undergoing mitral valve repair compared with replacement for acute endocarditis. Valve repair should be carried out whenever possible in this patient group.

Effects of gonadal steroids on peripheral benzodiazepine receptor density in women with PMS and controls

BACKGROUND

GABA receptor-modifying neurosteroids may play a role in premenstrual syndrome (PMS). The peripheral benzodiazepine receptor (PBR) both regulates the formation of neurosteroids and is, in animals, regulated by ovarian steroids. Alterations in PBR density have been observed in association with several psychiatric disorders.

METHODS

We examined the effects of gonadal steroids on lymphocytic PBR density in nine women with prospectively confirmed PMS and nine controls. PBR densities were measured during three pharmacologically controlled conditions: gonadotropin releasing hormone agonist (Lupron)-induced hypogonadism, Lupron plus estradiol, and Lupron plus progesterone replacement. Blood samples were obtained after six weeks of Lupron alone and after 3-4 weeks of estradiol and progesterone replacement.

RESULTS

No significant hormone state-related changes in PBR density were observed (ANOVA-R: phase-F(2,32)=1.5, P=0.2). Despite mood symptom development in the subjects with PMS, PBR density did not differ in women with PMS compared to controls across hormonal states (ANOVA-R: F(1,16)=0.6, P=0.4).

CONCLUSIONS

PBR densities are not altered in women with PMS and are not changed significantly by selective gonadal steroid administration. Changes in PBR density would not appear to underlie the differential sensitivity to the mood destabilizing effects of ovarian steroids in PMS.

Valvular heart operation in patients with previous mediastinal radiation therapy

BACKGROUND

The outcome of valvular heart operations in patients with previous mediastinal radiation therapy was studied.

METHODS

This is a single center retrospective study of 60 patients (37 females, 23 males) with a mean age of 62 +/- 15 years (28 to 88 years old) operated on from January 1976 to December 1998. Valvular heart operations performed included aortic valve replacements (n = 26), mitral valve procedures (n = 16), tricuspid valve procedures (n = 6), and multiple valve procedures (n = 12). A total of 264 clinical, hemodynamic, electrocardiographic and echocardiographic variables were analyzed.

RESULTS

Total follow-up was 199 patient-years with a mean of 3.3 +/- 3.1 years and a range of 0 to 12.4 years old. Early mortality was 7 patients (12%). Early mortality in patients with constrictive pericarditis was 40% (4 of 10) compared with 6% (3 of 50) in patients without constrictive pericarditis. By univariate analysis, early mortality was associated with constrictive pericarditis (p = 0.011), reduced preoperative ejection fraction (p = 0.015), and longer cardiopulmonary bypass times (p = 0.037). A total of 14 patients (23%) required permanent pacemaker placement before (n = 7), during (n = 1), or early (n = 6) after valvular heart operations. There were 19 late deaths (malignancies, 7; heart failures, 5; other cardiac, 4; and other noncardiac, 3). Overall survival and freedom from late cardiac death and cardiac reoperation at 5 years for hospital survivors were 66% +/- 8%, 82% +/- 7%, and 93% +/- 4%, respectively. By univariate analysis, late cardiac death was associated with low ejection fraction (p = 0.002), New York Heart Association (NYHA) functional class IV (p = 0.004), preoperative congestive heart failure (p = 0.02), and preoperative atrial fibrillation (p = 0.038). Eighty-five percent of the discharged patients were in NYHA functional class I or II at follow-up.

CONCLUSIONS

Early results of valve replacement after mediastinal radiation therapy were good except in the presence of constrictive pericarditis. Long-term outcome was limited by malignancy and heart failure. Early surgical intervention is recommended before the development of risk factors for late death, namely, severe symptoms, left ventricular dysfunction, and atrial fibrillation.