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From November, 1973, through June, 1978, 428 operations in 425 patients were performed for replacement of aortic, mitral, or aortic plus mitral valves, utilizing 277 Hancock and 180 Carpentier-Edwards bioprostheses. Actuarially determined survival at 36 months was similar for all three groups and compared favorably with our experience with the Björk-Shiley prosthesis. Certain patient-related variables influencing late survival were identified by multivariate analysis and included previous operation for congenital heart disease, coronary artery bypass grafting in nonaortic valve replacement, race (black), age at operation, and New York Heart Association Functional Class. A small but definite incidence of thromboembolism occurred in all three groups, again similar to our experience with the Björk-Shiley prosthesis. Multivariate analysis identified four factors influencing risk of thromboembolism: previous cardiac operation, age, double-valve replacement, and rhythm at discharge. Valve degeneraation occurred, primarily in children and young adults. Over the medium term, the porcine bioprosthesis compared favorably with mechanical prostheses in terms of survival, function, and thromboembolism. Certain patient-related variables affecting survival may be modified by earlier surgical intervention.

Abstract Background Mycobacterium avium subsp. paratuberculosis (MAP) is the cause of Johne’s disease, an enteric granulomatous disease. Recently, MAP has been associated with different autoimmune diseases such as Crohn’s disease, type 1 diabetes (T1D) and multiple sclerosis. Transthyretin (TTR) is a plasma transport protein for thyroid hormone and forms a complex with retinol-binding protein. Reduced TTR plasma levels in MAP infected ovines have been reported. TTR exerts also a functional role in the pancreas promoting insulin release and protecting β-cells from death. Our objective was to identify a protein that could be used as a diagnostic marker of T1D for determining disease progression and monitoring at-risk patients. We postulate that serological TTR levels would be reduced in T1D MAP exposed patients. Our hypothesis is based on the observation of cases of T1D patients with decreased TTR levels beside the reduced TTR plasma levels in ovines with Johne’s disease. We quantified the plasma protein levels of TTR in 50 people with T1D and 51 age-matched healthy controls (HCs) by means of enzyme-linked immunosorbent assays (ELISA). Findings Our pilot study showed that plasma TTR levels were not significantly lower/higher in T1D Sardinian cases compared to the HCs. Conclusion These preliminary data indicate that plasma TTR may not be a good candidate biomarker for T1D diagnosis and further studies to elucidate the possible link are needed.

Abstract Background The role of pathogenic mycobacteria in diabetes has been a focus of speculation since a decade without any meaningful insights into the mechanism of diabetes causation vis a vis mycobacterial factors. Two of our studies based on PCR identification of mycobacterial DNA and detection of antibodies specific to the recombinant antigens and whole cell lysates of the Mycobacterium avium subsp. paratuberculosis (MAP) shown a clear association of MAP with the presence of type 1 diabetes mellitus (T1DM). Methods In this study, we sought to investigate if or not type 2 diabetes (T2DM) patients harbour humoral responses to MAP. Using three different MAP antigen preparations, humoral antibody profiles were estimated for 57 T2DM patients and 57 healthy controls. Statistical analysis was performed with the Chi-square test with Yates' corrections. Results We observed insignificant levels of humoral antibodies against recombinant heparin binding haemagglutinin (HbHA), glycosyl transferase (Gsd) and MAP whole cell lysate in the blood of subjects with T2DM as compared to healthy controls. Conclusion We found no obvious association of MAP with the incidence of T2DM in Sardinian patients.

Abstract Background The Mediterranean island of Sardinia has a strikingly high incidence of the autoimmune disorders Type 1 Diabetes (T1D) and Multiple Sclerosis (MS). Furthermore, the two diseases tend to be co-inherited in the same individuals and in the same families. These observations suggest that some unknown autoimmunity variant with relevant effect size could be fairly common in this founder population and could be detected using linkage analysis. Methods To search for T1D and MS loci as well as any that predispose to both diseases, we performed a whole genome linkage scan, sequentially genotyping 593 microsatellite marker loci in 954 individuals distributed in 175 Sardinian families. In total, 413 patients were studied; 285 with T1D, 116 with MS and 12 with both disorders. Model-free linkage analysis was performed on the genotyped samples using the Kong and Cox logarithm of odds (LOD) score statistic. Results In T1D, aside from the HLA locus, we found four regions showing a lod-score ≥1; 1p31.1, 6q26, 10q21.2 and 22q11.22. In MS we found three regions showing a lod-score ≥1; 1q42.2, 18p11.21 and 20p12.3. In the combined T1D-MS scan for shared autoimmunity loci, four regions showed a LOD >1, including 6q26, 10q21.2, 20p12.3 and 22q11.22. When we typed more markers in these intervals we obtained suggestive evidence of linkage in the T1D scan at 10q21.2 (LOD = 2.1), in the MS scan at 1q42.2 (LOD = 2.5) and at 18p11.22 (LOD = 2.6). When all T1D and MS families were analysed jointly we obtained suggestive evidence in two regions: at 10q21.1 (LOD score = 2.3) and at 20p12.3 (LOD score = 2.5). Conclusion This suggestive evidence of linkage with T1D, MS and both diseases indicates critical chromosome intervals to be followed up in downstream association studies.

In this report, we present 34 patients in whom surgical intervention was undertaken for severe mitral insufficiency due to mitral valve prolapse (MVP). Location and severity of MVP and regurgitation were assessed preoperatively by live/real time three-dimensional transthoracic echocardiography and closely agreed with the surgical findings.

In this report, we present 12 patients (range 14-76 years, mean 40 +/- 22.7 years) who underwent surgical repair of a ventricular septal defect (VSD). Location, size, and surrounding anatomy of the VSD were assessed prior to intervention in all patients with live/real time three-dimensional transthoracic echocardiography (3DTTE). In 9 patients, measurements of maximum dimension, circumference, and area by 3DTTE correlated well with the same measurements from intraoperative three-dimensional transesophageal echocardiographic (3DTEE) reconstruction. 3DTTE measurement of maximum dimension of VSDs also agreed well with maximum dimension by surgery in 10 patients. Live/real time 3DTTE accurately defined VSD location, size, and surrounding anatomy in all patients studied by us. VSD characterization by live 3DTTE agreed well with surgery descriptions and 3DTEE measurements.

This preliminary study demonstrates the superiority of live three-dimensional transthoracic echocardiography (3D TTE) over two-dimensional (2D) TTE in the assessment of left atrial (LA) tumors in four patients studied by us (three myxomas, one hemangioma, all subsequently pathologically proven). Because of the unique ability of live 3D TTE to systematically section and view the contents of an intracardiac mass, LA myxomas in the three patients studied could be more confidently diagnosed by noting isolated echolucent areas consistent with hemorrhage/necrosis in the tumor mass. On the other hand, a definite echolucent area was found by 2D TTE in only two of the three patients with myxoma. In the fourth patient with a hemangioma, live 3D TTE showed much more extensive and closely packed echolucencies with little solid tissue as compared to a myxoma consistent with a highly vascularized tumor. In contrast, 2D TTE demonstrated only two isolated echolucencies in the tumor suggesting an erroneous diagnosis of myxoma.

In this report we present 12 adult patients in whom surgical or percutaneous intervention was considered for repair of atrial septal defect (ASD). Location, size, and surrounding atrial anatomy of the ASD were assessed prior to intervention in all patients with standard and live three-dimensional transthoracic echocardiography (3D TTE). In the four patients in whom intraoperative three-dimensional transesophageal echocardiographic reconstruction (3D TEE) was done, 3D TTE measurements of maximum dimension, maximum circumference, and maximum area of ASD agreed well with 3D TEE. In the seven patients who underwent transcatheter closure device insertion, live 3D TTE measurements of maximum dimension, maximum circumference, and maximum area of ASD agreed well with the sizing balloon. Additionally, since the sizing balloon measures a stretched diameter and area, a live 3D TTE stretched ASD diameter and area (derived from the actual live 3D TTE maximum circumference) were calculated and demonstrated improved agreement with the sizing balloon measurements. In all patients, > or =5 mm of atrial tissue was visualized surrounding the ASD. Further, with the addition of contrast enhancement, characterization of a small patent foramen ovale (<5 mm) was possible in one patient. Live 3D TTE accurately defined ASD location, size, and surrounding atrial anatomy in all patients studied by us. ASD characterization by live 3D TTE agreed well with 3D TEE and sizing balloon measurements.

We evaluated 44 consecutive patients who underwent standard two-dimensional (2D) and live three-dimensional (3D) transthoracic echocardiography (TTE), as well as left heart catheterization with left ventriculography. Mitral regurgitant vena contracta area (VCA) was obtained by 3D TTE by systematic and sequential cropping of the acquired 3D TTE data set. Assessment of mitral regurgitation (MR) by ventriculography was compared to measurements of VCA by 3D TTE and to 2D TTE measurements of MR jet area to left atrial area (RJA/LAA), RJA alone, vena contracta width (VCW), and calculated VCA. VCA from 3D TTE closely correlated with angiographic grading (rs=0.88) with very little overlap. VCA of <0.2 cm2 correlated with mild MR, 0.2-0.4 cm2 with moderate MR, and >0.4 cm2 with severe MR by angiography. Ventriculographic grading also correlated well with 2D TTE measurements of RJA/LAA (rs=0.79) and RJA alone (rs=0.76) but with more overlap. Assessment of VCW and calculated VCA by 2D TTE agreed least with ventriculography (rs=0.51 and rs=0.55, respectively). Live 3D TTE color Doppler measurements of VCA can be used for quantitative assessment of MR and is comparable to assessment by ventriculography.

Aortic valve stenosis (AS) severity can be estimated by various modalities. Due to some of the limitations of the currently available methods, the usefulness of live three-dimensional transthoracic echocardiography (3D TTE) in the assessment of AS was explored. Live 3D TTE was able to visualize the aortic valve orifice in all 11 patients studied. Live 3D TTE correctly estimated the severity of AS in all 10 patients in whom AS severity could be evaluated at surgery. These included eight patients with severe AS and two with moderate AS. Two of these 10 patients with AS had associated hypertrophic cardiomyopathy and underwent myectomy at the time of aortic valve replacement. Aortic valve orifice area measurements by live 3D TTE correlated well with intraoperative three-dimensional transesophageal echocardiographic reconstruction measurements (r=0.85) but not as well with two-dimensional transesophageal echocardiography measurements (r=0.64). Live 3D TTE measurements of the aortic valve orifice area also did not correlate well with two-dimensional transthoracic echocardiography measurements (r=0.46) but the number of patients studied with two-dimensional transthoracic echocardiography was smaller (only seven) and four of these did not undergo two-dimensional transthoracic echocardiography at the authors' institution. Altogether, four patients with severe AS by live 3D TTE, and subsequently confirmed at surgery, were misdiagnosed as having moderate AS by two-dimensional transthoracic echocardiography. Because it is completely noninvasive and views the aortic valve in three dimensions, 3D TTE could be a useful complement to the existing modalities in the evaluation of AS severity., (Copyright 2004 Le Jacq Communications, Inc.)

The Sulzer Carbomedics prosthetic heart valve (CP) is a commonly used mechanical valve in clinical practice. In the present study, we used conventional and color Doppler echocardiography to assess the hemodynamics of normally functioning CP in the aortic (n = 73) and mitral (n = 127) positions. Our findings demonstrate no significant correlation of Doppler-measured peak and mean pressure gradients and effective orifice area with implanted valve size and actual orifice areas, measured directly by the manufacturer for CPs in both the mitral and aortic positions. However, it is still useful to measure effective orifice area by Doppler because a value in the normal or nonstenotic range points to an unobstructed prosthesis in the aortic or mitral position, in the absence of poor left ventricular ejection fraction. A value in the stenotic range could mean a normally functioning or obstructed prosthesis and, therefore, may need further investigation, such as assessment of valve leaflet motion by transthoracic or transesophageal echocardiography or fluoroscopy. Valve regurgitation as evaluated by color Doppler flow mapping was mild in practically all CPs in the aortic position, and in the majority of CPs in the mitral position.

We report three-dimensional transesophageal echocardiographic findings in an adult patient with Ebstein's anomaly. Using the anyplane technique and multiple views, especially the short-axis view of tricuspid valve, three-dimensional transesophageal echocardiography clearly demonstrated the intermittent tethering of all three leaflets of tricuspid valve to the right ventricular walls giving a "bubble-like" appearance. On the other hand, two-dimensional transesophageal echocardiography demonstrated well the tethering of the septal tricuspid leaflet, but tethering of the other two leaflets was not well seen. To our knowledge, these findings have not been demonstrated by three-dimensional transesophageal echocardiography before.

We evaluated the potential usefulness of three-dimensional (3D) transesophageal echocardiography (TEE) in assessing individual scallop/segment prolapse in 36 adult patients with mitral valve prolapse (MVP) undergoing surgical correction. Intraoperative 3D TEE correctly identified the location of scallop/segment prolapse in 34 of 36 patients (94%). However, in 6 of these patients 3D TEE images revealed more scallops or segments with prolapse than the surgeon noted intraoperatively. Prolapse of these areas was less prominent and this could possibly explain the lack of correlation with the surgical findings in these patients. In another 2 patients areas of prolapse seen by the surgeon were missed by 3D TEE because some of those scallops/segments could not be well imaged due to image "drop out" and artifacts. Thus, perfect correlation between 3D TEE and surgery was noted in 28 of 36 (78%) patients. Noncoaptation of the MV was also identified in 2 patients. The prolapsed area of posterior (n = 28 observations) and anterior (n = 9 observations) MV leaflets ranged from 1 cm2 to 9 cm2 (mean 3.50 cm2+/- 2.14) and 1.20 cm2 to 5.99 cm2 (mean 3.21 cm2+/- 1.33), respectively. Interobserver and intraobserver agreement for location and area of MVP was excellent (r = 0.97 and r = 0.99, respectively; all P values are <0.0001). In conclusion, 3D TEE is useful in identifying the location of MVP. It may also be potentially useful in assessing the extent of individual scallop/segment prolapse and identifying sites of MV noncoaptation. This information could aid the surgeon in deciding the extent of MV resection.

We present two- and three-dimensional transesophageal echocardiographic findings of two adult patients who presented for reoperation after previous repair of a partial atrioventricular (AV) septal defect. Both patients had a cleft in the left AV valve with severe regurgitation. One patient had an additional 10 x 5 mm defect connecting the left ventricle to the right atrium through the AV junction. Three-dimensional echocardiography was superior to two-dimensional echocardiography in comprehensively delineating the anatomical defects in the left AV valve and the AV junction.

Pulmonary vasospasm and hypertension may occur after repair or palliation of congenital cardiac defects, and can be fatal in spite of conventional treatment. Nitric oxide has been shown to improve pulmonary hypertension unresponsive to conventional measures after a variety of repairs, but use has infrequently been reported after palliative systemic to pulmonary artery shunts. We report a case of pulmonary hypertension and life threatening desaturation after a modified Blalock-Taussig shunt that responded rapidly to inhaled nitric oxide. Clinical use, further study, and prospective analysis of prophylactic use of nitric oxide appear warranted.

As compared with two-dimensional (2-D) transesophageal echocardiography (TEE), 3-D echocardiography now permits more realistic visualization of cardiac anatomy and of intracardiac lesions. The aim of this study was to apply newer 3-D echocardiographic techniques to quantify volumes of intracardiac masses undergoing surgical resection seen during an intraoperative TEE. The calculated volumes were compared with actual in vitro measurements of surgically resected masses. A total of 14 patients (9 men; 5 women; age range between 21 and 77 years) with intracardiac mass lesions (4 tumors: 3 left atrial myxomas and 1 mitral valve fibroelastoma, and 10 vegetations: 5 aortic valve, 3 mitral valve, 1 tricuspid and 1 pulmonary valve) were studied. Using commercially available 3-D reconstruction software (TomTec v. 4.1), the volumes of intracardiac masses were estimated using both the average rotation (rotation around the long axis, AR) and disk summation (parallel short axis cuts, DS) methods. Volumes of these lesions were also measured in vitro by water submersion. They ranged from 0.20 mL to 24 mL (mean +/- SD = 8.07 +/- 9.21 mL). Both 3-D TEE AR and 3-D TEE DS calculated volumes correlated excellently with in vitro measured volumes (r = 1.00 and r = 0.98, respectively, p = < 0.0001). The correlation between 3-D TEE AR and 3-D TEE DS calculated volumes was also excellent (r = 0.98, p = < 0.0001). In conclusion, the volume assessments by 3-D TEE of intracardiac mass lesions correlated well with in vitro measured volumes of surgical specimens. This technique may prove to be valuable in further defining intracardiac pathology and is a further advancement toward the application of clinically useful 3-D echocardiography.

In a prospective study, the etiology of community-acquired pneumonia (CAP) was investigated among consecutive patients admitted to an academic, urban public hospital in Seattle. The study population was uniquely young, was predominantly male, and had high rates of homelessness, cigarette smoking, alcoholism, injection drug use, and human immunodeficiency virus (HIV) infection. Leading causes of CAP among HIV-negative patients were aspiration, followed by Streptococcus pneumoniae, Legionella species, and Mycoplasma pneumoniae. Among HIV-positive patients, Pneumocystis carinii, Mycobacterium tuberculosis, S. pneumoniae, and M. pneumoniae were the most common etiologic agents. Severe CAP was associated with typical bacterial infections and aspiration pneumonia but not Legionella infection among HIV-negative patients and with Pseudomonas aeruginosa infections among HIV-positive patients. These findings emphasize the need to tailor empirical antibiotic therapy according to local patient populations and individual risk factors and highlight the importance of recognizing underlying HIV infection in patients who are hospitalized with CAP.

We present a patient in whom the exact location of a right atrial lipoma identified with two- and three-dimensional transesophageal echocardiography (2-D and 3-D TEE) was correlated with the surgical findings. By orienting the 3-D TEE images to conform to the view of the surgeon from the right side of the patient and referencing the site of attachment of the tumor to the surrounding structures, this lipoma was correctly localized to a 7 o'clock position in the right atrium.

Objective: The objective of this study was to determine whether preincision use of an intra-aortic balloon pump improves survival and shortens postoperative length of stay in hemodynamically stable, high-risk patients undergoing coronary artery bypass grafting., Methods: A post hoc analysis of the Alabama CABG Cooperative Project database was performed by using propensity scores to model the likelihood of receiving a prophylactic preincision intra-aortic balloon pump. Every patient receiving a prophylactic preincision balloon pump was matched with another patient of similar propensity score who did not receive one. We then compared outcomes for matched pairs., Results: There were 7581 patients of whom 592 received a prophylactic preincision balloon pump. Patients with preoperative renal insufficiency, heart failure, or left main coronary artery disease, or who had undergone previous bypass grafting were significantly more likely to receive a prophylactic preincision balloon pump. By using propensity scores, we matched 550 patients who received a prophylactic preincision balloon pump with 550 who did not. Survival did not significantly differ by whether a prophylactic preincision balloon pump was used. However, surviving patients who received a preincision balloon pump had a significantly shorter postbypass length of stay (7 +/- 7.3 days) than did matched patients not receiving a balloon pump (8 +/- 6.2 days; P <.05)., Conclusions: No survival advantage was found for use of a prophylactic intra-aortic balloon pump in hemodynamically stable, high-risk patients undergoing bypass grafting, as opposed to placing a balloon pump on an "as needed" basis during or after the operation. However, the patients receiving the balloon pump had improved convalescence as shown by significantly shorter length of stay.

Background: This report describes technical details of the right thoracotomy approach for mitral surgery, and analyzes our experience with this procedure for patients with a prior sternotomy. Three methods for myocardial management (hypothermic cardioplegic arrest, beating heart, and fibrillating heart) are compared., Methods: Records were abstracted of patients who had a right thoracotomy between January 1, 1992 and July 1, 1999 for mitral surgery after at least one prior sternotomy. Demographic, operative, and outcome data were collected for analysis. Telephone follow-up was used to measure postoperative New York Heart Association functional status., Results: Eighty-four patients (mean age 60 +/- 15 years) had reoperative mitral surgery via a right thoracotomy. Myocardial management included ventricular fibrillation in 10 patients, operation on the beating heart in 58 patients, and hypothermic blood cardioplegia arrest in 16 patients. The mean time in the operating room was 185 +/- 73 minutes, and the mean duration of cardiopulmonary bypass was 63 +/- 56 minutes. There were no perioperative strokes and the prevalence of death for patients who received cardioplegic arrest was significantly higher than the prevalence of death for patients who had mitral surgery with perfused fibrillating or beating heart techniques (p = 0.007; Fisher's exact test comparing risk-unadjusted mortality)., Conclusions: Right thoracotomy provides efficient exposure for reoperative mitral surgery. Mitral valve procedures on the fibrillating or beating heart are feasible in most patients and are at least as safe as surgery using cardioplegic arrest.

The incremental value of three-dimensional echocardiography over transesophageal multiplane two-dimensional imaging in the assessment of sinus venosus atrial septal defect is demonstrated in the present study.

Background and Objective: Cardiac disease is a common cause of death in renal transplant recipients. This study retrospectively analyzes the results of myocardial revascularization procedures in these patients and makes recommendations for managing coronary atherosclerosis in patients with renal disease who already have a transplanted kidney or who may receive a kidney transplant., Methods: Patients who had myocardial revascularization (coronary artery bypass grafting [CABG] or percutaneous transluminal coronary angioplasty [PTCA]) and renal transplantation at the authors' institution between 1968 and 1994 were analyzed. Patient, procedural, and institutional variables were used for actuarial analyses of survival, as well as multivariate analyses of risk factors for death., Results: Eighty-three of 2989 renal transplant patients required myocardial revascularization either before or after their transplant, and diabetes mellitus was the cause of renal failure in 42% of these patients. Standard coronary angiography, CABG, and PTCA techniques were used without periprocedural renal allograft loss. Actuarial patient survival was 89%, 77%, and 65% at 1, 3, and 5 years after the last procedure (transplantation or revascularization). Cardiac disease was the most common mode of death. Early-phase risk factors for death by multivariate analysis included hypertension and revascularization before 1989. Late-phase risk factors for death included diabetes mellitus, higher number of pre-CABG myocardial infarctions, renal transplantation before 1984, older age, and unstable angina before CABG., Conclusions: Myocardial revascularization can be performed with acceptable short- and long-term results in patients with renal disease who have renal transplantation either before or after the revascularization procedure. Diabetes mellitus was a highly prevalent condition among these patients, and cardiac disease was their most common mode of death. PTCA and CABG, as performed at this institution, posed little risk for renal allograft loss. Modification of risk factors for coronary atherosclerosis, rigorous cardiac evaluation of patients at risk for coronary artery disease before renal transplantation, and aggressive use of revascularization procedures to decrease the incidence of myocardial infarction are proposed as ways to prolong the survival of renal transplant patients with ischemic heart disease.

Background: Air leaks (ALs) are a common complication after pulmonary resection, yet there is no consensus on their management., Methods: An algorithm for the management of chest tubes (CT) and ALs was applied prospectively to 101 consecutive patients who underwent elective pulmonary resection. Air leaks were graded daily as forced expiratory only, expiratory only, inspiratory only, or continuous. All CTs were kept on 20 cm of suction until postoperative day 2 and were then converted to water seal. On postoperative day 3, if both a pneumothorax and AL were present, the CT was placed to 10 cm H2O of suction. If a pneumothorax was present without an AL, the CT was returned to 20 cm H2O of suction. Air leaks that persisted after postoperative day 7 were treated with talc slurry., Results: There were 101 patients (67 men); on postoperative day 1, 26 had ALs and all were expiratory only. Univariable analysis showed a low ratio of forced expiratory volume in 1 second to forced vital capacity (FEV1/FVC) (p = 0.005), increased age (p = 0.007), increased ratio of residual volume to total lung capacity (RV/TLC) (p = 0.04), increased RV (p = 0.02), and an increased functional residual capacity (FRC) (p = 0.02) to predict the presence of an AL on postoperative day 1. By postoperative day 2, 22 patients had expiratory ALs. After 12 hours of water seal, 13 of the 22 patients' ALs had stopped, and 3 more sealed by the morning of postoperative day 3. However, 2 of the 6 patients whose ALs continued experienced a pneumothorax. Five of the 6 patients with ALs on postoperative day 4 still had ALs on postoperative day 7, and all were treated by talc slurry through the CT. All ALs resolved within 24 hours after talc slurry., Conclusions: Most ALs after pulmonary resection are expiratory only. A low FEV1/FVC ratio, increased age, increased RV/TLC ratio, increased RV, and an increased FRC were predictors of having an ALs on postoperative day 1. Conversion from suction to water seal is an effective way of sealing expiratory AL, and pneumothorax is rare. If an expiratory AL does not stop by postoperative day 4 it will probably persist until postoperative day 7, and talc slurry may be an effective treatment.

Background: Cardiac surgical patients consume a significant fraction of the annual volume of allogeneic blood transfused. Scavenged autologous blood may serve as a cost-effective means of conserving donated blood and avoiding transfusion-related complications., Methods: This study examines 834 patients after cardiac operations at the University of Alabama Hospital. Data were collected on patients receiving unwashed, filtered, autologous transfusions from shed mediastinal drainage and those receiving allogeneic transfusions. The data were incorporated into clinical decision models; confidence intervals for parameters were estimated by bootstrapping sample statistics. Costs were estimated for transfusing both allogeneic and autologous blood., Results: The study found a 54% reduction in transfusion risk or a mean reduction of 1.41 allogeneic units per case (95% confidence interval, 1.04 to 1.79 units). The process saved between $49 and $62 per case., Conclusions: The use of autologous blood has the potential to significantly reduce the costs and risks associated with transfusing allogeneic blood after cardiac operations.

The diagnosis and site of graft dehiscence determined by transesophageal echocardiography (TEE), transthoracic echocardiography (TTE), and aortography in 6 patients, and by computed tomography (CT) scan in 3 patients were compared with surgery. Sensitivity of TEE was 100%, aortography 83%, CT scan 67%, and TTE 33%; TEE accurately identified severe aortic regurgitation (3), graft narrowing (2), distal aortic dissection (1), and a fistulous communication between the aortic root and the right ventricle (1) when compared with surgery or aortography.

We describe our preliminary experience in assessing normal and stenosed coronary arteries using transesophageal three-dimensional echocardiography (3-D echo) in 27 adult patients. Multiplane transesophageal two-dimensional images of the coronary arteries (20 left, 3 right, 3 both left and right, and 1 posterior descending) were first acquired in the TomTec computer in 3 degrees sequential increments, from 0 degrees to 180 degrees, and then 3-D reconstruction was performed. The entire left main (LMC, measuring 0.5 to 1.7 cm, mean 1.0 cm) as well as variable lengths of proximal or both proximal and middle segments of the left anterior descending (LAD, measuring 0.2 to 2.5 cm, mean 0.8 cm) and circumflex (LCX, measuring 0.2 to 2.8 cm, mean 0.9 cm) coronary arteries together with some of their branches could be visualized in 3-D in 22 of 23 patients. In the remaining patient, the LMC was absent, and both LAD and LCX could be visualized in 3-D as having separate but adjacent origins from the left sinus of Valsalva (proven by angiography). In two patients, long segments of interventricular and great cardiac veins were also visualized accompanying the LAD and LCX, respectively. The right coronary artery (RCA, measuring 0.7 to 3.0 cm, mean 1.9 cm) was also successfully delineated in 3-D in all six patients in whom an attempt was made to visualize it during echo examination. Using the transgastric approach, a long (1.8 cm) segment of the posterior descending branch (PDA) of RCA was imaged in one patient. In addition, nine significantly stenotic lesions (>50% lumen diameter) were identified by 3-D in eight patients involving LMC (1), proximal LAD (1), mid LAD (1), proximal LCX (2), proximal RCA (3), and mid PDA (1). Eight of these 9 lesions were confirmed by coronary angiography. The remaining lesion (mid PDA) could not be confirmed since the patient did not undergo angiography. Our preliminary study demonstrates the usefulness of transesophageal 3-D echo not only in delineating normal coronary arteries but also diagnosing significant atherosclerotic stenosis in these vessels. (ECHOCARDIOGRAPHY, Volume 13, September 1996)

Prostaglandin E1 (PGE1) causes skeletal hypertrophy, a phenomenon noted when it is administered for several weeks to maintain ductus arteriosus patency in neonates with congenital heart disease. This effect, a dose-dependent and reversible hyperostosis, was described radiologically as bone within bone, but skeletal histopathology was not studied. We compared postmortem gross, radiological, and histological bone findings for untreated controls and term gestation infants after 4, 27, and 56 days of continuous 0.1-0.2 microgram/kg/min PGE1. Bone was not significantly different from controls after 4 days of PGE1. Radiographs were negative after 27 days, but femoral cortex showed early periosteal osteoblast proliferation. At 56 days of PGE1, there was severe, radiologically apparent neocortex formation in tubular, rib, and scapular bones. Corresponding sections of femoral shaft revealed distinctive histopathology with thickened periosteum and fibrocartilage-like tissue covering an exuberant neocortex of closely aligned, gracile, woven bone trabeculae. Paratrabecular stroma contained ectatic capillaries orthogonally oriented to the periosteum, suggesting that a vascular reaction to PGE1 is important in the observed effect. The native cortex was partially resorbed; because it is stress shielded by the neocortex and no inflammation was present, this was interpreted as a secondary effect. We conclude that PGE1-associated paracortical bone hypertrophy is distinct from inflammatory processes and that its early stages may not be apparent radiologically. Moreover, the time course of PGE1-induced osteoblast proliferation and mineralization suggests that experimental use for 4-8 weeks may benefit conditions such as ununited fractures.

Background: Intravascular perfluorochemical emulsions together with a high oxygen tension may increase the delivery of dissolved oxygen to useful levels. The hypothesis of this study is that increasing the dissolved oxygen content of blood with incremental doses of a perfluorochemical emulsion improves tissue oxygenation during cardiopulmonary bypass in a dose-related fashion., Methods and Results: Oxygen utilization was studied in a profoundly anemic canine model of hypothermic cardiopulmonary bypass. Forty-two dogs underwent normovolemic hemodilution to a hematocrit of 15.8% +/- 0.6% (mean +/- standard error of the mean). Cardiopulmonary bypass was begun and resulted in a hematocrit of 9.4% +/- 0.6%. A standard priming solution was used in the control group (n = 12), and the test groups received 1.35 gm perfluorochemical.kg-1 (n = 10 dogs), 2.7 gm perfluorochemical.kg-1 (n = 10 dogs), or 5.4 gm perfluorochemical.kg-1 (n = 10 dogs) through the venous return cannula. Each animal underwent a series of randomized pump flows (0.25, 0.5, 1.0, 1.5, 2.0, and 3.0 L.min-1.m-2) at 32 degrees C. After the randomized flows were completed at 32 degrees C, the temperature was raised to 38 degrees C and cardiopulmonary bypass was discontinued. Mortality from cardiac failure on separation from cardiopulmonary bypass was 42% in the control group and 20% in perfluorochemical-treated groups. The mean perfluorochemical dose was higher in survivors than in nonsurvivors (2.9 +/- 0.4 versus 1.3 +/- 0.5 gm perfluorochemical.kg-1; p < 0.05). No differences in oxygen consumption or transbody lactate gradient were found between groups during cardiopulmonary bypass. Analysis of mixed venous oxygen tension (a surrogate measure for tissue oxygenation) as a function of cardiopulmonary bypass flow normalized to body surface area showed that the control group had significantly lower mixed venous oxygen tension (p < 0.05) than the perfluorochemical emulsion-treated groups. Furthermore, the differences were related to the perfluorochemical emulsion dose. These differences in mixed venous oxygen tension continued after termination of cardiopulmonary bypass. The coronary sinus oxygen tension and cardiac arterial-venous oxygen content differences during and after cardiopulmonary bypass were similar among the control and perfluorochemical emulsion-treated animals. Dissolved oxygen consumption during and after cardiopulmonary bypass was calculated. Dissolved oxygen consumption increased in the perfluorochemical-treated animals in a perfluorochemical dose-related manner and was significantly higher in perfluorochemical-treated animals than in the control animals (p < 0.05)., Conclusions: Graded increases in mixed venous oxygen tension during cardiopulmonary bypass were observed in response to graded increases in the dissolved oxygen delivery. These data suggest that enhancing oxygenation with perfluorochemical-dissolved oxygen is an effective temporary substitute for the use of hemoglobin-bound oxygen during cardiopulmonary bypass. Perfluorochemical-dissolved oxygen may be particularly beneficial in the setting of multiple hypoxic stresses.

Background: Reperfusion arrhythmias that follow regional ischemia at normothermia have been studied extensively and are considered to be a manifestation of ischemia-reperfusion injury. In contrast, reperfusion arrhythmias that occur following hypothermic cardioplegic arrest have received little attention from investigators. This study defines the electrophysiological mechanisms for postcardioplegia reperfusion ventricular fibrillation (RVF)., Methods and Results: The electrophysiology of postcardioplegia RVF was examined by using in situ porcine hearts. Complete heart block was created by using cryoablation before cardioplegic arrest so that isolated ventricular electrical activity could be observed for a prolonged time after reperfusion. Electrophysiological data were collected from limb leads, right atrial electrodes, and left ventricular electrodes in all 12 pigs. In 5 pigs, right and left ventricular endocardial electrograms were also recorded. A total of 103 episodes of RVF were analyzed. In 90 instances, an accelerating automatic ventricular focus initiated RVF. In five animals, RVF occurred after ventricular pacing (ie, purely re-entrant RVF). The mechanism for RVF was indeterminant in 8 instances. The origin of RVF was mapped in 44 instances. RVF usually originated in the left ventricle (25 instances) or septum (16 instances)., Conclusions: Enhanced automaticity and re-entry are the mechanisms for postcardioplegia and regional ischemia-reperfusion arrhythmias. This finding supports the use of postcardioplegia RVF as a variable for comparing strategies for myocardial protection and suggests that information generated by the study of regional ischemia reperfusion arrhythmias can be used to understand postcardioplegia reperfusion arrhythmias and ischemia-reperfusion injury.

Background: This study compares oxyhemoglobin dissociation during the nonperfused periods of hypothermic cardioplegic arrest in two blood cardioplegic solutions with different hemoglobin concentrations. The hypothesis is that more oxygen will dissociate from hemoglobin in a blood cardioplegic solution with a higher hemoglobin content than from a cardioplegic solution with a lower hemoglobin content. However, the increment in the volume of oxygen that dissociates from hemoglobin will be less than anticipated by a ratio of hemoglobin concentrations in the cardioplegic solution., Methods and Results: Pigs (n = 22) were supported by bypass and subjected to 60 minutes of hypothermic cardioplegic arrest with either a high-hemoglobin (n = 10) or low-hemoglobin (n = 12) blood cardioplegic solution. Aortic root and coronary sinus blood samples were obtained before bypass and 5 seconds after the start of cardioplegic infusions at 20, 40, and 60 minutes of cardioplegic arrest. Oxyhemoglobin dissociation occurred in both experimental groups during the ischemic intervals of cardioplegic arrest. However, there were no significant differences between the high- and low-hemoglobin groups in the arterial-venous oxygen content differences for samples taken after each of the three ischemic intervals (p values: control = 0.78; cardioplegia interval 1 = 0.95; interval 2 = 0.56; and interval 3 = 0.12)., Conclusions: The present study emphasizes the inherent limitations of unmodified erythrocyte hemoglobin as an oxygen source in hypothermic alkalotic cardioplegic solutions. These limitations may be obviated by methods that increase the dissolved oxygen content of the cardioplegic solution or methods that decrease the affinity of hemoglobin for oxygen under conditions of hypothermia and alkalosis.

This study compared myocardial blood flow during postcardioplegia reperfusion asystole and ventricular fibrillation. Pigs (n = 20) were placed on cardiopulmonary bypass and blood cardioplegic solution at 38 degrees C was then infused. A preischemia microsphere injection was given in asystolic hearts. All animals then had 1 hour of hypothermic cardioplegic arrest and underwent reperfusion with high-dose (n = 10) or low-dose (n = 10) 38 degrees C blood cardioplegia. At 30 seconds after reperfusion, all hearts were asystolic. The second microsphere injection was then given. At 3 and 6 minutes after reperfusion, the animals' hearts were either in asystole (n = 10) or ventricular fibrillation (n = 10), and the third and fourth microsphere injections were then given. At 10 minutes after reperfusion, all hearts were beating and the final (fifth) microsphere injection was given. There was an initial increase in the global myocardial blood flow during reperfusion versus the preischemic control value. However, later, during reperfusion (ie, at the third and fourth injections), there was a significant (p < 0.05) decrease in the global myocardial blood flow. There was no discernible response in either the global myocardial blood flow or regional myocardial blood flow distribution to electromechanical activity (ie, ventricular fibrillation) for the third and fourth injections, suggesting that coronary autoregulation was abnormal. Postcardioplegia reperfusion ventricular fibrillation imposes metabolic demands that may cause reperfusion injury, especially in hearts affected by hypertrophy, ventricular distention, or coronary obstruction.

Fifty-four consecutive patients underwent aortic valve replacement with a pulmonary autograft (Ross operation) over an 18-month period. It was inserted as an intra-aortic cylinder in 13 patients and as a total aortic root replacement in 41; unwrapped in 16, partially wrapped with autologous pericardium in 12 and completely wrapped with bovine pericardium in 13. There were two cardiac deaths, one death from mediastinitis, and two early reoperations to replace an incompetent autograft. Comparison of postoperative echocardiographic data showed a higher incidence of moderate and severe autograft incompetence in the intra-aortic cylinder group and also in the subset without previous operation which had a total root replacement without a complete wrap. Autograft function was best in the group which received a total root replacement with a complete wrap and in those with previous cardiac surgery who received an unwrapped autograft. This preliminary information with short follow up supports the use of complete wrapping of the autograft when it is used as a total root replacement particularly in older patients without previous cardiac surgery in whom future autograft growth is not desirable.

The authors previously published data that describe acute alterations in ventricular dimensions and in the severity of mitral and tricuspid regurgitation (MR/TR) after initiation of left ventricular assist device (LVAD) pumping. In the current study, measurements of ventricular size and regurgitant jet area acquired after LVAD implantation are presented. Eight patients had LVAD implanted pending cardiac transplantation (duration of assist 70-279 days; mean, 162 +/- 29 days). Echocardiograms were obtained at the time of LVAD implant and later during LVAD support (mean time for late echo, 95 +/- 32 days post-implant). Comparisons of pre-implant with late post-implant data showed: increased TR jet area (4.8 +/- 1.0 cm2 vs. 8.0 +/- 1.7 cm2 P < 0.05); increased right ventricular (RV) end-systolic dimension (31 +/- 4 vs 40 +/- 5 mm, P < 0.05); and increased RV end-diastolic dimension (35 +/- 4 vs. 45 +/- 5 mm, P < 0.065). Decreased MR jet area and decreased LV dimensions (P < 0.05) also were noted on comparison of pre-implant and late post-implant data. There were no significant differences between any immediate post-implant and late post-implant echocardiographic measurements. No patient had clinical evidence of RV failure. LV mechanical assist causes an acute increase in TR, presumably by volume loading the RV. TR and RV enlargement persisted but did not discernibly worsen on subsequent post-implant echocardiograms. LV dimensions and MR remained less than the pre-implant values on later post-implant determinations.

The success of methods that ablate atrioventricular (AV) node reentry demonstrates that extranodal tissue is part of the reentry circuit. The hypothesis of this study is that atrial tissue approaching the posterior AV node is part of the AV node reentry circuit and is especially suitable for complete division with sparing of AV conduction. This study measured AV node function after either an anterior or posterior perinodal incision. The only significant change noted in antegrade function was a lengthening of the Wenckebach point after the posterior incision. Retrograde AV conduction and ventricular echoes were abolished by the posterior incision, whereas the anterior incision had no discernible effect on retrograde AV node function. Anatomic analysis of the two incisions showed that the posterior incision completely interrupted the posterior atrial input to the AV node, whereas the anterior incision spared the medial input to the AV node. The atrial tissue posterior to the AV node is anatomically suited for complete interruption. Ablation of atrial tissue posterior to the AV node is proposed for abolishing AV node reentrant tachycardia.

Stenosis of individual pulmonary veins is a rare condition associated with a very high mortality. The present report is the first known case of progressive pulmonary venous obstruction associated with the tetralogy of Fallot. This clinical and anatomical study suggests that initial dynamic and possibly reversible occlusion occurs at the junction of the pulmonary vein and left atrium. Anatomical lesions in pulmonary veins then develop, possibly secondary to functional stenosis. The usually fatal outcome of these cases is due to the development of fixed pulmonary venous occlusion and possibly pulmonary interstitial fibrosis. The rapid progression of pulmonary venous stenosis strongly suggests that discrete veno-atrial stenosis should be surgically corrected as early as possible to prevent the irreversible diffuse pulmonary venous obstruction associated with an invariably fatal prognosis.

The development of novel perfluorocarbon emulsions that contain higher concentrations of perfluorochemicals than previous emulsions has renewed interest in the use of this class of erythrocyte substitute in cardiopulmonary bypass (CPB). Perfluorocarbons have the potential to increase the oxygen content of the perfusate and thus increase the capacity of the heart-lung machine to deliver oxygen to the body during CPB. Increasing the capacity of the heart-lung machine to deliver oxygen to the body has important implications for the conduct of cardiac operations. For example, adding perfluorocarbons to the pump prime solution may allow larger volumes of blood to be withdrawn from the patient immediately prior to bypass for transfusion after bypass. Lowering the acceptable hematocrit during CPB with the use of perfluorocarbons may also decrease the need for homologous transfusions of erythrocytes in neonates or anemic adults who undergo CPB.

Background: The effects of mechanical left ventricular assist on the nonassisted right ventricle have not been fully elucidated. Current information indicates that the right ventricle benefits from a lower left atrial pressure; however, ventricular septal shifting and increased venous return caused by left ventricular assist impair right ventricular function. Acute intraoperative alterations in mitral and tricuspid valve regurgitation (MR and TR, respectively) may occur as a result of mechanical left ventricular assist but have not yet been documented., Methods and Results: Eight patients undergoing implantation of a left ventricular assist device (LVAD) as a bridge to transplantation were studied during surgery by transesophageal echocardiography. MR was present in seven of eight patients, and TR was present in eight of eight patients before LVAD implant (mean MR jet area, 10.6 +/- 2.4 cm2, mean TR jet area, 4.8 +/- 1.0 cm2). Immediately after LVAD placement, MR was still present in seven of eight patients, and TR was present in eight of eight patients (mean MR jet area, 4.2 +/- 0.9 cm2; mean TR jet area, 8.4 +/- 1.9 cm2) (P < .05 preimplant versus postimplant jet area). These changes in MR and TR were associated with a decrease in left ventricular end-systolic dimension (62 +/- 4 versus 48 +/- 3 mm) and an increase in right ventricular end-systolic dimension (31 +/- 4 versus 40 +/- 5 mm) (P < .05 preimplant versus postimplant end-systolic dimension). No patients developed progressive right ventricular failure during 70 to 279 days of LVAD support., Conclusions: Mechanical left ventricular assist causes an acute decrease in preexisting MR. However, left ventricular assist may acutely worsen TR, presumably by shifting the ventricular septum leftward and increasing venous return to the right ventricle.

The conditions of postcardioplegia reperfusion that influence cardiac electrophysiologic recovery have not yet been fully elucidated. Studies of postcardioplegia electrophysiologic recovery and reperfusion-induced arrhythmias, particularly reperfusion-induced ventricular fibrillation, are useful for improving our understanding of reperfusion injury since reperfusion-induced arrhythmias are sensitive indicators for reperfusion injury. The purpose of this study was to determine the effects of asystolic reperfusion and reperfusate electrolyte composition on postcardioplegia electrophysiologic recovery of the heart. The hypothesis tested is that the duration of asystolic reperfusion produced by a hyperkalemic reperfusate is a primary determinant for the return of cardiac electrical activity without reperfusion-induced ventricular fibrillation and that reperfusion with a hypocalcemic-hyperkalemic solution further reduces the prevalence of reperfusion-induced ventricular fibrillation by limiting myocyte calcium exposure during initial postischemic recovery. Fifty-six pigs were supported by cardiopulmonary bypass and subjected to identical conditions of hypothermic cardioplegic arrest. Reperfusion was initiated with unmodified pump blood, a hypocalcemic-normokalemic cardioplegic solution, a hyperkalemic-normocalcemic cardioplegic solution, or a hyperkalemic-hypocalcemic cardioplegic solution. The hyperkalemic-normocalcemic solution was administered at a dose of 500 ml/m2 or 1500 ml/m2. The hyperkalemic-hypocalcemic and hypocalcemic-normokalemic solutions were given only at a dose of 500 ml/m2. All cardioplegic reperfusion solutions were followed by infusion of unmodified pump blood for the remainder of the 15-minute period of controlled reperfusion. Reperfusion-induced ventricular fibrillation was less prevalent in the high-dose hyperkalemic solution group (4/12) than in the low-dose hyperkalemic solution (9/10) or unmodified pump blood (12/12) groups (p < 0.05). The transmyocardial lactate gradient at the time of initial postreperfusion electrical activity was positive (0.21 +/- 0.04 mmol/L) in the high-dose hyperkalemic group and negative (-0.05 +/- 0.09 mmol/L) in the low-dose hyperkalemic group (p < 0.05). Fibrillation was less prevalent in the hypocalcemic-hyperkalemic group (8/12) than in the other groups reperfused with cardioplegic solution at a dose of 500 ml/m2 (hypocalcemic-normokalemic, 10/10; hyperkalemic-normocalcemic, 9/10) or in the group reperfused with unmodified pump blood (12/12) (p < 0.05, hypocalcemic-hyperkalemic group versus other reperfusate groups). Reperfusion-induced ventricular fibrillation is an indicator of reperfusion injury, and in this study the conditions of reperfusion influenced the prevalence of reperfusion-induced ventricular fibrillation. Recovery of aerobic metabolism during hyperkalemia-induced asystolic reperfusion was associated with a lower prevalence of reperfusion-induced ventricular fibrillation. Combining hypocalcemia with hyperkalemia decreased the prevalence of reperfusion-induced ventricular fibrillation.

Cryopreserved aortic valve homografts have become an accepted aortic valve substitute, but long-term studies with echocardiographic assessment of valve function are largely unavailable. Between 1981 and January 1, 1991, a total of 178 patients aged 9 months to 80 years (median 46 years) underwent implantation of a cryopreserved aortic valve homograft. Serial two-dimensional Doppler echocardiographic studies were obtained in 149 patients. Overall survival was 91% at 1 year and 85% at 8 years. Survival of patients undergoing isolated primary infracoronary aortic valve replacement was 99% at 1 month and 94% at 8 years. Twelve patients underwent homograft explanation. Freedom from explantation for leaflet degeneration was 95% at 8 years. Freedom from presumed leaflet failure (valve degeneration at explantation or aortic insufficiency grade 3/4 or more without reoperation on echocardiography) was 94% at 5 years and 85% at 8 years. By multivariable analysis younger recipient age was the only risk factor identified for leaflet failure. Ninety-five percent of patients followed up for 4 or more years were in New York Heart Association class I or II.

Background: Coronary sinus effluent contains desaturated blood during the first few seconds of hypothermic cardioplegia infusion in humans. This occurs despite the high affinity of hemoglobin for oxygen at a low temperature and alkaline pH. The present study quantitates oxyhemoglobin dissociation during hypothermic cardioplegic arrest., Methods and Results: Three infusions of a 4 degrees C alkalotic blood cardioplegia solution were given into the cross-clamped aortic root during 1 hour of cardioplegic arrest. Paired aortic root and coronary sinus blood samples were obtained before and shortly after initiating cardiopulmonary bypass and at t = 5 seconds and 30 seconds during each cardioplegia infusion. Throughout the study, the hemoglobin saturation in the aortic root samples was 100%. The mean coronary sinus hemoglobin saturation at t = 5 seconds during hypothermic cardioplegia infusion ranged from 63.0% to 66.5% (p < 0.05 coronary sinus compared with aortic root samples). The coronary sinus hemoglobin saturation approximated the aortic root hemoglobin saturation at t = 30 seconds during hypothermic cardioplegia infusion. The mean PO2 of the aortic root samples ranged from 214 to 307 mm Hg during hypothermic cardioplegia infusion. The mean PO2 of the t = 5 seconds coronary sinus samples ranged from 31 to 39 mm Hg, whereas the mean PO2 of the t = 30 seconds coronary sinus samples ranged from 85 to 119 mm Hg during cardioplegia infusion (p < 0.05 coronary sinus compared with aortic root samples)., Conclusions: Oxygen dissociates from hemoglobin contained in a hypothermic, alkalotic blood cardioplegia solution during the nonperfused phase of cardioplegic arrest. However, the only oxygen delivered to the myocardium during the infusion of a hypothermic alkalotic blood cardioplegia solution is oxygen physically dissolved in the solution.