Visceral Kaposi's sarcoma associated with human herpesvirus 8 seroconversion in a heart transplant recipient

A close association between human herpesvirus-8 (HHV-8) and Kaposi's sarcoma (KS) has been shown in transplant recipients, but donor-to-recipient transmission of HHV-8 is uncommon. Herein we report a case of a heart transplant recipient who had a fatal visceral KS in association with HHV-8 seroconversion at 18 months after transplantation with a donor having positive serology discovered after transplantation.

Under-utilization of mechanical circulatory support in Canada: why and what can be done?

In October of 2002, a workshop was held as part of the Canadian Cardiovascular Congress in Edmonton, Canada, entitled "Under-Utilization of Mechanical Circulatory Support in Canada. Why and What Can Be Done?" The workshop examined various issues related to the use of mechanical circulatory support devices in the Canadian context. Representatives from all Canadian centers with active mechanical circulatory support programs were invited to participate and participants included surgeons and cardiologists, as well as other affiliated health professionals. Opinions were solicited from the workshop participants and a series of recommendations were formulated.

Severe aortic insufficiency secondary to an aortic bioprosthesis tear

A patient with a 10-year-old Medtronic Hancock II porcine aortic bioprosthesis developed severe aortic insufficiency. A transesophageal echocardiogram showed a long and mobile mass attached to the bioprosthesis which was consistent with a torn cusp. The patient underwent replacement of the prosthesis with a mechanical valve. Pathological examination showed two subacute tears arising from the same suture buttressing site. These two tears allowed a portion of the valve apparatus to prolapse.

Improved Early Survival with the Total Artificial Heart

We report our experience with the total artificial heart (TAH) to determine if outcomes have improved. Thirty-one patients received the TAH as a bridge to transplant and were divided into the two groups A (eighteen implanted in the first eight years) and B (thirteen implanted in the last eight years). Changes in management included immediate sternal closure, early extubation, delayed transplant listing, early rehabilitation, and measurement of preformed antibodies. The infection rate in B was lower than in A, both during support (31% versus 39%) and following transplant (38% versus 72%), and rejection was lower in B than in A (0% versus 44%). There was no difference in neurological events between groups; however, reopening was more frequent in B (61% versus 28%). Hospital survival increased from 61% in A to 85% in B; however, this was not statistically significant. We hypothesize that this improvement was likely due to changes in patient management.

Ventricular Assist Devices as a Bridge to Cardiac Transplantation: The Ottawa Experience

This article reports our experience with ventricular assist devices (VADs) as a bridge to cardiac transplantation. From 1991 to 2003, a total of 42 patients received a Thoratec VAD (Thoratec Laboratories Corporation Inc., Pleasanton, CA, U.S.A.) (Group T) and 12 patients received a Novacor VAD (WorldHeart Corporation, Ottawa, Canada) (Group N). Thirty Thoratec patients were transplanted compared to six in the Novacor group. Four more Novacor patients are still supported. Of the transplanted patients, 87% survived to hospital discharge in Group T and 67% in Group N. Infections affected 29% and 50% of Group T patients during support and post-transplantation, respectively, compared to 25% and 0%, respectively, in Group N. Neurologic complications affected 33% of patients in each group during support. Reopening rates for bleeding during support were 45% and 42% in Groups T and N, respectively. There were no significant differences in outcomes between the two groups. Our study demonstrated the effectiveness of VADs in bridging mortally ill cardiac patients to successful heart transplantation.

Heart Transplantation at the Ottawa Heart Institute: Comparison with Canadian and International Results

Heart transplantation has been carried out in 340 patients in Ottawa, including seventy-one who required mechanical circulatory support as a bridge to transplant. Survival in Ottawa was compared with other Canadian centers based on data from the Canadian Organ Replacement Register up to the year 2000 and with the International Society of Heart and Lung Transplantation (ISHLT) registry 2001. For survival analysis, the number of adult patients at risk at year 0 was 303 (87 transplanted from 1985 to 1990, 105 from 1990 to 1994, and 111 from 1995 to 2000). The Statistical Analysis System (SAS) life test procedure was used. Survival was not adjusted for comorbidities or heart failure class. For the year of transplant 1985-1989, one-, five-, and ten-year patient survival in Ottawa was 83%, 70%, and 60%, respectively, compared to 82%, 71%, and 54%, respectively, for Canada (Wilcoxon test, P = 0.71), and compared to one- and five-year survival for ISHLT from 1980 to 1987 at 76% and 60%, respectively. For 1990-1994, one-, five-, and ten-year patient survival in Ottawa was 88%, 81%, and 74%, respectively, compared to 80%, 71%, and 61%, respectively, for Canada (P = 0.05), and compared to one- and five-year survival for ISHLT from 1998 to 1992 at 80% and 68%, respectively. For 1995-2000, one- and five-year patient survival in Ottawa was 90% and 82%, respectively, compared to 85% and 76%, respectively, for Canada (P = 0.09), and compared to one- and five-year survival for ISHLT from 1993 to 1996 at 82% and 68%, respectively. Survival after heart transplantation in Ottawa compares favorably with Canadian and international data.

Mechanical circulatory support for adolescent patients: the Ottawa Heart Institute experience

BACKGROUND

Mechanical circulatory support devices may be used for patients with end-stage heart failure for bridging either to cardiac transplant or to recovery of the native heart. While less common in adolescents, fulminant heart failure may be rapidly fatal in these patients unless circulatory support can be instituted.

OBJECTIVES

To assess the outcomes and the utility of mechanical circulatory assist devices for children.

METHODS

A retrospective review of pediatric patients (18 years of age or younger) who underwent circulatory support at the Ottawa Heart Institute, Ottawa, Ontario, from 1992 to 2001 was performed using chart audits.

RESULTS

Seven patients (four boys, three girls) with a mean age of 14.9 +/- 0.9 years were supported with Thoratec ventricular assist devices (n=6) or a CardioWest total artificial heart (n=1). Preoperatively, the cardiac index was 1.64 +/- 0.2 L/min/m2 on one or two inotropes with ejection fractions of 11 +/- 2.2%. Mean duration of circulatory support was 59.3 +/- 17.2 days with a hospital length of stay of 89.6 +/- 12.8 days. All seven patients underwent successful transplantation and were discharged home.

CONCLUSIONS

Pediatric patients with fulminant heart failure may be bridged to cardiac transplant successfully with mechanical circulatory support devices.

[Mitral insufficiency related to a spasm of the left anterior descending artery. A case report]

We report the case of a female patient of 76 years old admitted to our hospital for a pre-operative assessment of a symptomatic mitral regurgitation (MR) whose transthoracic echocardiography revealed only a trivial regurgitation. The occurrence during hospital stay of an acute pulmonary edema contemporary to the occurrence of a huge MR permitted to suspect the diagnosis of a paroxystic ischemic MR. Angiographic and hemodynamic evaluation revealed only a non-significant atheromateous plaque located in the distal LAD. The infusion of Methylergometrine triggered a severe spasm at the site of that plaque, associated with a huge MR visualized by TTE with restricted movements of both leaflets, responsible for an acute pulmonary edema occurring on the table of the catheterization laboratory. Recovery was quickly obtained after intravenous injection of Nitroglycerin, which removed the spasm and valvular regurgitation. The diagnosis of paroxystic ischemic mitral regurgitation was confirmed and a treatment based on high dosage of calcium-blocker was decided. After a follow-up of more than one year, the patient remains asymptomatic and the regurgitation has never occurred.

Objective and noninvasive metabolic characterization of donor hearts by phosphorous-31 magnetic resonance spectroscopy

OBJECTIVE

The authors performed a multi-institutional, prospective, blind study on hearts from local donors to validate the feasibility and accuracy of the metabolic evaluation of human hearts by phosphorus-31 ( P) magnetic resonance spectroscopy (MRS) before transplantation.

METHODS

Twenty-one hearts were separated into two groups according to a transplantation score (TS) on the basis of the current clinical and echocardiographic evaluation as follows: TS1 (n=7), grafts for United Network for Organ Sharing (UNOS) 1 patients only; and TS2 (n=14), grafts suitable for UNOS 2 patients. All hearts were cold preserved with Celsior and underwent ex situ P MRS to measure ratios of various high-energy phosphate metabolites and the intracellular pH (pHi).

RESULTS

The total duration of the MRS procedure was 32 min, thereby not unacceptably increasing the total ischemic time for the transplanted grafts. Phosphocreatine (PCr) and inorganic phosphate (Pi ) was significantly different between the two groups (0.95+/-0.29 for TS1 and 2.05+/-0.74 for TS2). The difference in pHi was also significant (7.44+/-0.13 for TS1 and 7.64+/-0.19 for TS2).

CONCLUSIONS

Determination of PCr-Pi and pHi as markers of ischemic injury before transplantation can be considered as an objective and accurate criterion for the decision to accept or refuse heart grafts for transplantation.

Surface Modified Cardiopulmonary Bypass Circuits: Modifying the Inflammatory Response

As a consequence of an aging population demographic, now more than ever, researchers in cardiac surgery must focus on means to improve the methods and technologies related to cardiopulmonary bypass. This review presents a classification of the currently available options for biomaterial modification for cardiopulmonary bypass circuits. Hypotheses are given relating the mechanism of action by which some of these surfaces afford improved biocompatibility. Finally, nonpharmacologic biomaterial-independent strategies for minimizing the effects of cardiopulmonary bypass, such as the use of hemofiltration and leukocyte filtration, and the minimization of the use of cardiotomy suction blood are outlined.

Transdiaphragmatic hernia 1 year after heart transplantation following implantable LVAD

Complications after ventricular assist devices placement most frequently consist of bleeding, infection, and thromboembolic events. We describe a late complication after transplantation caused by transdiaphragmatic connection of the device placed in the abdominal position that presented as an acute pulmonary syndrome, misleading initial diagnosis.

[Heyde syndrome]

OBJECTIVE

Heyde's syndrome associates aortic stenosis and digestive hemorrhage secondary to intestinal angiodysplasia.

OBSERVATION

A 61 year-old man presented with anemia due to martial deficiency and melena, the endoscopic examination of which was negative. The existence of a tight aortic stenosis, suspected on auscultation, suggested the diagnosis of Heyde's syndrome. Angiodysplasia is revealed during oriented enteroscopy. Following valve replacement, the need for transfusion disappeared, together with the anemia.

DISCUSSION

Although some epidemiological studies deny the existence of this syndrome, the observation of authentic cases of resolution of digestive bleeding following surgical replacement of an aortic valve, such as ours, is an argument in favor of the reality of Heyde's syndrome.

Clinical outcome after repair of acute type A dissection in patients over 70 years-old

BACKGROUND

Despite current aging of patients proposed for cardiac surgery, published results of type A dissection repair in the elderly are sparse and controversial though an increased operative risk when compared to younger patients is well-documented. Whether any patient of an advanced aged suffering from acute dissection of the proximal aorta should be referred for surgery deserves specific clinical studies.

OBJECTIVE

To define factors of poor outcome after repair of type A dissection in the elderly by focusing on both early and late results.

METHOD

A retrospective study including a consecutive series of 83 patients operated on in two neighboring French university centers between 1988 and 1999 with similar outstanding methods. Complete follow-up was achieved in March 2000. Results were compared according to: (i) the presence or the absence of complications at admission; and (ii) the use of hypothermic circulatory arrest (HCA) for completion of the distal suture.

RESULTS

Mean age was 75.2+/-3.6 years (70-85). Overall operative mortality (OM) was 37.3%. OM was significantly higher (51.2 versus 23.8%, P=0.01) for patients who presented at admission any one of the following complications: tamponade, shock, endotracheal intubation upon arrival or evidence of brain, myocardial, mesenteric, renal or limb malperfusion. OM was not significantly affected by age or by the use of HCA during repair. Overall Kaplan-Meier survival was 50% at 1 year, 30% at 5 years and 13% at 10 years and was significantly lower (P=0.004) for patients who presented at least one complication at admission. Kaplan-Meier survival (excluding OM) was respectively 81, 48 and 21% and was significantly lower in case of prolonged stay in ICU (P=0.014) and for patients operated on without HCA (P=0.02).

CONCLUSIONS

Results of repair of acute type A dissections in the elderly are acceptable for uncomplicated cases at admission. Using HCA in elderly patients whenever required for appropriate repair does not worsen early or late survival.

Parsonnet's risk score predicts late survival but not late functional results after aortic valve replacement in octogenarians

BACKGROUND AND AIM OF THE STUDY

The study aim was to assess whether outcome after aortic valve replacement (AVR) in octogenarians can be anticipated by their preoperative clinical status.

METHODS

Early and late results of 101 consecutive patients operated on for AVR between 1988 and 1998 in the authors' department were reviewed. Data were compared for two patient groups determined by Parsonnet's risk score (PRS) values: group A (n = 42), PRS <30, and group B (n = 59), PRS > or =30.

RESULTS

Hospital mortality was 7.1% in group A and 16.9% in group B (p = NS). Follow up was complete (total 268 patient-years; mean 2.7 years per patient). Five- and eight-year survival rates were 76% and 39% in group A, and 57% and 16% in group B (p <0.05). Late mortality was mainly related to non-cardiac causes. Among 61 survivors on completion of follow up, functional results (mean NYHA class and mean Karnofsky score) were 1.5+/-0.8 versus 1.5+/-0.7 and 61+/-18 versus 61+/-17 in groups A and B, respectively. Among survivors, 24/31 from group A versus 22/30 from group B were still living in their own home.

CONCLUSION

These results indicated that the PRS overestimated the operative risk of AVR in octogenarians. PRS also appeared to be related to late survival in these patients, but did not predict any postoperative functional benefits.

Changing clinical presentation of Q fever endocarditis

Fifteen cases of Q fever endocarditis that occurred in 1999-2000 in southern France are described and compared with 15 cases from the same area reported in 1987. Significant decreases were found in the prevalences of heart failure, hepatomegaly, inflammatory syndrome, anemia, leukopenia, and abnormal liver function test results in patients who had Q fever endocarditis after 1997. This was probably the result of a reduction in the delay before diagnosis of the disease and of the use of novel, effective antibiotic regimens.

Local delivery of NO-donor molsidomine post-PTA improves haemodynamics, wall mechanics and histomorphometry in atherosclerotic porcine SFA

OBJECTIVES

we investigated the therapeutic effect of angioplasty with local drug delivery (LDD) of the wall-accumulating NO-donor molsidomine (M) in the superficial femoral arteries (SFA) of atherosclerotic swine.

MATERIALS AND METHODS

atherosclerotic Pietrin swines (n=14) underwent PTA-LDD-M (4 mg/2 ml) vs contralateral PTA-LDD-Placebo in the SFA using a channelled balloon angioplasty catheter. Invasive and colour Doppler energy (CDE) assessments of haemodynamics and wall mechanics were performed at 24 h (n=4) and 5 months (n=10). Immuno-histolabelling of cell proliferation and histomorphometry were serially performed in perfusion fixed SFA samples.

RESULTS

at 24 h, PCNA-positive nuclei revealed 33+/-14 and 12+/-3 proliferating cells/mm2 at placebo and molsidomine PTA-LDD sites, respectively (p<0.001). At 5 months, PTA-LDD-M vessels, compared with PTA-LDD-P, had increased compliance (66+/-9 vs 11+/-4 ml/mmHg) and lowered impedance (0.11+/-0.05 vs 0.45+/-0.14 mmHg/ml x min(-1)) (p<0.05). CDE revealed low, middle and high velocity peaks at 7.5, 20 and 35, and 8, 15 and 22 cm x s(-1) in systolic and diastolic flows, respectively; and PTA-LDD-M prevented emergence of restenosis-associated increases in low blood velocities (p<0.01). PTA-LDD-M inhibited restenotic intimal thickening and medial thinning which decreased mean lumenal diameter in placebo-treated (2.6+/-0.3) as compared to molsidomine-treated (3.4+/-0.3 mm) vessels (p<0.05).

CONCLUSIONS

in the atherosclerotic porcine SFA model, PTA-LDD with molsidomine consistently improved haemodynamic wall mechanics, lowered cell proliferation and prevented late lumen loss observed with PTA-LDD with placebo.

Hyperprocalcitonemia is related to noninfectious postoperative severe systemic inflammatory response syndrome associated with cardiovascular dysfunction after coronary artery bypass graft surgery

OBJECTIVE

To investigate the role of 3 inflammatory parameters as early markers of severe systemic inflammatory response syndrome (SIRS) induced by coronary artery bypass graft surgery.

DESIGN

Prospective study.

SETTING

University hospital.

PARTICIPANTS

Patients (n = 63) undergoing elective coronary artery bypass graft surgery with cardiopulmonary bypass.

MEASUREMENTS AND MAIN RESULTS

The American College of Chest Physicians/Society of Critical Care Medicine classification was used to diagnose SIRS. Organ system failures were used to define severe SIRS. Serum concentrations of the inflammatory parameters (procalcitonin [PCT], C-reactive protein, leukocyte count) were determined before, during, and after surgery. SIRS occurred in 30 (47%) patients after surgery. Seven patients (11%) showed SIRS with greater-than-or-equal1 organ dysfunction (severe SIRS), whereas patients without SIRS had no organ dysfunction. Significantly higher serum levels of PCT were found in patients with severe SIRS from the 6th postoperative hour until the 3rd postoperative day with a peak level of 10.7 plus minus 13.2 ng/mL. No significant difference was detected between serum PCT of patients with SIRS but without any organ dysfunction and patients without SIRS. PCT levels of these patients remained lower than 1.7 ng/mL. Compared with PCT, plasma concentrations of C-reactive protein peaked later on the 2nd postoperative day and were not able to confirm the severity of SIRS. Leukocyte counts were not significantly modified.

CONCLUSIONS

PCT seems to be an appropriate marker to identify the early development of noninfectious postoperative severe SIRS after coronary artery bypass graft surgery with cardiopulmonary bypass.

[Is chronic or recurrent idiopathic pericarditis an autonomous inflammatory disease?]

PURPOSE

Chronic pericarditis or recurrent pericarditis is mostly considered to be idiopathic even when up-to-date medical investigations are undertaken. The absence of aetiology and the associated inflammatory process are features of a common disease for internists. As there are only a few published reports on this disease, therapeutic options are not easily envisaged.

CURRENT KNOWLEDGE AND KEY POINTS

Idiopathic pericarditis and its evolution, characterized by recurrence or chronicity, has long been diagnosed and studied. Faced with a case of acute pericarditis, no clinical or biological data can preclude evolution towards a chronic or a recurrent form. The two major complications are tamponade and constriction. Classical treatment is aspirin and nonsteroidal anti-inflammatories. Steroids have a spectacular effect but steroid dependence is frequently observed. Colchicine treatment seems to be efficacious and can be used to stop steroid therapy. There are only a few published reports on the importance of immunosuppressive drugs such as azathioprine and cyclophosphamide.

FUTURE PROSPECTS AND PROJECTS

Through our own experience and literature review, we propose to consider chronic and/or recurrent pericarditis as an autonomous inflammatory disease of the pericardium. Thus, large-scale studies concerning the treatment should improve the outcome of patients.

Comparison of clinical and echocardiographic characteristics of Streptococcus bovis endocarditis with that caused by other pathogens

The aim of our study was to compare the clinical, echographic, and prognostic features of Streptococcus bovis (S. bovis) endocarditis with those caused by other streptococci and pathogens in a large sample of patients with definite endocarditis by Duke criteria, using transesophageal echocardiography. Two hundred six patients (149 men, mean age 57 +/- 15 years) with a diagnosis of infective endocarditis formed the study population. All patients underwent multiplane transesophageal echocardiography and blood cultures. Cerebral, thoracoabdominal computed tomographic scan was performed in almost all patients (95%). All patients with S. bovis endocarditis underwent colonoscopy. Incidence of S. bovis endocarditis in our sample was 19%. Patients with S. bovis endocarditis were older than other groups. Multiple valve involvement, native valves, and large vegetations (>10 mm) were more frequent in patients with S. bovis. There was a significantly higher occurrence of embolism in the S. bovis group. Splenic embolism and multiple embolisms were significantly more frequent in patients with S. bovis. Gastrointestinal lesions, anemia, and spondylitis were observed more frequently with S. bovis endocarditis. In addition to the requirement for gastrointestinal examination for S. bovis endocarditis, our study underlines the need for systematic screening for vertebral and splenic localizations, and suggests the use of early surgery to prevent the high risk of embolism in these patients.

Evaluation of endovascular techniques for creating a porcine femoral artery occlusion model

PURPOSE

To determine the optimal endovascular approach to achieve long-term occlusion of large arteries, while preserving the integrity of periarterial tissue, in an animal model of ischemia.

METHODS

Femoral artery occlusions were created in 16 pigs using detachable balloons, coils, or blinded stent-grafts. Feasibility, safety, primary and long-term success, and the degree of neovascularization were determined over a 6-month period by serial angiography and histological analyses. Four animals served as untreated controls.

RESULTS

Overall primary success for all occlusion devices was 100%. The 6-month occlusion rate using detachable balloons or coils was 33% and 0%, respectively; however, all arteries occluded with blinded stent-grafts remained obstructed to the end of the study. There was no significant difference in capillary densities and collateralization of periarterial areas when occluded arteries were compared with nonoccluded controls in the same animal. No increase in collateralization was observed following endovascular arterial occlusion.

CONCLUSIONS

Percutaneous insertion of blinded stent-grafts easily, safely, and reliably creates long-term arterial occlusion in pigs, which may make this a more appropriate model for studying the effects of angiogenic factors in vivo.

Late results of double-valve replacement with biologic or mechanical prostheses

BACKGROUND

We previously showed that the risk of reoperation for structural degeneration of bioprostheses was higher in cases involving patients older than 65 years (p = 0.003) and double-valve replacement (p = 0.02). The purpose of this study was to compare late outcome of mitral-aortic valve replacement using bioprostheses or mechanical valves.

METHODS

The bioprosthesis group included all mainland France residents (n = 48) between 55 and 65 years old operated on between 1980 and 1995 for mitral-aortic valve replacement using bioprostheses. The mechanical valve group was obtained by matching each of these patients with a patient operated on using mechanical valves at approximately the same time during the study.

RESULTS

In the bioprosthesis group, 10-year survival was 45%+/-8% versus 62%+/-7% in the mechanical valve group (not significant). The linearized reoperation rate was 6.8 per patient-year versus 1.1 per patient-year (p = 0.001), and the linearized reoperative mortality rate was 1.8 per patient-year and 0.7 per patient-year (not significant), respectively.

CONCLUSIONS

The reoperative mortality risk after mitral-aortic valve replacement using two bioprostheses does not significantly decrease overall survival after age 65 years.

RT-PCR detection of the Na,K-ATPase beta3-isoform in human heart

The Na,K-ATPase is a heterodimer composed of an alpha-catalytic and a beta-glycoprotein subunit. At present, three different alpha-polypeptides (alpha1, alpha2, alpha3) and two distinct beta-isoforms (beta1 and beta2) have been detected in human heart. The aim of the present study was to determine whether or not the beta3-isoform of the Na,K-ATPase can be detected in human heart. Using the highly sensitive method of RT-PCR, we here show that human heart expresses the beta3-isoform of the Na,K-ATPase. Given the differences in pharmacological properties of the nine different Na,K-ATPase isoenzymes (containing all combinations of the subunit isoforms), the study of beta3-isoform regulation in human heart may be of interest in understanding the altered response of human myocardium to digitalis therapy during heart failure.

Simultaneous Measurements of Arterial Diameter and Blood Pressure to Determine the Arterial Compliance, Wall Mechanics and Stresses In vivo

BACKGROUND

to develop a periarterial dimensional clip-probe which, associated with endovascular pressure measurement, real-time digital signal processing/data treatment systems, enables characterisation of the basic wall mechanics in given arterial sites.

DESIGN

experimental study.

MATERIAL

a facing pair of ultrasonic crystals was incorporated in periarterial highlight probes, made of sterilisable silicone and manufactured from computer-designed stainless steel casts. The A/D converted diameter and pressure (from an endovascular micro-tip probe) signals, triggered by the ECG, were on-line processed to provide their respective profiles during an averaged cardiac cycle, and subsequently the arterial wall physics. The technique was tested in the iliac and renal arteries in eight pigs.

RESULTS

the technique was found to indicate adequately that arterial responses to distending blood pressure, as given by Petersons modulus and relative pulsatility, were identical in renals and iliacs. In contrast, the compliance, circumferential incremental elastic modulus and midwall circumferential stress were higher in iliacs than in renals, whereas arterial stiffness of the renals surpassed that of the iliacs.

DISCUSSION

the technique with sterilisable probes produces in vivo pressure-diameter relationships, arterial compliance, and wall mechanics and stresses, whatever the arterial size. The porcine iliacs and renals are elastic and viscorigid arteries, respectively.

Mechanical circulatory support for advanced heart failure: effect of patient selection on outcome

BACKGROUND

Use of wearable left ventricular assist systems (LVAS) in the treatment of advanced heart failure has steadily increased since 1993, when these devices became generally available in Europe. The aim of this study was to identify in an unselected cohort of LVAS recipients those aspects of patient selection that have an impact on postimplant survival.

METHODS AND RESULTS

Data were obtained from the Novacor European Registry. Between 1993 and 1999, 464 patients were implanted with the Novacor LVAS. The majority had idiopathic (60%) or ischemic (27%) cardiomyopathy; the median age at implant was 49 (16 to 75) years. The median support time was 100 days (4.1 years maximum). Forty-nine percent of the recipients were discharged from the hospital on LVAS; they spent 75% of their time out of the hospital. For a subset of 366 recipients, for whom a complete set of data was available, multivariate analysis revealed that the following preimplant conditions were independent risk factors for survival after LVAS implantation: respiratory failure associated with septicemia (odds ratio 11.2), right heart failure (odds ratio 3.2), age >65 years (odds ratio 3.01), acute postcardiotomy (odds ratio 1.8), and acute infarction (odds ratio 1.7). For patients without any of these factors, the 1-year survival after LVAS implantation including the posttransplantation period was 60%; for the combined group with at least 1 risk factor, it was 24%.

CONCLUSIONS

Careful selection, specifically implantation before patients become moribund, and improvement of management may result in improved outcomes of LVAS treatment for advanced heart failure.

Clinical evaluation of heparin-coated circuits for routine coronary artery bypass grafting surgery: a prospective randomized study

The aim of this study was to demonstrate the clinical and biological benefits of heparin-coated circuits in routine coronary artery bypass grafting (CABG). A prospective, randomized study was conducted in 80 patients undergoing routine CABG. Patients were randomized to either noncoated circuits (Group 1) or heparin-coated circuits (Group 2). A complete clinical evaluation was performed preoperatively at Days 0, 1, 2, and 3 and at discharge day and combined with extensive laboratory tests for hemostasis and inflammatory response. This study did not prove any major statistically significant clinical benefit of heparin-coated circuits in low risk patients. Postoperative bleeding, significantly less in the heparin-coated group, did not decrease significantly the number of transfused patients. Biological values were not changed significantly except for factor II and monocytes, which were higher in Group 2. Heparin-coated circuits offer minimal clinical and biological benefits for routine CABG surgery. However, they may prove beneficial for complex procedures or at-risk patients.

Centrifugal pumps and heparin-coated circuits in surgical treatment of giant cerebral aneurysms

Giant cerebral aneurysms may be untreatable by conventional neurosurgical techniques. Early attempts to use circulatory assistance and deep hypothermia were abandoned due to hemorrhagic complications. More recently, interest in circulatory support for complex neurosurgical procedures has been renewed. A consecutive series of 8 patients were operated on for giant cerebral aneurysms with the combined use of deep hypothermia. The protocol included careful preoperative cardiovascular assessment, perfect intraoperative synergy between neurosurgical and cardiac teams, minimally invasive peripheral vascular access including two femoral vein (21 F) and single arterial (17 F) femoral cannulation, use of total Carmeda coating on BioMedicus pumps in closed circuits, and reduced heparinization without Protamine reversal. All cerebral aneurysms were successfully treated through deep hypothermia (15-18 degrees C) as assessed by intraoperative fluoroscopic controls and Doppler vascular assessment. Mean circulatory support time was 174.2 +/- 29.6 min. Circulatory arrest period was 20 +/- 12 min. All patients survived and were extubated within 48 h. No major deficit was observed clinically or on postoperative CT scan. No hemorrhagic complications occurred (mean transfusions was 2.2 blood units). This work supports an extensive use of heparin-coated surfaces for complex circulatory assist techniques, either for cardiac or extra cardiac complex procedures.

Multiple valve replacement increases the risk of reoperation for structural degeneration of bioprostheses

BACKGROUND AND AIM OF THE STUDY

The study aim was to analyze the results of reoperations for structural degeneration of bioprostheses, and to define a high-risk population for reoperative procedures.

METHODS

A series of 524 consecutive patients who had undergone a first reoperative replacement for a failed bioprosthesis between 1978 and 1998 was reviewed retrospectively. The reoperative procedure comprised 363 single valve replacements, and 161 multiple valve replacements. During the original procedure, 648 bioprostheses had been implanted in the mitral (n = 403), aortic (n = 220) and tricuspid (n = 25) positions.

RESULTS

The mean interval between the original procedure and reoperation was 8.8 +/- 3.3 years. Tissue valve failure was revealed by recurrence of cardiac insufficiency in 70% of cases. The overall early mortality rate was 8%, but early mortality rates for elective single mitral and aortic reoperative valve replacements were only 3.9% and 4%, respectively. Early mortality following reoperation for single and multiple valve replacement was 6.0% and 12.4% respectively (p = 0.02). Other significant multivariable predictors for early mortality were old age (p = 0.003), NYHA functional class (p = 0.007), presence of ascites (p = 0.02) and reoperation performed before 1988 (p = 0.013).

CONCLUSIONS

The risk of reoperation for structural degeneration of bioprostheses is acceptable for elective single reoperative valve replacement as opposed to multiple reoperative valve replacement. This may limit the use of bioprostheses during the original procedure when multiple valve replacement is required.

Rescue revascularization for acute coronary occlusion late after radiotherapy

Because radiation-induced coronary artery stenoses are frequently severe and located proximally, some patients are admitted in emergency. This report describes the case of a 47-year-old woman with radiation-induced stenosis of the left main coronary artery who presented with cardiac arrest during angiography. The patient was successfully treated using circulatory assistance and percutaneous transluminal coronary angioplasty as a bridge to coronary artery bypass grafting.

Study of left ventricular bypass using Wankel type semipulsatile blood pump

The influence of the Wankel type semipulsatile left ventricular assistance on hemodynamics was investigated with a computer simulation and an animal experiment. A simulation circuit was constructed to express the circulatory system. A current source was added to create a semipulsatile blood pump. The left and right ventricles were replaced by variable compliances. Left heart failure was simulated by decreasing the amount of compliance change of the left ventricle. Under the condition of heart failure when semipulsatile assist flow increased, the mean aortic pressure (AoP), tension time index (TTI), and diastolic pressure time index (DPTI) increased, and the cardiac output, pulse pressure (PP), and pulsatility indicator (PI) decreased. In an animal experiment, a Wankel type blood pump was used in a calf. With the increase of the assist flow, AoP curves became less pulsatile, and PP and PI decreased in accordance, which was predicted by the numerical simulation.

Aortic valve or root replacement with cryopreserved homograft for active infectious endocarditis

Active aortic endocarditis is a serious condition that carries a high mortality and morbidity. The aim of this study was to analyse results obtained from 24 patients who underwent aortic valve or root replacement with cryopreserved homograft for aortic endocarditis. Eleven patients had native valve endocarditis, and 13 had prosthetic valve endocarditis. The mean age was 47.7 years: there were seven women and 17 men. Causative organisms were staphylococci (12), streptococci (four), serratia (one), candida (one), pneumococci (one), while no organisms were isolated in the remaining five patients. Complete reconstruction of the aortic annulus with homograft conduits was necessary in 20 patients (six total root and 14 mini-root). Infracoronary homograft aortic valve replacement was performed in the remaining patients. One patient died 1 day after the operation from ventricular failure, and two others died after 4 and 6 months as a result of arrhythmia. One patient died of recurrent endocarditis 1 year after surgery. The actuarial survival rate at 3 years was 83.4%. All survivors are symptom-free, with no evidence of recurrent endocarditis. Doppler echocardiography showed minimal aortic regurgitation in four patients.

Value of Doppler echocardiography in the detection of low-grade rejections after cardiac transplantation

Modifications of the diastolic parameters pressure half-time (PHT) and isovolumic relaxation time (IVRT), recorded using cardiac Doppler echocardiography (CDE), were studied in 23 heart transplant recipients and compared to the results of 345 endomyocardial biopsies (EMB) performed on the same day. Two different protocols, analyzing respectively (1) a decrease of 20% or more in IVRT and/or PHT with respect to the mean and (2) a decrease of 20% or more in IVRT and/ or PHT with respect to its preceding value, were used to evaluate the efficiency of CDE in diagnosing mild and moderate rejections. When a mild rejection was detected by EMB, a statistically significant decrease was found in the average CDE parameter values of the patient population. However, these variations were weak and did not differ from the spontaneous variations observed in each patient in the absence of rejection. Thus, it is not surprising that the sensitivity of CDE in the detection of mild rejections was very low (45%) using the most sensitive protocol (variations of the parameters from their preceding value). We conclude that CDE alone does not seem to be sufficient to perform the noninvasive diagnosis of low-grade rejections and must be complemented by other noninvasive methods.

Cora valveless pulsatile rotary pump: new design and control

For decades, research for developing a totally implantable artificial ventricle has been carried on. For 4 to 5 years, two devices have been investigated clinically. For many years, we have studied a rotary (but not centrifugal) pump that furnishes pulsatile flow without a valve and does not need external venting or a compliance chamber. It is a hypocycloidal pump based on the principle of the Maillard-Wankel rotary compressor. Currently made of titanium, it is activated by an electrical brushless direct-current motor. The motor-pump unit is totally sealed and implantable, without noise or vibration. This pump was implanted as a left ventricular assist device in calves. The midterm experiments showed good hemodynamic function. The hemolysis was low, but serious problems were encountered: blood components collecting on the gear mechanism inside the rotor jammed the pump. We therefore redesigned the pump to seal the gear mechanism. We used a double system to seal the open end of the rotor cavity with components polished to superfine optical quality. In addition, we developed a control system based on the study of the predicted shape of the motor current. The new design is now underway. We hope to start chronic experiments again in a few months. If the problem of sealing the bearing could be solved, the Cora ventricle could be used as permanent totally implantable left ventricular assist device.

Type A dissection of the thoracic aorta: use of MR imaging for long-term follow-up

PURPOSE

To evaluate routine magnetic resonance (MR) imaging for long-term follow-up in patients who undergo surgery for type A aortic dissection.

MATERIALS AND METHODS

Ninety-two MR examinations were performed in 36 patients. Standard spin-echo images were obtained with electrocardiographic gating (n = 92) and rapid images with a fast low-angle shot sequence and intravenous administration of gadopentetate dimeglumine (n = 25). All segments of the native thoracic aorta were evaluated. Anastomoses of the prosthesis and periprosthetic hematoma were carefully analyzed.

RESULTS

Of 22 complications that occurred in 18 patients, 18 were diagnosed at MR imaging (nine false aneurysms and nine aneurysms distal to the graft). Nine patients underwent reoperation. The findings at MR imaging correlated with those at surgery.

CONCLUSION

Routine follow-up with MR imaging should improve long-term survival in patients who survive emergency surgical repair of type A aortic dissection.

Experimental use of a semipulsatile rotary blood pump for cardiopulmonary bypass

We tested our valveless pulsatile rotary blood pump (CORA) extensively in animals, but only as a temporary implantable left ventricular assist device. To expand the scope of future clinical applications, we recently undertook experiments to assess the feasibility of our pump for use in a standard cardiopulmonary bypass circuit. We conducted 4 experiments in adult sheep (body weight, 40 kg): 2 with CORA and 2 with the BioMedicus pump (BP) for comparison. In all experiments, a currently used extracorporeal circuit with reservoir, filter, and membrane oxygenator (Sorin monolith) was installed, and open chest extracorporeal circulation (ECC) was performed for 6 h. Hemodynamic performance and hemolysis were evaluated. CORA provided semipulsatile systemic flow at a level comparable to that of the BP. Free plasma hemoglobin levels were slightly higher with CORA, but the decrease in platelet count was the same for both devices. There was no significant difference in the extent of blood trauma. We conclude that CORA could be successfully used for ECC with an oxygenator. Negative pressure can be prevented by our specially designed control system.

Clinical situations and results of cardiopulmonary support by peripheral access for resuscitation and recovery

Use of cardiopulmonary support (CPS) by peripheral access with a membrane oxygenator has made considerable progress as a result of the development of centrifugal pumps, percutaneous cannulation, and preheparinized circuits. We have used CPS for resuscitation in 3 cases, for recovery after cardiotomy in 6 cases (myocardial insufficiency, 4; pulmonary arterial hypertension, 1; respiratory insufficiency, 1), and after heart transplantation in 1 case. Of these 10 patients, 3 died during CPS, 5 were successfully weaned, and 2 underwent heart transplantation. Use of CPS is expanding for emergency cardiac assistance. Installation is simple and rapid. It allows recovery of organs pending more invasive and costly techniques.

[Repeated heart valve replacements: prognosis and results]

In order to determine the prognosis of reoperation for valvular replacement, we reviewed the results of a consecutive series of 124 patients operated in the department between 1974 and 1992 (163 multi redo operations). There were 69 women and 55 men, with a mean age 48 years; 77% of the patients were in functional class III or IV. Operations were performed as an emergency in 30% of cases. Endocarditis was found in 24% of cases and was an important risk factor in this content. The main indications for reoperation were periprosthetic leakage in 28.8% of cases and failure of bioprostheses in 23.7%. The valvular replacement was simple in 61%, double in 32% and triple in 7% of cases. An associated procedure was necessary in 27% of cases. Mechanical devices were implanted in 62.3% of cases. Peroperative mortality was 3% and hospital mortality, mainly from cardiac causes, was 21.7% for the second, 20% for the third and 55.6% for the fourth reoperations. Operative mortality was dependent on the number or reoperations, functional class, emergency surgery, duration of bypass and cross-clamping time. Four per cent of patients were lost to follow-up and 30 patients died secondarily. The actuarial survival rate was 52% at 5 years and 33% at 10 years, actuarial survival rate without valvular complication was 41% at 5 years and 19% at 10 years but the functional results remained good with over 90% of patients in functional class I or II at the end of follow-up.

Development of the Marseilles pulsatile rotary blood pump for permanent implantable left ventricular assistance

We have developed a low-speed, double-lobed hypocycloidal pump that furnishes a pulsatile flow without valves. The pump is coupled to a specially designed electric motor. The motor/pump unit is totally implantable and has been extensively tested in vitro and in vivo in animals. Because this pump is volumetric, it is necessary to control speed precisely to avoid overpumping. Our control system, which is based on analysis of the motor current wave form, can detect and prevent negative pressures before they occur. The physical properties and hemocompatibility of several construction materials have been studied to determine their suitability for clinical use. These materials include a graphite substrate, titanium nitrate surface coating, boric carbon, and amorphous diamond. The pumps currently being tested are made of titanium, but clinical versions will be made of composite materials selected from this preliminary study. In vivo testing of this pump confirmed its good hemodynamic performance, low hemolysis rate, and biocompatibility (i.e., low heat, noise, and vibration levels). Animal experiments were terminated after 15 days because of mechanical failure related to the accumulation of blood components on moving parts. A new pump in which the mechanism is completely sealed from the blood flow has been designed and will soon be tested. If this sealed design is effective, the pump should be ready for use as a permanent implantable ventricular assistance device.

Right-sided aortic arch: surgical treatment of an aneurysm arising from a Kommerell's diverticulum and extending to the descending thoracic aorta with an aberrant left subclavian artery

The case of a 44-year-old black man who presented with severe dysphagia, cough and chest pain caused by a 12-cm aneurysm developing from a Kommerell's diverticulum at the origin of an aberrant retro-oesophageal left subclavian artery is reported. The aortic arch and descending thoracic aorta were right sided. Diagnosis was established before operation by computed tomography, magnetic resonance imaging and arteriography. The aneurysm extended a considerable distance down the descending aorta and therefore the risk of postoperative paraplegia was considered to be high. Accordingly selective arteriography was performed to locate the Adamkievicz's artery which arose only 2 cm below the end of the aneurysm. Resection grafting of the aneurysm including the upper third of the descending aorta via right thoractomy was performed. The patient made an uneventful recovery and was discharged 20 days later. This case appears to be the first successful operation for this pathology.

Control of a rotary pulsatile cardiac assist pump driven by an electric motor without a pressure sensor to avoid collapse of the pump inlet

Our ventricular assist device uses a valveless volumetric pump operating on the Maillard-Wankel rotary principle. It is driven by an electric motor and provides a semi pulsatile flow. At each cycle, blood is actively aspirated into the device, and overpumping results in collapse at the pump inlet. To prevent overpumping, it is necessary to ensure that pump intake does not exceed venous return. Poor long-term reliability rules out the use of current implantable pressure sensors for this purpose. To resolve this problem, we have developed a method of control based on monitoring of the intensity of electric current consumed by the motor. The method consists of real time monitoring of current intensity at the beginning of each pump cycle. A sudden change in intensity indicates underfilling, and motor speed is reduced to prevent collapse. The current consumed by the motor also depends on the afterload, but the form of the signal remains the same when afterload changes. After demonstrating the feasibility of this technique in a simulator, we are now testing it in animals. We were able to detect and prevent collapse due to overpumping by the cardiac assist device. This system also enables us to know the maximum possible assistance and to thus adapt assistance to the user.