[Severe infective endocarditis through the history]

The history of infective endocarditis (IE) is a good example of medical progress. Initially incurable, endocarditis, when diagnosed, was synonym of death. After significant diagnostic progress, thanks to Osler's contribution especially, the first surgeries and antibacterial drugs obtained very few successful cures. We had to wait until Flamming's discovery to observe frequent cures thanks to antibiotics. Surgery manages to push possibilities of cure a bit further. However, paravalvular extensions, described since the first surgical case of IE, was a real technical matter. Thus, the second half of 20th century was devoted to overcoming this surgical challenge. In this historical review, we describe the story of severe IE, especially with paravalvular involvement, by highlighting major progress - clinical and surgical, that allows its current management.

CT-scan images preprocessing and segmentation to improve bioprosthesis leaflets morphological analysis

The visualization of bioprosthesis leaflet morphology might help to better understand the underlying mechanism of dysfunction in degenerated aortic bioprosthesis. Because today such visualization of bioprosthesis leaflet morphology is intricate to impossible with other imaging techniques, we hypothesized that the processing of multi-detector CT images would allow better visualization of the prosthetic valve leaflets after biological aortic valve replacement. The purpose of our study was to prospectively evaluate patients with a degenerated aortic bioprosthesis, waiting for reoperation, by using 64-slice CT to evaluate prosthetic leaflets morphology. A semi-automatic segmentation of pre-operative tomodensitometric images was conducted, using 2 different implementations of the region growing algorithm. Here we report all segmentation steps (selection of the region of interest, filtering, segmentation). Studied degenerated aortic bioprostheses were represented by two Carpentier-Edwards Supra Annular Valve (porcine leaflets), one Edwards Perimount (pericardial leaflets) and one Medtronic Mosaic (porcine leaflets). Both segmentation methods (Isotropic Region Growing and Stick Region Growing) allowed a semi-automatic segmentation with 3D reconstruction of all bioprosthetic components (stent, leaflets, degeneration/calcifications). Explanted bioprosthesis CT images were also processed and used as reference. Segmentation results were compared by means of quantitative criteria. Semi-automatic segmentation using region growing algorithm seems to provide an interesting approach for the morphological characterization of degenerated aortic bioprostheses. We believe that in the next future CT scan images segmentation may play an important role to better understand the mechanism of dysfunction in failing aortic bioprostheses. Moreover, bioprostheses 3D reconstructions could be integrated into preoperative planning tools to optimize valve-in-valve procedure.

[Heart transplantation for patients on high emergency list with or without extracorporeal membrane oxygenation support]

OBJECTIVE

Severely impaired patients may wait in France on a special and temporary high emergency national list (called SU). Some of these patients need mechanical circulatory support with ECMO. In order to compare two groups of patients on SU, who acceeded to heart transplantation (HT) with or without ECMO, we reviewed retrospectively 20 consecutive patients transplanted on SU between January 2004 and September 2007 in Rennes.

PATIENTS AND METHODS

Among them, 10 were transplanted without ECMO and 10 others were implanted with a femoro-femoral ECMO before HT.

RESULTS

(1) Considering the group SU without pretransplantation ECMO: 2 years survival rate was 70%. Mean hospital stay was 26.4 days. Three patients were implanted with ECMO for graft dysfunction during postoperative course, without inherent complication. None graft dysfunction occurred after initial hospitalization; (2) considering the group SU with pretransplantation ECMO: 2 years survival rate was 90% (one early death). Mean hospital stay was 45 days with multiple complications due to the ECMO (leg's ischemia: n = 2; lung oedema: n = 1; lymphorrhea: n = 3, low flow requiring change of canulae: n = 1). None graft dysfunction occurred after initial hospitalization.

CONCLUSION

Although we didn't reach statistical significance, it seems that ECMO for patients in SU may be useful as bridge to transplant but with a higher morbidity than for similar patients transplanted without ECMO. Additional data from other transplant centers are needed to confirm our findings.

[Pilot study of a strategy combining coronary angioplasty with valvular and/or coronary surgery on the same day]

A strategy combining percutaneous coronary angioplasty followed by valvular and/or coronary surgery was recently proposed as an alternative to the classical surgical only approach. The aim of this study was to assess the feasibility and the results of such a combined strategy with the two procedures performed the same day. The population comprised 34 patients including 17 with valvular disease and revascularisable coronary lesions (15 symptomatic severe aortic stenoses and two acute mitral insufficiencies) plus 17 multitrunk coronary patients without valvular disease but with an indication for revascularisation. Angioplasty was performed several hours prior to surgery and a loading dose of 300mg clopidogrel was administered immediately postoperatively; all patients were on aspirin before the procedure. The average age was 67 +/- 11 years, NYHA class 2.3 +/- 0.7, angina 73%, LVEF 58 +/- 10%. Single coronary artery disease was present in 26%, two vessel disease in 35% and three vessel disease in 39%. The success rate for angioplasty plus stent was 98%. 60 stents were active. Bypasses were exclusively arterial (left or right internal mammary arteries). We observed 4 in-hospital deaths, one of which was due to an infarct and three due to extra-cardiac causes (1 non-cardiogenic acute respiratory distress syndrome, 1 respiratory tract infection and 1 pyelonephritis). Further surgery was necessary in 4 cases: for haemorrhage and one episode of digestive tract haemorrhage. There were no additional deaths, coronary events nor haemorrhage at the end of an average follow-up of 15 +/- 6 months. The results of this combined strategy are encouraging in this population and merit further evaluation in a prospective study.

[Valve replacement for aortic regurgitation associated with rheumatoid arthritis: a series of 5 cases]

Between 30 and 50% of patients with rheumatoid arthritis (RA) have cardiac involvement but only 2 to 10% have clinical manifestations. The authors report the results of a retrospective study of 5 cases of aortic regurgitation (AR) requiring valve replacement. There were 4 women and 1 man with an average age of 48.4 years. The average duration of the RA was 19.6 years. All patients had cardiac failure. Aortic valve replacement was performed in all cases, with bioprostheses in 4 out of 5 patients. The histopathological examination of the valves showed a rheumatoid nodule in 3 cases and non-specific lesions in one case. In the fifth patient, rheumatoid serology was positive in the pericardial effusion. The average interval between the onset of symptoms and cardiac surgery was 3.6 months (range 1 to 6 months) There were 3 deaths at 3 days, 20 months and 10 years, two patients survive after 12 and 14 years. The characteristic rapid progression of this form of AR, which may be life-threatening, should be emphasised.

[Early non-obstructive thrombosis of mechanical mitral valve prostheses]

Transoesophageal echocardiography has shown a high incidence on non-obstructive thrombosis after mitral valve replacement with a mechanical prosthesis. The unpredictable outcome and the period during which the complication arises make treatment difficult. The aim of this study was to assess the tolerance and efficacy of the association of long-term heparin and oral anticoagulation, as recommended in this indication. All patients undergoing mitral valve replacement with a mechanical prosthesis between June 1999 and July 2001 were systematically included and studied by transoesophageal echocardiography in the immediate postoperative period. Those with non-obstructive thrombosis at least 5 mm in size were treated by heparin and oral coagulation until the thrombus disappeared on transoesophageal echocardiography. One hundred and fourteen patients undergoing 120 mitral valve replacements (6 reoperations) underwent transoesophageal echocardiography and non-obstructive thrombi measuring at least 5 mm were found on 26 occasions (21.7%). The association of heparin and oral coagulation was maintained for 7 to 115 days (average 20 days). No thromboembolic or haemorrhagic complications and no deaths were observed during this period. Two patients were treated with danaparoid and oral anticoagulation because of heparin-induced thrombocytopenia before the diagnosis. None of the patients died during follow-up (average 49 months); there were 4 recurrent non-obstructive thromboses, three of which were complicated by thromboembolic events with no sequellae in the first 8 months, again treated effectively with the association of heparin and oral anticoagulants; two cerebral embolic events without sequellae were observed without a demonstrable non-obstructive thrombus on transoesophageal echocardiography. The authors conclude that the association of heparin and oral anticoagulants seems well tolerated and effective in this small population and this would justify a large scale clinical trial.

Valve replacement in patients with critical aortic stenosis and depressed left ventricular function: predictors of operative risk, left ventricular function recovery, and long term outcome

OBJECTIVES

To identify predictors of operative and postoperative mortality and of functional reversibility after aortic valve replacement (AVR) in patients with aortic stenosis (AS) and severe left ventricular (LV) systolic dysfunction.

METHODS AND RESULTS

Between 1990 and 2000, 155 consecutive patients (mean (SD) age 72 (9) years) in New York Heart Association (NYHA) heart failure functional class III or IV (n = 138) and with LV ejection fraction (LVEF) < or = 30% underwent AVR for critical AS (mean (SD) valve area index 0.35 (0.09) cm2/m2). Thirty day mortality was 12%. NYHA class (3.7 (0.6) v 3.2 (0.7), p = 0.004), cardiothoracic ratio (CTR) (0.63 (0.07) v 0.56 (0.06), p < 0.0001), pulmonary artery systolic pressure (63 (25) v 50 (19) mm Hg, p = 0.03), and prevalence of complete left bundle branch block (22% v 8%, p = 0.03) and of renal insufficiency (p = 0.001) were significantly higher in 18 non-survivors than in 137 survivors. In multivariate analysis, the only independent predictor of operative mortality was a CTR > or = 0.6 (odds ratio (OR) 12.2, 95% confidence interval (CI) 5.4 to 27.4, p = 0.002). The difference between preoperative and immediate postoperative LVEF (early-DeltaEF) was > 10 ejection fraction units (EFU) in 55 survivors. In multivariate analysis, CTR (OR 5.95, 95% CI 3.0 to 11.6, p = 0.006) and mean transaortic gradient (OR 1.05, 95% CI 1.0 to 1.1, p < 0.05) were independent predictors of an early-DeltaEF > 10 EFU. During a mean (SD) follow up of 4.6 (3) years, 50 of 137 (36%) 30 day survivors died, 31 of non-cardiac causes. Diabetes (OR 3.8, 95% CI 2.4 to 6.0, p = 0.003), age > or = 75 years (OR 2.6, 95% CI 2.1 to 4.5, p = 0.004), and early-DeltaEF < or = 10 EFU (OR 0.96, 95% CI 0.94 to 0.97, p = 0.01) were independent predictors of long term mortality. Among 127 survivors, the percentage of patients in NYHA functional class III or IV decreased from 89% preoperatively to 3% at one year. The decrease in functional class was significantly greater in patients with an early-DeltaEF > 10 EFU than patients with an early-DeltaEF < or = 10 EFU (p = 0.02). In addition, the mean (SD) LVEF at one year was 53 (11)% in patients with an early-DeltaEF > 10 EFU and 42 (11)% in patients with early-DeltaEF < or = 10 EFU (p < 0.001).

CONCLUSIONS

Despite a relatively high operative mortality, AVR for AS and severely depressed LVEF was beneficial in the majority of patients. Early postoperative recovery of LV function was associated with significantly greater relief of symptoms and longer survival.

[The long term (15 years) evolution after valvular replacement with mechanical prosthesis or bioprosthesis between the age of 60 and 70 years]

OBJECTIVE

the aim of this study was to document the choice between prosthesis and bioprosthesis in cases of valvular replacement during the seventh decade of life.

METHODS

a retrospective and cooperative study linking eleven cardiac surgical teams and five medical cardiology teams combined 497 subjects born between 1915 and 1925 (average age 64.4 years) who underwent aortic (313 cases) or mitral (184 cases) valvular replacement with mechanical prosthesis (259 cases) or bioprosthesis (238 cases). Information was collected at each centre during the year 2000 on the long term evolution (going back 15 years), in particular on the mortality, non-fatal complications linked to the valve, cardiac complications and extra-cardiac events. These results were subjected to statistical analysis.

RESULTS

the operative mortality of this group was 4.8%. The 15 year survival was 46% for the aortic mechanical prostheses, 32% for the aortic bioprostheses (p=0.04). 34% for the mitral bioprostheses and 33% for the mitral mechanical prostheses. Events linked to the valve were more frequent for the mitral valvulopathies than for the aortic valves (49% vs 26%, p<0.001). The absence of events linked to the valve at 15 years was 69% for the aortic mechanical prostheses and 68% for the aortic bioprostheses. This was the case in only 57% of mitral mechanical prostheses and 36% of the mitral bioprostheses (p=0.11). Thromboembolic accidents were three times more frequent in the mitrals than in the aortics (11.5 vs 3.8%, p=0.002). Haemorrhage was four times more frequent for the mechanical prostheses than for the bioprostheses (7.7 vs 2%, p=0.01). The risk of degeneration for the aortic bioprostheses was 20% at 15 years, three times less so after 65 years of age (p=0.03). At 48% it was much higher in the mitral valves at 15 years with no significant difference before and after 65 years of age (p=0.3).

CONCLUSION

the current life expectancy of subjects in their seventh decade is important. The greatly elevated risk of bioprosthesis degeneration in the mitral position does not allow this alternative to be advocated before 70 years of age. In the aortic position, this risk is elevated before 65 years of age. It is lower after 65 years old. Nevertheless, this means the risk of reoperation in certain octogenarians must be accepted, balanced with the linear risk of haemorrhagic accidents for which a future reduction is expected thanks to milder anticoagulation for aortic mechanical prostheses and anticoagulation autocontrol.

[Return to work after cardiac valvular surgery. Retrospective study of a series of 105 patients]

This was a retrospective study realised by a mailed questionnaire of the medical and socio-professional conditions of return to work in patients with valvular heart disease aged 20 to 59 and operated in the cardiac surgery department of Rennes University Hospital in 1998. The results concern 105 patients of whom 78 were working before surgery and 27 were unemployed, and 53 were professionally active after surgery. The average age was 48 +/- 9 years and the male/female ratio was 2.38. After surgery, 78.4% of patients were NYHA Stages I or II, compared with 38.1% before surgery. Three main surgical procedures were carried out, sometimes in association: aortic valve replacement (71.4%), mitral valve replacement (21%) and mitral valvuloplasty (11.4%). Valve replacement was with a mechanical prosthesis in 83% of cases, a bioprosthesis in 11% of cases and a homograft in 6% of cases. Return to work (67.9%) after an average of 5.3 +/- 3.9 months was correlated with the following factors: age: 50 years old patients or more, were less likely to return to work (p < 0.02); postoperative NYHA stage: patients in stages III and IV were less likely to return to work (p < 0.03); the time off work before surgery: the longer the time (threshold > 6 months) the less likely the patients are to return to work (p < 0.03). Return to work was preferred to non-return (p < 0.03). This study shows the difficulties of professional rehabilitation of patients despite a satisfactory general condition. This is partially explained by the difficult economic context which favorises invalidity but also by the lack of information concerning the role of works doctors in the return to work. The realisation of a liaison file with permission of the person concerned between the general practitioner, the cardiologist and a medico-social security doctor and works doctor should remedy the difficulties in communication and sustain a policy of return to work.

Isolated left main coronary artery stenosis: long term follow up in 106 patients after surgery

OBJECTIVE

To analyse the long term prognosis in patients with isolated stenoses of the left main coronary artery (LMCA) following surgical revascularisation.

PATIENTS

106 patients (71 men and 35 women, mean age 61 years) were operated on between 1982 and 1998. Before surgery, 103 patients presented with angina pectoris and only 10 had a history of myocardial infarction. Their mean left ventricular ejection fraction was 62%. Stenoses were localised on the LMCA ostium in 19 patients, a subgroup characterised by a high proportion of women (68%). Three patients presented with chronic LMCA occlusion. Forty six patients were operated on as an emergency. The mean (SD) number of grafts per patient was 2.0 (0.5), and only one patient had no left anterior descending (LAD) coronary artery bypass. Bypass of the LAD using the internal thoracic artery was performed in 88 cases.

RESULTS

Early postoperative mortality was 4.7% and the five year survival was 86.8%. Late mortality occurred in nine cases, and in three of these it was linked to a coronary condition. Of the 92 long term survivors, 81.5% were totally symptom-free and 77% of those of working age were able to resume work. The postoperative outcome of patients with isolated ostial LMCA stenosis did not differ significantly from that of the other patients.

CONCLUSIONS

The postoperative prognosis of isolated LMCA stenosis appears good in terms of mortality and symptoms.

[Results of surgical treatment of calcified aortic valve stenosis: report of a series of 4,129 interventions]

Aortic stenosis (AS) is the most common lesion currently encountered among valvular heart disease, particularly in elderly people. Severe functional impairment and risk of sudden death explain that surgical treatment is largely accepted. We report a retrospective analysis of institutional experience with aortic valve replacement (AVR) for AS from 1971-1997 in 4,129 patients. Age ranged from 13 to 91 years (mean 68 +/- 10) and degenerative disease was largely predominant (86%). For AVR, mechanical prostheses were used in 2,054 patients (50.2%) and bioprostheses in 2,075 (48.8%) in elderly group. Coronary artery revascularization was associated in 670 patients (16%). Operative mortality was 7% (303 pts) and main cause was left ventricular failure (52%). Late results were studied with a maximum follow-up of 26 years. Total follow-up represents 21,533 pt-years. Late death occurred in 1,108 patients between 1 month and 24 years after operation (mean 6.6 years). Reoperation was necessary in 136 cases. Actuarial survival--including operative mortality--was 77% and 56% at 5 and 10 years. A large functional improvement was observed in the vast majority of patients, 73% being I or II subgroups of the NYHA classification. Incremental risk factors for death (immediate as well as late) were older age, preoperative functional status, emergency, presence of cardiac failure, coronary artery lesions and associated morbidity. The choice of valvular prosthesis remains controversial, but the results show that AVR is the procedure of choice for the vast majority of patients wtih significant aortic valve disease.

Feasibility of the utilisation of the right internal thoracic artery in the transverse sinus in off pump coronary revascularisation: early angiographic results

OBJECTIVE

The objective of this study was to analyze the feasibility of beating heart coronary surgery and to angiographically assess complete revascularisations with routine use of the two internal thoracic arteries (ITA), with the right ITA pedicled and placed through the transverse sinus. The authors report the results of their initial experience of coronary surgery without CPB, which began in December 1998.

METHODS

From December 1998 to October 1999, 50 patients underwent non-urgent beating heart coronary revascularisation via a median sternotomy with the 2 ITA. Stabilization of the anastomotic site was ensured by the Octopus stabilizer 1 then 2. A troponin Ic assay was systematically performed in the initial postoperative period. With the patient's consent, postoperative angiography was performed before discharge.

RESULTS

The mean number of anastomoses was 2.5+/-0.6 per patient (range: 2-4). Distal anastomoses by arterial grafts were performed in 87% of cases. In one case, the right ITA could not be kept pedicled and tunnelled in the transverse sinus and a Y graft onto the left ITA had to be performed. Left anterior descending-diagonal sequential bypass with the left ITA was performed in seven patients (14%). There was no operative mortality. One patient developed postoperative myocardial infarction. Follow-up angiography was performed in 42 cases (84%), with 104 anastomoses reviewed (85%). The patency rate for all anastomoses was 98.1%, with 90.4% of excellent results. The patency rate of the right ITA was 100%, with 90.5% of excellent results.

CONCLUSIONS

Beating heart coronary surgery allows revascularisation of all coronary territories. This technique is not an obstacle to the use of the pedicled right ITA tunnelled in the transverse sinus. It is not associated with an increased postoperative morbidity and mortality, and the early follow-up angiographic results are excellent.

Structural durability in Carpentier Edwards Standard bioprosthesis in the mitral position: a 20-year experience

BACKGROUND AND AIM OF THE STUDY

Few long-term data are available on the Carpentier-Edwards Standard bioprosthesis in the mitral position. As for other bioprostheses, patient age at the time of implant is the main risk factor for structural deterioration, but no published report has analyzed the life-span of these bioprostheses with respect to this parameter.

METHODS

A series of 139 patients who underwent mitral valve replacement with the Carpentier-Edwards Standard bioprosthesis between 1978 and 1987 was reviewed. Mean age at implant was 59.6+/-14.7 years (range: 17-79 years). Follow up was 98.4% complete; total follow up was 1,078.7 patient-years (pt-yr) (mean 8.4+/-4.1 years). Mean follow up in the subgroup of patients alive at the time of the survey was 10.4+/-3.4 years.

RESULTS

Structural valve deterioration (SVD) occurred in 30 patients, with mean time to onset of deterioration 9.0+/-2.7 years (median 8.7 years). This time was independent of age at the time of implantation. Analysis by age group (< or =35, 36-50, 51-60, 61-65, 66-70, >70 years) showed deterioration to be more frequent in younger subjects (linear rates 7.9, 6.0, 3.3, 2.4, 0.6 and 0.4% pt-yr, respectively). Over the age of 65 years, the risk of SVD no longer varied with age, and was a rare complication.

CONCLUSION

The mean time to onset of SVD was independent of patient age at the time of implant. After 65 years, the risk of SVD was low, without any significant variation. The Carpentier-Edwards Standard bioprosthesis may be used in the mitral position in subjects aged over 65 years, and with a low risk of deterioration.

Carpentier-Edwards supraannular porcine bioprosthesis in aortic position: 16-year experience

BACKGROUND

The aim of the study was to evaluate the long-term results of aortic valve replacement with the Carpentier-Edwards supraannular porcine bioprosthesis.

METHODS

A total of 278 patients who underwent aortic valve replacement between January 1983 and December 1986 were reviewed. Mean age was 69.4+/-11.0 years (range 24 to 90 years).

RESULTS

The operative mortality was 8.6% (24 patients). The total follow-up was 2367.1 years (mean 9.3+/-4.3 years, maximum 15.5). The late mortality rate was 6.8%/patient-year (162 patients) and the overall survival at 15 years was 26.5%+/-3.6%. Structural valve deterioration (SVD) occurred in 19 patients (linearized rate 0.8%/ patient-year). The mean time to onset of deterioration was 10.9+/-2.9 years. This time was independent of the age at the time of implantation. The freedom from SVD at 10, 12, and 15 years for patients aged less than 60 was respectively 87.6%+/-6.8%, 77.8%+/-8.9%, and 44.2%+/-12.9% (linearized rate 3.3%/patient-year). For patients aged 61 to 70 years, freedom from SVD was, respectively, 100%, 97.3%+/-2.1%, and 80.8%+/-8.3% (linearized rate 0.63% patient-year). For patients older than 70 years, it was respectively 99.1%+/-0.9%, 95.6%+/-2.6%, and 93.3%+/-3.3% (linearized rate 0.31%/patient-year). No significant difference was observed below the age of 60 years (< or =50 vs 51 to 60 years) or in the older subgroups (61 to 70 years, vs >70 years).

CONCLUSIONS

The Carpentier-Edwards supraannular bioprosthesis in aortic position provides low rate of structural valve deterioration at 15 years in patients aged more than 60 years at the time of implantation. The mean time to onset of SVD is independent of the subject's age at the time of implantation. After 60 years, the risk of deterioration is low and does not present any significant variation. The Carpentier-Edwards supraannular bioprosthesis can reliably be used for aortic valve replacement in patients over the age of 60 years because, beyond this age, SVD is observed much more rarely.

Echocardiographic assessment and preliminary clinical results after aortic valve replacement with the Medtronic Mosaic bioprosthesis

BACKGROUND AND AIM OF THE STUDY

The study aim was to examine prospectively the clinical performance and durability of the Medtronic Mosaic bioprosthesis, a stented porcine aortic valve that combines improvements in tissue preservation, notably net zero differential pressure fixation of the leaflets, with antimineralization treatment using 2-amino-oleic acid (AOA).

METHODS

A total of 158 Mosaic valves was implanted; 152 in patients aged over 70 years, and six in patients aged <70 years with contraindications to anticoagulant therapy. Mean age was 73.7 years. All valves were implanted in the supraannular position. Thirty-two patients (20%) required concomitant procedures, including coronary revascularization, ascending aorta replacement and/or mitral annuloplasty. Postoperative anticoagulation (heparin) was prescribed for ten days, followed by antiplatelet therapy. No long-term oral anticoagulants were prescribed, except in some patients with atrial fibrillation. The follow up included routine clinical and blood work-up, and echocardiography at six months and one year after surgery.

RESULTS

There were seven early (0-30 days) and five late deaths (>30 days). One death was caused by a hemorrhagic stroke at three months in a patient without anticoagulant or antiplatelet therapy. No thromboembolic complications or structural valve deterioration were observed during follow up. At two years, freedom from endocarditis and reoperation was each 99.6%. NYHA class was excellent, with 98% of patients in class I or II at one year. Patient survival was 92% at two years. Hemodynamically, the valve was performing well, with mean systolic gradients of 13.6, 13.2, 12.6 and 9.6 mmHg for the 21, 23, 25 and 27 mm valves, respectively. There was no evidence of structural valve deterioration.

CONCLUSION

Long-term evaluations are mandatory to confirm the durability of any new bioprosthetic valve. Satisfactory early clinical and hemodynamic results with the new Mosaic bioprosthesis warrant its continued implantation in the aortic position for patients over the age of 70 years.

Prospective evaluation of coronary arteries: influence on operative risk in coronary artery surgery

OBJECTIVE

Coronary angiography data included in the analysis of operative mortality after coronary artery surgery are generally limited to left main coronary artery stenosis and classification into one-, two- or three-vessel disease, but the role of stenoses and quality of distal runoff on each main coronary artery have never been analysed. The aim of this study was to assess the influence of coronary artery status (stenoses and distal runoff) on operative mortality in patients undergoing coronary artery surgery.

METHODS

Stenoses of the five main coronary arteries and their distal runoff were prospectively evaluated in a series of 2461 patients undergoing isolated coronary artery surgery. These angiographic variables were included in analysis of operative mortality in combination with conventional preoperative data.

RESULTS

Univariate analysis founded 21 preoperative variables being significant: age >70, body surface area <1.8 m2, arterial disease of lower limbs, history of peptic ulcer, CCS class IV angina, unstable angina, post-infarction unstable angina, congestive heart failure, left ventricular ejection fraction <50%, urgency, preoperative intra-aortic balloon pump, previous myocardial infarction, previous cardiac surgery, previous coronary bypass graft, presence of significant stenosis on the left main coronary artery or the circumflex marginal branch or the distal circumflex artery or the right coronary artery, absence of significant stenosis on the left anterior descending artery, impaired distal runoff on the left anterior descending artery or the circumflex marginal branch (for all, P < 0.05). Multivariate analysis identified poor quality distal runoff in the left anterior descending artery and circumflex marginal branch as independent risk factor (P = 0.0005 and P = 0.04, respectively), while left main coronary artery stenosis was not. This lesion appears to be a significant risk factor only in a small subgroup of patients with CCS class IV angina. Other independent risk factors were CCS class IV angina, previous cardiac surgery, body surface area <1.8 m2, diabetes mellitus, age <70, history of peptic ulcer, left ventricular ejection fraction <50%. Impaired distal runoff or the presence of stenoses on the diagonal branch, right coronary artery, or distal circumflex artery does not significantly influence the operative mortality rate.

CONCLUSIONS

The quality of distal runoff of the most frequently grafted vessels is a significant risk factor for operative mortality in coronary artery surgery. Left main coronary artery stenosis was not identified as a risk factor when these angiographic variables were included in the analysis. Functional status remains the most powerful predictive factor.

[Long-term results of valve replacement using the Cobomedics prosthesis]

The Carbomedics valve prosthesis is a second generation mechanical prosthesis with a double hemi-disc. This study analysed long-term morbidity and mortality associated with this prosthesis. Between 1987 and 1996, 397 prostheses were implanted, 306 aortic, 42 mitral and 26 double replacements (3 combining a Carbomedics aortic prothesis with a mitral valve from another type) in 370 patients with a mean age of 62 (range 4 to 88 years). The global operative mortality was 7.4%. A questionnaire sent to treating cardiologists, general practitioners and patients updated the prospective data base of the cardiac surgical department. The follow-up was 99%, representing a total of 1244 patient-years with an average of 41 months (range 1.1 month to 9.9 years). The 1, 3, 5 and 7 year survival (operative mortality included) was 88%, 80%, 76% and 69.6% respectively. Haemorrhagic complications were the most common (17 cases, 1.36% per patient-year) and 11 thromboembolic episodes were observed (0.88% per patient-year) with a higher incidence (p < 10-4) in mitral valve replacement (3.8% in patient-year). The other complications observed were: 5 aseptic paravalvular leaks (0.4% per patient-year) and 5 prosthetic valve infections; no structural alterations were observed. In all, ten reoperations (0.8% per patient-year) were required for prosthetic valve complications. This study shows the reliability of Carbomedics valve prostheses with a low complication rate comparable to that of other modern mechanical valve prostheses.

Aortic Carpentier-Edwards supraannular porcine bioprosthesis: a 12-year experience

BACKGROUND

After 35 years of cardiac valve replacement, the ideal substitute remains to be found. Homografts are considered best but, due to their scarcity, cannot meet the need of valve replacement. Artificial valves (mechanical or biological) remain the most commonly used but controversy is still present as to the better choice. We tested the Carpentier-Edwards bioprosthesis for its efficacy in valve replacement operations.

METHODS

From 1983 to 1995, 1,108 consecutive patients had an isolated aortic valve replacement with a porcine Carpentier-Edwards bioprosthesis, model 2650 supraannular valve. Mean age was 73.8+/-8.3 years. Aortic stenosis was the most common lesion (1,049 patients, 94.7%). The follow-up of 980 operative survivors was 96% complete and represented a total of 4,735 patient-years (maximum, 13.8 years; mean, 4 years and 10 months).

RESULTS

Actuarial survival including operative mortality (128 patients, 11.6%) was 43.6%+/-2.3% at 10 years and 27.3%+/-3.3% at 12 years and, at that time, was not statistically different from those of the normal French population matched for age and sex. Structural deterioration of the valve was observed in 27 patients, an actuarial freedom of 94.2%+/-1.5% at 10 years and 83.8%+/-4.5% at 12 years. Hazard function revealed a stable and low risk of structural deterioration until 10 years and significantly increased risk after that. Young age was found to be an increasing risk factor of deterioration. Reoperation for valve-related complications was necessary in 30 patients, an actuarial freedom of 94.5%+/-1.4% at 10 years.

CONCLUSIONS

The Carpentier-Edwards porcine supraannular valve affords a good durability up to 10 years, with a low rate of reoperation. The risk of structural deterioration decreases with older age. It is our valve of choice in elderly patients.

Aortic valve replacement in the elderly: bioprosthesis or mechanical valve?

BACKGROUND

With increased life expectancy, valve operations are more and more common in elderly patients. The choice of valve substitute-mechanical valve or bioprosthesis-remains debated.

METHODS

Two groups of patients of the same age (69, 70, and 71 years) with isolated aortic valve replacement (mechanical 240, bioprostheses 289) were compared for mortality, morbidity, and valve-related complications.

RESULTS

No significant difference was found in survival, valve-related mortality, valve endocarditis, and thromboembolism. Mechanical valve had more bleeding events; bioprostheses had more structural deterioration, reoperation, and valve-related morbidity and mortality.

CONCLUSIONS

To avoid reoperations in octogenarians, the 10-year durability of current bioprostheses should be matched with the life expectancy of the particular patient. Bioprostheses should be used after 74 years in men and 78 years in women.

Gastric mucosal oxygen delivery decreases during cardiopulmonary bypass despite constant systemic oxygen delivery

Previous studies report a decrease in gastric mucosal oxygen delivery during cardiopulmonary bypass (CPB). However, in these studies, CPB was associated with a reduction in systemic oxygen delivery (DO2). Conceivably, this decrease in DO2 could have contributed to the observed decrease in gastric mucosal oxygen delivery. Thus, in the present study, we assessed the effects of the maintenance of DO2 (at pre-CPB values) during hypothermic (30-32 degrees C) CPB on the gastric mucosal red blood cell flux (GMRBC flux) using laser Doppler flowmetry. In 11 patients requiring cardiac surgery, the pump flow rate during CPB was initially set at 2.4 L x min(-1) x m(-2) and was adjusted to maintain DO2 at pre-CPB values (flow 2.5-2.7 L x min[-1] x m[-2]). Despite a constant DO2, the GMRBC flux was decreased during CPB. These decreases averaged 50% +/- 16% after 10 min, 50% +/- 18% after 20 min, 49% +/- 21% after 30 min, and 49% +/- 19% after 40 min of CPB. The rewarming period was associated with an increase in GMRBC flux. Thus, maintaining systemic DO2 during CPB seems to be an ineffective strategy to improve gastric mucosal oxygen delivery.

IMPLICATIONS

In the present study, we tested the hypothesis that gastric mucosal red blood cell flux assessed by laser Doppler flowmetry could be improved by maintaining baseline systemic flow and oxygen delivery during hypothermic cardiopulmonary bypass. Despite this strategy, gastric mucosal red blood cell flux decreased by 50% during hypothermic cardiopulmonary bypass.

[The Carpentier-Edwards porcine valve in the supra annular aortic position. Results after 12 years in a series of 1108 patients]

In the decision concerning the choice of valvular prosthesis, certain prostheses are considered to be standards of reference: this is the case of the Carpentier-Edwards Supra Annular 2650 porcine bioprosthesis. This study reports the results in a series of patients followed up for 12 years. Between 1983 and 1995, 1108 patients were implanted with this prosthesis for isolated aortic valve replacement. The majority of patients was elderly (mean 78.3 +/- 8.3 years). The follow-up rate was 94%, representing a total of 3 925 patient-years (average 4 +/- 3 years). The survival at 5, 10 and 12 years, operative mortality included, was 70.7%, 46% and 28%. Thromboembolic events to dehiscence represented the commonest complication (0.7% per patient-year). Structural valve degeneration (21 cases) (0.5% per patient-year) was a low risk complication up to 10 years but increased suddenly at the 11th year: age and gender were risk factors for this complication. The actuarial complication-free rate was 94% at 10 years and 82% at 12 years. Other complications were much less common (infectious endocarditis, haemorrage). The Carpentier-Edwards Supra Annular porcine bioprosthesis is associated with a low risk of complications after 10 years' follow-up, especially of valve degeneration. It remains a competitive choice in the register of valve prostheses. As with the other bioprostheses, the main indications are observed in elderly patients.

[Long-term results over 20 years of aortic valve replacement with the standard Björk-Shiley prosthesis]

Between January 1971 and December 1978, 865 standard Björk-Shiley prostheses (spheric or conic carbon disc) were implanted in the Department of Thoracic and Cardiovascular Surgery of the University Hospital of Rennes. Three hundred and fifty seven consecutive patients who underwent isolated aortic valve replacement were included in the study : 246 men (69%) and 111 women (31%) with an average age of 57.5 years (range : 24-80 years). One hundred and sixty eight patients (48%) were in NYHA Class II. 141 (39%) in Class III and 48 (13%) in Class IV. The valvular disease was stenotic in 304 cases (85%) and regurgitant in 53 cases (15%). The hospital mortality was 35 (9.8%). The main causes of death were cardiac (23 cases, 66%). The long-term results contain 322 survivors of surgery (mean follow-up 12 years, follow-up rate 99%, representing 3726 patient-years). The actuarial survival (including hospital mortality) was 76% at 5 years. 61% at 10 years, 47% at 15 years and 26% at 20 years. The average age of the survivors at present is 71 years and 95% are NYHA classes I or II. The causes of the 171 late fatalities were cardiac in 49 cases (1.3% per patient-year). Death was related to the prosthesis in 32 cases (0.8% per patient-year) : 3 endocarditis, 17 bleeding complications, 12 systemic emboli. Deaths were extracardiac in 58 cases (1.5% per patient-year). Prosthesis-related complications were : 9 paravalvular leaks (0.2% per patient-year), 3 dysfunctions (0.1% per patient-year). 24 haemorrhages (0.6% per patient-year), 5 thromboembolic episodes (0.1% per patient-year). 5 endocarditis (0.1% per patient-year). No structural abnormalities of the prostheses were observed. The authors confirm the reliability of the standard Björk-Shiley valve prosthesis in the aortic position and the value of the aortic valve replacement by a mechanical prosthesis even at very long term.

[Mediastinitis after cardiac surgery. A 10-year evaluation (1985-1995)]

From June 1985 to May 1995, 9,814 patients were operated for a cardiac procedure with cardiopulmonary by-pass. Mean age was 61,3 years. The most frequent procedure was coronary surgery (45%), followed by valvular surgery (34%) then combined surgery (11%) and other surgery (4%). 66 cases of mediastinitis were observed: 38 from June 1985 to May 1990 (first group), 28 from June 1990 to May 1995 (second group). The changes between the two groups was antibiotic prophylaxis using Cefuroxime in the first group and Cefamandole in the second and also an impairment of general status of the patients in the second group. Staphylococcus remains the most frequent organism in both groups and for Gram negative bacteria was less frequent in the second group. Several risks factors mediastinitis were identified (males, emergency, diabetes mellitus, obesity, redo, patient of first group, duration of Cardiopulmonary by pass for 100 minutes, mechanical ventilation greater than 48 hours) and the most important factor was the need for mechanical ventilation for more than 48 hours. The mortality rate was 39.4% (26 patients). Identified risk factors of mortality were age over 65 years, females, poor constitution, and cardio/thoracic ratio > 0.55.

CONCLUSION

Mediastinitis after cardiac surgery remains a serious complication. In this series we observed a decrease of mediastinitis rates, especially in the second group (p < 0.001). In high risk patients, specific preoperative methods of patient care may be able to prevent such complications. When mediastinitis appears, and when debridement is necessary, a cover procedure seems necessary in elderly or poor constitution patients.

[Coronary artery disease in patients with aortic abdominal aneurysm. Apropos of a consecutive series of 172 cases]

Coronary artery disease is common in patients with abdominal aortic aneurysms (AAA). It is responsible for half the operative deaths explaining the necessity of diagnosing asymptomatic coronary patients. Between 1980 and 1993, 172 patients aged 47 to 92 years (average 69 years) were operated for AAA. Fifty-four of them (31%) were known to have coronary artery disease; 30 preoperative coronary angiograms and 16 prophylactic coronary revascularisation procedures were performed before operating the AAA. In cases with ruptured AAA (42 cases) the operative mortality was 31% (13 patients) compared with 6% (8 patients) in those without rupture (130 cases). Myocardial disease was responsible for 25% of all deaths (2 out of 8) and for 40% of deaths (2 out of 5) in the subgroup of 54 coronary patients. The majority of non-lethal cardiac complications also occurred in this subgroup. On the other hand, no deaths were observed in the group of 16 patients who underwent myocardial revascularisation beforehand. Follow-up of the 151 patients discharged from hospital was complete (100%). With an average follow-up period of 3.5 years (range 5 months to 13 years), 39 secondary deaths have been observed (26%) including 6 (15%) of cardiac causes. In addition, 3 patients in the coronary subgroup and 1 patient from the non-coronary group underwent myocardial revascularisation after surgical cure of their AAA. Coronary artery disease may be totally asymptomatic and severe lesions go unrecognised; the main problem is therefore to detect silent myocardial ischaemia in the absence of totally reliable non-invasive techniques, in order to perform preventive coronary revascularisation in high risk patients before their surgery. Coronary angiography is essential in all documented cases of severe coronary artery disease; exercise testing and thallium scintigraphy should be proposed in cases with clinical or electrocardiographic presumption of angina. However, systematic investigation is not required in the absence of suggestive symptoms.

[Cardiac transplantation: clinical results. Apropos of 150 cases]

This retrospective study reports the clinical results obtained in a series of 150 heart transplantations performed from October 1986 to January 1995. Overall actuarial survival rate, including operative mortality, was 71% and 57% at 1 and 5 years respectively. Despite a certain level of morbidity, the spectacular functional results in this series are emphasized.

[Postoperative autotransfusion and transfusion evaluation in cardiac surgery]

In cardiac surgery, blood retransfusion from the thoracic drainages, though already ancient, still remains controversial either for its quantitative or its qualitative interests. A retrospective study has been conducted, between the 1st january 1992 and the 30th june 1993, over 1.655 consecutive operations. Most of the patients suffered from coronary disease (937) or a valvular disease (605), others had been operated for a combined valvular and coronary revascularization surgery (113). The safety of this technique, guaranteed by strict rules, allowed a "transfusional strategy" which tends to reduce the homologous blood consumption. Twenty-nine percent of all the patients received homologous red cells units and only 23% of the patients operated for a coronary revascularization. This strategy aims to reduce both the risks of blood transfusion and the health cost.

Aortic valve replacement for aortic stenosis in 200 consecutive octogenarians

From 1978 to 1992, 200 consecutive patients aged between 80 and 90 years had aortic valve replacement for calcified aortic stenosis. Valve replacement was isolated in 187 cases (93.5%), and it was in combination with coronary bypass (n = 12; 6%), mitral valve replacement (n = 1; 0.5%) or surgery of the ascending aorta (n = 4; 2%). These 200 octogenarians represented 7.4% of the 2716 patients operated for aortic stenosis during the study period. One hundred and forty-eight of them (74%) were in NYHA class III or IV. Operative mortality was 11.5% (23 deaths) and the mean duration of hospitalization was 12.7 +/- 4.83 days. After discharge, all 177 surviving patients were followed up for a mean period of 2.8 +/- 2.1 years (range one month to 10.6 years). There have been 49 deaths during the follow up. At the end of the follow up, 127 of the 128 survivors (98.6) were in NYHA classes I or II. Actuarial survival at one, three and five years was 81.7%, 74.8% and 57.14% respectively, which is equivalent to the life expectancy for subjects of the same age without aortic stenosis. It is suggested that despite the increased, yet acceptable, operative risk, valve replacement in octogenarians is justified due to its beneficial effect on life expectancy and quality of life.

[Immediate and long-term results of replacement of the ascending aorta in aneurysm or dissection]

Between April 1974 and November 1992, 181 patients were operated for aneurysm (106) or dissection (75) of the ascending aorta. Eighty patients had replacement with a valvular conduit with reimplantation of the coronary arteries (Bentall procedure), 48 had aortic valve replacement with replacement of the supra-coronary ascending aorta and 53 underwent isolated replacement of the ascending aorta. Twenty-nine patients (16%) died in the postoperative period, mainly of myocardial or neurological complications. Univariate statistical analysis completed by logistic regression analysis revealed the following predictive factors of early death: NYHA Stage IV, angina, reoperation for haemorrhage or tamponade (all < 0.05). All surviving patients were followed up (total follow-up: 788 years; mean: 62 months; range: 1 to 181 months). There were 20 secondary deaths, 40% of which were related to complications of aortic valve replacement. The 5 and 9 year survivals were 76 and 70% respectively, perioperative mortality included, and 89% of patients were in NYHA functional Stage I. Analysis of survival data did not reveal any predictive factor of secondary death. Eight patients were reoperated at long-term. The operative mortality of replacement of the ascending aorta remains high, especially in cases of dissection. The long-term results seem excellent with a low reoperation rate. Late mortality seems mainly due to complications of aortic valve replacement.

[Changes in operative risk and its predictive factors in coronary surgery]

The operative risk of coronary bypass surgery has been reported by many surgical groups. Although the 1970's were characterised by a progressive decline in this risk related to improved surgical techniques and myocardial protection, the following decade saw a new rise in operative mortality. In order to assess this problem, the authors undertook a review of 3,632 consecutive cases of coronary bypass surgery (without any other procedure) from 1982 to 1991. The operative risk increased from 2% in 1982 to 7.7% in 1989 and was related to an increase in patients' age, in left ventricular dysfunction and in the number of emergency and redux operation. The development of interventricular cardiology in the last few years (angioplasty for double or triple vessel disease, thrombolysis in the acute phase of myocardial infarction) has also increased the number of patients operated as emergencies with a high operative risk. The reduction of the operative risk observed since 1989 is due to better overall management (pre, per and postoperative), especially of the high risk patients (patients over 70 years of age, women, left ventricular dysfunction, left main coronary stenosis, emergencies, reoperation). Although many variables indicating extramortality were found to be statistically significant (p < 0.05) on univariate analysis, multivariate analysis by two year periods showed the following independent prognostic factors of operative mortality: persistence of the concept of "emergency surgery" throughout the period under study and, from 1986, the appearance of gender and NYHA Class; and, from 1988, the factor "reoperation" with different values of "p" according to the years under consideration.

[Cardiac tuberculoma; value of echocardiography and therapeutic management apropos of a case]

The authors report the case of a patient with a large mass in the right ventricle which was a tuberculoma without pulmonary disease. The severity of the right ventricular obstruction required surgical intervention with quadri-antitubercular therapy. Myocardial tuberculomas are very rare and usually reported as post-mortem findings. Only four cases resulting in cure have been previously reported. Current means of investigation such as echocardiography and endomyocardial biopsy allow rapid diagnosis of these tumours and should lead to better medical management with possible surgical intervention and a higher therapeutic success rate.

[Valvular replacement for aortic stenosis in octogenarians. Apropos of a consecutive series of 200 cases]

From 1978 to 1992, 200 patients aged 80 to 90 (average 82.16 +/- 2.04 years) with calcific aortic stenosis, underwent isolated aortic valve replacement (187 cases, 93.5%), or associated with coronary bypass surgery (12 cases, 6%), or mitral valve replacement (MVR) (1 case, 0.5%), or surgery of the ascending aorta (4 cases, 2%). These 200 patients represented 7.4% of the 2,716 cases of aortic stenosis operated during the same period. One hundred and forty-eight patients (74%) were in NYHA classes III or IV. The operative mortality was 11.5% (23 patients) and the average hospital stay in the surgical department was 12.7 days (4.83%). The follow-up of the 177 patients who were discharged from hospital was complete (100%) with an average of 2.8 years +/- 2.1 (1 month to 10.6 years). Forty-nine secondary fatalities were observed (28%). Of the 128 survivors at the end of the study, 127 (98.6%) were in the NYHA classes I or II. The actuarial 1, 3 and 5 year survivals were 81.7, 74.8 and 57.1%, respectively. The survival curve of the operated patients was identical to subjects of the same age without aortic stenosis. Despite the high but acceptable operative risk due to the age, valvular replacement surgery is justified by the double benefit of increased longivity and improved quality of life.

Surgery for aortic stenosis in elderly patients. A study of surgical risk and predictive factors

BACKGROUND

Aortic stenosis is the most common valvular lesion occurring among elderly patients and has become extremely frequent because of changing demographics in industrialized countries. Surgical risk after the age of 70 has increased. The increasing older age of patients having surgery justifies an analysis of mortality predictive factors.

METHODS AND RESULTS

Between 1976 and February 1993, we performed 2871 operations for aortic stenosis. This study concerns 675 patients (278 men and 397 women) who were > or = 75 years old. Mean age was 78.5 +/- 3 years. Associated lesions were found in 226 patients. A bioprosthesis was implanted in 632 patients (93.6%). Concomitant surgical procedures were performed in 133 patients. Surgical mortality was 12.4% (84 deaths). A longitudinal analysis has been carried out over four successive time periods to evaluate population evolution during these 17 years. Statistical analysis was performed on 46 variables. Multivariate analysis found age (P < .0001), left ventricular failure (P < .0001), lack of sinus rhythm (P < .01), and emergency status (P < .02) to be presurgical independent predictive factors of mortality.

CONCLUSIONS

Risk-reducing strategy should both favor relatively early surgery to avoid cardiac failure and emergency situations and pay careful attention to the use of myocardial protection and cardiopulmonary bypass. Indications for surgery should remain broad since analysis failed to determine specific high-risk groups to be eliminated, and surgery remains the only treatment for aortic stenosis.