[Interest of evaluation of teaching in thoracic and cardiovascular surgery]

The aim of this work is to reflect on different teaching methods can be used in a surgical teaching and its assessment methods. TWO sessions of Multiple Choice Questions (MCQ) have been proposed, the first before all education, the second after education in order to assess its impact on knowledge. Script Concordance Test (SCT) will replace the traditional interactive case report. Eighteen participants (Group 1) completed both sessions of MCQ: 9 residents (R), 2 equivalent resident (ER), 4 Clinical Fellow (CF), 1 Professor (Pr) and 2 senior surgeons (SS). Sixteen participants (group 2) were present at the first session of MCQ: 6 R, 1 ER, 4 CF, 2 Pr, 2 SS and 1 indeterminate status. Finally, 12 participants (group 3) were present at the second session: 6 R, 1 ER, 1 CF, 1 SS and 3 indeterminate status. The results of"seniors" in Group 1 were higher than those of "juniors" at the first session. MCQ results for the second session were higher in the subgroup CF. A more marked progression in knowledge was observed in resident and Clinical Fellow. Finally, the score obtained by the group 3 was lower than in group 1. The format of the MCQ was particularly heterogeneous. The SCT will help to assess the capacity of decision making in a context of uncertainty (as unexpected surgery requiring quick decisions with immediate effect, surgical strategy in an unusual clinical situation). The different tools available would allow the establishment of an evaluation of teaching, but also to assess the development of thinking skills in situations of uncertainty. Their implementation will take place with the participation and support of the largest number of teachers in our specialty.

Myocardial revascularization in patients with severe ischemic left ventricular dysfunction. Long term follow-up in 141 patients

OBJECTIVES

The present study evaluates our experience with coronary bypass grafting in patients with EF < or =25%. Myocardial revascularization in this setting remains controversial because of concerns over operative mortality and morbidity and lack of functional and survival benefit.

MATERIALS AND METHODS

One hundred and forty-one patients with coronary artery disease and left ventricular ejection fraction < or =25% underwent coronary artery bypass graft between January 1988 and December 1998. Mean age at operation was 63.3 years and 81.4% were male. The major indication for surgery was angina (114 patients, 80.8%). Ejection fraction (EF), left ventricular end diastolic pressure (LVEDP) and cardiac index (CI) were used to assess left ventricular function. The number of graft was 2.7+/-1.6/patient. Internal mammary artery was used in 119 patients (84.3%). Intra aortic balloon pump was placed preoperatively in 25 patients (17.7%). Five operative risk factors were associated with a higher mortality: emergency, female sex, LVEDP, CI and NYHA class IV.

RESULTS

The operative mortality was 7% (10 patients). Left ventricular ejection fraction (assessed post operatively in 83 patients) improved from 22.2% preoperatively to 33.5% post operatively (P<0.001), mean end diastolic volume index fell from 98 to 83 ml/m(2) following surgery. Survival at 2, 5 and 7 years was respectively 84+/-3%, 70+/-4% and 50+/-5%. Two variables were associated with increased long term survival: congestive heart failure (NYHA class lower than IV (P=0.035) and cardiomegaly (P=0.04)

CONCLUSION

In patients with left ventricular dysfunction, myocardial revascularization can be performed relatively safely with good medium term survival and improvement in quality of life and in left ventricular function. Coronary artery bypass graft may be offered to patients with impaired ventricular function, but careful patient selection and management when considering these patients for operation should assess potentially reversible dysfunction.

Functional evidence for a role of vascular chymase in the production of angiotensin II in isolated human arteries

BACKGROUND

In human arteries, angiotensin-converting enzyme (ACE) inhibitors incompletely block the production of angiotensin (Ang) II from Ang I. This ACE-independent production of Ang II appears to be caused by serine proteases, one of which presumably is chymase. However, several serine proteases may produce Ang II, and the exact role of chymase in the vascular production of Ang II has never been directly evaluated using selective chymase inhibitors.

METHODS AND RESULTS

Rings of human mammary arteries were subjected to either Ang I or the chymase-selective substrate [pro,(11) D-Ala(12)] Ang I in the absence or the presence of the ACE inhibitor captopril, the serine protease inhibitor chymostatin, or the selective chymase inhibitor C41. Captopril only partially inhibited (by 33%) the response to Ang I. In the absence of captopril, C41 markedly reduced (by 44%) the response to Ang I, and this effect was identical to that of chymostatin. C41 also significantly reduced the response to Ang I in the presence of captopril, although this inhibitory effect was slightly less than that of captopril in combination with chymostatin. [Pro,(11)D-Ala(12)] Ang I induced potent contractions that were not affected by captopril but were abolished by chymostatin and markedly reduced by C41. In addition, we found that prior treatment of the patients with an ACE inhibitor did not affect the in vitro response to Ang I (in the absence or the presence of captopril) or to [Pro,(11)D-Ala(12)] Ang I.

CONCLUSIONS

Our results reinforce the hypothesis that chymase is a major serine protease implicated in the ACE-independent production of Ang II in human arteries.

[Acute traumatic rupture of the thoracic aorta and its branches. Results of surgical management]

STUDY AIM

The aim of this retrospective study was to report a series of 102 patients with acute traumatic rupture of the thoracic aorta and its branches (TRA) and to evaluate long-term results.

PATIENTS AND METHODS

From April 1977 to April 2000, 102 patients with RTA were admitted to our unit. Age ranged between 12 and 74 years (mean age: 33 years). Localisation was: ascending aorta (n = 3), aortic arch (n = 1), isthmus (n = 92), descending aorta (n = 1), innominate artery (n = 3), and left subclavian artery (n = 2). Associated injuries mainly included craniocerebral lesions (n = 76), rib fractures (n = 68), and thoracic (n = 38), and abdominal (n = 24) lesions. Average time between trauma and surgery was 37 hours. Aortography was used routinely for diagnosis. Five patients were inoperable; the procedure was delayed in three patients. In all but two patients with rupture of the isthmus, descending aorta and subclavian artery, the operation included venous arterial femorofemoral assistance. Rupture was partial in 37 patients (37 direct sutures), and complete in 55 patients (40 direct sutures). In two cases of left subclavian artery desinsertion, the operation included suture of the aortic tear and reimplantation of the artery. In patients with rupture of the ascending aorta and aortic arch, surgery was carried out under cardiopulmonary bypass with deep hypothermia for aortic arch rupture. Repair consisted of direct suture. In patients with rupture of the innominate artery, the lesion was treated under cardiopulmonary bypass by direct suture. In five cases, abdominal injuries required emergency procedure before aortic repair.

RESULTS

Four patients died. No postoperative paraplegia occurred. The high morbidity rate was in relation to the associated injuries. Among the 93 survivors, the aortic clinical status was satisfactory in 91 patients (two patients were lost to follow-up). Two patients died from cancer and myocardial infarction 2 and 7 years later respectively. One patient had prosthetic sepsis and was reoperated on with homograft. Angiographic control by aortography (n = 60) and angioMRI (n = 22) was normal in 76 patients. There were five stenoses at the level of the prosthesis, four with a gradient < 20 mmHg and one with a gradient > 50 mmHg and one aneurysm at the level of the isthmus. These last two patients were reoperated on with good result.

CONCLUSION

RTA remains a surgical emergency with multiple difficulties. Despite the development of new imaging modalities, angiography remains the gold standard for the work-up of these patients. Venous arterial femorofemoral assistance with a pump remains the best procedure in order to avoid paraplegia and vascular prosthesis implantation when possible. Endovascular stent graft insertion, although still under investigation, holds tremendous promise for non-surgical treatment of these patients.

Coarctation of the aorta in adults: surgical results and long-term follow-up

BACKGROUND

The aim of this retrospective study was to determine the impact of coarctation surgical repair on arterial blood pressure in adults more than 20 years of age.

METHODS

Thirty-five adults (23 men), mean age 28.1 +/- 5.7 years (range, 21 to 52 years), underwent coarctation surgical repair between 1977 and 1997. All patients had preoperative hypertension. Mean systolic blood pressure was 178 +/- 37 mm Hg (range, 110 to 230 mm Hg). Thirty-three patients were taking at least one hypertension medication at the time of operation. All patients had preoperative catheterization and angiography (mean gradient across the coarctation was 62 +/- 27 mm Hg [range, 32 to 130 mm Hg]). Operative technique was resection and end-to-end anastomosis for 30 patients, resection with Dacron (C. R. Bard, Haverhill, MA) graft for 4 patients, and a prosthetic bypass graft for 1 patient. There were no hospital deaths and no late morbidity.

RESULTS

All patients were reviewed. Follow-up was 165 +/- 56 months (range, 25 to 240 months). Of the 35 patients with preoperative hypertension, 23 were normotensive (systolic blood pressure < or = 140 mm Hg, diastolic blood pressure < or = 90 mm Hg) with no medication. Twelve patients were receiving medication: 6 required single-drug therapy and 6 patients required two drugs. Exercise testing was performed at an average of 6 +/- 4 months after repair and revealed hypertensive response to exercise in 8 of the 23 patients who were normotensive at rest and without medication. There were no recoarctation or repeat operations. Six aortic valve diseases were observed: three aortic incompetences (two bicuspid valves) treated by two valve replacements and one Bentall procedure, and three aortic stenoses (two valve replacements). No patient had evidence of a cerebrovascular accident.

CONCLUSIONS

Surgical repair of coarctation in adults has proved to be an effective procedure and significantly reduces arterial hypertension. However, long-term surveillance is mandatory and should include exercise testing to identify patients with potential hypertension.

[Aortic valve replacement in patients over 80 years of age. Short- and medium-term results in 140 patients]

One hundred and forty aortic valve replacements (AVR) performed between 1986 and 1995 at Rouen University Hospital in octogenarians (52 men and 88 women), including 9 emergency procedures, were analysed. One hundred and fifteen patients had pure aortic stenosis, 25 had mixed aortic valve disease with mainly aortic incompetence. The surgical decision was taken by the patient with the surgeon after an interview, in order to exclude too handicapped or undecided patients. Significant coronary artery disease was observed in 42% of cases. Isolated AVR was undertaken in 74% of cases and associated coronary bypass surgery in 23% of cases. Bioprostheses were used in 90% of cases. The valvular lesions were predominantly those of Monckeberg disease. The operative mortality was of 13 patients (9.3%). Functional recovery was satisfactory in 78% of cases; the average duration of the hospital stay was 12 days. All known risk factors for AVR: age, coronary lesions, cardiac failure, low ejection fraction, aortic regurgitation, were associated with insignificant increases in mortality. The secondary mortality was of 28 patients; 99 patients are still alive 4 to 91 months after surgery. The actuarial survival graph showed a 56.5% probability of 5 year survival. Eighty per cent of survivors live at home without loss of autonomy.

Aortic valvular replacement in octogenarians. Short-term and mid-term results in 140 patients

Aortic valvular replacements were performed between 1986 and 1995 at Rouen University Hospital on 140 octogenarians (52 male and 88 female). Pure or predominant aortic stenosis was present in 115 patients, 25 had associated aortic stenosis and insufficiency or predominant aortic insufficiency. Significant coronary lesions were present in 42% of patients. An isolated aortic valvular replacement was performed in 74% of patients, associated with a bypass in 23% and a bioprosthesis was used in 90%. Valvular lesions were mainly caused by Mönckeberg disease. Thirteen operative deaths occurred (9.3%). Functional recovery was satisfactory in 78%, mean hospital stay was 12 days. All well-known risk factors for aortic valvular replacement: age, coronary lesions, cardiac insufficiency, impaired ejection fraction and aortic insufficiency, led to an increase in operative mortality but were not statistically significant. Late mortality occurred in 28 patients, 99 patients are still alive at 4-91 months after surgery. The actuarial survival curve shows a 56.5% probability of surviving 5 years. Eighty per cent of survivors are able to live independently at home.

Urgent surgical repair of postinfarction ventricular septal rupture: early and late outcome

AIM

This retrospective analysis focuses on predictive factors of operative mortality and long-term survival after surgical repair of postinfarction ventricular septal rupture (VSR).

METHODS

Sixty-seven patients (43 males, 24 females) with VSR underwent surgical repair between December 1977 and December 1995. The site of the rupture was anterior in 44 patients and posterior in 23. The mean interval between myocardial infarction (MI) and VSR was 3.6+/-4.1 days. Clinical condition on admission was critical in 63 patients (49 in cardiogenic shock). An intra-aortic balloon pump was inserted preoperatively in 54 patients.

RESULTS

Operative mortality was 25% (17 patients). The main cause of death was cardiac failure. Factors influencing early deaths in univariate analysis were preoperative hemodynamic status (cardiogenic shock present in 30%; absent in 8%; p = 0.001), the location of the MI (anterior in 11.6%, posterior in 45.4%), the interval between infarction and surgery (<1 week was 33%, >1 week was 6.2%), and the response to initial active therapy. All patients were available for follow-up. The actuarial survival rates at 1 and 5 years are 74.6%+/-5.3% and 66.2%+/-6.2%, respectively. There were 12 late deaths and 40% were cardiac related. Two patients presented residual VSD (one reoperation). The left ventricular ejection fraction (LVEF) was mildly impaired in 9 patients. Three patients had moderate mitral insufficiency and two had moderate tricuspid insufficiency.

CONCLUSION

Repair of the postinfarction VSR remains a challenge. Improvement should be rendered possible by optimizing techniques. Postoperative morbidity is high, and these patients require intensive hospital resources. The late results have been satisfactory.

Pseudomonas aeruginosa coronary stent infection

Stent infection is a rare complication of coronary angioplasty. We report a case of a coronary stent bacterial infection due to Pseudomonas aeruginosa, shortly after implantation of the stent in the left circumflex artery, which presented as an acute pericarditis. Surgical treatment consisted of stent removal and partial excision of the circumflex artery without coronary artery bypass grafting.

Conventional and total orthotopic cardiac transplantation: a comparative clinical and echocardiographical study

OBJECTIVE

Clinical interest has recently emerged in a new technique of heart transplantation with bicaval and pulmonary venous anastomosis. This technique is thought to improve left heart function and reduce thromboembolism. We have used this technique systematically since 1993. We compared the patients transplanted before September 1993 with the standard technique and the patients transplanted with the new technique.

METHODS

A total of 135 patients were transplanted at our institution from 1987 to 1995, 100 with the standard technique and 35 with the new technique. of these, 95 survivors were studied by transthoracic and transesophageal echocardiography; 65 were transplanted with the standard technique ('standard' group) and 30 with the new technique ('total heart' group). All patients were free from rejection and in sinus rhythm when studied.

RESULTS

Boths groups were similar in pretransplant characteristics. Operative data were similar with a limited increase in the ischemic time with the total heart technique (210 +/- 73 min for 'total heart' vs. 196 +/- 84 min for 'standard'). Right heart catheterization showed comparable cardiac output and pulmonary pressures. Peripheral embolic events occured in 9 patients in the 'standard' group and none in the 'total heart' group. The left atrium was larger in the 'standard' group (58 +/- 6 vs. 42 +/- 4 mm, P = 0.0006). Left atrial spontaneous echo contrast was present in 32 patients in group 'standard' and none in 'total heart' group (P < 0.0001), and left atrial thrombi were detected in 17 patients in group 'standard' vs. none in group 'total heart' (P = 0.01). All patients with a history of embolism had left atrial thrombus and spontaneous echo contrast.

CONCLUSION

This study showed a high incidence of left atrial spontaneous echo contrast and thrombi when using the standard technique, which was absent when using the total heart technique. Total heart transplantation with bicaval and pulmonary venous anastomosis should be preferred for heart transplantation.

How to protect hypertrophied myocardium? A prospective clinical trial of three preservation techniques

Protection of the hypertrophied myocardium during heart surgery is still a controversial matter. We prospectively studied 3 currently available preservation techniques in 60 patients operated on for isolated aortic stenosis. Patients were randomly assigned to one of the following groups: CWB: continuous warm blood cardioplegia ICB: intermittent cold blood with warm blood controlled reperfusion Cryst: intermittent cold crystalloid cardioplegia (SLF11, Biosédra Laboratory, Vernon, France). All groups were matched for age, ejection fraction, NYHA class, aortic valve surface, and operative risk score. There were no deaths. No statistically significant difference was found among the groups in terms of ventilatory support time, ICU stay time, hospitalization or atrial fibrillation occurrence. Blood gases in the coronary sinus at the time of clamp release showed deep acidosis with crystalloid cardioplegia (pH = 7.11 vs 7.39 for CWB and 7.38 for UCB, p < 0.0001) associated with a higher lactate production than in the other groups (1.3 mmol vs 0.5 for CWB and 0.58 for ICB, p < 0.0001). Acidosis was corrected at the end of bypass with no significant differences among groups. CK-MB samples were taken on arrival in ICU, then 6 and 24 hours later. These samples showed much higher levels with cold blood (H6: 70 mcg/l vs 33 for CWB and 45 for Cryst, p = 0.0019). Although the 3 types of cardioplegia may be safely used for isolated aortic stenosis surgery, continuous warm blood cardioplegia appears to be the best choice.

[Coronary bypass in patients with severe left ventricular dysfunction (EF < or = 25%). Apropos of 111 patients]

One hundred and eleven patients with severe left ventricular dysfunction (EF < or = 25%) underwent coronary bypass surgery between January 1984 and December 1994. The selection criteria were based on the measurement of an EF < or = 25%, LVEDP and CI. All patients had angina and 83 had signs of pulmonary oedema or episodes of congestive failure. Patients with valvular disease, left ventricular aneurysms, reoperations, surgery for arrhythmias and prior angioplasty, were excluded. The coronary disease usually involved all three vessels. Seventeen patients had lesions of the left main stem associated with lesions of the right coronary artery. The average number of bypass grafts was 2.6 +/- 1.6 per patient. The average duration of aortic clamping was 60 +/- 19 minutes. Operative mortality (first month after surgery) was 10 patients (9%). The operative risk factors were: gender, stage of cardiac failure, emergency surgery, LVEDP > 23 mmHg (p < 0.05), CI < 21/min/m2 (p < 0.05). The mean follow-up period was 42 +/- months (3 lost to follow-up). Late mortality was 42 patients. The one year actuarial survival was 88 +/- 5.3%, 76 +/- 9% at 3 years, and 56 +/- 18% at 6 years. Long-term functional results were related to: preoperative stage of cardiac failure (NYHA stage IV) and the association of raised LVEDP and low CI. Surgical results remained satisfactory, however, and the surgical indication was justified in selected patients despite severe left ventricular dysfunction in cases usually with stable invalidating or unstable angina, in the knowledge that myocardial deterioration is progressive in the medium-term with a high incidence of cardiac failure.

[What myocardial protection to select for isolated aortic valve replacement? A clinical prospective study of 3 cases of cardioplegia]

Isolated stenosis of the aortic valve leads to left ventricular hypertrophy which makes myocardial protection difficult during cardiac, surgery and the choice of optimal cardioplegia remains controversial. The authors compared three protocols of cardioplegia in patients operated for isolated aortic stenosis with left ventricular hypertrophy. Sixty consecutive patients with these criteria were randomly attributed to one of the three following groups (20 in each group): cardioplegia with continuous warm blood; cardioplegia with intermittent cold blood with warm reperfusion; cardioplegia with intermittent cristalloid using SLF11 solution. The preoperative data was comparable in three groups. There were no deaths. Patients undergoing cardioplegia with warm blood came off cardio-pulmonary bypass more quickly (15 mn vs 21 mn for the other groups, p = 0.03). Cristalloid cardioplegia was associated with major acidosis in coronary sinus blood when the aorta was declamped (7.11 vs 7.38 for cardioplegia with cold blood and 7.39 for cardioplegia with warm blood, p < 0.0001) but with a low postoperative CPK-MB rise. Cardioplegia with cold blood induced higher CPK-MB liberation than the other forms of cardioplegia (at H-, 63 mcg/L vs 33 for warm blood and 45 for cristalloid cardioplegia, p = 0.0019). None of the protocols tested prevented myocardial lactate production at aortic declamping. Cardioplegia with warm blood offers therefore the best protection for hypertrophied myocardium during simple aortic valve replacement but it does not maintain strictly aerobic metabolism.

Mitral valve reconstruction: long-term results of 120 cases

Between January 1977 and December 1992, 120 patients underwent mitral valve reconstruction for pure mitral valve regurgitation (n = 88), or associated with mitral stenosis (n = 32). The mean age was 57.6 years. Some 89 patients were in New York Heart Association (NYHA) class III and IV; 61% were in atrial fibrillation. Four mechanisms of mitral regurgitation were assessed: dilatation of the annulus (group I: n = 10); increased amplitude of valve motion (group II: n = 62); restriction of valve motion (group III: n = 23), and mixed lesions (group IV: n = 25). Mitral valve repair was carried out using techniques described by Carpentier. Ring annuloplasty was performed in all patients. There were two operative deaths, and six late deaths. Mean patient follow-up was 41 (range 2-142) months. The actuarial survival rate, excluding hospital deaths, was 91.7% at 5 years and 89.1% at 8 years. Actuarial freedom from reoperation at 8 years was 95(2)%. Freedom from all thromboembolic complications was 89.1% at 8 years. Most survivors had improved to NYHA class I or II and postoperative Doppler echocardiography revealed satisfactory mitral valve competence in 83 patients. Mitral valve reconstruction for mitral regurgitation using Carpentier techniques provides excellent long-term functional results and should be considered as the procedure of choice in patients referred for mitral regurgitation.

Aortic valve replacement after aortic valvuloplasty for calcified aortic stenosis

OBJECTIVE

This study concerns patients who underwent one or several aortic balloon valvuloplasties at our institution and subsequently required cardiac surgery, either on an emergency basis after aortic valvuloplasty or due to the development of aortic stenosis.

METHODS

Between February 1987 and December 1993, 137 patients (73 male, 64 female, mean age 72 +/- 9 years) underwent aortic valve replacement for calcified aortic stenosis after several percutaneous balloon aortic valvuloplasties. Thirty-one patients were in NYHA stage II, 70 in stage III and 36 in stage IV. Seventy patients had angina (23 stage I or II, 47 stage III or IV) and 24 patients presented syncope or lipothymia. Twenty-three percent had at least two of these three symptoms. The indications for balloon dilatation were non-definitive surgical contraindication or high surgical risk (73), personal choice (49), refusal of surgery (9) and emergency (5:2 massive aortic regurgitation, 1 left ventricle perforation, 1 cardiogenic shock, 1 endocarditis in cardiogenic shock). Seven patients received preoperative aortic valvuloplasty due to a very high operative risk. The average time between dilatation and surgery was 472 days and there was clinical improvement for an average period of 261 days. The aortic valve replacements consisted of 58 mechanical prostheses and 79 xenografts with 22 concomitant procedures.

RESULTS

Operative mortality was eight patients (5.8%). During the follow-up (17.4 +/- 9.2 months), four patients died (3.6%), 91.2% of the patients were in class I and II and 95% were without angina. The actuarial survival rate was 90.5 +/- 6.6% including hospital mortality.

CONCLUSIONS

Both our experience and the literature show that balloon aortic valvuloplasty is followed by an immediate improvement in hemodynamic status with a decrease in valve gradient and an increase in valve area. However, the hemodynamic benefit is typically short-lived with a very high restenosis rate. Balloon aortic valvuloplasty is not an alternative to aortic valve replacement, which remains the best treatment for calcified aortic stenosis; the benefits and long-term results of aortic valve replacement are well established, even in the elderly.

Standard orthotopic heart transplantation versus total orthotopic heart transplantation. A transesophageal echocardiography study of the incidence of left atrial thrombosis

BACKGROUND

After standard orthotopic heart transplantation (Sd HT), the enlarged resultant atria may promote atrial thrombosis. The purpose of this study was to compare the incidence of spontaneous echo contrast and left atrial thrombosis after Sd HT and total orthotopic (Tot HT) heart transplantation.

METHODS AND RESULTS

Transesophageal echocardiography (TEE) was performed in 75 patients with Sd HT and in 20 patients with Tot HT. Despite the use of antiplatelet therapy, an acute arterial embolism occurred in 11 (15%) of the 75 patients with Sd HT but in none of the 20 Tot HT patients. All patients were in sinus rhythm. Left ventricular ejection fraction was similar in Sd HT and Tot HT patients. Left atrial diameter was smaller in Tot HT patients than in Sd HT patients (41 +/- 4 versus 58 +/- 6 mm, P < .001). In Sd HT patients, spontaneous echo contrast was present in 43 patients (57%) and was associated with left atrial thrombus in 20 patients (on the left atrial appendage in 12 patients, on the posterior wall in 6, and on the suture in 2). No thrombus was detected by transthoracic echocardiography; all thrombi were detected by TEE. On the other hand, no left atrial thrombus was observed in Tot HT patients, and only 1 patient had spontaneous echo contrast. Of the 11 Sd HT patients who experienced an arterial embolism, 5 had both spontaneous echo contrast and left atrial thrombus and 5 had only spontaneous echo contrast.

CONCLUSIONS

This study demonstrates a high rate of left atrial thrombus after Sd HT and emphasizes the role of TEE in the follow-up of these patients. The therapeutic implications are the need for a preventive anticoagulant therapy in the high-risk population receiving Sd HT diagnosed with TEE and the consideration of Tot HT as a better surgical approach as far as thrombotic complications are concerned.

Dobutamine stress echocardiography in orthotopic heart transplant recipients. VACOMED Research Group

OBJECTIVES

This study sought to determine whether dobutamine stress echocardiography could accurately identify coronary artery disease after heart transplantation.

BACKGROUND

After heart transplantation, coronary artery disease is related to either diffuse concentric intimal thickening or focal stenosis and may be underdiagnosed by coronary angiography.

METHODS

We enrolled 41 patients, a mean (+/- SD) of 40 +/- 20 months after heart transplantation, at the time of their routine control coronary angiogram. Three patients were excluded because of poor echogenicity on the angiogram and one because of ventricular premature beats. Standard echocardiographic views were acquired at baseline and at incremental dobutamine infusion levels (from 5 to a maximal dose of 40 micrograms/kg body weight per min at 3-min intervals). Regional wall motion score was calculated from a 16-segment model, and each segment was graded from 1 (normal) to 4 (dyskinesia). Coronary angiography was performed 24 h after dobutamine stress echocardiography, and angiograms were analyzed in blinded manner.

RESULTS

Twenty-three (62%) of 37 patients had normal coronary angiographic findings. Dobutamine stress echocardiography showed abnormalities in only 2 of 23 patients. Fourteen patients (38%) had abnormal angiographic findings, seven of whom had stenoses > 50%. Dobutamine stress echocardiography correctly identified the corresponding hypoperfused segments in these seven patients. More of interest were the other seven patients, of whom three had angiographic nonsignificant stenoses (< 50%), and four had minor diffuse coronary irregularities. Dobutamine stress echocardiography showed hypokinesia in five of these seven patients despite nonsignificant lesions at coronary angiography. The respective overall sensitivity and specificity of dobutamine stress echocardiography were 86% and 91%. At follow-up, 2 of the 37 patients had an acute myocardial infarction. Both had abnormal findings on dobutamine stress echocardiography: One had normal coronary angiographic results, and one had significant coronary lesions.

CONCLUSIONS

Dobutamine stress echocardiography is a useful technique for the diagnosis of coronary artery disease after heart transplantation. These preliminary results indicate that dobutamine stress echocardiography may have a predictive value for further ischemic events in heart transplant recipients.

[Right atrial thrombosis; an unusual late complication of the Fontan procedure. Apropos of a case]

The authors report the case of a large right atrial thrombosis causing acute cardiac failure in an 18 year old patient with tricuspid atresia who had undergone 3 operations: Waterston shunt at 2 months of age, Fontan procedure at 3 years of age with reoperation at 13 years of age. The diagnosis was made at echocardiography and angiography. Surgical management comprised ablation of the thrombus and a tunneling of the right atrium between the inferior vena cava and the atriopulmonary conduit. The immediate postoperative course was complicated by a slowly regressive neurological deficit. The medium-term outcome (one year) is satisfactory with antiarrhythmic and anticoagulant therapy. A review of the literature showed that these thromboses are not exceptional in the early postoperative period for a variety of reasons. Secondary thrombosis is often related to arrhythmias, thus requiring clinical, electrocardiographic and echocardiographic follow-up of these patients and the prescription of antiarrhythmic and anticoagulant therapy. The diagnostic methods are discussed. Echocardiography may be sufficiently explicit to make potentially risky angiography unnecessary.

[Reoperation for heart valve prosthesis. Apropos of 99 cases]

From March 1977 to November 1988, 99 patients were reoperated on after a first valvular replacement. Mean delay between the two operations was 53 months (10 days to 18 years). The patients were reoperated on mainly for mechanical disinsertion (30), bacterial endocarditis (25) and thrombosis (18 patients). Operative mortality was 11%, mainly following reoperation for bacterial endocarditis. Mean follow-up (85 patients) was 49 months (6 months-11 years). 75% were alive and doing well 4 years after reoperation and 66% at 6 years. Eight patients needed a third operation with two deaths.

[Prevalence of intra-auricular thrombi detected by transesophageal echocardiography in patients with cardiac transplants]

The aim of this study was to determine the prevalence of intra-atrial thrombi or spontaneous contrast by transoesophageal echocardiography in patients who underwent cardiac transplantation by Lower and Shumway's technique. Transoesophageal echocardiography was performed in 52 transplant patients (43 men, 9 women: average age 51 years) with a high frequency biplane transducer. After surgery, all patients received platelet antiaggregant therapy. Despite this treatment, 4 patients had a sudden systemic embolic episode and were then placed on oral anticoagulants. All patients were in sinus rhythm at the time of the examination and some had signs of acute rejection on endomyocardial biopsy performed the same day. Spontaneous contrast was observed in 27 patients (52%) and was associated with thrombosis in 15 patients (29%). These thrombi were located in the left atrial appendage in 8 cases, on the left atrial posterior wall in 5 cases and on the left atrial sutures in 2 cases. None of these thrombi had been detected by transthoracic echocardiography. No significant difference was observed between those with and those without thrombosis with respect to left atrial dimensions, left ventricular ejection fraction, cardiac index, pulmonary pressures and the number of episodes of acute rejection. The 4 patients with a history of arterial embolism all had an intra-atrial thrombus. This study demonstrates a high incidence of spontaneous contrast and intracardiac thrombi in the dilated left atrium of patients transplanted by Lower and Shumway's technique. It also underlines the value of transoesophageal echocardiography in the follow-up of transplant patients.(ABSTRACT TRUNCATED AT 250 WORDS)

Surgical treatment of infected composite graft after replacement of ascending aorta

Infection of a composite graft is a serious complication. However, reports of such cases are rare even in large series. We report our experience with 4 patients in whom infection of a composite graft developed with pseudoaneurysm formation. Two of the patients had Marfan's syndrome and were treated by Bentall procedure and 2 were treated by Cabrol technique for non-Marfan cystic medial necrosis. Staphylococcus epidermidis was detected in 2 patients and Enterococcus in 1. Reoperation was carried out between 1 and 32 months after the first intervention. One patient died of cerebral embolism and 3 remained free of infection 11 to 82 months later. These cases and guidelines for managing abdominal and peripheral vascular prosthetic infection indicate the need for prompt reintervention when infection is suspected from chronic sepsis, septicemia, positive blood cultures, fistula, anastomotic leak, hemolysis, embolism, graft deformity, or false aneurysm. When the organism is isolated, appropriate antibiotic therapy should be administered. All prosthetic material should be removed and all adjacent infected or necrotic tissue excised. Local antiseptic irrigation may be helpful. Dead space around the prosthesis should be filled with well-vascularized transposed pedicled flaps. Antibiotic therapy should be intravenously administered for at least 6 weeks.

[Aortic valve replacement after aortic valvuloplasty for calcified aortic stenosis. A propos of 104 patients]

Between February 1987 and December 1990, 104 patients (48 men, 56 women) with an average age of 69 years, underwent aortic valve replacement (AVR) after one or several percutaneous aortic valve balloon dilatation. Thirty one patients were in Class II and 73 patients in Classes III and IV. Twenty two patients had angina (16 Class I-II, 6 Class III-IV) and 12 patients had syncope or near syncope on effort. The indications of valvuloplasty were: non-definitive contraindications of surgery or a surgical risk which was estimated to be excessive (46 patients), a personal choice (41 patients). Five patients underwent preoperative dilatation because of the high operative risk; 7 patients refused surgery and 5 patients were operated as an emergency (2 mas-sive aortic regurgitations, 1 left ventricular perforation, 1 cardiogenic shock, 1 endocarditis with cardiogenic shock). The inter-val between dilatation and surgery was on average 472 days. The patients were improved over an average period of 261 days. Apart form the emergency cases, the patients were operated because of restenosis. Surgery consisted of 53 mechanical and 51 bioprosthetic valve replacements. There was an associated procedure in 17 cases (17 single bypass grafts, 2 double bypass, 1 triple bypass graft, 1 left ventricular suture, 1 Bigelow procedure, 2 mitral valve replacements, 1 tricuspid annuloplasty, 1 carotid endarteriectomy, 1 replacement of the ascending aorta, 1 closure of ASD). The operative mortality was 7 patients (6.7%). The operative findings were 8 lesions related to dilatation, mainly valve tears or disinsertions requiring rapid (6 cases) or emergency (2 cases) surgery for massive aortic regurgitation.(ABSTRACT TRUNCATED AT 250 WORDS)

Intraoperative coronary angioscopy--technique and results: a study of 38 patients

Over a period of 11 months, 38 patients submitted to coronary artery revascularization underwent intraoperative angioscopy of the coronary arteries and internal thoracic arteries. Fifty-nine lesions were observed, but only 31 stenoses responsible for coronary insufficiency were observed (33%). Forty-four distal anastomoses were explored (47%) but ten of these explorations were incomplete. None revealed technical failure of the anastomosis. Thirteen harvested left internal mammary arteries were explored. One of the explorations led to rejection of the graft due to an intimal fracture. Some tiny intimal flaps were observed in our experience, as in others. Although the iatrogenic origin of these lesions in relation to the introduction of the angioscope is obvious, it does not seem to influence the outcome of the operation. In our opinion, two main fields appear to be developing in coronary angioscopy: preoperative assessment of the quality of internal thoracic artery grafts, and control of distal graft anastomoses. The flexibility of the angioscopes and of the leading catheters must be improved to minimize the risk of arterial wall traumatic lesions.

[Reoperations on heart valve prosthesis. Apropos of 99 cases]

From March 1977 to November 1988, 99 patients were reoperated on after a first valvular replacement. Mean delay between the two operations was 53 months (10 days to 18 years). The patients were reoperated on mainly for mechanical disinsertion (30), bacterial endocarditis (25) and thrombosis (18 patients). Operative mortality was 11%, mainly following reoperation for bacterial endocarditis. Mean follow-up (85 patients) was 49 months (6 months-11 years). 75% were alive and doing well 4 years after reoperation and 66% at 6 years. Eight patients needed a third operation with two deaths.

Acute traumatic isthmic aortic rupture. Long-term results in 49 patients

Forty-nine patients who sustained acute traumatic rupture of the aorta at the level of the isthmus were treated in our hospital between 1976 and 1990. Four patients died before surgery and 45 patients were operated upon using a pump oxygenator partial bypass in all but 2 cases (1 clamp and sew and 1 shunt). The tear was circumferential in 33 and partial in 12 cases. Direct suture was used in the 12 partial and in 21 of the circumferential tears. A dacron tube was used in 12 patients. Hospital mortality was 3 resulting from brain damage, prolonged shock before surgery and necrosis of the colon 4 weeks after operation. No paraplegia was observed. There were 2 cases of neurological disturbance (2 spinal cord dysfunction 5 and 8 days, respectively, after surgery). These complications were transient. Among the 42 survivors, 1 was lost to follow-up. The clinical aortic status of the remaining 41 was excellent. Aortic reconstitution as assessed by digital aortic angiography was excellent in the 33 cases examined with 2 exceptions (graft stenosis, false aneurysm). Our experience and review of a large series indicate: the use of a partial bypass with pump oxygenator decreases the probability of medullary ischemia, but the risk of spinal cord ischemia is not eliminated. When intra-abdominal lesions are life-threatening, laparotomy must preceed thoracotomy. Clinical results assessed in long-term survivors are excellent, especially after direct repair.

[EEG in elderly cardiac patients without cerebral lesions]

Ageing is known to be accelerated by risk-factors. The continuity between normal and pathological ageing is still quite disputed. Concerning cerebral ageing, the use of statistical methods on electroencephalographic (EEG) parameters appeared to be interesting. In this study, three different groups of elderly subjects were examined by EEG: normal subjects without neurological nor cardiac disease, subjects with Alzheimer-dementia (AD) and cardiac patients without cerebral clinical signs. Stepwise discriminant analysis showed that EEG-parameters discriminating normal subjects from cardiac patients were different from those discriminating AD-patients from normal. Furthermore, AD-patients could be well-discriminated from elderly cardiac patients.

[Spontaneous rupture of subclavian artery disclosing Ehlers-Danlos disease. A case]

The authors report the case of a 30-year old man who suffered spontaneous rupture of the right subclavian artery. Treatment consisted of carotid-axillary graft since the fragility of the vessel precluded direct suture. The clinical symptoms, together with histological and ultrastructural examinations led to a diagnosis of Ehlers-Danlos syndrome with purely arterial manifestations.

[Aneurysm of the membranous ventricular septum. Apropos of 4 cases surgically treated]

Four patients with aneurysms of the membranous ventricular septum were operated either because of complications or for associated malformations. The authors describe the anatomical, radiological and, above all, the echocardiographic and angiographic features of this malformation. Surgical management is necessary in complicated cases or when there are associated congenital malformations. The information provided by echocardiography in the diagnosis and follow-up of ventricular septal defects indicates that this malformation is not as rare as was previously thought.

[Congenital aortic valve stenosis treated by dilatation. Apropos of a case with hemodynamic control 12 months later]

Intraluminal dilatation of congenital aortic valve stenosis was attempted in a 14-year old boy. Significant improvement was obtained, with a fall in transaortic gradient from 80 to 30 mmHg. A control haemodynamic examination performed 12 months later confirmed that the result was stable; there was no aortic leakage, and myocardial hypertrophy had begun to regress at echocardiography. This case is of interest in that dilatation is less costly than surgical commissurotomy. However, this technique cannot be widely used until satisfactory long-term results have been demonstrated in a large population of children.

A case of spontaneous incomplete non-traumatic rupture of the ascending aorta with acute aortic insufficiency (successful emergency surgical repair)

Spontaneous incomplete non traumatic rupture of the ascending aorta is rare but life-threatening; it may well remain unnoticed until emergency surgery becomes necessary. Its possibility should be considered in all patients presenting signs of tamponade, chest pain or aortic regurgitation, and it must be diagnosed by appropriate procedures.

Valve replacement in acute native valve endocarditis

From 1974 to 1984, 46 patients underwent emergency surgery for acute native valve endocarditis. Urgent valve replacement was necessary because of rapid hemodynamic deterioration in 34 (73%), uncontrolled sepsis plus heart failure in 9 (19%), and life-threatening emboli in 3 (7%) patients. At the time of surgery 23 patients (50%) were in NYHA functional class IV, 20 in Class III, and 3 in class II. Streptococcus was the most common organism encountered, followed by staphylococcus. Thirty-four cases presented severe aortic regurgitation, 3 mitral incompetence, 8 mitral plus aortic insufficiency, and one aortic plus tricuspid insufficiency. Operative mortality rate was 17% (8/46). Most deaths were due to preoperative multiple system deterioration, especially in cases with lesions of both the aortic and mitral valves, and were unrelated to the duration of preoperative antibiotic therapy. The postoperative observation period of long-term survival is from 6 to 102 months (= 44 months). There were 7 late deaths. The actuarial survival, including operative mortality, is 67%. Twenty-two patients are now in NYHA class II, 6 in class III. The duration of postoperative antibiotic treatment (6 weeks in our series) seems to be important for the prevention of reinfection, early surgery is of great benefit; our 31 survivors showed an excellent clinical improvement.

[Spontaneous incomplete rupture of the supra-sigmoidal aorta presenting as aortic insufficiency. Apropos of an emergency surgical case]

We report a case of spontaneous incomplete rupture of the first segment of the ascending aorta presenting as aortic incompetence and acute tamponade confirmed by preoperative angiography in a 57 year old hypertensive woman. This patient underwent emergency conservative surgery with good results at 8 months' follow-up. This rare pathology occurs in the same terrain as dissection of the aorta. The diagnosis should be suspected not only when chest pain and/or aortic incompetence are associated or not with acute tamponade, contrasting with a normal electrocardiogram, but also in atypical presentations which necessitate angiography in multiple incidences in order not to miss the diagnostic signs which are often invisible in the standard projections. When there are no complications, this condition may pass undiagnosed. However, in most cases, it leads to acute tamponade due to intrapericardial rupture or to an aortic aneurysm or aortic incompetence. The latter complications are usually associated with severe regurgitation requiring surgical correction, which in some cases may be conservative.

[Results of surgical treatment in acute native endocarditis. Apropos of 41 patients]

This study was based on the analysis of 41 cases of infectious endocarditis of native valves operated during the acute phase. Patients with bacteriological cures, prosthetic valve endocarditis and endocarditis on congenital non-valvular lesions were excluded. There were 32 men and 9 women with an average age of 49 years. The valve lesions were aortic incompetence, mitral incompetence, mitro-aortic disease and mitro-tricuspid disease. Fourteen patients had preexisting valvular disease (rhumatic in 12 and congenital in 2 cases). These patients were in an advanced clinical state at the time of operation: 23 Class IV, 16 Class III and 2 Class II operated for systemic embolism. The surgical indications were severe cardiac failure in 30 cases, systemic embolism in 2 cases and persistance of septicaemia with worsening cardiac function in 9 cases. The causal organism was isolated from blood cultures in 34 cases (83%) and from the excised valve in 13 cases. The early postoperative mortality during the first month was 5 patients (3 cases of aortic incompetence associated with mitral incompetence and 2 cases of aortic incompetence alone). Death was caused in most cases by irreversible cardiac failure related to the advanced preoperative cardiac failure. All the other patients were followed up for 1 to 102 months (average 44 months). There were 7 late postoperative deaths. The mortality rate was 3.4% per patient year including patients undergoing chronic haemodialysis. The actuarial survival was 79% at 78 months excluding the operative mortality.(ABSTRACT TRUNCATED AT 250 WORDS)

[Aortic stenosis with low preoperative ejection fraction. Long-term postoperative hemodynamic and angiographic studies]

Twenty-two patients underwent aortic valve replacement for aortic stenosis with a preoperative ejection fraction less than 45%. Three patients died peroperatively and a fourth patient died 18 months later before the haemodynamic control. The other 18 patients were systematically reinvestigated, on average 16 months after surgery. Sixteen had a remarkable functional improvement and a significant increase in ejection fraction at haemodynamic control: 32 +/- 6% to 61 +/- 8%, p less than 0.001. They were surgical successes (Group I). In this group, the 7 patients with the most severe alteration of ventricular function and an average ejection fraction of: 26 +/- 3%, also improved to near normal function with a postoperative fraction of 62 +/- 11%. There was no significant improvement of the ejection fraction in 2 patients, and they were classified with the fatalities as surgical failures (Group II). The clinical, electrocardiographic, radiological, haemodynamic and angiographic data of these two populations were compared to try and identify preoperative indices of prognostic value. Only the angiographic left ventricular myocardial mass index (LVMI) was significantly higher in Group II (253 +/- 98 g/m2) than in Group I (156 +/- 56 g/m2, p less than 0.05). A discriminating analysis showed that the most important parameters to separate the 2 groups of patients were the LVMI and the thickness of the left ventricular wall. The marked increase of the postoperative ejection fraction in 3/4 of our patients confirmed the clinical value of valvular replacement justifying the indication for surgery in patients with severe aortic stenosis in spite of a severe alteration of left ventricular function.

Comparative evaluation of aortic valve replacement with Starr, Björk, and porcine valve prostheses

Three groups of 100 consecutive patients with aortic valve disease who were operated on between 1974 and 1978 underwent long-term evaluation. There were 100 aortic valve replacements with porcine bioprosthetic valves (group I), 100 with Starr valves (group II), and 100 with Björk valves (group III). There were no significant differences in the preoperative clinical conditions of the patients in the three groups. Cumulative follow-up was 1688 patient-years. Incidence of valve-related death at 8 years was 4 +/- 2.3% in group I, 13 +/- 3.6% in group II, and 13 +/- 3.8% in group III (p less than .05). At 8 years 95 +/- 2.8% of the patients in group I were free of thromboembolism, compared with 81 +/- 4.8% of those in group II and 84 +/- 4.2% of those in group III (p less than .002). The actuarial risk of a reoperation at 8 years was 16 +/- 6% in group I, 5 +/- 2% in group II, and 2 +/- 1.6% in group III (p less than .025 group I vs group III). At 8 years 98 +/- 1.2% of the patients in group I were free of anticoagulant-related complications, compared with 88 +/- 3.8% of those in group II and 86 +/- 3.9% of those in group III (p less than .005). We conclude that at 8 years porcine bioprosthetic valves performed better than mechanical valves, taking into consideration thromboembolism, anticoagulant-related hemorrhage, and valve-related death.

[Comparative evaluation of various methods of treatment of mitral valve diseases. Apropos of 4 series of 100 patients operated on using the Starr prosthesis, Bjork prosthesis, bioprosthesis and valve reconstruction]

The results of 4 groups of 100 patients undergoing mitral valvuloplasty (group I), isolated mitral valve replacement by a bioprosthesis (group II), a Starr-Edwards prosthesis (group III) and a Björk prosthesis (group IV) between 1974 and 1977 were compared. The selection of patients for each group was identical and made according to strict criteria. The average age was between 47.1 +/- 12.5 years and 51.8 +/- 10.5 years according to the particular group; the average functional classification was 2.4 +/- 0.4 to 2.5 +/- 0.6; the average cardiothoracic ratio was 0.58 +/- 0.07. Most patients were in atrial fibrillation. Ninety-seven per cent of patients were followed-up by questionnaires. The results were expressed with respect to simple clinical events used in all previously reported series. The long-term mortality was identical in the 3 groups undergoing valve replacement (40 p. 100 at 7 years) but was much less in the group undergoing valvuloplasty (18 p. 100 at 7 years). The mortality rate due to valvular problems was significantly less in the valvuloplasty group (2 p. 100 at 7 years) than in the groups with mechanical prostheses (20 p. 100 at 7 years). Intermediate results were observed in the bioprosthetic group (9 p. 100 at 7 years). Thrombo-embolism was significantly less common in the groups undergoing valvuloplasty and bioprosthetic valve replacement (2 p. 100 and 6 p. 100 at 7 years) than in the group with Starr-Edwards and Björk prostheses (30 p. 100 and 32 p. 100 at 7 years).(ABSTRACT TRUNCATED AT 250 WORDS)

Comparative evaluation of mitral valve repair and replacement with Starr, Björk, and porcine valve prostheses

Four hundred consecutive patients with isolated mitral valve disease who were operated on between 1974 and 1977 underwent long-term evaluation. In this group there were 100 valve repairs, 100 porcine valves, 100 Starr valves, and 100 Björk valves. There were no significant differences in the preoperative clinical conditions of the patients in the four groups. Cumulative follow-up was 2058 patient-years. We concluded from the data that mitral valve repair was associated with fewer valve-related complications than valve replacement. Thromboembolism was the most significant parameter with respect to determining long-term results of the use of the porcine, Starr, and Björk valve prostheses.

Healing of biodegradable vascular prosthesis. Incorporation of 3H-valine into proteins in the subendothelial scar and host intima-media of rat aorta

Heparin treated and aldehyde crosslinked rat aorta segments were implanted in infrarenal aorta of homologous rats. One year following aortic replacement, the subendothelial scar and the prosthetic remnants were excised. The scar and the host intima-media were incubated with 3H-valine for 4 h and extracted with 5 M guanidinium chloride--0.05 M dithiothreitol--0.1 M Tris--0.1% EDTANa2 at pH 7.5 prior (Extract 1) and following (Extract 2) hydrolysis of collagen. The radioactivity of extract 1 accounted for approximately 80% of the total label incorporated in the scar and host intima-media. The 3H-label of extract 1 adjusted for the tissue collagen content was about twenty times higher in the scar than in the host aorta. The major 3H protein peaks from Extract 1 of scar and host aorta were of 130 K, 100 K and 70 K apparent molecular weight, based on polyacrylamide gel electrophoresis in SDS. Hydrolysis with 2N KOH of the extraction residue from the host aorta and scar yielded 3H-val-pro dipeptides and hydrolysis with 6N HCl desmosines. The incorporation pattern of 3H-valine into proteins and the presence of elastin synthesized de novo in the scar replacing the prosthesis indicate macromolecular repair of the host aortic wall.

[Oesophagectomy without thoracotomy. 5 cases (author's transl)]

The authors describe an original technique of excision in severe caustic burns of the upper digestive tract: oesophagectomy without thoracotomy. The new procedure avoids the wide pleural opening of the thoracic approach, which leads to frequent and often fatal respiratory and infectious complications, whereas extrapleural drainage of the mediastinum has always proved effective and safe. Five technically successful operations were performed in one year. One patient died on the 10th post-operative day of tracheal necrosis related of the burn and 4 patients survived. These preliminary results are encouraging.