Endovascular treatment of an aneurysm of the descending thoracic aorta in a heart transplant recipient: long-term result.

Heart-transplanted patients have a known higher incidence of aortic aneurysms. However, there is paucity of information regarding thoracic localisation in this clinical setting and of the endovascular option in such patients with chronically high level of immunosuppressive agents. We describe long-term follow-up of a 72-year-old man who developed an aneurysm of the descending part of the thoracic aorta 10 years after an orthotopic cardiac transplantation. Because of comorbid medical conditions, classical open-chest procedure could not be performed. An alternative treatment by endovascular repair was applied successfully and allowed a perfect exclusion of the aneurysm. Chronically high level of immunosuppressive agents seems not to be a contraindication to the endovascular option. Consequently, extended cardiovascular screening of heart-transplanted patients is desirable to facilitate early detection and elective endovascular repair.

Parachute-like technique for off-pump implantation of cardiac support device in isolated and combined procedure.

Cardiac support is a new and promising therapy for refractory heart failure. Only a few previous publications focused on technical implantation of such device. We have developed a new technique that facilitates a consistent and safe implant when the procedure is done without extra-corporeal circulation (ECC). Herein, we report our experience of 60 consecutive CorCap cardiac support device (Acorn Cardiovascular, USA) implantations off-pump for both isolated and combined implantation.

Clinical significance of early thrombosis after prosthetic mitral valve replacement: a postoperative monocentric study of 680 patients.

OBJECTIVES: The aim of this study was to evaluate the incidence of early thrombosis, its prognostic significance, and the therapeutic implications. BACKGROUND: Transesophageal echocardiography (TEE) is the method of choice for detecting symptomless early postoperative thrombosis of prosthetic valves. However, the clinical significance is not yet known. METHODS: Between June 1994 and December 2000, 680 consecutive patients underwent TEE on day 9 after mechanical mitral valve replacement, to search for early thrombosis. Initially, end points were the in-hospital outcome and treatment. Patients were also evaluated 34 +/- 22 months after surgery. RESULTS: Sixty-four early thrombi were detected (9.4%). Two early obstructive were treated by redo-surgery. Sixty-two nonobstructive benefited from medical treatment. The patients were allocated into two groups as a function of the maximum size of thrombus: <5 mm in 29 patients (group A) and > or =5 mm in 35 (group B). During early follow-up, we observed one complicated course in group A and eight in group B. In the long-term survey, three complications were noted in group A and 11 in group B. Incidence of early (p = 0.027) and long-term (p = 0.04) complications were significantly different in the two subsets. CONCLUSIONS: This study confirms the incidence of early thrombi after mechanical mitral valve replacement detected by TEE. A small (<5 mm) nonobstructive thrombus seems benign, and our experience argues in favor of medical treatment. Prognosis appears more serious for large thrombi. Medically aggressive therapy and further surgery should be considered in cases of obstructive thrombosis or large and mobile nonobstructive thrombosis.

Surgical ablation of atrial fibrillation with off-pump, epicardial, high-intensity focused ultrasound: results of a multicenter trial.

BACKGROUND: A simplified alternative to the Cox maze procedure to treat atrial fibrillation with epicardial high-intensity focused ultrasound was evaluated clinically, and the initial clinical results were assessed at the 6-month follow-up visit. METHODS: From September 2002 through February 2004, 103 patients were prospectively enrolled in a multicenter study. Atrial fibrillation duration ranged from 6 to 240 months (mean, 44 months) and was permanent in 76 (74%) patients, paroxysmal in 22 (21%) patients, and persistent in 5 (5%) patients. All patients had concomitant operations, and ablation was performed epicardially on the beating heart before the concomitant procedure. The device automatically created a circumferential left atrial ablation around the pulmonary veins in an average of 10 minutes, and an additional mitral line was created epicardially in 35 (34%) patients with a handheld device by using the same technology. RESULTS: No complications or deaths were device or procedure related. There were 4 (3.8%) early deaths and 2 late extracardiac deaths. The 6-month follow-up was complete in all survivors. At the 6-month visit, freedom from atrial fibrillation was 85% in the entire study group (80% in patients with permanent atrial fibrillation, 88% in the 35 patients who had the additional mitral line, and 100% in patients with paroxysmal atrial fibrillation). A pacemaker was implanted in 8 patients. Only the duration and type of atrial fibrillation significantly increased the risk of recurrence. CONCLUSION: Epicardial, off-pump, beating-heart ablation with acoustic energy is safe and cures 80% of patients with permanent atrial fibrillation associated with long-standing structural heart disease.

Prospective study of hemodynamic performances of standard ATS and AP-ATS valves.

BACKGROUND AND AIM OF THE STUDY: Following aortic valve replacement (AVR), a residual transprosthetic gradient can develop which has detrimental long-term effects, especially with regard to left ventricular mass regression and subsequent mortality. The Advanced Performance-ATS valve (AP-ATS) was developed to overcome this potential patient-prosthesis mismatch. In the present study, the early postoperative transprosthetic gradient was determined after AVR with ATS valves 18 to 25, to confirm the promise of superior hemodynamic performance of the AP series and to define respective indications. METHODS: This prospective study included 302 consecutive patients operated on for AVR between December 1997 and December 2000. In all patients, body surface area (BSA), associated with mean transprosthetic gradient and paravalvular leaks (measured echocardiographically) was monitored, between the 5th and 8th postoperative days. RESULTS: A significantly lower mean transprosthetic gradient was found for size 22 and 24 valves, compared with size 23 and 25 valves. Results for size 18 and 20 valves were in concordance with those obtained for size 22 and 24 valves. For size 23 valves the mean gradient was significantly higher when the BSA was >1.9 m2, but the use of size 22 valves in these patients overcame this potential patient-prosthesis mismatch. No patient was reoperated on for paravalvular leakage, and no greater degree of paravalvular leakage was found with AP-ATS than with Standard ATS valves. CONCLUSION: These results confirm the global good hemodynamic performances of Standard ATS and especially of the AP-ATS valves. However, the significantly lower mean gradient found in the AP-ATS valves recommends their use in patients with larger BSA.

Frizzled A, a novel angiogenic factor: promises for cardiac repair.

OBJECTIVE: Frizzled A is a very recent protein expressed in the cardiovascular hood by cardiomyocytes and by endothelial cells. This protein plays key roles in vitro in vascular cell proliferation and is able to induce an in vivo angiogenic response. Regarding these properties, we assess the hypothesis that Frizzled A could act in the healing process after myocardial infarction. METHODS: To investigate the role of Frizzled A, we established a transgenic mouse line overexpressing the protein and developed a model of myocardial infarction by coronary artery ligation. RESULTS: The incidence of cardiac rupture after myocardial infarction was reduced in transgenic mice (6.5 versus 26.4% in controls, n=165; P<0.01). Infarct sizes were smaller in transgenic mice (18% of left ventricle circumference versus 28.1% in control at day 30; P<0.001; n=6) and the cardiac function was improved (3800 +/- 370 versus 2800 +/- 840 mmHg/s dp/dtmax in controls, -2800 +/- 440 versus -1800 +/- 211 dp/dtmin in controls at day 15; P<0.001; n=6). Early leukocyte infiltration had decreased in transgenic mice during the first week (103 +/- 59 versus 730 +/- 463 cells/mm2 in controls at day 7; P<0.001; n=6) and the apoptotic index was decreased by 50% at day 7. Capillary density in the scar was higher in transgenic mice (290 +/- 103 versus 104 +/- 43 vessels/mm2 in control at day 15; P<0.001) and vessels were more muscularized and mean lumen area was 3-fold higher (952 +/- 902 versus 313 +/- 350 microm2 in control; P<0.001). CONCLUSION: Overexpression of Frizzled A reduced the infarct size, improved cardiac recovery, modified inflammatory response and amplified angiogenesis. For these reasons, this protein would be of interest for cardiac surgeons using angiogenic therapy (as gene or protein injection) in ischemic heart diseases in non-revascularizable patients.

Surgery for prosthetic valve obstruction. A single center study of 136 patients.

OBJECTIVES: Prosthetic heart valve obstruction (PHVO) is a potentially fatal complication of heart valve replacement with mechanical substitute mainly due to thrombosis. The purpose of this report is to present a single-center experience of 136 consecutive patients operated on between 1978 and 2001. METHODS: The diagnosis of PHVO was mainly assessed by fluoroscopy and/or echocardiography. Thrombosed valves were bileaflet (82), tilting disc (47) and ball cage (7) valves; of these, 90 were in mitral, 38 in aortic, six in aortic and mitral position, and two in tricuspid position. The mean interval between the first implantation and valve thrombosis was 7.4+/-6.6 years (range 1 day to 28 years); in 37 patients preoperative medical therapy (fibrinolysis in 21, and heparin alone in 16) was unsuccessful. RESULTS: Operative procedures included valve re-replacement in 104 cases and declotting-pannus excision in 32 cases. Early hospital mortality was 10.3% (14 patients), all in NYHA class III or IV, and one patient suffered a perioperative cerebral embolic event. Surgery was then successful in 121 of 136 patients (89%), but during a 3.15-year follow-up, prosthetic heart valve thrombosis recurred in ten out of 122 survivors (8.1%). CONCLUSION: From this experience, it can be concluded that for most PHVO, early operation is currently effective and safe, especially in patients in stable hemodynamic condition preoperatively.

[Study of postmyocardial infarction scar-formation mechanisms: advantage of an experimental myocardial infarction model in mice]. / Etude des mécanismes de cicatrisation après infarctus du myocarde: intérêt d'un modèle expérimental d'infarctus du myocarde chez la souris.

Myocardial infarction involves scar-formation mechanisms in which inflammation, proliferation, cell differentiation, apoptosis and angiogenesis all play a role. Better knowledge of the scar-formation process would be helpful in developing new therapies. The authors have generated a mouse model for infarction because its possible application in transgenic mice would allow the role of target genes in postinfarction scar-formation mechanisms to be studied. An infarction is caused by ligating the descending branch of the left coronary artery. At various times after ligation, the mice are sacrificed to determine the size of the infarction, left ventricular function and the overall myocardial scar-formation process. Early mortality was 10%. Between the fourth and sixth day postsurgery, 25% of mice died of a ruptured, infarcted left ventricle. The size of the infarctions diminished with time, while the surface of the left ventricle increased. In hemodynamics, 15 and 30 days after infarction, left ventricle telediastolic pressure was higher, telesystolic pressure was lower and contractility in indexes had collapsed. After an inflammatory phase in which polynuclear neutrophils colonized the scar, granulation tissue set in with a proliferation of myofibroblasts and growth of new blood vessels. These cells disappeared from the scar gradually, leaving behind a matrix rich in collagen and devoid of any contractile properties. The authors have characterized a murine model of myocardial infarction, with applications in transgenic mice and in view of establishing new agents in postmyocardial infarction repair.

Management of Nonobstructive Thrombosis of Prosthetic Mitral Valve in Asymptomatic Patients in the Early Postoperative Period: A Study in 20 Patients.

The purpose of the present study was to determine the optimal management of nonobstructive thrombi in the early postoperative period after mitral valve replacement.Twenty cases of early thrombi were revealed by systematic transesophageal echocardiography (TEE) performed 9 days after surgical implantation of 229 St. Jude prostheses. Patients were prospectively randomized into two groups: the first group received oral anticoagulants (fluindione), and the second group was treated with a combination of oral anticoagulants and aspirin. The impact of the different therapies on prosthetic thrombi was assessed by systematic TEE at 5 months. All thrombi were nonobstructive and disappeared without fibrinolytic agents or surgery. Seven large (>/= 5 mm) thrombi disappeared: in two patients after reintroduction of intravenous heparin and in five patients with an optimized oral treatment (anticoagulants alone in one patient, anticoagulants associated with aspirin in four patients). In the 13 small (< 5 mm) thrombi, 11 disappeared with an optimized oral treatment: anticoagulants alone in nine patients and anticoagulants associated with aspirin in two patients. The other two small thrombi treated with heparin alone initially persisted and finally disappeared with heparin associated with aspirin. In the group with large thrombi, we recorded a 43% rate of thromboembolic events, with more deaths and severe cerebral embolic events than in the patients with small thrombi. Embolic events were associated with mobile thrombi. An optimized oral anticoagulation therapy with correction of the parameters of Virchow et al. is effective in the treatment of small prosthetic thrombi. For large thrombi, the high rate of thromboembolic events would appear to require a more aggressive approach such as an association of heparin with aspirin and TEE follow-up.

Proposed modification for valve-sparing aortic root replacement.

Valve-sparing aortic root replacement (ARR) is the procedure of choice in young patients with aortic root aneurysm and preserved aortic valve leaflets; however, coronary ostial anastomoses remain an issue. Troublesome bleeding sometimes occurs during surgery, and in the long term, there is a risk of aneurysmal formation in the residual aortic wall of the ostial "button." We describe a technique of valve-sparing ARR wherein each coronary button along with its flange of aortic tissue is implanted within the prosthetic graft used for ARR, thereby eliminating the risk of both immediate surgical bleeding and late coronary button aneurysms.

Management of prosthetic heart valve obstruction: fibrinolysis versus surgery. Early results and long-term follow-up in a single-centre study of 263 cases.

Optimal management of prosthetic heart valve obstruction (PHVO) remains controversial even though surgery is usually recommended. To better define the efficacy and safety of fibrinolysis versus surgery in the pre- and post-transoesophageal echocardiography (TEE) eras. We analysed initial results and follow-up data from a large, retrospective, single-centre series, comparing fibrinolysis and surgery in patients with PHVO treated over 20 years. Two hundred and sixty-three consecutive episodes of PHVO in 210 patients, mainly left sided, were managed in our institution by either fibrinolysis (n=127) or surgery (n=136). Early clinical evolution was assessed in terms of haemodynamic success and complications. Concerning early results, there were no significant differences between the two groups in terms of mortality (10%). However, haemodynamic success was significantly more frequent in the surgical group (89% versus 70.9% p<0.001), embolic episodes were significantly more frequent in the fibrinolysis group (15% versus 0.7%, p<0.001), as were total complications (25.2% versus 11.1%, p=0.005). Long-term follow-up, with a mean duration of 6 years (range: 0-20), was obtained and showed significantly better results in the surgical group in terms of recurrence (p=0.021) and mortality (p=0.002). In univariate and multivariable analyses, NYHA functional class at presentation was a strong predictor of late death (p<0.01). Management of patients during the pre- and post-TEE eras was significantly different, since introduction of TEE surgery has become the preferred therapeutic strategy. Results of this extensive single-centre experience indicate that since the introduction of TEE, surgery is more frequently performed than fibrinolysis due to the improvement of thromboembolic risk assessment. Furthermore, prompt surgical treatment is associated with a better early success rate and a significantly lower incidence of complications than fibrinolysis in left-sided PHVO. However, fibrinolysis may be justified in selected cases. Long-term follow-up showed significantly better results in the surgical group in terms of recurrence and mortality.

Right coronary sinus fixation through a right ventriculotomy for David's procedure.

A key element to the success of aortic valve reimplantation (David's procedure) is the position of the aortic annulus in the Dacron tube (DuPont, Wilmington, DE). The variable level of the right ventricular insertion can cause technical difficulties, especially when the right ventricular insertion occurs above the aortic annulus. To resolve this issue, a technical adjunct is described using a right superior ventriculotomy. This technique allows perfect aortic annulus containment, avoids any rocking motion of the margin of the right coronary cusp, and affords the procedure better long-term durability.

Experimental validation of circumferential, longitudinal, and radial 2-dimensional strain during dobutamine stress echocardiography in ischemic conditions.

OBJECTIVES: The aim of this study was to assess and validate 2-dimensional (2D) strain for the detection of ischemia during dobutamine stress echocardiography (DSE). BACKGROUND: Evaluation of abnormalities of left ventricular (LV) function from wall thickening during DSE is unsatisfactory and requires a high level of expertise. METHODS: In 10 open-chest anesthetized pigs, myocardial deformation was studied before and during dobutamine infusion, under control and ischemic conditions produced by various degrees of coronary artery constriction: 2 of nonflow-limiting stenoses (NFLS) of increasing severity reducing left anterior descending artery hyperemic flow by 40% and 70% and 2 flow-limiting stenoses (FLS) reducing resting coronary flow by 25% and 50%. Agreement between 2D strain echocardiography and sonomicrometry (reference method) was evaluated by linear regression and Bland-Altman analysis. RESULTS: Good correlation and agreement were observed between 2-dimensional strain and sonomicrometry at rest and during dobutamine infusion; longitudinal strain: r = 0.77, p < 0.001 and r = 0.80, p < 0.001; radial strain: r = 0.57, p < 0.05 and r = 0.63, p < 0.05; and circumferential strain: r = 0.74, p < 0.001 and r = 0.58, p < 0.001. Circumferential and longitudinal strains in the risk area were significantly decreased at rest in the presence of FLS and during dobutamine infusion in the presence of NFLS. By contrast, radial strain was significantly decreased in the presence of severe FLS only during dobutamine infusion. CONCLUSIONS: The 2D strain provides accurate assessment of LV regional function. Evaluation of circumferential and longitudinal strains during DSE has real potential for quantitative evaluation of LV deformation in the routine assessment of ischemia.

Endovascular treatment of a tuberculous infected aneurysm of the descending thoracic aorta: a word of caution.

An infected aneurysm of the thoracic aorta due to mycobacterium tuberculosis is an unusual entity for which the classical treatment is antituberculosis chemotherapy and open-chest surgery. Recent improvements in endovascular treatments have led to their proposed use for infected aneurysms in patients for whom open surgery poses too high a risk. We report on a 68-year-old man with a tuberculous aortic aneurysm who had been treated with an endoprosthesis and antituberculosis chemotherapy. His clinical and radiological follow-up was uneventful and led to the discontinuation of pharmacological treatment after 16 months. However, a recurrence of the infection led to a fatal aortic rupture 4 months after discontinuation of therapy.

'Double patch and glue' technique for early repair of posterior post-infarction ventricular septal defect.

A surgical procedure that reduces the recurrence of post-infarction posterior ventricular septal defects is described. This technique is based on a double ventriculotomy without an infarctectomy, the use of two patches, and glue, which is applied between the two patches. Excellent results have been obtained in 18 consecutives patients with this simple and reliable technique.

Surgery for post-infarction ventricular septal defect (VSD): double patch and glue technique for early repair.

Repair of post-infarction ventricular septal defect (VSD) remains a challenging procedure with a high risk of VSD recurrence. In order to reduce this risk, a double patch and glue technique was introduced in the department in 1986. This surgical technique is hereunder presented. Since 1971, ninety-three patients have been operated on early (≪15 days) after the occurrence of a post-infarction VSD. This retrospective study allows to compare the results of this double patch and glue technique to those obtained with the conventional one, in terms of hospital death and VSD recurrence. The double patch and glue technique avoids recurrence of VSD and plays a part in reducing hospital mortality.

Gene therapy for chronic peripheral arterial disease: what role for the vascular surgeon?

The incidence of peripheral arterial disease is rising and despite advances in clinical management, many problems remain unsolved. Better knowledge of the mechanisms and consequences associated with chronic muscle ischemia has opened the way for development of new treatment strategies, including therapeutic angiogenesis. Therapeutic angiogenesis is a promising technique based on experimental studies showing that growth factors or genes able to increase capillary density can be used to reduce the impact of muscle ischemia and increase blood flow to ischemic tissue. Enthusiasm for this technique has prompted numerous clinical trials with encouraging results, but data are still inconclusive. Optimal indications for gene therapy must be defined and further experimental progress is needed to respond to ethical issues. Therapeutic angiogenesis should be viewed as an adjunct to rather than as a competitor of current surgical revascularization techniques.

Repair of myocardial infarction by epicardial deposition of bone-marrow-cell-coated muscle patch in a murine model.

BACKGROUND: Myocardial infarction results in irreversible myocyte loss. In a murine model, we tested the feasibility of a novel repair technique combining bone marrow cell (BMC) transplantation and cardiomyoplasty. METHODS: Myocardial infarction was induced cryogenically in backcrossed ROSA 26 transgenic x C57BL/6J mice (n = 75). Thirty days later, surviving mice (n = 69) were randomized to sham treatment (rethoracotomy only; n = 11), patch only treatment (n = 29), or patch + BMC treatment (n = 29). Abdominal muscle patches were harvested from donor littermates not expressing the beta-galactosidase reporter gene and sutured on the epicardium directly above the infarct zone. Patch only-treated mice received uncoated patches. Patch + BMC-treated mice received patches coated with 5 x 10(6) beta-galactosidase-expressing BMCs embedded in a collagen-rich three-dimensional matrix. RESULTS: Mortality rate was 52% after muscle patch implantation. Bone marrow cells were able to migrate from muscle patch into the infarct zone, as demonstrated by beta-galactosidase immunostaining, and ultimately constituted 8% of all cells in scar tissue (mean +/- standard deviation, 219 +/- 111/mm2). Angiogenesis and cell survival in the scar were improved by patch + BMC treatment. Left ventricular geometry and cardiac function were improved by patch treatment, with or without BMC, although the effects were stronger after patch + BMC treatment. CONCLUSIONS: Epicardial deposition of a BMC-coated muscle patch is a promising approach to restoring cardiac function after myocardial infarction.