Paul Achouh

Carbon monoxide induces relaxation of human internal thoracic and radial arterial grafts

Carbon monoxide is produced by the degradation of heme by intracellular heme-oxygenase. The aim of our study was to evaluate, in vitro, the vasodilating effect of carbon monoxide and its mechanisms of action on human internal thoracic and radial artery grafts. Segments of human internal thoracic artery and radial artery, obtained from isolated coronary artery bypass surgery patients, were studied in organ chambers. The arterial rings were precontracted with norepinephrine then submitted to carbon monoxide. Inhibitors of nitric oxide synthase and of soluble guanylate cyclase were added to some arterial rings. Carbon monoxide induced significant relaxation in precontracted human internal thoracic artery and radial artery rings. This relaxation was independent of the presence of functional endothelium in internal thoracic artery. Blocking soluble guanylate cyclase partially inhibited this relaxation, while blocking nitric oxide synthase had no effect. Carbon monoxide has a relaxing effect on human internal thoracic artery and radial artery grafts in vitro, partially via cyclic guanylate monophosphate (cGMP) pathway activation. Inducing carbon monoxide production at the cellular level in vivo in human arterial grafts might help prevent vasospasm.

Endoluminal Gingival Fibroblast Transfer Reduces the Size of Rabbit Carotid Aneurisms via Elastin Repair

Objective—Matrix metalloproteinase-9 is considered to play a pivotal role in aneurismal formation. We showed that gingival fibroblasts (GF) in vitro reduced matrix metalloproteinase-9 activity via increased secretion of tissue inhibitor of metalloproteinase 1. We aimed to evaluate in vivo the efficacy of GF transplantation to reduce aneurism development in a rabbit model. Methods and Results—Seventy rabbit carotid aneurisms were induced by elastase infusion. Four weeks later, GF, dermal fibroblast, or culture medium (DMEM) were infused into established aneurisms. Viable GF were abundantly detected in the transplanted arteries 3 months after seeding. GF engraftment resulted in a significant reduction of carotid aneurisms (decrease of 23.3% [P<0.001] and 17.6% [P=0.01] of vessel diameter in GF-treated arteries, 1 and 3 months after cell therapy, respectively), whereas vessel diameter of control DMEM and dermal fibroblast–treated arteries increased. GF inhibited matrix metalloproteinase-9 activity by tissue inhibitor of metalloproteinase 1 overexpression and matrix metalloproteinase-9/tissue inhibitor of metalloproteinase 1 complex formation, induced elastin repair, and increased elastin density in the media compared with DMEM-treated arteries (38.2 versus 18.0%; P=0.02). Elastin network GF-induced repair was inhibited by tissue inhibitor of metalloproteinase 1 blocking peptide. Conclusion—Our results demonstrate that GF transplantation results in significant aneurism reduction and elastin repair. This strategy may be attractive because GF are accessible and remain viable within the grafted tissue.

Mediastinitis due to Gram-negative bacteria is associated with increased mortality

The aim of this study was to describe the features of a large cohort of patients with postoperative mediastinitis, with particular regard to Gram-negative bacteria (GNB), and assess their outcome. This bicentric retrospective cohort included all patients who were hospitalized in the Intensive Care Unit with mediastinitis after cardiac surgery during a 9-year period. Three hundred and nine patients developed a mediastinitis with a mean age of 65 years and a mean standard Euroscore of six points. Ninety-one patients (29.4%) developed a GNB mediastinitis (GNBm). Of the 364 pathogens involved, 103 GNB were identified. GNBm were more frequently polymicrobial (44% versus 3.2%; p <0.001). Being female was the sole independent risk factor of GNBm in multivariate analysis. Initial antimicrobial therapy was significantly more frequently inappropriate with GNBm compared with other microorganisms (24.6% versus 1.9%; p <0.001). Independent risk factors for inappropriateness of initial antimicrobial treatment were GNBm (OR = 8.58, 95%CI 2.53-29.02, p 0.0006), and polymicrobial mediastinitis (OR = 4.52, 95%CI 1.68-12.12, p 0.0028). GNBm were associated with more drainage failure, secondary infection, need for prolonged mechanical ventilation and/or use of vasopressors. Thirty-day hospital mortality was significantly higher with GNBm (31.9 % versus 17.0%; p 0.004). GNBm was identified as an independent risk factor of hospital mortality (OR = 2.31, 95%CI 1.16-4.61, p 0.0179).

Cost-Effectiveness of Mitral Valve Repair Versus Replacement by Biologic or Mechanical Prosthesis

BACKGROUND Surgical treatment strategies for mitral valve disease have progressively shifted toward repair given the better survival outcomes with this type of intervention. However, valve repairs and valve replacement may require reoperations with time. In the absence of clinical trials assessing the effectiveness of various mitral surgical treatments with time, we propose to develop cost-effectiveness models to compare sequential treatment strategies. METHODS Three simulation models were carried out to assess the cost-effectiveness of mitral valve repair as first-line treatment, compared with either mechanical or biologic valve replacements. Efficacy data were derived from both the published literature and from a specific clinical cohort of 582 patients treated for this condition. Using the French public health care system perspective, relevant direct costs were derived using a local resource utilization assessment and official costing data sources. RESULTS Over 10 years, costs per success were significantly lower (p < 0.01) for the mitral valve repair strategy versus biologic or mechanical valve replacements (€35,550, €49,492, and €54,634 per success, respectively). Over 20 years, costs per success were significantly lower (p < 0.01) for the mechanical valve replacement strategy compared with the mitral valve repair and biologic valve replacement (€94,763, €100,053, and €147,484 per success, respectively). CONCLUSIONS Considering the increased referral rate in older patients with degenerative mitral valve disease, and their shorter life expectancy, these results show that when medically required and technically practicable, mitral valve repair should be considered as the first-line strategy.

Deep hypothermia and low flow for surgery for abdominal or extraperitoneal tumors with cavoatrial extension.

BACKGROUND Surgical treatment of retroperitoneal tumors with cavoatrial involvement can be challenging. Completeness of resection of the cava tumor extension is crucial for the patients survival. We report a monocentric experience with the use of cardiopulmonary bypass and deep hypothermic low flow for the surgical resection of caval and atrial involvement of retroperitoneal tumors. METHODS Between 2006 and 2011, 9 patients were admitted in our cardiovascular surgery department for retroperitoneal tumors with cavoatrial extension. Every case was performed with cardiopulmonary bypass under deep hypothermia (18°C) with a continuous low-flow perfusion (1 to 1.5 L/min). Cardiopulmonary bypass output was tuned to obtain a nearly bloodless field. Reconstruction of the atriohepatic confluent was carried out with a pericardium patch without inferior vena cava reconstruction. RESULTS There was no perioperative death. Mean duration of deep hypothermic low flow was 52.2 ± 18.2 minutes. The lowest mean esophageal temperature obtained during procedure was 18.2° ± 1.4°C. No neurologic event was noted postoperatively. Three patients had early complications: one reintervention for bleeding, one reintervention for mediastinitis, and one transient moderate renal failure. After a year, all patients were alive with patent atriohepatic reconstruction. CONCLUSIONS Cardiopulmonary bypass with deep hypothermic low flow facilitates tumor resection and reconstruction of the atriohepatic confluent. It provides satisfactory postoperative results. It should be considered as an option in the management of these retroperitoneal tumors with cavoatrial involvement.

Aortic Biological Valve Thrombosis in an HIV Positive Patient

Biological aortic valve thrombosis is an exceptional complication. A 64-year-old patient positive for human immunodeficiency virus presented for syncope on exertion, 2 years after an aortic bioprosthetic valve replacement and double coronary artery bypass. Transvalvular aortic mean gradient was approximately 50 mm Hg on echocardiogram and catheterization. Cardiac computed tomography scan showed a limited opening of the bioprosthesis cusps. Surgical exploration revealed thrombosis of the three cusps on the aortic side, limiting the opening of the valve. No relation could be established between the patients human immunodeficiency virus status and valve thrombosis.

Giant right coronary pseudo-aneurysm 6 years after angioplasty and stenting

An asymptomatic 73-year-old male was referred for descending thoracic aortic aneurysm. He had a history of uneventful triple bare-metal stenting of the right coronary artery 6 years earlier. Echocardiography and cardiac computed tomography (CT) revealed a 3 cm 3 cm right coronary artery pseudoaneurysm (Fig. 1) that was treated surgically (Fig. 2). www.elsevier.com/locate/ejcts European Journal of Cardio-thoracic Surgery 37 (2010) 1227

New insights on tuberculous aortitis

Objective: Aortitis is an exceedingly rare manifestation of tuberculosis. We describe 11 patients with tuberculous aortitis (TA). Methods: Multicenter medical charts of patients hospitalized between 2003 and 2015 with TA in Paris, France, were reviewed. Demographic, medical history, laboratory, imaging, pathologic findings, treatment, and follow‐up data were extracted from medical records. TA was considered when aortitis was diagnosed in a patient with active tuberculosis. Results: Eleven patients (8 women; median age, 44.6 years) with TA were identified during this 12‐year period. No patient had human immunodeficiency virus infection. Tuberculosis was active in all cases, with a median delay of 18 months between the first symptoms and diagnosis. At disease onset, vascular signs were mainly claudication, asymmetric blood pressure, and diminished distal pulses. Constitutional symptoms or extravascular signs were present in all patients at some point. Aortic pseudoaneurysm was the most frequent lesion, but three patients had isolated inflammatory aortic stenosis. TA appeared as extension from a contiguous infection in only three cases. Tuberculosis was considered because of clinical features, tuberculin skin or QuantiFERON‐TB Gold (Quest Diagnostics, Madison, NJ) test results, pathologic findings, and improvement on antituberculosis therapy. A definite Mycobacterium tuberculosis identification was made in only three cases. All patients received antituberculosis therapy for 6 to 12 months. Surgery including Bentall procedures, aortic bypass, and open abdominal aneurysm repair was performed at diagnosis in eight patients. Seven patients received steroids as an adjunct therapy. All patients clinically improved under treatment. No patients died for a median follow‐up duration of 4 years. Conclusions: TA may result in aneurysms contiguous to regional adenitis but also in isolated inflammatory aortic stenosis. Steroids may be associated with antituberculosis therapy for inflammatory stenotic lesions. Surgery is indicated for aneurysms and in case of worsening stenotic lesions despite anti‐inflammatory drugs. No patient died after such combined treatment strategy.

Advanced Mitral-Tricuspid Disease With Severe Right Ventricular Dysfunction: The Double-Staged Approach

Tricuspid valve surgery in the presence of severe right ventricular dysfunction and pulmonary hypertension secondary to mitral valve stenosis is associated with poor early outcomes. We report the case of a young patient, presenting with severe chronic mitral-tricuspid disease responsible for long-lasting pulmonary hypertension and altered right ventricular function, who initially underwent mitral valve replacement and 7 days later the correction of her tricuspid insufficiency. This 2-staged approach permitted progressive reduction of pulmonary pressure and partial right ventricular remodeling before closing the systolic release valve of the right ventricle represented by tricuspid regurgitation.

Improved Survival After Implementation of a Large-Scale Regional Dedicated Aortic Network

Acute aortic diseases (AADs) include mainly abdominal or thoracic aortic aneurysms and acute aortic syndromes. Referring patients with AAD to specialized centers is particularly relevant considering the well-established volume–outcome relationship for cardiovascular surgery [(1)][1]. A regional