Jorge Sierra

Aorto-enteric fistula is a serious complication to aortic surgery. Modern trends in diagnosis and therapy.

Secondary aorto-enteric fistula (AEF) is a serious, but rare, complication following surgery of the abdominal aorta. AEF occurs in 0.3-2%, but is associated with a hospital mortality between 25-90%. It is also associated with an important morbidity with a lower limb amputation rate of 9%, and a 15% risk for renewed graft infection. Nine secondary AEF were surgically treated. The hospital mortality was high,44% (4/9). Recurrent AEF was observed in 1 patient 2 years after the first operation. During follow-up 2 patients had mild infections which were resolved by antibiotic treatment. Diagnostic modalities, and recent advancements in surgical treatment as well as preventive measures are discussed.

Midterm results of valve repair with a biodegradable annuloplasty ring for acute endocarditis.

BACKGROUND Conventional annuloplasty rings consist of woven, nondegradable prosthetic material. Their use should theoretically be limited in acute infective endocarditis. Novel biodegradable annuloplasty rings, which are implanted into the annulus, carry theoretical advantages, but have never been evaluated for feasibility and mid-term outcome in such patients. METHODS Between 2004 and 2009, 17 consecutive patients with acute infective endocarditis (age, 34.5+/-21.6 years; range, 11-82 years; 8 men) had mitral (n=13), tricuspid (n=3), and mitral and tricuspid (n=1) annuloplasty to conclude valve repair. Repair was performed by complete excision of the infected tissue, valvar reconstruction, and biodegradable ring annuloplasty. Prospectively collected clinical and echocardiographic data were analyzed retrospectively. RESULTS Indications for surgery were heart failure (n=9; 52.9%), hemodynamic instability (n=8; 47%), and persistent infection or sepsis despite antibiotics (n=6; 35.3%). Staphylococci (n=7) and Streptococci (n=4) were the most common causes. Three patients died on postoperative days 1, 2, and 34 because of massive gastrointestinal bleeding; heart failure and pneumonia; and sepsis and acute renal failure, respectively. During a median follow-up of survivors at 29.6 months (range, 2.0 to 51.0 months), no mortality, recurrence, or reoperation occurred. At follow-up, transthoracic echocardiography revealed no or trivial regurgitation in 11 and mild in 3 patients. Left ventricular dimensions regressed significantly after mitral repair. CONCLUSIONS Valve repair using a biodegradable ring showed good structural and functional properties up to 4 years after repair. Implantation of the biodegradable ring is feasible and effective in patients with acute infective endocarditis. Its intraannular implantation, hindering direct blood contact and associated risk of colonization, represents a theoretical advantage in such patients. Larger comparative studies are needed for further conclusions.

Cardiovascular response to acute normovolaemic haemodilution in patients with severe aortic stenosis: assessment with transoesophageal echocardiography

Using multiplane transoesophageal echocardiography (TOE), we investigated the haemodynamic response to acute normovolaemic haemodilution (ANH) in anaesthetised patients with critical aortic stenosis. Twenty‐eight patients were randomly assigned to ANH or control groups. In the control group, haemodynamic data remained unchanged over a 20‐min period. In the ANH group, haemoglobin levels decreased from a mean (SD) of 134 (7) to 91 (9) g.l−1 (p < 0.001) whereas stroke volume, central venous pressure and left ventricular (LV) end‐diastolic area all increased significantly (mean (SD) +15 (6) ml; +2.0 (1.1) mmHg; +2.1 (0.8) cm2, respectively). During ANH, the accelerated blood flow through the stenotic valve caused an increased loss (SD) in LV stroke work: from 24 (8)% to 30 (10)%), (p < 0.01). Hence, lowering viscosity with ANH resulted in improved venous return, higher cardiac preload and increased stroke volume. However, this adaptive haemodynamic response was limited by less efficient LV stroke work due to dissipation of fluid kinetic energy.

Continuous haemodynamic monitoring using transoesophageal Doppler during acute normovolaemic haemodilution in patients with coronary artery disease

Transoesophageal Doppler monitoring allows non‐invasive assessment of stroke volume. We studied haemodynamic changes during acute normovolemic haemodilution (ANH) in anaesthetised patients with coronary artery disease. Twenty patients were randomly assigned to either ANH or a control group. During ANH, a mean (SD) blood volume of 15.3 (3.4) ml.kg−1 was withdrawn decreasing systemic oxygen delivery from 12.7 (3.3) to 9.3 (1.8) ml.kg−1.min−1 (p < 0.001). In the control group, haemodynamic data remained unchanged, whereas in the ANH group, stroke volume and central venous pressure increased significantly (mean = +21 ml [95% CI: 18–25 ml.min−1]; mean = +2.5 mmHg [95% CI: 2.2–2.8 mmHg], respectively) and heart rate decreased (mean = −6 beat.min−1[95% CI: 6–8 beat.min−1], p < 0.05). According to the Frank–Starling relationship, individual changes in stroke volume compared with central venous pressure fitted a quadratic regression model (R2 > 0.91). A reduced viscosity associated with ANH resulted in improved venous return, higher cardiac preload and increased cardiac output. In summary, this study demonstrated that ANH to a haemoglobin value of 8.6 g.dl−1 was well tolerated in patients with coronary artery disease.

Repair of aortic coarctation using temporary ascending to descending aortic bypass in children with poor collateral circulation.

Aortic coarctation can now be repaired surgically with excellent results. Even though rare, injury to the spinal cord resulting in paraplegia remains a major concern. Preoperative evaluation showing the absence of collateral circulation is valuable in order to introduce protective actions. This report describes our experience using a temporary bypass from the ascending to the descending aorta bypass in children undergoing surgical correction of aortic coarctation in the setting of poorly developed collateral circulation. Between 1990 and 2002, we undertook direct surgical repair in 56 patients with isolated aortic coarctation, 20 as neonates, 11 as infants, and 25 during childhood. From 1998 onwards, we introduced preoperative evaluation of the collateral circulation with magnetic resonance imaging. From that time, we placed a temporary bypass from the ascending to the descending aorta, using a polytetrafluoroethylene tube of 4 to 8 mm diameter, whenever distal pressures were shown to be 25 mmHg or less after test clamping, or when magnetic resonance imaging revealed absence of collateral circulation. We found excellent correlations between the direct intra-operative measurements of distal pressure and the findings at magnetic resonance imaging. Following introduction of the temporary bypass, we observed no neurological complications, nor were there any complications related to bypass. Freedom from restenosis was 96%. Preoperative magnetic resonance imaging, therefore, can accurately visualize poor collateral circulation in children with aortic coarctation. The use of a temporary bypass can possibly eliminate the risk of neurological sequels following direct repair of coarctation in children with poorly developed collateral circulation. The temporary bypass is both easy to apply and safe.

Drainage of the inferior vena cava to the left atrium.

Drainage of the inferior vena cava to the left atrium is an extremely unusual congenital heart disease. We describe a 54‐year‐old woman, in whom the diagnosis was suggested by transthoracic echocardiography, and then confirmed by a transesophageal exam and magnetic resonance imaging, which also revealed an associated secundum atrial septal defect. Surgical management involved reconstruction of the interatrial septum to include the inferior vena cava in the right atrium. The few previously reported cases in the literature are reviewed. (ECHOCARDIOGRAPHY, Volume 20, February 2003)

Long Intraaortic Balloon Treatment Time Leads to More Vascular Complications

Intraaortic balloon counterpulsation is an established and efficient therapy. Limb ischemia is the most common complication. The impact of treatment duration on balloon-related complications was analyzed retrospectively in 135 patients who underwent balloon counterpulsation between 1998 and 2004. Thirty high-risk coronary patients required preoperative intraaortic balloon therapy, 41 were in preoperative cardiogenic shock, and 64 needed support for difficulties in weaning from cardiopulmonary bypass. No balloon-related mortality occurred. The overall balloon-related complication rate was 20/135 (14.8%); 18 had limb ischemia, of whom 6 (4.4%) required vascular interventions. Intraaortic balloon treatment time was significantly longer in patients who developed limb ischemia (99.8 ± 54.1 h) compared to those who did not (34.4 ± 30.4 h). Preoperative therapy had short treatment times and few complications. Intraaortic balloon pumping provides effective circulatory support with a low complication rate. A clear relationship was established between duration of treatment and balloon-related complications. Independent risk factors for balloon-related complications were long treatment time, acute myocardial infarction, age over 65 years, and ejection fraction less than 0.30.

Mycotic aneurysm of the superior mesenteric artery

A 47-year-old man without any significant medical history was admitted with a high fever (398C). On admission, his white blood cell count was normal (5.1 g/L), his C-reactive protein level was 18 mg/L, and the rest of blood test was within the normal range. He had no abdominal complaints, and the physical examination was unremarkable save for a diastolic heart murmur. The blood culture revealed Streptococcus oralis bacteriemia. Transthoracic echocardiography revealed an aortic insufficiency from a bicuspid aortic valve but did not show any vegetation. Treatment was initiated with penicillin and gentamicin then changed to ceftriaxone and continued for a total of 6 weeks. During the workup, multiple teeth extractions were performed. While the patient was followed-up in another medical facility, he presented with diffuse abdominal pain with a low-grade fever (388C) and without vomiting. The white blood cell count was 8.6 g/L and the C-reactive protein was 37 mg/L. While the physical examination revealed a mild diffuse

Percutaneous closure of patent foramen ovale in a patient presenting arterial hypoxaemia and supported with bi-ventricular assist device

tion, with massive passage of micro-bubbles through a PFO. Despite measures designed to reduce especially the right heart pressure, the shunt continued to be clinically significant, therefore we decided to close the PFO, under fluoroscopy and TEE guidance using an Amplatzer PFO occluder via a percutaneous approach [3]. At the end of the procedure the shunt was virtually absent on both fluoroscopy and TEE (Fig. 1). This was further corroborated by a marked improvement in arterial oxygenation during the subsequent days. On day 16, the patient underwent successful cardiac transplantation with a favourable clinical course. Due to a combination of VAD-induced left atrial and ventricular unloading a RLS is generally observed in the presence of an inter-atrial communication [2]. Conservative measures to reduce the degree of RLS by lowering right-sided heart pressures, such as reducing PEEP, reduction of the pressure support ventilation and careful volume management, are often insufficient. In such cases the closure of the intra-atrial communication is necessary, by either a surgical or percutaneous approach [3]. Because PFOs are present in up to 30% of the general population, peri-operative screening with a TEE should be considered prior to implantation of a VAD [4]. Furthermore, the TEE should be preferably performed immediately after the VAD is activated, because almost 20% of PFOs can be detected only in the presence of this artificial, device-generated, right-left atrial gradient [5]. In conclusion, we suggest that when a VAD (left, right or bi-ventricular) has to be implanted, patients should be screened for an inter-atrial communication by TEE [4, 5]. If this is present, surgical closure should be considered during the VAD-implantation [2]. However, if a clinically apparent shunt is documented after VAD implantation, percutaneous closure can be performed safely with a high success rate [3], and should probably be considered first-line treatment.

Papillary fibroelastoma as a cause of cardioembolic stroke

A 41 year old previously healthy woman presented with left sided motor deficit. Nuclear magnetic resonance imaging of the brain showed a recent ischaemic lesion of the right thalamus. Transthoracic echocardiography was normal. …