Persistent contamination of heater-cooler units for extracorporeal circulation cured by chlorhexidine-alcohol in water tanks

Recently, surgical site infections due to non-tuberculous mycobacteria (NTM) have been linked to heater-cooler unit contamination. The European Centre for Disease Prevention and Control and manufacturers now recommend the use of hydrogen peroxide in filtered water to fill heater-cooler unit tanks. After implementation of these measures in our hospital, heater-cooler units became heavily contaminated by opportunistic waterborne pathogens such as Pseudomonas aeruginosa and Stenotrophomonas maltophilia. No NTM were detected but fast-growing resistant bacteria could impair their detection. The efficiency of hydrogen peroxide and chlorhexidine-alcohol was compared in situ. Chlorhexidine-alcohol treatment stopped waterborne pathogen contamination and NTM were not cultured whereas their detection efficiency was probably improved.

Source-case investigation of Mycobacterium wolinskyi cardiac surgical site infection

The non-tuberculous mycobacteria (NTM) Mycobacterium wolinskyi caused bacteraemia and massive colonization of an aortic prosthesis in a patient 16 days after cardiac surgery, necessitating repeat surgery and targeted antimicrobial chemotherapy. The infection control team investigated the source and conditions of infection. Peri-operative management of the patient complied with recommendations. The environmental investigation showed that although M. wolinskyi was not recovered, diverse NTM species were present in water from point-of-use taps and heater-cooler units for extracorporeal circulation. This case and increasing evidence of emerging NTM infections in cardiac surgery led to the implementation of infection control procedures in cardiac surgery wards.

Les anévrismes des artères digestives. À propos d'un cas clinique de localisation anévrismale multiple et revue de la littérature

Visceral artery aneurysms constitute a rare vascular disease, with a risk of rupture associated to a high mortality. Often asymptomatic, they are discovered following a routine radiological examination. We present the case of a 71-year-old patient with multiple aneurysms involving the celiac trunk, the splenic artery, and the common hepatic artery. The surgical treatment consisted of an aortohepatic bypass using polytetrafluoroethylene prosthesis, after exclusion of all the aneurysms. The angiography and postoperative angioscan demonstrated the perfect patency of the prosthesis, totally excluding the aneurysms. Given the variety of presentations and the absence of precise predictive factors, there is no therapeutic consensus so far. Surgery is the first therapeutic choice. Endovascular treatment by angioembolization must be reserved for particular conditions. The purpose of this article is to propose the best therapeutic approach on the basis of evidence in the literature.

[Detection and surgical treatment of induced ventricular tachycardia in postinfarction left ventricular aneurysm]

A clinical case of a patient aged 56 years with postinfarction left ventricular aneurysm not complicated with ventricular tachyarrhythmias is presented electrophysiological investigation. Left ventricular aneurysmectomy supplemented with endocardial cryodestruction was carried out. At electrophysiological investigation after surgery ventricular tachycardia could not be induced. In 2 years postoperatively no ventricular tachyarrhythmias were noted. The condition of the patient is satisfactory, corresponds to NYHA class I.

Recurrence of postoperative aortic fistulas: is there an ideal method of prevention? A case report

There are very few cases in English literature of recurrent postoperative aortic fistulas (RPAFs). These are neo-communications between the aortic bloodstream and the lumen of contiguous organs which occur after unpredictable periods from surgical treatment of a previous fistula. The supradiaphragmatic aorta may fistulize into the airways, pulmonary circulation, oesophagus, and cardiac chambers; the infradiaphragmatic aorta into the intestine, stomach, and vena cava. According to the etiology, aortic fistulas are categorized as postoperative (or secondary) and spontaneous (or primary), and RPAF may be considered a subgroup of secondary fistulas. They may recur even more times in the same patient, hence the role of prevention is of the utmost importance. The simultaneous respect of different surgical principles is crucial to make the risk of recurrence less likely. Surgical treatment represents a real challenge due to the emergency conditions and redo nature of operations. Mortality rate is very high. In this article, we describe a case of recurrent aorto-duodenal communication, we discuss the principles of prevention both for the supra and infradiaphragmatic aorta, we introduce some modifications to the classic categorization and we present the first RPAF literature review.

Internal thoracic arterial grafts evaluation by multislice CT scan: a preliminary study

BACKGROUND AND AIM

The internal thoracic artery (ITA) has a better long-term patency than saphenous veins, and anastomosis between ITA and the left anterior descending artery (LAD) represents the "gold-standard" of surgical myocardial revascularization. The aim of this study is to evaluate the multidetector multislice CT Scan (MCTS) as a means of postoperative evaluation of ITA coronary artery bypass grafts.

METHODS

Twenty-eight patients having been operated on for coronary artery bypass with ITA during a 6-months period, benefited, 7 days after surgery, from a patency and anastomotic site control of ITA with a MCTS associated with cardiac gating (Light Speed, General Electric, USA).

RESULTS

Internal thoracic artery bypasses are visualized perfectly on all their courses, with possibility of 3D reconstructions, showing the relationship between cardiac cavities and the arterial bypasses. The anastomotic site on the LAD was, in selected cases, perfectly visualized. Sequential bypasses with left ITA are well visualized as well as T or Y right-to-left ITA grafts. However, surgical clips create some image artefacts.

CONCLUSIONS

The postoperative control of ITAs are possible by MCTS with a satisfactory resolution. This makes it possible to check the patency of ITAs, their course on the heart surface, and the location and quality of anastomosis with a noninvasive reproductive method.

[Surgery of ventricular tachycardia in post-infarction left ventricular aneurysm]

The treatment of post-infarction ventricular tachycardias with antiarrhythmic drug therapy, implantable automatic defibrillators, radiofrequency ablation, also includes different surgical procedures such as endocardial resection of the infarct scar, encircling endocardial ventriculotomy and endocardial cryoablation or thermoexclusion by laser. These procedures may be extensive or limited, guided or not by preoperative mapping. The aim of this review of the literature is to update our knowledge of these different surgical techniques and to define their indications.

High Prevalence of Small Dense LDL as an Underestimated Component of Heart Transplantation–Induced Dyslipidemia: Potential Role in Graft Coronary Vasculopathy?

Heart transplantation-induced dyslipidemia is a recognized risk factor for cardiac allograft vasculopathy that affects survival prognosis. Beyond increased lipids, low-density lipoprotein (LDL) size and systemic factors, including glucose intolerance, oxidative stress, and inflammation, must be taken into account as components of the atherosclerotic risk. The aim of this study was to explore the atherogenic profile of heart transplant recipients (HTR) by assessing lipid parameters, glycemia, oxidative stress status, and inflammation in 59 transplant patients (follow-up of 6 +/- 3 years) compared to 20 healthy volunteers. Classical hypercholesterolemia and hypertriglyceridemia were observed in HTR compared to controls, associated with increased apoCIII levels (0.13 +/- 0.6 vs 0.07 +/- 0.03 g/L, P < .01). Mean LDL size was reduced in HTR compared to controls (25.22 +/- 0.72 vs 26.06 +/- 0.54 nm, P < .001) with an abnormally high prevalence (69% vs 0%, P < .001) of small dense LDL (<25.5 nm). Hyperglycemia (7.3 +/- 3 vs 5.4 +/- 0.8 mmol/L, P < .05) and inflammation (high-sensitive CRP: 3.1 +/- 3 vs 1.6 +/- 0.9 mg/L, P < .001) were evidenced in HTR since no difference in oxidative stress parameters was observed. In conclusion, a high prevalence of small dense LDL is an important component of posttransplantation dyslipidemia.

Topical negative pressure therapy. A very useful new method to treat severe infected vascular approaches in the groin

AIM

The treatment of infected vascular surgery sites is challenging. Negative pressure applied uniformly to the entire wound surface has been shown to allow granulation tissue formation and to promote healing of acute and chronic wounds.

METHODS

We used the Vacuum-Assisted Closure (VAC, Kinetic Concepts Incorporated, San Antonio, Texas, USA) system in 4 patients with severe groin wound infection after emergency surgery on the femoral artery.

RESULTS

In all 4 patients, general health improved and the wound changed rapidly from a large infected cavity to a minor lesion readily covered using a simple surgical technique.

CONCLUSION

This study establishes VAC as a very valuable tool for managing severe complications of groin vascular surgery sites even in patients with obesity and/or diabetes mellitus.

[Cardiac surgery in the octogenarian: what risks for what benefits?]

About 1 to 8% of patients referred for cardiac surgery in industrialised countries are octogenarians. Hospital mortality is high and depends on age, type of surgery and other predictors of death which are female gender, left congestive heart failure, history of myocardial infarction, chronic obstructive lung disease, renal insufficiency, carotid and others vascular diseases. Morbidity is also very high. Besides supraventricular arrhythmias, respiratory failure is the main cause (20 to 30%) of morbidity, followed by cerebrovascular accident and renal failure. Due to this high rate of postoperative events, the length of stay is significantly increased. At follow-up however, excellent functional status and survival rate is afforded by the operative procedure. The main problem remains the selection of patients in order to improve results.

[Extracorporeal circulation: an extraordinary tool that is not just for cardiac surgeons]

Extracorporeal circulation (ECC) is not only used for open heart surgery. There are also other surgical and medical applications. ECC can be used for encephalic arteries surgery to induce hypothermia and maximally protect the brain. Femoro-femoral ECC may be needful for urgent traumatologic surgery of the supra-aortic trunci. Intracranial aneurysm repair can occasionally necessitate deep hypothermia and circulatory arrest with ECC. Renal cell carcinomas may metastasize to the right atrium and surgery with ECC is mandatory for complete excision. Some reports in the literature mention use of ECC for hepatic surgery of intra-hepatic aneurysms. With acute peripheral ischemia, metabolites in the affected limb can be washed out with good results. Medical indications for ECC are numerous with pulmonary assistance as one of the foremost when mechanical ventilation failed. Homogeneous and rapid rewarming of hypothermic patients can be achieved with ECC. Finally, some groups have reported the use of ECC to administer chemotherapy in limb melanoma.

Simple surgical technique to prevent direct secondary aortoenteric fistulas

To prevent direct secondary aortoenteric fistulas, a devastating complication of abdominal aortic surgery, we describe here a rapid, very easy to perform and no cost operating technique. A part about 4 cm long of the vascular prosthesis was cut to obtain a partial tailored ring which was passed through the prosthesis. After the anastomosis was realized, the tailored ring was hitched up to totally cover proximal anastomosis and prevent direct contact between aorto-prosthetic anastomosis and the bowel.

[Chronic constrictive pericarditis in African children: report of a case]

The chronic constrictive pericarditis is a rare affection, with multiple etiologies and concerning especially the adult. We report a case of chronic constrictive pericarditis in an African child in whom no etiology was found. A review of the literature raises the characteristics of chronic constrictive pericarditis for a better therapeutic management.

[Results of coronary artery surgery in octogenarians]

Over an 11 year period from January 1990 to December 2000, 3282 patients underwent isolated or combined surgical myocardial revascularisation. In this group, 42 were aged 80 or over (maximum 87 years), 1.3% of the total patient population. The mean age of this subgroup was 81.8 +/- 1.75 years) with a male predominance (61.9%). All patients were autonomous and considered to be in good general and psychological health. Preoperative coronary angiography showed 33.3% of left main stem lesions either alone or associated with a right coronary lesion. The ejection fraction was over 50% in 78.6% of cases. Saphenous vein grafts were used in all but 5 patients who also had left internal mammary artery grafts. Thirteen patients (31%) underwent combined valvular surgery (11 aortic and 2 mitral valve) and 2 patients underwent combined vascular surgery. Three patients were operated as an emergency. A total of 5 patients died in the first 30 postoperative days, a hospital mortality of 11.9%. There were 2 postoperative hemiplegias and 2 cases of renal failure which were aggravated in the postoperative period. The other patients were discharged from hospital with a satisfactory cardiac and functional status. The global mortality was 14% at 3 years and 18% at 5 years. The main bad prognostic factor for survival was the association of aortic valve surgery. In selected octogenarians in good general and psychological health without severe co-morbid conditions, surgical myocardial revascularisation may be considered with an acceptable operative risk.

Cyclosporin A increases basal intracellular calcium and calcium responses to endothelin and vasopressin in human coronary myocytes

Cyclosporin A (CsA) is a widely used immunosuppressive agent with severe side effects including hypertension. Here, we investigated the effects of CsA on intracellular free calcium ([Ca(2+)](i)) and the mechanisms involved in vasoconstriction in cultured human coronary myocytes. We used the Fura-2 technique for Ca(2+) imaging. Acute application of CsA at therapeutic concentrations (0.1-10 micromol/l) had no effect. Chronic exposure to CsA (1 micromol/l) for 24 h induced a small (20 nmol/l) but highly significant increase of basal [Ca(2+)](i) and enhanced the occurrence of spontaneous Ca(2+) oscillations. Endothelin- and vasopressin-induced rises of [Ca(2+)](i) were also enhanced. The demonstration that CsA increases basal [Ca(2+)](i) in addition to its impact on agonist receptor stimulation is of major importance for new therapeutic approaches.

Aspergillus flavus mitral valve endocarditis after lung abscess

A 16-year-old male with bone marrow failure due to chemotherapy for recurrent acute lymphoblastic leukemia developed an abscess in the lower lobe of the left lung draining through a bronchogastric fistula, as well as mitral valve endocarditis with large vegetations. After a course of antifungal therapy, the left lobe was removed and the fistula closed. The mitral valve was then replaced, after a failed attempt at valve repair, by a mechanical, double-leaflet prosthesis. Microscopy of the lung and heart specimens disclosed hyphae. Cultures of both specimens on Sabouraud's medium recovered a fungus, which was identified by culturing on Czapek's medium as Aspergillus flavus. Despite further antifungal therapy, fatal embolism developed. The emboli contained the same A. flavus as the valve and lung specimens. This case confirms the grim prognosis of primary Aspergillus endocarditis in immunocompromised patients, and suggests that delayed surgical treatment and the presence of another focus of Aspergillus infection may increase the risk of death.

Postoperative exercise tolerance after aortic valve replacement by small-size prosthesis: functional consequence of small-size aortic prosthesis

OBJECTIVES

The objective of this study was to determine whether a small-size valve prosthesis contributes to exercise intolerance, as assessed by VO2 measurement during an exhaustive cycle ergometer exercise.

BACKGROUND

The determinants of exercise capacity after mechanical aortic replacement are not well known. The selection of small valve sizes has, however, been described as an independent predictor of exercise intolerance as assessed by exercise duration. Maximal oxygen uptake (VO2max) is a good index of exercise tolerance.

METHODS

Fourteen patients were eligible, with a mean age of 62 +/- 6 years. Before surgery, the mean left ventricular ejection fraction (LVEF) was 73 +/- 8%. Two valve types with small diameter (19 to 21 mm) were used: Medtronic Hall and St Jude Medical. A healthy sedentary control group (n = 14) paired for age, weight and size was constituted. After one year of follow-up, cardiorespiratory tests were performed. In addition, the gradients through the prostheses were determined by continuous pulse Doppler at rest and immediately after the cardiorespiratory test. RESULTS The exercise tolerance was not significantly different between the control group and patient group: VO2 peak (21.7 vs. 20.4 ml/kg/min; p = 0.42), workloads (115 vs. 93 W; p = 0.13) and ventilatory parameters were similar. The mean and peak gradients at rest and during exercise were not correlated with VO2max.

CONCLUSIONS

Valve replacement by small aortic prosthesis does not seem to be a factor of exercise intolerance as assessed by VO2max in patients without LVEF dysfunction before surgery.

[Is atypical sodium current related to arterial pathophysiology?]

Primary cultured human coronary myocytes, derived from patients with end-stage heart failure (NYHA, classes III and IV) caused by an ischemic disease and undergoing heart transplantation, express a voltage-gated tetrodotoxin-sensitive sodium current (INa). This current has atypical electrophysiological and pharmacological properties and regulates intracellular sodium ([Na+]i) and calcium ([Ca2+]i). Our work is aimed at identifying its role and regulation of expression during pathophysiology. We currently investigate whether INa is expressed in vascular smooth muscles cells (VSMCs) isolated from either healthy or diseased (atheromatous) arteries in human and, in parallel, in pig, rabbit and rat. Cells were enzymatically isolated, primary cultured and macroscopic INa were recorded using the whole cell patch clamp technique. We found that INa is expressed in VSMCs grown from human aortic (90%; n = 48) and pulmonary (44%; n = 16) arteries and in the human aortic cell line HAVSMC (94%; n = 27). INa was also detected in pig coronary (60%; n = 25) and rabbit aortic (47%; n = 15) VSMCs, but not in rat aortic myocytes (n = 30). These different INa were activated at similar range of potentials (approximately -45 mV), had similar sensitivity to tetrodotoxin (IC50 around 5 nM) and similar density (2 to 4 pA/pF). Their expression was related to cell dedifferentiation in vitro. However, INa was observed more frequently in human myocytes derived from diseased arteries (ischemic cardiopathy) than in those derived from healthy tissues (dilated cardiopathy). In conclusion, INa may contribute to increase the basal arterial contractility and play a role in pathological situations including hypertension.

Vertebral artery surgery with cardiopulmonary bypass and deep hypothermia

Deep hypothermia was proposed to prevent neuronal ischemia and stroke during surgical procedures on arteries that supply the brain, especially with extended occlusive lesions on both internal carotid arteries. The interest of this therapeutic option is still under discussion, even in the case of combined cardiac and cerebrovascular surgery. We report the case of a 53-year-old male who was admitted to our institution for symptomatic vertebrobasilar insufficiency. Angiography showed a thrombosis of both internal carotid arteries, stenosis of both external carotid arteries, and a tight proximal stenosis of a dominant right vertebral artery. Endarterectomy and angioplasty of the origin of the right external carotid artery was done first to increase the blood supply to the brain via collateral arteries connecting the extra- and intracranial networks. Six weeks after this, a right-sided vertebral-to-carotid artery anastomosis was performed during cardiopulmonary bypass (CPB)-induced deep hypothermia for optimal neuronal protection, with good results. However, early thrombosis of the right vertebral artery requiring reintervention in normothermia, without any stroke, indicate that deep hypothermia was unnecessary in this case, probably because of the previous natural and surgical development of collateral circulation. However, there was no means of predicting this in a reliable manner before the procedure and deep hypothermia appeared a safe technique for neuronal protection without any specific postoperative complications.

Regulation of Ca2+ homeostasis by atypical Na+ currents in cultured human coronary myocytes

Primary cultured human coronary myocytes (HCMs) derived from ischemic human hearts express an atypical voltage-gated tetrodotoxin (TTX)-sensitive sodium current (I(Na)). The whole-cell patch-clamp technique was used to study the properties of I(Na) in HCMs. The variations of intracellular calcium ([Ca2+]i) and sodium ([Na+]i) were monitored in non-voltage-clamped cells loaded with Fura-2 or benzofuran isophthalate, respectively, using microspectrofluorimetry. The activation and steady-state inactivation properties of I(Na) determined a "window" current between -50 and -10 mV suggestive of a steady-state Na+ influx at the cell resting membrane potential. Consistent with this hypothesis, the resting [Na+]i was decreased by TTX (1 micromol/L). In contrast, it was increased by Na+ channel agonists that also promoted a large rise in [Ca2+]i. Veratridine (10 micromol/L), toxin V from Anemonia sulcata (0.1 micromol/L), and N-bromoacetamide (300 micromol/L) increased [Ca2+]i by 7- to 15-fold. This increase was prevented by prior application of TTX or lidocaine (10 micromol/L) and by the use of Na(+)-free or Ca(2+)-free external solutions. The Ca(2+)-channel antagonist nicardipine (5 micromol/L) blocked the effect of veratridine on [Ca2+]i only partially. The residual component disappeared when external Na+ was replaced by Li+ known to block the Na+/Ca2+ exchanger. The resting [Ca2+]i was decreased by TTX in some cells. In conclusion, I(Na) regulates [Ca2+]i in primary cultured HCMs. This regulation, effective at baseline, involves a tonic control of Ca2+ influx via depolarization-gated Ca2+ channels and, to a lesser extent, via a Na+/Ca2+ exchanger working in the reverse mode.

Malignant ventricular arrhythmias revealing anomalous origin of the left coronary artery from the pulmonary artery in two adults

We report two cases of anomalous origin of the left coronary artery from the pulmonary artery (ALCAPA), revealed by malignant ventricular arrhythmias in adult patients. A two coronary system was re-established in both patients, and cryotherapy was performed on one of the patients who, in addition, presented ventricular aneurysm triggering ventricular tachycardia.

Large encircling cryoablation without mapping for ventricular tachycardia after anterior myocardial infarction: long-term outcome

OBJECTIVE

Map-guided procedures have been the accepted standard for ventricular tachycardia surgery. However, promising results of visually guided resections without mapping have been reported. The goal of this study was to evaluate the efficacy of large encircling cryoablation without mapping for ventricular tachycardia after anterior myocardial infarction.

METHODS

Between 1985 and 1996, this procedure, along with aneurysmectomy, was performed on 38 patients for malignant ventricular tachycardia. The mean interval between the operation and myocardial infarction was 59.2 months; 7 patients (18.4%) were operated on within 1 month of myocardial infarction. The mean patient age was 62.1 +/-7.3 years and the mean left ventricular ejection fraction was 29.0% +/-7.2%.

RESULTS

Hospital mortality was 2.6% (1 patient). The electrical success rate based on postoperative electrophysiologic studies was 94.5%. Overall electrical success rate was 89.1%. Freedom from ventricular tachycardia was 77% (95% CI 61%-94%) at both 5 and 7 years. Freedom from sudden cardiac death was 91% (95% CI 80%-100%) at both 5 and 7 years, with overall actuarial survivals at 5 and 7 years of 63% (95% CI 47%-80%) and 42% (95% CI 22%-63%), respectively. The main cause of late death was congestive heart failure in 62.6% of these patients.

CONCLUSIONS

One can achieve good results without intraoperative mapping in the treatment of patients with ventricular tachycardia after anterior myocardial infarction by using large encircling cryoablation.

[Extracorporeal circulation for warming in severe accidental hypothermia. 3 cases]

BACKGROUND

Severe accidental hypothermia with central temperature below 28 degrees C can result from prolonged cold exposure and lead to a fatal outcome by spontaneous or provoked ventricular fibrillation.

CASE REPORT

Three patients were referred for central temperature below 24 degrees C. At admission, the patients had major ventricular rythm disorders (two were in a state of circulatory arrest and the third had auricular fibrillation and circulatory collapse). Emergency care associated internal warning using extracorporeal circulation via the femoro-femoral route with a centrifuge pump. Outcome was favorable in 2 cases.

DISCUSSION

Prognosis is very poor in patients who experience severe accidental hypothermia (< 28 degrees C) with circulatory collapse. Death often results from major rhythm disorders. Optimal emergency rewarming and oxygenation using extracorporeal circulatory assistance can be successful.

[Outcome of type I acute aortic dissection operated after 70 years of age. A retrospective study of operated dissection of the aorta in the over 70 years old]

The aim of this study was to assess the perioperative mortality and long-term outcome of Type I dissection of the aorta operated in patients over 70 years age. Of the 87 dissections of the aorta operated between 1988 and 1995, 19 concerned patients aged 71 to 79 (average 74.1 +/- 2.4 years). The procedure was replacement of the ascending aorta with gluing of the false lumen in call ases. Two patients also underwent aortic valve replacement and three also had replacement or repair of the aortic arch. Eleven patients (56%) had circulatory arrests lasting an average of 33 minutes (10-86 minutes). The mortality rate at 30 days was 31.5% (6/19): 3 deaths were due to bleeding, 1 to mesenteric infarction, 1 to cardiac arrhythmia and 1 to a cerebrovascular accident. The morbidity was 53%, mainly due to neurological complications, chest infection and renal failure. After an average period of 36.8 months (range: 3 to 75 months) with no patient lost to follow-up, the late mortality was 23% (3/13), giving actuarial survival rates at 1.5 and 6 years of 63%, 47.5% and 32%, respectively (including the operative mortality). Or the survivors, 9 were in NYHA Classes I-II and 1 in class III. One patient developed a hemiparesis. The authors conclude that, despite high mortality and morbidity at 30 days, long-term survival and its quality are arguments in favour of surgical management, even in elderly patients.

Mycotic aneurysm of the extracranial carotid artery: an uncommon complication of bacterial endocarditis

This report describes a case involving mycotic aneurysm of the extracranial internal carotid artery occurring as a complication of staphylococcal endocarditis in a patient with systemic lupus erythematosus. Three main points are emphasized: (1) this complication occurred in an immunodepressed patient; (2) surgical treatment consisted of aneurysmorraphy using absorbable suture; (3) the outcome was successful with a follow-up of 24 months.

Voltage-gated calcium channel currents in human coronary myocytes. Regulation by cyclic GMP and nitric oxide

Voltage-gated Ca2+ channels contribute to the maintenance of contractile tone in vascular myocytes and are potential targets for vasodilating agents. There is no information available about their nature and regulation in human coronary arteries. We used the whole-cell voltage-clamp technique to characterize Ca2+-channel currents immediately after enzymatic dissociation and after primary culture of coronary myocytes taken from heart transplant patients. We recorded a dihydropyridine-sensitive L-type current in both freshly isolated and primary cultured cells. A T-type current was recorded only in culture. The L- (but not the T-) type current was inhibited by permeable analogues of cGMP in a dose-dependent manner. This effect was mimicked by the nitric oxide-generating agents S-nitroso-N-acetylpenicillamine (SNAP) and 3-morpholinosydnonimine which increased intracellular cGMP. Methylene blue, known to inhibit guanylate cyclase, antagonized the effect of SNAP. Inhibitions by SNAP and cGMP were not additive and seemed to occur through a common pathway. We conclude that (a) L-type Ca2+ channels are the major pathway for voltage-gated Ca2+ entry in human coronary myocytes; (b) their inhibition by agents stimulating nitric oxide and/or intracellular cGMP production is expected to contribute to vasorelaxation and may be involved in the therapeutic effect of nitrovasodilators; and (c) the expression of T-type Ca2+ channels in culture may be triggered by cell proliferation.

[Paraplegia after surgical treatment of primary aorto-duodenal fistula]

A 68-year-old patient with chronic cirrhosis underwent surgical repair of the subrenal abdominal aorta presenting an aorto-duodenal fistula. The fistula was considered to be a primary fistula because it occurred without prior surgery and because the aorta had ruptured without formation of an aneurysm. The postoperative period was complicated by paraplegia further compromising the outcome in this severe condition. In general, there are several problems involved in the management of aorto-duodenal fistulae. Neither computed tomography of the abdomen nor gastroduodenal endoscopy are able to provide the diagnosis in all cases before surgery. Surgical treatment is most often conducted in an emergency setting requiring repair of both the digestive tract and of the vascular lesions. It is also important to recognize the risk of neurological events occurring intra-operatively. Prognosis is usually poor.

[Traumatic tricuspid insufficiency. Apropos of 2 cases]

The authors report two cases of tricuspid regurgitation by a ruptured anterior papillary muscle secondary to non-penetrating thoracic trauma. In the presence of suggestive clinical and electrocardiographic abnormalities (systolic murmur, right heart failure, right bundle branch block), echocardiography confirmed the tricuspid regurgitation, showed its mechanism and excluded any other intracardiac lesions. Tricuspid annuloplasty was performed in both cases because of the persistence of failure or degradation of the patient's clinical condition. Peroperative echocardiography was used to judge the quality of the surgical repair in both cases. Traumatic tricuspid regurgitation is a rare condition and the diagnosis is often delayed. Echocardiography is the investigation of choice and guides treatment which is essentially valvular repair in symptomatic patients.

Use of active shunt for surgical repair of intrapericardial inferior vena caval injury

We report a case of intrapericardial inferior vena caval disruption due to goring by a bull, and we describe the surgical repair of this uncommon penetrating cardiac injury. Review of the literature indicates that, as with other penetrating cardiac injuries, this rare lesion requires aggressive treatment involving an emergency thoracotomy. The use of an atrial caval active shunt was necessary for successful surgical management, and therefore we conclude that surgical treatment of this lesion is comparable with surgical repair of hepatic veins and retrohepatic vena caval injuries incurred during blunt vascular trauma or penetrating abdominal injuries.

Repair of the aortic arch with fibrin glue in type A aortic dissection

Location of the intimal tear in the aortic arch in type A aortic dissection is for many authors an indication for replacement of the aortic arch, but this operation has a high in-hospital mortality rate: 20% to 40%. Instead, we suggest repairing the aortic arch by injecting fibrin glue, which contains a human sealer protein concentrate, between the two dissected layers under circulatory arrest while replacing the ascending aorta. To evaluate this technique, we reviewed 45 successive patients operated on for type A acute aortic dissection between January 1989 and July 1993, of which 6 had the intimal tear located on or extending into the aortic arch. Mean age was 71 +/- 4.2 years (range 68 to 74). After proximal supracoronary anastomosis with a collagen-impregnated graft, aortic arch repair was achieved by injecting fibrin glue between the two layers, using circulatory arrest at a mean temperature of 22 degrees C, with a mean duration of 24 minutes. This obliterated the dissection in the arch and also the intimal flap. The distal part of the graft was then anastomosed to the proximal portion of the aortic arch at the origin of the innominate artery under circulatory arrest. There were no early or late deaths. All patients were asymptomatic at a mean follow-up of 2.6 years. Follow-up angioscan showed obliteration of the dissection in the aortic arch in all patients; there were two patients with dilatation of the distal aortic arch of 40 and 45 mm.(ABSTRACT TRUNCATED AT 250 WORDS)

[Surgery for arrhythmias]

The role of surgery in the treatment of cardiac arrhythmias has been marginalized in recent years with the rise in eminence of radiofrequency current ablation especially in the Wolff-Parkinson-White syndrome and nodal reentrant tachycardia. The indications of antiarrhythmia surgery for ventricular arrhythmias have become standardised. The unquestioned efficacy of the surgical techniques proposed (endarterectomy or cryosurgery with or without peroperative mapping) should not be associated with unacceptable mortality rates as when left ventricular function is too poor, implantation of a defibrillator is always possible. In the domain of atrial fibrillation, the interventions proposed (corridor or maze procedures) do not have the foundations that the follow-up of a sufficient number of cases would confer but they have the merit, especially the latter, of taking the underlying physiopathological mechanisms into consideration.

Aortic valve repair with fibrin glue for type A acute aortic dissection

Repair of the acute aortic insufficiency associated with type A aortic dissection is now preferred to valve replacement. This is generally achieved by resuspending the aortic valve using different types of suturing techniques, with sutures usually passing through the aortic wall, which causes bleeding at the suture sites. We suggest, instead, simply injecting fibrin glue between the two dissected layers of the aortic annulus, which achieves resuspension of the aortic valve and reinforces the proximal stump without the need for any sutures. To evaluate the efficacy of this simple technique, the cases of 15 consecutive patients who underwent operative intervention for the treatment of the type A aortic dissection associated with acute aortic insufficiency between January 1989 and July 1993 were reviewed. The mean patient age was 63 +/- 11.2 years (range, 43 to 74 years). All had massive 3+ or 4+ aortic insufficiency, documented pre-operatively by transesophageal echocardiography. None had any history of aortic regurgitation. In all patients, the aortic repair was done in conjunction with a supracoronary replacement of the ascending aorta with a collagen-impregnated graft attached using a running suture, after reinforcement of the dissected tissues with glue. There was one non-valve-related early death (6.7%) and no late mortality. At a mean follow-up of 2.3 years, all patients were in New York Heart Association functional class I and had a mean aortic insufficiency grade of 0.3 (range, 0 to 1+). Follow-up computed tomography in all patients showed closure of the dissecting process on the proximal ascending aorta.(ABSTRACT TRUNCATED AT 250 WORDS)

[Value of the superior trans-septal approach in mitral valve replacements]

Mitral valve exposure is widely improved by the superior-transseptal approach (STS). The diffusion of this technique has been restricted because of the possibility of detrimental effects of sino-atrial arrhythmias, especially in patients in sinus rhythm preoperatively. Between April 1991 and December 1992, we performed mitral valve replacement (MVR) on 55 patients by an STS approach. The mean age was 57.7 +/- 11.3 years (38-75 years). 21 were reoperations and 1 patient had been operated twice. The procedure consisted in 10 MVR with a bioprosthetic valve and 45 with a mechanical valve. Associated procedures were 5 tricuspid annuloplasties, 13 aortic valve replacements, 1 tricuspid valve replacement, 4 CABG, and 1 aneurysm resection. Overall hospital mortality was 9.1 +/- 3.8% (5/55). Mortality for isolated MVR was 6.2 +/- 4.2% (2/32). 51% (28/55) were in sinus rhythm (SR) preoperatively, 43% (12/28) of them had never presented atrial fibrillation. Postoperatively among those 28 patients in SR, 20 remained in SR, 7 were in atrial fibrillation, and 1 in atrial flutter. 3.6% (2/55) needed transient electrosystolic pacing for very slow atrial fibrillation 20% (11/55) have presented a transient sino-atrial dysfunction; None of these rhythmic events had any adverse effect. Finally, the very good visibility and accessibility are the major advantages of this approach, especially in mitro-tricuspid combined procedures, in small left atrium and repeat surgery. As sino-atrial arrhythmias are transient, we think this approach can be routinely employed in MVR.

Fibrin sealant for early repair of acquired ventricular septal defect

The trend toward early operation for acquired ventricular septal defects exposes the patient to major perioperative bleeding and residual shunt because of the fragility of the recently necrosed myocardium. To reduce these complications we have used a fibrin sealant to reinforce the cardiac tissues in addition to the usual closure of the defect with a Dacron patch through a left ventricular septum around the defect, area. During cardiac arrest fibrin sealant is applied on the ventricular septum around the defect, between the septum and the patch, and on the edges of the ventriculotomy. This technique was used in three patients (mean age 68.2 years) operated on for an acquired ventricular septal defect within 4 days of the infarction and within 24 hours of the occurrence of the defect. Low postoperative bleeding, absence of recurrent shunt, and good ventricular function indicated satisfactory surgical result in all three patients. We suggest that the use of fibrin sealant during operations for acquired ventricular septal defects, by reinforcing the necrotic and fragile tissues, may reduce perioperative bleeding and assure a more solid implantation of the patch.

Fibrin sealant improves surgical results of type A acute aortic dissections

From January 1984 to July 1990, 63 patients were operated on for type A acute aortic dissection. Forty-two patients (aged 22 to 80 years) had isolated replacement of the ascending aorta with the following techniques: group 1 (n = 10) had replacement of the ascending aorta with an intraluminal sutureless graft, group 2 (n = 14) had a Dacron prosthesis sutured to the aorta, and in group 3 (n = 18) the proximal and distal aortic stumps were glued together and reinforced at the suture sites with fibrin sealant before implantation of the Dacron prosthesis. There were no significant differences between the three groups with respect to age, sex, or preoperative clinical and anatomical data. Three (30%) intraoperative deaths occurred in group 1, 4 (29%) in group 2, and none in group 3. Cross-clamp and extracorporeal circulation time were significantly lower in group 1 when compared with groups 2 and 3. Perioperative blood loss during the first 24 hours was significantly lower in group 3 (372 +/- 155 mL) when compared with group 1 (755 +/- 210 mL; p less than 0.05) or group 2 (1,055 +/- 370 mL; p less than 0.01). Total hospital mortality was 7 (70%) in group 1, 6 (43%) in group 2, and 1 (5.5%) in group 3. All patients were reviewed: one late death occurred in group 2 and none in the other groups. All survivors were in good clinical condition. In conclusion, intraluminal sutureless grafts allowed shorter cross-clamp and extracorporeal circulation time but did not improve surgical results for treatment of type A acute aortic dissections.(ABSTRACT TRUNCATED AT 250 WORDS)

[A rare etiology of rectal bleeding: Meckel's leiomyoblastoma. Value of celiomesenteric arteriography]

A rare case of leiomyoblastoma developing in Meckel's diverticulum and revealed by massive rectorrhagia is reported. The characteristic clinicopathologic features of these tumors in their small intestine localization are described and the value of celiomesenteric arteriography emphasized for their topographic and even nosologic diagnosis.

[Surgical treatment of gastroesophageal reflux in children. Apropos of 77 cases]

Seventy-seven children with gastro-esophageal reflux have been operated upon during the last 21 years. Gradually added to the classical digestive symptoms and signs were those of respiratory disorders varying between asthma and the "missed sudden death" syndrome. Analysis of anatomical forms showed a predominance of cardio-antral malpositionings (58%) in this age group (mainly young babies). Surgical treatment, presently based on that of Toupet, apart from classical formal indications, is conducted after 3 to 4 months of medicopostural therapy when there is persistence of reflux and/or of esophagitis on fibroscopy in cardio-antral malpositions. Particularly as results of this surgery are good (disappearance of reflux in 83% of cases).