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Biomedical subjects

G Babatasi

Publications and source records attributed to G Babatasi.

At least 55 records · Page 3Linked to original sources
PubMed1998

Proarrhythmic and antiarrhythmic effects of bupivacaine in an in vitro model of myocardial ischemia and reperfusion.

BACKGROUND: Bupivacaine may have toxic cardiovascular effects when accidentally administered by intravascular injection. However, its electrophysiologic effects in the presence of myocardial ischemia remain unknown. The authors evaluated the electrophysiologic and anti- and proarrhythmic effects of bupivacaine in an in vitro model of the ischemic and reperfused myocardium. METHODS: In a double-chamber bath, a guinea pig right ventricular muscle strip was subjected partly to normal conditions and partly to simulated ischemia followed by reperfusion. The electrophysiologic effects of bupivacaine were studied at 1, 5, and 10 microM concentrations. RESULTS: Bupivacaine (5 and 10 microM) decreased the maximal upstroke velocity of the action potential (Vmax) in normoxic conditions and further decreased (10 microM) the Vmax decrease induced by ischemic conditions. Bupivacaine reduced the mean occurrence time to the onset of myocardial conduction blocks (9 +/- 3 min; mean +/- SD; P < 0.005 with 5 and 10 microM, compared with 17 +/- 6 min during simulated ischemia with no drug or control), and it increased the number of preparations that became inexcitable to pacing (55% of preparations, with 1 microM and 100% with 5 and 10 microM, compared with 17% for the control group). The incidence of spontaneous arrhythmias was reduced by 5 and 10 microM bupivacaine during ischemia and reperfusion and was enhanced by 1 microM bupivacaine during the ischemic phase. CONCLUSIONS: In guinea pig myocardium under ischemic conditions, bupivacaine induced a loss of excitability at concentrations of 5 and 10 microM. Proarrhythmic effects observed at 1 microM were considered as lower than the cardiotoxic range in normoxic conditions. The incidence of reperfusion arrhythmias was decreased at all concentrations.

Action Potentials↗
PubMed1998

Iodine-123-metaiodobenzylguanidine SPECT of regional cardiac adrenergic denervation in Brugada syndrome.

We present the case of 44-yr-old man who presented syncope with ventricular tachycardia in the setting of Brugada syndrome. In addition to the electrocardiographic evidence of the syndrome and the absence of apparent structural heart disease, clear defects of myocardial neuronal metaiodobenzylguanidine (MIBG) uptake on MIBG SPECT imaging also were found in inferior, apical and septal walls. Thallium-201 SPECT distribution was homogeneous along the left ventricle. Thus, cardiac MIBG scintigraphy provides information about left ventricular dysinnervation in a patient with Brugada syndrome, enhancing the clinical utility of myocardial MIBG SPECT imaging in life-threatening ventricular arrhythmias.

3-Iodobenzylguanidine↗
PubMed1998

[Ehlers-Danlos disease revealed during pregnancy through the diagnosis of aortic dissection].

Dissection of the aorta is a serious condition but rare in young women, and occurring during the 3rd trimester of pregnancy. The main risk factors are hypertension and diseases of the connective tissue or of collagen (Marfan's syndrome and Ehlers-Danlos disease). The authors report a case of dissection of the aorta managed in a pluridisciplinary manner by the anaesthetists, cardiologists, obstetricians and cardiothoracic surgeons, which resulted in a favourable outcome for both mother and baby. The diagnosis of Ehlers-Danlos disease was made from the onset and, over a period of 10 years with CT scan and annual echocardiographic follow-up, total replacement of the supra-coronary aorta was performed in several stages.

Adult↗
PubMed1998

Impairment of cardiac neuronal function in acute myocarditis: iodine-123-MIBG scintigraphy study.

UNLABELLED: Abnormalities of norepinephrine uptake have been found to reflect impairment in adrenergic nerve function that has influenced the cardiac outcome of patients with heart failure. The aim of this study was to explore the cardiac neuronal function by using 123I-metaiodobenzylguanidine (MIBG) scintigraphy in patients with acute myocarditis. METHODS: We studied 15 patients (age range 42 +/- 10 yr) with clinical, biological, electrocardiographic and radionuclide left ventricular ejection fraction (LVEF) (41% +/- 7%) data indicating myocarditis and 10 normal subjects (age range 36 +/- 7 yr, mean radionuclide LVEF 69% +/- 8%, p < 0.05). Fourteen patients had positive histologic findings of myocarditis and 1 had nonspecific histological data. All patients underwent planar cardiac imaging after intravenous injection of 185 MBq 123I-MIBG and right ventricular biopsy within 7 days. A chest anterior view was acquired 4 hr later. Heart-to-mediastinum ratio activity was measured, as previously described in our laboratory. RESULTS: Significant impairment of cardiac neuronal uptake of MIBG was observed and based on a reduction of heart-to-mediastinum ratio (148% +/- 16% versus 234% +/- 36%, p < 0.05). A significant correlation was observed between LVEF and MIBG uptake in patients (y = 1.58x +/- 83.7, r = 0.72, p < 0.01). CONCLUSION: Acute myocarditis is associated with an injury of the cardiac adrenergic neuronal function. In addition to the inflammatory injury of the myocytes, the impairment of adrenergic function may be involved in the cardiac pump failure induced by myocarditis.

3-Iodobenzylguanidine↗
PubMed1998

Recurrent left-sided heart leiomyosarcoma: should heart transplantation be legitimate?

Leiomyosarcoma of the heart is an uncommon primary malignant tumor with poor postoperative survival that may be measured in months. A leiomyosarcoma of the left atrium was diagnosed in a 47-year-old man. Initial admission was for acute pulmonary edema requiring emergency surgery. The tumor involved the left atrial cavity, and a radical resection was performed. Six months later an isolated myxomatous recurrence was detected. Heart transplantation was then performed. The patient is in good health 20 months after operation with no evidence of residual disease or recurrence. The literature has been reviewed. Surgical resection is not an adequate treatment for leiomyosarcoma of the left atrium and early heart transplantation probably offers the only hope for these patients.

Heart Atria↗
PubMed1997

Asymptomatic carotid stenosis in patients undergoing major cardiac surgery: can percutaneous carotid angioplasty be an alternative?

OBJECTIVE: As the mortality associated with coronary artery bypass grafts has fallen, morbidity has become an increasing problem. The improvement of transluminal carotid angioplasty is enlarged to patients with asymptomatic severe carotid stenosis (> 85%) requiring coronary surgery. METHODS: Between January 1993 and January 1995, 10 patients underwent percutaneous carotid angioplasty prior to cardiac surgery (17.4 days). Mean age was 71 +/- 4.3 years. Four patients showed a contralateral occlusion of the internal carotid artery. Transluminal carotid angioplasty was carried out with a triple coaxial catheter system. Six angioplasties required a Strecker stent. RESULTS: Mean follow-up was 11.4 months. No mortality was observed. Only one patient showed a transient hemianopsia. All patients underwent angiography at four months. Two patients required a new procedure of carotid angioplasty completed with a Strecker stent in one case and by dilatation of a stent in another patient. CONCLUSION: The results of transluminal carotid angioplasty, in this short series, are encouraging in this group of high-risk morbidity and mortality (elderly patients, bilateral carotid lesions, multiple coronary arterial grafts).

Aged↗
PubMed1997

Aorto-pulmonary fistula: a rare event in the evolution of a dissecting aneurysm of the thoracic aorta.

The natural history of a thoracic aneurysm is usually towards the dissection or free rupture; rarely an aorto-pulmonary fistula can complicate this lesion. We present two cases of Aorto-pulmonary fistula as acute complication of an aneurysm of thoracic aorta; the etiopathology seem to be related to the same mechanism: a dissecting aneurysm of the ascending aorta leading to a secondary fistulation in the main pulmonary artery. In our two cases the diagnosis was suggested by clinical findings and by Doppler-echocardiography. Both patients were managed surgically with success and both survived.

Adult↗
PubMed1997

Pregnancy with aortic dissection in Ehler-Danlos syndrome. Staged replacement of the total aorta (10-year follow-up).

Pregnancy complicated by aortic dissection in patients with hereditary disorder of connective tissue presents interesting considerations including management of caesarean section with the unexpected need for cardiac surgery in emergency. Generalizations can be made on management principles with long-term follow-up requiring an aggressive individualized approach by a multidisciplinary team. A 33-year-old parturient presenting an aortic dissection at 37 weeks gestation required prompt diagnosis of Ehlers-Danlos syndrome in combination with correct surgical therapy resulted in the survival of both the mother and infant. During the 10-year follow-up, multiple complex dissection required transverse aortic arch and thoracoabdominal aortic replacement.

Adult↗
PubMed1997

Leiomyosarcoma of the inferior vena cava: novel surgical reconstruction preserves renal function.

Leiomyosarcoma of the inferior vena cava is rare and to date 145 cases have been reported. Here a new case of primary leiomyosarcoma of the inter-renal vena cava is reported. Surgical treatment consisted of excision of the vena cava on top of the renal arteries allowing radical resection. Reconstruction was original. The distal vena cava was sectioned and ligated just above the bifurcation and the free segment used to replace the excised part. In this the right venal vein was directly implanted. The left renal vein was reimplanted in the translocated segment via a venous (femoral vein) graft. Ligation of the distal vena cava was haemodynamically well-tolerated and the patient was free of symptoms at one year after operation. Control angiogram showed patency of the venous reconstruction. Early diagnosis is essential to improve patient survival, since it allows better radical resection, which is the only way of preventing the development of metastases.

Hemodynamics↗
PubMed1997

[Value of carbon in the thrombogenicity of cardiovascular prostheses].

Forty five Carbon-lined (CL) and 45 Standard (ST) 4 mm internal diameter polytetrafluoroethylene (PTFE) grafts were implanted as aortic interpositions in 90 New Zealand rabbits. In a pilot study of 20 animals, 10 CL and 10 ST grafts were used to develop microsurgical techniques, then 60 grafts were placed in 60 rabbits with lower morbidity. The 2-hour graft patency (Doppler study, Transonic flow probe and 8 mHZ) showed a better patency rate in the CL group (93% versus 80%). In 10 animals, platelet accumulation was investigated in vivo using scintigraphy after injection of autologous platelets labeled with Indium111. In vitro, radioactivity counting of the explanted midgrafts sections at 2 hours revealed a 6-fold higher activity in ST grafts (6.60 +/- 1.98 x 103 platelets/mm2 versus 0.82 +/- 0.25 x 103 platelets/mm2; p < 0.05). Light microscopy found platelet and fibrin deposition (PFD) in nearly all ST grafts, whereas PFD were found in only 13% of the CL grafts corresponding to those thrombosed grafts (chi2:61.117; p < 0.001). Carbon-lining decreases platelet accumulation on PTFE grafts and the rabbit aortic interposition appears to constitute a quantitative and reproducible model for investigation of antithrombotic drugs.

Animals↗
PubMed1996

[Associated carotid and coronary lesions: carotid endoluminal angioplasty before coronary surgery].

OBJECTIVE: There is debate over the therapeutic strategy in patients with lesions of both the coronary arteries and the carotid arteries. Improvement in angioplasty techniques for the carotid artery would be a minimally invasive alternative. METHODS: Between January 1993 and June 1995, 12 patients who underwent endoluminal angioplasty of the carotid artery before coronary bypass surgery (mean 17.9 days before) were included in the study. Mean age was 70 +/- 3.2 years. The carotid lesions were asymptomatic in all patients who had stable angina. RESULTS: The mean number of bypasses was 2.9 per patient. Five patients had a contralateral stenosis of the internal carotid artery. Angioplasty was performed under cerebral protection using a three way coaxial catheter. A Strecker stent was required in 8 cases. One patient presented transient hemianopsia. All patients were seen again at 4 months for an angiogram then at 6 months for a Doppler examination. One patient needed complete redilatation with a stent and one other required dilatation of the stent. CONCLUSIONS: Endoluminal angioplasty of the carotid arteries gave encouraging results in this high-risk population (underlying disease, age, bilateral carotid lesions, arterial coronary grafts). This technique should be used more widely for patients with severe multiple arterial lesions.

Aged↗
PubMed1996

Operation for atrial septal defect through a right anterolateral thoracotomy: current outcome.

BACKGROUND: Operative closure of atrial septal defect is today considered a high-benefit and low-risk operation. Patients are often young and sensitive to the cosmetic results of the procedure. The midline scar of median sternotomy may be unsightly and can provoke dissatisfaction and psychological distress. For cosmetic reasons, an alternative operative approach, such as right anterolateral thoracotomy, can be proposed, with better aesthetic results and without increasing operative risks. METHODS: Our study reviews retrospectively the long-term results of a consecutive series of 56 young patients in whom the atrial septal defect was closed through a right submammary approach. The indication for this approach was isolated atrial septal defect in female patients with complete development of the breasts. RESULTS: In-hospital morbidity included three postpericardiotomy syndromes with one operative drainage for a moderate pericardial effusion (subxiphoid approach); 6 patients had supraventricular tachycardia in the early postoperative period. One patient presented with a symptomatic supraventricular arrhythmia and was treated medically for atrial flutter or fibrillation. Follow-up ranged from 12 to 240 months and included 41 of 57 patients. There were no early or late deaths. All patients were in normal sinus rhythm and free of symptoms, in New York Heart Association functional class I. Electrocardiography results showed 4 patients with first-degree atrioventricular block and 5 with complete right bundle branch block. Echocardiographic study results showed 3 patients with a trivial residual shunt. There were no other late complications. Breast volume and symmetry and the character of the scar were evaluated objectively by a physician and subjectively by a multiple-choice questionnaire completed by the same patients. The answers suggested that the patients' subjective impressions were at least commensurate with the objective findings. Most of the patients perceived the cosmetic results as good or excellent. No serious psychological problems related to the scar were found. CONCLUSIONS: Right thoracotomy incision is a safe alternative approach to median sternotomy to repair isolated atrial septal defect in young female patients.

Adolescent↗