Antonio Mainar

New procedure for the treatment of colorectal neoplastic obstructions.

PURPOSE: A new procedure for the treatment of colorectal neoplastic obstructions is described. METHODS: This procedure involves the following phases: 1) placing a stent at the point of the stenosis of the colon, which enables the acute obstruction phase to be overcome; 2) recovering the general state of the patient, analyzing the development of the disease, and mechanically preparing the colon; 3) performing regulated and final surgery. RESULTS: In two patients, these three phases have been completed without complication and with excellent results. CONCLUSION: This procedure is both safe and effective and could become the method of choice for the treatment of colorectal neoplastic obstructions.

Initial results of a new procedure for treatment of malignant obstruction of the left colon

PURPOSE: This study was undertaken to analyze the results obtained in 38 unselected patients using a new and original procedure for treatment of malignant obstructions of the left colon. METHOD: This procedure involves three phases: 1) resolution of the obstruction by means of a stem placed at the site of the tumor; 2) recovery of the general state of the patient, study of the extent of disease, and mechanical preparation of the colon; 3) regulated and final surgery (if this is not suitable, the stent may be used as definitive palliative treatment). RESULTS: In 35 patients (92 percent), the obstruction was resolved with the stent. In 22 patients the three phases were completed, and in 13 patients the stent constituted definitive palliative treatment. Only one patient (2.6 percent) died after resection of the tumor. CONCLUSION: This procedure offers a new, safe, and efficacious option for treatment of neoplastic colorectal obstructions.

The Günther Tulip Retrievable Filter: Prolonged Temporary Filtration by Repositioning within the Inferior Vena Cava

PURPOSE To report experience with the retrievable Günther Tulip filter (GTF) as a means of temporary caval filtration for the prevention of pulmonary embolism (PE) with use of a technique that prolongs filter dwell time beyond 14 days. MATERIALS AND METHODS Eighty-eight GTFs were implanted in 87 patients. The GTFs were placed with the intention of retrieval in all patients within 14 days after initial implantation. In 23 of the 87 patients (26%), there was a need to prolong temporary caval filtration beyond the recommended period of 14 days. This was successfully achieved with use of percutaneous techniques from the right internal jugular vein whereby the filter was repositioned to a different location within the inferior vena cava (IVC) before definitive device removal. RESULTS Of 88 GTFs implanted in 87 patients, 70 were successfully retrieved and 18 were left in place permanently. Forty-seven filters in 46 patients were removed after initial implantation with no need for percutaneous repositioning within the IVC to prolong dwell time (mean dwell time, 13 days). In the 23 patients who required repositioning of 23 GTFs within the IVC to prolong temporary caval filtration, the mean dwell time was 34.8 days; the mean number of repositioning procedures was 1.5, the mean time between repositioning procedures was 13.8 days, and the mean fluoroscopy time was 4.4 minutes in patients in whom filter retrieval was attempted. One patient underwent placement and subsequent removal of the GTF twice for perioperative prophylaxis against PE on two separate occasions. No filters were misplaced in an unintended location or tilted (>15 degrees ) in relation to the main caval axis after deployment. In one patient, a GTF became permanently fixed in the IVC 16 days after initial implantation and could not be removed percutaneously. Nine patients had mild or moderate-sized cervical hematomas. One patient had recurrent asymptomatic PE 2 months after filter insertion. CONCLUSION Dwell times of 14 days can be achieved in most patients before device removal. Prolongation of the dwell time beyond 14 days can be safely and easily achieved by performing percutaneous repositioning of the device within the IVC via a jugular approach.

Mechanical and Enzymatic Thrombolysis for Massive Pulmonary Embolism

PURPOSE To assess the efficacy and safety of mechanical fragmentation combined with intrapulmonary thrombolysis in massive pulmonary thromboembolism (PTE) with hemodynamic impairment. MATERIALS AND METHODS Fifty-nine patients diagnosed with massive PTE with hemodynamic impact were treated. The initial clinical symptoms were shock in 23 patients (38.9%), syncope in eight (13.5%), and dyspnea at rest in 28 (47.4%). Mean O2 saturation was 67.8%. Mean pulmonary artery pressure (PAP) was 42.1 mm Hg. During fragmentation, thrombolysis was administered in the form of a urokinase bolus of 200,000-500,000 U in 57 patients and 20 mg of recombinant tissue plasminogen activator (rt-PA) in two patients. The mean urokinase dose used was 2,500,000 IU, whereas the total dose of rt-PA was 100 mg. Heparin sodium infusion was performed to reach activated partial thromboplastin time ratios of 2. The follow-up consisted of clinical assessment, pulmonary scintigraphy, and echocardiography. The patients received treatment with dicoumarin for 6 months after the procedure. RESULTS Clinical improvement was seen in 56 patients (94%). Three patients died. The mean PAP after the treatment was 21.8 mm Hg. The mean posttreatment Miller index was 0.35. Technical success was achieved in all cases and clinical symptoms improved in all cases except those in which the patients died. Pulmonary scintigraphy showed improved perfusion in all cases. Echocardiography was performed after 3-6 months, showing a mean pressure of 22.8 mm Hg (corrected values). There were no signs of recurrent PTE or arterial hypertension in the follow-up. CONCLUSION The data provided confirm the efficacy and safety of mechanical fragmentation and pharmacologic thrombolysis in the treatment of massive PTE with hemodynamic impairment, showing improvement of symptoms and a decrease in PAP.

Animal experience in the Günther Tulip retrievable inferior vena cava filter.

AbstractPurpose: To assess the retrievability of the Gunther Tulip temporary inferior vena cava filter from a technical viewpoint, and consider the histopathologic changes that occur at the anchoring site of the filter prongs to the vein endothelium in Landrace pigs. Methods: Twenty-two Gunther Tulip retrievable filters were inserted in 22 experimental Landrace pigs via the jugular vein. Device implantation time was 0, 3, 7, 12, 14, 15, 16, 20, 30, 35 and 56 days. Study subjects were divided into two groups. In one group the filter was retrieved percutaneously via the jugular vein whereas in the other group it was removed surgically. The specimens obtained (vena cava and filter) were histopathologically examined. Prior to filter retrieval, a venacavography was obtained in all cases. Degree of retrieval difficulty was rated as follows: no difficulty (N), slight (S), mild (M), high (H) and unretrievable (U). Results: Of the 22 implanted filters, 11 should have been removed percutaneously but this was impossible in three cases (U). In four cases the device was retrieved with no difficulty (N); in two cases the degree of difficulty was mild (M) and in other two it was high (H) and slight (S) respectively. Retrieval difficulties were observed after 16 days. Starting from day 20, there was evidence of fibrosis with thick intimal proliferation and total filter prong involvement, which accounts for the difficulty in retrieving the device. Conclusions: It is advisable not to exceed a filter retrieval time of 16 days in view of the fibrotic changes reported. It might be necessary to perform a larger study with more animals and with retrieval times between 14 and 20 days.

Retrieval of Gunther Tulip optional vena cava filters 30 days after implantation: a prospective clinical study.

PURPOSE To report on the feasibility and safety of retrieval of the Günther Tulip optional vena cava filter 30 days after initial implantation. MATERIALS AND METHODS From March 2004 to September 2005, a single-center prospective study was undertaken in 35 patients who required inferior vena cava (IVC) filtration. All the Günther Tulip filters (GTFs) were implanted with the intention to be removed 30 days after initial implantation. A modified commercial dynamometer was used to measure the force required to remove the device. The degree of difficulty to remove the GTF was classified into four levels: N (no difficulty, force of 0-4.41 N), M (medium difficulty, force of 4.41-5.88 N), G (great difficulty, force of 5.88-9.8 N), and U (unable to remove). Clinical follow-up was performed 1, 3, 6, and 12 months after filter retrieval by review of medical records and imaging. RESULTS Two of the 35 patients experienced extensive thrombosis in the IVC as revealed by abdominal computed tomography, and their filters were left in place on a permanent basis. One patient died of respiratory and cardiac failure during follow-up within the first 30 days after GTF insertion. Filter retrieval was attempted in the remaining 32 patients, and 31 of these attempts were successful (98%). The force necessary to disengage the GTF from the caval wall was less than 9.8 N (N, 79%; M, 13%; G, 6%). Attempts to remove the GTF failed in only one patient (2%). On follow-up times ranging between 14 and 640 days (mean, 342.5 d), no complications or cases of recurrent pulmonary embolism were observed in this patient population. CONCLUSION The Günther Tulip optional IVC filter can be safely placed and retrieved percutaneously 30 days after initial implantation.

Endovascular Treatment of Massive Hemoptysis by Bronchial Artery Embolization: Short-Term and Long-Term Follow-Up Over a 15-Year Period

OBJECTIVE To present our experience of using arterial embolization for the endovascular treatment of massive hemoptysis along with the results of follow-up over a 15-year period. PATIENTS AND METHODS A total of 401 patients with hemoptysis were referred to the minimally invasive surgery unit of the Hospital Universitario Lozano Blesa de Zaragoza between April 1989 and September 2004 for diagnosis and possible endovascular treatment. Of those patients, 314 met criteria for massive hemoptysis and treatment was attempted using embolization in 287 (91.4%). The most common cause of hemoptysis was bronchiectasis (n=99, 31.5%), followed by lesions due to tuberculosis (n=57, 18.1%) and chronic bronchitis (n=47, 14.9%). RESULTS Angiography of the bronchial arteries provided evidence to account for the hemoptysis in 287 patients (91.4%). The affected arteries were satisfactorily embolized in 281 (97.9%). Endovascular treatment was clinically successful in 256 of those patients (91.1%). Embolization had to be repeated during the hospital stay in 19 patients (6.7%) and was effective in 52.6% of those cases. The 6 patients in whom embolization was not satisfactory underwent thoracotomy. The mean follow-up in 201 patients (71.5%) was 2372.5 days (range, 61-5475 days). Eighty patients (28.4%) were lost to follow-up for various reasons and at different points. Recurrence of hemoptysis occurred on 1 or more occasions in 45 patients (22.3%) but only 21 (10.4%) required repeat embolization. Minor complications that did not require treatment were observed in 88 patients (28.0%). CONCLUSIONS Embolization of bronchial arteries is a nonsurgical treatment that is safe and effective in patients with massive hemoptysis.

Colon Stenting: A Review

Up to 85% of patients who present with colonic obstruction have a colorectal cancer. Between 7% and 29% of these patients present with total or partial intestinal obstruction. Only 20% of these patients presenting with acute colonic obstruction due to malignancy survive 5 years. Emergent surgical intervention in patients with colonic obstruction is associated with significant morbidity and mortality rates. Only 40% of patients with obstructive carcinoma of the left colon can be treated with surgical resection without the need for a colostomy. The use of a temporary or permanent colostomy has a significant impact on quality of life. The decompressive effect seen with colonic stenting is a durable, simple, and effective palliative treatment of patients with advanced disease. Stent deployment provides an effective solution to acute colonic obstruction and allows surgical treatment of the patient in an elective and more favorable condition. In addition, colonic stenting reduces costs and avoids the need for a colostomy.

Use of an introducer sheath for colonic stent placement

Abstract. We describe a technical modification of Wallstent implantation for the treatment of malignant rectosigmoid and descending colonic obstructions. The modification is the routine placement of an introducer sheath via the rectum before stent implantation in order to straighten the rectosigmoid region. This device facilitates catheter and guide wire manipulations and obtaining specimen biopsies for histopathological studies. The introducer sheath has been used without complications in 21 consecutive patients.

Seguimiento clínico y por medios de imagen a largo plazo de los filtros de vena cava inferior. Estudio transversal

Hemos realizado un estudio transversal con el fin de evaluar los hallazgos morfologicos, incidencias y complicaciones observadas en 77 filtros de vena cava inferior implantados en 75 pacientes desde abril de 1990 hasta enero de 1994. El tiempo de seguimiento de los pacientes oscilo entre los 3 y los 61 meses (media, 38,5 meses), realizando encuesta telefonica, evaluacion clinica, iliocavografia y, en algunos casos, ecografia-Doppler y tomografia computarizada (TC). Los hallazgos observados demostraron trombosis de vena cava en el 38% de los casos, edemas en EE1I en el 63,4% de los casos, angulacion > 15° en 8 pacientes, defecto de apertura en 4 pacientes, fibrosis de vena cava con estenosis en 2 casos y perforacion de vena cava inferior en 3 pacientes. Segun nuestro estudio si bien la incidencia de la trombosis de VCI posfiltro es mas alta que la sospechada habitualmente, la trascendencia clinica resulta irrelevante.