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Recanalization of aged venous thrombotic occlusions with the aid of a rheolytic system: an experimental study.

PURPOSE: The suitability of a rheolytic system for recanalization of aged venous thrombotic occlusions was tested in an animal experiment. METHODS: The system consists of a flush-suction catheter and a high-pressure liquid pump. Thrombosis was experimentally induced in 13 venous segments of 10 adult goats. RESULTS: After a mean period of 12 days, a complete thrombectomy using the flush-suction system was achieved in 12 cases. No complications such as perforation or dissection were observed. CONCLUSION: This system seems to be an appropriate device for percutaneous transluminal venous thrombectomy, even in older occlusions.

Animals↗

[Anti-ischemic effect of verapamil within the scope of interventional recanalization].

We report on a 46-year-old male with unstable angina pectoris due to a total proximal occlusion of the left circumflex artery. At the side of a plaque rupture there was a thrombotic occlusion. With PTCA recanalization was possible, but a dissection occurred, therefore coronary stents were implanted. Besides an optimal morphological result and recurrent applications of nitroglycerin, the baseline blood flow velocity declined from initial 16 cm/s to 11 cm/s after PTCA down to 8.4 cm/s after stent implantation. Because peak flow velocity remained almost unchanged, the low baseline velocity ("slow flow phenomenon") did not lead to an impaired coronary flow velocity reserve (CFVR). Only after application of 1 mg verapamil, a sustained flow velocity on a higher baseline level was reached (17 cm/s), at the same time typical signs of ischemia in the ECG (ST-segment depressions) improved. Additionally, in the non-treated LAD there was an increase in coronary blood flow velocity from 10 cm/s up to 25 cm/s. The reduction in coronary blood flow velocity with increasing manipulations might be due to an impairment of the coronary microcirculations with increasing alpha-adrenergic vasoconstriction, a distribution of vasoactive agents and peripheral microembolizations. Only after administration of verapamil, a calcium channel blocker with non-specific anti-adrenergic effects, the slow flow was removed and ECG signs of ischemia improved. The blood flow velocity in the non-treated LAD was low at baseline and improved after verapamil. This phenomenon leads to the conclusion that mechanisms with vasoconstrictive effect are present in the whole coronary system, but these mechanisms are less pronounced in non-treated vessels.

Angina, Unstable↗

Successful recanalization of late portal vein thrombosis after liver transplantation using systemic low-dose recombinant tissue plasminogen activator.

Portal vein thrombosis (PVT) is an infrequent complication following hepatic transplantation. However, deterioration of liver function and accompanying complications may be life threatening. Several attempts of surgical or percutaneous transhepatic procedures have been described. In some cases high dose fibrinolytic regimens have been successful. We describe the case of a male liver recipient with recurrent liver fibrosis due to hepatitis B reinfection and late portal vein thrombosis 45 months after transplantation. Complete recanalization was achieved using systemic low dose recombinant tissue plasminogen activator (rt-PA).

Fibrinolytic Agents↗

Endovascular recanalization of acute atherothrombotic carotid artery occlusion holds up progressive stroke.

In acute carotid artery occlusion, hemodynamic compromise in addition to artery-artery thromboembolism is the mechanism of ischemia that may lead to a progressive clinical course with enlarging infarcts. The natural course of carotid artery occlusion with a progressive stroke is unfavorable with only about 10% of patients making a good recovery. We report on two patients in whom emergency recanalization of acute carotid artery occlusion with self-expanding stents restored cerebral blood flow and held up progressive stroke.

Carotid Artery Thrombosis↗

Percutaneous recanalization of peripheral arterial occlusions.

The aim of this paper is to summarize the current status of percutaneous methods for recanalizing peripheral arterial occlusions. Emphasis is placed on the role of peripheral intraarterial thrombolysis (PIAT) in the treatment of acute lower limb ischemia. Results of three prospective, randomized trials comparing PIAT with surgical revascularization are analyzed in the context of the existing, largely retrospective literature. The technique and recommendations for the application of PIAT are reviewed. Percutaneous aspiration thromboembolectomy, a technique that may be used alone or in conjunction with PIAT, is described in detail. We conclude with a brief description of various percutaneous mechanical thrombectomy devices, which may potentially see application in peripheral arterial occlusions.

Arterial Occlusive Diseases↗

Spontaneous recanalization of superior mesenteric artery occlusion following angioplasty and stenting of inferior mesenteric artery.

An 84-year-old woman with a history of hypertension and coronary artery disease was admitted with a progressively worsening diffuse abdominal pain. Computed tomography scan of the abdomen and angiography revealed occlusion of the origin and proximal portion of superior mesenteric artery. Aortography also showed severe origin stenosis of inferior mesenteric artery and that the distal part of the superior mesenteric artery was supplied by a prominent marginal artery of Drummond. Patient was effectively treated with percutaneous transluminal angioplasty and stenting of the inferior mesenteric artery. Follow-up imaging studies demonstrated patency of the stent and spontaneous recanalization of superior mesenteric artery occlusion.

Aged, 80 and over↗

Subintimal recanalization of long superficial femoral artery occlusions through the retrograde popliteal approach.

PURPOSE: To investigate the value of the retrograde popliteal artery approach for the percutaneous intentional extraluminal recanalization (PIER) of long superficial femoral artery (SFA) occlusions. METHODS: During a period of 17 months, PIER through ultrasound-guided retrograde popliteal artery puncture was performed for 39 long SFA occlusions in 37 patients. In six patients, six additional iliac artery stenoses were also treated via the popliteal approach. RESULTS: The procedure was technically successful in 32 (82%) of 39 SFA occlusions; in 29, lesions were treated with balloon angioplasty alone, and in three, stents were also used. Cumulative patency rate was 66% at 6 months, 62% at 1 year, and 59% at 18 months. Additional iliac artery stenoses were successfully treated in the same session. Complications included two minor hematomas and two SFA ruptures, which required no treatment. CONCLUSION: PIER through retrograde popliteal puncture is a safe and effective method in the treatment of long femoropopliteal occlusions, with a high technical success, low complication rate and a reasonable short-term patency rate. The technique offers an alternative in cases where standard PIER is unsuccessful or contraindicated.

Aged↗

Fluoroscopically guided transcervical fallopian tube recanalization of post-sterilization reversal mid-tubal obstructions.

PURPOSE: To assess the technical success and early outcome of fluoroscopically guided transcervical fallopian tube recanalization (FTR) in mid-tubal occlusion following sterilization reversal surgery. METHODS: From July 1995 to January 1998, patients with greater than 12 months secondary infertility underwent hysterosalpingography (HSG). FTR was performed in proximal or mid-tubal occlusion. Cases of FTR in mid-tubal occlusion were included in this study. Technical success (defined as complete tubal patency) using a standard guidewire and hydrophilic glidewire, the number of patients with at least one patent tube, and the intrauterine and ectopic pregnancy rates were determined. RESULTS: Twenty-six infertile patients with previous sterilization reversal underwent HSG. Eight of 26 (31%) patients (mean age 32 years, range 23-37 years), had attempted FTR for mid-tubal occlusion at the site of surgical anastomosis. Fourteen tubes were attempted as there were two previous salpingectomies. Technical success was achieved in eight of 14 (57%) tubes attempted, resulting in five of eight (62%) patients having at least one patent tube. At follow-up (mean 18 months, range 12-28 months) in these five patients there was one intrauterine pregnancy. There were no ectopic pregnancies. CONCLUSIONS: FTR in mid-tubal obstruction in infertile patients following sterilization reversal surgery is technically feasible and may result in intrauterine pregnancy. In this small group there was a lower technical success rate and lower pregnancy rate than in unselected proximal tubal occlusion.

Adult↗

Stent recanalization of chronic portal vein occlusion in a child.

An 8-year-old boy with a 21/2 year history of portal hypertension and repeated bleedings from esophageal varices, was referred for treatment. The 3.5-cm-long occlusion of the portal vein was passed and the channel created was stabilized with a balloon-expandable stent; a portosystemic stent-shunt was also created. The portosystemic shunt closed spontaneously within 1 month, while the recanalized segment of the portal vein remained open. The pressure gradient between the intrahepatic and extrahepatic portal vein branches dropped from 17 mmHg to 0 mmHg. The pressure in the portal vein dropped from 30 mmHg to 17 mmHg and the bleedings stopped. The next dilation of the stent was performed 12 months later due to an increased pressure gradient; the gastroesophageal varices disappeared completely. Further dilation of the stent was planned after 2, 4, and 6 years.

Catheterization↗

Use of a puncture needle for recanalization of an occluded right subclavian vein.

We report a patient in whom we used a puncture needle to initiate percutaneous recanalization of a chronic occlusion of the junction between the right subclavian vein and the right brachiocephalic vein. Under fluoroscopic guidance, an 18-gauge needle was used to puncture the right subclavian vein. When contrast material injected through the needle confirmed intravascular location, the needle was advanced until it deflected and perforated an occlusion balloon target positioned within the right brachiocephalic vein. This technique may be useful in patients with central venous occlusions that are refractory to traversal using traditional catheter and guidewire techniques.

Aged↗

Recanalization of a portal-vein thrombosis and partial resolution of biliary cirrhosis following cholecystectomy for cholelithiasis in an infant.

Cholelithiasis in infants and children is unusual and is reputedly associated with underlying hemolytic disorders, total parenteral nutrition, ileal disease, and congenital anomalies of the biliary tree. We report a case of cholecystitis with pigmented stones in a 3-month-old infant associated with portal vein thrombosis (PVT) and biliary cirrhosis without the above-mentioned causes. Recanalization of the PV and partial resolution of the cirrhosis was observed following cholecystectomy. To our knowledge, cholelithiasis associated with PVT and cirrhosis in an infant has not been reported in the literature.

Biopsy, Needle↗

[Coronary flow velocity reserve and collateral resistance after recanalization of chronic total coronary occlusions and periprocedural CK and cTNI elevation].

After recanalization and stenting of chronic total coronary occlusions (TCO), a reduced coronary flow velocity reserve (CFVR) and rise in collateral resistance (R(Coll)) is frequently observed. Coronary microembolization may account for these observations. In 86 patients (age 64+/-10 years; 77 men, 9 women) with TCO (duration >4 weeks), PTCA was performed with successful stent implantation in all lesions. Before PTCA, viable myocardium was detected by stress echocardiography or nuclear imaging techniques. By simultaneously measuring coronary Doppler flow velocity and pressure before and after PTCA, CFVR and R(Coll) were calculated. Over a period of 24 hours after intervention, creatine kinase (CK; upper limit of normal [ULN] for women 1.17 micromol/L/s, for men 1.33 micromol/L/s) and cardiac troponin I (cTNI; threshold 0.1 ng/mL) were studied. CFVR was <2 in 48% of all patients. A rise in R(Coll) was observed in 83% of all patients. The incidence of CK and/or cTNI elevation was only observed in 10% of all patients. These patients with CK and/or cTNI elevation did not show a significant difference of CFVR and rise in R(Coll) as compared with patients without CK and cTNI elevation. CFVR or rise in R(Coll) did not correlate with CK elevation. Coronary microembolization is not a likely cause of reduced CFVR and increased R(Coll) after PTCA of TCO. Other factors such as microvascular dysfunction and autoregulatory changes in collateral function may account for these observations.

Aged↗

[Recanalization of Botalli's ductus arteriosus after catheter occlusion with a Rashkind double umbrella device].

Interventional duct occlusion with the Rashkind PDA occluder has become a widespread alternative treatment to surgery. Whereas residual shunting is well-known, reopening of a completely occluded duct has been published in only 3 cases. We report another case of a young adult in whom ductal shunting reappeared after he had restarted physical exercise and sports activities soon after the occlusion procedure. Recanalization might have been due to changing of the device position without embolisation. A second Rashkind PDA occluder was successfully implanted 6 months after the first procedure with complete closure of the residual shunt.

Adult↗

[Intracoronary ultrasound during recanalization of chronic coronary occlusions: Relation to restenosis and reocclusion after balloon angioplasty or stent implantation].

Chronic coronary occlusions carry a high recurrence rate, and coronary stenting evolves as a preferred therapy of these complex lesions. Insight into the morphology of the occluded segment by intracoronary ultrasound may provide information which may help to improve the interventional strategy and the long-term outcome. After successful recanalization of chronic coronary occlusions (4 weeks to 33 months; median 3.2 months) in 59 patients, 29 patients were treated by balloon angioplasty alone, and 30 patients received one or more coronary stents because of complicated dissections or a high-grade residual stenosis after balloon dilatation. Intracoronary ultrasound was used to assess the lesion morphology and to quantify the angioplasty result. The luminal area, the total vessel area and the extent of the plaque burden were measured proximal and distal to the occlusion and at the narrowest site within the occlusion or the coronary stents, and the elastic recoil was calculated. Plaques in chronic occlusions were predominantly hypodense, and 44% were characterized by a multilayered plaque appearance. The elastic recoil was higher in multilayered plaques than in other plaques (46 +/- 19% vs. 34 +/- 15%; p < 0.05). Based on the quantitative ultrasound measurement after the initial balloon dilatation, it appeared that the initial balloon was undersized in 54%. The lumen area in patients with balloon angioplasty alone was increased from 4.02 +/- 1.34 mm2 to 5.49 +/- 1.47 mm2 and in the stented patients from 3.58 +/- 1.04 mm2 to 7.10 +/- 1.92 mm2. The recurrence rate in patients with balloon angioplasty was 48% with 24% reocclusions. Patients with recurrence had a slightly lower lesion area (3.97 +/- 1.41 mm2 vs. 4.71 +/- 1.44 mm2; n.s.) and minimum diameter (1.82 +/- 0.31 mm vs. 2.14 +/- 0.40 mm; p < 0.05) after dilatation. In stented patients the recurrence rate was 27% with two early stent thrombosis (6.7%) and no late reocclusion. In patients with recurrence the achieved stent area was significantly smaller than in those without restenosis (5.71 +/- 0.90 mm2 vs. 7.59 +/- 1.96 mm2; p < 0.01), and the degree of vascular remodelling at the site of the occlusion was less pronounced. Intracoronary ultrasound showed sonographic plaque characteristics in chronic occlusions which responded poorly to balloon dilatation alone. Stent implantation improved considerably the luminal area gain and could reduce the long-term outcome. To further improve the recurrence rate in stents, an optimized stent expansion should be achieved, and intracoronary ultrasound could provide an ideal tool for this purpose.

Aged↗

[Heparin-induced thrombocytopenia type II with early aortocoronary bypass occlusion and stent thrombosis after PTCA of the RCA--treatment with lepirudin (Refludan) and abciximab (Reo pro) during recanalization of the RCA].

Heparin-induced thrombocytopenia type II (HIT type II) is the most serious complication of heparin treatment apart from bleeding, which is the most common side effect. Eleven days after coronary bypass grafting, a 71 year old patient showed a posterolateral myocardial infarction and a thrombocytopenia of 80,000/microliter. This was considered a postoperative thrombocytopenia. Coronary angiography revealed closed venous bypass grafts. The right coronary artery (RCA) was revascularized by percutaneous transluminal coronary angioplasty (PTCA) and stent placement. During both coronary angiography and PTCA, heparin was administered to the patient. The platelet number did not change. Four days later the patient showed an inferior myocardial infarction and an AV-block III degrees and a syncope. The following coronary angiography revealed RCA stent occlusion. HIT type II was presumed and recanalization was carried out using Lepirudin (Refludan) as the anticoagulant. After placing the guide wire, thrombi could be seen in the proximal RCA. Abciximab (Reo pro), a monoclonal antibody against the glycoprotein IIb/IIIa receptor was additionally administered. Coronary angiography on the next day revealed only a small remaining thrombus. The AV-block disappeared immediately after revascularization. The diagnosis of HIT type II was confirmed through heparin-induced-platelet-activation-test (Hipa-test) and immunoassay (PF 4/heparin-ELISA). This case report illustrates the complicated diagnosis of HIT type II and the successful simultaneous use of Lepirudin (Refludan) and Abciximab (Reo pro). The number of platelets should be checked daily during heparin treatment. In the case of a thrombocytopenia, the treatment should be stopped immediately, and Hipa-test and PF 4/heparin-ELISA should be carried out.

Abciximab↗

Impaired coronary flow and left ventricular dysfunction after mechanical recanalization in acute myocardial infarction: role of neurohumoral activation?

BACKGROUND: Reopening of the infarct-related coronary artery is the treatment of choice in the clinical setting of acute myocardial infarction. Nevertheless the removal of the total occlusion obtained either by thrombolysis or by primary angioplasty is followed by the ischemia/reperfusion sequelae. One of many proposed mechanisms playing a role in ischemia/reperfusion damage is a persistent increase in vasoconstrictor tone, which reduces cardiac function and impairs myocardial blood flow during primary percutaneous coronary intervention in acute myocardial infarction (PAMI). METHODS: To investigate early neurohumoral changes during PAMI we enrolled 18 patients, who were collated to 13 patients with stable angina undergoing elective PTCA. To evaluate angiotensin II (AngII), endothelin-1 (ET-1), vasopressin (AVP), norepinephrine (NE), troponin T (TNT), creatinephosphate kinase (CPKM) and isoenzyme MB (CPKMB), we collected blood from the pulmonary artery before and immediately after the infarct-related artery (IRA; TIMI 0 --> 2-3) or culprit lesion revascularization. Hemodynamic and angiographic LV-function parameters were compared to biochemical data. Corrected TIMI-frame count (CTFC) was used as an index of coronary blood flow and correlated to the biochemical measurements. RESULTS: CTFC in the IRA correlated inversely (p = 0.03; r = -0.51) with left ventricular ejection fraction measured after 10 days, and positively (p = 0.03; r = 0.54) with the maximal amount of LDH released after onset of AMI. There was an abrupt and long lasting rise in ET-1 (+65 %; p < 0.001) and an instant short lasting increase in AVP (+37 %; p < 0.05), whereas NE concentrations were elevated prior to PAMI and remained elevated during reperfusion. Correlations with CTFC were found for ET-1 (p = 0.01; r = 0.61) and NE (p = 0.01; r = 0.58) during reperfusion. The extent of left ventricular dysfunction correlated with the concentrations of AVP and NE during reperfusion. CONCLUSIONS: There is evidence for a distinct pattern of neurohumoral activation during early reperfusion in acute myocardial infarction. In particular, we documented substantial increases in AVP and ET-1. Left ventricular wall-stress appears to be involved in the release of AVP. Elevated levels of ET-1 and NE are associated with impaired angiographic reperfusion and increased myocardial damage after mechanical recanalization.

Aged↗

Post-transplant IVC occlusion and thrombosis treated with tPA, heparin, and sharp recanalization.

Complete inferior vena cava (IVC) thrombosis can be a lethal complication in a liver transplant recipient. The case of a 52-year-old liver transplant recipient, who developed complete IVC as well as left iliofemoral thrombosis, is reported. After treatment with combined tissue plasminogen activator (tPA) and heparin, the IVC was successfully recanalized with sharp dissection, balloon dilatation, and stent placement.

Blood Vessel Prosthesis Implantation↗

Recanalization of an occluded popliteal artery following posterior knee dislocation.

Posterior knee dislocation results in popliteal artery injury in up to one-third of cases. Prompt recognition and treatment of arterial injury is essential for limb salvage. We report a case of complete occlusion of the popliteal artery following posterior knee dislocation treated with saphenous vein bypass without exclusion of the injured arterial segment. Follow-up duplex scanning demonstrated a patent vein graft and a patent ipsilateral popliteal artery. This report suggests that, in some instances, a traumatically occluded popliteal artery may recanalize, and that revascularization with a bypass graft may be the preferred method of repair, particularly in young patients.

Child↗