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PubMed1996

Effect of late percutaneous angioplastic recanalization of total coronary artery occlusion on left ventricular remodeling, ejection fraction, and regional wall motion.

The clinical benefit of late recanalization of complete coronary occlusion is debated. Left ventricular (LV) function and volumes are major prognostic determinants in patients with coronary artery disease. We sought to assess comprehensively the evolution of global and regional LV function and LV volumes after percutaneous recanalization of chronic complete coronary artery occlusions. A consecutive series of 55 patients who underwent successful percutaneous recanalization of a chronic (> or = 10 days), total (Thrombolysis in Myocardial Infarction trial flow grade 0) occlusion of the left anterior descending or dominant right coronary arteries, and in whom a complete angiographic evaluation was available before angioplasty and at follow-up was studied. At follow-up, 38 patients had a patent artery (group 1) and 17 had a reocclusion (group 2). Baseline parameters were similar in the 2 groups. In group 1, LV ejection fraction increased from 55 +/- 14% to 62 +/- 13% (p <0.001), with an increase in fractional shortening in the occluded artery territory (0.43 +/- 0.30 to 0.71 +/- 0.34, p <0.001), while LV end-diastolic volume remained unchanged. In group 2, ejection fraction and regional wall motion were unchanged, while LV end-diastolic volume index increased (86 +/- 22 ml/m2 to 99 +/- 34 ml/m2, p <0.02). The evolution in LV global and regional function was similar in patients with or without previous myocardial infarction; however, prevention of LV remodeling was observed only in patients with previous infarction. Maintained potency after successful recanalization of totally occluded coronary arteries improves global and regional LV function and, in patients with previous myocardial infarction, avoids LV remodeling.

Aged↗
PubMed1991

Fallopian tube catheterization and recanalization under ultrasonic observation: a simplified technique to evaluate tubal patency and open proximally obstructed tubes.

OBJECTIVE: To test a sonoscopic technique developed for transvaginal catheterization and recanalization of the fallopian tube. DESIGN: In a feasibility study, catheterization was performed with the use of laparoscopic control. Patients with bilateral proximal tubal obstruction underwent fallopian tube recanalization under ultrasonic observation. SETTING: This study represents patients evaluated for primary or secondary infertility at Humboldt University Hospital. PATIENTS, PARTICIPANTS: Proximal tubal obstruction had been diagnosed on previous hysterosalpingogram and with laparoscopy. INTERVENTIONS: None. MAIN OUTCOME MEASURE: Tubal patency was assessed by hydrotubation under ultrasonic observation. RESULTS: Transvaginal catheterization was successful in 31 (91.2%) of the 34 tubes. In 19 patients with proximal tubal obstruction, patency of both or at least one tube was achieved in 16 (84.2%) women. Five (31.6%) of 16 patients successfully recanalized were found to have an intrauterine pregnancy at a 6-month follow-up interval. CONCLUSION: This catheterization technique should be investigated for possible use in diagnostic schedule early in the evaluation of the infertile patient. Also, the transvaginal recanalization of proximally obstructed tubes calls into question the application of microsurgical treatment of a selected group of patients.

Adult↗
PubMed1999

Antegrade recanalization of completely embolized internal carotid artery after treatment of a giant intracavernous aneurysm: a case report.

BACKGROUND: Parent artery occlusion is one of the traditional methods of treatment for unclippable aneurysms. However, parent artery occlusion may not result in permanent exclusion of the aneurysm from the systemic circulation. We present a case of cerebral aneurysm treated by proximal embolization of the parent artery, which recanalized during the follow-up period. CASE DESCRIPTION: A 69-year-old woman presented with a right blepharoptosis and diplopia. A large aneurysm arising from the cavernous portion of the right internal carotid artery was found and endovascularly excluded from the cerebral circulation by proximal internal carotid artery occlusion with balloons. Eleven days after treatment, occlusion of the parent artery and obliteration of the aneurysm were angiographically confirmed. However, the parent artery was found to be recanalized with nearly total obliteration of the aneurysm at the follow-up 6 months after treatment. CONCLUSION: Angiography suggested that recanalization took place through the vaso vasorum. We believe that recanalization was induced by marginal cerebral blood flow in the ipsilateral hemisphere.

Aged↗
PubMed1997

Short-term results and intermediate-term follow-up of laser wire recanalization of chronic coronary artery occlusions: a single-center experience.

OBJECTIVES: This study sought to elucidate the short-term efficacy and intermediate-term outcome of excimer laser recanalization of chronic coronary artery occlusions in patients in whom attempts at mechanical revascularization had failed. BACKGROUND: Recanalization of chronic coronary occlusions with the use of a mechanical guide wire fails in 30% to 50% of cases, mostly because of inability to pass the wire through the lesion. The value of using excimer laser energy in this setting has not yet been determined. METHODS: The study group comprised 66 consecutive patients with 68 chronic coronary occlusions. Patients were eligible for inclusion in the study if a previous attempt at mechanical revascularization had failed and if their angiographic status was such that 1) the vessel segment distal to the occlusion could be visualized by way of collateral vessels, 2) the entry point of the occlusion was clearly outlined, and 3) not more than one anatomic bend was expected within the occlusion. Excimer laser energy was applied to the lesion through a 0.018-in. (0.046 cm) fiber-optic guide wire. Adjunctive balloon angioplasty and stenting were performed in all successfully treated patients but one. RESULTS: Thirty-four occlusions (50%) in 32 patients (48%) could be crossed with the laser wire. Location and age of the occlusion had no adverse influence on the outcome of laser wire recanalization, nor did the presence of bridging collateral vessels, a major side branch at the site of the lesion or a blunt stump of the occlusion. An inverse relation was found between the success rate and the length of the occlusion, such that a 19% reduction of the success rate accompanied each 10-mm increment of the mean occlusion length. Thus, the success rate was 68% for lesions < or = 10 mm but only 25% for lesions > 30 to < or = 40 mm. The presence of a bend in the lesion exceeding 60 degrees was strongly related to procedural failure. During a median angiographic follow-up period of 18 weeks, restenosis > 50% (n = 6) or reocclusion (n = 4) was found in 10 of the 32 successfully treated patients, for an intermediate-term success rate of 33% (22 of 66). Clinical follow-up revealed improved anginal status in 21 patients (66%) after a median of 24 weeks. Major complications (death, myocardial infarction, emergency operation) were not encountered. CONCLUSIONS: Successful recanalization of a chronic coronary occlusion by using currently available laser wires can be expected in 50% of selected patients in whom attempts at mechanical revascularization fail. Restenosis or reocclusion accounts for an overall 6-month success rate of 35%.

Angioplasty, Balloon, Coronary↗
PubMed1998

Prediction of short- and intermediate-term prognoses of patients with acute myocardial infarction using myocardial contrast echocardiography one day after recanalization.

OBJECTIVES: This study sought to determine whether microvascular integrity in the risk area (RA) for myocardial infarction (MI) one day after recanalization predicts the outcome in patients with first acute MI. BACKGROUND: Immediately after recanalization, microcirculation in the RA is modified by both hyperemic response and microvascular impairment. METHODS: Fifty consecutive patients who underwent serial myocardial contrast echocardiography before and one day after recanalization (day 2) were studied. All patients had a completely occluded lesion in the left anterior descending coronary artery alone, and underwent successful reperfusion therapy. The relative size of the initial RA (RA ratio) and peak gray scale ratio (PGSR) within the RA on day 2 were determined. Patients were followed for a median of 22 months to evaluate clinical outcome. RESULTS: On day 2, PGSR was a median of 0.46. Study patients were subdivided into two groups, group A of 24 patients with acceptable opacification (PGSR > 0.46 on day 2) and group B of 26 patients without it. Major cardiac events (cardiac death, nonfatal MI and repeat admission for congestive heart failure) were more frequently observed in group B (28% vs. 4%, Cox hazard ratio=8.5, p=0.05, 95% confidence interval [CI] 1.03 to 69.9). The median value of the RA ratio was 0.45. Patients (n=15) with RA ratio > 0.45 on day 1 and PGSR on day 2 < or = 0.46 exhibited a 10.7-fold relative risk for major cardiac events (p=0.005, 95% CI 2.06 to 55.8) and a 3.69-fold relative risk for composite cardiac events (major cardiac events and target lesion revascularizations) after the initial intervention (p=0.004, 95% CI 1.51 to 9.04). CONCLUSIONS: The assessment of both the size of the initial RA and microvascular integrity on day 2 enables precise determination of the efficacy of reperfusion therapy and prediction of the short- and intermediate-term prognoses of patients with recanalized MI.

Adult↗
PubMed1998

In vivo analysis of antithrombotic effectiveness of recombinant hirudin on microvascular thrombus formation and recanalization.

PURPOSE: This study was undertaken to evaluate in vivo the effect of recombinant hirudin (r-hirudin [HBW 023]), a potent thrombin inhibitor, on the process of microvascular thrombus formation and recanalization. METHODS: Thrombosis was induced photochemically in distinct arterioles (n = 25) and venules (n = 30) of the ear of 16 hairless hr/hr mice (8 to 10 weeks old, 25 to 30 g of body weight). r-Hirudin (1 mg/kg of body weight) was administered intravenously directly before thrombus induction; saline-treated animals served as controls. Thrombus formation (i.e., first platelet deposition at the endothelial lining [FPD]; inner luminal diameter reduction to 50% [D/2]; complete vessel occlusion [CVO]), vessel recanalization, microcirculatory parameters, and leukocyte-endothelial cell interaction were analyzed by means of intravital fluorescence microscopy. RESULTS: Hirudin significantly delayed the process of thrombus formation compared with saline-treated controls in both arterioles (FPD: 381 +/- 80 vs 137 +/- 25 seconds, P < 0.05; D/2: 627 +/- 49 vs 501 +/- 71 seconds; CVO: 925 +/- 78 vs 854 +/- 60 seconds) and venules (FPD: 173 +/- 11 vs 59 +/- 4 seconds; D/2: 342 +/- 54 vs 228 +/- 27 seconds; CVO: 541 +/- 85 vs 344 +/- 43 seconds; P < 0.05). In addition, r-hirudin-treated animals showed an increased rate of vessel recanalization at 24 hours after thrombus induction (arterioles: 54% [7 of 13] vs 0% [0 of 12], P < 0.05; venules: 77% [10 of 13] vs 53% [9 of 17]), whereas microcirculatory parameters and leukocyte-endothelial cell interaction were not affected. CONCLUSION: Our data indicate that r-hirudin not only counteracts the process of thrombus formation but also promotes vessel recanalization, thus supporting its use in clinical microvascular surgery.

Animals↗
PubMed1995

Transluminal recanalization of occluded iliac arteries: a surgical experience.

The purpose of this study was to evaluate the feasibility of transluminal techniques in an unselected group of patients and to assess long-term outcome in successful procedures. All patients in whom iliac artery recanalization was attempted were included in this study. Patients with an occluded prosthesis or recent embolism were excluded. A total of 37 patients were studied. Assessment of the success or failure of the procedure was based on the results of control arteriography. Recanalization was deemed successful in 31 patients. This study demonstrates that transluminal recanalization of occluded iliac arteries by a surgeon is indeed feasible. Primary patency was 66% at 24 months. The potential risk, however, is long-term restenosis. Thus follow-up examination every 6 months is recommended including pressure index measurements after exercise and color Doppler ultrasonography of the recanalized zone.

Adult↗
PubMed2003

Role of blood mononuclear cells in recanalization and vascularization of thrombi: past, present, and future.

Recent experimental data suggest a role for blood-borne mononuclear cells, including bone marrow-derived endothelial progenitor cells (EPCs) in organization, vascularization, and recanalization of thrombi. Older studies have described in detail the in situ structural modifications accompanying these processes. The common themes are (a) involvement of pluripotent mononuclear cells, and (b) proteolytic and/or phagocytic activity of monocytes/macrophages (MCs/Mphs) in modifying the thrombus to a proangiogenic state. In addition to a nurturing function, MCs/Mphs may assist the engraftment of thrombus-trapped or incoming EPCs. The differences between the recanalization potency of venous and arterial thrombi suggest that in addition to the organization of the fibrin meshwork, the cellular composition of the venous thrombi may be responsible for the better recanalization seen in venous clots. These observations set the stage for therapeutic manipulation of organization and recanalization of thrombi, by increasing the MC/Mph and/or EPC content.

Animals↗
PubMedDate not supplied

Recanalization of femoropopliteal occlusive lesions: a comparison of long-term clinical, color duplex US, and arteriographic follow-up.

PURPOSE: To assess the merits of clinical examination, color-flow duplex ultrasound (US), and arteriography in the follow-up of patients who have undergone femoropopliteal artery recanalization for occlusive disease. PATIENTS AND METHODS: Recanalization of the occluded femoropopliteal artery was attempted in 62 patients. Follow- up included clinical examination, ankle-brachial blood pressure measurement, and duplex US scanning at 4-month intervals during the first year, at 6-month intervals during the second year, and one a year thereafter. Failure of recanalization included substantial restenosis or reocclusion of the treated segment. Arteriography was performed at the end of the first year or earlier if recurrence was suspected. Agreement of clinical findings with those of duplex US and those of arteriography was determined with kappa statistics; a kappa value of greater than 0.75 represented excellent agreement. RESULTS: Recanalization was technically successful in 51 patients (82%). Clinical patency was 63% (standard error [SE], 6%) after 1 year, 56% (SE, 7%) after 2 years, and 46% (SE, 9%) after 3 years. When technical failures were included, the patency rate at duplex US was 58% (SE, 6%) after 1 year, 40% (SE, 7%) after 2 years, and 33% (SE, 8%) after 3 years. The patency rate at arteriography was 53% (SE, 7%) after 1 year, 33% (SE, 7%) after 2 years, and 30% (SE, 8%) after 3 years. When arteriographic examination was considered the standard of reference, diagnostic accuracy in the identification of recurrent lesions was 94% at duplex US (kappa = 0.88) and 74% at clinical examination (kappa = 0.51). CONCLUSION: Rates of restenosis or occlusion detected at follow-up with duplex US and arteriography were comparable. However, clinical examination alone helped detect fewer cases of recurrent disease.

Aged↗
PubMedDate not supplied

Teflon buttress inhibits recanalization of uncut stapled bowel.

The uncut Roux limb operation is designed to have the benefits of a Roux limb but still have electrical continuity from proximal to distal bowel, thus eliminating the risk of Roux stasis syndrome. The main complication has been recanalization of the uncut staple line leading to bile reflux. This study aims to employ a new technique, which will not allow recanalization of an uncut staple line but will not interfere with normal bowel myoelectric activity. Fourteen mongrel dogs, 25 to 35 kg, underwent a midline laparotomy under general anesthesia. An uncut staple line was placed 25 cm from the ligament of Treitz. In seven animals an uncut staple line alone was placed, and in the other seven animals the bowel was stapled between a sandwich of Teflon reinforcing strips such that the staples were held on both sides of the bowel by the Teflon. A jejunojejunostomy was placed 6 cm proximal to the staple line. Insulated bipolar electrical leads were placed around the staple line. After the electrical leads were monitored 2 days to 3 months postoperatively for bowel myoelectric activity, The animals were killed and the operative sites inspected. No animal suffered morbidity or mortality from the procedure. All seven unreinforced staple lines recanalized and all seven reinforced staple lines remained competent. The duodenal pacemaker potentials were transmitted through the staple line in five animals (3 controls and 2 with Teflon reinforcement) with in 1 week postoperatively. The uncut staple line does not reliably transmit the duodenal pacemaker potentials. The staple line does not recanalize when it is reinforced with a permanent material, increasing the utility of the "uncut" Roux limb operation.

Action Potentials↗
PubMed1997

Percutaneous recanalization of occlusion of central and proximal veins in chronic hemodialysis. Technical note.

Occlusion of the central and proximal veins in chronic hemodialysis patients results in considerable edema of the arm of the vascular access that is unable to drain normally. This is a formidable problem because it is very often necessary to close the vascular access, which is sometimes the last available one. To avoid resorting to this disastrous solution, recanalization of the occluded vein by percutaneous recanalization followed by endoluminal angioplasty was successfully performed in five patients (4 innominate veins and one axillary vein). Immediate failure occurred in a sixth patient, and delayed failure after two months of patency (innominate vein) in another patient for whom there had been no systematic stent placement. Recanalization was still patent in four other patients at 3, 6, 12 and 26 months. These results are an encouragement to attempt percutaneous recanalization by angioplasty of occluded central veins because, when successful, this technique makes it possible to preserve the vascular access and to avoid onerous surgery. We believe that this technique should therefore become better known.

Adult↗
PubMed1998

Improvement in left ventricular ejection fraction and wall motion after successful recanalization of chronic coronary occlusions.

AIMS: This study assessed changes in left ventricular ejection fraction and regional radial shortening after successful angioplasty of chronic coronary occlusions. METHODS: We studied 95 patients with angina pectoris or exercise-induced ischaemia with a successfully recanalized chronic (median duration 4.3 months) coronary occlusion. Intracoronary stents were implanted in 71%. Left ventriculograms were obtained at baseline and after 6.7 +/- 1.4 months. Left ventricular ejection fraction and regional radial shortening were determined by a computer-assisted method. RESULTS: Left ventricular ejection fraction increased from 0.62 +/- 0.13 at baseline to 0.67 +/- 0.11 at follow-up (P < 0.001). The change in left ventricular ejection fraction in patients with a patent artery and in patients with reocclusion (n = 8) was 0.05 +/- 0.06 and 0.01 +/- 0.04, respectively (P = 0.04). Regional radial shortening in the territory of the recanalized artery increased by 16% (from 0.28 +/- 0.11 to 0.32 +/- 0.11, P < 0.001) in patients with a patent artery at follow-up, but was unchanged in patients with reocclusion. CONCLUSION: Long-term patency after recanalization of old, chronic coronary occlusions in patients with angina pectoris is associated with improvement in global and regional left ventricular function. This may be a result of recovery of hibernating myocardium and supports the strategy of recanalizing chronic coronary occlusions.

Adult↗
PubMed2000

Recent portal or mesenteric venous thrombosis: increased recognition and frequent recanalization on anticoagulant therapy.

Characteristics and outcomes of recent portal or mesenteric venous thrombosis are ill-known. We intended to compare these features with those of patients with portal cavernoma, and also to assess the incidence of recanalization of recent thrombosis on anticoagulation therapy. All patients seen between 1983 and 1999 were enrolled into this retrospective study if recent portal or mesenteric venous thrombosis or portal cavernoma had been documented, and if cancer of the liver, pancreas, or bile duct, intrahepatic block including cirrhosis, and obstruction of the hepatic veins had been ruled out. The proportion of recent thrombosis was 7% in patients seen before 1990 and 56% after 1994 (P <.05). Patients with recent thrombosis (n = 33) or cavernoma (n = 108) did not differ with regard to age, sex ratio, or prevalence of prothrombotic states and of previous thrombotic events. In patients with recent thrombosis, septic pylephlebitis was more common and the incidence of gastrointestinal bleeding was lower (2.4 vs. 12.7/100 patient-years). Recanalization occurred in 25 of 27 patients given anticoagulation and 0 of 2 patients not given anticoagulation. The probability of recanalization was related to the extent of thrombosis (P =.003). In conclusion, mesenteric or portal venous thrombosis is increasingly recognized at an early stage. The features differentiating recent thrombosis and cavernoma are related to silent onset precluding early recognition and therapy in the latter. Frequent association with prothrombotic states and frequent recanalization on anticoagulation support the recommendation of early anticoagulation therapy in all patients with recent portal vein thrombosis.

Adult↗
PubMed2002

[Long-term results after recanalization of acute and subacute thrombotic occlusions of the infra-aortic arteries and bypass-grafts using a rotational thrombectomy device].

BACKGROUND: Evaluation of the acute and long-term results after recanalization of thrombotic occlusions of infra-aortic native arteries, stented arteries and bypass-grafts using a rotational thrombectomy device (8F Straub-Rotarex TM). MATERIALS AND METHODS: From July 2000 to February 2002, in 98 patients (64 % male, mean age 66 +/- 9 (range 47 to 90) years, mean duration of occlusion 31 +/- 33 (range 0 to 140) days, mean occlusion length 21 +/- 11 [range 2 to 40] cm) 100 vessel recanalizations were performed. 42 % of the interventions were performed during the first 14 days after the onset of the symptoms (acute occlusions). These patients were classified according to the after the TASC protocol modified SVS/ISCVS-classification: Class I: n = 22 (52 %); class lla: n = 13 (32 %); class llb: n = 6 (14 %); class III: n = 1 (2 %). Subacute and chronic occlusions were classified according to Rutherford (58 %): Stage 1: n = 5 (9 %); stage 2 and 3: n = 39 (68 %); stage 4: n = 6 (10 %); stage 5: n = 8 (13 %). RESULTS: Primary success rate was 96 % (ipsilateral interventions 99 %, cross-over 40 %). The restenosis rate after a mean follow-up of 13 +/- 4 months was 33 % for native arteries (group 1), 74 % for instent-recanalizations (group 2) and 86 % for bypass-graft occlusions (group 3). 3 % severe complications occurred: two amputations below the knee after unsuccessful recanalizations of a native artery and a bypass-graft, respectively. One death because of multiorgan failure in patient who was already in cardiac shock before the successful intervention. Further 16 complications could be solved periinterventionally. The ancle-brachial index was significantly improved during follow-up (from 0.37 +/- 0.19 to 0.82 +/- 0.22 before discharge, 0.70 +/- 0.21 after 12 months, p < 0.001). CONCLUSION: The Straub-Rotarex TM device is useful in the treatment of acute and subacute thrombotic occlusions of infra-aortic arterial and bypass-graft occlusions, with promising long-term results in native vessels but unchanged high restenosis of stented arteries and bypass-grafts.

Acute Disease↗
PubMed2006

[Guidance of interventions in subintimal recanalization and fenestration of dissection membranes using a novel dual-lumen intravascular ultrasound catheter].

PURPOSE: To evaluate the feasibility and effectiveness of IVUS-guided puncture for gaining controlled target lumen reentry in subintimal recanalization of chronic iliac/femoral artery occlusions and in fenestration of aortic dissections. MATERIALS AND METHODS: Between 5/2004 and 12/2005 12 consecutive patients (7 male, 5 female; mean age 64.6 +/- 12.0 years) with chronic critical limb ischemia and ischemic complications of aortic dissection were treated using the Pioneer catheter. This 6.2-F dual-lumen catheter combines a 20-MHz IVUS transducer with a pre-shaped extendable, hollow 24-gauge nitinol needle. This coaxial needle allows real-time IVUS-guided puncture of the target lumen and after successful reentry a 0.014" guidewire may be advanced through the needle into the target lumen. 7 patients were treated for aortic dissection and 5 patients (with failed previous attempts at subintimal recanalization) for chronic arterial occlusion. Patients with aortic dissection (5 type A dissections, 2 type B dissections) had developed renal ischemia (n = 2), renal and mesenteric ischemia (n = 2), or low extremity ischemia (n = 3). Patients with chronic arterial occlusions (2 common iliac artery occlusions, 3 superficial femoral artery occlusions) experienced ischemic rest pain (n = 4), and a non-healing foot ulcer (n = 1). RESULTS: The technical success rate using the Pioneer catheter was 100%. The recanalization/fenestration time was 37 +/- 12 min. Procedure-related complications did not occur. In 10 cases a significant improvement of clinical symptoms was evident. One patient with aortic dissection and ischemic paraplegia required subsequent surgical intervention. One patient had persistent ischemic rest pain despite successful recanalization of a superficial femoral artery occlusion. CONCLUSION: The Pioneer catheter is a reliable device which may be helpful for achieving target lumen reentry in subintimal recanalization of chronic occlusions and in fenestration of aortic dissections.

Aged↗
PubMed1991

[Percutaneous recanalization of pelvic artery occlusions--fibrinolysis, PTA, stents].

In 42 patients with symptomatic chronic iliac artery occlusions with a length of 2-15 cm (mean 4.3 cm), percutaneous recanalization was attempted. The study population was divided into 2 groups: Group I (n = 17) is a retrospective control group, the patients were treated with fibrinolysis (FL) and percutaneous transluminal angioplasty (PTA). In group II (n = 25) the patients were treated according to a prospective protocol including FL, PTA and placement of endovascular self-expandable stents. The recanalization rate for Group I and II together was 83% (35/42). FL was effective in 47%, in 53% the recanalization was performed mechanically only. The patency rate in Group I during a maximum of 69 months was 67%, in Group II, in which residual stenoses were treated with stents, 100% during max. 18 months. Obviously stents help to improve the results after percutaneous recanalization of iliac artery occlusions significantly.

Adult↗
PubMed1994

Effects of streptokinase on infarct size in rabbits in the presence and absence of coronary artery recanalization.

Despite variable efficacy in achieving recanalization, different thrombolytic agents demonstrate similar abilities to reduce mortality following myocardial infarction. We investigated whether factors other than the ability to achieve coronary artery recanalization are important in mediating the beneficial effects associated with thrombolytic therapy during acute myocardial infarction using anaesthetized rabbits. Coronary artery occlusion was produced using either a single ligature (which was released to initiate reperfusion) or by placing two ligatures 5 mm apart to allow the formation of an intraluminal thrombus. In this case, ligature removal followed by thrombolysis was required for recanalization to occur. Experiments were performed in the presence and absence of streptokinase. Streptokinase was most effective in reducing myocardial necrosis when associated with thrombolytic recanalization (total left ventricular infarct size was reduced from 37 +/- 7% to 13 +/- 1%, P < 0.01). However, streptokinase also reduced infarct size in the absence of reperfusion (45 +/- 4% vs 35 +/- 2%, P < 0.05), although further work is needed to clarify the mechanisms.

Animals↗
PubMed1995

Use of changes in ST segment elevation for prediction of infarct artery recanalization in acute myocardial infarction.

BACKGROUND: The role of the ECG in evaluating reperfusion status after thrombolytic treatment in acute myocardial infarction is not clear. Dramatic ST segment changes have been observed during recanalization of an infarct-related artery, but ST criteria have not been definitively established for prediction of coronary artery patency. Differences in ST segment changes in relation to infarct localization have not been evaluated, and further investigation is required into reciprocal ST depression, which provides information independent from ST elevation. Therefore, the aim of this study was to evaluate how early changes in ST segment elevations and depressions predict vessel patency after fibrinolysis for patients with anterior and inferior/lateral infarcts. METHODS AND RESULTS: Two hundred patients with a Pardee wave in the ECG and chest pain of less than 6 h duration were given thrombolytic treatment. The result of the therapy was assessed simultaneously with coronary angiography. Patients were divided into two groups: I (50 patients) without recanalization (TIMI grade 0, 1 or 2), and II (150 patients) with successful recanalization (TIMI grade 3). Before and after therapy, analysis of the 12 lead ECG included maximum ST elevation measurement (H1, H2 respectively), the sum of ST elevations (sigma H1, sigma H2), the sum of ST segment depressions (sigma h1, sigma h2), and the ratios of ST segment changes (R1 = H2:H1, R2 = sigma H2:sigma H1, R3 = sigma h2:sigma h1). The mean interval from the first to the second ECG was 3.5 +/- 1 h. Successive values of R1 and R2 were examined to find that which best distinguished between the two groups. The best values for prediction of reperfusion were: (1) For anterior wall infarct [table: see text] (2) For inferior and lateral infarct [table: see text] In 13 patients with a complete right or left bundle branch block in the first or second ECG, the result of treatment was predicted in 11 patients using criteria for factor R1 and in 12 patients using criteria for R2. Analysis of ST segment depressions revealed a significant correlation between normalization of ST segment depressions and elevations (R3 vs R1: r = 0.60, P < 0.05; R3 vs R2 r = 0.59, P < 0.05). Multivariate discriminant analysis showed an independent value of R3 for discrimination between the two groups, but only in patients with inferior/lateral infarcts. The overall accuracy of the common algorithm in predicting reperfusion was significantly better in patients with inferior/lateral infarcts (Chi2 test, P = 0.0078). When separate algorithms were used, there was no significant difference between patients with anterior or inferior/lateral infarcts because of the significant improvement in prediction of reperfusion in patients with anterior infarcts (McNemar's test: P = 0.041). CONCLUSIONS: We conclude that analysis of ST segments on the standard 12-lead ECG offers valuable help in the early identification of successful recanalization of infarct-related arteries after thrombolytic therapy in patients with acute myocardial infarction. Use of the ratio of ST segment normalization according to the separate criteria for anterior and inferior/lateral infarcts gives the test a high sensitivity and specificity, even in the presence of interventricular conduction disturbances.

Adult↗