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PubMed1991

Reperfusion injury in dog hearts with permanent occlusion of a coronary artery, probably due to reperfusion via collateral vessels.

To clarify whether or not reperfusion injury occurs in the permanent occlusion of a coronary artery, we analyzed quantitatively contraction band necrosis as an indicator of early recanalization, coagulation necrosis, infarct size and measured regional blood flow in dog hearts with collateral circulation. Fifty mongrel dogs were divided into four groups: 15 dogs with a 24-hour occlusion of the left anterior descending coronary artery just distal to the first diagonal branch (permanent occlusion group): 15 dogs a with 3-hour occlusion followed by 24-hour recanalization (recanalization group); 10 dogs with a 2-hour occlusion without recanalization (transient occlusion group); 10 dogs with a 4-hour occlusion without recanalization (transient occlusion group). The regional blood flow in the subepicardium and subendocardium determined by the generated hydrogen gas clearance method was greatly decreased 30 minutes after occlusion (14 + 8%/12 +/- 9%) and was relatively restored from 180 minutes (31 +/- 21%/21 +/- 14%) to 24 hours later (41 + 19%/26 + 16%) in spite of complete occlusion of the coronary artery. The percentage infarct area in the risk area was significantly greater in the permanent occlusion group (60 +/- 26%) than in the recanalization group (35 +/- 31%). Although most of the infarct was occupied by contraction band necrosis in the recanalization group (86 +/- 12%), contraction band necrosis was diffusely seen even in the permanent occlusion group (54 +/- 27%). In both the permanent and recanalization groups, contraction band necrosis was the main histological feature of small infarcts occupying less than 30% of the risk area, while coagulation necrosis was the main feature in very large infarcts occupying more than 80% of the risk area. In the occlusion groups without recanalization, the percentage area of contraction band necrosis in the risk area was 6 +/- 8% after the 2-hour occlusion, 23 +/- 17% after the 4-hour occlusion and 31 +/- 21% after permanent occlusion; the difference between the 4-hour and permanent occlusion groups was not significant. In the permanent occlusion group, the percentage infarct area in the risk area was inversely correlated with regional blood flow during occlusion, an indicator of collateral flow. It was concluded that reperfusion injury occurs even in hearts without recanalization. The pathogenesis may involve reperfusion in the risk area via collateral circulation. Protection against reperfusion injury is important to minimize the infarct size even in hearts with permanent occlusion, although the presence of collateral flow is an important factor in limiting infarct size.

Animals↗
PubMed2002

Clinical and vascular outcome in internal carotid artery versus middle cerebral artery occlusions after intravenous tissue plasminogen activator.

BACKGROUND AND PURPOSE: Early reperfusion is a predictor of good outcome in acute ischemic stroke. We investigated whether middle cerebral artery (MCA) occlusions have a better clinical outcome and proportion of recanalization compared with internal carotid artery (ICA) occlusion after standard treatment with intravenous (IV) tissue plasminogen activator (tPA). PATIENTS: In a retrospective analysis of our prospective stroke database between January 7, 1998, and January 30, 2002, we identified 36 consecutive patients who were treated with IV tPA within 3 hours after symptom onset of a stroke in the distribution of a documented ICA or MCA occlusion. The National Institutes of Health Stroke Scale (NIHSS) score was recorded before tPA, at 24 hours, 3 days, and 3 months after stroke. Three-month outcome was recorded by modified Rankin scale. Magnetic resonance angiography or computed tomographic angiography was obtained before tPA. The presence of recanalization was assessed by transcranial Doppler and/or magnetic resonance angiography within 3 days after stroke onset. RESULTS: Nineteen patients had MCA occlusion, and 17 had ICA-plus-MCA occlusion before tPA. Although there was no difference in age and NIHSS at day 0 between the 2 groups, the MCA group had a lower day 3 NIHSS score compared with the ICA group (P=0.006) in an ANCOVA. In addition, patients who had a MCA occlusion had lower day 1 and 3 NIHSS scores compared with the ICA group (P=0.04 and P=0.03, respectively; Wilcoxon rank sum). Similarly, NIHSS was significantly lower in patients who recanalized on days 1 and 3 (P=0.004 and P=0.003 respectively, Wilcoxon rank sum). When we adjusted for NIHSS score at day 0 in an ANCOVA, the adjusted mean was lower in the group that recanalized compared with the group that did not recanalize (P<0.001). There was a significant difference between the proportion of recanalization in the MCA group (15 of 17 recanalized, 88%) at 3 days after tPA compared with that of the ICA group (5 of 16 recanalized, 31%; P=0.001, Fisher exact test). The 3-month modified Rankin scale was not different between the 2 groups. CONCLUSIONS: Despite comparable age and NIHSS scores before IV tPA, MCA occlusions have lower day 1 and 3 NIHSS scores and higher proportion of recanalization compared with ICA occlusions. A combined IV/intra-arterial or mechanical thrombolysis may be needed to achieve early recanalization in ICA occlusions.

Adult↗
PubMedDate not supplied

Outcome of acute vertebrobasilar occlusions treated with intra-arterial fibrinolysis in 180 patients.

BACKGROUND AND PURPOSE: To evaluate predictors of recanalization and a favorable neurologic outcome in patients with acute vertebrobasilar occlusion (VBO) treated with local intra-arterial fibrinolysis (LIF). METHODS: The multicentric data of 180 patients with acute VBO treated with LIF were retrospectively evaluated. The modified Rankin scale (mRS) was used to evaluate the neurologic status before LIF and at the time of discharge. Patient's sex, age, etiology of VBO, recanalization, symptom duration before LIF, and pretreatment mRS were correlated with posttreatment mRS. Multiple logistic regression analysis was used to identify independent variables for recanalization and neurologic outcome. RESULTS: The overall mortality was 43%. Complete recanalization was achieved in 99 (55%) patients and a partial recanalization in 35 (19%) patients, respectively. Recanalization was significantly associated with a favorable outcome (P < .001). The success of recanalization was negatively correlated with the volume of the thrombus (P < .001). No correlation was found between site and etiology of VBO and recanalization. Neurologic outcome correlated strongly with the pretreatment mRS (P < .001) and also with age (P < .02). Coma lasting less than 4.5 hours led to a positive trend toward a better outcome after univariate testing (P < .001). CONCLUSIONS: Success of recanalization and neurologic status before treatment predict neurologic outcome in patients with VBO. Thrombus volume has an adverse effect on the recanalization success.

Acute Disease↗
PubMed2001

The patterns and distribution of residual abnormalities between the individual proximal venous segments after an acute deep vein thrombosis.

INTRODUCTION: The subsequent course of residual abnormalities after an acute deep vein thrombosis (DVT) can vary within individual venous segments. To investigate the pattern of response within the individual venous segment, we used sequential duplex scanning to determine whether certain segments are more likely to recanalize or remain occluded. METHODS: The anatomic segments involved in 63 above-knee DVTs were examined with duplex scanning at 1 week, 1 month, 6 months, and 1 year after the acute event. The segments under investigation were the external iliac vein (EIV), common femoral vein (CFV), superficial femoral vein (SFV), and popliteal vein (PV). Reflux studies were performed at each follow-up examination. During the follow-up period the segments were examined to see whether they were occluded, partially recanalized, or totally recanalized and the development of reflux was noted. RESULTS: Most DVTs were multisegmental with a total number of 171 sites involved. Initially, a greater number of segments were occluded (71%) than partially thrombosed (29%). The occluded segments were predominantly in the SFV and PV. At 1 year the thrombi had fully resolved in 60% of the venous segments, 27% remained partially recanalized, and 13% were occluded. The venous segments that resolved within the first 6 months had a higher rate of valvular competence than those that resolved from 6 months to 1 year. The SFV and PV had a higher incidence of valvular incompetence than the EIV and CFV. All venous segments that were partially recanalized at 1 year were found to have significant reflux. The SFV had the highest incidence of total occlusion at the end of 1 year (36%). Many of the occluded SFVs had established collateral pathways that displayed no evidence of reflux. CONCLUSION: The lower extremity venous segments differ in respect to their tendencies to partially or fully recanalize or remain occluded. All partially recanalized segments displayed reflux. Fully resolved segments that recanalized within the first 6 months were more likely to have competent valves than those that recanalized after 6 months. In the presence of an occluded SFV, collateral pathways establish rapidly. No reflux was found in these collaterals.

Acute Disease↗
PubMed1989

[Correlations between results of selective intracoronary thrombolysis and histologic findings of the infarct-related coronary arteries].

To define the histopathogenesis of successful and unsuccessful recanalization following selective intracoronary thrombolysis, coronary angiography (CAG) in thrombolysis and histologic findings were compared in 13 patients who died within four days (mean 1.5 days) after the procedure. Thirteen infarct-related arteries were evaluated in respect to recanalization; presence of an intraluminal thrombus, and rupture and hemorrhage of atheromatous plaques were histologically evaluated in serial sections. Intraluminal thrombi of the infarct-related coronary artery were found in all of the five cases with unsuccessful recanalization and in none of the eight cases with successful recanalization. Rupture and hemorrhage of atheromatous plaques in infarct-related arteries were observed in all of the five cases with unsuccessful recanalization and in seven of the eight cases with successful recanalization. It was concluded that 1) in recanalized cases, thrombi are considered to be lysed; 2) unsuccessful recanalization does not necessarily indicate the absence of thrombi; and 3) rupture and hemorrhage of atheromatous plaques do not affect recanalization.

Aged↗
PubMed1998

Local intraarterial fibrinolysis of thromboemboli occurring during endovascular treatment of intracerebral aneurysm: a comparison of anatomic results and clinical outcome.

PURPOSE: We describe our therapeutic strategy and correlate the anatomic results and clinical outcomes in patients who received immediate fibrinolytic therapy for thromboembolic complications occurring during endovascular treatment of an intracerebral aneurysm. METHODS: The medical records and angiographic examinations of 19 patients were reviewed. All endovascular procedures were performed with the patients under general anesthesia and fully heparinized. Thirteen patients received an intravenous bolus injection of aspirin. Thromboemboli occurred during catheterization or insertion of embolic material (Guglielmi detachable coils or mechanical detachable spirals) or in the first hours after the intervention. Clot distribution was within the MCA territory in 14 patients, the ACA in three patients, and the basilar trunk in two patients. A continuous intraarterial injection of urokinase was administered immediately, either superselectively distal to the thrombus or selectively within or closely proximal to the thrombus. In nine cases, chemical lysis was combined with mechanical clot fragmentation. Initial anatomic recanalization as well as clinical outcome at 3 months were evaluated. RESULTS: Ten patients showed complete recanalization and nine patients showed partial recanalization. Fourteen patients had a good clinical recovery. One patient was moderately disabled and two were severely disabled according to their scores on the Glasgow outcome scale. Two patients died, one as a consequence of the preexisting subarachnoid hemorrhage and the other because of a large intracerebral hematoma that developed after fibrinolysis. Of the 14 patients with a good clinical outcome, nine exhibited complete recanalization and five partial recanalization. CONCLUSION: Pharmacological thrombolysis seems to be a safe and efficient therapy that facilitates the natural fibrinolytic process, increasing the rate of recanalization in thromboembolic events. Clot fragmentation and superselective drug infusion appear to improve the rate of recanalization. Complete recanalization increases the chance of a better clinical outcome; however, clinical outcome does not always correspond to recanalization and vice versa.

Adult↗
PubMed1986

Importance of continued activation of thrombin reflected by fibrinopeptide A to the efficacy of thrombolysis.

Factors responsible for initial success or failure of coronary thrombolysis and persistent recanalization or early reocclusion have not been thoroughly elucidated. Both adequate initial clot lysis and preclusion of rethrombosis are required. Failure may reflect clot lysis followed immediately or somewhat later by rethrombosis. To determine whether differences in the intensity and persistence of the activation of thrombin are determinants of success or failure of recanalization, plasma fibrinopeptide A, a fibrinogen product liberated by thrombin, was serially assayed in 19 patients treated with intravenous streptokinase. In patients exhibiting recanalization (n = 9), plasma fibrinopeptide A decreased after administration of streptokinase but before administration of heparin. In patients without initially apparent recanalization, fibrinopeptide A increased, suggesting ongoing thrombosis, and subsequently decreased promptly after heparin. In patients with initial recanalization followed by overt reocclusion the pattern was different. Despite recanalization, fibrinopeptide A continued to rise markedly. Elevations persisted despite administration of heparin. Thus, inhibition of activation of thrombin is associated with successful recanalization. Conversely, persistent activation of thrombin may be a predisposing factor to both apparent initial failure of recanalization and overt early reocclusion.

Coronary Disease↗
PubMed1999

Evaluation of reperfusion and recovery of brain function before and after intracarotid arterial urokinase therapy in acute cerebral infarction with brain SPECT.

PURPOSE: Perfusion defects can be demonstrated reliably at an early stage with regional cerebral blood flow studies using SPECT. The administration of thrombolytic therapy in ischemic stroke is targeted at restoring cerebral perfusion immediately, leading to salvage of ischemic penumbra, smaller infarct size, and improved clinical outcome. This study considered the role of brain perfusion SPECT in the evaluation of reperfusion and brain function recovery of the infarcted area after early recanalization (less than 6 hours) of the occluded artery using intracarotid arterial urokinase therapy (ICAU). METHODS: Intracranial artery occlusion was confirmed in seven patients using emergency carotid angiography performed within the initial 6-hour period. Intracarotid arterial urokinase (500,000 to 800,000 units) was administered into the occluded arterial system (the left middle cerebral artery in four and the right middle cerebral artery in three patients). CT scanning was performed when the patients arrived in the emergency department and was repeated 24 to 48 hours after ICAU and at 7 days or earlier if clinically indicated. All patients had two SPECT studies, the first before urokinase administration and the second 24 or 48 hours later. RESULTS: Complete recanalization of the occluded vessels was seen in one patient after ICAU, effective partial recanalization was achieved in four patients, and minimal recanalization occurred in the other two. Before ICAU, Tc-99m HMPAO brain SPECT showed decreased uptake of the infarcted area in all patients, whereas the follow-up brain SPECT performed 24 or 48 hours after ICAU revealed improvement in the uptake of the recanalized area on qualitative and semiquantitative assessments using an asymmetry index, suggestive of brain function recovery and clinical improvement. Hemorrhagic transformation adjacent to the reperfused regions occurred in two patients with partial recanalization of the left middle cerebral artery. CONCLUSIONS: Reperfusion of the recanalized area and brain function recovery could be achieved if the occluded artery is recanalized within the initial 6-hour period using ICAU, and this was documented using brain perfusion SPECT without a delay in the therapeutic time window. Because the number of patients we studied was limited, further study is necessary to evaluate the effect of ICAU and to determine its prognostic significance.

Acute Disease↗
PubMed1989

Serial angiographic assessment of coronary artery obstruction and collateral flow in acute myocardial infarction. Report from the second Mount Sinai-New York University Reperfusion Trial.

In the Second Mt. Sinai-New York University Reperfusion Trial, in which change of ejection fraction was the primary end point, the following secondary end points were prospectively assessed by serial coronary angiography: patency of the infarct artery both before intervention and 10-14 days later, acute and delayed recanalization rates, presence or absence of collateral flow, and complication rates of acute interventional catheterization. We assigned 393 patients randomly to groups receiving acute cardiac catheterization and a double-blind intracoronary infusion of streptokinase (SK arm), both streptokinase and nitroglycerin (SK-NTG arm), nitroglycerin alone (NTG arm), or conventional therapy without acute catheterization (control arm). Prospective stratification was based on duration of infarct pain before randomization: group A, less than 2 hours; Group B, 2-12 hours. Baseline patency rates were comparable in patients studied within 6 hours (30%, 40 of 135) and those studied later (24%, 32 of 133). This finding refutes the hypothesis that spontaneous recanalization occurs frequently after 6 hours. The acute recanalization rates of the SK arm (60%, 40 of 67) and the SK-NTG arm (63%, 29 of 62) did not differ. During streptokinase infusion, more vessels recanalized in group A (81%, 22 of 27) than in group B (56%, 57 of 102) (p less than 0.01); this was due to a significant reduction of recanalization rates from 75% (48 of 64) to 45% (26 of 62) with treatment after 6 hours (p less than 0.01). Delayed recanalization, that is, patency at end point but not postintervention, was seen in 17% (17 of 100) of total occlusions treated with streptokinase. In group A, all total occlusions treated with streptokinase recanalized either acutely (20 of 22) or delayed (two of 22), whereas in group B, 23% (18 of 78) remained obstructed. The reocclusion rate in the SK arms was 17% (11 of 65). In the NTG arm, recanalization occurred during intervention in 4% (two of 47) and delayed in 45% (21 of 47). At end-point angiography, the patency rates of the NTG arm (62%, 41 of 66) and the control arm (58%, 36 of 62) were comparable; those of the SK arms were higher (75%, 105 of 140) (p less than 0.01). Total occlusion was associated with collateral flow in 33% (66 of 199) at baseline; the prevalence of collaterals did not increase with time to angiography, which indicates that they had developed before the index event.(ABSTRACT TRUNCATED AT 400 WORDS)

Angiography↗
PubMed1987

Acute electrocardiographic changes associated with successful coronary thrombolysis in acute myocardial infarction.

In this study ECG changes were analyzed to assess the acute effects of antegrade blood flow on the ECG in patients with AMI. The study population consisted of 22 patients with MI in whom the totally occluded left anterior descending artery (LAD) or right coronary artery (RCA) was recanalized by intracoronary urokinase infusion (recanalized group) and 14 patients in whom the occluded coronary artery was not successfully recanalized (control group). No significant difference was found in the sum of ST segment elevation (V2-V4 leads for the LAD-occluded group, II, III and aVF leads for the RCA-occluded group) before urokinase infusion. In the recanalized group sigma ST abruptly increased in 5 min after recanalization in 13 of 16 LAD-occluded patients from 1.49 +/- 0.89 mV to 2.44 +/- 1.67 mV (p less than 0.005), and in 4 of 6 RCA-occluded patients from 0.66 +/- 0.12 mV to 1.42 +/- 0.52 mV (p less than 0.01). However increased sigma ST in the recanalized group was reduced to the control value existing before recanalization within 30 min after recanalization and continued to decline more rapidly than in the control group. These transient ST segment elevations were not correlated with long-term angiographic determinants of left ventricular function. We conclude that ST segment shows abrupt augmentation after successful thrombolysis and that continuous ST segment monitoring is useful for assessing thrombolysis in AMI.

Adult↗
PubMed1992

[Efficacy of intracoronary thrombolysis versus percutaneous transluminal coronary angioplasty for treating acute myocardial infarction].

The usefulness of percutaneous transluminal coronary angioplasty (PTCA) in patients with evolving myocardial infarction remains controversial. We retrospectively assessed the efficacy of PTCA on myocardial salvage in acute myocardial infarction in comparison with the efficacy of intracoronary thrombolysis (ICT). Sixty-two patients with initial anteroseptal myocardial infarction who had been treated within 6 hrs after the onset of chest pain were categorized into 4 groups: 1) spontaneous recanalization: n = 14, 2) successful PTCA: n = 25 (this group was further subdivided into 2 groups: direct PTCA group, primary PTCA without prior ICT: n = 19; and rescue PTCA group, PTCA after unsuccessful ICT: n = 6), 3) successful ICT group (n = 12), and 4) unsuccessful recanalization group (n = 11). Left ventricular function in the chronic phase was assessed by contrast ventriculography using the global ejection fraction (EF) and regional wall motion (RWM) was assessed by the centerline method. Patients with recanalization had a significantly higher EF than did those without (62 +/- 12 vs 50 +/- 13%, p < 0.01). The mean EFs for groups with successful reperfusion were as follows: 65 +/- 8% for the spontaneous recanalization group, 61 +/- 14% for PTCA group (64 +/- 13% for direct PTCA group, 51 +/- 13% for rescue PTCA group) and 60 +/- 12% for the ICT group. The EFs for the spontaneous recanalization group and the direct PTCA group were significantly greater than that for the rescue PTCA group. The time to reperfusion and the thrombolysis in myocardial infarction (TIMI) flow grade before reperfusion did not affect the preservation of global left ventricular function. RWM of the infarcted area in patients with recanalization were less hypokinetic than that in patients without (p < 0.01). The mean RWM (SD/chord) in the successfully reperfused groups were -2.3 +/- 1.2 for the spontaneous recanalization group, -2.6 +/- 1.2 for the PTCA group (-2.3 +/- 1.1 for the direct PTCA group, -3.3 +/- 1.0 for rescue PTCA group) and -3.0 +/- 0.5 for the ICT group. Hypokinesis of the infarcted area was more severe in the rescue PTCA group than in the spontaneous recanalization group and the direct PTCA group (multiple comparison test p < 0.01, respectively), and hypokinesis was more severe in the ICT group than in the direct PTCA group (Student's t-test, p < 0.05).(ABSTRACT TRUNCATED AT 400 WORDS)

Adult↗
PubMed1991

[Thrombolysis in acute occlusion of cerebral blood vessels].

Thrombolysis may achieve recanalization in cases of occlusion of the cerebral vessels. If therapy is initiated in good time, development of cerebral infarction may be at least partially prevented. Thrombolytic treatment was performed in 14 patients at the Wagner-Jauregg Hospital within a period of one year. Urokinase was given locally, while rtPA was applied locally and/or systemically. 4 patients had an occlusion of the internal carotid artery, 6 an occlusion of the middle cerebral artery, and 4 an occlusion of the basilar artery. Complete recanalization was achieved in 6 patients, partial recanalization in 4, and no recanalization in 4. The neurological outcome of the cases with complete recanalization was good with the exception of one patients who died. Partial recanalization resulted in a fair outcome in 2 patients, while the other 2 died. 3 out of the 4 patients in whom no recanalization was achieved died. Our findings show that this form of therapy may considerably improve the natural history of the disease, provided recanalization is achieved in good time. They encourage us to continue this form of therapy and to work at improving the therapeutic criteria.

Aged↗
PubMed2006

Late angiographic and clinical follow-up results of 100 consecutive aneurysms treated with Onyx reconstruction: largest single-center experience.

We present the long-term clinical and angiographic follow-up results of 100 consecutive intracranial aneurysms treated with Onyx liquid embolic system (MTI, Irvine, Calif.), either alone or combined with an adjunctive stent, in a single center. A total of 100 aneurysms in 94 patients were treated with endosaccular Onyx packing. Intracranial stenting was used adjunctively in 25 aneurysms including 19 during initial treatment and 6 during retreatment. All aneurysms except two were located in the internal carotid artery. Of the 100 aneurysms, 35 were giant or large/wide-necked, and 65 were small. Follow-up angiography was performed in all 91 surviving patients (96 aneurysms) at 3 and/or 6 months. Follow-up angiography was performed at 1, 2, 3, 4 and 5 years in 90, 41, 26, 6 and 2 patients, respectively. Overall, aneurysm recanalization was observed in 12 of 96 aneurysms with follow-up angiography (12.5%). All 12 were large or giant aneurysms, resulting in a 36% recanalization rate in the large and giant aneurysm group. One aneurysm out of 25 treated with the combination of a stent and Onyx showed recanalization. There was also no recanalization in the follow-up of small internal carotid artery aneurysms treated with balloon assistance only. At final follow-up, procedure- or device-related permanent neurological morbidity was present in eight patients (8.3%). There were two procedure-related and one disease-related (subarachnoid hemorrhage) deaths (mortality 3.2%). Delayed spontaneous asymptomatic occlusion of the parent vessel occurred in two patients, detected on routine follow-up. Onyx provides durable aneurysm occlusion with parent artery reconstruction resulting in perfectly stable 1-year to 5-year follow-up angiography both in small aneurysms treated with balloon assistance only (0% recanalization rate) and large or giant aneurysms treated with stent and Onyx combination (4% recanalization rate). Endosaccular Onyx packing with balloon assistance may not be adequate for stable long-term results in those with a large or giant aneurysm. However, the recanalization rate of 36% in these aneurysms is better than the reported results with other techniques, i.e., coils with or without adjunctive bare stents.

Adolescent↗
PubMed1981

Changes in left ventricular function after intracoronary streptokinase infusion in clinically evolving myocardial infarction.

Left ventricular (LV) contrast cineventriculograms were obrained in 174 patients with evolving acute myocardial infarction (AMI) treated by intracoronary streptokinase (SK) infusion. Ejection fraction (EF) increased slightly, from 52% +/- 13% before admission SK intervention to 58% +/- 13% immediately after early recanalization of the completely obstructed coronary vessel (p less than 0.0005, n = 68), while local wall motion usually improved. Immediately improved LV function appears to be the result of early reperfusion and/or decreased LV afterload. In 55 chronic (long-term follow-up) post-AMI (2 to 4 weeks after successful early SK reperfusion) patients, repeat angiography revealed late reocclusion of the infarct vessel in nine patients. Chronic EF was not significantly different from pre-SK intervention EF in these nine patients with late reocclusion, whereas in the remaining 46 patients with persistent patency, EF increased mildly from 52% +/- 13% (before SK intervention) to 56% +/- 16% (in long-term recanalization) (p less than 0.025). Ventricular loading conditions were not different at pre-SK intervention angiography and chronic angiography. EF rose modestly from 51% +/- 14% to 57% +/- 18% in the 23 patients recanalized on follow-up, in whom pre-SK intervention angiography revealed collaterals to the infarcting area (p less than 0.025), whereas there was no EF change in the 23 chronically recanalized patients without pre-SK collaterals. In the eight patients recanalized at late follow-up, who had preadmission chest pain for less than 3 hours and successful SK reperfusion within 4 hours of symptom onset (group A), EF increased significantly from 51% +/- 12% to 65% +/- 6% (p less than 0.025). In the 25 chronically recanalized patients admitted 3 to 6 hours after onset of chest pain, in whom SK reperfusion was successful (group B), EF was unchanged at late study. In the 13 chronically recanalized patients with preadmission chest pain lasting longer than 6 hours, in whom SK reperfusion was successful (group C), EF increased from 52% +/- 13% before SK intervention to 56% +/- 16% at late study (p less than 0.025). Pre-SK intervention angiography revealed collateral vessels to the infarct area in 69% of group C patients but in only 42% of patients in groups A and B. These findings suggest that the critical interval for myocardial salvage, as well as for early and long-term improvement of LV function by SK reperfusion at admission, is 4 hours after onset of chest pain in the majority of AMI patients. This time interval may be longer in patients with well-developed collateral supply to the region of the acute infarct.

Cardiac Output↗
PubMed2005

Patterns of venous insufficiency after an acute deep vein thrombosis.

BACKGROUND: The purpose of this study was to investigate patterns of venous insufficiency during a 12-month period after an acute deep vein thrombosis. STUDY DESIGN: Seventy limbs in 67 patients with an acute deep vein thrombosis (DVT) involving 147 anatomic segments were evaluated with duplex scanning at 1 month, 3 months, 6 months, and 1 year. Venous segments were examined whether they were occluded, partially recanalized, or totally recanalized, and the development of venous reflux was evaluated. RESULTS: The segments investigated were the common femoral vein (38 segments), femoral vein (33 segments), popliteal vein (36 segments), and calf veins (40 segments). There were 35 limbs with isolated DVT and the remaining 35 had multisegment DVT. At 1 year, thrombi had fully resolved in 76% of the segments, 20% remained partially recanalized, and 5% were occluded. The venous occlusion was most predominant in the femoral vein (21%) at 1 year. On the contrary, rapid recanalization was obtained in calf veins than in proximal veins at each examination (p < 0.01). Deep vein insufficiency was detected as early as 1 month after development of DVT, and the reflux was most predominant in popliteal veins (56%), followed by femoral veins (18%). No reflux was found in calf veins. Multisegment DVTs had a significantly higher incidence of deep vein insufficiency than single segment DVTs at 1 year. Development of superficial venous insufficiency was found in 5 limbs (7%) and perforating vein insufficiency in 5 (7%). CONCLUSIONS: Lower extremity venous segments showed different proportions of occlusion, partial recanalization, and total recanalization. Calf veins showed more rapid recanalization than proximal veins. Venous reflux was noted as early as 1 month. The limbs involving multisegment DVTs on initial examination had a higher incidence of deep vein insufficiency and could require much longer followup studies.

Acute Disease↗
PubMed1987

Thrombolysis in myocardial infarction (TIMI): comparative studies of coronary reperfusion and systemic fibrinogenolysis with two forms of recombinant tissue-type plasminogen activator.

Coronary recanalization rates and changes in plasma proteins of the fibrinolytic system were evaluated with two preparations of recombinant tissue-type plasminogen activator (rt-PA): the early formulation in liquid excipient ("old" rt-PA) and the later lyophilized form ("new" rt-PA). The dose dependency of coronary recanalization and of effects on plasma proteins was evaluated for the new rt-PA. Four groups of patients were studied: Study 1, 80 mg old rt-PA infused intravenously over 3 hours (n = 113); Study A, 80 mg new rt-PA over 3 hours (n = 47); Study B, 100 mg new rt-PA over 3 hours (n = 83); and Study C, 150 mg new rt-PA over 6 hours (n = 62). With equal doses of 80 mg, coronary recanalization rates at 90 minutes of infusion, determined angiographically, averaged 62% (Study 1) and 45% (Study A) with no overlap of 95% confidence limits. Increasing the dose of the new rt-PA to 100 mg, recanalization rates at 90 minutes averaged 71% (Study B), similar to those observed in Study 1. An increase to 150 mg resulted in higher recanalization rates at 30 minutes of infusion, 42% compared with 24% in Study 1 with no overlap of 95% confidence limits, and comparable rates at 90 minutes, 76 versus 62%. A linear trend test indicated a significant relation (p less than 0.01) between the dose of the new rt-PA and the rate of coronary recanalization at 30, 60 and 90 minutes of infusion. The new rt-PA affected plasma proteins of the fibrinolytic system less than the old form. There was a dose-dependent relation (p less than 0.001) in the effect of the new rt-PA on the plasma proteins. The frequency of bleeding complications was similar in the four study groups. These results indicate that the new rt-PA is less potent than the old rt-PA, in relation to both coronary reperfusion and systemic fibrinogenolysis. A higher and longer dosage regimen caused more rapid recanalization with similar effects on fibrinogenolysis.

Aged↗
PubMed1999

Transcervical falloscopic dilatation of proximal tubal occlusion. Is there an indication?

Proximal tubal occlusion (PTO), until recently a domain of microsurgery, can also be treated by a transcervical balloon dilatation and/or tubal recanalization. The aim of our study was to evaluate the possibility of transcervical tubal dilatation during transcervical Falloposcopy. Transcervical Falloposcopy and tubal dilatation was performed under laparoscopic control. During a period of 48 months a total of 157 Falloposcopies was performed. Out of a total of 157 patients, 42 patients had PTO confirmed by dye-pertubation during laparoscopy. All patients were referred because of primary or secondary tubal infertility. A total of 18 patients had bilateral PTO by dye-pertubation and of these six patients had successful bilateral and seven patients successful unilateral recanalization. The remaining five patients were unable to recanalize. A total of 24 patients had an unilateral PTO by dye-pertubation, 13 of these patients had a contralateral diseased tube, seven of which could be recanalized. Four patients had contralateral normal tubes, with successful recanalization in one patient. Seven patients had an occluded or missing contralateral tube, five of which could be recanalized. A total of 60 tubes with PTO were diagnosed, of which 32 (53.3%) tubes could be recanalized. 20 of these had normal tubes. Only patients with healthy Fallopian tubes carried pregnancies to term (five pregnancies, 12% of all patients). All patients conceived within a period of 3-6 months. We observed no ectopic pregnancy.

Adult↗
PubMed2006

The utility of quantitative calf muscle near-infrared spectroscopy in the follow-up of acute deep vein thrombosis.

BACKGROUND: To investigate patterns of venous insufficiency and changes in calf muscle deoxygenated hemoglobin (HHb) levels after an acute deep vein thrombosis (DVT). METHODS: A total of 78 limbs with an acute DVT involving 156 anatomic segments were evaluated with duplex scanning and near-infrared spectroscopy (NIRS) at 1, 3, 6 and 12 months. Venous segments were examined whether they were occluded, partially recanalized, and totally recanalized, and the development of venous reflux was noted. The NIRS was used to measure calf muscle HHb levels. Calf venous blood filling index (HHbFI) was calculated on standing, then the calf venous ejection index (HHbEI), and the venous retention index (HHbRI) were obtained after exercise. RESULTS: The segments investigated were the common femoral vein (CFV; 38 segments), femoral vein (FV; 37), popliteal vein (POPV; 44), and calf veins (CV; 37). At 1 year, thrombi had fully resolved in 67% of the segments, 27% remained partially recanalized, 6% were occluded. The venous occlusion was predominant in the FV (24%) at 1 year. On the contrary, rapid recanalization was obtained in CV than proximal veins at each examination (P < 0.01). Venous reflux was predominant in POPV (55%), followed by FV (19%), and no reflux was found in CV. At 1 year, the HHbFI in POPV reflux patients was significantly higher than those with resolution (0.19 +/- 0.14, 0.11 +/- 0.05 microm s, P = 0.009, respectively). Similarly, there was a significant difference in the HHbRI between the two groups (3.08 +/- 1.91, 1.42 +/- 1.56, P = 0.002, respectively). In patients with FV occlusion, the value of HHbRI was significantly higher than those with complete resolution (2.59 +/- 1.50, 1.42 +/- 1.56, P = 0.011, respectively). CONCLUSIONS: The lower extremity venous segments show different proportions of occlusion, partial recanalization, and total recanalization. The CV shows more rapid recanalization than proximal veins. The NIRS-derived HHbFI and HHbRI could be promising parameters as the overall venous function in the follow-up of acute DVT. These findings might be very helpful for physician in detecting patients who require much longer follow-up studies.

Acute Disease↗