Complications with thrombolysis

The incidence of hemorrhagic complications is particularly high when high doses of streptokinase are used in the treatment of deep venous thrombosis (31). High-dose streptokinase thrombolysis for 2-3 days with an initial dose of 500 000 units followed by a maintenance dose of 3 600 000 U/day led to a 10% rate of major spontaneous bleeding complications, with a fatal outcome in four older subjects out of the total of 98 patients. The fatahty rate of bleeding caused by streptokinase amounts to 7% in patients with peripheral arterial occlusion, but is much lower in younger patients with venous thromboembolism. 

M. Quintana, P. Hjemdahl, A. Sollevi, T. Kalian, M. Edner, N. Rehnqvist, E. Swahn, A.C. Kjerr, and P. Nasman, Left ventricular function and cardiovascular events following adjuvant therapy with adenosine in acute myocardial infarction treated with thrombolysis, results of the ATTenuation by Adenosine of Cardiac Complications (ATTACC) study, EurJ Clin Pharmacol 59, 1-9 (2003). 

Experience with thrombolysis in children is limited but the need for this procedure has increased because of the need to treat complications of cardiac catheterization and systemic arterial intervention. Agents used include urokinase and rtPA. Effective dose schedules for children have been extrapolated from adult studies. Coagulation and fibrinolysis are probably different in pediatrics, particularly in neonates. Plasminogen levels are known to be low in neonates, and it has been proposed that plasminogen or fresh plasma be given to enhance fibrinolytic therapy. Most centers favor iTPA, and this may be locally delivered via a selective catheter. Local low-dose therapy is unlikely to produce systemic... 

Kumar B, Agrawal N, Patra S, Marq unath CN. Occurrence of GuiUain-Barre syndrome as an inunune mediated complication after thrombolysis with streptokinase for acute anterior wall myocardial infarction a caution to be vigilant. BMJ Case Rep October 7,2013 2013. http // dx.doi.org/10.1136/bcr-2013-200602. pii bcr2013200602. 

Local intra-arterial thrombolysis (lAT) has several theoretical advantages over IV thrombolysis. For instance, by using coaxial microcatheter techniques, the occluded intracranial vessel is directly accessible and the fibrinolytic agent can be infused directly into the thrombus. This permits a smaller dose of fibrinolytic agent to reach a higher local concentration than that reached by systemic infusion, and ideally it allows for more complete recanalization with lower total doses of thrombolytic. With the smaller dose, complications from systemic fibrinolytic effects, including ICH, can theoretically be reduced. 

Ouriel K, Gray B, Clair DG, Olin J. Complications associated with the use of urokinase and recombinant tissue plasminogen activator for catheter-directed peripheral arterial and venous thrombolysis. J Vase Interv Radiol. 2000 11 295-298. 

Controversy exists regarding the actual thrombolytic effect of UK when administered in vivo. Experimental studies suggest exogenous fibrinolysis as the main pathway of thrombolysis (21). However, laboratory findings in treated patients have indicated less fibrinolytic response suggesting activity within thrombus also, In clinical practice, UK has produced similar results to streptokinase with less bleeding complications,... 

In addition to thrombolysis and aspirin, a third treatment has been shown to reduce mortality in MI, namely P-blockade. In the ISIS-1 study, atenolol 50 mg was given i.v. followed by the same dose orally. The reduction in mortality is due mainly to prevention of cardiac rupture, which appears interestingly to remain the only complication of MI that is not reduced by thrombolysis. The usual contraindications to P-blockade apply, but most patients with a first MI should be able to receive this treatment. 

Stroke may complicate myocardial infarction and is considered usually to be embolic, for its incidence correlates with the extent of myocardial infarction. Evidence indicates that the combination of thrombolysis plus aspirin lowers the overall risk of stroke, possibly by limiting the size of the infarct. 

Medical evaluation of the patient presenting with acute stroke is important because patients with cerebrovascular disease frequently have other forms of cardiovascular or other systemic disease, which may complicate medical management. If the patient is undergoing thrombolysis, bleeding from sites of systemic illness may become clinically evident. For this reason, medical teams should perform a stepwise analysis of the patient s organ systems, giving special consideration to the conditions listed in Table 10.3. 

Interest in thrombolytic therapy for acute ischemic stroke re-emerged with reports of successful thrombolysis for arterial thrombosis in the peripheral vascular system. Local lA infusion was found to have higher rates of recanalization compared with systemic IV delivery of thrombolytics without increased levels of hemorrhagic complications IV use of UK and SK was found to provide clinical benefit in patients with pulmonary embolism [5, 6]. In the early 1980s, lA infusion of UK or SK for acute MI was shown to be highly effective [5, 6]. At the same time, technical advances in endovascnlar microcatheter and microguidewire design made access to the intracranial vessels safer... 

ThomaUa, G., et al.. Outcome and symptomatic bleeding complications of intravenous thrombolysis within 6 hours in MRI-selected stroke patients comparison of a German multicenter study with the pooled data of ATLANTIS, ECASS, andNINDS tPA trials. Stroke, 2006. 37(3) p. 852-8. 

Thus, overall in the three trials that assessed the potential benefit of a strategy in which thrombolysis was combined with PCI in the treatment of acute STEMI, no evidence of clinical benefit attributable to prompt PCI following thrombolysis was apparent. By contrast, complications occurred at an increased frequency. None of the trials had been powered to assess an impact on mortality. However, the lack of improvement in left ventricular ejection fraction, enzymatic estimate of infarct size, or the incidence of reinfarction was deemed to be discouraging. Moreover, the lack of apparent benefit was associated with an increased risk of bleeding. 

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