**24. Fibrinolytic treatment**

#### **24.1. Alteplase**

In recent years, alteplase has become the most widely used fibrinolytic drug in children. The most important reasons for selection are that the half-life is short (approximately 5 mins), it is not antigenic and the effect is fibrin-specific [78]. It is a recombinant tissue plasminogen activator. In literature, there is no standard application related to r-tPA dosage in Paediatric patients. There are different applications in different centres. Nakagawa et al. applied intracoronary tPA at the dose of 200,000 unit/kg (0.34 mg/kg) to a patient with Kawasaki disease who suffered MI, but the patient died [79]. Subsequently, doses of 400,000 unit/kg (0.69 mg/ kg) and 800,000 unit/kg (1.38 mg/kg) intra-coronary tPA were applied to 2 other patients with Kawasaki disease who suffered MI, and the thrombi and cliinical findings of the patients were determined to have recovered without any complications. In addition to the tPA, Nakagawa et al. also administered urokinase infusion to the first and third of these three patients. Tsubata et al. applied a dose of 300,000 unit/kg tPA to an MI patient with Kawasaki disease as 10% of the total dose in bolus form and the remainder with a 1-hour infusion [80]. After 2 days, a dose of 50,000 unit/kg tPA was administered intra -coronary, but only a partial response was obtained in the thrombus. Krendal et al. treated a 7-year old Kawasaki patient with MI with intravenous 700,000 unit/kg tPA and a response was obtained clinically on echo. The success in that case compared to Tsubata et al. was associated with the administration of high-dose tPA [81].

In cases of intracardiac thrombus and intravascular thrombose**s,** while some centres have used 0.05–0.5 mg/kg/hr. infusion after 0.3–0.6 mg/kg bolus, other centres have administered infusion of 0.01–0.5 mg/kg/hr. without any loading dose, until the thrombus is resolved (max 96 hrs). This has been used and successful results have been obtained in Paediatric cases, especially in the opening of a central venous catheter and in intracardiac or intra-arterial and intravenous thrombus cases [83–86].

After a loading dose of 0.1 mg/kg/10 mins in neonatal infants, some centres have administered maintenance at 0.3 mg/kg/hr. while others have given a loading dose of 0.7 mg/kg in 30—60 mins followed by 0.2 mg/kg/hr. As the infusion time extends, so the possibility of complications developing increases [82, 83]. Major complications that can develop are intracranial bleeding, epistaxis, melena and hematuria and minor complications may be seen as mucosal bleeding or bleeding from the needle entry site. Therefore, patients must be closely monitored. In patients who develop complications, plasminogen or fibrinogen levels in the blood are examined, and if necessary the treatment must be stopped.

**26. Anticoagulant treatment**

**27. Anti-aggregant treatment**

adult patients after MI [23].

because of the vasodilatory properties.

Meki Bilici\*, Mehmet Ture and Hasan Balik

Authors declare that they have no conflict of interest to declare.

\*Address all correspondence to: drmekibilici@hotmail.com

**27.1. Beta blockers**

**Conflict of interest**

**Author details**

Anticoagulation is recommended for all patients in addition to antiplatelet therapy during primary PCI [23]. The most commonly used drug for this is unfractioned heparin. The initial dose is given in bolus form as 70–100 units/kg and in maintenance, it can be given according to the active clotting time or as 10–15 units/kg/hr. After admission to hospital, it can be terminated within 8 hours of clearance of the coronary occlusion or it can be continued intra venously for 24–48 hrs to heparinisation. The goal is an aPTT value of 50–70 seconds or 1.5–2 fold the control value. It is recommended that the test is repeated at 3, 6, 12 and 24 hours [23].

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As aspirin is given at the classic anti-aggregant dose (75-100 mg) following classic anti-aggregant dose loading (150-300 mg) in adult MI cases, in Paediatric cases loading is given of 5 mg/kg/day followed by 3-5 mg/kg/day aspirin. Adolescents can benefit from doses similar to those of adults. The administration of clopidogrel together with aspirin increases the chance of success. The recommended Paediatric dose for clopidogrel is 0.2 mg/kg/day [89]. In adult patients diagnosed with MI, after 300 mg loading, maintenance treatment is given of 75 mg/day clopidogrel. It is recommended that clopidogrel and aspirin treatment is continued for 12 months in

When arrythmia has been determined in MI patients, electrolyte levels must be examined and if the electrolyte levels are normal, beta blockers are preferred in treatment. Metoprolol can be given for this at a single dose of 1-2 mg/kg/day [23]. In addition to the anti-arrhythmic effects of beta blockers, patients who have undergone MI also beenfit from the anti-ischaemic effect

Department of Pediatric Cardiology, Dicle University Medical Faculty, Diyarbakir, Turkey

In adult cases, following a 15 mg iv bolus dose, 0.75 mg/kg/hr. is administered in 30 mins. The success of fibrinolytic treatment is evaluated with the correction of ST elevation and the patient symptoms [23].

As Paediatric MI cases are emergencies and the condition is urgent and life-threatening, it may be more appropriate to administer intra-coronary or iv high-dose bolus treatment followed by 0.1–0.5 mg/kg /hr. infusion.

### **24.2. Reteplase**

Unlike alteplase, there is no need for an infusion following the administration of IV bolus. To open blocked catheters in Paediatric patients, 0.1 units was administered and in cases where no response could be obtained, increases were applied of 0.1 units up to a maximum of 0.4 units. Successful results have been obtained with this treatment [85]. In adult coronary thrombo-embolic cases, it is recommended that 10 units are given in the form of 2 doses at a 30-min interval [23].

### **24.3. Tenecteplase**

This is a drug given in bolus form to myocardial infarction patients after diagnosis [23]. Unlike other tissue plasminogen activators, it is a time-saving application as there is no requirement for repeated bolus doses. The recommended doses for adults are 30 mg (6000 unit) for patients <60 kg in weight, 35 mg for those weighing 60–70 kg, and 40 mg for those of 70–80 kg [23].

#### **24.4. Streptokinase**

Streptokinase has been used for many years in adult MI patients. Experience related to the efficacy of streptokinase in PMI has been acquired from Kawasaki patients in particular. Studies have shown that in Kawasaki patients with MI, the use of intravenous or intra-coronary streptokinase followed by heparinisation and warfarin or dipyridamol in maintenance, is effective [87, 88]. If Percutaneous Coronary Intervention (PCI) is not applied within the first 2 hours after diagnosis in cases with MI, immediate thrombolytic treatment should be applied with a half-hour infusion. Fibrinolytic treatment can be administered to patients diagnosed with MI within the first 12 hours of diagnosis [23].
