Ischemic cerebral infarction after rt-PA and heparin therapy for acute myocardial infarction. The TIMI-II pilot and randomized clinical trial combined experience

Ischemic stroke complicating thrombolytic therapy with tenecteplase for ST elevation myocardial infarction: two case reports

BACKGROUND

Hemorrhagic complications are quite common in the rare cases where thrombolysis is performed. Ischemic stroke in the aftermath of thrombolysis for a ST elevation myocardial infarction is a very rare and paradoxical complication. With these observations in mind we report two interesting cases of ischemic stroke which occurred after fibrinolytic therapy with tenecteplase for a ST elevation myocardial infarction.

CASE PRESENTATION

The first case was a 56-year-old African man who presented with an acute infero-basal ST elevation myocardial infarction 6 hours after chest pain onset. Thrombolysis with tenecteplase was performed and few minutes later an ischemic stroke occurred. The second patient was a 65-year-old African man who presented with an acute infero-basal ST elevation myocardial infarction 5 hours after chest pain onset. Thrombolysis was performed and 10 hours later an ischemic stroke occurred.

CONCLUSIONS

Hemorrhagic stroke is not the only complication of thrombolysis, ischemic stroke can occur even if it is an extremely rare complication. The two cases on which we report shed light on the association between fibrinolytic therapy and ischemic stroke, the pathophysiology of which is not well understood.

Neurologic complications of myocardial infarction

Cardiac disease, in particular coronary artery disease, is the leading cause of mortality in developed nations. Strokes can complicate cardiac disease - either as result of left ventricular dysfunction and associated thrombus formation or of therapy for the cardiac disease. Antiplatelet drugs and anticoagulants routinely used to treat cardiac disease increase the risk for hemorrhagic stroke.

Antithrombotic medication for cardioembolic stroke prevention

Embolism of cardiac origin accounts for about 20% of ischemic strokes. Nonvalvular atrial fibrillation is the most frequent cause of cardioembolic stroke. Approximately 1% of population is affected by atrial fibrillation, and its prevalence is growing with ageing in the modern world. Strokes due to cardioembolism are in general severe and prone to early recurrence and have a higher long-term risk of recurrence and mortality. Despite its enormous preventive potential, continuous oral anticoagulation is prescribed for less than half of patients with atrial fibrillation who have risk factors for cardioembolism and no contraindications for anticoagulation. Available evidence does not support routine immediate anticoagulation of acute cardioembolic stroke. Anticoagulation therapy's associated risk of hemorrhage and monitoring requirements have encouraged the investigation of alternative therapies for individuals with atrial fibrillation. New anticoagulants being tested for prevention of stroke are low-molecular-weight heparins (LMWH), unfractionated heparin, factor Xa inhibitors, or direct thrombin inhibitors like dabigatran etexilate and rivaroxaban. The later exhibit stable pharmacokinetics obviating the need for coagulation monitoring or dose titration, and they lack clinically significant food or drug interaction. Moreover, they offer another potential that includes fixed dosing, oral administration, and rapid onset of action. There are several concerns regarding potential harm, including an increased risk for hepatotoxicity, clinically significant bleeding, and acute coronary events. Therefore, additional trials and postmarketing surveillance will be needed.

Do we need echocardiography before commencing thrombolytic therapy?

We report a case of a 41-year-old man who had fatal multiple cerebral and bilateral renal infarcts 1 hour after initiation of thrombolytic therapy for acute ST elevation myocardial infarction. Echocardiography study disclosed dilated left ventricle with severe global hypokinesia suggestive of preexisting cardiomyopathy and a disintegrated left ventricular apical thrombus pointing out to the source of the embolic complication. This raises the question whether echocardiography before initiating thrombolytic therapy would affect the decision of commencing thrombolytic therapy and help avoiding such lethal embolic complications.

A case of paradoxical embolism "in situ" associated with massive pulmonary embolism: role of echocardiography

A 49-year-old man was admitted in transfer for further management of a pulmonary embolism (PE) and possible mitral valve vegetation. Transthoracic echocardiography performed at our institution showed evidence of right ventricular (RV) enlargement and dysfunction. Within the right atrium was a serpentine mobile thrombus which traversed the interatrial septum at the level of the fossa ovalis and extended into the left atrium to the level of the anterior mitral valve leaflet. Because of the patient's dyspnea, RV dysfunction, and large clot burden, thrombolytic therapy was considered and would have been administered had the thrombus in situ not been identified. In light of the thrombus in situ and the concern about possible systemic embolization with thrombolytic therapy, the patient underwent successful surgical thrombectomy. This case highlights the importance of echocardiography in the management of patients with PE. We believe that all patients should undergo echocardiography prior to receiving thrombolytic therapy for pulmonary emboli. Careful interrogation of the interatrial septum for the presence of a thrombus in situ is warranted. Thrombectomy should be considered in individuals with PE who have a thrombus in situ.

Restoration of hearing loss with tissue plasminogen activator. Case report

A 59-year-old man with a 2-year history of sudden onset of hearing loss in the left ear was treated with tissue plasminogen activator (tPA) for myocardial infarction. The patient had 50 dB of hearing recovery after the full dose (100 mg of tPA followed by 3 mg/d of tPA for 2 weeks).

Intravenous infusion of recombinant tissue plasminogen activator for the treatment of patients with sudden and/or chronic hearing loss

Seventeen patients with sudden hearing loss and 10 patients with chronic hearing loss were treated with intravenous infusion of tissue plasminogen activator. For sudden hearing loss, the recombinant tissue plasminogen activator was used, and 3 mg (in 3 mL of diluent) was diluted into 250 mL of physiological saline solution and given intravenously every 12 hours. Sixteen patients of the sudden hearing loss group and all 10 patients of the chronic hearing loss group showed an improvement after this treatment. No patients had side effects from the treatment. The results indicate that this would be an excellent mode of therapy for patients with hearing loss.

Embolization of calcific thrombi after tissue plasminogen activator treatment

BACKGROUND AND PURPOSE

Embolic stroke has been reported after thrombolysis in cardiac patients but has not yet been documented after thrombolytic therapy for acute ischemic stroke.

DESCRIPTION OF CASES

Patient 1 had a calcific embolus in the right M1 region on head computed tomography (CT) scan when treated with tissue plasminogen activator (tPA). Repeat imaging within hours showed distal migration of calcific fragments into the M2 region. Patient 2 had a calcific embolus in the right M1 region, as well as distal calcific emboli in multiple vascular distributions on initial head CT scan. She was treated with intravenous tPA but became unresponsive within 2 hours. Repeat imaging showed new calcium-density signal in the basilar artery.

CONCLUSIONS

We present 2 cases of radiographically evident, calcific embolization after tPA therapy for acute ischemic stroke. Emboli with a calcific component may lyse with tPA, but such patients should be carefully monitored for distal or recurrent embolization.

Ventricular septal defect and left ventricular aneurysm: late occurrence as complications of an acute myocardial infarction

Mechanical complications of acute myocardial infarction (AMI) such as a ventricular septal defect (VSD) usually occur within the first week. In the thrombolytic era, the incidence of a VSD has not increased, but has been reported to occur earlier than previously described. We report an unusual case of an elderly Caucasian female with an acute anterior wall myocardial infarction treated with thrombolytic therapy. Her AMI was complicated by pulmonary edema secondary to a VSD and a left ventricular aneurysm five weeks later. Prompt diagnosis, immediate surgical closure of the VSD, and aneurysmectomy resulted in her complete recovery.