Treatment of ischemic stroke complicating cardiac catheterization with systemic thrombolytic therapy

Stent-mediated wedging of a calcific embolus to recanalize an occluded middle cerebral artery: technical case report

OBJECTIVE

Calcific cerebral emboli are rare yet pose a difficult therapeutic challenge because of their lack of response to thrombolytic therapy and their propensity for fragmentation.

CLINICAL PRESENTATION

A 75-year-old woman developed aphasia and hemiparesis after cardiac catheterization from a near-occlusive calcific embolus to the left middle cerebral artery origin. The calcific embolus was shown to be hemodynamically limiting by computed tomographic perfusion and diffusion-weighted magnetic resonance imaging.

INTERVENTION

The patient was treated medically for 6 days with anticoagulation, antiplatelet, and hypertensive therapies but continued to deteriorate. A decision was made to attempt retrieval of the calcific embolus. Conventional intracranial mechanical clot and coil retrieval systems were used initially but were unsuccessful and caused migration of the calcific embolus, leading to complete occlusion of the left middle cerebral artery origin. At this point, the decision was made to wedge the calcific embolus against the vessel wall. A balloon-mounted coronary stent was used to achieve this successfully, resulting in recanalization of the middle cerebral artery trunk and flow restoration.

CONCLUSION

Symptomatic calcific emboli, which are poorly responsive to pharmacological therapy and difficult to recover using conventional retrieval systems, may be treated by immobilization against the vessel wall using a balloon-mounted stent.

The safety and efficacy of thrombolysis for strokes after cardiac catheterization

OBJECTIVES

The purpose of this study was to systematically compare clinical outcomes of patients treated with thrombolysis with those without treatment in a multi-year, multicenter cohort of strokes after cardiac catheterization.

BACKGROUND

Ischemic strokes after cardiac catheterization procedures, although uncommon, lead to the morbidity and mortality of thousands of patients each year. Despite the availability of Food and Drug Administration-approved thrombolytic therapy for acute ischemic stroke since 1996, thrombolysis remains unestablished in the setting of cardiac catheterization, owing to unique concerns regarding safety and efficacy.

METHODS

Consecutive cases of ischemic stroke after cardiac catheterization were abstracted retrospectively and reviewed by clinicians at 7 major North American academic centers with acute stroke teams. Safety and efficacy outcome measures were pre-defined.

RESULTS

A total of 66 cases of ischemic strokes after cardiac catheterization were identified over 3 to 4 years; 12 (18%) were treated with thrombolysis, consisting of 7 intravenous and 5 intra-arterial recombinant tissue plasminogen activator cases. Improvement in stroke symptoms, as measured by the primary efficacy measure of median change in National Institutes of Health Stroke Scale score from baseline to 24 h, was greater in treated versus nontreated cases (p < 0.001). Additional secondary measures of efficacy also showed better outcomes in the treated group. There were no significant differences in bleeding events, defined as symptomatic intracerebral hemorrhage, hemopericardium, or other systemic bleeding resulting in hemodynamic instability or blood transfusions. Mortality rates were also similar.

CONCLUSIONS

Thrombolysis might improve early outcomes after post-catheterization strokes and seems safe in this context. Emergent cerebral revascularization should be a routine consideration.

Management of cerebrovascular accidents during cardiac catheterization

Ischemic cerebrovascular events are a rare complication of cardiac catheterization. Consequently a unique standard of management for these events is yet to be defined. Immediate cerebral angiography followed by local thrombolysis is an effective strategy and we report six cases for which this approach was successfully employed. In contrast the use of immediate neuroimaging by means of MRI or CT scan in two cases delayed the implementation of appropriate therapy.

Does diagnostic coronary angiography induce significant coronary microembolization in stable, ischemic patients? A prospective study

BACKGROUND

Although microembolization during percutaneous coronary interventions is a frequent event, the extent of possible microembolization during diagnostic coronary angiography is unknown. The aim of the study was to investigate whether diagnostic coronary angiography results in coronary microembolization and consequent subtle, subclinical myocardial necrosis with enzyme elevations.

METHODS

Fifty-three consecutive patients underwent diagnostic coronary angiography due to inducible ischemia. Creatine kinase MB isoenzyme (CK MB) and cardiac troponin I (cTnI) were used as sensitive surrogate markers of myocardial necrosis. Serial measurements, before, and 6 and 24 hours following a diagnostic procedure, were performed.

RESULTS

Baseline cTnI was below the limits of detection in all patients (<0.20 ng/mL), except for one patient with 1.31 ng/mL. Baseline median CK-MB was 1.05 ng/mL (interquartile range, 0.80-1.56 ng/mL) (Fig. 1). Both at 6 and 24 hours, no patients had any increase in cTnI, with the exception of a minor increase to 0.22 ng/mL at 24 hours in one patient. At 6 hours, 25 patients had decreases in CK MB, while 22 had increases (exact P = 0.77). At 24 hours, 26 patients had decreases in CK MB and 19 patients had increases.

CONCLUSIONS

Detectable embolization with subsequent subclinical myonecrosis is an unlikely event.