Antithrombotic Therapy for Cerebrovascular Disorders: Ventricular Aneurysm

An alternative approach to early anticoagulation of unselected patients with anterior AMI is to administer heparin only to those patients with LVT detected by echocardiography. Aggregate data, albeit from multiple small studies of disparate design, suggest that initiation of anticoagulation after detection of LVT may reduce the risk of early (1 month) embolism (Table 4). Most authors empirically recommend anticoagulation for several months when LVT is detected in the weeks following AMI, particularly if protrusion or mobility is present. Anticoagulation is usually recommended for 3-6 months, even if LVT persist. No clinical data are available about the efficacy of platelet-antiaggregation agents in prevention or treatment of LVT and embolism following AMI. Clearly, more reliable early predictors of embolism risk are needed. read
Ventricular Aneurysm
Previous retrospective studies of patients with LV aneurysms with or without associated LVT detected by cardiac catheterization remote from AMI reported low prevalences of emboli. Recent studies of the embolism risk of LVT detected echocardiographically have yielded apparently conflicting results (Table 5). Long-term follow-up of 144 LVT initially detected in the AMI period in 6 studies show a diminishing late embolic risk (Table 5): 6 of 7 emboli occurred 1-4 months after AMI, while only 1 occurred 4-12 months after AMI. Aggregate overview analysis of these 6 studies with mean follow-ups of 6-15 months show late emboli in 1% of 98 anticoagulated patients compared with 13% of 46 nonanticoagulated patients with LVT. In short, the data are inconclusive about the late embolic risk associated with LVT owing to availability of limited numbers of small studies with LVT detected at differing intervals and with nonrandom use of antithrombotic agents. In contrast to earlier studies based on catheterization-detected ventricular aneurysms, recent echocardiographic-based studies hint that LVT detected remote (1 month) from AMI may be associated with an increased risk of embolism, on the order of 5%/year. In 1 study of stroke in patients with LVT remote from AMI, 73% (11/15) were classified as cardioembolic in origin, while 24% were of uncertain etiology. There are no data about the efficacy of platelet-antiaggregation agents for primary or secondary prevention of embolism with LVT remote from AMI. If emboli are attributed to LVT, long-term anticoagulation is usually recommended for secondary prevention.
Table 4—Acute Myocardial Infarction, Ventricular Thrombi, and Early Embolism

Author/Reference	No.	Emboli, %
No anticoagulation
Domenicucci et al^m	52	10
Nordrehaug et al^m	7	14
Eiglen et al	3	0
Asinger et al	5	0
Weinrich et al	18	17
Keating et al^m	8	38
Turpie et al*	8	0
Aggregate	101	12
Anticoagulation before detection of thrombus
Arvan and Roscha”	4	25
Gueret et al	8	12
Visser et al	15	0
Friedman et al	9	11
Turpie et al*	10	0
Aggregate	46	7
Anticoagulation after detection of thrombus
Johannessen et al	15	27
Eigler et al^IM	4	0
Asinger et al	7	0
Gueret et al*	13	8
Arvan and Boscha*	6	17
Weinrich et al^u®	25	0
Keating et al*	9	0
Turpie et al	20	0
Aggregate	99	6

Table 5—Myocardial Infarct, Ventricular Thrombi, and Late Embolism

Reference*	Mean time of Detection	Follow-up	No.	% Emboli
Tramarin et al*	4 wk	11 mo
AC(-)			17	0
AC( + )			17	0
Keating et al*	2 wk	11 mo
AC(-)			5	60
AC( + )			9	0
Weinrich et al*	?l-3 wk	15 mo
AC (-)			14	22
AC ( + )			25	0
Asinger et al	2 wk	9 mo
AC ( —)			2	0
AC ( + )			7	0
Turpie et al	10 days	6 mo
AC ( —)			8	0
AC ( + )			30	0
Visser et al^m	2-3 days	12 mo
AC ( —)			10	10
AC ( + )			11	9
Aggregate		±12 mo
AC ( —)			46	13
AC ( + )			98	1

Category: Antithrombotic Therapy

Tags: antithrombotic therapy, cardioembolic source, cerebrovascular disorders