Clinical and angiographic correlates of cerebrovascular insufficiency

Prognosis of vertebrobasilar transient ischaemic attack and minor stroke

“…Thirty-one papers reported data from 26 independent prospective cohort studies or treatment trials, and 13 papers reported data from 10 independent retrospective cohort studies. Only six studies speci®cally intended to determine the prognosis according to the vascular territory of the qualifying event as one of their primary aims (David and Heyman, 1960;Drake and Drake, 1968;Acheson, 1971;Whisnant et al, 1978;Heyman et al, 1984b;Howard et al, 1987), two of which only reported the prognosis for overall mortality. Nine papers reporting data from six independent cohorts reported outcomes for individual patients who had events in both carotid and VB territories (Baker et al, 1968;Drake and Drake, 1968;Friedman et al, 1969;Ziegler and Hassanein, 1973;Cartlidge et al, 1977;Whisnant et al, 1978;Fieschi et al, 1981;Candelise et al, 1986;Keith et al, 1987).…”

“…However, we found no evidence for this. Secondly, differences in the prevalence of important risk factors could have in¯uenced the results, but few studies reported these data by the vascular territory of the presenting event and there were no consistent differences among the seven studies that reported sex and age by vascular territory of the presenting event (Drake and Drake, 1968;Olsson et al, 1976Olsson et al, , 1980Haerer et al, 1977;Simonsen et al, 1981;Heyman et al, 1984b;Ueda et al, 1987), and no differences in those studies that reported data on co-morbidity and risk factors (Olsson et al, 1976;Dyken et al, 1977;Fieschi et al, 1981;Simonsen et al, 1981;Heyman et al, 1984b). Moreover, the lack of a difference between patients with VB events and carotid events in overall mortality or in risk of coronary vascular events suggests that they had similar risk factor pro®les.…”

“…The widely held view that VB territory TIAs and minor strokes have a better prognosis than carotid territory events was supported by some studies of stroke risk (Siekert et al, 1961;Marshall, 1964;Baker et al, 1968;Drake and Drake, 1968;Friedman et al, 1969;Acheson, 1971;Ziegler and Hassanein, 1973;Herskovits et al, 1981a, b;Simonsen et al, 1981;Heyman et al, 1984b;Sivenius et al, 1991;Grotta et al, 1992), but not others (Acheson and Hutchinson, 1964;Baker et al, 1966;Friedman et al, 1969;Ostfeld et al, 1973;Cartlidge et al, 1977;Toole et al, 1978;Heyden, 1979;Heyman et al, 1982;Muuronen and Kaste, 1982;Wiebers et al, 1982;Candelise et al, 1986;Keith et al, 1987;Whisnant and Wiebers, 1987;Baumgartner et al, 1989;Sacco et al, 1989;Cillessen et al, 1993). However, most of these studies were small and did not have the statistical power to determine differences in prognosis reliably.…”

Protracted Transient Ischemic Attacks

“…The embolic theory of TIA is supported by the following data (van der Drift and Kok, 1971;Russell, 1976): (a) the attacks, always sudden, do not usually bear any relationship to postural variations, hypotension or cardiac abnormalities; (b) the episodes do not occur within the same district: according to Waltz (1978), however, a stereotyped behavior can be accounted for even by embolization; (c) em bolic sources can usually be identified; (d) emboli have been visualized during their pro gression within retinal vessels Russell, 1961, 1963, 1968\ Ashby et al, 1963Gunning et ai, 1964), and (e) no attacks can be brought about by even considerably lowering the blood pressure in patients who were cur rently experiencing TIAs (Loeb et ai, 1961;Kendell and Marslw.ll, 1963;Drake and Drake, 1968).…”