I know you aren't asking for advice, but IF you have extra time I personally probably would also check pubmed for more recent studies, even tho the AHA hasn't updated this, many of the studies used are from the 70s and 80s. Since you can usually find 1 study proving any point you want to make, I try to read several to get an idea of what the majority of the studies show, but then again, I have lots of spare time.
Some of the info in the article I found a little puzzling like when they compared home testing to coumadin clinics and doctors offices, it said
"In the first study, 75 patients with prosthetic heart valves who managed their own therapy were compared with a control group of the same size managed by their personal physicians.147 The self-managed patients tested themselves approximately every 4 days and achieved a 92% degree of satisfactory anticoagulation, as determined by the INR. The physician-managed patients were tested approximately every 19 days, but only 59% of INR values were in therapeutic range. Self-managed individuals experienced a 4.5% per year incidence of bleeding of any severity and a 0.9% per year rate of thromboembolism, compared with 10.9% and 3.6%, respectively, in the physician-managed group (P<0.05 between groups)."
So even tho the self testers had less bleeds and clots than doctors office, at 4.5% compared to almost 11% bleeds, I would think the fact the self testers were checking their INR every 4 days while the doctors office were checked every 19 days, would probably (IMO) play a part in why the self testers were in range more often and so had less "events"
FWIW What I could find about the Dutch study you mentioned I think you were talking about this
"A retrospective study of 16 081 patients with mechanical heart valves in the Netherlands attending 4 regional anticoagulation clinics (target INR 3.6 to 4.8) found a sharp rise in the incidence of embolic events when the INR fell to <2.5, whereas bleeding increased when the INR rose to >5.0.120 "
I don't know if it was a typo but when I went to the study http://www.nejm.org/doi/pdf/10.1056/NEJM199507063330103
it was based on 1608 patients not 16,081.
"Results. A total of 1608 patients were followed during
6475 patient-years. Cerebral embolism occurred in 43 patients
(0.68 per 100 patient-years) and peripheral embolism
in 2 (0.03 per 100 patient-years). Intracranial and
spinal bleeding occurred in 36 patients (0.57 per 100 patient-
years) and major extracranial bleeding in 128 (2.1 per
100 patient-years). The optimal intensity of anticoagulation,
at which the incidence of both complications was lowest,
was achieved when the INR was between 2.5 and 4.9.
Conclusions. The intensity of anticoagulant therapy
for patients with prosthetic heart valves is optimal when
the INR is between 2.5 and 4.9. To achieve this level of
anticoagulation, a target INR of 3.0 to 4.0 is recommended."
But it also might not be that helpful, since many of the valves they were studying aren't used now.
the patients had 53 Caged ball or disk , 1354 Tilting disk, Bileaflet 347, Unknown 12
My guess would be the chances of clot with a bileaf valve would probably be less.
editted to add I wanted to add the breakdown of the valves for anyone interested
for the 53 caged valves -Starr–Edwards in 46 and Cooley–Cutter in 7.
for the 1354 tilt disk - Bjork–Shiley in 1052, Sorin in 164, Medtronic–Hall in 137, Lillehei–Kaster in 1.and of the bileaf valves - St. Jude in 242, DuroMedics in 56, and CarboMedics in 49
Also later on in "differences in subgroups", they show
"The overall incidence of thromboembolism was 0.5 per 100 patient-years for the bileaflet valves, 0.7 per 100 patient-years for the tilting-disk valves, and 2.5 per 100 patient-years for the caged-ball and caged-disk valves. The type of valve did not affect the risk of bleeding substantially."
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