My understanding is as follows:
It is sensible to consider general co-morbidity in the decision to
thrombolyse (as mentioned in my previous posting), because this increases
the risk of complications following thrombolysis. For example, patients with
a previous CVA, GI bleed, etc. may be more at risk of bleeding
complications, as may those on anticoagulants, particularly warfarin.
Persons hypertensive at the time of presentation are also at a much higher
risk of intracranial bleeding.[1]
In many respects, age is simply acting as a marker for such co-morbidity,
but there is also some evidence that older persons have a higher excess
mortality following thrombolysis that may be directly related to sudden
cardiac rupture, rather than the usual bleeding complications.[2] The
cardiac surgeons say that when you open the chest of an 80 year old, the
heart looks 80 years old, regardless of how the patient appears on the
outside (I'm afraid I have no evidence to support that one!)
Cardiac morbidity, such as heart failure and poor exercise tolerance, may
favour the administration of thrombolysis. Patients with poor cardiac
reserve, and those who are in failure or hypotensive on admission, have
potentially the most to gain, because they may not be able to survive
without the heart muscle that is currently infarcting. This is likely to be
the reason why infarcting patients who have bundle branch block gain even
more benefit from throbolysis than those with an anterior MI (NNT to save
one life = 21)[3]
The more you study this, the harder the decision gets!
Regards,
Jonathan Benger.
SpR, Bath.
1. Selker HP, Griffith JL, Beshansky JR et al. Patient-specific predictions
of outcomes in myocardial infarction for real-time emergency department use:
a thrombolytic predictive instrument. Ann Intern Med 1997;127:538-556.
2. Thiemann DR, Coresh J, Schulman SP, et al. Lack of benefit for
intravenous thrombolysis in patients with myocardial infarction who are
older than 75 years. Circulation 2000;101:2239-2246.
3. Gallagher EJ. Which patients with suspected myocardial ischemia and left
bundle-branch block should receive thorombolytic agents? Ann Emerg Med;
2001:439-444.
-----Original Message-----
From: Accident and Emergency Academic List
[mailto:[log in to unmask]]On Behalf Of Adrian Fogarty
Sent: 16 October 2002 00:19
To: [log in to unmask]
Subject: Re: Thrombolysis and previous surgery
Don't you need to take morbidity into account; you know, heart failure,
exercise tolerance and the like?
AF
----- Original Message -----
From: "Jonathan Benger" <[log in to unmask]>
To: <[log in to unmask]>
Sent: Tuesday, October 15, 2002 2:27 PM
Subject: Re: Thrombolysis and previous surgery
> >From the FTT review (1):
>
> Numbers needed to treat with thrombolysis (to save one life):
> Anterior MI: 28
> Inferior MI: 120
>
> Numbers needed to harm with thrombolysis (to cause one death):
> ST depression: 72 (the relation of this to posterior MI is unclear)
> Normal ECG: 144
>
> The 95% confidence intervals of the NNT in inferior MI overlap with those
> for the NNH in normal ECGs. This is not the case for anterior MI, and the
> difference is quite striking.
>
> Therefore, the location of the MI should be taken into account (along with
> age, co-morbidity, sex, warfarin use, recent surgery, bleeding risk, etc,
> etc) when considering the risk/benefit ratio for each patient eligible for
> thrombolysis.
>
> Regards,
>
> Jonathan Benger.
> SpR, Bath.
>
> (1) Fibrinolytic therapy trialists' (FTT) collaborative group. Indications
> for fibrinolytic therapy in suspected acute myocardial infarction:
> collaborative overview of early mortality and major morbidity results of
all
> randomised trials of more than 1000 patients. Lancet 1994;343:311-322.
>
> -----Original Message-----
> From: Accident and Emergency Academic List
> [mailto:[log in to unmask]]On Behalf Of Goat
> Sent: 13 October 2002 20:59
> To: [log in to unmask]
> Subject: Re: Thrombolysis and previous surgery
>
>
> I couldn't remember where I had heard this. Thanks for reminding me,
> Rowley.
>
> When I saw the original post, I went on the hunt for any guidelines on
> the web differentiating between inferior and anterior MI for lysis - got
> zip. Our Trust guidelines don't differentiate between MI sites for
> lysis.
>
> Is this one of those cases where the "evidence" has been over-sold?
>
> Which of the many lysis trials can we get such info from? I coudl find
> nothing on a quick title search on medline this pm.
>
> Yes, you're right Rowley, I am just too lazy to look further myself, or
> is it just too tired! Throw me a bone!
>
> Goat
>
>
>
> In article <[log in to unmask]>,
> Rowley Cottingham <[log in to unmask]> writes
> >Um, there is no evidence that thrombolysis affects the outcome in
inferior
> MIs,
> >you know.
> >
> >Best wishes,
> >
> >
> >Rowley Cottingham
> >
> >[log in to unmask]
> >http://www.emergencyunit.com
>
> Dr G Ray
> A&E
> Sussex
> Reply to [log in to unmask]
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