Sir,
S J Leslie, L P Paudyal, N R Grubb, M A Denvir
Department of Cardiology Cardiology, Lothian University Hospitals Division, Edinburgh UK
Corresponding author: Stephen J Leslie Email: s.j.leslie@ed.ac.uk
SMJ 2005 50(4): 179-180
There is increasing evidence to support the use of cardiac resynchronisation therapy (CRT) in patients with heart failure.1-5 In the most recent study CRT reduced mortality by 36%.5 Furthermore, recent NICE guidelines have stated that:
‘Resynchronisation therapy should be considered in selected patients with left ventricular systolic dysfunction (left ventricular ejection fraction <35%), drug refractory symptoms, and a QRS duration >120 ms.’.6
Currently, the use of CRT is limited by both financial constraints within the NHS and a lack of suitably trained cardiologists. Using a clinical CHF database we have attempted to estimate the costs of implementing the findings of recent trials in our heart failure population and we have extrapolated these figures to Scotland.
Our local heart failure database contains details of 750 patients with a diagnosis of heart failure managed within two university hospital centres (population 400,000). These patients were entered into the database at the time of their contact with secondary care. The prevalence of heart failure in Scotland was recently calculated as 0.7%.7 Thus, we would expect to find around 2800 patients in our area with heart failure, our database population therefore represents about 25% of our heart failure population.
Of the 750 CHF patients in our database, 290 (39%) are graded as III/IV. ECG data were available on 201 (69%) grade III/IV patients. Of these, 56 (28%) had a QRS width >130 ms and 84 (42%) had a QRS width >120 ms, which is similar to other heart failure populations,8-10 suggesting that our dataset contains patients representative of the wider CHF population. All of the class III/IV patients are assumed to have an ejection fraction of <35% on the basis that their echocardiogram is reported as showing moderate or severe left ventricular impairment.
Recently published trials of CRT have relied on a clinical diagnosis of heart failure, simple echocardiographic confirmation of LV systolic impairment and a QRS width >130 ms3 or >120 ms.1,4,5 Thus, allowing for those with missing ECG data, this would suggest that 122 patients in our cohort have met the criteria for CRT according to the COMPANION trial4 and 81 patients according to the MIRACLE trial.3
Extrapolating from our dataset, we estimate in our managed clinical network region that between 306 and 425 (11- 15%) patients would fulfil recent trial criteria for cardiac resynchronisation therapy. In other series, this figure has varied between 3.7 and 10% in other populations.11,12 The larger proportion of patients may be due to over representation of patients with more severe heart failure given that they were entered into the database only after a point of contact in secondary care.
Estimated costs for CRT are shown in Table I. The total potential cost per patient is approximately £6,121 in the first year (~£4,000 per device). CRT for all prevalent CHF cases identified within our regional database would cost somewhere in the region of £2 million. Extrapolating to Scotland (population ~ 5 million) yields figures of between 3850 and 5250 prevalent cases of CHF patients that may benefit from CRT. The total cost for treatment of the prevalent CHF population with CRT would therefore be between £23M - £32M. Clearly, not all of these patients are likely to be identified as many will have been discharged from follow up and a proportion may have other comorbidities which may preclude pacing. The costs in subsequent years for incident cases would be considerably less. In our database, 192 new patients were identified in 2004, with 30 of these likely to fulfil the current criteria for CRT resulting in an annual cost of over £180,000 in Lothianh, £2.3m nationally. However these costs do not consider the additional costs of combined CRT and implantable defibrillation devices which may be indicated in certain patients.
While there may ultimately be cost savings from reduced morbidity and hospitalisations in CHF patients receiving CRT the initial cost implications for this therapy are considerable. Further discussion regarding funding and patient selection is urgently required on a national basis to insure equity of access for patients to this potentially life saving therapy.
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