For the first time a very important government
medical authority ( Medicare) has declared that “ there is sufficient EVIDENCE
to conclude that Microvolt T Wave Alternans (MTWA) diagnostic testing is
reasonable and necessary for the evaluation of patients at risk of sudden
death, only when the spectral analytic
method is used..” Medicare went to say: “ MTWA is a useful risk stratification
tool and can identify which heart patients are at NEGLIGIBLE risk of sudden
death, and who may therefore be able to avoid ICD implantation and its
attendant RISK”.
EVIDENCE BASED MEDICINE are the key words in
clinical medicine so that MEDICARE for the first time takes this decision based
on an analysis of more than 100 papers (more than 2600 patients) on the subject.
The paper of Bloomfield (1) on JACC
2006 on other 587 patients and the Bavarelli heart failure paper in the
International Journal of Cardiology (2) were all published too late to be
included in Medicare analysis.
In the REAL WORLD of Medicine there are not sufficient resources to treat all the
patients with costly invasive therapy.
Recent events highlighting the potential
complications of ICD ( infections, ICD removal, leads removal, inappropriate
shocks ) make discussion between the physician and the patient more critical.
Often MTWA Abnormal results become the enabling event to convince an unwilling
patient that invasive therapy is needed, while an MTWA test can help to reassure both the patient and the doctor that
conservative medical therapy is most appropriate.
In Europe the budget for ICD implantation is
limited so that in most Cardiology department there is a fixed number of ICDs
to be implanted per year and the Doctor has to make a decision on which of his
MADIT II (or SCD-Heft ) type patients can he afford to implant an ICD.
In the REAL WORLD there is a problem of limited
resources and MTWA can provide the best solution.
1.
Bloomfield DM, Bigger, JT et al. MTWA and the risk of death or sustained
ventricular arrhythmias in patients with left ventricular dysfunction. J Am
Coll Cardiol 2006; 47:456-463
2 Baravelli , Salerno Uriate et al. Predictive
significance for sudden death of microvolt-level T wave alternans in New
York Heart Association class II congestive heart failure patients International Journal
of Cardiology ,Volume 105, Issue 1 , 20 October 2005, Pages 53-57