Even young people in good health can be the victims of cardiac arrest. Physicians need to compare a great number of patients and treatments to fully understand this phenomenon. This is the purpose of the European U-CARE register. Launched in 1992, this clinical data bank has already made it possible to draw some important conclusions.
The heart is the engine which powers our
bodies. All the substances which keep us alive (oxygen, nutrients,
hormones, etc.) circulate in the blood, which is itself regulated
by this essential organ. This vital function explains why impairment
of the cardiovascular system (involving the heart itself, but also
veins, arteries, capillary vessels, etc.) is involved in 50% of
The majority of cardiac arrests are due to ventricular fibrillation, meaning that the rhythm of ventricular contraction has been seriously disrupted. While medicine nowadays has made enormous progress in understanding the deficiencies of the cardiac system and in ways of remedying this, it still remains helpless in the face of a small number of sudden and sometimes fatal accidents (8%), which may concern young people in perfect health, with no apparent cardiac anomalies. This phenomenon, known as idiopathic ventricular fibrillation (IVF), is an immense challenge to physicians.
The register of unexplained cases
1992. Silvia Priori, cardiologist at the Institute
of General Clinical Medicine at the University of Milan asks for
help from the European Commission. Her objective is to carry out
a wide-ranging study (throughout the whole of Europe and for a period
of 10 to 15 years) to evaluate the effectiveness of medical care
given to patients with IVF. "Silvia Priori had already begun
collecting clinical cases and following them prospectively. But
rare diseases can only be studied through coordinated transnational
endeavours," explains her colleague, Dr Peter Schwartz, coordinator
of the project.
Thus, the Unexplained Cardiac Arrest Registry of Europe (U-CARE) was set up. Researchers began by establishing a statistical base from the detailed perusal of medical literature in the last 35 years. They discovered that, of the 125 reported cases of patients who had survived an IVF, 68% were males aged between 9 and 79 and were followed medically for a period lasting from two months to 14 years. 21% of them suffered a further cardiac arrest.
A particular patient profile
Now any physician can introduce data into the U-CARE register, provided that he can prove that it is a genuine case of IVF (no defects in the heart and arteries, normal resistance to stress, normal electrocardiogram, etc.) and that he can precisely establish the family history of the patient whenever sudden death has occurred.
On 20 January 1997, the register contained 172 detailed cases, 118 men and 54 women, the average age of whom was 39 when they had their first cardiovascular problem. Several conclusions can already be drawn: the majority of IVF victims are male and 29% of such patients suffer one or more additional attacks.
Conclusions have also been drawn as regards treatment. The most widespread remedy currently employed for IVF cases is the implantation in the heart of a defibrillator (a small device which delivers an electric shock if an attack occurs). It is estimated that this method of prevention saves up to 38% of people upon whom this operation has been performed. While this is a positive figure, it nevertheless still raises some questions.
"If we wish to evaluate the effectiveness of this device, we are forced to look at it from the other side and admit that 62% of patients have not derived any benefit from this costly system which, in addition, does not make life easy for patients," observes Dr Priori. "It is necessary, therefore, to pursue research to identify the risk factors of a new attack and to pinpoint those patients who would benefit most from the defibrillator. Of course, it is also necessary to continue trying to develop a drug which is capable of reducing the number of heart attacks."
Where medicines are concerned, unfortunately, studies carried out thanks to U-CARE have shown that the various treatments, which have been highly empirical as prescribed up until now, have not proven their worth: 28% of patients to whom drugs have been prescribed have suffered a new IVF and 8% have died as a result.
Project U-CARE is continuing. "The database has been set up and we intend to continue registering new patients and following them up each year," explains Peter Schwartz. "We are convinced that this approach of European investigation into IVF is vital. For the first time ever, this register provides clinical information for the follow-up of young individuals who suffer from repeated cardiac arrests and yet do not seem to be suffering from any apparent defect of the heart."