In 2008, representing 30% of all global deaths, a figure expected to rise to 23.3 million by 2030. According to SIGN (Scottish Intercollegiate Guidelines Nerwork). Risk Estimation and the Prevention of Cardiovascular Disease. A National Clinical Guideline. 2007 Report No. 97, CVD disability-adjusted life years (DALYs) are expected to rise from a loss of 85 million DALYs in 1990 to a loss of close to 150 million DALYs globally in 2020, thereby remaining the leading somatic cause of loss of productivity. A point of note is that over recent decades there has been a marked trend for a shift in the incidence of CVD away from Europe, with more than 80% of all CVD mortality now occurring in developing countries. This trend of course has profound implications for the topic discussed in this issue of Dialogues in Cardiovascular Medicine cardiovascular imaging in terms of how these countries will be able to cope with the high costs attached to cardiovascular imaging.
In addressing CVD, currently available drugs such as aspirin, angiotensin-converting enzyme inhibitors, statins, and fl-blockers are certainly useful: together they are estimated to account for a 30% reduction in cardiovascular mortality worldwide. This contrasts with the 5% to 10% reduction in cardiovascular mortality observed with more sophisticated reperfusion techniques. But this is probably mainly because these techniques are applied too late or to too few patients or are too expensive.
What this says is that, in spite of dramatic advances, treatment still falls short of achieving the expected goal and still has a long way to go. Thus, the battle against cardiovascular disease still has a lot more to do with prevention than treatment. This is where the sophisticated (and, once again, costly the reader will have to bear with our hammering this point in!) new imaging techniques come into the picture, such as: assessment of carotid intimal-media thickness as a surrogate of atherosclerosis, determination of coronary artery calcium scores by computed tomography. CT angiog raphy, detection of plaque vulnerability by invasive imaging modalities, or, more simply, echocardiography to detect early abnormalities in the cascade of the cardiovascular continuum.
The temptation grows even more irresistible in light of the recent European Guidelines on Cardiovascular Disease Prevention in Clinical Practice (2012). These guidelines no longer make the distinction between primary and secondary prevention, but refer instead to a gradual increase in cardiovascular risk independently of the presence of overt cardiovascular disease. For their patients at high or very high risk, cardiologists now have the means to determine the precise level of risk and fine-tune the treatment accordingly. As for patients at low or very low risk, as usual, when precise cutoff points fade away and turn into a continuum, the decision as to when and in whom apply such costly techniques tends to become an economic issue, hence very quickly a political one (for health services, doctors, institutions, cities, nations, policymakers, politicians, etc)
These techniques are undoubtedly helpful. But a few hard questions must be asked. Just how helpful are these techniques really, in terms of specific data not obtainable otherwise? In which patients should they be applied? And, more down-to-earth, is theiruse sustainable considering the increasing economic belt-tightening medicine is facedwith? Finally, are we not underestimating the risks of radiation associated with these techniques?
This latter point is relevant as official health regulators approve the use of such techniques not on the basis of their efficacy (as is the case for drugs), but solely of safety. No clinical trials are requested to prove the real advantages obtained by each technique, which leaves the decision to the individual cardiologist on when, how, and in whom to use them. This is the reason why the Editorial Board of Dialogues in Cardiovascular Medicine decided to produce this issue: to put the readers in the picture by reviewing the advantages and disadvantages of the new cardiovascular imaging techniques in order to help them make the right choice.