by Shaffin Siddiqui
While it may be considered a platitude, the objective of medicine – in addition to actually administering hands-on care – is to pursue the path of treatment that minimizes long-term harm. Hence, the role of the doctor is not to simply slice and dice, but also to advise a patient whether to undergo the risky route of an invasive operation in the first place. Should one undergo the arduously invasive procedure of receiving a pacemaker for a heart chronically prone to arrythmia or settle for the less onerous alternative, albeit less bulletproof, alternative of oral treatment? The dilemma is often times acute, yet how often is it that this gradient of risk is assessed with the scruple it deserves…?
This past summer I had the privilege of conducting clinical research in the field of cardiology with Dr. William Roberts M.D[DS1] . at Baylor Scott and White in Dallas, Texas. With his guidance, I investigated replacement of the aorta in patients with congenitally abnormal aortic valves. Most individuals are born with normal three-leaflet (tricuspid) aortic valves which are located at the juncture of the left ventricle and aorta, from which oxygenated blood flows to the rest of the body. However, 1% of the American population is born with two-leaflet (bicuspid) aortic valves. In early cardiology, being born with these valves was strongly associated with aortic dilation (also given the scarier and more provocative label of “aortic aneurysm”) during one’s adult life. While bicuspid patients tend to see highest incidences of aortic dilation, many with normal valves experience idiopathic (i.e. random) dilation as well. Researchers[DS2] and doctors believed that the more dilated an aorta from its normal size, the more likely it was to crack open (i.e. dissect) or even rupture fully – incidents, both of which, are acutely painful and potentially fatal.
If aortic dilation is detected even in mild amounts, especially in patients with bicuspid aortic valves, surgeons insist that patients preemptively opt for an elective surgery to replace their dilated aorta in order to prevent the incidence of dissection/rupture in the future should it dilate even more. The thought of an aorta slowly expanding and popping, like a balloon, is terrifying to both physician and patient. Even if a surgeon happened to be performing cardiac surgery for another “neighboring” issue and incidentally noticed the patient had aortic dilation, many would subsequently replace the aorta in addition to the initial operation intended.
However, recent clinical data (~2007 onwards) has contested the need to categorically replace dilated aortas. Some aortas are so enlarged that it goes without saying that they deserve the title of aneurysm and need to be replaced. But, even then, rates of aortic dissection across the most frequently occurring sizes of dilation were shown to be exceedingly low. As well, rates of aortic expansion (i.e. how fast an aorta dilates) were shown to be quite low – if not, negligible – reducing the need to panic to preempt disaster. Even more strikingly, patients with bicuspid aortic valves were shown to be equally at risk for dissection/rupture as those with normal valves if given the same degree of dilation. Bicuspid patients, who had their aortas replaced the most frequently, had nothing to fear more than a patient with ordinary valves.
Given the data, one would think surgeons would be more deliberate in their decision to remove dilated aortas, especially with the operational risk associated cardiac surgery and specifically aortic replacement. Yet, my time at Baylor with Dr. Roberts, a cardiac pathologist – who looked at excised cardiac tissue post-operationally – showed me something quite different: countless pieces of functional heart tissue that were excised seemingly needlessly, and the most frequent organ amongst them: mildly dilated aortas. Indeed, the majority of the time the tissue was macroscopically and microscopically normal! As someone who has personally suffered from the tragedy of superfluous invasive operation, I was appalled. What could be behind this? For one, some CT surgeons are just not up to date on the data, and, to their credit, these studies are fairly new. Nonetheless, surgical practices should be in tune with changes in literature, especially when there is so much at stake, as with cardiac surgery. The bigger catalysts, however, seem to be more pecuniary: cardio-thoracic surgeons are paid by the operation, not by a fixed salary. As such, like it or not, there are incentives to operate on pathologies, even if they are likely benign for the patient. These operations are often elective, meaning the patient can opt out. When physicians, however, throw words like “aneurysm” onto the table, patients have a proclivity to panic. As such, combatting the tendency to needlessly operate requires a fundamental shift in health policy. While fixed salaries may be a somewhat tenable solution, this is an issue in health care that requires more awareness and the serious thought of health-care officials.
The views expressed in this article are mine alone, and do not express the opinion of the Princeton Public Health Review.