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Is the new professionalism and ACP's new ethics really just about following guidelines?

The Charter ( Medical Professionalism in the New Millennium.A Physician's Charter) did not deal with just the important relationship of ...

Tuesday, September 29, 2015

New and better ways to distinguish "athlete's heart" from abnormal heart enlargement

It has been long recognized that athletes may have larger hearts and changes on the EKG that are difficult to distinguish from abnormal findings such as those seen in an abnormally enlarged and thickened  left ventricle with hypertrophic muscles as is seen in long standanding hypertension.

In fact athletes have enlarged heart muscle as well and cardiologists have attempted to provided some wall thickness values above which it is thought to be too big to indicate the physiologic increases in muscle and chamber size of the athlete and represent pathological and maladaptive muscle growth. A distinction  based on various  EKG criteria have never been that reliable.

In addition, all athletic activity does not seem to bring out the same type of physiological adaptive changes. A distinction is typically made between endurance athletes and strength athletes, recognizing that some athletes do both endurance and strength training.

Generally endurance athletes increased cardiac output under conditions of  reduced peripheral resistance while strength trained athletes increased cardiac output against increased peripheral resistance. It would not be unexpected that these difference would be reflected in the heart's adaption

The stylized facts are that  the endurance athletes have increased wall thickness  as do the strength folks but endurance athletes have larger chambers . e.g left atrial size and left ventricular diastolic diameters. The usual definition of the upper limit of normal for the left atrium is often said to be 35ml while one  study of endurance athletes has shown value of 37.7 ml.The left  ventricular wall is sometimes greater than 13 mm ( in one study of elite endurance athletes 13% were greater than 13 but none above 15 mm.  About 1/3 of elite endurance athletes have LV cavity end diastolic greater than 60 ml. whereas  upper  normal is typically consisted 55 ml Typically endurance  athletes are said to have eccentric hypertrophy while endurance athletes have concentric but that concept has  been challenged.

At least one study reported that endurance athletes had indicators of  better diastolic function that do strength trained athletes. (Vinereanu,D, Clin Sci 2002).However, overall the data are conflicting as to whether endurance exercise improves diastolic filling apart from  heart rate changes and
 as to whether any diastolic function improvement persists in senior athletes to significantly mitigate the seemingly universal age related increases in myocardial stiffness. ( Perhaps another example of the Woody Allen physiological maxim ,paraphrased when you get old everything  that should be soft gets hard and everything that should be hard gets soft.)

In any event the athletes hearts seems to work quite well particularity when compared with the enlarged heart s that can results from hypertension both in terms of pumping  the blood during systole but also  in rapidly refilling the ventricular chamber in diastole preparatory for the next ejection

Athletes hearts  pump more effectively  blood during systole This is   usually expressed as as EF, value ( ejection fraction) which is  generally greater in endurance athletes than in  normals but the range overlaps. .But also the athlete's  ventricles  fill faster in the relation phase of the left ventricle , i.e. diastole so their enhanced cardiac output results from more filling  and more ejection giving them higher stroke volumes.

Using various indicators of diastolic function ( such as the early phase of filling versus the later phase of filling (an e/a ratio being one such measure) it has been  clearly demonstrated that left ventricular filing is normal or supra normal in the endurance  athletes with increased wall thickness while the opposite occur to varying degrees in hypertensive heart disease and other causes of LVH such as aortic stenosis and hypertrophic cardiomyopathy .

Newer echo techniques have provided even more evidence of a distinction   between the enhanced  cardiac function of the endurance trained athletes and those with hypertensive heart disease and to aid in the differential diagnosis of hypertrophic cardiomyopathy.

In the last ten years a technique referred to as deformation imaging ( which can be subdivided into 1)TDI and 2)speckle-tracing 2D strain imaging  has provide a new way to elucidate cardiac physiology. The techniques can distinguish between active and passive myocardial segment motion.

In echo speak "strain" mean deformation, unlike the  everyone day English language meaning of stretching and these techniques measure strain and strain rate.Strain is considered the fractional change in length of a myocardial segment and can be expressed as a percentage.Ultra sound images contain natural acoustic markers, called speckles, which can be tracking as muscle segments move during contraction and relaxation and actively contracting muscles segment can be distinguished from areas moving poorly. 

Speckle tracing studies have shown that the ventricular hypertrophy as in  hypertension is associated with decrease strain ,that is less deformation, which is functionally disadvantageous while the hypertrophy of endurance athletes does not differ appreciably from normal controls and is not associated with  functional impairment.In other words this is  an advantageous remodeling.

A similar distinction between pathological left ventricular hypertrophy and  physiologic athletic hypertrophy  has been made using MRIs of the heart. ( Peterson SE, 2005 , J Cardiovas Mag Reason 2005:7,(3) 551. Speckle tracing is much less expensive .

For the most part newer testing techniques have done away with concerns about exercise causing the heart to enlarge in a deleterious physiological way with the interesting possible exceptions of  harmful changes or remodeling of the right ventricle and of the left atrium with a putative inceased risk of atrial fibrillation. Several authors have argued and provided some evidence that prolonged endurance type exercise can bring about a condition similar to an inherited disease called arrhythmogenic  right ventricular hypertrophy (ARRV), a topic I wrote about before see here.

addendum: added 10/1/15 5:46 PM.  Here is more on the differences between strength athletes and endurance athletes. Rowers were compared with Long distance runners and the authors fond  that the runners had larger left ventricular volumes,lower and in the normal range for ventricular mass and a tendency to less thickened left ventricular walls.  (Wasfy,M Endurance exercise-induced cardiac remodeling: Not all Sports are created equal,Journal of the American society of echocardiography, 2015,Sept 9


addendum 2/9/16. Minor wording changes made in last paragraph.
 


Thursday, September 03, 2015

George Soros's Open Society Institute and American Board of Internal Medicine Foundation programs,strange bedfellows or birds of a feather?

Medical Professionalism for the new Millennium; A Physician's Charter was published in 2002 both  in the Annals of Internal Medicine and in the Lancet reflecting an international authorship. In 2003, George Soros's Open Society Institute founded a think tank, advocacy organization called Institute on Medicine as a Profession. (IMAP) with a 7.5 million dollar grant.

Later two grants ($350,000 in 2003 and $ 60,000 in 2008) was  given to IMAP by the ABIMF.ABIMF is chiefly funded by the ABIM and has a common leadership roster.In turn ABIM makes its money by testing internists and managing their Maintenance of Certification (MOC) program,a program that has generated a firestorm of protests from practicing internists and a serious effort to establish a rival means of maintenance of certification.

What is the ACP-ABIM(F) version of medical professionalism. Among other features, this "charter" calls for physicians to be "stewards of society's medical resources" and to work for social justice. It speaks of an obligation not only to the patient but to society as least in the sense of conservation of these allegedly common resources and to work for a just distribution of these resources.

The Charter was not cut from whole cloth, neither was it a tailored answer to the alleged problems that were claimed to be causing physicians angst  in the new millennium.Rather it was another manifestation or application of the new Bioethics about which Pope Benedict XVI had this to say in his 2010 address to the Pontifical Academy for Life:

"Under traditional medical ethics the guiding principle is 'do no harm". But contemporary bioethics abandons this in an effort to find the utilitarian goal of the greatest good for the greatest number Under these principles preserving the life of the human patient is not considered paramount."

Wait. what  does the charter have to say about greatest good for the greatest number? Explicitly it said nothing but advocating social justice.

Social Justice is a loose , vague and indeterminate term, which although it has a useful rhetorical value   might puzzle physicians as to how they might actually work for the nebulous social justice in their everyday practices. The ABIMF in its publications and on its website made it explicit -follow the guidelines. In that way they claim  resources would be wisely distributed and fairly  thus furthering social justice. Here we get the greatest good for the greatest number in the collective. The collective may just be the HMO or ACO or possibly all members of society.So while the Charter seems on the surface to be medical ethical Principlism , a la Beaumont and Childress, underneath there is a strong utilitarian initiative .

ABIMF's mission appears to be to further this brand of medical professionalism and to
champion the "Choosing Wisely" initiative.

 The Soros funded IMAP describes its mission in the following way:
Their vision of medical professionalism  embodies 4 values;

1) altruism that is a unwavering commitment to the patient.
2)Physician Self regulation
3)Maintenance of technical competence-a commitment to life long learning
4)Civic engagement "Physicians should enlarge their scope of concerns from the welfare of the individual patient to a concern for the welfare of all patients" ( my underlining)

This parallels the outline of the Charter which continues to speak of duty to the patient but an additional obligation was grafted on to that traditional prime directive namely to conserve resources and work for an efficient and fair distribution of resources.Numbers 1,2, and 3 add nothing to traditional medical ethics but number 4 is another matter.

So IMAP more or less recapitulates the Charter blending the traditional mom and apple pie medical ethics with a new obligation to work somehow for all patients.It should be no mystery why ABIMF might share some of its resources with another advocacy group with similar if not identical goals. My question is why does Soros wish to promote the new professionalism i.e. the Charter ?

So here it is- the physician's goal should not just be the welfare of her patient but rather the welfare of everyone.And the best way she could accomplish that goal is to follow guidelines which will provide the best bang for the buck (efficient "parsimonious care") .And one way to save money is  to limit care to the elderly which is being sold as improving the quality of life in folks in their twilight days and months.

One of the leaders in the effort to limit care to the elderly , Dr.Joanne Lynn,perhaps said more that she intended when she said:"Not only the right thing to do, it makes good business sense".

Good business sense, is that what Choosing Wisely is all about?And whose business are we talking about.


 Addendum: 4/1/16 Minor changes in wording made.