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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 ...

Wednesday, February 01, 2023

The unexpected relationships between both high dose statins and high level endurance exercise and coronary calcification

 The jury  has been back for a quite a while. Statins decrease the risk of coronary artery events. The curvilinear relationship between exercise and coronary artery events is also apparently beyond debate.

So one would not predict that both statins and exercise could be too much of a good thing in regard to coronary artery disease. Remember coronary calcification is, by defintion,coronary artery disease. 

There are ample data demonstrating that long time and high dose statin use  may increase the development of coronary calcification.In addition,there are reports of increased coronary calcification in long time marathon runners and endurance athletes. 

So,how does this work? Exercise at least  up to some level (that  level has yet to be defined) decreases CAD risk but at some level increases coronary artery calcification which is a marker of CAD. Is the calcification different in endurance athletes? There is evidence that in endurance athletes who have coronary calcification that there are more of the dense variety and less of the mixed type which is thought to be more likely to thrombosis. 

Can internists keep up with medicine

 I have sampled four internists , two in active practice two retired more than 10 years earlier.Perhaps we can excuse the ignorance in the retirees.

All were woefully ignorant about the basics of the most common cause of anemia in the world,Iron deficiency anemia (IDA).

Case in point. A 78 year old man is noted to have a decrease of more than one gram in his hemoglobin from the previous annual "wellness meeting" which should not be confused with the annual physical exam which at least for some perhaps many Medicare patients is a thing of the past.Medicare will pay for an  annual wellness visit but not a real hands on physical exam.  The internist who  practiced in a practice group associated with a large "not for profit" hospital system recommend he take ferrous sulfate three times a day,

Note- there was not at the time a recommendation for the patient to have a GI tract evaluation, not even a stool Guiac was mentioned. In 2019 a influential often quoted article by Ganz and Weiss included a flow sheet indicating that older patients ( over fifty) undergo a upper and lower endoscopy to rule out a source of bleeding if their initial blood tests has a pattern consistent  with ( but not necessarily diagnostic of ) iron deficiency anemiaThe patient 's blood test fit that pattern. This  pattern was low serum iron and percent saturation and a ferritin less than 100. Possible iron defeciency anemia in a man over fifty certainty warrants an evaluation for GI tract bleeding.

As the case evolved the GI doc's ignorance re IDA was revealed when he commented that a subsequent increase in the patient's ferritin reflected increasing iron stores. These two internists apparently knew little or  nothing about the iron regulating hormone,hepcidin,   If they did they would know how to administer oral iron and how to use the ferritin  ( and other tests suh as the Ferritin index )to help differentiate between IDA and anemia of chronic inflammation and their combination.

Medicare Wellness Visit will not detect early disease but it is quick easy money for internist

 For the past five years I have taken part in a version of the Medicare Wellness Visit with the addition of a series of blood tests.During that time a thyroid cancer grew to the size of a very large egg ( 5.5 cmX 3.5X 3.5) before it was finally detected from a cervical spine CT. Medicare Wellness exam is reimbursed by Medicare reasonably well but Medicare does not pay for physical exams

My medical " care " during  a nine month period during which I was ostensibly  being evaluated for a mild anemia is notable for the following:

1.The entry of a number of errors in my medical chart ( which is recorded in a widely used electronic health record (EHR) My diagnosis included atrial fibrillation and diabetes neither of which do I have.The EHR continues  to admonish me that my diabetic eye exam  and diabetic foot exam are  overdue.

2.The ignorance of my primary care doctor and a GI specialist  in regard to the diagnosis and treatment of  the most common anemia in the world namely iron deficiency anemia was not reassuring. Both of their  knowledge gaps could have been quickly corrected  by spending a few minutes accessing Up T0 Date on their  electronic device.

3.The alarmingly long time lag between various elements of my diagnostic workup which took place in a nationally known and highly ranked medical care system AKA hospital system. For example from the time my  thyroid cancer was diagnosed by a fine needle aspiration (FNA) until the day of surgery was 43 days.

4.Entries in my record of several "phantom" medical exams. By phantom I mean description of exams that were in fact not done but still attested to by the physician's electronic signature. Why do some many physicians put their signature to a cut and paste exam that was not performed? Do they know what they will say if asked at a future deposition 'Doctor, did you actually do a exam on Mr.Jones on such and such date? Do you routinely lie on the medical record? .During a nine month period I was seen in the office by physicians 8 times and none of them apparently even looked at my neck let alone felt my thyroid gland  though on several occasions a normal thyroid exam was recorded in the chart  ( ie. the phantom exam).

5.My bone marrow aspiration and biopsy was done by a NP who told me she had been taught the procedure by a hematologist only some several  months earlier. A noteworthy thing about the BM exam was the price charged ($ 23,000 ) by the hospital.

6.The thyroid mass was detected by a CT of the cervical spine ordered by a neurologist who never did notify me of the abnormality. Fortunately I was able to access the report and read of the finding myself. An earlier chest CT report did not mention a thyroid mass although it was clearly visible. 

7.Astonishingy an ENT specialist who did a fiberoptic office exam of my throat for evaluation of a cricopharyngeal bar recorded a normal neck exam including the comment that the thyroid was free of nodules did not  perform an exam of the thyroid at all. One week later the cervical CT showed a thyroid mass 5.5 cm in its largest dimension. I had to wait 6 weeks for that ENT appointment.

8.The pathology report of the surgical specimen of the thyroid tumor has a number of syntactical and transcription errors,likely representing inconsequential errors but IMO reflecting an alarming lack of proofing and professionalism.

(9 The attending surgeon and the consulting endocrinologist both  either misread the pathology report or did not understand the significance of the reported findings and both told me that it was a very low risk variation but after the case was presented to the tumor board both amended their evaluation and recommendations accordingly based on the microscopic findings.

Iron deficiency is common in endurance athletes

 Iron deficiency is common in strenuous exercise i.e in  endurance athletes.

In runners "GI iron loss"is frequently mentioned as a possible cause of the iron deficiency frequently observed in runners but those publications rarely describe or explain exactly what they mean by GI  iron loss. 

Do they mean that the incidence of well recognized causes of GI bleeding (colon cancer,polyps,peptic ulcer etc) are common in runners. I find little evidence of that.Perhaps the reference is to some  type micro bleeds. Or do they mean there is some physiological mechanism by which there is GI iron loss without gross GI bleeding  namely occult GI bleeding ( ie. normal stool color with a positive hemoccult test).

Actually there are data indicating occult GI iron loss  with at least  one  study with positive  guaiac tests post marathons and another  pre and post marathon  upper endoscopy study showed some small lesions in the stomach that could possibly cause small amount of blood loss.

There is a physiologic mechanism by which runners ( and other endurance athletes) loose blood in the GI tract.The mechanism is the sloughing off of iron loaded duodenal luminal lining cells (aka enterocytes) Actually this is a physiologic process that happens in everyone but is believed to be significantly increased in endurance athletes particularly runners because they may have more exercise induced hemolysis which in turn leads to more iron loss due to duodenal cell sloughing which is intensified by hepcidin release for exercise which traps the iron in the duodenal cells and the macrophages. Enteroyctes have short ( about 3 day) life span.

Here is an "as if"  story of how that might work. Strenuous exercise leads to the release of IL6 which in turn stimulates the release of hepcidin, the hepatic hormone that is the master regulator of iron absorption and transfer and storage. (The putative release of hepcidin by IL6 is not crucial to  the story  it is the release of hepcidin that is important ).Hepcidin blocks the release of iron from the enterocytes and from macrophages slowing down the transfer of recycled iron to the bone marrow. 

  The Assocation of iron deficiency and running is well discussed in the sports medicine literature and in the lay runners press but much less so the hematology journals.

Tuesday, January 31, 2023

Are the Strauss criteria for diagnosis of LBBB best to predict outcome of CRT

 Are the Strauss criteria for LBBB diagnosis best suited to predict favorable outcome for CRT ?

Jastrzebsi et al have published data suggesting that the answer to that question is yes. The authors compared four EKG criteria for the diagnosis for LBBB and then compared the outcomes of CRT of patients defined as having LBBB by the various criteria. Patients with Strauss defined LBBB did better than the patients with LBBB defined by other criteria.

This study supports the notion that LBBB defined by Strauss detects so called "true LBBB" with delayed activation of the lateral left ventricular wall and the abnormal inter-ventricular septum motion which can be detected by the "septal flash" on cardiac echo exam. In other words the Strauss EG patterns seems to detect patients whose conduction defect(s) is most likely to be corrected by CRT differentiating it from various  "non-specific intraventricular conduction defects".

Jastrzebski,M et al Comparison of fojr LBBB definitions for predicting morality in patients receiving cardiac resynchronization therapy. Ann Noninvasive Electro 2018 23 (c) e 12563

Smart phone apps for Medtronic pace makers good for patient?or good for company?

 My pace maker battery life is on the downslope  of available electrons.This week I had an in office PM interrogation and the company tech took the opportunity to promote their new option ( for some units) namely an app for a smart phone to replace the bed side transmission unit I have now. 

I personally believe the patient  should  have full access to all of the information typically displayed on the interrogation reports.What Medtronic seems to offer to the smart app holder is the battery voltage reading and the expected battery lifetime and the daily activity.   You will need to use your app to send in the interrogation to the Medtronic mother ship from which your physician or the third partly interrogation report reader company can access the report.

So  now it seems that  gathering the data from your Pace Maker and transmitting  it to Medtronic falls upon the patient and his internet connection and his modem/router. while previously all of that was done by the hardware and software supplied by the pace maker company. You did not need an internet  connection or even a phone line which in the past was a means of sending in data to the company/

My thinking is that the current bed side system works well and I see no reason for me to take on the responsibility of the care and feeding of the electronic mechanisms and hardware to transmit the interrogation.When and if the bed side unit fails or wears out Medtronc will send you another without charge.When your smart phone dies you will replace it .

In 2013 the Heart Rhythm Society published a position  paper on the issue of remote interrogations (RI) and remote monitoring  (RM) of CIEDs ( cardiac implantable electronic devices).  As pointed out in the HRS paper, RI and RM are often used interchangeably with RM being used " colloquially for both" 


Libertarian takes on covid vaccination mandates and anti mandate mandates

 Robert A Levy of the Cato Institute discusses some aspects of the recently announced covid 19 mandates on the Septembers 1 Bob Harden Show podcast. 

Interestingly  Levy did not specifically use the term which is   the so called prime directive of libertarianism. The non aggression axiom. If one believes that the world is in the throes  of a pandemic involving a respiratory virus that spreads by aerosol transmission and that this  disease is very contagious and that vaccinated and of course unvaccinated can spread the disease and that masks mitigate the risk and that vaccination mitigate the risk then not wearing a mask in public in an area in which the disease is spreading should be considered an aggressive act.Therefore not wearing a mask under those conditions is about as un libertarian a thing as there be.  

 Governors Abbott and DeSantis have through their executive actions and/or legislation they sponsored acted to limit the private property rights of business owners in their states. Business owners have the right to set the terms and conditions of their employees and the terms of business arrangements of their customers. Both governors have prohibited  businesses from utilizing a de facto vaccine mandate regarding their customers. Conservatives have long favored a " no shirt,no shoes no service" business approach. which they now discard in an effort to what they seemingly believe to   gain approval of  a minority of Republicans who are perceived to be strongly anti  mask and anti covid vaccination under the faux banner of preserving freedom while actually abrogating the property rights of business owners. 

Saturday, January 28, 2023

My "journey " with a pacemaker and His Bundle Pacing

 In October  2015 I was implanted with a pace maker which used a His Bundle (HB) lead.Every thing it seems now is thought of or written about as a journey so I tell my journey.

Since I developed a high grade second degree heart bock that was precipitated by exercise and a left bundle branch block (LBBB) also,I was a candidate for a pacemaker (PM) and cardiac resynchronization therapy  (CRT) which at the time was synonymous with bi-ventricular pacing (BI-V) .

BiV has been  accomplished by atrial pacing,right ventricular pacing and left ventricular pacing which was done by inserting a pacing lead into a vein of the epicardial surface of the left ventricule (LV) .which was accessed by placing a catheter into the coronary sinus in the right atrium and threading it into a LV epicardial vein.

My EP cardiologist had a different approach. He implanted a lead in the right atrium and placed the ventricular lead near the bundle of  His in the interventricular septumThe third  lead was placed in  a vein on the surface on the left ventricle.This bi-V approach  is done in cases of heart failure (HF) in which there is significant desynchrony of the left ventricle (LV) which reduces cardiac output and leading to significant deleterious cardiac remodeling. 

The LV lead was to be a back up lead and  in the first five years was not needed as during implantation the Right ventricular catheter recorded a His Bundle signal  which captured the Purkinje System and provided a narrow QRS complex replacing the LBBB. The HB pacing was considered to be "non-select" HB pacing as both the His Bundle and a portion of myocardium was stimulated giving an EKG with a delta wave resembling the EKG of an anteroseptal preexcitation pattern.

Non select HBP is thought to be as effective as select HBP ( in which there is only capture of the His Bundle and the EKG has an isoelectric  interval between the stimulus and ventricular capture signal) in terms of cardiac output.

HBP typically has requested a higher capture voltage than does right ventricular apical capture and has a greater incidence of need for lead replacement and may have a lower r wave. HBP has also required a longer implantation time and higher incidence of  failure to capture rate. All of those issues have become much less of an issue as operator experience has increased and better catheters have become available with procedure times being shortened, capture threshold lower, and fewer cases of that require a  lead replacement. 

The post implantation period was not without drama. The first night the chest pain was severe and frightening and I felt lightheaded. I had been NPO from midnight of the day preceding the procedure day  and although the procedure was scheduled for 7 am , because of an intervening emergency it was after one pm before I went into the cath lab by which time I was likely moderately volume depleted. 

This lead to a situation in which I had chest  pain and a low blood pressure.My wife also a physician were able to convince, badger and intimidate the rookie nurse to run in more fluid.The fluid and a shot of morphine  relieved the pain and volume depletion  correction alleviated the weakness. 

 3 days later I developed left sided pleuritic chest pain,a heart rate of 150 (shown to be atrial flutter on EKG) and an emergency Pulmonary CT angio was interpreted as showing several pulmonary emboli in the left lung and a peripheral pulmonary infiltrate in the same area. 

 Symptomatic Pulmonary emboli after pacemaker implantation are uncommon.One  study using  V/Q lung scans demonstrated probable emboli in 15% of a small number of asymptomatic casesI had a repeat pulmonary CT scan following 3 months of apixaban which was normal .

Six years later my pacemaker battery was nearly end of service and I had a pacemaker replacement. No post op complications occurred this time.


 In 2006 ,Rafael Barba-Pichardo et al  from Spain published a series of cases of HBP which included a single case of using the His Bundle to pace a patient with heart failure in whom a LV vein could be assessed. This appears to be first case report of HB paced CRT/

In 2010  DL Lustgarten et al accomplished direct His pacing in 10 patients who were candidates for Biv pacing.  ( Lustgarten Dl Electrical resynchronization induced by direct his bundle pacing ..Heart Rhythm 7 , 2010 p 15 

In 2017 Rodney Tung from Chicago and Kalyanam Shivkumar from UCLAA (2) reported a series of 21 patients in a study the purpose of which to assess the feasibility of a His-bundle lead for CRT in place of the coronary sinus lead.

1)Barba-Pichardo, R et al , Permanent His Bundle Pacing in patients with infra-Hisian atrioventricular block. Revista Espanola de cardiologia, vol 59m553-558

2)Ajijola,OA et al Permanent HIs-Bundle pacing for cardiac resynchronization :initial feasibility study in lieu of left ventricular lead.Heart Rhythm2017,sept 14 (9) 1353-1361

Thursday, January 19, 2023

Exercise level ,cardiovascular risk reduction and risk of atrial fibrillation

 Six years ago  after I had recovered from my pacemaker implantation and the subsequent complications  (pulmonary emboli and pocket hematoma)  I mentioned to my EP cardiologist that I believed that I could run a half marathon. I had abandoned thoughts of completing a full marathon  because for  the proceeding two years I had barely finished in under six hour which was the cut off time to be officially counted as a finisher. for the full marathon.

The EP doc said that is not a good idea and when asked why he mentioned the risk of atrial fibrillation. I thought he was wrong but let the mater drop. I did not doubt that there is a relationship between running and AF but felt sure that the level of exercise sufficient to train for a half marathon was not in the range where there would be worry about AF.

The irony of recently seeing the EP doc's picture posted by him on a social medium site showing him with the half marathon medal along with his finishing time  did not go unnoticed. 

This is a good time to review the current recommendation for exercise to reduce cardiovascular risk,at what level of exercise  does it becomes too much or a good thing,and at what level does there appear to be an increased risk of atrial fibrillation. 

Currently the widely accepted view  and the WHO recommendation is that as a minimum one should exercise at a  level of 8 met hours per week.This is equivalent to 1/2 hr of moderate exercise for five days a week. Moderate is defined at a 3-6 Met level.8 met hours per week can also be achieved by vigorous exercise ( defined at greater then 7 mets) for 1.25 hours per day for five days  per week.

8 met hours per week is good but it is widely believed that at least a bit more is better, for example exercise at twice the minimum level would be better in term of cardiovascular risk reduction.This would be exercising at a moderate intensity for one hour a day for five days a week. 

So it seems in terms of cardiovascular risk reduction more is better but there must be limits to that.Is there a level of exercise beyond which there is no further improvement in risk reduction?

Eisvogel's data analysis suggest that that level is around 41 met hours per week. That is five times the minimum or 2.5 hours of moderate exercise per day five times a week . Interestingly the risk reduction exercise volume curve flattens out at a much lower level for vigorous  exercise, at 11 Met hrs per week according to Eisjvogels analysis data from Wen and from Aren.    

At what level of exercise can we expect an increased risk of atrial fibrillation?

Data from Ricci 2018 suggests that level may be about 55 met hours per week or 7 times the minimum recommended dose which would be 3.5 hr moderate exercise per day five times a week 

The level of exercise sufficient to train for a half marathon is definitely less than the estimated threshold for increased risk of atrial fibrillation. Check out any of the numerous half marathon training program and you will see the volume suggested is much less than 7 times the minimal WHO recommended exercise level.


Wednesday, January 18, 2023

Automatic threshold capture proven to work well for apical pacing but not for His pacing

 The thresholds for capture of the ventricular muscle may change over time with changes in the myocardial excitability which may be related to disease progression , electrolyte variation ,exercise,temperaturre etc. 

With the development and proven effectiveness and safety of automatic threshold determinations pacemakers were able to have longer battery lives and  there was more assurance of ventricular capture than was possible with in office threshold determination every 3 or six months as was the practice.  Automatic capture management (ACM) s have clearly been a useful development in PM technology.Patients' threshold levels could be measured daily. 

Various pacemaker manufacturers have developed their own automatic capture management systems and have become commonplace..

However since the increasing use of conduction system pacing in the form of His Bundle pacing,problems have become evident with  ACM algorithms.

Journal articles by Haran Burri and P. Vijayaraman have described the problems with HBP and ACMs. In regards to ACM issue details vary with what port on the PM is the His lead attached and whether there is selective or non-selective His pacing.

The story of left bundle branch block from interesting anomaly to a electrophysiologic fixable condition

In the beginning the EKG pattern of LBBB was an interesting phenomenon . William Einthoven in 1925 presented a case with a tracing that had also been recorded 31 earlier in the same patient. No one knew what the tracing signified and Dr. Einthoven remarked that the patient with this finding seemed to not be bothered by any heart symptoms.

As time went on it was realized that the pattern represented a "block" or conduction delay in the left branch of the Bundle of His and became established as a reliable sign of heart disease, it being often associated with ischemic heart disease,hypertensive heart disease and various cardiomyopathies.

Occasionally LBBB was noted in patients without obvious structural heart disease and the effect(s) of the cases of "lone "LBBB  on cardiac function was not initially appreciated.

 However, as early as  1979  physiologic studies  (1) on "lone LBBB" demonstrated significant septal and left ventricular  wall motion abnormalites associated with decreased left ventricular function and impaired relaxation. Later numerous studies on LBBB have detailed  the pathophysiology of the electrical and mechanical dyssynchrony of LBBB as well as molecular perturbations and deleterious ventricular remodeling.

In 2005 and 2013 reports from France described a cardiomyopathy that occurred with variable latency periods from the onset of LBBB that was to varying degrees reversible by cardiac resynchronization therapy (CRT) . Think about that for minute. LBBB may cause a cardiomyopathy that is possibly reversible by CRT.

Recognition of the role of a prolonged QRS and decreased cardiac function and the role of ventricular dyssynchrony in HF lead to idea of cardiac resynchronization therapy (CRT) in which there was pacing of  both the right ventricle and the left ventricle( with a pacing lead in  a coronary vein accessed via the coronary sinus)  in an effort to restore synchrony between the septum and the ventricular free wall.

From 2001 through 2009 there were several randomized clinical trials that demonstrated the efficacy of CRT in improving cardiac function, lessening  symptoms and in reducing mortality in heart failure patients.

As CRT was increasingly used to treat refractory heart failure (HR) it was realized that patients with a LBBB pattern were more likely to respond favorably and that CRT was essentially a treatment for LBBB.

Risum has published data from speckle tracking echo studies that suggest that the LBBB patients with HF who  respond favorably to CRT are those with a particular contraction pattern consisting of early septal activation and bulging of the lateral left ventricle followed by contracting of the LV with peak contraction occurring after aortic valve closure.

Sunday, January 15, 2023

Will morphing physicians into health care providers destroy their placebo-witch doctor power

Thoughts catalyzed by lecture by Dr. Olshansky on the placebo effect  at Methodist Cardiology Rounds.

In out ancestral, tribal- based behavior maybe there is some DNA driving us to seek out and follow leaders, strong wise individuals who can shepherd us through tough times- societal and even personal as in health care matters.

Knowing as much as I know about doctors and medicine and clinical trials and  fragile and contradictory  guidelines  and the utter impossibility of being able to keep up with every thing even in  your own  subspeciality  and the temporal fragility of medical advice I think I have largely lost the capability to benefit from the placebo- witch doctor -effect when -I absolutely have to see a doctor HCP.

The question I am raising here is will HCPs without MD degrees pack the same placebo power as physicians for those who are not as skeptical as I am of the physician's ability.

Does what goes on behind the anesthesiologist drapes stay behind the drapes?

 At least some of what occurs behind the anesthesiologist drapes stays there not  being completely captured by the surgeons op note.  This is the case because the surgeon does not know what goes on in real time focused as he should be on the details of the procedure.

The story

I have a pacemaker, a dual chamber  in DDD mode with the right ventricular lead placed in close proximity to the Bundle of His.Typically this is referred to as non select His Bundle pacing, I was to have surgical procedure with the operative field to be within a few centimeters of the pacemaker .

It is common practice to deactivate the sensing function of the PM since the cautery typically used in surgery can emit electromagnetic energy  ( electromagnetic interference (EMI )) that can damage the PM or change its function with variable clinical consequences.

The sensing function of the PM can be disabled by the application of a magnet over the PM.This converts a  PM in DDD mode to one in D00 mode in which the atrium and ventricle are paced typically at a rate of 85. This is called asynchronous pacing and referred to as magnet mode .

This eliminates the risk of EMI but at the cost of limiting the heart ability to increase cardiac output and poses the risk of ventricular tachycardia or ventricular fibrillation if a pacing spike should occur at the vulnerable phase of repolarization. If the patient has a functioning sinus node and  intact electrical transmission  there will be two competing rhythms .  

The operative record include a series of Blood pressure recordings all of which in my case were normal.Yet the medication record includes levophed which would have only been used if the blood pressure has decreased significantly. So that fact must have stayed behind the drapes.

Could the presumed blood pressure drop be due to the magnet mode not allowing an intrinsic increase in cardiac output assuming there was a valid reason for the use of levophed?


Thursday, January 12, 2023

Can we define the level of high volume endurance exercise above which mortality risk increases?

Can the level   of high volume endurance exercise above which mortality risk increases be defined.

An important study with data from the Cooper Clinic in Dallas provides some information on that question.

Defina  et al (1) presented data from a large cohort of men ( 21,758) with ten years of more of followup. In the group there were 432 men with  an  exercise history of equal to or greater than 3000 met-min per week .This is approximately equivalent to one hour of vigorous activity per day ( at a level greater than 7 Mets  which is the oxygen uptake required to finish Stage 2 on the Bruce protocol).This is a level of exercise about 6 times the minimal level of vigorous  ( greater than 7 Mets) exercise per week recommended by the 2018 guidelines.

Men in this group had a greater risk of having a coronary calcium score of 100 or greater but their risk for cardiovascular mortality (CVD) and all cause mortality was not greater than men exercising at lower levels and was lower than the least active men  in that cohort. This was the case even though they had higher CAC scores which generally predicts a higher cardiovascular risk.

Franklin and co-authors (2) said this about the DeFina study:

" These finding refute the notion that high-volume endurance activity ( greater than one hour/day) increases mortality regardless of CAC level"

The issue in the De Fina article  was the signficance of increased CAC in long time endurance exercisers on cardiovascular mortality but it also  provides some information regarding the title question .

1)DeFina,LF et al Association of all-cause and cardiovascular mortality with high levels of physical activity and concurrent artery calcification. JAMA Cardiology 2019 42 (2) 174

2)Franklin, BA Exercise related acute cardiovascular events and potentially deleterious adaptations
following long term exercise training. Placing the risks into perspective-An update A scientific statement from the American Heart Association. Circ 2020 Feb 26 PMID 32100573