I was stunned to read this article regarding the proliferation of open access , author paid scientific literature from “The Hindu ” dated 27th September 2012 .
It only shows how the scientific world is being consumed by commercial interests .
It seems at every level of journal creating and publishing there is vested interest .
I wonder peer reviewed journals could mean nothing in the near feature .
Let us join the new movement called “Paid science”
Posted in bio ethics, medical quotes, Venkat quotes | Tagged ethics in medicine, fraud in science, paid science and open access article | Leave a Comment »
What are the factors other than EF % that determine functional capacity in cardiac failure ?
In our experience we have found the following factors contribute immensely to the functional capacity of cardiac failure patients
* May have major Impact on functional capacity
Final message
Physicians and even cardiologists are obsessed with EF % to a large extent . My guess is , it is not likely to end in the near future . The irony is , we have passed it to our colleagues (Like anesthetists !) and patients as well .( for various reasons )
Please remember , there are at-least 10 factors that are important in the genesis of symptoms of heart failure . The list can extend further if we include like associated renal dysfunction , hemoglobin concentration , etc .
Even though LV pump primarily determines the ultimate outcome in cardiac failure , it is unwise to blame the EF % for all the suffering . If only we realise this fact , one can take appropriate measures .
** Paradoxically modalities aimed to improve LVEF by positive inotropics has never been shown to improve the outcome .In-fact , there is more evidence for the contrary !
Posted in cardiac failure, Cardiology - Clinical, cardiology -Therapeutics | Tagged cardaic failure symptoms, ef%, ejection fraction, limitations of ejection fraction, skeletal muscle function in cardaic failure | Leave a Comment »
Ironically , in medicine we need to peep into the past for updating and scrutinizing current knowledge . Here is free ticket for a retro journey to the the Electro-physiology Laboratory of the University of Wisconsin-Milwaukee . This article , which was published in 1990 , still can explain many intriguing concepts of VT succinctly .
Thanks to circulation for sharing this article free !
Akhtar M . Clinical spectrum of ventricular tachycardia. Circulation 1990;82:1561-73.
Posted in Cardiology - Electrophysiology -Pacemaker, Cardiology-Arrhythmias, Uncategorized | Tagged best review article in ventricular tacycardia, maasood akthar and ventricular tachycardia, mechanisms of ventricular tachycardia, ventricular tachycardia | Leave a Comment »
That’s how one of the patient presented to our hospital . An echo documented severe aortic stenosis with a peak aortic gradient of 80mmhg and a bounding systolic blood pressure of 180 mmhg . Is that an exception ?
I recall the early days of medical school when we are fervently taught that systolic blood pressure is primarily determined by stroke volume and LV contractility .
The above example clearly proves this is explicitly wrong .
Now , we understand systolic blood pressure have many determinants . Stroke volume is just one of them .
The tone , distensibility of major blood vessels arising from aorta determine how a pressure wave is going to get amplified .
If you say stroke volume is not major determinate of systolic blood pressure . . . . does it imply , the antique bed side cardiac sign Pulsus parvus et- tardus a myth ?
No , it still holds good . But it is not a hard sign . We realise now , a patient with a well felt carotid can have a severe Aortic stenosis .
What will be the central aortic pressure in critical Aortic stenosis ?
It is definitely lower than brachial cuff pressure .This will explain the systolic blood pressure is actually an amplified signal .
Posted in Cardiology -unresolved questions, Clinical cardiology, Infrequently asked questions in cardiology (iFAQs) | Tagged aortic stenosis, effect of ar on systolic blood pressure on aortic stenosis, pulse volume and stroke volume, pulsus parvus et tardus, ssytolic decapitation of blood pressure, stroke volume and systolic blood pressure | 4 Comments »
Rescue PCI rescues
Answer:
All of the above can be a correct response in varying situations.
Posted in Cardiology -Interventional -PCI, cardiology -Therapeutics, Cardiology -unresolved questions, cardiology- coronary care, Cardiology-Coronary artery disese | Tagged defintion of rescue pci, rescue pci, rescue vs primary pci | Leave a Comment »
Which is the most important factor that determines thrombolysis failure in STEMI ?
Answer : 3 .(Though all 5 factors operate )
Failed thrmbolysis occur in about 40-50% after streptokinase and slightly less with TPA and TNK-TPA . Delayed arrival and late thrombolysis are most common cause of failed thrombolysis. As the time flies , the myocardium gets damaged and the intra coronary thrombus gets organised .Both these processes make delayed thrombolysis a futile exercise.
Not all STEMI patients have large thrombus burden. There need to be a critical load of thrombus for thrombolytic to be effective
Some may have a major mechanical lesion in the form of plaque fissure, prolapse and it simply blocks the coronary artery mechanically like a boulder on the road . The poor streptokinse or the rich Tenekteplace ! nothing can move this boulder .The only option here is emergency PCI .
It is impossible to know.That’s why primary PCI has a huge advantage. But still thrombolysis is useful as some amount of thrombus will be there in all patients with STEMI.Lysing this will provide at least a trickle of blood flow that will jeep the myocardium viable and enable us to take for early PCI.
The commonest cause for thrombolytic failure is the time of administration and the degree of underlying mechanical lesion . So it does not make sense to blame streptokinase always !
Posted in Cardiology - Clinical, cardiology -Therapeutics, cardiology- coronary care | Tagged failed thrombolysis, streptokinase, tnk tpa, tpa | Leave a Comment »
Answer : 2 Most shunting occur by direct streaming of RV blood into Aorta . If the aortic override is near 50 % it need not even cross the VSD in it’s circuit. (Although theoretically all of the above can occur)
Posted in Cardiology -unresolved questions, cardiology congenital heart disese, Infrequently asked questions in cardiology (iFAQs) | Tagged left to right shunt in tof, right to left shunt in tof, tetrology of fallot | 2 Comments »
The last rites for routine Swan Ganz catheterisation ( In STEMI ) was performed by a land mark JAMA article in 1996 .
Now . . . is the turn for intra aortic balloon counter pulsation (IABP) .
A conceptually attractive concept was laid to rest in Munich ,West Germany , this week at annual European society of cardiology , Scientific Sessions .August 2012 .
What a crash for a great hemo-dynamic principle in acute MI which ruled the roost for over three decades !
Just Imagine , how many man hours , millions of worth of consumables wasted . . . better not to talk about associated aortic injuries .
This is what we call “premature evidence based harm”
I wonder . . . whether I am justified in making this extreme comment .
Please read for yourself , this early online release alert from NEJM .
http://www.nejm.org/doi/pdf/10.1056/NEJMoa1208410
Reference
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2352214/pdf/bmj00561-0005.pdf
Posted in Cardiology -Interventional -PCI, cardiology -Therapeutics, cardiology- coronary care, Cardiology-Coronary artery disese | Tagged esc munich 2012, iabp for cardiogenic shock, iabp shock 2, primary pci and iabp, unlearning cardiology | Leave a Comment »
The principles of pre-discharge EST
This concept came about 20 years ago (1980s) to risk stratify patients following ACS to triage early coronary angiogram and revascualrisation. Generally patients are discharged by 5-7 days after an MI (May be 3-5 days in some hospitals) . Doing an exercise stress test early within 2 weeks has not been very popular with many cardiologist even though it was recommended by many guidelines.The type of stress recommended here , is heart rate limited sub maximal 70% of THR (Usually around 140 /mt ) is performed . This is due fear of precipitation another ACS.
Still, there are definite advantages for pre-discharge EST .It help us identify high risk subsets of STEMI and reduce the intermediate term mortality .More importantly it gives us an opportunity to exclude inappropriate revascualriations even without an angiogram . (The well known coronary dogma ie if a post STEMI patient performs > 10 METS , his heart carries little risk for future events still holds good !)
With the advent of liberal usage of CAG and improved techniques of revascularistion , most patients directly undergo pre-discharge CAG rather than EST !
Further reading
Does any cardiologist have guts to do a pre- discharge EST after a successful primary PCI ?
Posted in cardiology-ethics, Cardiology-Land mark studies, cardiomyopathy, Echo library and gallery, Great websites in cardiology, Uncategorized | Tagged pre discharge est, pre-discharge tmt est tredmill, primary pci est, status of pre discharge est, stress test following primary pci, sub maximal stress test | Leave a Comment »
An awkward argument for routine EST following primary PCI
Please remember, primary PCI is not the end of the management of STEMI. Primary PCI is an IRA focused intervention. We need to study other lesions and their the flow pattern as well. Logically we need to do a test for adequacy of baseline vascularity and the current revascularisation . Simple deployment of a stent in IRA (without documentation of good flow during exertion ) is not acceptable to believers of scientific medicine . Resting TIMI 3 flow conveys no meaning for a patient who is going to be ambulant and active. A stress test will come in handy .
The micro-vascular integrity and resistance following an extensive STEMI is best studied by the adequacy of exercise induced coronary hyperemia (This is physiologically equivalent to the much fancied FFR in cath lab ) . One can consider EST following a primary PCI as an non invasive substitute for the collective FFR of all three vessels including the IRA that is stented .
Does any cardiologist have guts to do a pre- discharge EST after a successful primary PCI ?
Typical responses would be
If you think , it is too risky to exert a successfully revascularised patient early after a STEMI . . . at the same time argue to do it in non revascularised patient routinely . Do we not see a huge irony here ?
Other inference could be . . . we are still suspecting the quality of our revascularisation during PCI !
If EST is contraindicated after a primary PCI , are we going to advice these patients against indulging in any activity requiring moderate exertion fearing a stent occlusion ?
. . . What a way to interpret the aftermath of a ‘state of the art ‘ procedure called primary PCI !
In science , correctness is more important than politeness !
Posted in Cardiology -Interventional -PCI, cardiology -Therapeutics, cardiology innovation, Cardiology-Coronary artery disese, Infrequently asked questions in cardiology (iFAQs) | Tagged can we do excercise stress test following primary pci, pre discharge est after primary pci, pre discharge tmt | Leave a Comment »
Dr.S.Venkatesan MD 