Posted in Cardiology - Animations, Cardiology -Emerging technology, Cardiology -Interventional -PCI, cath lab tips and tricks, Left main stenting -Tips and tricks, Uncategorized, tagged aorto ostial left amin stenting, aorto ostial lesions, buttoned stent for left main ostium, how to do left main stenting, left main ostial stenting, left main stenting, new techniques for left main stenting, ostial left main lesion, ostial lesion, stent design for ostial lesions, tips and tricks in coronary stenting, tips for left main stenting on February 8, 2014| Leave a Comment »
Left main ostial lesion remains a challenging task .A new stent design is proposed here.
The lesion
The hardware
The technique
Final message
This thought came when I recently encountered a patient with a left main ostial stent which was projecting well into aortic root .It is an open access patency ,whoever is capable of converting this idea to a clinically applicable technique is welcome to proceed !
Posted in Uncategorized, tagged dr s venkatesan wordpress blog on January 1, 2014| Leave a Comment »
The WordPress.com prepared a official 2013 annual report for this blog.
Here’s an excerpt:
The Louvre Museum has 8.5 million visitors per year. This blog was viewed about 540,000 times in 2013. If it were an exhibit at the Louvre Museum, it would take about 23 days for that many people to see it.
Click here to see the complete report.
Posted in Cardiology - Electrophysiology -Pacemaker, tagged asynchronous mode, magnet rate, pacemaker issue, problem of over sensing, use of magnet in pacemaker evaluation, vvi pacemker on November 16, 2013| Leave a Comment »
Every pacemaker has a metallic “Reed switch” . Putting this switch on and off is possible with an external magnet .The circuitry is such that , switching on makes sensing function null and void.It functions as asynchronous mode.In other words pacemaker converts to a mandatory pacing mode .All sensing related issues are immediately removed.
Note : This switch can be activated by any strong magnetic filed applied externally .And removing the magnet disconnects the circuit.
When a magnet is applied the pacemakers changes the mode in the following way.
Purpose of magnet application .
Essentially it may be called as a safety mechanism to prevent external sensing in strong electrical fields in case the need arises.
Indirectly , it may aid us in detecting end of life of battery as well
During elctrocautery and related procedures application of magnet will help.
What is magnet rate* ?
* Always check with the pacemaker manual for the exact response.
When I put a magnet over nothing happened .What is the inference ?
What happens during magnet application in ICD ?
Is there any risk of applying magnet ?
Since magnet removes the sensing function , interfering a cardiac rhythm which is dependent on sensing can be problematic.Similar situation arises in MRI scans and other magnetic fields.
Hence , application of magnet in a patient as a part of pacemaker trouble shooting who has no pacing spikes is rarely a problem While one should not do it without supervision of a learned cardiologist.
What is smart magnet ?
Each pacemaker and ICD is interrogated with the respective programmer.As such , there is no cross brand programmer available.This makes it difficult for patient( as well as physicians) to call for help in case of malfunction.
The solution is to make standard universal analyser and programmer .This requires cooperation between various stake holders.Meanwhile as temporary relief a magnet which can community two way with basic functional switches can be developed .
There is a need for universal smart magnet with constant interaction between device and magnet ..
Since , the generation next generation human heart is going to be wired and deviced in a complex manner, we need to know the basics about these issues.
Final message
Magnet application is akin to novice’s pacemaker analyzer. Every cardiac care unit must have one in their shelf. It aids us to diagnose over-sensing as a cause for pacemaker malfunction.(* please note , it has little role in all other pacemaker issues !) .In an emergency it can help stop inappropriate ICD shocks.(More importatnly It gives time to call an expert ! )
Reference
Posted in Cardiology - Electrophysiology -Pacemaker, cardiology -ECG, Cardiology -unresolved questions, Infrequently asked questions in cardiology (iFAQs), Permanent pacemaker, tagged lbbb and rbbb during pacing, mechansim of rbbb in rv pacing, RBBB during pacing, right bundle branch block during pacing, safe rbbb pacing, septal rvot pacing and rbbb in ecg on October 29, 2013| Leave a Comment »
We expect LBBB in RV pacing . . .but if RBBB is recorded we are worried ! (Often times it may be neither LBBB nor RBBB )
Is it really a panic situation ?
What should we do if we encounter RBBB morphology after PPM ?
If everything is fine , just forget the RBBB.Don’t split your hair for this apparent paradox. In medicine impossibilities will always galore !
This paper from Taiwan would vouch for this
Posted in Cardiology - Electrophysiology -Pacemaker, Cardiology -Interesting videos, Cardiology -Pacemakers and ICD, tagged ICD, implantable cardiovertor defibrillator, Indications for ICD, live icd shock on October 25, 2013| Leave a Comment »
This post , is probably not meant for cardiology professionals.
Few technologies are clear winners in modern medicine. ICDs play games that would rival the God !
What is an ICD ?
Here is a man , who drops almost dead by a fatal cardiac arrhythmia . In few seconds ICD machine recognises this arrhythmia ,charges itself and fires a shock of about 30 joules direct current .The arrhythmia is reverted and the fellow gets up as if nothing has happened !
Watch this video
This revolutionary devices are to be used judiciously in individuals with high risk for dangerous cardiac arrhythmia.
The current indications as on 2012
Reference
Posted in Cardiac biomarkers, Cardiology - Electrophysiology -Pacemaker, cardiology -ECG, Infrequently asked questions in cardiology (iFAQs), NSTEMI, tagged cpk mb in nstemi, definition of nstemi, nstemi, troponin positive unstable angina, unstable angina on October 22, 2013| Leave a Comment »
This question always creeps in any coronary care unit.
Posted in Cardiology - Electrophysiology -Pacemaker, Cardiology -Emerging technology, cardiology innovation, Cardiology Innovations, cardiology journal club, Cardiology-Land mark studies, Future cardiology gadgets, tagged changing batteries in vvi pacemaker, future of permanent pacemaker, implntable rv vvi pacemaker, st jude naostim wirelss pacemaker, wireless pacemaker on October 18, 2013| Leave a Comment »
Few Innovations are real breakthroughs in cardiology . Here is an imminent technology waiting to explode in the permanent pacing . Expected to hit market next year (2014 in Europe ) FDA approves clinical studies .
Click over for the animation video of the procedure .
Future directions in Permanent pacing.
The only threat for this technology is the concept of biological pacemaker Converting ordinary myocytes into pacing cells by genetic engineering.This is expected to happen within few decades.
Posted in Atrial fibrillation, Cardiology - Electrophysiology -Pacemaker, rheumatic heart disease, tagged maangement of af, maze corridor surgery in af and rhd, ptmc plus rf ablation of atria, pulmonary vien isolation rheumatic af is useless, rf ablation in rhd, RF ablation in rheumatic mitral stenosis, surgical la ablaton for atria fibrillation, therapeutics in atrial fibrillation on September 30, 2013| Leave a Comment »
No procedure is impossible in medicine . . . but it should be useful for the patient !
//
Posted in Cardiology - Electrophysiology -Pacemaker, Cardiology Innovations, Pace maker Tips and tricks, tagged advantage of tine over screwing lead, anchoring a lead in rv apex, combined tine and screw leads, inter trabecualr screwing, pacemaker lead, rv apex and sea bed, rv pacing lead acute dislodgement, tine vs screw, tips and tricks in pacemaker lead, trabecular screwing of pace amker lead on September 30, 2013| 2 Comments »
Pacemaker lead implantation is basically a blind procedure .We are supposed to pace the RV apex . It is akin to anchor a ship in the sea bed. Screwing leads are preferred in permanent pacing ,but tined leads have few unique advantages as well .
Can we combine the advantage of both ?
It is believed displacements are more common with tined leads . May be yes . . . or is it really so ?
It is not the tines or screws that is going to determine the early displacement , rather , it is the expertise , commitment and the time spent during the implantation that matters . I have witnessed equal number of early lead dislodgement in both .
One issue often goes unreported is that , when screwing lead is used operator is subconsciously complacent.While cardiologists who implant tined lead is more cautious , make sure it is well trapped in RV.
Screwing leads.
Tined leads
What does experienced cardiologists say ?
Cardiologists before the era of EPs were using only tined leads without any major hitch . I know electrophysiologists rarely use tined leads now . In our institute , with a cumulative experience of over 3000 pacemakers over 30 years( 99% are with tined leads ) , we have no reason to believe they are vastly superior technique.
However there are few definite Indication for screwing lead
* Note all atrial based pacing are screw based as atria lack trabeculae.
A suggestion
Final message
I would believe ,there is no major difference in both short and long term outcome between these two system of leads.Each has it’s own advantage.
After thought
Why can’t we accrue the benefits of both ? I think we have good scientific reason to request the pacemaker industry to design a lead which can have both tines and screws to provide double safety .Simple isn’t ?
Posted in Cardiology - Electrophysiology -Pacemaker, cardiology -Therapeutics, Cardiology -unresolved questions, Syncope, tagged cardiac syncope, mechanism of syncope in chb, mechansim of stokes admas syndrome, sick sinus syndrome, sinus node dysfunction, stokes adams morgagni, stokes adams syndrome, stokes admas attack on September 30, 2013| Leave a Comment »
Syncope in CHB is due to unsafe escape rhythm, changing focus of VPDs, extreme bradycardia, (<20 /minute), pause induced VT, (Usually polymorphic and torsades is quite common .) ultimately may end with convulsions, ventricular fibrillation, and death.
Syncope in SND is due to extreme slowing of SA node . Sinus pauses or even arrest can happen resulting in ventricular standstill. Fortunately, a stable escape rhythm ensues more often than in CHB. (It may just be around 20 or 30/mt. still, ventricular arrhythmias are uncommon. ) This implies an important fact that stability is more important than slowness.Fatality is rare in SND.However, the mechanism of syncope in SND is influenced by the integrity of AV conduction also. If it is severely impaired it can trigger ventricular arrhythmias as well as the escape focus becomes unstable infra hisian location.
Paradoxically, in patients with SND, an episode of palpitation due to AF or sinus tachycardia precedes the episode of syncope. An intelligent patient may recognize this as a warning and can take lying posture after runs of palpitation.This is because of tachycardia-induced suppression of SA node prolong the sinus node recovery time still further.
How to differentiate cardiac syncope from simple vasovagal syncope?
Cardiac syncope is differentiated by common vaso-vagal syncope (VVS) as the latter occurs during erect posture . It may be entirely due to vascular component and hence it may simply represent hypotension without a true cardiac limb .(Vasodepressor syncope)
Hence the pulse rate and volume may take some time to recover in VVS, while Stokes Admas of CHB usually have a well-formed bounding pulse in the recovery phase, as the rate is low and systemic hypoxia is a consistent feature.
How is the respiration during Stokes – Adams syndrome ?
Intact. Oxygenation in the lungs goes on for time being. The pooled pulmonary blood gushes after the termination of syncope and causes the classical flushing. Since the hypoxia causes systemic vasodilatation the flushing is more obvious.(Unlike vasovagal syncope where they are often pale)
History of stokes Adam’s syndrome Morgagni is the one who gave credit to their discovery
Though Morgagni first described the clinical picture of this syndrome in 1761, It was published much later by Two Irish Physicians Stokes, Adams. Wish this entity is referred to as Morgagni-Stokes-Adam’s syndrome
Reference
2.W. Stokes. Observations on some cases of permanently slow pulse. Dublin Quarterly Journal of Medical Science, 1846, 2: 73–85
Dr.S.Venkatesan MD 