Friday, July 15, 2011

This is Dr Kiran welcoming all to the new post of the blog.

This time, the delay in the posting was not my usual laziness, but it was because of some tight rope walking! It was arrival of my second baby. He was in a hurry and the delivery happened 18 days prior to the due date. We were obviously not well prepared and had to do some circus to get the things settled. Now that all iz well, I am posting this update on the blog. Hope I will get some comments this time, for right or wrong reasons!!

VOLUME Vs PRESSURE

I think we have discussed this issue earlier, but without much clarity. I wish someone replies this time. In cases of single ventricles with borderline high PA pressures, is the recommendation of PA tightening valid? One side of the logic is, by tightening the PA, flow into PAs would be lesser and thereby the pressure. Also, adding BD Glenn shunt in this situation would improve the saturation and off-load the ventricle.
On the other hand, tightening the PA would increase the afterload on the single ventricle and would nullify the effect of offloading the ventricle. Also, when the baseline PVR itself is less (baseline PA pressures in range of 18-20mmHg), what more improvement would PA tightening achieve in PVR/SVR ratio? When the long term threat is failure of single pump, is volume load better or pressure load?
Please let me know your takes on this issue.

THE NUMBER GAME

Sometimes, we decide to cath some borderline cases for objectiveness and end up cursing our decision to cath!! We had one-and-a-half year old with ASD and VSD with severe PAH, with saturation of 93%. His LV looked non-compacted and the extent of pulmonary hypertension was higher than expected for the extent of lesions. One of the consultants thought of acquiring more data on the issue and decided to cath. Data on cath showed a PVRI of 11wood units! Since the child had all the features of operability on clinical evaluation and baseline investigations, these numbers looked shocking. It is not easy to convince the surgical team to operate when the cath produces such results! However, one of the senior surgeons was kind enough to ignore the cath data and operated the baby! The learning was: when in doubt, don’t just cath. You may get unexpected turn in the way!! Please share your experiences in this issue.

END DIASTOLIC PRESSURES AND OPERABILITY

Many places follow the rule of diagnostic cath in Down syndrome babies with congenital heart defects older than 1 year. We had a 2-year-old baby with Down syndrome, who had a large inlet VSD. Although operability on clinical grounds was never an issue, it was sought by someone as ‘knee-jerk’ response. The LV EDP was documented to be 25mmHg. The tracings were verified and found correct. Barring that, the data on operability showed operability. One of the senior surgeons showed his reluctance in operating babies with high EDP. Our recommendation of leaving an ASD open also did not go well. What is the take of readership? Is high EDP a detriment in surgery? Can you recall having seen a similar situation and outcome of that baby? Please share your experiences and expertise in this.

DEVIL Vs DEEP BLUE SEA

As a matter of convention, I have heard many centers have different PVRI cutoffs for ASD and VSD operability. One convention was: less than or equal to 7 wood units for VSD/PDA and less than or equal to 10 wood units for ASD. The question was- when the PVRI is between 7 and 10 wood units in cases of VSD, can we convert the physiology into an ASD? In other words, can we close the VSD and create a sizable ASD in that patient? On long run, the progress of disease might be better with a pre-tricuspid shunt than a post-tricuspid one. However, our surgical team opined that giving another disease for one even after a major heart surgery is useless and worthless. Are there any studies on these lines? What would your personal opinion on this be? Please let me know. I would be interested if this issue can raise a debate.

RIMMING THE FLOW

In cases of toddlers with moderate to large ASD and near normal PA pressures, how frequently would one witness cyanosis? Even the sinus venosus defects of SVC type where the SVC straddles over both atriae, we rarely see cyanosis. I have seen 3 cases of sinus venosus defect of IVC type and not even one of those three had cyanosis. However, my experience in the latter is obviously less. It is said that a long, redundant Eusthecian valve can some times direct the IVC blood towards LA in low secundum ASDs with deficient IVC rim. In the absence of systemic venous anomalies and unroofed CS, is it possible to have cyanosis in ASD with normal PA pressures? We had one of such kids in our hospital. Conventional and saline contrast echo was not useful in deducing the picture. Cath study is unlikely to yield much. How would you go about in such cases? Please share your experiences on this.

That brings us to the end of the present post. Please send your criticisms and suggestions typed in the comments box or directly to my email: drkiranvs@gmail.com If you wish to contribute your experiences, please type them in a word document and send the attachment to my mail. I shall publish them on your behalf with full credit to the writer! See you shortly with few more learning scenarios.

Regards

Kiran

Thursday, June 16, 2011

Dr Kiran welcomes you to the new post of blog.

It is often told that thinking is easier than writing! However, I have found the contrary to be true. In the past 30 odd months of single focus blogging, I have found better expression with writing than verbalizing the same issue. All this is to tell the readership that writing comments is good – for yourself and for the blogger!!

Let us dwell into the interesting learning scenarios right away:

WHY COLLATERALS?

In post-Glenn status, it is not uncommon to find venovenous collaterals. How common is the development of new aorto-pulmonary collaterals during post-Glenn? We had an 11-year-old girl with such a picture. Her pressure data was normal and she also had good-sized branch Pas. However, she had leash of new aorto-pulmonary collaterals which was not found during the previous cath study. We know the impetus for venovenous collaterals – usually the dissipation of pressure. What is the impetus for new AP collaterals when the pulmonary arteries and saturations are OK? Is there any other impetus for development of new AP collaterals other than cyanosis? To best of what we have seen, this finding is infrequent. I would be interested in finding experiences and inputs from readers.

NEED OF HOMOGRAFT

This was a good learning. We had a 6-year-old with Tetralogy of Fallot with absent Right Pulmonary artery. On cath, we found the right lung supplied by three high pressure collaterals from thoracic aorta at T5-6 level. An innovative looking surgery was suggested by our senior consultant – resecting the collateral portion of aorta en masse, unifocalizing that segment with existing pulmonary artery and interposing a graft for the resected aortic segment. However, the surgical team was not keen on this, as the complexity of surgery would be higher for no better yield. It was decided that the lesion is overall repairable with unifocalization and intracardiac repair. The question was the need for homograft. It was successfully argued that the unifocalized high pressure collaterals would require competent valve. A transannular patch in such cases would result in torrential regurgitation due to high afterload. It was a good “retrograde” learning!

STABLE BLUE BOY

When we discuss the differentials of hemodynamically stable, asymptomatic blue toddlers, we often describe the utility of murmur. The general rule is, better the murmur – stabler the patient, as the bottomline in these cases are extent of pulmonic stenosis. For example, a toddler with tetralogy of Fallot with good murmur over left upper sternal border has better hemodynamic stability than the one without murmur. For, murmur indicates blood flow across the narrow RVOT. The exceptions to this rule are few. We had a toddler with uniform saturation of 76% in all limbs. He was totally asymptomatic- barring the only complaint: cyanosis. The arterial blood gases showed low pO2 and marginally high pCO2. His physical examination did not reveal any significant finding. Cyanosis and clubbing were confirmed. He had normal heart sounds and no murmur. Chest radiograph was normal. There was no reason to suspect cardiac cause of cyanosis. On echo, we found the issue. The SVC was opening totally into LA, without any ASD! There was no LSVC. IVC was normally into RA. All the pulmonary veins were opening into LA. Surprisingly, the LA and LV dimensions were normal. How these tougher chambers accommodated the extra blood without getting dilated was enigmatic! This was the first time I saw a partial anomalous systemic venous connection. I had earlier seen Raghib complex, but this one was new. The management is simple, but the presentation was puzzling and findings were not in mould! After a painful delineation of diagnosis, we found an outside report wherein they had not only diagnosed the problem, but had also done a saline contrast injection in the upper limb, documenting the entry of SVC flow into LA. Good show indeed! We searched the literature and found only 19 reported cases so far. Most of them had associated anomaly. This is probably one among very few cases of isolated RSVC to RA without any other cardiac anomaly.

BREEDING THE NEED

This is not the problem of one centre; virtually every centre I have come across have this problem – some more some less, but inevitably, yes. I am talking about the unnecessary diagnostic cath studies performed in our country. It is accepted that Pediatric cardiology is still young field and rigid consensus are not possible yet. But, many times, those children who have their decision written very well on clinical grounds end up getting diagnostic cath studies. Whether it is ignorance or felt-need or greed or breeding the culture of teaching the evidence to trainees is questionable. We do come across patients carrying reports and CDs wherein the cath study was done for absolutely useless indications. Consider these examples: 7-month-old child with failute to thrive, saturating 98% in room with large VSD. Another child with truncus arteriosus where one cannot get either the numerator or denominators of the equations to calculate cath data. Worse of the lot is when the consensus is made based on chest radiograph and ECG after a thorough cath study! Isn’t it possible to create an institutional consensus on the need for cath? Many centres do a combined cardiologist-surgeon cath meetings to discuss the decisions. Isn’t it time to do a pre-cath meet to decide the utility of cath study in individual cases? I strongly feel that everyone owes the responsibility of passing on scientific knowledge to those who look upon us. I have tried to bring up this issue many times, but the futility is obvious every time. I would like to hear experiences and thoughts of readers on this issue.

FATE OF THE UNPAIRED

I have brought up this issue once in the past, but this time it was bigger. We evaluated a 22-year-old DORV, VSD, PS who had undergone a BD Glenn shunt at an outside hospital in 2009 (at age of 20 years)! On enquiry, we understood that the earlier centre had planned a two-pump repair on her, but found the VSD to be non-routable. Hence, they took on table PA pressures and performed a Glenn shunt instead. However, she came back with no improvement in saturations or effort tolerance. Her baseline SO2 was 70%. We did the cath study in our centre. Her PA mean pressure was 12mmHg. However, we found a hugely dilated azygous vein entering the SVC. We balloon occluded the azygous to notice the increase in PA mean pressure to 14mmHg. Her IVC was not interrupted. Her EDP was 10mmHg. The question was: why did the azygous vein dilated so much? The lower body is well drained by the IVC. The PA pressures are acceptable. How did the azygous dilate at all? Normally, the azygous vein gets ligated during BD Glenn shunt. But here,http://www.blogger.com/img/blank.gif the previous centre had not done that. It is true that the azygous would behave like a pop-off, but can it dilate so much in the absence of any impetus? Is it only the pro-gravity phenomenon wherein the SVC blood finds it easier to drain into azygous than to PA? Are there venous valves in azygous? Please let me know your experiences on this.

That brings us to the end of present post. Please pen your criticisms and suggestions in the comments box or direct them to my email: drkiranvs@gmail.com See you shortly with few more learning scenarios.

Regards

Kiran

Tuesday, May 31, 2011

Dr Kiran welcomes you to the present post of blog.

As usual, I did not receive any comments for the last post. But I have heard that many people do read and follow the blog. Just that they are as lazy as I am when it comes to writing!

Without much ado, let us carry on with the interesting learning scenarios:

SMOOTH FLOW PALLIATION?

We had a 6-year-old with congenitally corrected transposition of great arteries, with small VSD (non-routable) and severe subvalvar and valvar PS. The LV was suprasystemic and TR was moderate. Neither double switch nor Senning-Rastelli were possible. The surgeons were not happy with the tricuspid valve and ruled that the conventional repair (RA to LV to PA and LA to RV to Ao) by pulmonary valve repair was inadequate unless the TV was also intervened. However, their scepticism was, “what if the TV is not repairable?” The child was too young for TV replacement. We argued that the pulmonic valve repair alone should bring down the LV pressures and improve the LV geometry. This would take away the Bernheim-reverse Bernheim effect and would improve the RV geometry in return, thereby reducing the TR. I felt this intervention would be better than leaving a suprasystemic chamber for follow up. But, this logic did not please the surgical team and they ruled out any such improvement. Although it sounds theoretical, I could see practical point in it. How would the readers like to decide? Please let me know the folly in this logic!

INSIDE THE HEART OF FONTAN

Once a single ventricle goes into the Fontan correction, we usually feel that the woes for patients lie outside the heart. We had a 12-year-old with Fontan completion done 5 years back. This child came with a new cardiac murmur, not documented in the previous records. On echo, we found a significant subaortic obstruction! I had not come across this earlier. This actually poses a new issue for the patient. Since the obstruction was moderate, the surgical team suggested close follow up. If this becomes severe, what would be the plan? Is going inside the Fontanised heart simple? How frequent are such complaints? Our experience with Fontan is not huge. Can anyone with more experience help us in this?

MONOCUSP

We had some heated debates and discussions on the utility of monocusp valve in intracardiac repairs of tetralogy? Few argued for long-term benefits and few for short-term. Surgeons discussed the risk-benefit ratio of monocusp valve. However, at the end of all these, no one was ready to change their views and opinions. That left most of the simple audience with more confusion and no conclusion. Can the readers put up their opinions in this issue and get us better understanding?

FONTAN WITH HEART BLOCK

Sinus rhythm is one of the Choussat’s criteria for Fontan completion. We had a 9-year-old boy with BD Glenn shunt done outside 5 years back. He had NYHA class III symptoms. During OPD evaluation, he had an ECG which documented sinus rhythm. He was catheterised and the pressures were OK for Fontan completion. However, in the ward, we documented slow heart rate and Holter monitoring showed intermittent A-V dissociation. Surgeons opined that the Fontan completion is still possible with DDD pacemaker insertion simultaneously. This was news to us. Is it done? Is it acceptable? Please let us know about your opinion and experience.

STUBBORN PA

We had a 6-year-old who had undergone a PA banding for multiple VSDs at an outside hospital few years back. The same hospital did a PA de-banding and closed a large upper muscular VSD at the same setting about one year back. When this child came to us, we were surprised to find few sizeable VSDs and a significant gradient across the MPA segment. The operative notes at outside hospital had clearly stated PA de-banding. But, our echo could still pick up a constricted segment in the MPA prior to bifurcation. On cath, we found this narrow segment, which had cicatrised and did not re-open following de-banding. As for the residual VSDs, our expert surgical team was confident that all of them can be dealt with. Hence, we decided for a resection of cicatrised MPA segment and closure of VSDs. How common is this cicatrisation at PA band level? Although we perform good number of PA bands, we at NH had never witnessed this complication. Are such lesions innate to few patients or is it widely seen? Please let us know your experiences on this.

It is time to congratulate Dr Shwetha Nathani, our fellow for the last two years for having successfully completing the Fellowship FNB exam in Pediatric Cardiology. All the good luck for her bright future.
It is time to mourn another departure. Our beloved echo technician, Mrs. Harini is moving to Chennai city for good. We all miss her expertise and keen acumen. Good luck wherever you go.

Pen in your criticisms at comments box or to drkiranvs@gmail.com Shall get back shortly.

Regards

Kiran

Sunday, May 15, 2011

Oops!
Five months that I have updated anything in the blog!!
Sincere apologies.
I know lot of readers have stopped checking the blog. I know I have been unfaithful!!
There were times of busy deadlines, extracurricular works, depressions, blocks, fights, heart-breaks and so on. But none of them can explain the actual reason for the absence of updates: It is pure laziness on my part.
Also, lack of responses from the readers was negative impetus.
One of my teachers suggested me: do it for yourself and be happy if few more get benefitted.
But, showtime spirit is not in favour of it!!
I figured out few ways I can be more consistent. First was restructuring the blog.
I shall continue this blog with pure Pediatric Cardiology material. Shall try to make it more dense and focussed. It should serve for those into this subject or have serious interest in the field.
That actually takes away a substantial amount of readership, mainly – paediatricians. To compensate, I had to think of few ways out:

1. Proposal to start an exclusive interactive blog on Pediatric cardiology for Pediatricians. In this, we would touch common cardiac problems of children which are of much interest and frequency to paediatricians. This blog which is shaping up at present, tries to make an interactive forum with readers, inviting questions from them and giving answers, putting up practical tips on diagnosis and management. I shall give the info shortly.
2. Got a proposal to start one book-club blog! This would be pure non-academics. It aims at getting the readers of blog to write on what interesting non-academic work they have read. It can be a present reading or even a book that had a large impact on them in the past. Purely literature and anything other than politics and religion!!

Working on these ideas have got me an excuse not to write for the present blog. But, I could not avoid the temptation of keeping this blog alive. Hence, I aim to continue this with as much precise info as possible.

I have cut away the segments on articles, reviews and pearls. So, what remains in the blog is purely interesting learning discussions. I shall try to update them as and when possible.

With this prelude, let me continue to the main segment: Interesting learning scenarios:

PRESSURE AND POWER
It is often said that the left ventricle in Ebsteins anomaly gets jeopardised due to innate structural reasons and lateral pressure from atrialised RV. Can the low pressure atrialised RV exert sufficient power to deform the mightier LV? Is the phase of cardiac cycle in which the events occur responsible for such behaviour? If there is space compromise, wouldn’t the low pressure chamber suffer more than the high pressure one? What is the take of readership on this? Please let me know.

DEVICE REGURGITATION
What is the incidence of aortic valve regurgitation following VSD device closure? I would presume it is rare. The scepticism on perimembranous VSD devices are always to do with conduction blocks than aortic valve. Also, it is largely in the case selection. We are always concerned about the distance between VSD and the valves. If a perimembranous VSD device has resulted in mild+ AR, how should it be tackled? Should we just follow it as any other AR, watching for progress and intervening at the right time? Or, should we be aggressive because we have a prosthetic material impinging on the valve and deforming it? If the readers have come across such instances, please enumerate your experiences for others. Otherwise, what is the logical conclusion? We wanted to wait, but surgeons advised us to get the device out. What would your say be?

WHATS IN A NAME?
We had an interesting observation. It was a 5-year-old asymptomatic child with bilateral SVC. However, the LSVC showed flow away from the heart and RSVC was into the heart, with a proper H-communication. The pulmonary veins were normal and all of them were draining effortlessly into LA. We ruled out TAPVC, PAPVC and levo-atrio-cardianal vein. So, what explains the reversal of flow in LSVC. On careful review echo, we could trace the reversal till the H-communication (innominate vein), but the flow from the other end of LSVC was normal till the innominate vein! So, it is as if the innominate vein receives something from heart, apart from its own flow from head and neck. We traced the LSVC into the heart. It used to get blurred by the time we reached the RA. Finally we could figure out that the opening of coronary sinus into the RA was atretic! The cardiac venous flow came into coronary sinus and had a parallel vent in the form of LSVC. Thus, coronary venous flow ascended via LSVC, reached the incidental H-communication, went into the RSVC to eventually enter the RA, unobstructed! Our surgeons claimed that such lesions do exist and they have seen them earlier also. They also claimed that such a lesion has a name. We could not get this eponym. If anyone knows what this combo is called, can you please enlighten us? We did nothing for this patient, as the kid was totally symptom-free. Should we do something? Please let us know your opinion.

EDP IN DISTAL BLOCKS
How pertinent is the EDP in the presence of distal obstruction? We had a 4-year-old with moderate ASD and pulmonic stenosis. One of our consultants felt that the RV not dilated upto the expectation and advised cath study. In the cath, mean gradient across the pulmonic valve was 50mmHg, but the RV EDP was 18mmHg. I was not sure if this EDP reading should be given importance when there was a distal obstruction. Finally, the advice was to get a BPV done and re-assess the ASD. What is the yield of cath pressure data in the presence of such combination lesions? Please let us know your ideas on this.

STEALING BY FISTULA
We do come across few cases of coronary-cameral fistula in young children. We generally go by the volumes and make a decision whether it should be intervened or not based on the chamber dilatation. Do these fistulae cause coronary steal? How do we know it in younger children? Is thallium study useful when there is no wall motion abnormality on echo? I have rarely seen anyone deciding these lesions giving weight to potential steal. Please let us know your take on this.

Let us meet again with another five learning scenarios in short time. Before parting: welcome to our new NH Pediatric Cardiology fellows: Dr Arun Bableshwar, Dr Rahul Saraf, Dr Devprasath and Dr Kshitij Sheth. Hope you will have exciting learning and formative phase as pediatric cardiologists at NH. Also, good luck to Dr Shwetha Nathani – for her fellowship exit exam this month end at Escorts, New Delhi. We wish her the same success as she had for gold-medal winning case-presentation performances at various centres across India.

As usual, please put down any suggestions to drkiranvs@gmail.com or in the comments box

Regards

Kiran