Posted in Uncategorized on January 1, 2023|
Wishing every one of you an Enlightening New year. As we begin a new journey around the sun, yet another time, let us re-dedicate ourself, to use science, for the welfare of our planet & people.
Thank you , for visiting this site and make all its worth.
Posted in Atrial fibrillation, Mitral stenosis, Uncategorized, tagged Atrial mass in mg, LAH in mitral stenosis, left atrial hypertrophy, left atrial mass, thickness of left atrium on December 20, 2022|
I will go with the last response. As for as I understand, we have never quantified Atrial muscle mass properly even in normality. One may be tempted to think there is no purpose to measure it, other than academic reasons. The fact that the incidence of atrial fibrillation in mitral stenosis is not linearly correlating with LA size makes us think, LA mass (Virtual LAH) may have a say in triggering AF.
This post is meant for cardiology fellows. Maybe someone can do a study on this by measuring LA mass pre and post-PTMC, we might get an idea about regression as well. Meanwhile, we are well versed with infiltrative diseases like atria like amyloidosis that can mimic LAH. Currently, we realize fatty infiltration of LA is the common trigger for AF in varied populations.
By the way, readers are welcome to post any specific formula to measure LA mass if they come across .
Reference
A good review of LA anatomy.
Posted in Uncategorized on November 29, 2022|
Posted in Uncategorized, tagged anemia in cardiac failure on November 19, 2022|
HF is the inability (or reduced ability) to supply oxygen and other nutrients to fulfill the body’s demands. In the process, the heart either fights or flights, and results in symptoms due to hemodynamic alterations, or adversities of neuro-hormonal activation.
Now, what is Anemia? Anemia is a condition with reduced or dysfunctional RBCs. that directly interferes with oxygen delivery to tissues. It is not at all a coincidence, the core functions of the heart and blood are strikingly similar and intertwined. While the heart is the powerhouse of the circulatory system, without good-quality blood, the greatness of this vital organ becomes redundant.
A failing heart & compromised blood, throws up a double challenge, to the fundamental function of the circulatory system and results in impaired cellular oxygen delivery.
Fortunately, RBC and Hemoglobin have an adequate reserve, and real metabolic issues happen only after a 30 % reduction in hemoglobin. During this time the heart works more to compensate by maintaining high output. When HB falls less than 6 to 7 grams the heart itself suffers from hypoxia and goes for intrinsic failure. So, when anemia coexists with cardiomyopathy imagine the tissue’s plight.
Anemia in Heart failure
While there are many links between anemia and heart failure few things are worth emphasizing. It can be discussed in 4 categories.
*Category 2 is often missed, while category 3 is often ignored
Prevalence of anemia in HF.. Up to 30%. (Iron deficiency anemia is the most common)
Diagnosis: Criteria Ferritin less than100 or 100-299 μg/L with transferrin saturation <20%).
What is the optimal Hb %? Should be 13 grams
Iron deficiency is much more than anemia
It is worthwhile to go back to the basics, anemia is just one aspect of iron deficiency. Humans live their life, essentially inside the breathing chambers of mitochondria in each of the 12 trillion cells. Without an adequate iron supply, the citric acid cycle will come to a creeping halt. It is now recognized, altered mitochondrial function is one of the key peripheral defects in HF. (Ref 1) Iron deficiency could be an Incidental marker for a more important tissue deficit elsewhere.
What do the trials say about the role of routine Iron supplements in HF?
As usual, trials blink with data on either side of the truth. Small studies suggested benefits. But large studies with Iron supplements and Erhytopoitn analogs failed to show benefits. IRON-OUT, RED -HF (Ref 2,3) . But in a popular study from the Lancet , showed ferric carboxymaltose improved the outcome. (Ponikowski P,l. Lancet. 2020 Dec 12;396(10266):1895-1904).
Final message
We, as modern-day cardiologists are always pre-occupied with measures to improve LV ejection fraction at any cost (Since we fell into a false knowledge trap of defining HF solely on the basis of EF% ) To make HF patients walk 30 meters extra in a 6-minute walk test we have complex and costly procedures like CRT, Mitra clips, and IAS flow regulators, etc.
However, experience tells us there are many parameters other than EF that can improve functional capacity and quality of life. Breathing exercise is the best example. Let’s add one more to this list. A simple correction of anemia with iron can make your cardiac failure patient walk many blocks more. Trials are not consistently confirming this though. Don’t bother them, just have a try. If prescribing tablet iron without evidence bothers you with scientific guilt, ask your patient to take a diet with rich iron content and see the difference.
For advanced readers
Anemia and Aortic afterload: The apparent advantage
There is one curious concept. Anemia makes the blood thin. Reason lowered viscosity. As a consequence afterload falls. , hypoxia-induced peripheral vasodilatation and enhanced nitric oxide activity also contribute to this. Vasodilatation also involves the recruitment of microvessels and, in the case of chronic anemia, stimulation of angiogenesis. So, anemia apparently has a double edge, and one of them seems to be beneficial.
We must also beware, the risk of iron overload is genuine in some of these patients with HF. This makes us wonder, in ancient times venesection was used for so many undisclosed illnesses, which might include heart disease as well.
Reference
Posted in Pace maker Tips and tricks, Uncategorized, tagged pacemaker mode selection, vvi vs ddd pacing on November 3, 2022|
We have enough evidence to question the superiority of the presumably best practice in cardiac pacing namely dual chamber pacing. Apparently, the DDD failed to show gross benefits in both AV block as well as sinus node dysfunction. (UKPACE, MODE-Selection Trial) in studies done nearly two decades ago.
It is 2022. Here is one more study in the Indian heart journal, coming up from JIPMER Pondycherry,on this concept. It is an intelligently designed cross-over study. The same patients were switched between DDD and VVI modes. This study reaffirmed the lack of appreciable hemodynamic and clinical benefits with DDD mode yet again.
We have also contributed a little on this issue. It was found cardiac failure in VVI pacing was not a real big issue in the long-term follow-up. We presented and published in world congrees of cardiology Dubai 2012, and Circulation journal.
How is that? A dual chamber pacer with AV synchrony fails to show a hemodynamic benefit?
The answer is simple..VV desynchrony is a common denominator for both VVI and DDD pacers. Providing AV synchrony without VV synchrony doesn’t make real sense in the long term to overcome the altered physiology, Still, DDD pacing continues to enjoy a popular mandate by hiding behind a vague outcome measure called quality of life.
What is the physiological pacing then?
Just because, DDD and VVI pacers are equipoise, can we presume the new pacing kid LBBB pacing would be physiological? We wish so, but unless and until we replicate the entire conducting system right from SA, and the AV node which includes many miles length of delicate Purkinje cables, every pacing system we use is currently pathological. (If that sounds too harsh, let’s make it non-physiological)
Having said that, VVI pacing is one of the most remarkable Inventions in medical science since the last century, that plays God’s own function and gives a new lease of life to all those patients with critical AV blocks and trouble some SNDs.
Final message
It may be difficult to digest for true scientists. Restoring the atrial booster pump is not bringing in the desired benefits. It is clear that VVI pacing will never become obsolete. This fact was established long before. We must argue and wonder, why we need to keep proving a scientific truth again and again? There could be a good justification too. Real-time cardiologist behavioral patterns clearly tell us, as a genre, they often struggle to get detached from futile modalities even after good published evidence (PCI for CTO, Revascularisation for Ischemic DCM, are a few more examples)
Posted in Uncategorized, tagged coronary artery damping and ventricularization, Damping and ventricularization, ventricularization on October 26, 2022|
“Never take your eyes off the monitor and the pressure curve” It is one of the basic instructions given to the fellows & technicians as they start engaging the coronary artery and Intubating the coronary ostium in their early cath lab postings. There are two commonly heard noise bites in the cath lab for the beginner. 1. Damping 2.Ventricularization.
Damping
It is the deformation of the normal arterial pressure curve, with a blunting of both systolic and diastolic pressure that drops compared to aortic pressure. Extreme damping can mimic a straight line with few wavy undulations. It means the forward flow is impeded as the catheter might be blocking the coronary flow at least partially, if not completely. Immediate pull back and adjustment of catheter is required to prevent adverse events that includes cardiac arrest. (Of course, catheter kinks, blocks, and air in a circuit are to be ruled out first)
Mechanism of damping
Unique features in RCA damping
In RCA, damping could simply mean it has engaged conus branch. Damping is more common in RCA and it tends to get sucked in deeper for two reasons. We know , the RCA catheter is not preformed, the tip seeks the ostium, looking for a negative pulling pressure from within the RCA. Further, unlike the LCA, the flow in RCA is continuous in both systole and diastole. Another possible factor is the inspiratory swings of RV transmural pressure is more than LV.
Transient bradycardia due to compromise of SA /AV nodal flow is common. It is well known that RVOT is a thin and VPD-prone zone , compared toLVOT. Hence it is more vulnerable to ischemia and triggers a VT/VF if damping is prolonged in RCA.
Ventricularization
This is tracing during the engaging of a left main ostial stenosis. The diastolic pressure drops on the third complex, and the pulse pressure becomes large . Note the small “a ” wave slur as well near the diastolic nadir. The aortic pressure curve is restored once tip adjustment is done. Image courtesy Thoraci key.https://thoracickey.com/coronary-angiography-3/
It simply means the pressure curve starts looking like a ventricular pressure curve. The issue is not that simple. It is still a mystery, how could the coronary artery pick up ventricular pressure. In fact, it doesn’t. It was initially thought to be either deformed aortic pressure or a wedged coronary artery pressure .or a combination of the two.
It s now accepted it’s due to total occlusion of the coronary artery the ventricle muscle sucks the catheter and pulls the diastolic pressure markedly down even lower than LVEDP. The systolic pressure also falls but not much of it is noticed.The fact that ventriculaization happens less commonly with RCA gave us a clue to its mechanism. (Most of the RCA travels over RV and since RV muscle mass wields less negative suction force )
How to differentiate true LV location from ventricularization?
If the catheter enters the LV cavity, the systolic pressure will match that of aortic systolic pressure and diastole will reach the LVEDP. In ventricularization there can be a slight drop of the systolic pressure, but the diastolic is the one goes far down. Further, the ascending limb is shallower, the descending limb is steeper in coronary ventricularization. Apart from this if we carefully look “a” waves will be visible in ventricularisation in the late diastolic phase.(Could it be the modified Incisura ?)
Relationship between damping and ventricularization ?
Discussing damping and ventricularization together is more of an academic tradition. Please realize, both may not be two exclusive entities. In fact, they can occur at the same time, or sequentially or interchangeably if the catheter tip swings back to partial to total occlusion and vice versa. if complete wedging occurs it becomes ventriculariszation.
Which is more dangerous damping or ventricularization?
How can you ask such a question? Both can be harbingers of serious hemodynamic issues if ignored and accidentally injected, The dreaded one is the dissection. Apart from mechanical injury, Injecting dye during damping or ventricularization causes dye stasis, and may trigger VT or VF if it is prolonged. There is a biochemical component too. As the contrast swirls around for a few seconds it can cause transient hypocalcemia by chelating this cation.
I don’t have a clear answer to the above query. In my understanding, forceful injections during ventricularization could be more riskier as injection happens over a total occlusion in a wedged position and dye has direct access to the microcirculatory bed. It is true, expert cardiologists do shoot in damped positions occasionally to see the anatomy quickly. They may be your mentors, still don’t learn this trick, till you become a true expert (Famously referred to as hit and run technique)
How to overcome these pressure curve malformations?
Most times, it is a simple technical artifact issue. Deep Intubation with an oversized catheter could be the commonest cause in the otherwise normal coronary artery. Proper catheter sizing, angle of alignment, and adjustment is the key. If it is a spasm nitroglycerine might help. Using catheters with side-hole perfusion catheters is an option in difficult anatomies. Mind you, side holed guide is a two-edged weapon, it can mask true hemodynamic adversaries by falsely showing a good aortic pressure tracing.
(One of the good cath lab habits is to have a look around the patient face at least once in a while when performing complex procedures. We have many times recognized serious hemodynamic issues only after the patient starts behaving bizarrely due to hypotension. Pressure curves can fool you, but patience will never.)
Final message
Recognizing abnormal waveforms during engagement is a crucial step for the beginner (Experts can’t ignore though) Please remember LMCA stenosis should be the default alarm for any damped pressure curve as you engage the LCA. If you take things casually consequences can be lethal for the patient as well as the consultant in charge.(Fellows can’t take it lighter though). It is an undisclosed fact, that many of the serious complications in the cath lab happen not out of ignorance or lack of expertise, but because of ignoring some basic principles and lack of cath lab discipline.
Reference
1.Baim DS, ed. Grossman’s Cardiac Catheterization, Angiography, and Intervention. 7th ed. Philadelphia, PA: Lippincott Williams & Wilkins, 2006. 2. Judkins MP. Selective coronary arteriography, a percutaneous transfemoral technique. Radiology 1967;89:815.
2.T Pacold I, Hwang MH, Piao ZE, . The mechanism and significance of ventricularization of intracoronary pressure during coronary angiography.Am Heart J. 1989 Dec;118(6):1160-
Posted in Uncategorized on October 17, 2022|
Posted in Uncategorized on October 13, 2022|
Posted in Uncategorized, tagged criteria for hfpef, esc guidelines on hfpef, HFpEF on October 12, 2022|
Though all of us are aware, the incidence of heart failure is increasing exponentially and is the leading cause of global disease mortality, what we fail to understand is, we still lack a good definition cardiac failure.
Defining HF based on EF% is convenient but adds more complexity, and is less scientific too. Still, as of now, we have adopted this. I think, one of the important factors that apparently increased the incidence of HF is the creation of an entity called HFpEF. (Formerly diastolic heart failure)
Thanks to ESC, we have a consensus document, which has defined HFpEF based on functional, morphological, and biochemical features. This is a more refined model from the original Mayo clinic H2FpEF score.
Both are given below.
Final message
It is back to basics & time to dig into the fundamentals, of what exactly we mean by heart failure. Is the elevation of LV filling pressure alone sufficient? Should it happen at rest or at exertion, and whether neuroendocrine activation is necessary? Is RASS activation similar in both HFrEF and HFpEF? Try to find the answer to this. How often does HFpEF fulfill Framingham’s criteria of HF.? ( Löfström et al ESC Heart Fail. 2019)
Trying to understand the nuances of HFpEF, I think, we can make a statement,- HFpEF can not be diagnosed without pulmonary hypertension. It makes a lot of sense the P in the H2FpEF scoring system denotes PH, however, It is assigned only a single point, which needs revision. In fact, there is a strong case to argue and make it an essential criterion.
Paradoxically & curiously HF with reduced ejection fraction (which is the most common form of HF) doesn’t require the presence of PAH to diagnose it. This issue may also be examined.
Reference
Dr.S.Venkatesan MD 