Monday, January 3, 2022

Apex beat in Aortic stenosis vs regurgitation


Clinical pearl: Retroperitoneal hematoma


Vascular access during cardiac catheterization (in cases of myocardial infarction, for example) obtained through femoral artery above the level of inguinal ligament may lead to retroperitoneal hematoma due to arterial puncture.

Sunday, January 2, 2022

DRESS syndrome and Dressler's syndrome - what's in a name?


DRESS syndrome and Dressler's syndrome - what's in the name?

MCQ: Carbamazepine

Q1) Which of the following statements is true about carbamazepine:-
A) It is indicated in complex partial seizures.
B) It is an enzyme inhibitors
C) It can cause megaloblastic anaemia
D) It is the drug of choice for status epilepticus.


So, the answer to the above question is an option 
A) It is indicated in complex partial seizures.

Let's get started with Carbamazepine:-
It is an antiepileptic drug that acts by lengthening the inactivated state of the Na+ channel. 
1) DOC for Partial seizure/trigeminal neuralgia.
2) Bipolar disorder.
3) Acute mania
4) GTCS.

Let's rule out other options:-
Option B) It's an enzyme inducer. It is a substrate as well as inducer for CYP3A4 and CYP2C9. Oxcarbazepine is a less powerful CYP enzyme inducer.

Option C) Carbamazepine causes agranulocytosis or aplastic anaemia and not megaloblastic anaemia.

Other side effects include:
1) Hyponatremia: Delayed and more common in the elderly. Risk is higher in Oxcarbazepine.
2) Hypersensitivity
4) Hepatoxicity 
3) Steven Johnson syndrome (Associated with HLA-B 1502 gene)
4) Ataxia 
4) Blurred vision/ Diplopia 
For the last two side effects, we need TDM for adjusting the dose. Remember, Ataxia and Blurred vision is not a Idiosyncratic reactions.

Let's do questions related to Carbamazepine!

Q1) What adverse effect is risked to ongoing valproate therapy?


Q2) A cancer patient is on anticancer drugs (vincristine etc) and develops multiple episodes of seizures, refractory to diazepam and lidocaine. Blood tests show elevated ADH and euvolemic hyponatremia. Which drug can be used to treat this patient?

- You can't use Carbamazepine because it causes increase sensitivity of renal tubules to ADH levels. 
In this case, we use Phenytoin which causes a decrease in ADH secretion and corrects hyponatremia.


Wednesday, December 29, 2021

Introducing Cardiowesome

Hi everyone, 

As you already know I have started my Cardiology Fellowship this year. I'm going to post a lot of blogs on cardiovascular diseases that might of not be palatable for medical students. Only some of these posts maybe helpful (pharmacology related, EKG ones, and basic pathophysiology of cardiovascular diseases). 

I understand that the majority of my posts will be limited to a specialized group of cardiologists, echocardiographers, emergency medicine physicians, critical care professionals, POCUS users, electrophysiologists, heart failure specialists, and interventional cardiologists.

This is why, I'm introducing a new label on the medicowesome blog called cardiowesome. These are advanced posts targeted for cardiology fellows and trainees.

I hope you enjoy reading them and learning with me. 

-IkaN (Nakeya Dewaswala Bhopalwala) 

S' Tissue Doppler Imaging - Derived Tricuspid Lateral Annular Systolic Velocity mnemonic

S’ Wave: Tissue doppler imaging-Derived Tricuspid Lateral Annular Systolic Velocity

S’ value less than 9.5 cm/sec indicating RV dysfunction. Mnemonic... If you stare at the number long enough you'll see 9.5 in it lol. 

The first peak above baseline that is timed with the QRS represents isovolumetric contraction and not the tricuspid annular velocity.

-IkaN (Nakeya Dewaswala Bhopalwala) 

Relative wall thickness 0.42 mnemonic

The RWT reports the relationship between the wall thickness and cavity size. It is an index of LV concentricity. 

The golden number to remember for RWT is 0.42 as it allows further classification of LV mass increase as either concentric hypertrophy (RWT >0.42) or eccentric hypertrophy (RWT ≤0.42). 

Since there are so many numbers to remember in echocardiography, I made a mnemonic for RWT. 

Relative = 0 (Relative zero)
Wall = 4 (4 letters in the word wall)
Thickness = 2 (2 strokes in the letter T) 

Hope this helps! 

-IkaN (Nakeya Dewaswala Bhopalwala) 

Tuesday, December 28, 2021

Monday, December 27, 2021

Relative wall thickness on echocardiography

Relative wall thickness (RWT) is calculated as two times posterior wall thickness (PWT) divided by the left ventricular internal diastolic diameter (LVIDd). 

RWT allows further classification of LV mass increase as either concentric hypertrophy (RWT >0.42) or eccentric hypertrophy (RWT ≤0.42).

-IkaN (Nakeya Dewaswala Bhopalwala) 

Infective endocarditis vegetations - which side do they develop?

Infective endocarditis vegetations tend to develop on the upstream side of the valve (flow side) which is typically tend to be the lower pressure side. These are the ventricular side of the aortic valve and the atrial side of the mitral or tricuspid valve. 

Image shows parasternal long axis view on echocardiography showing vegetations on the mitral and aortic valve (green vegetations because vegetables are green lol!)