Dr. Usman's Cardiology Notes

What is PCSK9?  Our liver makes a protein called proprotein convertase subtilisin/kexin type 9 (PCSK9). PCSK9 regulates how many LDL receptors you have. Studies have shown that if you have naturally high PCSK9, you are more likely to have high cholesterol. PCSK9 inhibitors decrease LDLR degradation by PCSK9, and thereby improve LDL-C clearance and lower plasma LDL-C Here are some landmark trials on PCSK9 inhibitors: Landmark Trials on PCSK9 Inhibitors 1. *FOURIER Trial (2017)*: Evaluated the efficacy and safety of evolocumab (Repatha) in reducing cardiovascular events in patients with established cardiovascular disease. Results showed a 15% reduction in major cardiovascular events. 2. *ODYSSEY OUTCOMES Trial (2018)*: Assessed the efficacy and safety of alirocumab (Praluent) in reducing cardiovascular events in patients with acute coronary syndrome. Results showed a 15% reduction in major cardiovascular events. 3. *SPIRE-1 and SPIRE-2 Trials (2014)*: Evaluated the efficacy and safet...

Here are some of my thoughts on it !  Vagal tone is a measure of the activity of the vagus nerve. vagotonia is a condition where the vagus nerve is excessively excitable! while Hypervagotonia is relatively rarer , which results in sinus node dysfunction and can result in significant symptoms!!  A common misunderstanding among most of us is of autonomics believing that the nerve structures are either sympathetic or parasympathetic!  Hence the commonly used term vagal tone is generally refer to describe the level of activity in the para sympathetic system  Where as in reality the vagus and all the other cardiac nerves carries /contain both sympathetic &parasympathetic components.  Vagal effects  1. Vagal activation simultaneously affects both the sinus and AV nodes.  The resulting ECG can include  sinus slowing / Sinus arrest & varying degrees of AV node block.  2. One of the most commonly seen hallmarks changes of vagally mediate...

  Apical four chamber view of echocardiogram showing Atrial Septal Aneurysm bowing into left and right atria like a swing. As its movement is bi directional, its type 5. Classification of Inter atrial Aneurysm: type 1R: bulging is in the right atrium only type 2L: bulging is in the left atrium only type 3RL: major excursion bulges to the right atrium and the lesser excursion bulges toward the left type 4LR: maximal excursion of the atrial septal aneurysm is toward the left atrium with a lesser excursion toward the right atrium type 5: atrial septal aneurysm movement is bidirectional and equidistant to both atria during the cardiorespiratory cycle. Visit Echo Library>>

In pa­tients with con­gen­i­tal com­plete or high de­gree AVB, pac­ing is rec­om­mend­ed if one of the fol­low­ing risk fac­tors is pre­sent: a) Symp­toms b) Paus­es >3x the cy­cle length of the ven­tric­u­lar es­cape rhythm c) Broad QRS es­cape rhythm d) Pro­longed QT in­ter­val e) Com­plex ven­tric­u­lar ec­topy f) Mean day­time heart rate <50 b.p.m. Reference: ESC Guidelines for Pacing 2021 Thanks 

  Lead­less pace­mak­ers should be con­sid­ered when: no up­per ex­trem­i­ty ve­nous ac­cess ex­ists,  risk of de­vice pock­et in­fec­tion is par­tic­u­lar­ly in­creased, and in  pa­tients on haemodial­y­sis. Watch the above video to get an idea how Leadless Pacemaker looks like on fluoroscopy. Leadless Pacemakers: A Revolutionary Advancement in Cardiac Pacing Leadless pacemakers, also known as self-contained or miniaturized pacemakers, represent a significant breakthrough in cardiac pacing technology. These tiny devices are implanted directly into the heart, eliminating the need for leads, which can often be a source of complications. In this article, we will delve into the world of leadless pacemakers, exploring their design, benefits, implantation procedure, and potential complications. Design and Functionality Leadless pacemakers are small, self-contained devices that combine the pacemaker generator and electrode into a single unit. They are typically 1-2 cm in length...

  Measuring right ventricular systolic pressure (RVSP) on echocardiogram is a crucial assessment for evaluating pulmonary hypertension and right ventricular function. Here's a step-by-step guide on how to measure RVSP on echo: Views and Measurements 1. *Tricuspid Regurgitant Jet*: Obtain a continuous wave Doppler (CWD) tracing of the tricuspid regurgitant jet in the apical 4-chamber view or the right ventricular inflow view. 2. *Peak Velocity*: Measure the peak velocity of the tricuspid regurgitant jet (Vmax) in meters per second (m/s). 3. *Pressure Gradient*: Calculate the pressure gradient across the tricuspid valve using the modified Bernoulli equation: ΔP = 4 × Vmax^2. 4. *Right Atrial Pressure (RAP)*: Estimate the RAP using the inferior vena cava (IVC) diameter and collapsibility. A RAP of 5-10 mmHg is commonly assumed. 5. *RVSP Calculation*: Add the estimated RAP to the pressure gradient to calculate the RVSP: RVSP = ΔP + RAP. Formula RVSP (mmHg) = 4 × Vmax^2 (m/s) + RAP (mmH...

 The Q or the q wave on the surface ecg can sometimes proves very dodgy!!!   So let’s look at the normality or how & why q  is recorded on the surface ecg !!!! Here some of my comments consolidated on this aspect of ecg Normally q is The first or the initial deflection of QRS and results from the rapid depolarisation of the thin walled septum which is occurring from the left to the Right ventricle and this is inscribed in most of the surface ecg leads!!!! B. Normality Small Q are defined as less than 0.03 seconds in duration, or two small squares or less in amplitude & Generally should be no larger than 25% of the associated R. 1. Normality in all leads except V1 through V3, where they are always pathological 2. A Q of any size is generally normal in limb lead III (is varying with respiration) 3. laterally in the chest leads, reflecting left-to-right septal depolarization. 4. A large Q May be seen in lead aVR (as it looks at the endocardial of the heart, it regist...