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...

  Rheumatic mitral stenosis is a serious heart condition that affects millions worldwide. It occurs when the mitral valve, which regulates blood flow between the left atrium and left ventricle, becomes narrowed due to rheumatic fever. This narrowing obstructs blood flow, causing the left atrium to dilate or enlarge. Above Video is showing Rheumatic Mitral Valve Stenosis with dilated LA. Symptoms People with rheumatic mitral stenosis and a dilated left atrium may experience: - Shortness of breath (dyspnea) during physical activity or at rest - Fatigue and weakness - Swelling in the legs, ankles, and feet (edema) - Palpitations or irregular heartbeats - Coughing up blood or pink, frothy mucus Diagnosis Diagnosing rheumatic mitral stenosis involves: - Physical examination and medical history - Echocardiogram (ultrasound of the heart) to visualize the mitral valve and left atrium - Electrocardiogram (ECG) to assess heart rhythm - Chest X-ray to evaluate lung congestion Treatment Treatm...

  ECG Showing Third Degree AV Block   Complete atrioventricular (AV) block, also known as third-degree AV block, is a rare but serious cardiac condition where the electrical signals between the atria and ventricles are completely blocked. This blockage prevents the ventricles from receiving the necessary electrical impulses to contract and pump blood effectively. Causes of Complete AV Block Complete AV block can occur due to various reasons, including: 1. Age-related wear and tear: The AV node can degenerate over time, leading to complete blockage. 2. Cardiac diseases: Conditions like coronary artery disease, cardiomyopathy, and myocarditis can damage the AV node. 3. Infections: Certain infections, such as Lyme disease, can cause inflammation and damage to the AV node. 4. Medications: Certain medications, such as beta-blockers and calcium channel blockers, can slow down or block electrical conduction. 5. Congenital heart defects: Some people are born with AV block due to conge...

This ECG is showing Atrial focus running around 240/min,  two or more ventricular foci competing , seems isorhythmic AV dissociation. So it's sinus tachycardia with Bifascicular block pattern Right Bundle with left axis and p occurs at constant Rate but with ventricular ectopics occurring in bigeminal and trigeminal pattern with no fixed PR interval related hence favoring ventricular ectopic beat with Left ventricular outflow origin. The Ventricular ectopics or ectopies creates lots of concerns , confusion and issue with labelling or terminologies and above all treatment / managment !!!!!  Mostly these are over concerns however sometimes the concern can be very genuine esp in case of them occurring as closely coupled !!! To better identify the Ectopies , the following needed to be known Shortly coupled Ventricular Ectopy (VE) that seems to be lodging onto the preceding T wave (the famous term R on T) May actually be indicative of electrical instability of the heart and de...

LA anatomy on Cardiac CT showing four Pulmonary Veins draining into LA Atrial Fibrillation Cryoablation: Indications 1. Symptomatic paroxysmal or persistent atrial fibrillation (AF) 2. Failed anti-arrhythmic drug therapy 3. Heart failure or reduced left ventricular function Procedure 1. Electrophysiology study (EPS) to identify left-sided pathway 2. Transeptal puncture and transseptal sheath placement 3. Cryoablation catheter (e.g., SL1) placement in left atrium 4. Cryoenergy application to pulmonary veins, posterior wall, and other targeted areas Key Ablation Targets 1. Pulmonary veins (PVs) 2. Posterior left atrial wall 3. Mitral isthmus 4. Left atrial appendage Benefits 1. High success rate for paroxysmal AF 2. Improved symptoms and quality of life 3. Reduced risk of stroke and heart failure hospitalization Risks and Complications 1. Cardiac tamponade 2. Stroke or transient ischemic attack (TIA) 3. Pulmonary vein stenosis 4. Atrio-esophageal fistula (rare) Post-Procedure Care 1. Mon...