Dr. Usman's Cardiology Notes

  AV Node in the Triangle of Koch  Here’s a detailed note on the Triangle of Koch, important in cardiology and electrophysiology: --- Triangle of Koch – Overview The Triangle of Koch is an important anatomical landmark located in the right atrium of the heart. It serves as a guide to locate the atrioventricular (AV) node, which is crucial for the cardiac conduction system. Knowledge of this triangle is essential in electrophysiology procedures such as AV nodal ablation, slow pathway ablation for AV nodal reentrant tachycardia (AVNRT), and in avoiding iatrogenic AV block. Anatomical Boundaries: The triangle is defined by three key structures: 1. Tendon of Todaro – a fibrous band running from the Eustachian valve (at the IVC) to the central fibrous body. 2. Ostium of the coronary sinus (CS) – located at the base of the triangle. 3. Septal leaflet of the tricuspid valve – forming the anterior boundary. Thus, the triangle is bounded: Posteriorly by the Tendon of Todaro Inferiorly ...

 Atrial Septal Defect (ASD) Device Closure: A Comprehensive Overview Case Presentation: A 25-year-old female patient presented with complaints of shortness of breath on exertion and palpitations for the past 6 months. She had no significant past medical history and was not taking any medications. Physical Examination: - Vital signs: Blood pressure 120/80 mmHg, pulse rate 90 beats per minute, oxygen saturation 98% on room air. - Cardiovascular examination: Revealed a systolic ejection murmur at the left upper sternal border, with fixed splitting of the second heart sound. - Chest examination: Clear lungs, no peripheral edema. Diagnostic Tests: - Electrocardiogram (ECG): Showed sinus rhythm with right axis deviation and incomplete right bundle branch block. - Chest X-ray: Revealed cardiomegaly with increased pulmonary vascular markings. - Transthoracic echocardiogram (TTE): Demonstrated a secundum atrial septal defect (ASD) with left-to-right shunting, right ventricular enlargement, ...

Mitral Valve Prolapse: A Comprehensive Review Mitral Valve Prolapse (MVP) is a common valvular heart condition characterized by the displacement of the mitral valve leaflets into the left atrium during systole. This article provides an in-depth look at the diagnosis, echo findings, and auscultation maneuvers used to identify MVP. Pathophysiology In MVP, the mitral valve leaflets bulge backward into the left atrium due to: 1. Myxomatous degeneration: Thickening and redundancy of the valve leaflets. 2. Chordal elongation: Stretching or rupture of the chordae tendineae. Echo Findings Echocardiography is the primary diagnostic tool for MVP. Key findings include: 1. Leaflet displacement: > 2 mm displacement of the leaflets beyond the mitral annular plane. 2. Leaflet thickening: Thickening of the leaflets (> 5 mm). 3. Mitral regurgitation: Color Doppler assessment of regurgitant flow. 4. Left atrial enlargement: Enlargement of the left atrium due to chronic regurgitation. Auscultation ...

  Case of Mahaim Fiber pathway related Tachycardia: During atrial pacing, the above tachycardia is induced. In Differentiating wide complex tachycardia following points should be considered. During atrial pacing (the 1st beat), the His catheter has the activation sequence proximal to distal (antegrade His activation). During the 2nd paced beat, the His deflection (on proximal His) gets buried within the ventricle (block of the AV node, maximal preexcitation) and antidromic tachycardia is induced. During tachycardia, the His activation sequence is reversed, and distal His is before proximal His. Therefore, the activation of the His bundle is retrograde during tachycardia, but still before ventricular activation. This is only possible in the presence of an extranodal pathway inserting in the fascicle just below the His bundle, most frequently the right bundle (Mahaim). Careful examination of the sequence of His bundle activation can lead to the correct diagnosis already at first gla...

The Link Between Red Meat and Heart Disease: Understanding the Role of Saturated Fat and TMAO Red meat has long been associated with an increased risk of heart disease, and recent research has shed light on the potential mechanisms behind this link. Two key factors that contribute to this association are high saturated fat levels in red meat and the production of Trimethylamine N-oxide (TMAO), a dietary byproduct formed by gut bacteria during digestion. Saturated Fat: A Contributor to Heart Disease Saturated fat, found in high levels in red meat, can increase the risk of heart disease by: 1. Raising low-density lipoprotein (LDL) cholesterol: LDL cholesterol can accumulate in the walls of arteries, forming plaques that narrow the blood vessels and restrict blood flow. 2. Increasing inflammation: Saturated fat can trigger inflammation in the body, which can further damage blood vessels and increase the risk of heart disease. TMAO: A Hidden Culprit Trimethylamine N-oxide (TMAO) is a dieta...

  Dr. Samuel J. Asirvatham's lecture on Ventricular Tachycardia (VT) provides a comprehensive review of the topic, covering the definition, mechanisms, diagnosis, and management of VT. The lecture is designed to help cardiology fellows and board-certified cardiologists prepare for certification exams. VT is defined and its mechanisms are discussed, including re-entry, triggered activity, and automaticity. Re-entry occurs when an electrical impulse recurrently activates the ventricle, while triggered activity and automaticity can lead to abnormal electrical activity. The diagnosis of VT is covered, including electrocardiogram (ECG) characteristics such as wide QRS complexes, AV dissociation, and fusion beats. The clinical presentation of VT is also discussed, including symptoms and signs. The management of VT is reviewed, including acute management with cardioversion, anti-arrhythmic medications, and ACLS protocols. Chronic management options are also discussed, including implantabl...

  In this MOCK Exam there are twenty five echocardiography cases, each case is of about one to two minutes, with initial half to view the case and in the next half clips are repeated with answer so you can relate the answer with echo clips. Into the world of echocardiography with our comprehensive video series, where we explore 25 intriguing cases, each with labelled findings. This video is perfect for medical professionals, students, and anyone interested in cardiac imaging. What You'll Learn - In-depth analysis of various cardiac conditions through echocardiography - Labelled findings to help you understand and identify key features - Real-life cases to enhance your diagnostic skills We examine a rare condition known as mitral valve arcade. This anomaly is characterized by abnormal chordal structures connecting the papillary muscles directly to the mitral valve leaflets, bypassing the normal chordae tendineae. Echocardiography reveals thickened, dysplastic leaflets with restri...

Usual TPM (Temporary Pacemaker) Showing Dials and Indicators Stimulation Threshold Testing: Set Rate at least 10 beats above patient's intrinsic rate Decrease Output by slowly turning output dial counterclockwise until ECG shows loss of capture. Increase Output by slowly turning output dial clockwise until ECG shows consistent capture. This value is the Stimulation Threshold  Set Output to 2 to 3 times higher than the Stimulation Threshold (Safety Margin) Restore Rate to previous value. Sensing Threshold Testing: Set Rate at least 10 beats below the patient's intrinsic rate. Set Output to 0.1 mA Decrease Sensitivity by slowly turning Sensitivity dial counterclockwise until pace indicator flashes continuously. Increase Sensitivity by slowly turning Sensitivity dial clockwise until sense indicator flashes and pace indicator stops flashing. This value is the Sensing Threshold. Set Sensitivity to Half of the threshold value (Safety Margin) Restore Rate and Output to previous values...

Above video demonstrate the10 Basic Views to master in Intracardiac Echocardiography also known as ICE, presented in simple form with real time images labeled with important structures. Home view is usually the first view when we insert intra-cardiac echo catheter or ICE catheter into right atrium.  Types of Intracardiac Echocardiography:   There are two types of ICE - phased array and radial. ○ Phased array: more common as it creates a view that is easier to interpret as it resembles a TTE or TEE. ○ Radial ICE: greater resolution, but is more difficult to interpret and is best for discriminating near-field structures and therefore requires transseptal puncture to visualize left heart structures. Process: ● Insert catheter through the femoral vein up through the IVC to the right atrium (most commonly), “the home base” for the ICE catheter. The catheter can also be inserted via the right IJ or left subclavian and then through the SVC however this will give “upsidedown” image...

Same Patient with Arm Pulled down towards Knee. If you have difficulty in getting Axillary Access, ask patient or someone to pull arm downward towards knee, as it's occluded in this position sometimes Between rib & Clavicle.

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...

  Ambulatory Blood Pressure Monitoring (ABPM) Device Ambulatory Blood Pressure Monitoring (ABPM) offers several benefits over traditional office-based blood pressure measurements: Benefits & Indications: 1. More Accurate Diagnosis: ABPM provides a comprehensive picture of blood pressure patterns over 24 hours, reducing the risk of misdiagnosis. 2. Identification of Masked Hypertension: ABPM can detect masked hypertension, where blood pressure is normal in the office but elevated at home. 3. Assessment of Blood Pressure Variability: ABPM measures blood pressure variability, which is a predictor of cardiovascular risk. 4. Detection of Nocturnal Hypertension: ABPM can identify nocturnal hypertension, which is associated with increased cardiovascular risk. 5. Monitoring of Treatment Efficacy: ABPM helps assess the effectiveness of antihypertensive therapy and guides treatment adjustments. 6. Reduced White Coat Hypertension: ABPM minimizes the impact of white coat hypertensio...

A 68 year old female with atrial fibrillation and dementia presented to the hospital with sudden onset of dyspnea that had begun 1 hour earlier. Before admission, he had not been taking anticoagulation therapy on the basis of discussions of his preferences with his primary care physician. Physical examination was notable for tachypnea and tachycardia. On chest radiography, the pulmonary vasculature was not visible in the right lung fields. In addition, the right descending pulmonary artery was enlarged. These radiograph findings display Westermark’s sign, which indicates an area of oligemia distal to a pulmonary embolism, and Palla’s sign, an enlargement of the right descending pulmonary artery. Computed tomographic (CT) pulmonary angiography of the chest confirmed the presence of pulmonary emboli in both pulmonary arteries, predominantly on the right side. The CT scan also showed oligemia in the lung parenchyma on the right side. Source: NEJM

Cardiac Cath Practice Cases with Answers:   Basic Views of Coronary Angiogram: Introduction: Coronary angiography is a crucial diagnostic tool used to assess the coronary arteries' health and detect blockages or abnormalities. This procedure involves injecting a contrast dye into the coronary arteries and capturing X-ray images to visualize blood flow and identify potential issues. Understanding the various angiogram views, structures visible, and troubleshooting techniques is essential for healthcare professionals involved in cardiac care. 1. Basic Coronary Angiogram Views:    - Right Anterior Oblique (RAO) View: Provides a clear visualization of the right coronary artery (RCA) and its branches.    - Left Anterior Oblique (LAO) View: Offers a detailed look at the left coronary artery (LCA) system, including the left main coronary artery (LMCA), left anterior descending artery (LAD), and left circumflex artery (LCx).    - Cranial/Caudal Views: These vi...

Cardiac CT is one of six modalities we commonly use to image the heart. Each of these 6 modalities, including cardiac CT, has different sets of use cases, pros & cons. Echocardiography is much more widely available than cardiac CT and can be performed at the patient's bedside.  Watch this excellent video on cardiac CT imaging basics with anatomy explained:   Transthoracic echo is performed with the ultrasound probe on the patient's skin surface, while transesophageal echo is performed with the ultrasound probe within the esophageal lumen. Transesophageal echo offers better image quality that transthoracic echo, though is associated with the risks that come with imaging a patient with an esophageal ultrasound probe, namely the risks associated with sedation, aspiration, and esophageal perforation. Cardiac echo can provide us with structural information about the heart... things like identifying if there's a mass or thrombus in a cardiac chamber, the size and wall thickne...