ECG From Scratch #29: Axis Deviation in Seconds You don't always need to calculate the exact QRS axis. For beginners, start with one simple question: (Is the QRS axis normal, leftward, or rightward?) ➡️ You can often answer this by looking at just Lead I and Lead II. The quick method Look at the overall QRS polarity in I and II. 1️⃣ Lead I positive + Lead II positive = Normal axis 2️⃣ Lead I positive + Lead II negativ: Left axis deviation (LAD) 3️⃣ Lead I negative + Lead II positive: Right axis deviation (RAD) 4️⃣ Lead I negative + Lead II negative: Extreme axis deviation Also called an indeterminate or northwest axis in some ECG terminology. This isn't a substitute for precise axis calculation when needed, but it is an excellent first-pass screening method. And remember: Axis interpretation starts with polarity, not mathematics. 📸 Courtesy of: litfl.com/cardiac-axis-train…

All but ONE of the following conditions may cause right axis deviation: A. Reversal of the LA and RA electrodes B. Severe COPD C. Lateral wall MI D. Acute or chronic PE E. Left anterior fascicular block

Echo From Scratch | Post #19 What Else Can You See in the Parasternal Long-Axis View? The PLAX view is not only about the aortic and mitral valves. Look carefully, and you can assess the left atrium, left ventricle, interventricular septum, posterior wall, right ventricular outflow tract, descending aorta, coronary sinus, and even the space between the heart and descending aorta. 1. The left atrium The left atrium lies posterior to the aortic root. In a normal adult, its anteroposterior dimension is roughly similar to the dimension of the aortic sinuses. The right pulmonary artery passes between the proximal ascending aorta and the superior aspect of the left atrium, although it is often difficult to visualize clearly on adult TTE. 2. The coronary sinus The coronary sinus lies in the atrioventricular groove, posterior to the mitral annulus. A markedly dilated coronary sinus should make you think about a persistent left superior vena cava. If necessary, this can be investigated with agitated-saline contrast injected into a left arm vein. A persistent left SVC is often an incidental finding, but it can also occur with congenital heart disease. 3. Look behind the left atrium Posterior to the LA, the descending thoracic aorta can be seen in cross-section. With appropriate transducer rotation, the descending aorta can also be imaged in long axis. This relationship is clinically useful when evaluating fluid around the heart. The oblique pericardial sinus lies between the LA and descending aorta. Therefore: 🟥 Pericardial effusion can appear between the LA and descending aorta. 🟦 Pleural effusion is located posterior to the descending aorta. The ASE comprehensive TTE guideline specifically recommends increasing imaging depth beyond the posterior LV wall from the PLAX view to assess for abnormalities such as pericardial or pleural effusions. 4. The LV myocardium The PLAX view gives an excellent look at the basal and mid-ventricular interventricular septum and posterior wall. This allows assessment of: *️⃣ Wall thickness *️⃣ LV internal dimensions *️⃣ Endocardial motion *️⃣ Myocardial thickening However, an important limitation: The LV apex is not visualized from the standard parasternal long-axis view. What may appear to be the apex is often an oblique section through the anterolateral LV wall. This is one reason why LV assessment should never rely on a single imaging plane. 5. And then there is the RV The right ventricle is fundamentally different from the LV. The LV has a relatively symmetric ellipsoid geometry with recognizable long and short axes. The RV does not. Instead, the RV wraps around the LV and can be thought of as having three regions: 🔸Inflow region 🔸Apical region 🔸Outflow region This produces a somewhat crescentic or U-shaped chamber around the LV. Because standard 2D planes often cut the RV obliquely, RV size and systolic function should be assessed using multiple views. Three-dimensional imaging can provide additional information when appropriate.

Why is the right kidney normally positioned slightly lower than the left?

Amiodarone-induced thyrotoxicosis: Type 1 vs Type 2 Two mechanisms. Two different treatments. 🟥 Type 1 AIT Iodine-induced increased thyroid hormone synthesis, usually in patients with underlying thyroid disease such as multinodular goiter or latent Graves’ disease. Treatment: Thionamide therapy such as carbimazole/methimazole. Potassium perchlorate may be considered in selected settings. 🟦 Type 2 AIT Destructive thyroiditis caused by amiodarone, usually occurring in a previously normal thyroid. Treatment: Glucocorticoids, typically prednisone/prednisolone. The catch: Goiter alone does not reliably distinguish the two. Mixed or indeterminate AIT occurs and may require both a thionamide and glucocorticoid. Amiodarone withdrawal should be an individualized cardiology-endocrinology decision, particularly when it is essential for controlling a serious arrhythmia. #CardioTwitter

A young man presents to the emergency department with altered mental status and profound hypothermia. Look closely at the precordial leads. Which ECG finding is most characteristic of this presentation? A. Delta waves B. Osborn waves C. Epsilon waves D. U waves

MINOCA is not a diagnosis. It is a working diagnosis. The 2023 ESC ACS Guidelines define MINOCA as acute MI with <50% stenosis in the major epicardial coronary arteries, requiring further investigation to identify the underlying cause. Possible mechanisms include: 1️⃣ Plaque rupture or erosion 2️⃣ Coronary spasm 3️⃣ Coronary embolism/thrombosis 4️⃣ SCAD 5️⃣ Coronary microvascular dysfunction 6️⃣ Myocardial bridging 7️⃣ Type 2 MI from supply-demand imbalance Important mimics include myocarditis and Takotsubo syndrome. The key is to identify the mechanism, because treatment depends on the final diagnosis. MINOCA is the starting point of the diagnostic work-up, not the endpoint.

Echo From Scratch | Post #18 Mitral Valve Anatomy: More Than Just Two Leaflets The mitral valve is not simply a two-leaflet structure. The complete mitral valve apparatus consists of: ⚪Anterior and posterior leaflets ⚫ Mitral annulus 🔴 Chordae tendineae 🔵 Papillary muscles Understanding how these structures work together is essential for interpreting mitral stenosis, mitral regurgitation, prolapse, and systolic anterior motion. 1️⃣ Anterior vs posterior leaflet The anterior mitral leaflet is longer than the posterior leaflet, but it attaches to a smaller portion of the mitral annular circumference. The posterior leaflet has a shorter length but a larger annular attachment. The posterior leaflet is conventionally divided into three scallops: P1: lateral P2: central P3: medial The anterior leaflet is commonly described as A1, A2, and A3, corresponding to the lateral, central, and medial regions. This segmental terminology becomes particularly important when describing the location of mitral valve pathology. What happens during diastole? As the mitral valve opens, the leaflets separate. The anterior leaflet moves toward the interventricular septum and normally approaches or contacts it during diastole. The chordae and papillary muscles provide the subvalvular support that guides leaflet motion. What happens during systole? During systole, the two leaflets come together and form a zone of coaptation. Normally, the chordae remain posterior to the plane of leaflet coaptation. This is important because abnormal anterior motion of the mitral apparatus can contribute to LV outflow tract obstruction. Chordal SAM vs leaflet SAM Not every systolic anterior movement of the mitral apparatus means hypertrophic cardiomyopathy. Some individuals have mild redundancy of the chordae, producing chordal systolic anterior motion without significant hemodynamic obstruction. This is different from the pathological systolic anterior motion of the mitral leaflets that can occur in hypertrophic cardiomyopathy and contribute to LV outflow tract obstruction and mitral regurgitation. Modern HCM imaging recommendations emphasize echocardiography for assessing these mechanisms. 2️⃣ The mitral annulus The mitral annulus is a three-dimensional fibrous structure rather than a simple flat ring. It has an elliptical, saddle-like configuration. Its geometry also explains why different echocardiographic views intersect different portions of the annulus: The four-chamber view cuts through the more apical major axis. The parasternal long-axis view cuts through the more basal minor axis. So the mitral annulus can look very different depending on the imaging plane. High-yield takeaway: The anterior leaflet is longer but has a smaller annular attachment. The posterior leaflet has three scallops: P1, P2, and P3. Both leaflets are supported by chordae and papillary muscles, forming one functional mitral valve apparatus.

Know Your Mitral Valve Before you can understand mitral valve repair, you need to know how the valve is divided. The classic Carpentier classification divides the mitral valve into six segments: Anterior leaflet A1: anterolateral A2: middle A3: posteromedial Posterior leaflet P1: anterolateral P2: middle P3: posteromedial The posterior leaflet naturally has two indentations, creating three scallops: P1, P2 and P3. The anterior leaflet usually has no obvious indentations, so its segments are named according to the posterior leaflet they oppose: A1 ↔ P1 A2 ↔ P2 A3 ↔ P3 At the ends are the anterolateral and posteromedial commissures, where the anterior and posterior leaflets meet. Why does this matter? Because when an echo report says P2 prolapse or A2-P2 coaptation, the operator immediately knows which part of the valve is involved. This becomes especially important during mitral transcatheter edge-to-edge repair (M-TEER), where precise identification of leaflet segments is essential for planning and guiding the procedure. Modern 2D and 3D TEE are central to this process. Simple way to remember it: A1/P1 = lateral A2/P2 = middle A3/P3 = medial Master the segments, and mitral valve imaging becomes much easier to understand. Source: Braunwald's Heart Disease, 12th ed.

A patient presents with palpitations and dyspnea. What rhythm is demonstrated on this ECG?

A patient presents with suspected unstable angina. Which conditions should be considered in the differential diagnosis of acute chest pain? A. Aortic dissection B. Acute pericarditis C. Pneumothorax D. Pulmonary embolism E. None of the above F. All of the above

What congenital condition could explain this unusual finding?

Echo From Scratch | Post #17 Aortic Valve Anatomy in the Parasternal Long-Axis View The parasternal long-axis view gives you much more than a picture of the aortic valve. It allows you to understand the relationship between the aortic valve, aortic root, interventricular septum, mitral valve, and left atrium. Know the aortic cusps In the standard PLAX view: 1️⃣ Right coronary cusp (RCC) is anterior. 2️⃣ Noncoronary cusp (NCC) is posterior. 3️⃣ Left coronary cusp (LCC) lies largely outside the PLAX imaging plane. During systole, the thin aortic cusps open widely and become nearly parallel to the aortic wall. During diastole, they close centrally. In a normal young valve, the cusps may be so thin that only their coaptation line is clearly visible. Why do the closed cusps look linear? This is an important anatomical concept. The aortic cusps have a curved, hemicylindrical configuration. When viewed in the PLAX plane, their three-dimensional curvature can make the closed leaflets appear almost linear from the coaptation line toward the annulus. So what looks like a simple straight line on 2D echo is actually part of a complex three-dimensional structure. The crown-shaped aortic annulus The attachment of the three aortic cusps has a characteristic crown-like configuration. The commissures are located near the upper portions of the sinuses of Valsalva, while the central portions of the cusps attach lower down. Each cusp also has a coaptation zone where adjacent leaflets meet. A thicker central portion, the nodule of Arantius, is found on each cusp. Understanding this 3D anatomy helps when assessing: - Aortic stenosis - Aortic regurgitation - Aortic valve morphology - Aortic root disease - Congenital aortic valve abnormalities The aortic-mitral relationship One of the most important landmarks in PLAX is the fibrous continuity between the aortic root and the anterior mitral leaflet. There is no intervening myocardium between these structures. This aortic-mitral continuity is particularly useful when identifying the anatomical left ventricle in patients with complex congenital cardiac anatomy. A good PLAX view turns 2D anatomy into a mental 3D model. Current ASE guidance also emphasizes standardized terminology and reporting of aortic valve and aortic root findings, while modern multimodality assessment recognizes that 2D TTE may not fully capture the maximum three-dimensional aortic root anatomy. #Cardiology #AorticValve

Cardiac Auscultation: Know the 5 Classic Areas Where you listen matters. Each area is positioned to best hear sounds associated with a particular cardiac valve or region. 1. Aortic: 2nd intercostal space, right sternal border 2. Pulmonic: 2nd intercostal space, left sternal border 3. Accessory aortic: 3rd intercostal space, left sternal border 4. Tricuspid: 5th intercostal space, left sternal border 5. Mitral: Cardiac apex, typically at the 5th intercostal space near the midclavicular line A useful clinical point: these are areas of maximal auscultation, not the exact anatomical locations of the valves. Knowing these landmarks helps localize murmurs and other abnormal heart sounds during the cardiovascular examination.