Dr. Usman's Cardiology Notes

  ECG Interpretation The electrocardiogram (ECG) is a crucial diagnostic tool for assessing the electrical activity of the heart. A thorough understanding of ECG interpretation is essential for identifying various cardiac conditions and guiding clinical decision-making. Normal ECG A normal ECG consists of several key components: - P wave: represents atrial depolarization - PR interval: time between the onset of the P wave and the QRS complex - QRS complex: represents ventricular depolarization - QT interval: time between the onset of the QRS complex and the end of the T wave - T wave: represents ventricular repolarization Heart Rate To calculate the heart rate, count the number of R-R intervals in 6 seconds and multiply by 10. A normal heart rate is between 60-100 beats per minute. Rhythm Assess the rhythm by evaluating the P-P interval and R-R interval. A regular rhythm has a consistent P-P and R-R interval. P Wave Evaluate the P wave for morphology, duration, and axis. Abnormalit...

 Mitral Fibrous Ring Causing Mitral Stenosis Mitral annular calcification (MAC) or mitral fibrous ring can cause mitral stenosis, particularly in elderly patients. The calcification or fibrosis of the mitral annulus can extend to the leaflets, causing restricted mobility and stenosis. Causes - Degenerative changes - Aging - Hypertension - Atherosclerosis - Chronic kidney disease Echo Findings - Mitral annular calcification or fibrosis on 2D echo - Restricted mobility of the mitral leaflets - Reduced mitral valve area - Increased transmitral gradient - Doppler echo can estimate the mitral valve area and gradient Severity Assessment - Mild MAC: small, localized calcification - Moderate MAC: larger calcification with restricted leaflet mobility - Severe MAC: extensive calcification with significant leaflet immobility and stenosis Clinical Implications - Mitral stenosis can lead to symptoms like dyspnea, fatigue, and palpitations - Severe MAC can increase the risk of cardiovascular eve...

 During an electrophysiology (EP) study for typical AVNRT (Atrioventricular Nodal Reentrant Tachycardia), a VAV (Ventriculo-Atrial-Ventricular) response can be a crucial diagnostic finding. What is a VAV response? A VAV response occurs when a ventricular extrastimulus (a premature ventricular beat) is introduced during the tachycardia. This extrastimulus conducts retrogradely (backward) to the atrium, causing atrial activation (A). Subsequently, the atrium activates the ventricle again through the AV node, resulting in another ventricular activation (V). Why is the VAV response important in AVNRT? The VAV response helps diagnose AVNRT and differentiate it from other supraventricular tachycardias. In AVNRT, the VAV response typically demonstrates: 1. Retrograde conduction: The ventricular extrastimulus conducts backward to the atrium, indicating the presence of a retrograde pathway (usually the fast pathway). 2. Anterograde conduction: The subsequent atrial activation conducts down ...

    Infection Prevention & Control Assessment   Total MCQs = 30   Key is given at the end.   1.   What is the primary objective of environmental cleaning in healthcare settings according to WHO?         A. To maintain a pleasant smell in patient areas          B. To meet hospital accreditation standards         C. To remove dirt and reduce the presence of microorganisms         D. To reduce laundry workload   2.   Which of the following surfaces requires the most frequent cleaning?         A. Walls         B. Bed rails         C. Ceilings         D. Windows   3.   According to WHO guidelines, how often should high-touch surfa...

  So the QRS !!!!!  A few have posed me this question about the true value of QRS , its morphological presentations ,especially the clues in it , for the identification of the various types of abnormalities especially the tachycardias based on these QRS features .  But To understand the abnormalities , one must be able to understand the normalities & especially the slight aberrations associated with the other wise normalities !  The QRS is usually a very well-defined electrical signal on surface ecg and is indicative of underlying ventricular depolarisation phase( since a large mass of muscle is activated almost synchronously hence the larger deflections & this time interval coincides with repolriazation of atrium, hence the latter repolriazation is masked in the QRS complex) . The QRS usually lasts about 100 msec or even less (on average May be of 60 msec to 80 msec duration) ! Generally a duration longer than 120 msec is considered longer! The even more ...

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 ...

✔Bidirectional VT The tachycardia with an identity crisis. What you'll see: Beat-to-beat alternation in QRS axis (often ~180) RBBB-like morphology, most visible in lead Il or aVF Regular rhythm, but clearly not your standard VT Why it most likely happens: Triggered activity (delayed afterdepolarizations) Classically: two competing ventricular foci or alternating fascicular exits Top causes: Digoxin toxicity (check that level!) CPVT (stress-induced VT in the young) Andersen-Tawil syndrome Rare: aconite poisoning, myocarditis Key point:  BiVT is rare - but when you see it, it narrows the differential dramatically.