Dr. Usman's Cardiology Notes

  Average LDL-C reduction with lipid-lowering therapies (ESC/EAS): ■ Statins are the foundation: Moderate-intensity ≈ 30% High-intensity ≈ 50% ■ Statin + non-statin combinations markedly improve efficacy: High-intensity statin + ezetimibe ≈ 60% High-intensity statin + bempedoic acid ≈ 58% ■ PCSK9 inhibitors provide the largest incremental effect: PCSK9 mAb alone ≈ 60% With statins ± ezetimibe → 75–80% ■ Maximal LDL-C lowering (~85–86%) is achieved with quadruple therapy (high-intensity statin + ezetimibe + bempedoic acid + PCSK9 mAb). ■ Clinical implication: very-high-risk patients usually require early combination therapy to reach ESC LDL-C targets. #medical #cardiology #hearthealth #heart #fblifestyle

  Bedside Hemodynamic Assessment: An Echocardiography Guide for the ICU Bedside echocardiography has become a cornerstone of modern ICU practice. Beyond simple assessment of left ventricular ejection fraction, focused echocardiography allows real-time evaluation of pressures, congestion, systemic flow, and shock physiology. A structured approach transforms echo from a descriptive tool into a true hemodynamic monitor. --- 1. Role of Echocardiography in ICU Hemodynamics Critically ill patients often have complex, rapidly changing physiology. Invasive monitoring is not always available or reliable. Bedside echocardiography provides: • Non-invasive, repeatable hemodynamic assessment • Immediate correlation with clinical status • Guidance for fluids, inotropes, and vasopressors • Etiologic diagnosis of shock A practical framework divides assessment into two domains: 1. Pressures and congestion 2. Systemic flow and shock state --- 2. Assessing Pressures and Venous Congestion A. Inferior ...

Systolic Anterior Motion (SAM) in Hypertrophic Cardiomyopathy Definition Systolic anterior motion (SAM) refers to anterior displacement of the mitral valve apparatus toward the interventricular septum during systole, leading to dynamic left ventricular outflow tract (LVOT) obstruction and mitral regurgitation. It is a hallmark pathophysiologic feature of hypertrophic cardiomyopathy (HCM), particularly the obstructive phenotype. --- Pathophysiology of SAM SAM is not simply a consequence of septal hypertrophy; it is the result of complex interactions between ventricular geometry, mitral valve anatomy, and flow dynamics. Key mechanisms include: 1. Venturi and Drag Forces High-velocity systolic flow through a narrowed LVOT creates drag forces that pull the anterior mitral leaflet toward the septum. 2. Mitral Valve Abnormalities Elongated anterior mitral leaflet Anterior displacement of papillary muscles Increased leaflet slack These abnormalities predispose the leaflet to systolic displace...

Evolution of ECG Changes in STEMI ST-elevation myocardial infarction (STEMI) produces a characteristic, time-dependent sequence of ECG changes that reflect ongoing myocardial ischemia, injury, and eventual necrosis. Understanding this evolution is critical for early diagnosis, localization of the infarct-related artery, reperfusion decisions, and assessment of infarct age. --- 1. Hyperacute Phase (Minutes to First Hour) Key ECG features Tall, broad-based, symmetrical T waves T wave height disproportionate to QRS complex Often localized to a coronary territory ST segment may still be isoelectric or minimally elevated Pathophysiology Local extracellular potassium accumulation due to acute transmural ischemia Earliest electrical manifestation of coronary occlusion Clinical relevance Easily missed or mistaken for hyperkalemia Recognition allows ultra-early reperfusion before ST elevation becomes obvious --- 2. Acute Injury Phase (Minutes to Hours) Key ECG features ST-segment elevation in c...

 Broken Heart Syndrome (Takotsubo Syndrome, Stress Cardiomyopathy) Definition Broken heart syndrome, also known as Takotsubo syndrome (TTS), is an acute, reversible heart failure syndrome characterized by transient left ventricular systolic dysfunction, usually triggered by intense emotional or physical stress, in the absence of obstructive coronary artery disease sufficient to explain the presentation. Epidemiology Predominantly affects postmenopausal women (≈85–90%) Accounts for 1–3% of patients presenting with suspected acute coronary syndrome (ACS) Increasing recognition due to routine coronary angiography and cardiac MRI Pathophysiology (Guideline-based concepts) Exact mechanism remains multifactorial and incompletely understood. Current ESC and international consensus emphasize: Catecholamine excess Sudden surge in catecholamines leading to myocardial stunning, microvascular dysfunction, and direct myocyte toxicity Coronary microvascular dysfunction Impaired coronary flow res...

MINOCA (Myocardial Infarction with Non-Obstructive Coronary Arteries) Definition: MINOCA is defined as an acute myocardial infarction fulfilling the universal MI criteria, with coronary angiography showing no obstructive coronary artery disease (no stenosis ≥50%) and no alternative non-ischemic explanation at the time of angiography. It is a working diagnosis rather than a final one. Epidemiology • Accounts for ~5–10% of all myocardial infarctions • More common in women and younger patients • Prognosis is not benign and carries a significant risk of recurrent events and mortality Diagnostic Criteria (ESC-based) According to the European Society of Cardiology, all of the following must be present: 1. Clinical evidence of acute myocardial infarction – Ischemic symptoms – ECG changes consistent with MI – Rise and/or fall of cardiac troponin 2. Non-obstructive coronary arteries on angiography (<50% stenosis) 3. No overt alternative diagnosis at presentation (e.g. sepsis, pulmonary embol...

Diastolic dysfunction on echocardiography: a comprehensive, guideline-oriented review Diastolic dysfunction refers to impaired left ventricular (LV) filling due to abnormal relaxation, increased chamber stiffness, or both, leading to elevated LV filling pressures. It is a central mechanism in heart failure with preserved ejection fraction (HFpEF) and contributes significantly to symptoms, prognosis, and management decisions. PHYSIOLOGY OF DIASTOLE LV diastole has four phases: 1. Isovolumic relaxation (IVRT): energy-dependent myocardial relaxation after aortic valve closure 2. Early rapid filling: pressure gradient–driven filling (E wave) 3. Diastasis: minimal flow when LA and LV pressures equalize 4. Atrial contraction: late filling (A wave) Diastolic dysfunction develops when relaxation is delayed, compliance is reduced, or left atrial (LA) pressure rises to compensate. ECHOCARDIOGRAPHIC PARAMETERS FOR DIASTOLIC ASSESSMENT 1. Mitral inflow Doppler Measured in apical 4-chamber view wit...