Dr. Usman's Cardiology Notes

 Systolic Flow Reversal in Severe Tricuspid Regurgitation: An Important Doppler Sign Tricuspid regurgitation (TR) is increasingly recognized as an important determinant of symptoms, right-sided heart failure, hospitalization, and prognosis. Echocardiography remains the primary imaging modality for evaluating TR. Among the supportive Doppler findings of severe TR, systolic flow reversal in the hepatic veins is particularly useful. Current echocardiographic recommendations include hepatic vein systolic flow reversal among the important signs supporting severe TR. --- What Is Normal Hepatic Vein Flow? Hepatic venous flow can be assessed using pulsed-wave (PW) Doppler, usually from the subcostal window. A normal hepatic venous Doppler tracing contains: S wave: Forward flow toward the right atrium during ventricular systole. D wave: Forward flow during early ventricular diastole. A reversal wave: Brief retrograde flow during right atrial contraction. Normally, forward systolic flow is p...

Noninfarction Q Waves on ECG: Differential Diagnosis and Clinical Approach Q waves on an electrocardiogram (ECG) are often associated with previous myocardial infarction (MI). However, an important clinical principle is: Not every Q wave represents myocardial infarction. Q waves can occur as normal variants or as a result of changes in cardiac position, ventricular hypertrophy, cardiomyopathy, myocardial infiltration, and conduction abnormalities. Recognizing these noninfarction Q waves is important because an incorrect diagnosis of previous MI may lead to unnecessary investigations, anxiety, and inappropriate treatment. This article provides a practical differential diagnosis of Q waves that may occur without myocardial infarction. --- What Is a Q Wave? A Q wave is the first negative deflection of the QRS complex occurring before the first positive deflection (R wave). Small Q waves can be entirely physiological because normal ventricular depolarization begins in the interventricular ...

Parameters of Right Ventricular Dysfunction on Echocardiography in Acute Pulmonary Embolism Acute pulmonary embolism (PE) can produce a sudden increase in pulmonary vascular resistance, resulting in acute right ventricular (RV) pressure overload, RV dilatation, impaired RV contractility, and eventually hemodynamic collapse. Echocardiography therefore plays an important role in identifying RV dysfunction, assessing the hemodynamic consequences of acute PE, and supporting risk stratification. Importantly, echocardiographic abnormalities should be interpreted in the overall clinical context because no single echocardiographic finding is sufficiently sensitive or specific to establish or exclude acute PE in most patients. --- Why Does the Right Ventricle Fail in Acute Pulmonary Embolism? When a significant portion of the pulmonary arterial circulation becomes obstructed, pulmonary vascular resistance rises abruptly. The thin-walled right ventricle is poorly adapted to a sudden increase in ...

  Oral Antiplatelet Dosing in ACS — High-Yield Guide Acute coronary syndrome (ACS) includes STEMI, NSTEMI, and unstable angina. Antiplatelet therapy is a cornerstone of treatment because platelet activation and aggregation play a central role in coronary thrombus formation. In most patients with ACS, treatment involves dual antiplatelet therapy (DAPT): Aspirin + a P2Y12 receptor inhibitor The commonly used oral P2Y12 inhibitors are clopidogrel, prasugrel, and ticagrelor. --- 1. Aspirin Aspirin irreversibly inhibits cyclooxygenase-1 (COX-1), reducing thromboxane A₂ production and platelet aggregation. Loading Dose 162–325 mg orally Chewable, non-enteric-coated aspirin is preferred when rapid platelet inhibition is required. Maintenance Dose 75–100 mg once daily A commonly used maintenance dose is 81 mg/day. High-Yield Point Aspirin should generally be given as early as possible in ACS unless there is a true contraindication, such as significant active bleeding or serious aspirin hyp...

Newly Approved Cardiology Drugs (2022–2026): The New Era of Precision Cardiovascular Medicine The field of cardiovascular medicine is undergoing one of its most exciting transformations in decades. Rather than relying solely on traditional therapies, clinicians now have access to highly targeted drugs that address the underlying mechanisms of disease. Between 2022 and 2026, several breakthrough medications have either gained regulatory approval or reached major milestones, offering new hope for patients with hypertrophic cardiomyopathy, dyslipidemia, hypertriglyceridemia, resistant hypertension, obesity, and arrhythmias. This article reviews these landmark therapies, their mechanisms of action, clinical indications, key trials, and future role in cardiovascular practice. --- Timeline of Recent Cardiovascular Drug Innovations • 2022 – Mavacamten • 2023 – Aficamten • 2024 – Semaglutide (Cardiovascular Risk Reduction) • 2025 – Etripamil • 2025 – Lerodalcibep • 2025 – Plozasiran • 2026 – O...

Have a look on his example fluoroscopy screen of Philips cath lab/fluoroscopy monitor during coronary angiography (CAG). Here's what the displayed parameters mean: Display Meaning CAG 15 f/s Coronary angiography at 15 frames/second (cine acquisition). Higher frame rate = smoother motion but higher radiation. LAO/RAO: 0° No Left Anterior Oblique or Right Anterior Oblique angulation. Straight AP view. CRA/CAU: 0° No cranial or caudal tilt. AP projection. SID: 95 cm Source-to-Image Distance = distance from X-ray tube focal spot to detector. 8" Field of view (FOV) is 8 inches. Smaller FOV provides magnification and better spatial resolution. 0° (rotation icon) Detector rotation is neutral. 89 cm Table height (approximately detector/patient positioning parameter). 38 cm Detector position or source-to-patient distance parameter (machine dependent). 1° Slight detector/head tilt. 0% Image processing/roadmap or contrast enhancement parameter (vendor-specific). Eye icon + L LIH (Last Im...

  Mavacamten: Mechanism of Action, Indications, Dosing, Monitoring, and Clinical Evidence in Obstructive Hypertrophic Cardiomyopathy (HCM) Introduction Hypertrophic cardiomyopathy (HCM) is the most common inherited cardiomyopathy, affecting approximately 1 in 500 individuals. In many patients, excessive myocardial contractility causes dynamic left ventricular outflow tract (LVOT) obstruction, leading to exertional dyspnea, chest pain, dizziness, syncope, and reduced exercise capacity. For decades, treatment consisted mainly of beta-blockers, non-dihydropyridine calcium channel blockers, disopyramide, and septal reduction therapy. The introduction of Mavacamten represents a major breakthrough because it is the first disease-specific medication that directly targets the underlying pathophysiology of obstructive HCM rather than simply relieving symptoms. Approved by the FDA in 2022 and recommended in contemporary ACC/AHA and ESC guidelines, Mavacamten has transformed the management of...