Dr. Usman's Cardiology Notes

Normal ECG Changes During Pregnancy Pregnancy induces profound physiological changes in the cardiovascular system to meet the increased metabolic demands of the mother and fetus. These changes are reflected on the electrocardiogram (ECG) and are considered normal variants rather than pathological findings. Understanding these expected ECG changes is essential to avoid unnecessary investigations and misdiagnosis. Sinus Tachycardia An increase in resting heart rate is one of the most common ECG changes during pregnancy. Plasma volume expansion, increased cardiac output, and heightened sympathetic tone lead to sinus tachycardia. Heart rate may increase by 10–20 beats per minute, especially in the second and third trimesters, while maintaining normal P-wave morphology and sinus rhythm. Short PR Interval Pregnancy is associated with enhanced atrioventricular (AV) nodal conduction due to increased sympathetic activity. This may result in a mildly shortened PR interval on ECG. Importantly, th...

  Indications of Primary PCI in STEMI Patients (2025 ACC/AHA Guideline) Primary percutaneous coronary intervention (PCI) remains the preferred reperfusion strategy for patients presenting with ST-elevation myocardial infarction (STEMI), provided it can be performed in a timely and appropriate setting. The 2025 ACC/AHA guidelines classify indications for primary PCI based on symptom duration, hemodynamic status, and ongoing ischemic risk. Understanding these classes helps clinicians make rapid, evidence-based decisions in acute coronary care. CLASS I INDICATIONS (Procedure Recommended) Primary PCI is strongly recommended when clear benefit outweighs risk. STEMI with symptom onset less than 12 hours Patients presenting within 12 hours of symptom onset derive the greatest mortality and morbidity benefit from immediate reperfusion. Primary PCI should be performed as soon as possible, ideally within guideline-recommended door-to-balloon times. Acute coronary syndrome with cardiogenic sh...

  IMPORTANT CLINICAL TRIADS: CUSHING’S, BECK’S, AND VIRCHOW’S A practical, bedside-oriented guide for doctors and medical students CUSHING’S TRIAD (Sign of raised intracranial pressure) Cushing’s triad represents a late and ominous physiological response to increased intracranial pressure (ICP). It reflects brainstem compression and impending herniation and should always be treated as a neurological emergency. Components 1. Increased systolic blood pressure (widened pulse pressure) 2. Bradycardia 3. Irregular or decreased respiratory rate Pathophysiology When ICP rises, cerebral perfusion pressure (CPP = MAP − ICP) falls. To maintain cerebral blood flow, the body activates a sympathetic response causing systemic vasoconstriction and increased systolic blood pressure. The elevated blood pressure stimulates baroreceptors, leading to a reflex vagal response and bradycardia. As ICP continues to rise, compression of the medullary respiratory centers results in abnormal, irregular, or sl...

  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 ...

  Roles of a Cardiologist A cardiologist is a physician specialized in the diagnosis, treatment, and prevention of diseases of the heart and blood vessels. Their role spans outpatient care, hospital-based management, advanced procedures, and long-term cardiovascular prevention. Clinical Evaluation and Diagnosis Cardiologists assess patients with symptoms such as chest pain, dyspnea, palpitations, syncope, and edema. A detailed history, physical examination, and risk factor assessment form the foundation of diagnosis. They interpret investigations including ECG, echocardiography, stress testing, ambulatory rhythm monitoring, cardiac CT, and cardiac MRI to accurately identify cardiovascular disease. Management of Ischemic Heart Disease Cardiologists diagnose and manage stable angina, acute coronary syndromes, and myocardial infarction. Responsibilities include risk stratification, optimization of medical therapy (antiplatelets, statins, beta-blockers, ACE inhibitors), and deciding on...

Exercise Tolerance Test (ETT) which is also known as Cardiac Stress Test is now available at SARF Hospital F10 Markaz Islamabad. It is a very important test in screening of obstructed coronary arteries. It is recommended for people with risk factors like smoking, diabetes, hypertension or having symptoms suggestive of underlying cardiac disease. These symptoms may include chest pain on exertion, shortness of breath, palpitations or fatigue. Cardiologist at SARF Hospital will evaluate you before proceeding for the stress test. Feel free to contact at 03135339589 for more information and appointments. Watch introductory video of SARF Hospital below: