Dr. Usman's Cardiology Notes

 

The most dangerous ECGs don’t always have the biggest ST elevation. If you’re staring at V2–V3 trying to decide between Early Repolarization and a subtle LAD occlusion, stop looking at the ST segment and look at the Terminal QRS. What is Terminal QRS Distortion? It’s a binary finding. In V2 or V3, ask yourself: Is the S-wave gone? Is the J-wave gone? If the answer to both is YES, you are looking at Grade III ischemia. The Stats: Specificity: ~100% vs. Early Repolarization. BER simply doesn’t do this. Sensitivity: ~20–35%. It won’t catch every STEMI, but when it’s there, it’s a “rule-in” sign. Risk: Associated with larger infarct size (CMR-proven) and higher rates of heart failure. The Logic: This is depolarization failing in real-time. Severe ischemia slows conduction so much that the end of the QRS gets “swallowed” by the repolarization phase. Takeaway: Millimeters can lie. Morphology rarely does. If the S-wave is missing in the anterior leads, call the lab.

Assessment of Pulmonary Embolism (PE) Pulmonary embolism (PE) is a potentially life-threatening condition requiring rapid, structured, and guideline-directed evaluation. Early risk stratification determines urgency of imaging, need for thrombolysis, and level of care. This post summarizes a practical, ESC-aligned approach to assessment of PE. 1. Clinical Suspicion Always think of PE in patients with: Acute unexplained dyspnea Pleuritic chest pain Hemoptysis Syncope Unexplained tachycardia New hypoxia Risk Factors Recent surgery or immobilization Active cancer Previous VTE Pregnancy/postpartum OCP use Thrombophilia Obesity 2. Hemodynamic Assessment (First Step) Immediately determine if the patient is: A. Hemodynamically Unstable (High-Risk PE) SBP <90 mmHg Drop in SBP ≥40 mmHg Shock or cardiac arrest → Urgent bedside echocardiography → If RV dysfunction present → treat as high-risk PE (consider thrombolysis) 3. Clinical Probability Assessment Use ...

Dyslipidemia Primary Prevention Guidelines (focusing on preventing first cardiovascular events) 1. Cardiovascular Risk Assessment • All adults should have their ASCVD risk estimated using a validated risk calculator (e.g., ACC/AHA pooled cohort risk score, QRISK3, Framingham Risk Score) to guide prevention strategies. Risk factors include age, sex, blood pressure, smoking, diabetes, lipid levels, family history, and others.  • Reassess risk periodically (e.g., every 4–6 years in adults without disease).  2. Lifestyle Modification (First-Line in All Individuals) • Healthy diet: Emphasize vegetables, fruits, whole grains, lean proteins, legumes, nuts; reduce saturated fat, trans fats and dietary cholesterol.  • Physical activity: ≥150 minutes/week of moderate-intensity or ≥75 minutes/week of vigorous aerobic exercise.  • Weight management: Aim for BMI 18.5–24.9 and waist circumference reduction.  • Smoking cessation and blood pressure/glucose control.  3. Lip...

  Pulmonary Vein (PV) Doppler Patterns – Normal and in Disease Pulmonary vein Doppler is recorded using pulsed-wave Doppler (usually from apical 4-chamber view for right upper PV or by TEE). It reflects left atrial (LA) pressure and compliance, and is essential in diastology and mitral valve assessment. ━━━━━━━━━━━━━━━━━━ 1. Normal Pulmonary Vein Doppler Pattern Normal waveform has three components: 1️⃣ S wave (Systolic forward flow) • Occurs during LV systole • Blood flows from pulmonary veins → LA • Normally S ≥ D in younger adults • Reflects LA relaxation and descent of mitral annulus 2️⃣ D wave (Diastolic forward flow) • Occurs during early LV diastole • Corresponds to mitral E wave • Reflects LA pressure and LV relaxation 3️⃣ Ar wave (Atrial reversal) • Occurs during atrial contraction • Small retrograde flow into pulmonary veins • Normally: Ar velocity < 35 cm/s Ar duration < mitral A duration 👉 Normal Pattern: S wave dominant or equal to D Small Ar reversal ━━━━━━━━━━...

  Congenital AV Block – Pacing Indications Congenital atrioventricular (AV) block may be isolated (often immune-mediated due to maternal anti-Ro/SSA or anti-La antibodies) or associated with structural heart disease (e.g., congenitally corrected TGA). Pacing decisions depend on symptoms, ventricular rate, ventricular function, and risk markers. --- 1. Class I Indications (Permanent Pacemaker Recommended) 1. Symptomatic bradycardia Syncope, presyncope Heart failure Exercise intolerance 2. Asymptomatic complete (3rd-degree) AV block with: Wide QRS escape rhythm Ventricular dysfunction Complex ventricular ectopy Prolonged QT interval 3. Neonates/Infants with complete AV block and: Ventricular rate <55 bpm Ventricular rate <70 bpm if associated with congenital heart disease 4. Postoperative advanced AV block Persisting >7–10 days after congenital cardiac surgery --- 2. Class IIa Indications (Reasonable to Pace) 1. Asymptomatic complete AV block beyond infancy with: Average hea...

Vericiguat in Heart Failure: Mechanism, Evidence, Dosing, and Clinical Positiom Introduction Vericiguat is a novel oral soluble guanylate cyclase (sGC) stimulator approved for patients with symptomatic chronic heart failure with reduced ejection fraction (HFrEF) who have had recent worsening heart failure despite guideline-directed medical therapy (GDMT). It targets the nitric oxide–sGC–cyclic GMP pathway, which is impaired in advanced heart failure. This article provides a clinically focused, guideline-oriented review of vericiguat for practicing physicians and cardiology trainees. --- Pathophysiologic Rationale In chronic HFrEF: Endothelial dysfunction reduces nitric oxide (NO) bioavailability Oxidative stress impairs soluble guanylate cyclase activity Reduced cyclic GMP (cGMP) leads to: Increased vascular tone Myocardial stiffness Fibrosis Progressive ventricular remodeling Vericiguat directly stimulates soluble guanylate cyclase and enhances its sensitivity to endogenous NO, restor...