ECG PEARL: VERAPAMIL-SENSITIVE FASCICULAR VT Not every ventricular tachycardia has a very wide QRS. Classic clues: 1. RBBB-like morphology: ventricular activation produces a right bundle branch block pattern. 2. Superior axis: suggests a circuit involving the left posterior fascicle. 3. Relatively narrow QRS: often around 120-150 ms, narrower than many other forms of VT. 4. Typical patient: a younger adult, often male, with no apparent structural heart disease. 5. Clinical presentation: episodes may be sustained, exercise-triggered and relatively well tolerated. Mechanism: Re-entry involving the left ventricular Purkinje system produces this characteristic tachycardia. Management matters: - Verapamil can terminate confirmed fascicular VT. - Catheter ablation is highly effective and is a first-line option for symptomatic idiopathic fascicular VT. - Never assume an undifferentiated wide-complex tachycardia is fascicular VT. If the diagnosis is uncertain, manage it as VT; avoid empiric IV verapamil because it can cause severe hypotension. - Hemodynamic instability requires immediate synchronized cardioversion. Key takeaway: RBBB morphology plus a superior axis in a relatively young patient should raise suspicion for left posterior fascicular VT, but the ECG alone does not confirm the mechanism.

A 32-year-old woman develops fever and shortness of breath 36 hours after appendectomy. What is the most likely interpretation of this CXR? A. Right lower-zone pneumonia B. Right-sided pneumothorax C. Isolated right pleural effusion D. Left lower-lobe collapse E. Pulmonary edema