Heart Block

A middle-aged female arrived at the emergency department with an inferior wall ST-elevation myocardial infarction (STEMI) and received thrombolysis with streptokinase. She initially improved after 1 hour but later developed hypotension, with a blood pressure of 80/50 mmHg, and her heart rate fluctuated between 35 and 45. An urgent ECG revealed a third-degree atrioventricular (AV) block. What is the most suitable course of action?

A 50-year-old male arrived at the emergency department with abrupt, intense central chest pain, accompanied by diaphoresis and vomiting. The ECG confirmed an anterior wall myocardial infarction (MI) with ST elevation in leads V1, V2, V3, and V4. During examination, he displayed a pulse rate of 35/min, irregular rhythm, and a blood pressure of 85/55 mmHg, along with bilateral basal crepitations and an elevated jugular venous pressure (JVP). Intravenous atropine was administered twice, and an ECG was conducted, confirming third-degree heart block. Despite atropine use, his heart rate remained unchanged. What is the most appropriate next crucial step?

In the emergency department, a middle-aged man reported a history of three episodes of syncope within the past two months. He couldn’t recall any warning signs preceding the syncope, but according to the attendant, he became markedly pale, followed by a flushing episode. Stokes-Adams attack was suspected. What is the most prevalent cause of this condition?

A 68-year-old retired school teacher presents to the cardiology outpatient clinic with recurrent episodes of dizziness and near-syncope over the past two weeks. She suffered an inferior wall myocardial infarction four weeks ago that was successfully thrombolyzed in a tertiary care hospital. She was discharged on dual antiplatelet therapy, statin, and beta-blocker.

Since discharge, she reports experiencing sudden palpitations followed by lightheadedness twice daily. There is no history of chest pain, orthopnea, or leg swelling.

On examination:

• Blood pressure: 128/72 mmHg
• Pulse: 70/min, regular
• JVP: not raised
• Heart sounds: normal, no murmurs
• Lungs: clear

Investigations:

• FBC & renal function: within normal limits
• Serum potassium: 4.2 mg/dL
• Serum calcium: 9.4 mg/dL
• Chest X-ray: normal
• ECG: Sinus rhythm with Q waves in leads II, III, aVF; PR interval prolonged
• Echocardiogram: normal left ventricular function, no structural abnormality
• 24-hour Holter monitoring: two episodes of bradycardia with a ventricular rate of 30/min; P waves noted to be dissociated from QRS complexes. Both episodes correlated with her symptoms.

What is the most appropriate management for this patient?

A 55-year-old male is referred to the cardiology clinic after his company’s annual health screening revealed an abnormal ECG. He is a non-smoker, does not drink alcohol, and exercises regularly by playing badminton four times a week. He denies chest pain, dyspnea, syncope, or palpitations. His medical history is unremarkable, and he takes no medications.

On examination:

• Blood pressure: 122/80 mmHg
• Pulse: 54 beats/min, regular
• Jugular venous pressure: not raised
• Cardiovascular and respiratory systems: normal

Investigations:

• ECG: Sinus rhythm with second-degree AV block, Mobitz type I (Wenckebach)
• Chest X-ray: normal
• Full blood count: normal
• Serum electrolytes: Na⁺ 139 mEq/L, K⁺ 4.1 mEq/L (4.1 mmol/L = 16 mg/dL), Ca²⁺ 9.5 mg/dL
• Renal and liver function tests: normal
• Lipid profile: total cholesterol 176 mg/dL, LDL 102 mg/dL, HDL 48 mg/dL, triglycerides 138 mg/dL

What is the most appropriate management for this patient?