What does the T wave represent in an electrocardiogram (ECG)?

A 27-year-old man presents to the emergency department after being stabbed in the right side of his chest. He complains of severe chest pain and shortness of breath. His vital signs are: T 37.2°C, HR 120 bpm, RR 30 breaths/min, BP 90/60 mmHg, and SpO₂ 86% on room air. On examination, there is decreased breath sounds and hyperresonance to percussion on the right side. A chest X-ray is performed.

Question: What pulmonary pattern is most likely seen on his chest X-ray?

Calculate the heart rate from this electrocardiogram.

A 62-year-old man with a history of chronic kidney disease presents with increasing shortness of breath and swelling in his legs over the past week. His vital signs are: T 36.8°C, HR 96 bpm, RR 22 breaths/min, BP 150/90 mmHg, and SpO₂ 93% on room air. On physical examination, there are decreased breath sounds and dullness to percussion at both lung bases. A chest X-ray is ordered.

Question: What pulmonary pattern is most likely seen on his chest X-ray?

How is the cardiac axis in the following electrocardiogram?

A 59-year-old man presents with a 3-month history of persistent cough, unintentional weight loss, and occasional streaks of blood in his sputum. He denies fever or recent infections. His vital signs are: T 37.0°C, HR 88 bpm, RR 18 breaths/min, BP 128/82 mmHg, and SpO₂ 95% on room air. On auscultation, breath sounds are decreased over the right upper lung field. A chest X-ray is obtained to investigate the cause of his symptoms.

Question: What pulmonary pattern is most likely seen on his chest X-ray?

If the PR interval on an electrocardiogram is prolonged beyond 0.20 seconds without any other abnormalities, what is this condition called?

A 54-year-old man with a long history of smoking presents with sudden onset of shortness of breath and mild chest discomfort. He denies fever or sputum production. His vital signs are: T 36.9°C, HR 94 bpm, RR 20 breaths/min, BP 126/80 mmHg, and SpO₂ 92% on room air. On physical examination, breath sounds are markedly decreased over the right lung, and there is dullness to percussion. A chest X-ray is ordered to evaluate the cause.

Question: What pulmonary pattern is most likely seen on his chest X-ray?

In an electrocardiogram, how many millivolts does one large square represent?

In which of the following films have director Christopher Nolan and actor Cillian Murphy collaborated?