A Coffee Drinker With Sudden-Onset Dyspnea, Tachycardia

Lemi Luu, MD


April 28, 2022


The ECG shows an irregularly irregular heart rhythm with no discernible P waves. Rapid atrial fibrillation (AF) may be hard to differentiate from a narrow supraventricular tachycardia (SVT) without close examination of an ECG. The two conditions can result in similar symptoms of heart palpitations and shortness of breath. Patients with rapid AF are not uncommonly given adenosine to treat presumed SVT, as in this case. Although this treatment is typically unsuccessful, the underlying atrial rhythm may be accurately determined when the heart rate briefly slows.

The conversion from a normal sinus rhythm to AF may be due to numerous conditions, including hyperthyroidism, anemia, infection, ischemic heart disease, valvular disease, drug intoxication, or use of stimulants. Increased stress, overconsumption of coffee, and smoking are possible instigating factors in this patient.

AF is a common arrhythmia characterized by chaotic atrial depolarizations without effective mechanical atrial contractions. This rhythm is often seen with increasing age, with a male predominance. This arrhythmia can result in decreased cardiac output and the formation of atrial thrombi. Many patients with AF are asymptomatic, and most have recurrent episodes without knowledge of them.

The American College of Cardiology established a classification system for AF that is based on its duration and etiology. The categories are paroxysmal AF, persistent AF, permanent AF, and lone AF.

In paroxysmal AF, the episodes last less than 1 week. If they recur, the condition is considered recurrent paroxysmal AF.

In persistent AF, the episodes last longer than 1 week. In long-standing persistent AF, the episode lasts longer than 1 year. In permanent AF, the episode is long-standing, and no further efforts are made to restore sinus rhythm.

Finally, in lone AF, no underlying structural cardiac or pulmonary disease is found. Patients with lone AF have a low risk for death and thromboembolism and may have paroxysmal, persistent, or permanent AF.


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