A 50-year-old man has suddenly developed intense palpitations, pain in the heart, acute weakness, increased blood pressure, and an irregular pulse with pulse deficit. ECG shows f-waves instead of a P wave, R-R intervals are irregular. What heart rhythm disorder is observed in the patient?

• A. Ciliary arrhythmia
• B. Respiratory sinus arrhythmia
• C. Sinus extrasystole
• D. Paroxysmal tachycardia
• E. Transverse heart block