Nicorandil as a promising therapeutic option for ventricular arrhythmia: A case report and review of literature

Abstract

Background: Ventricular arrhythmia is a common type of arrhythmia observed in clinical practice. It is primarily characterized by premature ventricular contractions, ventricular tachycardia, and ventricular fibrillation. Abnormal formation or transmission of cardiac electrical impulses in patients affects cardiac ejection function. It may present with symptoms such as palpitations, dyspnea, chest discomfort, and reduced exercise tolerance. In severe cases, ventricular arrhythmia can even lead to death. Therefore, prompt treatment is very much essential upon diagnosis. The symptoms did not improve after previous conventional drugs and electrical defibrillation treatment, but the ventricular arrhythmia was prevented after the addition of nicorandil.

Case summary: A 75-year-old female patient was admitted to the hospital because of intermittent chest tightness, shortness of breath for 10 days, and fainting once for 7 days. Combined with laboratory tests and auxiliary examination, the patient was tentatively diagnosed with coronary heart disease or arrhythmia-atrial fibrillation. After admission, the patient had intermittent ventricular arrhythmia, which was uncontrolled with lidocaine, defibrillation, and amiodarone. However, when she was treated with nicorandil, the ventricular arrhythmia stopped. Nicorandil mitigates the action potential duration by facilitating the opening of potassium ion channels, thereby regulating the likelihood of premature and delayed depolarization in two distinct phases and subsequently averting the onset of malignant ventricular arrhythmia. Nicorandil may inhibit ventricular arrhythmia by dilating coronary arteries, improving coronary microcirculation and reducing myocardial fibrosis.

Conclusion: Nicorandil is a drug with dual effects. It could be used as a new therapeutic option for inhibiting ventricular arrhythmias.

Keywords: Amiodarone; Case report; Electrical storm; Lidocaine; Microcirculation; Myocardial fibrosis; Nicorandil; Phase 2 early after-depolarization; Ventricular arrhythmia.

Figure 1

Patient outcomes. A: The heart rhythm of patient developed short array ventricular tachycardia and ventricular fibrillation after atrial fibrillation; B: Atrial fibrillation, with a heart rate of 166 beats/minute, QTc 493 ms; C: Sinus rhythm, with a heart rate of 47 beats/minute, QTc 539 ms; D: Heart rhythm of patient was atrial fibrillation; E: Heart rhythm was converted to sinus rhythm with rate 49 beats/minute, QTc 433 ms.