Severe secondary hyperkalemia and arrhythmia from drug interactions between calcium-channel blocker and voriconazole: a case presentation.

BACKGROUND: Patients with kidney disease may have concurrent hypertension and infection. Dihydropyridine calcium-channel blockers (CCB) are the most popular class of antihypertensive drugs used in clinical settings and can be metabolized by cytochrome P450 isoenzyme 3A4 (CYP3A4). Voriconazole is a commonly used antifungal treatment and a CYP3A4-inhibitor. Insufficient attention to drug interactions from the concomitant use of CCB and voriconazole may result in serious adverse reactions. CASE PRESENTATION: Here, we report a patient with acute kidney injury on stable anti-neutrophil cytoplasm antibody associated vasculitis who developed hyperkalemia resulting in sinus arrest with junctional escape rhythm attributed to drug interactions of CCB with voriconazole. This is a very rarely reported case and may be an under-recognized complication. After continuous renal replacement therapy and changing the anti-hypertensive drugs, symptoms, and laboratory abnormalities of the patient fully recovered. CONCLUSIONS: This case warns us of severe consequences of drug interactions. Co-prescription of CYP3A4-inhibitors with calcium-channel blockers increases the risk of hypotension and acute kidney injury, which may further induce hyperkalemia and arrhythmia.

Chinese Patent medicine to treat a 32-year-old man with sinus bradycardia and cardiac sinus arrests: A case report.

RATIONALE: Sinus bradycardia refers to a sinus heart rate <60 bpm. Cardiac sinus arrests refer to the omission of atrial activation caused by transient cessation of impulse generation at the sinoatrial node. Normally, drugs such as atropine, isoproterenol, dopamine, dobutamine, or epinephrine can be used for the acute treatment of bradycardia. Temporary pacing is used for treating severe symptomatic bradycardia due to a reversible cause. Permanent cardiac pacing is used for chronic therapy of bradycardia. However, for traditional Chinese medicine (TCM), benefiting qi and nourishing yin and activating blood circulation is the general principle in treatment and show remarkable curative effects. PATIENT CONCERNS: A 32-year-old man was found to have 1-degree atrioventricular block and sinus bradycardia during a physical examination. He reported suffering from palpitation and shortness of breath occasionally. An ambulatory electrocardiogram showed sinus arrhythmia, sinus bradycardia, and significant sinus arrhythmia. The minimum heart rate was 33 bpm (beats per minute). The number of sinus arrest was 42 and the maximum RR interval was 2216 ms. DIAGNOSES: The patient was diagnosed with bradyarrhythmia in Western medicine and "palpitation" in TCM. INTERVENTIONS: The patient was treated with methods of benefiting qi and nourishing yin and activating blood circulation along with warming yan for nearly 5 months. CPM (Chinese patent medicine) such as Yixinshu capsule, Bingdouling oral liquid, Zhenyuan capsule, Zhibaidihuang pills were used for treatment. At the same time, he was suggested to change his lifestyles including falling asleep before 10:00 PM and abandoning spicy diets. OUTCOMES: The symptoms of palpitation and shortness of breath disappeared. The minimum heart rate increased from 33 to 42 bpm and sinus arrests did not occur. The maximum RR interval decreased from 2216 to 1650 ms and the remarkable sinus arrhythmia had improved obviously. LESSONS: This case report shows that TCM can be an effective alternative therapy for sinus bradycardia and cardiac sinus arrests. CPM may have been a successful intervention in arrhythmias.

Sinus arrest following angioplasty and stenting for superior vena cava syndrome.

Superior vena cava (SVC) syndrome is a complication resulting from long-term residence of leads or in-dwelling catheters at the SVC to right atrial (RA) junction. SVC syndrome management is complicated by variable responses to anticoagulation therapies and technically challenging interventional procedures, such as balloon dilatation or stent placement at the SVC-RA junction to relieve blood-flow obstruction. Potential complications resulting from angioplasty/stenting for SVC syndrome are serious and include stent migration, major bleeding, and embolism. Bradyarrhythmias have not been reported. We describe a case of balloon angioplasty and stenting for SVC syndrome in a dialysis patient that resulted in sinus arrest. The complication developed within hours of angioplasty/stenting of her chronic, non-thrombotic SVC obstruction. We highlight the management approach to this patient and discuss potential mechanisms underlying the complication.