Weathering an adenosine insensitive right ventricular outflow tract ventricular tachycardia (Ado-insensitive RVOT VT) storm in an adolescent female: A case report

INTRODUCTION: Ventricular tachycardias (VT) are commonly associated with structural heart disease. However, 10% of VTs have no identifiable cause. Right ventricular outflow tract ventricular tachycardia (RVOT VT), a small subgroup of idiopathic VTs localized in the right ventricular outflow tract is highly sensitive to adenosine (ADO). Only 11% of RVOT VT is ADO-insensitive, posing a diagnostic challenge. We present a peculiar case of an ADO-insensitive RVOT-VT storm and the challenges of recognizing and managing it in a resource-limited setting. CASE SUMMARY: A 15-year-old female, asthmatic, complained of palpitations, lightheadedness, chest pain and dyspnea a few hours prior to admission. She had a similar episode a month ago, which necessitated ER admission, electrical cardioversion and amiodarone. On admission, she was tachycardic but normotensive. She had diffuse wheezes. Cardiac exam was normal. ECG revealed a wide complex tachycardia (WCT). Work-up revealed a normal chest x-ray, thyroid function tests and electrolytes. Echocardiogram showed a structurally normal heart. She was managed as a case of viral myocarditis and SVT with aberrancy. Vagal maneuvers and adenosine was given which slowed down the tachycardia. She was then started on IV anti-arrhythmics however, sustained symptomatic VT recurred on the same day. ECG analysis showed a WCT, LBBB, AV dissociation with positive QRS complexes in inferior leads suggestive of VT originating from the RVOT. RVOT VT storm was considered and adenosine (maximum dose) was given. The patient did not revert to sinus, hence, ADO-insensitive RVOT VT was considered. Cardioversion terminated the VT storm. On electrophysiology study, the VT was induced/ localized at the RVOT via 3D mapping. Ablation of the RVOT focus was performed, immediately terminating the VT. Post ablation, the patient was asymptomatic and was discharged improved with excellent prognosis. DISCUSSION: This case report highlights two things. The ECG remains a reliable tool in recognizing and localizing VTs clinically. Secondly, it highlights the importance of prompt recognition of ADO-insensitive RVOT VT because its management and prognosis is very different from the common causes of VT.

Adherence to guidelines on anticoagulant management among adult patients with atrial fibrillation at the Philippine General Hospital

BACKGROUND: Atrial fibrillation (AF) is the most common cause of embolic stroke. Although there is impressive risk reduction in stroke associated with warfarin therapy in clinical trials and guidelines on anticoagulation in AF, there are limited data on how well these goals are being met. This study aims to determine the adherence to guidelines on anticoagulant management among adult patients with AF at the Department of Internal Medicine Ward of the University of the Philippines - Philippine General Hospital (UP-PGH).METHODS: This is a prospective study, which included patients aged 18 years and older with diagnosis of AF, which can be paroxysmal, persistent, long-standing or permanent. Upon admission, patients were interviewed and information like age, gender, duration of AF, co-morbid illnesses, and medical history were collected using a checklist. Risk factors for bleeding, use of antiplatelet/anticoagulant agents and International Normalized Ratio (INR) values were also determined.RESULTS: There were 40 subjects included in the study, majority of which were female (77.5%) and in the 40-50 years age range (35%). There were 21 (52.5%) patients who had valvular AF and 19 (47.5%) who had non-valvular AF. Of those patients with valvular AF, 80.9% received warfarin. Of those patients with non-valvular AF, 94.7% were at moderate or high risk for thromboembolism, but only 47.4% of those patients received warfarin. We found that only a small percentage of patients (16%) had INR in the therapeutic range of 2.0-3.0. The majority of the patients had their INR in the sub-therapeutic ranges at 40% and 24% at INR values of 1.5-1.99 and 0-1.49 respectively. The majority of the patients on warfarin had INR monitoring ? 30 days, and these were patients already on chronic or long-term warfarin use. Those patients who had more frequent INR monitoring were those newly initiated on the treatment whose INR values where in the sub-therapeutic range.CONCLUSION: The adherence of anticoagulant management among AF patients admitted at the Internal Medicine Wards of UP-PGH, to evidence-based clinical practice guidelines, was high at 80.9% for patients with valvular AF and was quite low at 47.4% for non-valvular AF patients. Patients were found to have low bleeding risks based on a HAS-BLED score and patients with moderate to high thromboembolic risk factors were more often prescribed with warfarin, although only a few patients achieved a therapeutic INR. A more frequent INR monitoring including a close follow-up with the patients should be performed to achieve target INR in most patients with AF. Moreover, we should not discount starting anticoagulation in patients with non-valvular AF who have moderate to high thromboembolic risk factors.