Regional variations in heart failure: a global perspective.

Heart failure (HF) is a global public health concern that affects millions of people worldwide. While there have been significant therapeutic advancements in HF over the last few decades, there remain major disparities in risk factors, treatment patterns and outcomes across race, ethnicity, socioeconomic status, country and region. Recent research has provided insight into many of these disparities, but there remain large gaps in our understanding of worldwide variations in HF care. Although the majority of the global population resides across Asia, Africa and South America, these regions remain poorly represented in epidemiological studies and HF trials. Recent efforts and registries have provided insight into the clinical profiles and outcomes across HF patterns globally. The prevalence of HF and associated risk factors has been reported and varies by country and region ranges, with minimal data on regional variations in treatment patterns and long-term outcomes. It is critical to improve our understanding of the different factors that contribute to global disparities in HF care so we can build interventions that improve our general cardiovascular health and mitigate the social and economic cost of HF. In this narrative review, we hope to provide an overview of the global and regional variations in HF care and outcomes.

Ventricular fibrillation due to pheochromocytoma crisis in a previously asymptomatic patient.

Pheochromocytomas are catecholamine-producing tumors and a rare cause of sudden cardiac death. We describe the case of a previously healthy 28-year-old man who presented after a ventricular fibrillation out-of-hospital cardiac arrest (OHCA). His clinical investigation, including a coronary evaluation, was unremarkable. A protocolized head-to-pelvis computed tomography (CT) scan was ordered and revealed a large right adrenal mass with subsequent laboratory studies showing markedly elevated urine and plasma catecholamines. This raised suspicion for a pheochromocytoma as the underlying etiology behind his OHCA. He received appropriate medical management, underwent adrenalectomy with subsequent normalization of his metanephrines, and fortunately did not have recurrent arrythmias. This case highlights the first documented case of a ventricular fibrillation arrest as the initial presentation of pheochromocytoma crisis in a previously healthy individual, and how the use of early protocolized sudden death CT scan allowed for the prompt diagnosis and management of a rare cause of OHCA. Learning objective: We review the typical cardiac manifestations of pheochromocytoma and describe the first case of a pheochromocytoma crisis presenting as sudden cardiac death (SCD) in a previously asymptomatic individual. In young patients with unexplained SCD, it is important to consider pheochromocytoma in the differential diagnosis. We also review why an early head-to-pelvis sudden death computed tomography scan protocol may be helpful in the evaluation of patients resuscitated from SCD without an obvious etiology.

Ventricular fibrillation waveform measures and the etiology of cardiac arrest.

BACKGROUND: Early determination of the acute etiology of cardiac arrest could help guide resuscitation or post-resuscitation care. In experimental studies, quantitative measures of the ventricular fibrillation waveform distinguish ischemic from non-ischemic etiology. METHODS: We investigated whether waveform measures distinguished arrest etiology among adults treated by EMS for out-of-hospital ventricular fibrillation between January 1, 2006-December 31, 2014. Etiology was classified using hospital information into three exclusive groups: acute coronary syndrome (ACS) with ST elevation myocardial infarction (STEMI), ACS without ST elevation (non-STEMI), or non-ischemic arrest. Waveform measures included amplitude spectrum area (AMSA), centroid frequency (CF), mean frequency (MF), and median slope (MS) assessed during CPR-free epochs immediately prior to the initial and second shock. Waveform measures prior to the initial shock and the changes between first and second shock were compared by etiology group. We a priori chose a significance level of 0.01 due to multiple comparisons. RESULTS: Of the 430 patients, 35% (n=150) were classified as STEMI, 29% (n=123) as non-STEMI, and 37% (n=157) with non-ischemic arrest. We did not observe differences by etiology in any of the waveform measures prior to shock 1 (Kruskal-Wallis Test) (p=0.28 for AMSA, p=0.07 for CF, p=0.63 for MF, and p=0.39 for MS). We also did not observe differences for change in waveform between shock 1 and 2, or when the two acute ischemia groups (STEMI and non-STEMI) were combined and compared to the non-ischemic group. CONCLUSION: This clinical investigation suggests that waveform measures may not be useful in distinguishing cardiac arrest etiology.