Handling of Ventricular Fibrillation in the Emergency Setting

Abstract

Ventricular fibrillation (VF) and sudden cardiac death (SCD) are predominantly caused by channelopathies and cardiomyopathies in youngsters and coronary heart disease in the elderly. Temporary factors, e.g., electrolyte imbalance, drug interactions, and substance abuses may play an additive role in arrhythmogenesis. Ectopic automaticity, triggered activity, and reentry mechanisms are known as important electrophysiological substrates for VF determining the antiarrhythmic therapies at the same time. Emergency need for electrical cardioversion is supported by the fact that every minute without defibrillation decreases survival rates by approximately 7%-10%. Thus, early defibrillation is an essential part of antiarrhythmic emergency management. Drug therapy has its relevance rather in the prevention of sudden cardiac death, where early recognition and treatment of the underlying disease has significant importance. Cardioprotective and antiarrhythmic effects of beta blockers in patients predisposed to sudden cardiac death were highlighted in numerous studies, hence nowadays these drugs are considered to be the cornerstones of the prevention and treatment of life-threatening ventricular arrhythmias. Nevertheless, other medical therapies have not been proven to be useful in the prevention of VF. Although amiodarone has shown positive results occasionally, this was not demonstrated to be consistent. Furthermore, the potential proarrhythmic effects of drugs may also limit their applicability. Based on these unfavorable observations we highlight the importance of arrhythmia prevention, where echocardiography, electrocardiography and laboratory testing play a significant role even in the emergency setting. In the following we provide a summary on the latest developments on cardiopulmonary resuscitation, and the evaluation and preventive treatment possibilities of patients with increased susceptibility to VF and SCD.

Muerte Súbita Cardíaca por Fibrilación Ventricular asociada a isquemia miocárdica, tratada por Desfibrilador Automático Implantable

“…La MSC es el resultado final de una cadena de eventos que derivan en FV y paro cardiorespiratorio (PCR) produciendo una contracción irregular y caótica del miocardio ventricular. 2,4 La supervivencia tras PCR extrahospitalario es menor al 10%, de acuerdo a distintos registros, lo que dimensiona el impacto del manejo oportuno y su prevención. 10,11 El miocardio queda vulnerable por isquemia y/o altera- de reentrada en áreas isquémico-necróticas, automatismo anormal y actividad desencadenada por dispersión de períodos refractarios.…”

“…1 La MSC es la principal causa de muerte en el mundo,es responsable del 50% de las muertes cardiovasculares, afectando anualmente a 5 millones de personas al año, 700.000 en Europa y 400.000 en Estados Unidos, siendo más frecuente en hombres que en mujeres, 6.68 versus 1.4/100.000. 2 La cardiopatía isquémica (CI) es el substrato más frecuente de MSC, presentándose en el 80% de los casos. La incidencia de MSC asociada a CI es de 0.7/100.000 en personas entre 18-35 años y de 13.7 en mayores de 35.…”

“…3 La taquicardia ventricular (TV) y la fibrilación ventricular (FV) son las responsables del colapso circulatorio y MSC en el 85% de los sujetos, en el contexto de CI, desde la isquemia aguda hasta el infarto al miocardio (IAM). 2,4 El rol del desfibrilador automático implantable (DAI) es fundamental en la prevención de MSC por FV y TV, junto al control de los factores de riesgo cardiovascular y el tratamiento adecuado del síndrome coronario agudo (SCA). 5,6,7 A raíz del caso comunicado, se discute el concepto de isquemia miocárdica sin lesiones coronarias obstructivas (INOCA [8][9] : Ischemia and Non-Obstructive Coronary Artery Disease) y su eventual participación en la evolución clínica del paciente.…”

ECG for all patients in the PACU: Some say, why? I say, why not?

“…When patients are not connected to ECG in the PACU and the patient suffers a cardiac arrest, minutes may be wasted confirming an arrest has occurred; however, when an ECG trace confirms a shockable rhythm such as ventricular tachycardia or ventricular fibrillation, nurses immediately know what they are dealing with and vital minutes may be saved. Connecting a patient to an automated external defibrillator (AED) at the earliest possible moment is vital for patients who require this therapy, as survival rates decrease by approximately seven to ten per cent every minute without defibrillation 12 .…”

Two Targets, One Hit: new Anticancer Therapeutics to Prevent Tumorigenesis Without Cardiotoxicity

“…Therapy-related cardiovascular diseases involve a wide range of disorders from thromboembolism, stroke, systemic and pulmonary hypertension, myocarditis, cardiac arrhythmias to even sudden cardiac death, which collectively contribute to an increased morbidity and mortality of cancer patients. In addition to cardiovascular damage, a significant fraction of cancer patients suffers from acute or chronic kidney disease, requiring renal replacement therapies ( Czifra et al, 2013 ; Barta et al, 2014 ), resulting in an increased risk of atrial and ventricular arrhythmias, heart failure and other adverse effects ( Szabó et al, 2020 ). Nevertheless, increased prevalence of cancer among patients with heart failure indicates common molecular triggers and risk factors that contribute to both diseases ( de Boer et al, 2019 ; Meijers and De Boer, 2019 ).…”