Pulseless Idioventricular Rhythm Research Articles

Sudden cardiac arrest in intercollegiate athletes: Detailed analysis and outcomes of resuscitation in nine cases

Public access defibrillation programs have demonstrated a survival benefit in persons with out-of-hospital cardiac arrest. However, little is known about the effectiveness of early defibrillation in young competitive athletes with sudden cardiac arrest (SCA). The purpose of this study was to investigate the details and outcomes of resuscitation in a cohort of intercollegiate athletes with SCA. Nine cases of SCA in intercollegiate athletes occurring between 1999 and 2005 were identified through prior research and public media. A detailed questionnaire was completed by the certified athletic trainer involved in the resuscitation, and direct phone follow-up was achieved in every case. Nine intercollegiate athletes with SCA (4 basketball, 2 football, 2 lacrosse, and 1 swimming) had an average age of 21 years (range 18-30 years). All 9 athletes had a witnessed collapse, 7 occurred during practice, 1 during competition, and 1 during organized weight training. Cardiopulmonary resuscitation (CPR) was initiated within 30 seconds after cardiac arrest in 6 cases and by 1 minute in 2 additional cases. An automated external defibrillator (AED) was provided by an athletic trainer in 5 cases and by arriving emergency medical services (EMS) in 4 cases. The initial cardiac rhythm was confirmed or suspected ventricular fibrillation in 7 athletes, pulseless idioventricular rhythm in 1 case, and unknown in 1 case. In 7 cases a shock was deployed, with an average time from cardiac arrest to defibrillation of 3.1 minutes (range 1-7.5 minutes). The average time from arrest to defibrillation decreased significantly if an AED was provided by an athletic trainer as compared with the responding EMS (1.6 vs 5.2 minutes; P = .046). Eight of the 9 athletes died. The underlying cause of sudden cardiac death was hypertrophic cardiomyopathy in 5, commotio cordis in 2, and myocardial infarction in 1. Diagnostic studies in the survivor demonstrated no structural heart disease or precise cause of SCA. Despite witnessed collapse, immediate CPR, and prompt AED use in most cases, early defibrillation showed limited success, and survival was less than expected in this small cohort of intercollegiate athletes. More research is needed to determine the effectiveness of early defibrillation and factors that affect survival in young athletes with SCA.

An airline cardiac arrest program.

As many as 1000 lives are lost annually from cardiac arrest in commercial aircraft. Ventricular fibrillation (VF), the most common mechanism, can be treated effectively only with prompt defibrillation, whereas the current policy of most airlines is to continue cardiopulmonary resuscitation pending aircraft diversion. The objective of this study was to assess the impact of making semiautomatic external defibrillators (AEDs) available for use on airline passengers with cardiac arrest. AEDs were installed on international Qantas aircraft and at major terminals, selected crew were trained in their use, and all crew members were trained in cardiopulmonary resuscitation. Supervision was provided by medical volunteers or (remotely) by airline physicians. During a 64-month period, AEDs were used on 109 occasions: 63 times for monitoring an acutely ill passenger and 46 times for cardiac arrest. Twenty-seven episodes of cardiac arrest occurred in aircraft, often (11 of 27 [41%]) unwitnessed, and they were usually (21 of 27 [78%]) associated with asystole or pulseless idioventricular rhythm. All 19 arrests in terminals were witnessed; VF was present in 17 (89%). Overall, defibrillation was initially successful in 21 of 23 cases (91%). Long-term survival from VF was achieved in 26% (2 of 6 in aircraft and 4 of 17 in terminals). The ability to monitor cardiac rhythm aided decisions on diversion, which was avoided in most passengers with asystole or idioventricular rhythm. AEDs in aircraft and terminals, with appropriate crew training, are helpful in the management of cardiac emergencies. Survival from VF is practicable and is comparable with the most effective prehospital ambulance emergency services. Costly aircraft diversions can be avoided in clearly futile situations, enhancing the cost-effectiveness of the program.

External cardiac pacing for out-of-hospital bradyasystolic arrest

Cardiac pacing has been used successfully in patients with asystole or bradycardia compromising hemodynamics when it was applied soon after the onset of the event. An external cardiac pacemaker was used as part of initial resuscitative efforts for patients in primary, out-of-hospital, cardiac arrest who arrived in the emergency department in asystole, agonal rhythm, pulseless idioventricular rhythm, or bradycardia with hemodynamic compromise. A pulse was successfully generated in only one of twelve patients. That patient developed complete atrioventricular dissociation while in the emergency department. The nonresponding patients were in asystole or pulseless idioventricular rhythm when the pacemaker was applied. Pacing was initiated 1–13 minutes (mean 7 minutes) after arrival in the emergency department, but 27–90 minutes (mean 59 minutes) after arrest. The interval between arrest and application of the pacemaker was prolonged because of long periods for ambulance response, field resuscitation, and transport. It is concluded that the external cardiac pacemaker is a useful instrument for the treatment of bradyarrhythmias. While it may also be useful in the first few minutes after development of asystole, pulseless idioventricular rhythm, or agonal rhythm, it is of no benefit if applied long after the event.

High-dose corticosteroids in the treatment of pulseless idioventricular rhythm

Pulseless idioventricular rhythm (PIVR) is a slow electrical rhythm of ventricular origin without mechanical activity, and it is associated with a mortality rate that approaches 100%. In 1976 high-dose corticosteroids were advocated as beneficial in the treatment of PIVR. A critical review of the early literature suggests that the favorable outcome may have been attributable to variables other than treatment with high-dose steroids. Recent prospective clinical trials have not confirmed the salutory effect of steroids in this dysrhythmia.

MAST usage in cardiopulmonary resuscitation

The medical antishock trouser (MAST) has been advocated as potentially beneficial in the resuscitation of patients in cardiac arrest. Currently available data indicate that the MAST will increase the blood pressure generated by external cardiopulmonary resuscitation. In addition, there may be an increased survival of patients found in cardiac arrest with an initial cardiac rhythm of pulseless idioventricular rhythm when the MAST is used. The physiologic parameters affected by the MAST may be similar to those caused by vasopressor agents in animal studies and implicated in increased survival rates. The clinical implications of these data and their relation to future investigations are discussed.

Verapamil in the treatment of asystolic and pulseless idioventricular rhythm cardiopulmonary arrests: A preliminary report

A randomized, double-blinded study was conducted to evaluate the effectiveness of the calcium antagonist verapamil in patients in cardiopulmonary arrest with asystole or pulseless idioventricular rhythm (PIVR). Twenty-one such patients presenting to the emergency department received either verapamil (10 mg) or normal saline placebo in an intravenous bolus as initial therapy. They were then treated according to standard American Heart Association guidelines with the exception that calcium was not used. If these rhythms persisted after ten minutes, a second bolus of verapamil or saline was given. Resuscitation was successful in two of ten patients (20%) receiving verapamil and in one of 11 patients (9%) receiving placebo. This similar outcome (P = .462) in this small series suggests that verapamil may not add to successful resuscitation in these patients. Additional studies are needed to define the role of calcium and its antagonists in the treatment of asystole and PIVR.

Efficacy of pneumatic trousers in refractory prehospital cardiopulmonary arrest

Persons refractory to early application of advanced cardiac life support have a dismal prognosis. New modalities are needed to treat this almost universally lethal condition. We have evaluated pneumatic trousers in the treatment of refractory cardiopulmonary arrest. To date 136 patients have been entered into this controlled, prospective, randomized study. All patients were more than 20 years old and in cardiac arrest of apparent cardiac etiology. Patients were excluded if they had arrested secondary to trauma or overdose, or if an IV could not be started. In addition, patients had to be refractory to therapies included in our paramedic standing orders. If at the end of these standing orders the patient remained in arrest, he was entered into the study and pneumatic trousers were applied or not according to a randomized list. The attempted resuscitation was then continued with no other preset variables. The resuscitation and discharge rates for the control group were 21% and 4%, respectively. With pneumatic trousers, resuscitation increased to 33%, and discharge to 9%. The control group in ventricular fibrillation (VF) had a 27% resuscitation rate and a 5% discharge rate. The pneumatic trousers group with VF had a 35% resuscitation rate and a 12% discharge rate. In pulseless idioventricular rhythm (PIVR), the control group had a 0% resuscitation rate and a 0% discharge rate. In marked contrast, for PIVR the pneumatic trousers group had a 35% resuscitation rate and a 9% discharge rate. The control group in asystole (AS) had a 25% resuscitation rate and a 0% discharge rate. The pneumatic trousers group in AS had a 27% resuscitation rate and a 0% discharge rate. The improvement in resuscitation rate with pneumatic trousers was statistically significant only for the initial rhythm of PIVR (P less than .05). The pneumatic trousers improved resuscitation and discharge rates for refractory VF, but not to a statistically significant degree. These somewhat enhanced resuscitation and discharge rates with the pneumatic trousers make it an adjunct to be considered in refractory arrest.

Transthoracic pacing during CPR

Twenty-seven patients had transthoracic pacemakers inserted by the subxiphoid approach during advanced cardiopulmonary resuscitation (CPR) in the emergency department of Detroit General Hospital between May 1977 and March 1979. Twenty-one charts were available for detailed review. Pacemaker indications in these 21 cases included electromechanical dissociation in four cases, asystole in 10 cases, pulseless idioventricular rhythm in five cases, and 3 degree heart block in two cases. All patients had failed to respond to conventional chronotropic and inotropic agents prior to pacemaker insertion. Good pacemaker capture was obtained in eight of the 21 patients. Two of the patients with good capture had pulses for about 15 min after capture. One of these two patients rearrested, with signs of pericardial tamponade which was confirmed during emergency thoractomy. Neither of the two patients who had pulses after pacemaker insertion and capture could be stabilized, and both died within 30 min post-insertion. Transthoracic pacemaker insertion during advanced CPR in the emergency department probably does not improve outcome in bradyasystolic arrests if there has been poor response to standard advanced cardiac life support management.

His electrocardiographic characterization of terminal arrhythmias of hemorrhagic shock in dogs

Pulseless idioventricular rhythm is the agonal arrhythmia identified in three models of hemorrhagic shock used in this study. This arrhythmia is preceded by atrial and then junctional arrest demonstrated by His electrocardiography in all nine dogs studied. Two additional dogs were used as controls. Acid-base and electrolyte changes were not sufficient to cause the progressive failure of conduction system function seen so consistently. Patients receiving cardiopulmonary resuscitation who have profound bradycardia without pulses may have been in shock prior to cardiopulmonary arrest.

Incidence, etiology, and outcome of pulseless idioventricular rhythm treated with dexamethasone during advanced CPR

The cardiac resuscitation records of 458 patients who received advanced cardiac life support at Detroit General Hospital during the last two years were reviewed to identify patients who had pulseless idioventricular rhythm (PIVR) recognized and treated with dexamethasone. Twenty-five cases were identified. The initial successful resuscitation rate of 52% in these patients contrasts sharply with other published data indicating 100% failure with the use of conventional chronotropic drugs. The most common etiology of cardiac arrest in our patients who display PIVR during resuscitation is hypoperfusion shock. Dexamethasone may counteract the lethal arrhythmia by causing the release of aditional adenosine triphosphate into the cytoplasm from the mitochondria.

Pulseless idioventricular rhythm during CPR: An indication for massive intravenous bolus glucocorticoids

Five consecutive patients were initially resuscitated successfully from pulseless idioventricular rhythm with the use of 100 mg of dexamethazone administered by intravenous push after all conventional modes of management had failed. In this small series, two of the five patients are long-term survivors and the deaths of the other three patients are attributable to advanced underlying pathology. The possible mechanisms of action of the glucocorticoids are not conclusively known. There is a need for detailed laboratory study of Purkinje conduction and single-cell depolarization and mechanical patterns, under controlled settings approximating the clinical conditions.

Characterization of a myocardial depressant factor present in hemorrhagic shock.

Characterization of a myocardial depressant factor present in hemorrhagic shock.

The electrocardiogram in agonal states of man: Misao, T., Maéda, N., Tanaka, T., Noma, K., and itoh, S.: Ztschr. f. klin. Med. 130: 332, 1936

Cardiac pacing has been used successfully in patients with asystole or bradycardia compromising hemodynamics when it was applied soon after the onset of the event. An external cardiac pacemaker was used as part of initial resuscitative efforts for patients in primary, out-of-hospital, cardiac arrest who arrived in the emergency department in asystole, agonal rhythm, pulseless idioventricular rhythm, or bradycardia with hemodynamic compromise. A pulse was successfully generated in only one of twelve patients. That patient developed complete atrioventricular dissociation while in the emergency department. The nonresponding patients were in asystole or pulseless idioventricular rhythm when the pacemaker was applied. Pacing was initiated 1–13 minutes (mean 7 minutes) after arrival in the emergency department, but 27–90 minutes (mean 59 minutes) after arrest. The interval between arrest and application of the pacemaker was prolonged because of long periods for ambulance response, field resuscitation, and transport. It is concluded that the external cardiac pacemaker is a useful instrument for the treatment of bradyarrhythmias. While it may also be useful in the first few minutes after development of asystole, pulseless idioventricular rhythm, or agonal rhythm, it is of no benefit if applied long after the event.