Carnitine-acylcarnitine translocase deficiency
William L. Nyhan, Georg F. Hoffmann, Aida I. Al-Aqeel, Bruce A. Barshop in Atlas of Inherited Metabolic Diseases, 2020
Cardiomyopathy may be manifested by premature ventricular contractions, ventricular tachycardia, or hypotension [1], and bradycardia due to auriculoventricular block [3]. In one patient [1], the electrocardiogram showed ventricular hypertrophy and in another [3], a left bundle branch block. Echocardiogram showed reduced ejection fraction. Intracardiac conduction defects were seen in twin siblings who died after an episode days after onset at two months [12]. Over a period of 25 years, in 107 newborns, cardiac arrhythmia and conduction defects were the main presentations in patients with fatty acid oxidation defects [2]. Conduction disorders and atrial tachycardias were observed in patients with defects of long-chain fatty acid transport across the inner mitochondrial membrane (carnitine palmitoyl transferase type II deficiency [Chapter 38] and CACT deficiency) and in patients with trifunctional protein deficiency (Chapter 41). Arrhythmias have been attributed to the accumulation of intermediary metabolites of fatty acids, such as long-chain acylcarnitines [13].
Biology And Methodology Of Whole-Body Hyperthermia
Leopold J. Anghileri, Jacques Robert in Hyperthermia in Cancer Treatment, 2019
The completeness with which various workers have reported the cardiovascular and respiratory changes in their patients undergoing WBH has varied considerably. At identical peak temperatures, some differences in the observed cardiovascular responses are evident. All groups report an increase in heart rate with increasing esophageal temperature. Pettigrew et al.29 noted that while the maximum heart rate achieved was independent of the rate of core heating, faster heating (up to 6°/hr) was attended by a lag or slower acceleration of heart rate. Mean heart rates at peak temperature range from 131/min (Barlogie et al.38) to 172/min (Herman et al.54,55). Tachyarrythmias have been seen by some workers (15% in Larkin’s series30,41), fewer in the series of Barlogie38 and Herman,54 and none in the Bull series,37 or in Robins’ radiant heat Phase-I trial.92 Ventricular arrythmias were seen by Bull et al. when WBH was combined with doxorubicin.39 Of interest, premature ventricular contractions (PVCs) reported by Larkin et al. were difficult to control with lidocaine30 and fatal ventricular fibrillation in patients treated by Euler-Rolle et al. prompted institution of the ß-blocker, pindolol, once the pulse rose to 120 beats per min.36 PVCs occurring in patients of Parks and Barlogie, however, responded promptly to lidocaine. Peak heart rate noted in the Wisconsin radiant heat system at 41.8°C was ᔐ150 beats per min and no arrhythmias have occurred;92 all patients had an infusion of lidocaine running throughout the treatment.
Complications of Cardiopulmonary Resuscitation
Stephen M. Cohn, Matthew O. Dolich in Complications in Surgery and Trauma, 2014
VF or pulseless VT usually results from a primary cardiac event such as acute myocardial infarction or ischemia. The presence of antecedent multifocal premature ventricular contractions may serve as a warning sign for these serious conditions. Certain electrolyte disturbances, such as hypokalemia, hypomagnesemia, or hypocalcemia, may complicate or contribute to this scenario (Table 25.1). In cases of traumatic cardiac arrest, ventricular irritability may suggest air embolism or cardiac compression caused by a tension pneumothorax or pericardial tamponade. Electrocution with alternating current in the range of 100 mA–1 A can also cause VF (Table 25.2).
Current state of leadless pacemakers: state of the art review
Published in Expert Review of Cardiovascular Therapy, 2019
Muhammad R. Afzal, Nupur Shah, Georges Daoud, Mahmoud Houmsse
Deploying the Micra pacemaker requires a slow and very controlled motion that ends with the delivery system in the RV but around 2 device lengths away from the Micra pacemaker. This step-by-step approach begins with unlocking the tether and removing the tether pin once the desired implant location had been confirmed. A fine forward pressure on the delivery system is applied by slowly advancing the delivery system until a concave curve is seen at the bend of the system just proximal to the device cup. It is important to have adequate tip pressure to ensure stable attachment of the tines and good electrical measurements. Ensuring a more septal position of the device allows for the safe application of pressure at this stage of the procedure [18]. A fine balance exists between too much and too little pressure; if not enough pressure is applied fixation is likely to be inadequate and pacing parameters are likely to be poor. With experience, this fine balance is easily recognized and the operator will acquire a better feel for how much pressure to apply. Once adequate tip pressure is achieved, the device is deployed about halfway observing the tines exiting the device cup and engaging the tissue. Once the device is deployed halfway, the forward pressure on the delivery system is relieved by the gentle withdrawal of the delivery system from the introducer, which prevents any forward or superior movement of the cup on the device as the Micra is fully exposed. It is not uncommon to observe premature ventricular contractions during this part of the procedure.
The association of cannabis use and cardiac dysrhythmias: a systematic review
Published in Clinical Toxicology, 2020
John R. Richards, Eike Blohm, Kara A. Toles, Angela F. Jarman, Dylan F. Ely, Joshua W. Elder
There were 16 Level II clinical studies identified in our review in which heart rate greater than 100 beats per minute and/or cardiac dysrhythmia was noted, and these are discussed in chronological order (Table 1). The first study was published in 1971 by Johnson and Domino [4], in which 25 subjects smoked cannabis and experienced dose-related tachycardia as high as 150 beats per minute that persisted for several minutes. Two subjects were noted to have premature ventricular contractions and T wave changes. This was followed by a study by Beaconsfield et al. [5] in which ten subjects who smoked cannabis were noted to experience tachycardia, with five also having P and T wave changes. The next two studies demonstrated increased heart rate with both smoked cannabis and oral THC administration but no mention of electrocardiogram (ECG) abnormalities [6,7]. The two studies which followed in 1973, however, did include descriptions of ECG irregularities in addition to tachycardia associated with cannabis administration. Kochar and Hosko [8] reported ingestion of oral THC at higher doses resulted in tachycardia in six of seven subjects, T wave changes in two subjects, and ST segment elevation in one subject. In their study of 10 subjects, Roth and co-workers [9] reported overall tachycardia, premature ventricular contractions in four subjects, and sinus arrhythmia in two subjects.
Stimulation of abdominal and upper thoracic muscles with surface electrodes for respiration and cough: Acute studies in adult canines
Published in The Journal of Spinal Cord Medicine, 2018
James S. Walter, Joseph Posluszny, Raymond Dieter, Robert S. Dieter, Scott Sayers, Kiratipath Iamsakul, Christine Staunton, Donald Thomas, Mark Rabbat, Sanjay Singh
Anesthetized animals were instrumented for respiratory monitoring. Endotracheal tube pressure was recorded at the distal end outside of the canine, and esophageal pressure was measured at a location just rostral to the diaphragm utilizing a small balloon-tipped tube filled with water.11 A similar tube was advanced into the colon to a location 23 cm from the anus that was used to monitor abdominal pressure. A lead II electrocardiogram (EKG) was recorded using wire hook electrodes placed under the skin in the right upper and left lower limbs. The EKG recording was analyzed by the computer program to display heart rate (ADInstruments). Effects of stimulation on heart rate was only determined during the initial abdominal recruitment test because electrical field interference during the stimulation prevented this measurement during other tests.11 Effects of upper thorax stimulation on ventricular arrhythmia was assessed during post hoc analysis of the EKG recordings. Only ventricular contractions could be seen in the EKG recording during and shortly after stimulation because the electrical interference prevented assessment of atrial contractions. Ventricular arrhythmia was assessed by the occurrence of premature ventricular contractions or a series of high frequency ventricular contractions. The assessment could not determine the origin of the arrhythmia, atrial or ventricular, because of interference in the atrial EKG record. All recordings were obtained digitally (16-channel recorder, ADInstruments, Inc) and displayed on a computer screen.
Related Knowledge Centers
- Echocardiography
- Heart Rate
- Palpitations
- Purkinje Fibers
- Ventricle
- Heart Failure
- Electrocardiography
- Sinoatrial Node
- Arrhythmogenic Cardiomyopathy
- Tachycardia-Induced Cardiomyopathy