Correspondence: routine early angioplasty after fibrinolysis

To the Editor: Cantor et al. (June 25 issue)1 conclude that among high-risk patients with ST-segment elevation myocardial infarction who receive fibrinolysis, prompt interhospital transfer for early percutaneous coronary intervention (PCI) after fibrinolysis is associated with significantly fewer ischemic complications than is standard treatment. Fundamental to this study’s findings are the criteria for identifying the high-risk patients who are likely to benefit from routine early angioplasty after fibrinolysis. ..................................................

Thermoregulation in people with spinal cord injury

Thermoafferent information is integrated at multiple levels within the central nervous system. However, due to the difficulty in differentiating thermoregulatory functions of the spinal cord from those of higher centres in humans, the role of the spinal cord in certain aspects of thermoregulation remains unclear. Subjects with spinal cord injury have unique neural changes providing an opportunity to evaluate the role of the spinal cord, independently of higher thermoregulatory centres. Subjects with (N=11) and without (N=11) spinal cord injury were studied in a series of experiments, in which a wide range of local and whole-body temperature changes and postural manipulations were imposed. During these trials, various physiological (skin temperature, core temperature, local sweat rate and sweat expulsion frequency - a measure of central sympathetic drive), and psychophysical variables (thermal sensation and discomfort) were investigated. Six key observations arose from these experiments: (i) Subjects with spinal cord injury had a lower thermoafferent capacity (secondary to neural damage) and a corresponding reduction in thermoefferent drive (sudomotor sensitivity of 4.2 versus 8.8 expulsions•min-1•,°C-1;in able-bodied; P=0.03). (ii) Equations used to approximate thermoafferent drive in able-bodied subjects, overestimated thermal feedback in subjects with spinal cord injury. However, this could be corrected by modifying the skin area weightings to include only the sensate areas. (iii) No subjects with physiologically-confirmed thermoefferent spinal cord injury displayed sweating from insensate skin sites, indicating that a spinal cord that has been isolated from higher centres cannot induce thermal sweating. (iv) Subjects with spinal cord injury had higher forehead sweat rates (0.77 versus 0.52 mg•cm-2•min-1; P=0.03), but an equivalent sweat sensitivity (1.24 versus 1.27 mg•cm-2•min-1•,°C-1; P=0.94), indicating the presence of a peripheral adaptation to sustain thermal homeostasis, and secondary to reduced thermal afferent and efferent flow. (v) Respiratory frequency increased more for a given increase in body temperature in subjects with spinal cord injury (2.4 versus 1.1 breaths•min-1•°C-1; P=0.042), but this did not provide a thermoregulatory benefit. (vi) Subjects with spinal cord injury demonstrated greater changes in behavioural thermoregulatory indicators (thermal sensation and discomfort) in response to standardised local and whole-body thermal loads. Collectively, these observations indicate the unique nature of thermoregulation in people with spinal cord injury and the adaptive ability of the human thermoregulatory system

Thermal sweating following spinal cord injury

A complete spinal cord injury prevents neural connections between distal sites and higher neural structures. While it has previously been demonstrated that an isolated spinal cord can elicit non-thermal sweating independently of the hypothalamus [1-3], the ability of the spinal cord to control sweating in response to thermal stimuli, without hypothalamic influence, is less clear. The majority of early literature indicates that thermal sweating is absent below a complete spinal cord injury (SCI) [4-7], yet several studies suggest otherwise [8-11]. However, invasive measures have failed to observe altered sympathetic activity when thermally stimulating insensate regions [12], which is inconsistent with the observations of sweating below a SCI

First-in-Human Experience and Acute Procedural Outcomes Using a Novel Pulsed Field Ablation System: The PULSED AF Pilot Trial

BACKGROUND: Pulsed field ablation (PFA) is a novel form of ablation using electrical fields to ablate cardiac tissue. There are only limited data assessing the feasibility and safety of this type of ablation in humans. METHODS: PULSED AF (Pulsed Field Ablation to Irreversibly Electroporate Tissue and Treat AF; https://www.clinicaltrials.gov; unique identifier: NCT04198701) is a nonrandomized, prospective, multicenter, global, premarket clinical study. The first-in-human pilot phase evaluated the feasibility and efficacy of pulmonary vein isolation using a novel PFA system delivering bipolar, biphasic electrical fields through a circular multielectrode array catheter (PulseSelect; Medtronic, Inc). Thirty-eight patients with paroxysmal or persistent atrial fibrillation were treated in 6 centers in Australia, Canada, the United States, and the Netherlands. The primary outcomes were ability to achieve acute pulmonary vein isolation intraprocedurally and safety at 30 days. RESULTS: Acute electrical isolation was achieved in 100% of pulmonary veins (n=152) in the 38 patients. Skin-to-skin procedure time was 160±91 minutes, left atrial dwell time was 82±35 minutes, and fluoroscopy time was 28±9 minutes. No serious adverse events related to the PFA system occurred in the 30-day follow-up including phrenic nerve injury, esophageal injury, stroke, or death. CONCLUSIONS: In this first-in-human clinical study, 100% pulmonary vein isolation was achieved using only PFA with no PFA system-related serious adverse events. Graphic Abstract: A graphic abstract is available for this article

Position Statement on the Management of Cardiac Electrophysiology and Cardiac Implantable Electronic Devices in Australia during the COVID-19 Pandemic: A Living Document

The COVID-19 pandemic poses a significant stress on health resources in Australia. The Heart Rhythm Council of the Cardiac Society of Australia and New Zealand aims to provide a framework for efficient resource utilisation balanced with competing risks when appropriately treating patients with cardiac arrhythmias. This document provides practical recommendations for the electrophysiology (EP) and cardiac implantable electronic devices (CIED) services in Australia. The document will be updated regularly as new evidence and knowledge is gained with time