Heat and cold stress increases the risk of paroxysmal supraventricular tachycardia.

Paroxysmal supraventricular tachycardia (PSVT) is a common arrhythmia in adults. Its occurrence depends on the presence of the reentry circuit and the trigger of the paroxysm. Stress, emotional factors, and comorbidities favour the occurrence of such an episode. We hypothesized that the occurrence of PSVT follows extreme thermal episodes. The retrospective analysis was based on the data collected from three hospital emergency departments in Poland (Olsztyn, Radom, and Wroclaw) involving 816 admissions for PSVT in the period of 2016-2021. To test the hypothesis, we applied the Universal Climate Thermal Index (UTCI) to objectively determine exposure to cold or heat stress. The risk (RR) for PSVT increased to 1.37 (p = 0.006) in cold stress and 1.24 (p = 0.05) in heat stress when compared to thermoneutral conditions. The likelihood of PSVT during cold/heat stress is higher in women (RR = 1.59, p< 0.001 and RR = 1.36, p = 0.024, respectively) than in men (RR = 0.64 at p = 0.088 and RR = 0.78, p = 0.083, respectively). The susceptibility for PSVT was even higher in all groups of women after exclusion of perimenopausal group of women, in thermal stress (RR = 1.74, p< 0.001, RR = 1.56, p = 0.029, respectively). Females, particularly at the perimenopausal stage and men irrespective of age were less likely to develop PSVT under thermal stress as compared to thermoneutral conditions. Progress in climate change requires searching for universal methods and tools to monitor relationships between humans and climate. Our paper confirms that the UTCI is the universal tool describing the impact of thermal stress on the human body and its high usefulness in medical researches.

Echocardiographic assessment of residuals after transvenous intracardiac lead extraction.

Detection of residual fibrotic tissue, called ghosts, after lead extraction is a new phenomenon in cardiology. This paper aims at describing the phenomenon of ghosts and determining their characteristic features. The study group consisted of 580 consecutive patients who underwent transvenous lead extraction (TLE) due to local infection, endocarditis and a superfluous lead. Each patient was clinically examined with the application of transthoracic echocardiography and transesophageal echocardiography directly before and after TLE. In the study population ghosts were detected in 110 patients (19%), and in 470 cases (81%) fibrotic tissue residuals were not found. Ghosts were most often located along the originally implanted lead's route. Longer ghosts were found after the removal of cardiac resynchronization therapy (CRT) and dual chamber pacing (DDD) devices. The local infection and infective endocarditis are associated with a larger number of ghosts revealed after the removal procedure (p = 0.006). The type of the implanted device: CRT/ICD/double chamber pacemaker/single chamber pacemaker, similar to the number of leads, did not impact on the number of the detected ghosts. The relationship between abrasions of the leads and the presence of ghosts proved significant, however (p = 0.043). TLE is associated with the presence of fibrotic tissue residuals in approx. 19% of patients. Indications for lead extraction due to local infection and endocarditis yielded significantly more cases of ghosts than in the entire patient population. The presence of abrasions is a good predictor for the presence of ghosts on the leads.