Risk factors for the development of premature ventricular complex-induced cardiomyopathy: a systematic review and meta-analysis.

BACKGROUND: Premature ventricular complexes (PVCs) are a potentially reversible cause of heart failure. However, the characteristics of patients most likely to develop impaired left ventricular function are unclear. Hence, the objective of this study is to systematically assess risk factors for the development of PVC-induced cardiomyopathy. METHODS: We performed a structured database search of the scientific literature for studies investigating risk factors for the development of PVC-induced cardiomyopathy (PVC-CM). We investigated the reporting of PVC-CM risk factors (RF) and assessed the comparative association of the different RF using random-effect meta-analysis. RESULTS: A total of 26 studies (9 prospective and 17 retrospective studies) involving 16,764,641 patients were analyzed (mean age 55 years, 58% women, mean PVC burden 17%). Eleven RF were suitable for quantitative analysis (≥ 3 occurrences in multivariable model assessing a binary change in left ventricular (LV) function). Among these, age (OR 1.02 per increase in the year of age, 95% CI [1.01, 1.02]), the presence of symptoms (OR 0.18, 95% CI [0.05, 0.64]), non-sustained ventricular tachycardias (VT) (OR 3.01, 95% CI [1.39, 6.50]), LV origin (OR 2.20, 95% CI [1.14, 4.23]), epicardial origin (OR 4.72, 95% CI [1.81, 12.34]), the presence of interpolation (OR 4.93, 95% CI [1.66, 14.69]), PVC duration (OR 1.05 per ms increase in QRS-PVC duration [1.004; 1.096]), and PVC burden (OR 1.06, 95% CI [1.04, 1.08]) were all significantly associated with PVC-CM. CONCLUSIONS: In this meta-analysis, the most consistent risk factors for PVC-CM were age, non-sustained VT, LV, epicardial origin, interpolation, and PVC burden, whereas the presence of symptoms significantly reduced the risk. These findings help tailor stringent follow-up of patients presenting with frequent PVCs and normal LV function.

Echocardiographic predictors of mortality and morbidity in COVID-19 disease using focused cardiovascular ultrasound.

BACKGROUND: Focused transthoracic echocardiography (fTTE) has emerged as a critical diagnostic tool during the COVID-19 pandemic, allowing for efficient cardiac imaging while minimizing staff exposure. The utility of fTTE in predicting clinical outcomes in COVID-19 remains under investigation. METHODS: We conducted a retrospective study of 2,266 hospitalized patients at Rush University Medical Center with COVID-19 infection between March and November 2020 who received a fTTE. fTTE data were analyzed for association with primary adverse outcomes (60-day mortality) and with secondary adverse outcomes (need for renal replacement therapy, need for invasive ventilation, shock, and venous thromboembolism). RESULTS: Of the 427 hospitalized patients who had a fTTE performed (mean 62 years, 43% female), 109 (26%) had died by 60 days. Among patients with an available fTTE measurement, right ventricular (RV) dilation was noted in 34% (106/309), 43% (166/386) had RV dysfunction, and 17% (72/421) had left ventricular (LV) dysfunction. In multivariable models accounting for fTTE data, RV dilation was significantly associated with 60-day mortality (OR 1.93 [CI 1.13-3.3], p = 0.016). LV dysfunction was not significantly associated with 60-day mortality (OR 0.95 [CI: 0.51-1.78], p = 0.87). CONCLUSIONS: Abnormalities in RV echocardiographic parameters are adverse prognosticators in COVID-19 disease. Patients with RV dilation experienced double the risk for 60-day mortality due to COVID-19. To our knowledge, this is the largest study to date that highlights the adverse prognostic implications of RV dilation as determined through fTTE in hospitalized COVID-19 patients.

Anodal tDCS of the lower limb M1 does not acutely affect clinical blood pressure and heart rate in healthy and post stroke individuals.

Transcranial direct current stimulation (tDCS) is a non-invasive brain stimulation technique increasingly investigated an adjunct modality to enhance the effects of motor therapy. Although the safety of tDCS in relation to cognition, sensation and perception has been well reviewed, there still exists limited information regarding its effects on blood pressure and heart rate. As tDCS is being largely used in conjunction with stroke rehabilitation, it is important that we understand the effects of tDCS on autonomic function in the stroke population. In this retrospective study, we examined the acute effects of tDCS of the lower limb motor cortex in healthy and post stroke individuals using clinical measurements of blood pressure and heart rate. Fifteen minutes of 1 mA anodal tDCS did not cause any clinically detectable changes in blood pressure or heart rate. This is the first study to report the cardiovascular autonomic effects of tDCS of the lower limb M1 in healthy and post stroke individuals. Further studies are needed to examine if these safety effects are preserved during repeated applications of tDCS.

Polarity independent effects of cerebellar tDCS on short term ankle visuomotor learning.

BACKGROUND: Transcranial direct current stimulation (tDCS), an emerging technique of noninvasive brain stimulation, has shown to produce beneficial neural effects in consequence with improvements in motor behavior. There are not many studies examining the use of tDCS for lower limb motor control and learning. Most studies using tDCS for facilitating lower limb motor coordination have applied tDCS to the lower limb motor cortex (M1). As the cerebellum is also critically involved in movement control, it is important to dissociate the effect of tDCS on the cerebellum and M1 with respect to lower limb motor control before we begin the application of tDCS as a neuromodulatory tool. OBJECTIVE/HYPOTHESIS: The purpose of this study was to determine the effects of cerebellar vs. motor cortical tDCS on short term ankle visuomotor learning in healthy individuals. METHODS: Eight healthy individuals practiced a skilled ankle motor tracking task while receiving either facilitatory anodal tDCS to cerebellum, inhibitory cathodal tDCS to cerebellum, facilitatory anodal tDCS to M1, inhibitory cathodal tDCS to M1 or sham stimulation. Pre- and post-measures of changes in cortical excitability of the tibialis anterior muscle and measures of tracking accuracy were assessed. RESULTS: Anodal cerebellar, cathodal cerebellar, and anodal M1 stimulation improved target-tracking accuracy of the ankle. This was not dependent on the observed changes in motor cortical excitability of the tibialis anterior muscle. CONCLUSION(S): Polarity independent effects of tDCS on cerebellum were observed. The present study shows that modulation effects of tDCS can occur because of changes in the cerebellum, a structure implicated in several forms of motor learning, providing an additional way in which tDCS can be used to improve motor coordination.