Study on the relationship between atrial high-rate episode and left atrial strain in patients with cardiac implantable electronic device.

Background: Although atrial high-rate episode (AHRE) and atrial fibrillation (AF) cannot entirely be identical, recent studies suggest AHRE is linked to AF development and shares some characteristics with AF regarding thromboembolism. At present, there is still lack of predictive indicators for AHRE and diagnostic methods and clinical indicators for AHRE in patients without cardiac implantable electronic device (CIED). The aim of this study was thus to explore the relationship between AHRE and left atrial (LA) strain parameters with the goal of identifying high-risk populations of AHRE by LA strain characteristics. Methods: From February 2022 to May 2023, a total of 105 CIED patients were enrolled and divided into two groups based on whether AHRE had occurred: AHRE (-) group (n=65) and AHRE (+) group (n=40). Real-time three-dimensional echocardiography (RT-3DE) technique was used to obtain the LA time-volume curve. The collected dynamic images were analyzed on the Echopac 204 workstation to obtain the parameters of LA. The four-dimensional automatic LA quantitative analysis (4D Auto LAQ) technology was used to analyze the LA strain parameters: LA reservoir longitudinal strain (LASr), LA conduit longitudinal strain (LAScd), LA contraction longitudinal strain (LASct), LA reservoir circumferential strain (LASr-c), LA conduit circumferential strain (LAScd-c), LA contraction circumferential strain (LASct-c). Correlation analysis was carried out using Binary logistic regression analysis. The area under the receiver operating characteristic (ROC) curve (AUC) was used to evaluate the diagnostic performance of LASct in AHRE. Results: Body surface area (BSA) [odds ratio (OR) =8.34, 95% confidence interval (CI): 1.32-72.30, P=0.037], LASct (OR =1.20, 95% CI: 1.05-1.39, P=0.013) and LA end-systolic volume (LAESV) (OR =1.02, 95% CI: 1.00-1.04, P=0.023) were the influencing factors of AHRE. Only LASct (OR =1.18, 95% CI: 1.01-1.38, P=0.041) was found to be an independent influencing factor of AHRE. This result remained significant after adjusting for age, sex, hypertension, diabetes, and stroke history. The ROC curve showed that the cut-off for predicting AHRE was LASct =-4.125% with sensitivity of 37.5% and specificity of 87.7%. Conclusions: This cross-sectional study found that decreased LASct (absolute value) is an independent risk factor for the AHRE and has diagnostic efficacy in certain degree for the occurrence of AHRE.

Radiofrequency catheter ablation for improving myocardial work in patients with ventricular pre-excitation.

Background: Previous studies have not consistently found significant improvements in left ventricular ejection fraction or global longitudinal strain (GLS) after radiofrequency catheter ablation (RFCA) in patients with ventricular pre-excitation. The aim of this study was thus to explore the effects of RFCA on left ventricular function in patients with ventricular pre-excitation using a new noninvasive echocardiographic method of myocardial work. Methods: A total of 34 patients with ventricular pre-excitation who underwent RFCA and 18 healthy controls were prospectively included in this study. Before and after participants underwent RFCA, electrocardiographic and echocardiographic data of the patients were collected at resting and pacing heart rates (HRs) of 100 beats per minute (bpm) and 120 bpm (controlled by high right atrial pacing during the procedure). Clinical data of the healthy controls at resting HR were also collected. A self-controlled paired sample t test was used to compare the differences before and after participants underwent RFCA. Results: After participants underwent RFCA, the global wasted work (GWW) of the included patients decreased (resting HR: 165.3±68.8 vs. 92.6±42.5 mmHg%, P<0.001; HR of 100 bpm: 276.3±121.2 vs. 187.9±96.0 mmHg%, P<0.001; HR of 120 bpm: 323.9±126.7 vs. 181.0%±74.3 mmHg%. P<0.001), while the global work efficiency (GWE) increased (resting HR: 91.5%±3.8% vs. 94.9%±1.6%; P<0.001; HR of 100 bpm: 87.0%±5.2% vs. 91.0%±3.3%, P<0.001; HR of 120 bpm: 85.0%±5.1% vs. 90.3%±3.7%, P<0.001). Conclusions: In patients with ventricular pre-excitation, impaired GWW and GWE can be improved with RFCA. In clinical practice, noninvasive myocardial work assessment can be used in patients with ventricular pre-excitation.

Minimum heart rate and mortality in critically ill myocardial infarction patients: an analysis of the MIMIC-III database.

BACKGROUND: Low minimum heart rate (MHR) is common in critically ill myocardial infarction (MI) patients. However, the association between MHR and the mortality of critically ill MI patients remains unclear. METHODS: In this retrospective cohort study, a total of 2,031 critically ill MI patients were enrolled from the Medical Information Mart for Intensive Care (MIMIC)-III database. Patients were divided into a low MHR group [MHR <60 beats per minute (bpm)] and a high MHR group (MHR ≥60 bpm). A Cox proportional hazard model was used to elucidate the association between these two groups and the mortality of MI patients. The association between mortality and MHR as a continuous variable was analyzed non-parametrically using restricted cubic splines. Sensitivity analyses were conducted to determine the impact of different admission heart rate, hypertension, atrial fibrillation, and vasopressor use on our results. RESULTS: MI patients in the low MHR group had higher 30-day and 1-year mortality than those in the high MHR group (20.59% vs. 10.91%, P<0.001 and 29.76% vs. 19.31%, P<0.001, respectively). After adjustment, the low MHR group was significantly correlated with 30-day mortality [hazard ratio, 1.779, 95% confidence interval (CI), 1.400-2.261, P<0.001] and 1-year mortality (hazard ratio, 1.537, 95% CI, 1.272-1.859, P<0.001). This correlation remained remarkable in patients with low or high admission heart rate, with or without hypertension, and with or without atrial fibrillation. An apparent L-curve relationship was observed between the 30-day mortality or 1-year mortality and MHR as a continuous variable. CONCLUSIONS: MHR under 60 bpm may be associated with a higher risk for both 30-day and 1-year mortality in critically ill MI patients. These findings highlight the possibility of MHR as an early risk indicator and potential therapeutic target for mortality in critically ill MI patients, which warrants further investigation.

Assessment of Cardiac Lead Perforation: Comparison Among Chest Radiography, Transthoracic Echocardiography and Electrocardiography-gated Contrast-enhanced Cardiac CT.

OBJECTIVES: Cardiac lead perforation is a rare but potentially life-threatening event. The purpose of this study was to investigate the diagnostic performances of chest radiography, transthoracic echocardiography (TTE) and electrocardiography (ECG)-gated contrast-enhanced cardiac CT in the assessment of cardiac lead perforation. METHODS: This retrospective study was approved by the ethics review board of Sun Yat-Sen Memorial Hospital at Sun Yat-Sen University (Guangzhou, China), and the need to obtain informed consent was waived. Between May 2010 and Oct 2017, 52 patients were clinically suspected to have a cardiac lead perforation and received chest radiography, TTE and ECG-gated contrast-enhanced cardiac CT. Among them, 13 patients were identified as having cardiac lead perforation. The diagnostic performances of these three modalities were evaluated by receiver-operating characteristic (ROC) curves using a composite reference standard of surgical and electrophysiological results and clinical follow-up. The areas under ROCs (AUROCs) were compared with the McNemar test. RESULTS: The accuracies of chest radiography, TTE and ECG-gated contrast-enhanced cardiac CT imaging for the diagnosis of cardiac lead perforation were 73.1%, 82.7% and 98.1%, respectively. ECG-gated contrast-enhanced cardiac CT had a higher AUROC than chest radiography (p < 0.001) and TTE (p < 0.001). CONCLUSIONS: ECG-gated contrast-enhanced cardiac CT is superior to both chest radiography and TTE imaging for the assessment of cardiac lead perforation. KEY POINTS: • ECG-gated contrast-enhanced cardiac CT has an accuracy of 98.1% in the diagnosis of cardiac lead perforation. • The AUROC of ECG-gated contrast-enhanced cardiac CT is higher than those of chest radiography and TTE imaging. • ECG-gated contrast-enhanced cardiac CT imaging has better diagnostic performance than both chest radiography and TTE imaging for the assessment of cardiac lead perforation.

Carotid Artery Stenting Versus Carotid Endarterectomy for Treatment of Asymptomatic Carotid Artery Stenosis.

Asymptomatic carotid stenosis is common and is associated with increased risk of stroke. The relative efficacy and safety of carotid endarterectomy (CEA) and carotid stenting (CAS) in patients with asymptomatic carotid stenosis remain unclear. Five studies that recruited patients with asymptomatic but significant carotid stenosis, who underwent CEA or CAS, were included in this systematic review and meta-analysis. The analyzed outcomes included risks of stroke, myocardial infarction (MI), and death. Risk ratio (RR) and 95% confidence interval (95% CI) were calculated and pooled for meta-analysis. Pooled analysis demonstrated that compared with CEA, CAS was associated with a decreased risk of MI (RR = 0.49, 95%CI = 0.26-0.91, P = 0.023) and slightly increased risk of stroke, although not significant (RR = 1.69, 95% CI = 0.97-2.92, P = 0.063). There was no difference in the death rates between the groups (RR = 0.60, 95% CI = 0.17-2.18, P = 0.436). In the subgroup analysis, CAS was associated with a decreased risk of MI in mixed patients (RR = 0.45, 95% CI = 0.26-0.78, P = 0.005), but not in asymptomatic patients (RR = 0.549, 95% CI = 0.26-1.17, P = 0.119). Compared with CAS, CEA was associated with decreased risk of perioperative stroke and increased risk of MI; it did not affect the risk of death in patients with asymptomatic carotid stenosis. In the subgroup analysis, the decreased risk of MI after CAS was significant only in the mixed patients group. CAS was associated with higher risk of stroke but lower risk of MI than those with CEA. Both procedures appeared equivalent in terms of the risk of death.

Effects of anti-hypertensive treatment on major cardiovascular events in populations within prehypertensive levels: a systematic review and meta-analysis.

Uncertainties still remain in terms of the efficacy of anti-hypertensive treatment on the risk of major cardiovascular (CV) events within prehypertensive levels. This review aims to assess the efficacy and safety of anti-hypertensives on the CV risks in populations within prehypertensive levels. Randomized controlled trials (RCTs) concerning active treatment vs placebo in populations within prehypertensive levels were identified through electronic database and manual search. Outcomes included the first co-primary outcomes, stroke, heart failure (HF), myocardial infarction (MI), all-cause mortality, and cardiovascular mortality. The first co-primary outcomes were defined as composite cardiovascular disease (CVD) events in the included studies. A total of 29 RCTs involving 127,641 participants were identified. Pooled analysis showed active treatment was associated with a significant 7% reduction in risk of the first co-primary outcomes, 14% in stroke, and 10% in HF as compared to placebo (0.86, 0.77-0.96; 0.93, 0.89-0.98; and 0.90, 0.83-0.97). However, there were no significant reductions in risk of MI, all-cause mortality, and cardiovascular mortality. A significant reduction in risk of the first co-primary outcomes was observed in subpopulations with systolic blood pressure (SBP) 130-139 mmHg (0.94, 0.89-0.99) or prior CVDs (0.88, 0.82-0.94). Meta-regression analyses showed no significant relative risk reductions proportional to the magnitude of the mean baseline BP, mean on-treatment BP, the mean absolute change in BP, the proportion of patients with hypertension, and mean age. In summary, anti-hypertensive treatment has beneficial cardiovascular effects in populations within prehypertensive levels, especially in subpopulations with SBP 130-139 mmHg or prior CVDs.

Stretch-activated channel Piezo1 is up-regulated in failure heart and cardiomyocyte stimulated by AngII.

Mechanotransduction is the conversion of extracellular mechanical stimuli into intracellular biochemical signals, and plays an important role in heart responses to its own mechanical environment. Piezo1 as a distinct stretch-activated channel (SAC) in mammal involves in not only vascular remodeling during embryonic development but also arterial remodeling upon to hypertension at adult stage. In the present study, the expression of Piezo1 was up-regulated in failure heart induced by myocardial infarction (MI) by real-time PCR, Western blot and immunohistochemistry analysis. Expression of Piezo1 mRNA and protein was enhanced by AngiotensinII (AngII) in neonatal rat ventricular myocytes via AT1 receptor depended methods. Furthermore, the Piezo1 expression was attenuated by Erk1/2 chemical inhibitor (U0126) only, but not by p38 MAPK inhibitor (SB203580), or JNK inhibitor (SP600125). Finally, systolic function improvement followed by chronic treatment with angiotensin receptor blocker (ARB) losartan prevented Piezo1 up-regulation in failure heart in vivo. In conclusion, our studies linked mechanotransduction which involved renin-angiotensin system that mediated up-regulation of Piezo1 to a clinically relevant heart failure.