Blood oxygen saturation during atrio-ventricular dissociation with wide-QRS complex tachycardias

Amplitude ratios of two adjacent mixed blood oxygen saturation curve peaks in randomly selected strips of ECG were analysed in 32 patients with regular wide-QRS complex tachycardias and 60 control subjects where pacing was performed before ablation of narrow-QRS complex tachycardias. Patients with VT showed different patterns of A-to-V relationships, leading to varying ratios of SpO2 adjacent peak amplitudes, in contrast to patients with aberrant SVTs and 1:1 AV association. Application of a criterion of adjacent SpO2 peaks differing by twofold or more had a sensitivity of 90.0% and specificity of 83.3% to detect AV dissociation during VT. Fluctuations on the mixed oxygen saturation curve may be a useful non-invasive clinical parameter to detect different ventricular filling caused by atrio-ventricular dissociation during VT.     

A High Prevalence of Intracranial Stenosis in Patients with Coronary Artery Disease and the Diagnostic Value of Transcranial Duplex Sonography

Background: According to the data from the population-based Rotterdam study, intracranial carotid artery calcification detected by computed tomography is very common and contributed to 75% of all strokes. The aim of the present study was to estimate the prevalence of intracranial stenosis (IS) using noninvasive transcranial color-coded duplex sonography (TCCS) in neurologically asymptomatic patients with coronary artery disease (CAD). Methods: Three hundred and eighty-nine patients with angiographically-confirmed, severe CAD were included prospectively. All of them were examined using extracranial and TCCS. Results: Out of 389 patients (age 66.7 ± 9.2, 39-88), 237 (61%) were diagnosed with 3 vessels disease and 152 patients (39%) with left stem disease with/without 3 vessels damage. Transcranial sonography revealed at least 1 IS in 63.6% of echo positive patients (220/346). IS was found in 127 (61.4%) patients with 3 vessels disease, 20 patients (58.8%) with isolated left stem disease, and 73 patients (69.5%) with 3 vessels and left stem disease (P?=?.305). In the case of significant (≥50%) extracranial internal carotid artery stenosis, intracranial stenosis were detected in 84.8% (50 of 59), in the case of mild (<50%) stenosis, in 59.2% (170 of 287), P < .001. Conclusions: It was found that two thirds of patients with advanced CAD have a silent IS. TCCS is a reliable method for the evaluation of intracranial atherosclerosis in such patients in order to gain useful information about cerebrovascular disease as a risk factor for stroke.     

Chest pain in the emergency department: From score to core—A prospective clinical study

High-sensitivity troponin assay brought new challenges as we detect elevated concentration in many other diseases, and it became difficult to distinguish the real cause of this elevation. In this notion, diagnosis of acute coronary syndrome (ACS) remains a challenge in emergency department (ED).We aim to examine different approaches for rule-in and rule-out of ACS using risk scores, copeptin, and coronary computed tomography angiography (CCTA).A prospective observational study was designed to evaluate chest pain patients. Consecutive adult patients admitted to the ED with a chief complaint of chest pain due to any cause were included.All patients were followed-up for 6 months after discharge for major adverse cardiovascular events and readmissions. Admission data, ED processes, and diagnoses were analyzed.One hundred forty-six patients were included, average age was 63 ± 13.4 years, and 95 (65.1%) were male. Global Registry of Acute Coronary Events (GRACE) and History, ECG, Age, Risk factors, Troponin (HEART) scores showed good prognostic abilities, but HEART combination with copeptin improves diagnoses of myocardial infarction (area under the curve [AUC] 0.764 vs AUC 0.864 P = .0008). Patients with elevated copeptin were older, had higher risk scores, and were more likely to be admitted to hospital and diagnosed with ACS in ED. For copeptin, AUC was 0.715 (95% confidence interval 0.629–0.803), and for combination with troponin, AUC of 0.770 (0.703–0.855) did not improve rule-in of myocardial infarction. High-sensitivity troponin I assay alongside prior stroke, history of carotid stenosis, dyslipidemia, use of diuretics, and electrocardiogram changes (left bundle branch block or ST depression) are good predictors of myocardial infarction (χ² = 52.29, AUC = 0.875 [0.813–0.937], P < .001). The regression analysis showed that combination of copeptin and CCTA without significant stenosis can be used for ACS rule-out (χ² = 26.36, P < .001, AUC = 0.772 [0.681–0.863], negative predictive value of 96.25%).For rule-in of ACS, practitioner should consider not only scores for risk stratification but carefully analyze medical history and nonspecific electrocardiogram changes and even with normal troponin results, we strongly suggest thorough evaluation in chest pain unit. For rule-out of ACS combination of copeptin and CCTA holds great potential.     

Hypertension and cardiac arrhythmias

Arterial hypertension is a widespread disease and one of important yet under-recognized and under-treated causes of atrial and ventricular arrhythmias. Hypertrophy of cardiac muscle in hypertensive patients is characterized not only by increased myocardial mass, but also by proliferation of fibrous tissue and decreased intercellular coupling, that lead to inhomogeneity of electrical properties and propensity to various arrhythmias. Many trials show the importance of treating hypertension in order to restore normal myocardial function and decrease the number of premature beats, runs of ventricular tachycardia, and attacks of atrial fibrillation. To date, the most convincing data are collected regarding the importance of blockade of renin-angiotensin-aldosterone system (RAAS) in order to avoid arrhythmias in arterial hypertension. Other antihypertensive drug classes (eg beta-blockers, calcium antagonists) are also useful, and investigational compounds that aim at regression of hypertrophy are under search. Polymorphism of genes coding the function of RAAS, pathways of synthesis and degradation of proteins and other cardiac and extracardiac systems involved in regulation of blood pressure, are recognized as promising targets for research.     

Impact of copper and zinc mixture on haematological parameters of rainbow trout (Oncorhynchus mykiss): acute exposure and recovery

Ecotoxicology - Significant changes in composition of rainbow trout Oncorhynchus mykiss blood cells types were induced after 4-days exposure with mixture of Cu2+ and Zn2+ at 0.25, 0.125 and 0.06...