Background
For successful cardiac resynchronisation therapy (CRT) a spatial and electrical separation of right and left ventricular electrodes is essential. The spatial distribution of electrical delays within the coronary sinus (CS) tributaries has not yet been identified.Objective
Electrical delays within the CS are described during sinus rhythm (SR) and right ventricular pacing (RVP). A coordinate system grading the mitral ring from 0° to 360° and three vertical segments is proposed to define the lead positions irrespective of individual CS branch orientation.Methods
In 13 patients undergoing implantation of a CRT device 6±2.5, (median 5) lead positions within the CS were mapped during SR and RVP. The delay to the onset and the peak of the local signal was measured from the earliest QRS activation or the pacing spike. Fluoroscopic positions were compared to localizations on a nonfluoroscopic electrode imaging system.Results
During SR, electrical delays in the CS were inhomogenous in patients with or without left bundle branch block (LBBB). During RVP, the delays increased by 44±32 ms (signal onset from 36±33 ms to 95±30 ms; p<0.001, signal peak from 105±44 ms to 156±30 ms; p<0.001). The activation pattern during RVP was homogeneous and predictable by taking the grading on the CS ring into account: (% QRS) = 78−0.002 (grade−162)2, p<0.0001. This indicates that 78% of the QRS duration can be expected as a maximum peak delay at 162° on the CS ring.Conclusion
Electrical delays within the CS vary during SR, but prolong and become predictable during RVP. A coordinate system helps predicting the local delays and facilitates interindividual comparison of lead positions irrespective of CS branch anatomy. 相似文献Background
Although the assessment of diastolic dysfunction (DD) is an integral part of routine cardiologic examinations, little is known about associated electrocardiographic (ECG) changes. Our aim was to investigate a potential role of ECG indices for the recognition of patients with DD.Methods and Results
ECG parameters correlating with echocardiographic findings of DD were retrospectively assessed in a derivation group of 172 individuals (83 controls with normal diastolic function, 89 patients with DD) and their diagnostic performance was tested in a validation group of 50 controls and 50 patients. The patient group with a DD Grade 1 and 2 showed longer QTc (422±24ms and 434±32ms vs. 409±25ms, p<0.0005) and shorter Tend–P and Tend–Q intervals, reflecting the electrical and mechanical diastole (240±78ms and 276±108ms vs. 373±110ms, p<0.0001; 409±85ms and 447±115ms vs. 526±119ms, p<0.0001). The PQ–interval was significantly longer in the patient group (169±28ms and 171±38ms vs. 153±22ms, p<0.005). After adjusting for possible confounders, a novel index (Tend–P/[PQxAge]) showed a high performance for the recognition of DD, stayed robust in the validation group (sensitivity 82%, specificity 93%, positive predictive value 93%, negative predictive value 82%, accuracy 88%) and proved a substantial added value when combined with the indexed left atrial volume (LAESVI, sensitivity 90%, specificity 92%, positive predictive value 95%, negative predictive value 86%, accuracy 91%).Conclusions
A novel electrocardiographic index Tend–P/(PQxAge) demonstrates a high diagnostic accuracy for the diagnosis of DD and yields a substantial added value when combined with the LAESVI. 相似文献In Turkey, all heavy-vehicle driver’s license applicants older than 45 years and with body mass index (BMI) >25 kg/m2 are required to have polysomnography (PSG). However, this law is usually overlooked in practice due to the large number of applications. We aimed to assess the usefulness of four standardized questionnaires: Berlin, STOP, STOP-BANG and OSA50, in identifying the high-risk bus drivers for obstructive sleep apnea (OSA). Ninety highway bus drivers underwent polysomnography and completed four questionnaires. They also underwent otolaryngologic evaluation and blood testing for probable co-existing conditions such as diabetes and hypothyroidism. Neck circumference, BMI, waist circumference, prevalence of OSA and metabolic syndrome, oxygen desaturation index and duration of sleep associated with less than 90% saturation were significantly higher and mean oxygen saturation was significantly lower in drivers >45 years old than drivers <45 years old. STOP-BANG questionnaire had the highest sensitivity (87%) and the highest negative predictive value (NPV) (76%) in identifying high-risk for OSA. A cut off of 45 years old is suitable in screening highway bus drivers for OSA. Among the four questionnaires, STOP-BANG questionnaire had the highest sensitivity and negative predictive value (NPV) in identifying high risk patients for OSA in highway bus drivers and can be safely used as a screening test in this group.
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