RESUMEN
Background: Determining the mechanism of supraventricular tachycardias with prolongedP ventriculoatrial (VA) intervals is sometimes a challenge. Our objective is to analyse the determinants, time course and diagnostic accuracy (atypical atrioventricular nodal reentrant tachycardias [AVNRT] versus orthodromic reentrant tachycardias through an accessory pathway [ORT]) of spontaneous VA intervals variation in patients with narrow QRS tachycardias and prolonged VA. Methods: A total of 156 induced tachycardias were studied (44 with atypical AVNRT and 112 with ORT). Two sets of 10 measurements were performed for each patientafter tachycardia induction and one minute later. VA and VV intervals were determined. Results: The difference between the longest and the shortest VA interval (Dif-VA) correlates significantly with the diagnosis of atypical AVNRT (C coefficient = 0.95 and 0.85 after induction and at one minute, respectively; p < 0.001). A Dif-VA ≥ 15 ms presents a sensitivity and specificity for atypical AVNRT of 50% and 99%, respectively after induction, and of 27% and 100% one minute later. We found a robust and significant correlation between the fluctuations of VV and VA intervals in atypical AVNRTs (Coefficient Rho: 0.56 and 0.76, after induction and at one minute, respectively; p < 0.001 for both) but not in ORTs. Conclusions: The analysis of VA interval variability after induction and one minute later correctly discriminates atypical AVNRT from ORT in almost all cases.
RESUMEN
BACKGROUND: Syncope in a patient with a pacemaker is a serious event requiring urgent action to ascertain its cause. Around 5% of cases are due to a pacemaker system malfunction. CASE SUMMARY: An 82-year-old man underwent dual-chamber permanent pacemaker implantation due to intermittent high-degree atrioventricular block (AVB) in sinus rhythm. Nine months later, the patient reported episodes of syncope. The chest X-ray showed both leads to be at their expected positions. The electrocardiography (ECG) showed common atrial flutter. Ventricular capture during pacing in atrial demand pacing (AAI) mode confirmed cross-stimulation due to the switching of the atrial and ventricular leads at the pacemaker header. DISCUSSION: Cross-stimulation is a rare possibility in a differential diagnosis of causes of syncope. The diagnosis is frequently made during the procedure or a few hours later. The lack of symptoms during 9 months in this case was likely due to the patient having normal sinus rhythm with preserved AV conduction most of the time, as well as ventricular capture from the atrial lead related to non-sensed P waves. When atrial arrhythmias occurred, the sensing of the F waves inhibited ventricular pacing. In order to avoid this complication, in patients with intermittent bradycardia, pacing at a slightly higher heart rate during implantation of the device should be recommended to see the chamber paced with the surface ECG connected to the device interrogator. The ECG and electrogram (EGM) should correlate during device interrogation in order to identify this complication.).
RESUMEN
To analyze the clinical profile and therapeutic strategy in atrial fibrillation (AF) according to gender in a contemporaneous patient cohort a prospective, multicenter observational study was performed on consecutive patients diagnosed with AF and assessed by cardiology units in the region of Galicia (Spain). A total of 1007 patients were included, of which 32.3% were women. The mean age of the women was significantly greater than that of the men (71.6 versus 65.7 years; p < 0.001), with a higher prevalence of hypertension (HTN) and valve disease. Women more often reported symptoms related to arrhythmia (28.2% in EHRA class I versus 36.4% in men), with a poorer level of symptoms (EHRA classes IIb and III). Thromboembolic risk was significantly higher among women (CHA2DS2-VASc 3 ± 1.3 versus 2 ± 1.5), in the same way as bleeding risk (HAS-BLED 0.83 ± 0.78 versus 0.64 ± 0.78) (p < 0.001), and women more often received anticoagulation therapy (94.1% versus 87.6%; p = 0.001). Rhythm control strategies proved significantly less frequent in women (55.8% versus 66.6%; p = 0.001), with a lesser electrical cardioversion (ECV) rate (18.4% versus 27.3%; p = 0.002). Perceived health status was poorer in women. Women were older and presented greater comorbidity than men, with a greater thromboembolic and bleeding risk. Likewise, rhythm control strategies were less frequent than in men, despite the fact that women had poorer perceived quality of life and were more symptomatic.
Asunto(s)
COVID-19 , Nodo Sinoatrial , Arritmias Cardíacas , Electrocardiografía , Humanos , SARS-CoV-2RESUMEN
Telomere length is related to cellular aging and cardiovascular disease. Nevertheless, the specific role of cellular aging in this process is still unclear. The aim of this report was to analyze the prognostic value of telomere length in men admitted for acute coronary syndrome. Telomere length was measured by quantitative polymerase chain reaction in peripheral blood leukocytes of 203 men classified into 2 groups: those aged 50 to 75 years and those >75 years. Clinical follow-up had been done for >600 days, and a prognostic combined event was defined. In men aged 50 to 75 years, we found a statistically significant worse prognosis in patients with short telomeres (log-rank: 5.22, p <0.05) but not in men >75 years (log-rank: 0.01, p = 0.91). Cox analysis confirmed short telomeres in men aged 50 to 75 years as an independent prognostic risk factor. In conclusion, telomere length is a good predictor of cardiovascular prognosis in men admitted for acute coronary syndrome, but this relation depends on the chronological age of the population studied.