Dilatación de la aurícula izquierda en deportistas de alta competición y electrofisiología auricular / Left atrial enlargement in competitive athletes and atrial electrophysiology

Introducción y objetivos: Existe poca información sobre la dilatación de la aurícula izquierda (AI) y los parámetros electrocardiográficos en deportistas. Métodos: Estudio observacional multicéntrico en deportistas de competición y controles. La dilatación de la AI se definió como un volumen indexado por área de superficie corporal ≥ 34ml/m2. Se estudió su relación con parámetros electrocardiográficos auriculares. Resultados: Se incluyó en total a 356 sujetos: 308 deportistas de competición (media de edad, 36,4±11,6 años) y 48 controles (49,3±16,1 años). Los deportistas de competición tenían un mayor volumen medio indexado de la AI (29,8±8,6 frente a 25,6±8,0ml/m2; p=0,006) y una mayor prevalencia de dilatación de la AI (113 [36,7%] frente a 5 [10,4%]; p <0,001), sin diferencias relevantes en cuanto a la duración de la onda P (106,3±12,5 frente a 108,2±7,7 ms; p=0,31), la prevalencia de bloqueo interauricular (40 [13,0%] frente a 4 [8,3%]; p=0,36) ni la puntuación Morphology-Voltage-P-wave duration (1,8±0,84 frente a 1,5±0,8; p=0,71). El entrenamiento competitivo se asoció de manera independiente con la dilatación de la AI (OR=14,7; IC95%, 4,7-44,0; p < 0,001), pero no con la duración de la onda P (OR=1,02; IC95%, 0,99-1,04), el bloqueo interauricular (OR=1,4; IC95%, 0,7-3,1) o la puntuación Morphology-Voltage-P-wave duration (OR=1,4; IC95%, 0,9-2,2). Conclusiones: La dilatación de la AI es frecuente en deportistas de competición, pero no se acompaña de una modificación relevante en los parámetros electrocardiográficos (AU)

Introduction and objectives: There are scarce data on left atrial (LA) enlargement and electrophysiological features in athletes. Methods: Multicenter observational study in competitive athletes and controls. LA enlargement was defined as LA volume indexed to body surface area ≥ 34mL/m2. We analyzed its relationship with atrial electrocardiography parameters. Results: We included 356 participants, 308 athletes (mean age: 36.4±11.6 years) and 48 controls (mean age: 49.3±16.1 years). Compared with controls, athletes had a higher mean LA volume index (29.8±8.6 vs 25.6±8.0mL/m2, P=.006) and a higher prevalence of LA enlargement (113 [36.7%] vs 5 [10.4%], P <.001), but there were no relevant differences in P-wave duration (106.3±12.5ms vs 108.2±7.7ms; P=.31), the prevalence of interatrial block (40 [13.0%] vs 4 [8.3%]; P=.36), or morphology-voltage-P-wave duration score (1.8±0.84 vs 1.5±0.8; P=.71). Competitive training was independently associated with LA enlargement (OR, 14.7; 95%CI, 4.7-44.0; P <.001) but not with P-wave duration (OR, 1.02; 95%CI, 0.99-1.04), IAB (OR, 1.4; 95%CI, 0.7-3.1), or with morphology-voltage-P-wave duration score (OR, 1.4; 95%CI, 0.9-2.2). Conclusions: LA enlargement is common in adult competitive athletes but is not accompanied by a significant modification in electrocardiographic parameters (AU)

Advanced interatrial block as a substrate of supraventricular tachyarrhythmias: a well recognized syndrome.

Interatrial blocks (IABs) are well described and accepted in the scientific community. In the last four decades major discoveries were made including its physiopathology, ECG presentation, classification and association with atrial tachyarrhythmias (advanced IAB). This article will briefly review the state of the art on the understanding of advanced IAB as an electrical substrate for atrial tachyarrhythmias as well as the future directions.

Cardiac autonomic profile in different sports disciplines during all-day activity.

AIM: Physical training and sport activity have a beneficial effect on cardiac autonomic activity. However, the exact impact of different types of sports disciplines on cardiac autonomic function is still unclear. The aim of this study was to evaluate the cardiac autonomic profile in different sports discplines and to determine their impact on cardiac autonomic function by using heart rate variability (HRV), a noninvasive electrocardiographic (ECG) analysis of the sympatho-vagal balance. METHODS: Temporal and spectral HRV parameters determined from 24-hour continuous ECG monitoring were studied in 40 subjects, including 12 endurance athletes, 14 hockey players and 14 untrained male volunteers (control group). Each participant had to wear a Holter recorder during 24 hours and to continue his everyday activities. All HRV parameters were compared between the 3 study groups. RESULTS: All heart rate values were lower and all parasympathetic-related time domain indices, including root mean square of successive differences (RMSSD) and pNN50 (NN50 count divided by the total number of all NN intervals), were higher in both athletes groups as compared with controls (P<0.05). However, standard deviation of all NN intervals (SDNN) values, which determine global HRV, were significantly higher only in endurance athletes (P<0.05). Furthermore, the power spectral components low frequency (LF), a mixture of both autonomic inputs, and HF (high frequency), a marker of vagal modulation, were significantly higher with a resulting lower LF/HF ratio in both athletes groups as compared to controls (P<0.05). CONCLUSION: Both endurance and team playing athletic activity induce during all-day a high parasympathetic tone (higher RMSSD, pNN50 and HF, and lower LF/HF ratio). However, only endurance athletic activity has a particularly high global HRV (higher SDNN), indicating thereby that this type sports discipline may have a more substantially favorable effect on the cardiac autonomic profile.

Association between short term and long term communication in pathological autonomic control.

Autonomic Information Flow (AIF) reflects the time scale dependence of autonomic communications such as vagal, sympathetic, and slower rhythms and their complex interplay. We investigated the hypothesis that pathologically disturbed short term control is associated with simplified complex long term control. This particular characteristic of altered autonomic communication was evaluated in different medical patient groups. Holter recordings were assessed in patients with multiple organ dysfunction (MODS) (26 survivors, 10 non-survivors); with heart failure (14 low risk-without history of aborted cardiac arrest (CA), 13 high risk--with history of CA); with idiopathic dilated cardiomyopathy (IDC) (26 low risk, 11 high risk of CA), after myocardial infarction (MI) (1221 low risk--survivors, 55 high risk--non-survivors); after abdominal aorta surgery (AAS, 32 length of stay in hospital LOS>7 days, 62 LOS < or =7 days). AIF of short and long time scales was investigated. We found a fundamental association of increased short term randomness and decreased long term randomness due to pathology. Concerning risk, high risk patients were characterized by increased short term complexity and decreased long term complexity in all patients groups with the exception of the IDC patients. We conclude that different time scales of AIF represent specific pathophysiological aspects of altered autonomic communication and control. The association of altered short term control with simplified long term behavior might be a pathophysiologically relevant compensation mechanism in the case of a disturbed fastest actuator. This knowledge might be useful for the development of comprehensive therapeutic strategies besides the predictive implications.

Hidden markov models and mutual information analysis to characterize nonlinear dynamics in heart rate variability.

A study of nonlinear dynamics of the heart rate variability (HRV) was performed using hidden Markov models (HMM) and Mutual Information (MI). A methodology based on HMM has been developed in the present work. Cardiac RR series were analyzed in the three frequency bands: HF (0.15-0.45Hz), high frequency band; LF (0.04-0.15Hz), low frequency band; VLF (0.003-0.04Hz), very low frequency band. These series (0, observations) were modeled using HMM. The model λ=(A,B,∏) was selected so that P(O/λ) was locally maximized. Ergodic topology and N=10 states were also considered for this analysis. Different measures based on HMM were defined and obtained from RR time series of 37 Idiopathic Dilated Crdiomyopathy (IDC) patients and 46 healthy subjects (NRM), during awake and sleep stages. Two groups of IDC patients were considered: 11 high risk (HR) patients, after aborted sudden cardiac death (SCD) or who died during the follow up; 26 low risk (LR) patients, without SCD. Some HMM measures showed high percentages (up to 100%) of well classified subjects in all groups.

Moderate daily intake of red wine inhibits mural thrombosis and monocyte tissue factor expression in an experimental porcine model.

BACKGROUND: Moderate consumption of red wine has been epidemiologically associated with a reduction in cardiovascular disease, but its mechanism of action is not fully understood. The objective was to study whether the protective effects of a daily intake of red wine (Tempranillo, 12.8% alcohol vol/vol) could be related to inhibition of thrombosis in an experimental model of diet-induced hyperlipemia. METHODS AND RESULTS: For 100 days, animals were fed a western-type proatherogenic diet containing 2% cholesterol and 20% saturated fat. Three doses of red wine were studied (20, 30, and 40 g wine-ethanol/d) and compared with placebo-control animals not taking any wine. Thrombosis under flow conditions was evaluated by radioisotopic quantification of deposited platelets on damaged arteries. Changes in RhoA translocation in platelets and monocyte tissue factor expression were also analyzed. Mural platelet deposition was significantly reduced in animals ingesting red wine with their food. Expression of RhoA in the platelet cytoplasm (inactive form) was increased in wine-fed animals. Tissue factor mRNA expression in lipopolysaccharide-stimulated monocytes was reduced in wine-fed animals. Total cholesterol levels were not significantly different among groups. CONCLUSIONS: Moderate red wine intake significantly reduces platelet deposition triggered by damaged vessel wall, partially explained by inhibition of RhoA translocation to the platelet membrane. Hence, a daily moderate intake of wine seems to inhibit different pathways that converge in a reduced thrombotic risk on vessel wall injury.

Enoxaparin prevents death and cardiac ischemic events in unstable angina/non-Q-wave myocardial infarction. Results of the thrombolysis in myocardial infarction (TIMI) 11B trial.

BACKGROUND: Low-molecular-weight heparins are attractive alternatives to unfractionated heparin (UFH) for management of unstable angina/non-Q-wave myocardial infarction (UA/NQMI). METHODS AND RESULTS: Patients (n=3910) with UA/NQMI were randomized to intravenous UFH for >/=3 days followed by subcutaneous placebo injections or uninterrupted antithrombin therapy with enoxaparin during both the acute phase (initial 30 mg intravenous bolus followed by injections of 1.0 mg/kg every 12 hours) and outpatient phase (injections every 12 hours of 40 mg for patients weighing <65 kg and 60 mg for those weighing >/=65 kg). The primary end point (death, myocardial infarction, or urgent revascularization) occurred by 8 days in 14.5% of patients in the UFH group and 12.4% of patients in the enoxaparin group (OR 0.83; 95% CI 0.69 to 1.00; P=0. 048) and by 43 days in 19.7% of the UFH group and 17.3% of the enoxaparin group (OR 0.85; 95% CI 0.72 to 1.00; P=0.048). During the first 72 hours and also throughout the entire initial hospitalization, there was no difference in the rate of major hemorrhage in the treatment groups. During the outpatient phase, major hemorrhage occurred in 1.5% of the group treated with placebo and 2.9% of the group treated with enoxaparin (P=0.021). CONCLUSIONS: Enoxaparin is superior to UFH for reducing a composite of death and serious cardiac ischemic events during the acute management of UA/NQMI patients without causing a significant increase in the rate of major hemorrhage. No further relative decrease in events occurred with outpatient enoxaparin treatment, but there was an increase in the rate of major hemorrhage.

Elevated levels of plasmin-alpha2 antiplasmin complexes in unstable angina.

The evidence of elevated levels of several biochemical markers of prothrombotic state in patients with unstable angina suggests that thrombus formation and lysis play a pivotal role in acute coronary syndromes. The clinical syndrome of unstable angina encompasses a variety of clinical presentations of transient episodes of myocardial ischemia. This study was designed to assess plasmin generation in different settings of unstable angina. Evidence of plasmin generation in patients with unstable angina was measured by circulating plasmin-alpha2 antiplasmin complexes (PAP). A second objective was to identify whether PAP levels had a prognostic value to predict outcome. Eighty-five patients admitted to the coronary care unit for unstable angina were classified into three groups. Group A included 26 patients with postinfarction angina; group B comprised 26 patients with new onset angina; and group C included 33 patients with crescendo angina. Mean PAP levels were higher in the three groups compared to healthy controls. A significant correlation was found between levels of PAP and D-dimer, particularly in postinfarction angina (r = 0.6; p <0.0005). This trial adds new insights into the pathophysiology of unstable angina. It demonstrates that plasmin is generated in the different settings of unstable angina but particularly in postinfarction angina patients where a fibrin-rich thrombus is responsible of the symptoms. However, in this series PAP levels do not predict an uneventful outcome neither in the acute phase nor at long term (6 months).