Early repolarization syndrome: electrocardiographic signs and clinical implications.

Early repolarization syndrome (ERS) was previously considered as a benign variant, but it has recently emerged as a risk marker for idiopathic ventricular fibrillation (VF) and sudden death. As measured by electrocardiogram (ECG), early repolarization is characterized by an elevation of the J point and/or ST segment from the baseline by at least 0.1 mV in at least two adjoining leads. In particular, early repolarization detected by inferior ECG leads was found to be associated with idiopathic VF and has been termed as ERS. This condition is mainly observed in young men, athletes, and blacks. Also, it has become evident that electrocardiographic territory, degree of J-point elevation, and ST-segment morphology are associated with different levels of risk for subsequent ventricular arrhythmia. However, it is unclear whether J waves are more strongly associated with a depolarization abnormality rather than a repolarization abnormality. Several clinical entities can cause ST-segment elevation. Therefore, clinical and ECG data are essential for differential diagnosis. At present, the data set is insufficient to allow risk stratification in asymptomatic individuals. ERS, idiopathic VF, and Brugada syndrome (known as J-wave syndromes) are three clinical conditions that share many common ECG features; however, their clinical consequences are remarkably different. This review summarizes the current electrocardiographic data concerning ERS with clinical implications.

Predictive value of thromboembolic risk scores before an atrial fibrillation ablation procedure.

INTRODUCTION: It is not clear whether transesophageal echocardiography (TEE) should be performed prior to a planned atrial fibrillation (AF) ablation in all patients. METHODS AND RESULTS: The objectives of this study were to determine in 681 consecutive patients: (i) the relationship between the CHADS2 and CHA2DS2-VASc scores, the presence of a thrombogenic milieu and left atrial (LA) volume; (ii) the need for TEE in patients with low and intermediate thromboembolic risk assessed; and (iii) the predictive accuracy of the these 2 scores for the presence of thrombi in the LA/LAA (LA appendage) before a planned AF ablation. The prevalence of thrombi was 1%. All patients with thrombi had LA dilatation, a CHADS2 score ≥ 1 and a CHA2DS2-VASc score ≥ 2. CHADS2 or CHA2DS2-VASc scores <2 had an almost maximal negative predictive capability of excluding the presence of a thrombus (99.8% and 100%, respectively; 95% CI: 99-100). A CHADS2 score ≥ 2 had a sensitivity and specificity of 86% (95% CI: 42-100) and 82% (95% CI: 79-85), respectively, to predict the presence of a thrombus in the LA/LAA, while a CHA2DS2-VASc score ≥ 2 had a sensitivity and specificity of 100% (95% CI: 59-100) and 67% (95% CI: 63-70). The area under the curve for CHADS2 and CHA2DS2-VASc scores ≥ 2 was 0.928 (95% CI: 0.906-0.946) and 0.933 (95% CI: 0.912-0.951), respectively. CONCLUSION: Not all patients undergoing planned endocardial pulmonary vein isolation need preprocedural TEE. Both scores <2 had an almost maximal negative predictive capability of excluding the presence of a thrombus in the LA/LAA.

Chronic kidney disease: Prognostic marker of nonfatal pulmonary thromboembolism.

OBJECTIVE: Renal dysfunction is associated with increased cardiovascular morbidity and mortality. The alteration in renal function as a marker of mortality in pulmonary thromboembolism (PTE) has not been studied extensively. METHODS: Four hundred four consecutive patients diagnosed with non-high-risk PTE (without cardiogenic shock or blood pressure <90 mm Hg) were prospectively enrolled in the study between 2005-2010. Kidney function, based on glomerular filtration rate (GFR), calculated by the simplified modification in diet in renal disease (MDRD) equation (sMDRD); troponin I; B-type natriuretic peptide (BNP); and echocardiographic markers of right ventricular (RV) function were determined in survivors versus non-survivors after a 2-year follow-up. RESULTS: GFR was significantly lower in non-survivors than in survivors: 51.85±19.08 mL/min/1.73 m2 and 71.65±23.21 mL/min/1.73 m2, respectively (p=0.000). The highest 2-year mortality rate (20%) was recorded in patients with moderate renal dysfunction associated with RV dysfunction. Using multivariate analysis, we found that GFR is an independent predictor of 2-year mortality (OR 0.973, 95% CI: 0.959-0.987, p=0.000), besides troponin I, dyslipidemia, acceleration time of pulmonary ejection, pericardial effusion, and BNP. CONCLUSION: The association of renal dysfunction with right ventricular dysfunction in patients with non-fatal pulmonary thromboembolism resulted in high mortality. Renal dysfunction, assessed by glomerular filtration rate, may be used in the risk stratification of patients with non-high-risk pulmonary thromboembolism, besides troponin I, BNP, and right ventricle echocardiographic dysfunction markers.

Atrial Fibrillation and Gastro-Oesophageal Reflux Disease - Controversies and Challenges.

Atrial fibrillation and gastro-oesophageal reflux are common manifestations in daily practice. The atria and the oesophagus are closely located and have similar nerve innervations. Over the last years, it has been observed that atrial fibrillation development and reflux disease could be related. Atrial fibrillation occurrence could be due to vagal nerve overstimulation. This, in association with vagal nerve-mediated parasympathetic stimulation, has also been observed in patients with gastro-oesophageal reflux. These mechanisms, in addition to inflammation, seem to be implicated in the pathophysiology of both diseases. Despite these associations supported by clinical and experimental studies, this relationship is still considered controversial. This review summarizes critical data regarding the association of gastro-oesophageal reflux and atrial fibrillation as well as their clinical implications.

Polymorphic ventricular tachycardia in acute myocardial infarction treated by thrombolysis: reperfusion, complication or iatrogenic sign?

The QT interval prolongation may determine a type of polymorphic ventricular tachycardia named torsades de pointes. This ventricular arrhythmia could also appear after thrombolysis of acute myocardial infarction.Case reports. A 57 years old man was admitted 2 hours after the onset of a posterior-inferior-lateral acute myocardial infarction (reinfarction). He underwent pharmacological revascularization with reteplase. In the first 24 hours after thrombolysis a sustained polymorphic ventricular tachycardia was unregistered after the second dose of a quinolone recommended for a urological problem. Despite of the normal serum potassium and magnesium QTc suffered an augmentation from 400 ms to 480 ms. After beta-blocker augmentation dose and the antibiotic changing, ventricular arrhythmia disappeared without repetition during hospitalization. This ventricular tachycardia was considered precipitated by the quinolones therapy by increasing of QTc interval. It could also be considered a reperfusion sign or a complication of the reinfarction in the same area, which means different therapeutical solutions.

Assessment of left atrial shape and volume in structural remodeling secondary to atrial fibrillation.

PURPOSE: Assessment of volume in relation with left atrial (LA) shape alteration before and after PV isolation. METHODS: We compared trapezoidal modification of LA using echocardiography with the ellipsoid formula (EEL: ) and CT, with both ellipsoid (CTEL: ) and truncated cone formulas (CTTR: ), in 40 patients, before and +/-3 months after AF ablation. RESULTS: A trapezoidal shape was present in 76.3% of patients. The different volume measurements were statistically correlated (r = 0.603-0.837, p < 0.001) irrespective of the formula used. After reverse remodeling, with 77.5% of patients in stable sinus rhythm, correlation coefficient for volume remained significant (p < 0.001). CONCLUSIONS: In AF, dilation of the LA is associated with a geometrical trapezoidal change in many cases. The CT truncated cone formula applies best for precise evaluation of trapezoidal shape alteration in dilated AF atria. There is a good correlation between CTTR: and echocardiography which remains a valuable estimation for volume calculation in clinical practice.