Complete atrioventricular block is a relatively uncommon arrhythmia that is nonetheless increasingly seen in elderly people of developed countries, due to the increase in life expectancy. Congenital and degenerative etiologies are the most commonly seen among young and old patients, respectively. However, scientific literature is surprisingly scarce regarding the etiology of complete atrioventricular block in the asymptomatic otherwise healthy young and middle-aged adult population. Coronary artery disease, autoimmune disorders such as systemic lupus erythematosus or rheumatoid arthritis, history of acute or chronic infectious or hypersensitivity myocarditis, infiltrative processes, hypothyroidism, congenital cardiopathies such as left ventricular noncompaction or Ebstein anomaly, lamin A/C mutations, and pathologic hypervagotony and idiopathic degenerative scleroatrophy of the atrioventricular junctional specialized tissue (Lenegre-Lev disease) are among the most frequent etiologies of complete atrioventricular block in young or middle-aged adults. To our knowledge, no comprehensive review on the specificities of the investigation warranted in this age group has ever been developed, nor have the implications of particular diagnoses on treatment modalities been appropriately addressed. We aim at reviewing the most frequent differential diagnoses of advanced atrioventricular block in otherwise healthy asymptomatic or mildly symptomatic young or middle-aged adults and their impact on therapeutic options. Additionally, we suggest a diagnostic algorithm that may be helpful in this group of patients. (PACE 2012; 35:1395-1405) complete atrioventricular block, atrioventricular block etiology, cardiac conduction Introduction Complete heart block, also referred to as third-degree heart block or third-degree atrioventricular (AV) block, is a disorder of the cardiac conduction system where there is complete dissociation of the atrial and ventricular activity due to the absence of conduction through the atrioventricular node (AVN) or His-Purkinje system. Although Mobitz I second-degree AV block is observed in 1-2% of healthy young people, especially during sleep, the prevalence of third-degree AV block is only 0.02% in the United States and 0.04% worldwide. 1,2 Its incidence increases with advancing age (highest in people older than 70 years), despite an early peak in infancy and early childhood due to congenital

The presence of AF, irrespective of its timing, may independently predict mortality in patients with acute PE. These data should be tested and validated in prospective studies using larger cohorts.

Background: It is currently unknown if the increased risk of stroke in subjects with chronic kidney disease and atrial fibrillation (AF) is due to the presence of left atrial stasis or to any other vascular or systemic conditions. Methods: This was a retrospective study of 372 subjects undergoing evaluation during an AF episode. The following markers of left atrial stasis were sought on transesophageal echocardiogram: left atrial or left atrial appendage thrombus (LAAT), dense spontaneous echocardiographic contrast (DSEC), and low flow velocities (LFV) in the left atrial appendage. Subgroup comparisons were performed according to the level of estimated glomerular filtration rate (eGFR) using the Chronic Kidney Disease Epidemiology Collaboration equation as follows: ≥90, 45–89.9, and <45 ml/min/1.73 m². Results: LAAT was found in 11.6%, DSEC in 29.0%, and LFV in 14.9% of cases. A significant increase in the prevalence of DSEC was observed in the lower categories of eGFR: 37.8% in eGFR <45 ml/min, 30.7% in eGFR 45–89.9 ml/min, and 17.0% in eGFR ≥90 ml/min (p = 0.009; γ for trend = 0.297, p = 0.002). The same was observed when assessing left atrial abnormality, i.e. the presence of at least one of the former transesophageal echocardiogram changes. On multivariate analysis, clinical parameters from CHADS₂ (congestive heart failure, hypertension, age ≥75, diabetes mellitus and stroke) and CHA₂DS₂-VASc (age 65–74, history of vascular disease, and female gender along with the clinical variables from CHADS₂) were predictors of transesophageal echocardiogram changes and an additive predictive value was found for eGFR. Conclusions: Our results suggest an association between compromised renal function as assessed through eGFR and markers of left atrial stasis in patients with AF. The increased risk of stroke in this population may be due to thromboembolism.

Age is an adverse prognostic factor in patients with heart failure. We aimed to assess the impact of age and noncardiac co-morbidities in the outcome of patients undergoing cardiac resynchronization therapy (CRT), and determine which of these two factors is the most important predictor of survival. The study involved a single-center retrospective assessment of 697 consecutive CRT implants during a 12-year period. Patient co-morbidity profile was assessed using the Charlson Co-morbidity Index (CCI) and the Charlson Age-Co-morbidity Index (CACI). Predictors of survival free from heart transplantation were assessed. CRT-related complications and cause of death analysis were assessed within tertiles of the CACI. During a mean follow-up of 1,813 ± 1,177 days, 347 patients (49.9%) died and 37 (5.3%) underwent heart transplantation. On multivariate Cox regression, female gender (HR = 0.78, 95% confidence interval [CI] 0.62 to 0.99, p = 0.041), estimated glomerular filtration rate (HR per ml/min = 0.99, 95% CI 0.98 to 0.99, p < 0.001), left ventricular ejection fraction (HR per % = 0.99, 95% CI 0.98 to 1.00, p = 0.022), New York Heart Association class (HR = 1.83, 95% CI 1.53 to 2.20, p < 0.001), presence of left bundle branch block (HR = 0.70, 95% CI 0.56 to 0.87, p = 0.001), and CACI tertile (HR = 1.37, 95% CI 1.18 to 1.59, p < 0.001) were independent predictors of all-cause mortality or heart transplantation. Compared with age and the CCI, the CACI was the best discriminator of all-cause mortality. Inappropriate therapies occurred less frequently in higher co-morbidity tertiles. In conclusion, patient co-morbidity profile adjusted to age impacts on mortality after CRT implantation. Use of the CACI may help refine guideline criteria to identify patients more likely to benefit from CRT.

GRACE score for IHM, GFR and admission haemoglobin independently predicted risk for pre-discharge MR. MR, including its milder form, was an independent predictor of 2-year mortality, adding prognostic power to GRACE score.