Added value of cardiac deformation imaging in differential diagnosis of left ventricular hypertrophy

Global longitudinal strain predicts atrial fibrillation in individuals without hypertension: A Community-based cohort study

BACKGROUND

Global longitudinal strain (GLS) is a sensitive marker of myocardial dysfunction and atrial reservoir function. We sought to evaluate its value for predicting atrial fibrillation (AF) in the general population.

METHODS

Participants from the Copenhagen City Heart Study examined with echocardiography, including speckle tracking analyses, were included. The endpoint was AF obtained through national registries. Proportional hazards Cox regression was applied, including multivariable adjustments made for CHADS₂ and CHARGE-AF risk factors. Abnormal GLS was defined as >-18%.

RESULTS

The data from 1,309 participants were analyzed. Of those, 153 (12%) developed AF during a median follow-up time of 15.9 years. The follow-up was 100%. The mean age was 57 years, 38% had hypertension, and GLS was  - 18%. In unadjusted analysis, GLS was a univariable predictor of outcome (1.08 (1.04-1.13), p < 0.001, per 1% absolute decrease), but did not remain an independent predictor after adjusting for neither CHADS₂ nor CHARGE-AF risk factors. However, hypertension modified the relationship between GLS and AF (p for interaction = 0.010), such that GLS only predicted AF in subjects without hypertension. In participants without hypertension, GLS remained an independent predictor of AF after adjusting for CHADS₂ and CHARGE-AF (HR = 1.11 (1.03-1.20) and HR = 1.09 (1.01-1.19), respectively). In these participants, an abnormal GLS was associated with a more than twofold increased risk of AF (HR = 2.16 (1.26-3.72). The incidence rate was 3.17 and 6.81 per 1000 person-years for normal vs. abnormal GLS, respectively.

CONCLUSION

Global longitudinal strain predicts AF in individuals without hypertension from the general population, independently of common risk scores.

Involvement of the Areae Compositae of the Heart in Endemic Pemphigus Foliaceus

Background

A new variant of endemic pemphigus foliaceus in El Bagre (El Bagre-EPF), Colombia, South America, shares features with Senear-Usher syndrome and occurs in an endemic fashion. Patients affected by El Bagre-EPF have heterogeneous antigenic reactivity not only to the skin but to other organs, including the heart. Here we test for autoantibodies to the areae compositae of the heart (structure consisting of typical desmosomal amalgamated fascia adherens molecules) and evaluate any possible clinical correlation.

Methods

A case-control study comparing 45 patients and 45 controls from the endemic area, matched by demographics including age, gender, weight, work activities, and comorbidities, was performed. Direct and indirect immunofluorescence, immunohistochemistry, confocal microscopic studies, and echocardiogram studies were completed.

Results

The main clinical abnormally seen in the El Bagre-EPF patients was left ventricular hypertrophy in 15/45 patients, compared with no such findings in the control population (P < 0.1). Seventy percent of El Bagre-EPF patients and none of the controls displayed polyclonal autoreactivity using different immunoglobulins and complement to the areae compositae of the heart using different methods and antibodies (P < 0.1).

Conclusions

Patients affected by El Bagre-EPF demonstrated autoantibodies to the areae compositae of the heart. This finding was associated with left ventricular hypertrophic cardiomyopathy. The areae compositae may play a role in cell junction tension and the El Bagre-EPF patients' autoantibodies possibly disrupting these junctions and thereby contributing to the left ventricular hypertrophy.