Atrial conduction times and left atrium mechanical functions in patients with active acromegaly

Myocardial, Valvular, and Vascular Structural and Functional Properties in Acromegaly

Acromegaly is an uncommon systematic endocrine disease caused by the hypersecretion of human growth hormone and, consequently, of insulin-like growth factor-1 during adulthood. Acromegaly could cause a typical cardiomyopathy characterized by left ventricular hypertrophy associated with diastolic dysfunction, which later could progress to systolic dysfunction. Moreover, some valvular and vascular abnormalities are also associated with acromegaly. This present review aims to summarize available information regarding acromegaly-associated abnormalities in myocardial, valvular, and vascular structural and functional properties and their relationship to disease activity and treatment options.

Disfunção Ventricular e do Átrio Esquerdo Subclínica em Pacientes com Acromegalia: Um Estudo de Ecocardiograma de Rastreamento de Manchas

Fundamento

Embora se saiba que a fração de ejeção (FE) do ventrículo esquerdo (VE) medida por eletrocardiograma seja preservada em pacientes com acromegalia, não há informação suficiente sobre deformação longitudinal global e deformação do átrio esquerdo (SLG-VE e SAE).

Objetivo

O objetivo deste estudo foi avaliar as funções do ventrículo esquerdo (VE) e do átrio esquerdo (AE) por ecocardiograma strain (ES) em pacientes com acromegalia.

Métodos

Este estudo incluiu 50 pacientes com acromegalia na forma ativa da doença e 50 controles saudáveis com idade, sexo e área de superfície corporal similares. Além dos ecocardiogramas de rotina, medições de SLG-VE e SAE foram realizadas com o ES.

Resultados

Os valores dos SAE e SLG-VE foram significativamente mais baixos em pacientes com acromegalia (p<0,05 para todos). Na análise bivariada, a pressão arterial sistólica, o pró-hormônio N-terminal do peptídeo natriurético cerebral, o fator de crescimento semelhante à insulina tipo 1, e detectou-se que os níveis de IMVE tinham correlação positiva com SAE e SLG-VE (p<0,05). O nível de IGF-1 tinha forte correlação com SAE e SLG-VE (p<0,001 e β=0,5 vs. p<0,001 e β=0,626, respectivamente); 48% dos pacientes com acromegalia têm SLG-VE reduzido (<20%). O índice de massa do ventrículo esquerdo (IMVE) determina independentemente a presença de SLG-VE reduzido, e cada 1g/m² de aumento no nível de IMVE aumenta a probabilidade de redução de SLG-VE em 6%.

Conclusão

Embora a fração de ejeção de VE seja normal em pacientes com acromegalia, os valores de SAE e SLG-VE são significativamente mais baixos. Além do aumento em IMVE, outro achado do envolvimento cardíaco pode ser a redução de SAE e SLG-VE. Portanto, além do ecocardiograma de rotina, SAE e SLG-VE podem ser úteis para avaliar os sinais iniciais de envolvimento cardíaco antes da ocorrência de alterações cardíacas irreversíveis.

Evaluation of atrial fibrillation risk in patients with vasovagal syncope

BACKGROUND

This study aimed to determine whether autonomic dysfunction in patients with vasovagal syncope with a positive tilt test may cause an alteration in atrial electromechanical properties and pose a risk for subsequent atrial arrhythmias, especially atrial fibrillation.

METHODS

The data of 27 patients with vasovagal syncope and a matched control group comprising 28 healthy individuals were compared. All patients underwent a tilt table test. Atrial electromechanical intervals (PA) were measured from the mitral lateral annulus, mitral septal annulus, and tricuspid annulus with tissue Doppler imaging. Left atrium volumes were measured with the disc method in apical four-chamber imaging.

RESULTS

Although atrial electromechanical intervals such as lateral PA, septal PA, and tricuspid PA durations were significantly longer (p = 0.009, p = 0.002, p = 0.011, respectively), interatrial, right intra-atrial, and left intra-atrial durations were similar in the vasovagal syncope group and the control group (p = 0.298, p = 0.388, p = 0.069, respectively). Left atrial volumes (maximum, minimum, and presystolic) were significantly increased in the vasovagal syncope group when compared with the control group (p = 0.001, p = 0.001, p = 0.007, respectively). There was no difference between vasovagal syncope types in terms of atrial electromechanical intervals.

CONCLUSION

Interatrial and intra-atrial intervals were similar in the vasovagal syncope group and the control group. However, an increase in atrial volumes and a prolongation of certain atrial electromechanical intervals were observed in patients with vasovagal syncope. These findings suggest an alteration in atrial electromechanics caused by autonomic dysfunction that can lead to subsequent atrial arrhythmias, especially atrial fibrillation.

Usefulness of tissue Doppler-derived atrial electromechanical delay for identifying patients with paroxysmal atrial fibrillation

Background

Tissue Doppler imaging (TDI)-derived atrial electromechanical delay (AEMD) has been reported to be useful for detecting paroxysmal atrial fibrillation (PAF). However, its usefulness remains unknown when analyzed along with patients seemingly at high-risk for AF as controls. From this standpoint, we investigated whether AEMD would be of use for identifying patients with PAF.

Methods

We retrospectively analyzed TDI recordings to obtain AEMD in 63 PAF patients. Thirty-three patients with multiple cardiovascular risk factors (MRFs) but without history of AF and 50 healthy individuals served as disease and healthy controls, respectively. AEMD was defined as the time-interval between the electrocardiogram P-wave and the beginning of the spectral TDI-derived A’ for the septal (septal EMD) and lateral (lateral EMD) sides of the mitral annulus.

Results

There was no significant difference in the left atrial volume index between PAF patients and disease controls (28 ± 9 mL/m² vs. 27 ± 5 mL/m²). PAF patients had longer AEMD, particularly for the lateral EMD (75 ± 23 ms), compared with disease (62 ± 22 ms, P = 0.009) and healthy (54 ± 24 ms, P < 0.001) controls. Multivariate logistic regression analysis revealed that the lateral EMD (OR 1.25, 95%CI 1.03–1.52, P = 0.023), along with the left atrial volume index (OR 2.25, 95%CI 1.44–3.51, P < 0.001), was one of the significant independent associates of identifying PAF patients.

Conclusions

This cross-sectional study indicates that even analyzed together with MRFs patients, AEMD remains useful for identifying patients at risk for AF. Our results need to be confirmed by a large-scale prospective study.

Systemic Complications of Acromegaly and the Impact of the Current Treatment Landscape: An Update

Acromegaly is a chronic systemic disease with many complications and is associated with increased mortality when not adequately treated. Substantial advances in acromegaly treatment, as well as in the treatment of many of its complications, mainly diabetes mellitus, heart failure, and arterial hypertension, were achieved in the last decades. These developments allowed change in both prevalence and severity of some acromegaly complications and furthermore resulted in a reduction of mortality. Currently, mortality seems to be similar to the general population in adequately treated patients with acromegaly. In this review, we update the knowledge in complications of acromegaly and detail the effects of different acromegaly treatment options on these complications. Incidence of mortality, its correlation with GH (cumulative exposure vs last value), and IGF-I levels and the shift in the main cause of mortality in patients with acromegaly are also addressed.