Valor prognóstico da incompetência cronotrópica em idosos diabéticos

• Autor(a) principal: Santana, Juliana Silva
• Data de Publicação: 2012
• Tipo de documento: Dissertação
• Idioma: por
• Título da fonte: Repositório Institucional da UFS
• Texto Completo: https://ri.ufs.br/handle/riufs/3775
• topic: Diabetes mellitus; Ecocardiograma; Idoso; Incompetência cronotrópica; Chronotropic incompetence; Elderly; Echocardiography; CNPQ::CIENCIAS DA SAUDE

Background: The world population aging is evident and as a consequence, there is an increase of chronic diseases prevalence such as diabetes mellitus (DM) and cardiovascular diseases. The latter represent the main cause of death in elderly, especially coronary artery disease (CAD) and stroke. The chronotropic incompetence (CI) is characterized by an attenuated heart rate response to exercise. It represents a predictor of mortality and adverse cardiovascular events, and is defined as the failure to achieve less than 80% of heart rate reserve. However, its physiopathological mechanisms have not been clearly defined. One of the hypothesis postulates that it represents an abnormality in cardiovascular autonomic control. The DM and its chronic complications, such as autonomic neuropathy, are independent risk factors for stroke. As a possible manifestation of autonomic dysfunction, CI may be useful for cardiovascular risk stratification in diabetic patients. Objective: Estimate the value of chronotropic incompetence for predicting stroke in elderly diabetic patients that were submitted to exercise stress echocardiography, events included acute myocardial infarction (AMI), stroke and death. Methods: This was a restrospective observational H that assessed 298 elderly diabetic patients (from a population of 8269). Exercise stress echocardiography was performed by all participants of the study from January, 2000 to December, 2010. After exclusion criteria, patients were divided into two groups: G1 (patients who failed to achieve 80% of the age-predicted chronotropic index during exercise echocardiography) and G2 (patients who were able to achieve 80% of the age-predicted chronotropic index during exercise echocardiography). Results: There were 109 (36,6%) patients with chronotropic incompetence. Concerning clinical features, there were differences between the groups with reference to male gender (p=0,01), previous dyspneia (p=0,02) and typical angina. Concerning exercise stress echocardiography variables, there were divergences between groups for WMSI at rest, WMSI after exercise, LV mass index and LA diameter. In relation to cardiovascular events, the G1 group presented stroke in a higher frequency (9,2 % vs. 3,2%; p= 0,27) with relative risk 2,89 and G1 95% 1,05 - 7,95. The CI group presented higher frequency of death in patients that had AMI (p =0, 015) and stroke (p =0, 004). Conclusion: Our data suggest that CI predicts a worse prognosis for the occurrence of stroke in elderly diabetics as well as mortality for patients who developed with stroke and AMI.