Prevalence of left ventricular diastolic dysfunction by cardiac magnetic resonance imaging in thalassemia major patients with normal left ventricular systolic function.

BACKGROUND: The leading cause of mortality of thalassemia major patients is iron overload cardiomyopathy. Early diagnosis with searching for left ventricular diastolic dysfunction before the systolic dysfunction ensued might yield better prognosis. This study aimed to define the prevalence of the left ventricular diastolic dysfunction (LVDD) in thalassemia major patients with normal left ventricular systolic function and the associated factors. METHODS: Adult thalassemia major patients with normal left ventricular systolic function who were referred for cardiac T2* at Siriraj Hospital - Thailand's largest national tertiary referral center - during the October 2014 to January 2017 study period. Left ventricular diastolic function was defined by mitral valve filling parameters and left atrial volume index using CMR. Patients with moderate to severe valvular heart disease, pericardial disease, or incomplete data were excluded. Baseline characteristics, comorbid diseases, current medication, and laboratory results were recorded and analyzed. RESULTS: One hundred and sixteen patients were included, with a mean age of 27.5 ± 13.5 years, 57.8% were female, and 87.9% were transfusion dependent. Proportions of homozygous beta-thalassemia and beta-thalassemia hemoglobin E were 12.1 and 87.9%, respectively. The baseline hematocrit was 26.3 ± 3.3%. The prevalence of LVDD was 20.7% (95% CI: 13.7-29.2%). Cardiac T2* was abnormal in 7.8% (95% CI: 3.6-14.2%). Multivariate analysis revealed age, body surface area, homozygous beta-thalassemia, splenectomy, heart rate, and diastolic blood pressure to be significantly associated with LVDD. CONCLUSIONS: LVDD already exists from the early stages of the disease before the abnormal heart T2 * is detected. Homozygous beta-thalassemia and splenectomy were strong predictors of LVDD. These data may increase awareness of the disease, especially in the high risk groups.

Prevalence and Factors Associated with Left Ventricular Systolic Dysfunction in End-Stage Renal Disease Patients on Dialysis.

Background: Heart failure is a major cause of morbidity and mortality in patients with end-stage renal disease (ESRD). Previous studies reported various factors associated with left ventricular systolic dysfunction (LVSD) in patients with ESRD. Objective: To investigate the prevalence and factors associated with LVSD in patients with ESRD on dialysis. Material and Method: Patients with ESRD on dialysis who underwent comprehensive transthoracic echocardiography at Siriraj Hospital between 2003 and 2014 were enrolled. LVSD was defined as left ventricular ejection fraction less than 40%. Results: One hundred sixty one patients with a mean age of 56.5±15.4 years were included and 46% were female. Regarding mode of dialysis, 25% and 75% of patients were on peritoneal dialysis and hemodialysis, respectively. Median duration of dialysis was three years. Smoking, diabetes, dyslipidemia, and hypertension were reported in 30%, 40%, 57%, and 94% of patients, respectively. History of heart failure and coronary artery disease (CAD) were reported in 23% and 24% of cases, respectively. Prevalence of LVSD was 5%. History of heart failure, known CAD, and left ventricular diastolic dimension (LVDd) were found to be univariately associated with LVSD. Multivariate factors associated with LVSD were known CAD (OR 23.67, 95% CI 1.23-456.54, p-value = 0.036) and LVDd (OR 1.56, 95% CI 1.15-2.11, p-value = 0.004). Conclusion: Prevalence of LVSD in patients with ESRD on dialysis in the present study was 5%. Known CAD and LVDd were independent predictors of LVSD in this population.