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mean ejection fraction than the controls. The mean fractional shortening was significantly lower in the patients than in controls. Eleven (12.2%) of the patients and two (2.2%) controls had abnormal fractional shortening. Diastolic dysfunction was found in 65.6% of patients compared to 3.3% of controls. Fifty two (57.8%) patients and three (3.3%) controls had an impaired relaxation. Six (6.7%) patients and one (1.1%) control had a pseudo normal filling pattern. A restrictive pattern was seen in one patient but none in the controls. The left ventricular mass index (LVMI) was higher in patients than in the controls.
3.7 RELATIONSHIP BETWEEN LEFT VENTRICULAR FUNCTION AND
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Fiorina et al65 using radionuclide ventriculography, in 68 uraemic type 1 diabetics (42 kidney-pancreas transplant patients and 26 kidney-alone recipients) and 20 type 1 diabetics (control) found normal left ventricular ejection fraction in all of the patients. However, kidney-pancreas transplant patients with 4 years of graft function had a higher ejection fraction than kidney-alone patients with 4 years of graft function and type 1 diabetic patients.
In patients with 4 years of graft function, normal diastolic parameters were evident in kidney-pancreas but not in kidney-alone or in type 1 diabetic patients. A significant reduction in diastolic dysfunction rate was observed only in kidney-pancreas patients. This improvement of LV diastolic function is thought to be positively associated with glycaemic control.
Hiramatsu et al66 evaluated 48 T2DM patients using Doppler echocardiography at baseline, 1 month and 6 months following intensive glycaemic control using insulin. The Isovolumic relaxation time was significantly greater while the E/A was significantly lower in diabetic patients than in age- and sex-matched control subjects at baseline. Improvement in diastolic function was noticed at 1 month and was maintained at 6 months following intensive glycaemic control only in those diabetics without retinopathy.
Vanninen et al67 using M-mode and Doppler echocardiography assessed LV function in 26 men and 17 women with newly diagnosed non-insulin-dependent diabetes mellitus, and in 13 healthy control men and 13 women. The diabetic men had lower peak filling rate normalized to mitral stroke volume than the control men. The diabetic women had decreased fractional shortening when compared with control women. At 3 and 15 months, 23 diabetic men and 15 women were re-examined. With decreasing blood glucose levels, fractional shortening improved mainly during the first 3 months and was significantly higher in both diabetic men and women at 15 months than at baseline. In the diabetic men, peak filling rate was significantly higher at 15 months compared to baseline. They found an improvement of diastolic as well systolic function evaluated after a 15-month period in a population of newly
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diagnosed type 2 diabetic patients (n= 43) which corresponded with declining blood glucose levels .
Hirayama et al68 in a study conducted among a population of 22 type 2 diabetics (10 hypertensive and 12 normotensive) all of whom had been diagnosed for over 10 years, using Doppler echocardiography to evaluate the effect of improved glycaemic control on LV function after a 6-month period demonstrated an improvement in diastolic function among normotensive patients (n = 12) following treatment, but not in the hypertensive patients.
Punzengruber et al69 , using echophonocardiography studied 50 fairly well-controlled young type 1 diabetics (mean age 26 ± 7.9 years) 50 age- and sex-matched controls. Type 1 diabetics did not differ from controls in their ratio of pre-ejection period to left ventricular ejection time and systolic shortening fraction. However, Isovolumetric relaxation period (reflecting an early diastolic event) was slightly but significantly prolonged in diabetic subjects, independent of metabolic control status or existence of early microangiopathy. They did not find any relationship between glycaemic control over a period of 12 months and LV diastolic function.
Gough et al70 assessed left ventricular diastolic function using Doppler echocardiography in 20 normotensive patients with a new diagnosis of type 2 diabetes mellitus, normal cardiac function and no evidence of coronary artery disease and in 16 age-matched normal subjects.
Peak velocities of early (E) and late (A) left ventricular filling were measured. The median peak E/A ratio was significantly reduced in the diabetic group at baseline. Despite improvements in glycaemic control at 3 months and at 6 months compared to baseline, there were no changes in the E/A ratio. They concluded that in patients with type 2 diabetes mellitus and normal systolic function, who had impaired diastolic function at diagnosis there was no improvement in diastolic function despite an improved glycaemic control.
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Beljic et al71 evaluated left ventricular diastolic function in ten newly diagnosed type 2 diabetes patients by Doppler echocardiography, performed at the onset of disease and after 6 and 12 months of adequate glycaemic control. The control group consisted of ten healthy subjects of matching age and body mass index. The following parameters of left ventricular function were evaluated: ejection fraction (EF), peak velocity of the early (E) and late atrial (A) mitral flow, A/E ratio, duration of the early (E) and of the atrial (A) filling phase. A significantly shorter duration of E, a higher value of A, and lower E/A were found in the diabetic patients before treatment. The parameters did not significantly change after 1 year of adequate glycaemic control. They concluded that a left ventricular filling abnormality is present in newly diagnosed non-insulin-dependent diabetic patients and does not reverse with improved glycaemic control.
Pitale et al72 in the Veterans Affairs Cooperative Study in Type 2 Diabetes Mellitus (VA CSDM) a multicenter randomized prospective study of 153 male type 2 diabetic patients evaluated the effect of 2 years of intensive glycaemic control on left ventricular (LV) function. The patients were randomized to intensive step treatment with insulin alone or with sulfonylurea (intensive treatment arm [INT], n = 75) or to standard once-daily insulin injection (standard treatment arm [STD], n = 78) treatment. A total of 136 patients (STD, n = 70; INT, n = 66) had radionuclide ventriculography at entry and at 24 months for the assessment of LV function. They found no difference in the mean LV ejection fraction, peak filling rate and time to peak filling rate between the 2 treatment arms. They concluded that two years of intensive glycaemic control did not affect the LV systolic or diastolic function in patients with type 2 diabetes.
Patil et al62 in a case- control study involving 127 subjects with type 2 diabetes mellitus which utilized echocardiography found that out of 89 subjects with HbA1c < 7.5%, 39 (42.82%) had diastolic dysfunction, while out of 38 subjects with HbA1c > 7.5%, 31
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(81.57%) had diastolic dysfunction. Subjects with HBA1c > 7.5% had more prevalence of diastolic dysfunction, than subjects with HBA1c < 7.5%.
3.8 RELATIONSHIP BETWEEN LEFT VENTRICULAR FUNCTION AND