Right ventricular function in systemic sclerosis, relation to ICAM-1

Background: Cardiopulmonary involvement in patients with systemic sclerosis [SSc] carries a poor prognosis mainly due to pulmonary hypertension and right-heart failure. The early detection of right ventricle [RV] dysfunction may be important when assessing the prognosis and optimizing treatment. The study aimed to investigate earlier detection of right ventricular dysfunction in systemic sclerosis patients and investigate a possible role of intercellular adhesion molecule-1 [ICAM-1] to a such condition

Methods: The study included 23 SSc patients [mean age 45.4 +/- 10.9 years and disease duration 8.6 +/- 7.5 years] and 21 healthy age and sexmatched control subjects. Doppler echocardiography was used to evaluate cardiac function, high resolution CT to evaluate lung fibrosis. ICAM-1 levels was measured for patients as well as healthy control subjects

Results: An abnormal right ventricular function was established by SSc patients group by higher right ventricle myocardial performance index [RVMPI], lower fractional area shortening [FAS], decreased tricuspid valve E/A ratio, prolonged tricuspid valve deceleration time [TV DT], prolonged right ventricle isovolumic relaxation time [RV IVRT], reduced tricuspid valve filling time corrected to heart rate [0.303 +/- 0.031 vs 0.285 +/- 0.004, P=0.01 and 39.01 +/- 4.2vs 43.3 +/- 5.01, P=0.004 and 0.93 +/- 0.17, 1.03 +/- 0.19, P=0.02 and 191.1 +/- 24.9ms vs 172.4 +/- 28 ms, P=0.002, 60 +/- 23 ms vs 46 +/- 15ms, P=0.02 and 50 +/- 7ms vs 54 +/- 4.1 ms, P=0.02] respectively. These findings were associated with higher ICAM-1 levels in patients than control [468.8 +/- 77 vs 289 +/- 89, P<0.001] as well as higher pulmonary artery systolic pressure [PASP] in SSc patients than controls [38.56 +/- 9.7 mmHg vs 31.2 +/- 8.5 mmHg, P=0.02]. The subgroup of SSc patients [n=11] with stronger evidence of right ventricular systolic and diastolic dysfunction had significantly higher ICAM levels and higher PASP [0.324 +/- 0.03 ng/ml vs 0.286 +/- 0.0024 ng/ml, P<0.001 and 47 +/- 7.36 mmHg vs 30.8 +/- 2.24 mmHg, P<0.001] respectively. Moreover, ICAM-1 correlated significantly with RVMPI, RV FAS, TV E/A ratio, RV IVRT as well as PASP [P=0.004 and 0.032 and0.017 and 0.001 and 0.025] respectively. Also, higher ICAM-levels were associated with increased relative risk of valvular lesion, pulmonary hypertension, lung fibrosis, more advanced LV diastolic dysfunction, joint, muscle and gastrointestinal affection in the studied SSc patients

Conclusion: Altered right ventricular function is exhibited by a considerable percentage of SSc patients. Such alteration is detectable in patients without any clear cut evidence of cardiac disease. Such alteration could be adequately estimated by echo Doppler. Myocardial performance index could be a useful tool. sICAM-1 levels may reflect the extent of right ventricular involvement in SSc patients and point to a pathogenic role of adhesion molecules in systemic manifestation of the disease

effect of acute hyperglycaemia on QTc and QTc dispersion in healthy subjects

The QTc prolongation is a condition that predisposes for cardiac arrhythmias and is associated with a high mortality even in apparently healthy population. The aim of the study was to investigate the effect of acute hyperglycaemia on QTc, QTc dispersion in healthy subjects. 20 healthy subjects [10 males and 10 female] underwent hyperglycaemic clamp by quickly raising plasma glucose concentration to 270 mg/dl and maintaining this level for 2 hours. The same subjects, on another occasion, underwent the same hyperglycaemia clamp with octreotidesomatostatin analogue-infusion to block the release of endogenous insulin. Systolic and diastolic blood pressure, heart rate plasma, catecholamine concentrations, QTc and QTc dispersion showed significant increase at 120 minutes of the hyperglycaemic clamp. Octreotide infusion did not influence QTc duration. QTc dispersion and the haemodynamic effects of acute hyperglycaemia. Our results confirm that acute hyperglycaemia produces significant increments of QTc and QTc dispersion in normal subjects and endogenously released insulin is suggested to have no significant or pivotal role