Higher red cell distribution width values are associated with impaired exercise capacity during exercise treadmill testing in patients without obstructive coronary disease: a preliminary study.

BACKGROUND: Red cell distribution width (RDW) is associated with poor cardiovascular outcomes. We aimed to find out if this association could be explained by impaired exercise capacity in patients without obstructive coronary artery disease (CAD). PATIENTS AND METHODS: The patients who underwent exercise treadmill test (ETT) who have non-obstructive CAD and were free of heart failure symptoms were evaluated. Total of 132 patients were enrolled, and patients were divided into three groups according to their Metabolic Equivalent Task (MET) level measured by exercise treadmill test (ETT): Less than 7 METs (group 1), 7-10 METs (group 2) and greater than 10 METs (group 3). RESULTS: The patients in Group 1 had significantly higher RDW levels (16.46 ± 2.79) compared to Group 2 (15.05 ± 2.03) and Group 3 (14.52 ± 1.37), independent of hemoglobin and hematocrit values. Significant differences for age, gender, duration of ETT and Duke Treadmill Score were also found in proportion to the reduced exercise capacity. In multivariate analysis, only duration of ETT (ß = 1.017, p = < 0.001) and RDW (ß = 0.040, p = 0.026) were found as independent variables, which had statistically significant effects on METs. CONCLUSIONS: We found an independent association between RDW and exercise capacity in patients free of obstructive coronary disease suggesting that patients with elevated RDW values are expected to have impaired exercise capacity.

Increased sympathetic activation in patients with vasovagal syncope is associated with higher mean platelet volume levels.

OBJECTIVES: Vasovagal syncope (VVS) is supposed to be modulated by increased sympathetic tone following an orthostatic maneuver. Increased sympathetic activity may have an important role in mean platelet volume (MPV), either by peripheral activation or by effects on thrombocytopoiesis. We aimed to show the effects of increased sympathetic activity on platelet size in patients with VVS in the present study. PATIENTS AND METHODS: Thirty-seven patients with VVS were compared with age- and sex-matched 33 patients without VVS. All patients have undergone 24 hour holter monitoring for heart rate variability (HRV) and time-domain HRV analysis. Blood samples for MPV measurements were taken before 24 hour holter monitoring. RESULTS: Group 1 was consisted of 37 patients with VVS and group 2 was consisted of 33 patients without VVS. We observed that SDNN, SDNN index, SDSD, RMSDD, PNN50 count were significantly lower and MPV was found significantly higher in patients with VVS (p < 0.05 for all). Pearson's correlation analysis showed that MPV was moderately negatively correlated with SDNN (r = -0.421), SDSD (r = -0.396), NN50 count (r = -0.395) and RMSDD (r = -0.393). Multivariate regression analysis showed that SDNN was the only independent variable, which had a significant effect on increased MPV level (ß = -0.295 , p = 0.016). CONCLUSIONS: We found that MPV was closely associated with increased sympathetic activity in patients with VVS. Our analysis supports the hypothesis that alterations in autonomic status might play a role in the development of platelet size.

Bilateral coronary-pulmonary artery fistulae associated with severe aortic insufficiency: an interesting association causing myocardial ischemia.

BACKGROUND: Coronary artery fistula (CAF) is defined as a direct communication of a coronary artery with a cardiac chamber, great vessel or other vascular structure, bypassing the myocardial capillary bed. Congenital CAFs joining into the pulmonary artery are rare cardiac anomalies. CAFs arising from two coronary arteries are even more rare especially when combined with valvular heart disease. The coincidence of CAFs with aortic insufficiency is relatively rare and sometimes might cause myocardial ischemia. RESULTS: We present a case of bilateral coronary-pulmonary artery fistula combined with severe aortic insufficiency causing myocardial ischemia and who subsequently underwent fistula ligation during aortic valve surgery.