Application of the vena contracta method for the calculation of the mitral valve area in mitral stenosis

OBJECTIVES: The vena contracta is the narrowest region of the regurgitant or stenotic jet just downstream the orifice and reflects the size of that orifice. This study was performed to assess the accuracy of the vena contracta width (VCW) in evaluating the severity of mitral stenosis (MS) and to compare the mitral valve area (MVA) determined by VCW with MVAs obtained by other more traditional echocardiographic methods. METHODS: We studied 59 patients (43 females, 42 +/- 14 years) with MS. VCW was measured in the apical four chamber view by Doppler color flow mapping. The largest diameter of the VCW during diastole was measured for at least three cardiac cycles and averaged. MVA was calculated from the following equation: pir(2), where r = VCW/2. MVA was also determined by planimetry, the pressure half-time method, and by the Gorlin formula. RESULTS: In this study, the width of the vena contracta ranged from 0.89 to 1.73 cm (mean 1.30 +/- 0.21). MVA, calculated based on the VCW, ranged from 0.63 to 2.35 cm(2) (mean 1.36 +/- 0.41). MVA by VCW (1.36 +/- 0.41 cm(2)) showed good correlations with three comparative techniques: (1) the cross-sectional area by planimetry (1.35 +/- 0.36 cm(2), mean difference = 0.21 +/- 0.16 cm(2), y = 0.91x + 0.14, r = 0.79, SEE = 0.26 cm(2), p < 0.001); (2) the area derived from the Doppler pressure half-time (1.27 +/- 0.32 cm(2), mean difference = 0.22 +/- 0.19 cm(2), y = 0.97x + 0.13, r = 0.76, SEE = 0.27 cm(2), p < 0.001), and (3) the area derived from the Gorlin equation in the 18 patients who underwent catheterization (1.27 +/- 0.35 cm(2), mean difference = 0.19 +/- 0.16, y = 0.98x + 0.05, r = 0.81, SEE = 0.26 cm(2), p < 0.001). CONCLUSIONS: These findings suggest that Doppler color flow imaging of the MS jet in the vena contracta can provide an accurate estimation of MVA and appears to be potentially applicable in the assessment of the severity of MS.     

Is the Change of Late Potential Over Time Related to Enzyme Levels?Ichemic Burden in Acute Myocardial Infarction

Background: The ventricular late potential (VLP) detected using the technique of signal average electrocardiography (SAECG) interacts with several factors, primarily time. Method: In this study, we examined the interaction, over time, of VLP with the initial ischemic burden and enzyme levels in acute myocardial infarction. Patients diagnosed as having acute myocardial infarction were included in the study. On the first day, the patients underwent enzyme analysis and electrocardiography (ECG) follow‐up every 6 hours. A 24‐hour ambulatory ECG was performed on the seventh day in order to determine the ischemic burden. SAECG findings (TQRS, RMS, LAS were obtained on the seventh day, in the first and third months. The study was continued with the patients who did not require angioplasty as decided with angiographic evaluation in the first month. Results: The study included 30 patients with acute myocardial infarction (mean age 51 ± 12, 28 males and 2 females). The initial mean CK‐MB levels and the mean ischemic burden were 98 ± 31 U/L and 44 ± 96 minutes. The TQRS (ms), LAS (ms), and RMS (μV) values (mean ± SD) obtained at day 7, month 1, and month 3 are 97 ± 12, 96 ± 9, 103 ± 11, P = 0.01; 31 ± 10, 31 ± 11, 32 ± 10, P = 0.46; 43 ± 28, 41 ± 26, 33 ± 25, P = 0.01, respectively. We observed that the TQRS and RMS values changed significantly with time, but these levels of significance disappeared when adjusted for the initial ischemic burden and CK‐MB levels (P = 0.06; P = 0.53). The VLP frequency was 33% at day 7 and 23% at month 3. Unlike the CK‐MB level, the initial ischemic burden was significantly different between the patients with and without VLP at month 3 (150.85 ± 149.28, 12.34 ± 26.48, P = 0.001). When tested together with age and gender, it was found that the high initial ischemic burden increased the possibility of VLP (OR: 24, Cl: 2.09–279.52, P = 0.01) at month 3. Conclusion: SAECG findings in patients with myocardial infarction changed with time; however, this change occurred depending on the initial ischemic burden and CK‐MB levels. Of these, only the initial ischemic burden, especially in high levels, was a determinant for the presence of VLP in the late period of myocardial infarction. A.N.E. 2002;7(3):242–246     

Primary conus medullaris arteriovenous shunt and secondary lumbo-sacral epidural arteriovenous fistula: One malformation can hide another

We report an anatomical-based association between conus medullaris pial arteriovenous shunt that drain caudally towards the lumbosacral area with very delayed onset of an acquired lumbar epidural shunt, draining secondarily towards intradural veins and responsible for a venous congestive myelopathy with identical clinical symptoms. These patients require close clinical and imaging follow-ups in order to propose adequate treatments before onset of irreversible neurological deficits. MRA should include the lumbo-sacral area in its field of view.     

Effects of laser modalities on shear bond strengths of composite superstructure to zirconia and PEEK infrastructures: an in vitro study

Odontology - In the last decade, demand for metal-free esthetic restorations has grown considerably due to the development of materials to fulfill the need for an esthetic prosthesis. We examined...     

Effects of levothyroxine treatment on insulin sensitivity,endothelial function and risk factors of atherosclerosis in hypothyroid women

Objectives

Contradictory results are encountered in literature regarding the effects of hypothyroidism on the risk factors of atherosclerosis. We aimed to explore the changes in atherosclerotic risk factors and insulin sensitivity before and after levothyroxine replacement therapy in women with primary hypothyroidism and compare with that of healthy controls.

Patients and methods

Twelve patients (mean age of 34 ± 11.7 years) without an evident disease except for primary hypothyroidism (TSH ≥ 20 mIU/L) and eleven euthyroid, age-matched (33.8 ± 8.4 years) female volunteers as controls were included. Baseline thyroid hormones, lipid parameters, homocysteine, fibrinogen levels were measured in both groups. Flow-mediated endothelial-dependent vasodilatation (FMD) method was used to evaluate endothelial dysfunction. Insulin sensitivity was assessed by M values based on euglycemic hyperinsulinemic clamp technique. The same measurements were performed after 6 months of levothyroxine treatment and recovery of euthyroid state in hypothyroid patients.

Results

Treatment reduced total cholesterol (P < 0.005), LDL-cholesterol (P < 0.005), lipoprotein(a) (P < 0.01), fibrinogen (P < 0.0001) and homocysteine (P < 0.0005) levels. Treatment significantly improved M values of hypothyroid patients (3.68 ± 1.53 mg/kg.min vs 6.02 ± 1.21 mg/kg.min, P < 0.0001) and FMD (9.1 ± 3.7% vs 16.4 ± 4.4%, hypothyroid vs euthyroid, P < 0.0001). Significant correlations were found between M values and TSH (r = −0.6, P < 0.005), fibrinogen (r = −0.53, P < 0.01) measurements, free T3 (r = 0.51, P < 0.02) and free T4 (r = 0.49, P < 0.02) levels. FMD was significantly correlated with fibrinogen levels (r = −0.49, P < 0.05).

Conclusion

Insulin resistance, endothelial dysfunction, atherosclerotic risk markers improves with treatment of hypothyroidism.     

Prognostic value of uric acid in patients with ST-elevated myocardial infarction undergoing primary coronary intervention

Elevated uric acid (UA) levels have been associated with cardiovascular disease in epidemiologic studies. The relation between UA levels and long-term outcomes in patients with ST-segment elevation myocardial infarction who undergo primary percutaneous coronary intervention is not known. Data from 2,249 consecutive patients with ST-segment elevation myocardial infarction who underwent primary percutaneous coronary intervention were evaluated. Patients were divided into 2 groups with high or low UA using upper limits of normal of 6 mg/dl for women and 7 mg/dl for men. There were 1,643 patients in the low-UA group (mean age 55.9 ± 11.6 years, 85% men) and 606 patients in the high-UA group (mean age 60.5 ± 12.6 years, 76% men). Serum UA levels were 8.0 ± 1.5 mg/dl in the high-UA group and 5.2 ± 1.0 mg/dl in the low-UA group (p <0.001). The in-hospital mortality rate was significantly higher in patients with high UA levels (9% vs 2%, p <0.001), as was the rate of adverse outcomes in patients with high UA. The mean follow-up time was 24.3 months. Cardiovascular mortality, reinfarction, target vessel revascularization, heart failure, and major adverse cardiac events were all significantly higher in the high-UA group. In a multivariate analyses, high plasma UA levels were an independent predictor of major adverse cardiac events in the hospital (odds ratio 2.03, 95% confidence interval 1.25 to 3.75, p = 0.006) and during long-term follow-up (odds ratio 1.64, 95% confidence interval 1.05 to 2.56, p = 0.03). In conclusion, high UA levels on admission are independently associated with in-hospital and long-term adverse outcomes in patients with ST-segment elevation myocardial infarction who undergo primary percutaneous coronary intervention.