Lack of association between angiotensin-converting enzyme gene polymorphism and type I aortic dissection.

The relationship between angiotensin-converting enzyme (ACE) gene polymorphism and type I aortic dissection was examined in 205 unrelated hypertensives. A total of 94 patients underwent emergency repair due to type I aortic dissection, confirmed by computed tomography, and the remaining 111 were controls. Polymerase chain reaction was used to confirm that ACE gene polymorphism was due to insertion (I) or deletion (D) of a 287 base pair (bp) DNA sequence within intron 16. The genotype distribution and allele frequency of ACE I/D polymorphism between patients and controls were not statistically significant. When the frequency of at least one D allele carrier (DD or ID genotype) was compared with the II homozygous genotype, there was also no significant difference between the study groups. The findings revealed no association between ACE I/D polymorphism and aortic dissection. We conclude that I/D mutation of the ACE gene does not seem to be a risk factor for aortic dissection.

The determinants of systolic pulmonary venous flow reversal by transthoracic pulsed Doppler in mitral regurgitation: its value in determining the severity of regurgitation.

OBJECTIVE: Systolic pulmonary venous flow reversal (SPVFR) has been evaluated in mitral regurgitation (MR) primarily by transoesophageal echocardiography (TEE). There is limited study on the value of SPVFR obtained from transthoracic echocardiography (TTE) for the quantification of MR. In this study, determinants of SPVFR and the accuracy of SPVFR obtained with TTE in determining the severity of MR were investigated. METHODS AND RESULTS: Fifty patients with MR in whom reference quantitative Doppler evaluation was carried out formed the study group. Thirty-nine of them underwent cardiac catheterization. In all patients, SPVFR was evaluated by pulsed Doppler echo placed both at the right and left pulmonary vein in the apical four-chamber view. The SPVFR was present in 26 (52%) patients. Atrial fibrillation, and grade III-IV MR by catheterization were more frequent in patients who had SPVFR. Patients with SPVFR had increased values for regurgitant orifice area, regurgitant volume, regurgitant fraction, and left atrium/left ventricle diameters and volumes compared to patients without SPVFR. After multivariate analysis regurgitant fraction (RF) was the single and most powerful determinant of SPVFR (p<0.001). The SPVFR had high sensitivity, specificity and accuracy for the diagnosis of severe MR (89, 95 and 92%, respectively). CONCLUSION: It was concluded that SPVFR is a useful method for the evaluation of the severity of mitral regurgitation.

[Evaluation of dynamic left ventricular outflow tract obstruction by dobutamine stress echocardiography]. / Dinamik sol ventrikül çikis yolu obstrüksiyonlarinin dobutamin stres ekokardiyografi ile degerlendirilmesi.

OBJECTIVE: This study was planned to evaluate the dynamic left ventricular outflow tract (LVOT) obstruction by using dobutamine stress echocardiography (DSE) in patients with asymmetric septal hypertrophy and/or septal bulging, who have no signs of LVOT gradient detected by conventional echocardiography, with symptoms mimicking hypertrophic obstructive cardiomyopathy (HOCM). METHODS: In sixty-one consecutive patients referred to our echocardiography laboratory with HOCM pre-diagnosis, exercise dyspnea and limitation of exercise capacity were evaluated. DSE was performed in 31 patients who fulfilled the inclusion criteria. Patients were divided into two groups according to the degree of dynamic gradient increase above baseline values during stress-test (Group 1 < 30 mmHg, Group 2 > 30 mmHg). Left ventricular diameters, septum and posterior wall thicknesses, ejection fraction, LVOT and aortic root diameters, presence of septal bulging and systolic anterior motion (SAM) and degree of septal angulation were sought. RESULTS: There were no significant differences between groups by means of LV diameters, septum and posterior wall thicknesses, EF, LVOT and aortic root diameters, presence of septal bulging (p > 0.05); whereas there were significant differences in SAM and degree of septal angulation (p < 0.05 and p < 0.0001, respectively). Systolic anterior motion (r = 0.61, p < 0.0001) and degree of septal angulation (r = -0.71, p < 0.001) correlated significantly with the dynamic gradient increase. CONCLUSION: Presence of SAM and degree of septal angulation obtained by DSE are reliable parameters to determine dynamic LVOT obstruction in patients who have asymmetric septal hypertrophy and septal bulging with no gradient on LVOT by conventional echocardiography.

[The evaluation of the severity of mitral regurgitation using color Doppler echocardiographic methods]. / Renkli Doppler ekokardiyografi yöntemleri ile mitral yetersizligi ciddiyetinin degerlendirilmesi.

OBJECTIVE: This study was planned to assess the vena contracta (VC), flow convergence area (PISA) and jet area (JA) methods in evaluating the severity of mitral regurgitation (MR) and to test the accuracy of a proposed algorithm using these methods. METHODS: Eighty-seven patients with chronic MR were enrolled in the study. VC of < 0.3 cm, maximal MR flow rate calculated by PISA (Qmax) of < 72 cm3/sn and JA of < 4 cm2 were classified as mild MR. VC of > 0.5 cm, Qmax of > 240 cm3/sn and JA of > 8 cm2 were classified as severe MR. Whereas the values between these ranges were called to be moderate MR. The algorithm was planned as follows: In the first step, VC width was measured. If a patient has VC = 0.3-0.5 cm, it was used Qmax in the eccentric jets and JA in the central jets in the second step. The severity of MR were considered as severe, moderate and mild for > 50%, 21-49% and 20% of the regurgitant fraction calculated by the reference method (the quantitative Doppler method depending on aortic and mitral stroke volumes), respectively. RESULTS: The sensitivity of VC was low in differentiating between moderate and severe MR (63%). In eccentric jets, the regurgitant volume calculated by PISA was higher than that of reference method (70 +/- 49 vs. 59 +/- 29 cm3) and the JA was found to be less than that of central jets despite similar regurgitant fraction (6.8 +/- 3.2 vs. 8.5 +/- 3.3 cm2). The algorithm agreed well with the reference method and it was better than those of each tree methods (Cappa coefficients 0.89 vs. 0.65, 0.63 and 0.45 for VC, Qmax and JA; respectively). The accuracies of the algorithm in discriminating between mild and moderate MR or severe and non-severe MR were high (98% and 95%, respectively). CONCLUSIONS: The severity of MR can be determined accurately and simply by using VC, PISA and JA methods together.

Proximal isovelocity surface area (PISA) as a noninvasive method for the estimation of the shunt quantification in perimembranous ventricular septal defects.

This study was designed to assess the reliability of the proximal isovelocity surface area (PISA) method for the estimation of shunt quantification in perimembranous ventricular septal defects (PVSD). The study group was composed of 30 patients (age 11 +/- 7 years, 13 female) with PVSD. The shunt flow (Qp-Qs) and the ratio of the pulmonary flow to the systemic flow (Qp/Qs) were calculated by spectral Doppler and catheterization. The Qp-Qs, the defect area (DA), and the shunt volume (SV) were obtained by the PISA method. The PISA method estimated the DA (cm(2)/m(2)), the SV (cm(3)/m(2)), and the Qp-Qs (L/min/m(2)) to be equal to (2 x pi x R(2) x NL)/(V(max) x Body surface area), DA x TVI(shunt), and to SV x Heart rate, respectively (R is the distance of the maximal PISA from the first aliasing line to the left ventricular side of the defect, NL is the nyquist limit, and V(max) and TVI(shunt) are the peak velocity and time-velocity integral of transdefect Doppler tracing obtained by continuous-wave Doppler). The PISA method (3.4 +/- 1.5 L/min/m(2)) underestimated the Qp-Qs according to spectral Doppler (r = 0.96, P < 0.001; mean difference -0.74 +/- 0.61 L/min/m(2); SEE = 0.11 L/min/m(2), P < 0.001) and catheterization (r = 0.92, P < 0.001; mean difference -0.45 +/- 0.7 L/min/m(2); SEE = 0.13 L/min/m(2), P < 0.001). The correlations between the PISA findings (Qp-Qs, DA, SV) and the catheterization Qp/Qs (r = 0.86, 0.84, and 0.86; P < 0.001, respectively), or between these and the spectral Doppler Qp/Qs (r = 0.80, 0.80, and 0.79; P < 0.001, respectively) were significant. The accuracies of the PISA findings in identifying large defects were high (0.90, 0.93, and 0.90 for cut-off values of Qp-Qs = 3.67 L/min/m(2), DA = 0.44 cm(2)/m(2), and SV = 43 cm(3)/m(2), respectively). As a result, the PISA method can be a simple and reliable alternative to the spectral Doppler method in the identification of large shunts in PVSD.