Which method should be used to determine the obesity, in patients with coronary artery disease? (body mass index, waist circumference or waist-hip ratio).

OBJECTIVE: To determine body mass index (BMI), waist circumference and waist-hip ratio (WHR) in cases with angiographically established coronary artery disease (CAD) and to compare the obesity degrees established according to the ranges determined by the International Guidelines Committees for BMI, waist circumference and WHR. DESIGN: Cross-sectional, observational study. SUBJECTS: A total of 617 consecutive cases (516 males, mean age: 57.2+/-10.8 y) with CAD who underwent their first coronary angiography between January 2000 and May 2000. MEASUREMENTS: Before coronary angiography, their heights, weights, waist and hip circumferences were measured. Waist circumferences, BMI and WHRs were compared both as a whole and also within stratified groups as for sexes and age groups categorized in decades above 40 y of age. RESULTS: Overweight cases comprised approximately half of the patients in both sexes. In males, the percentages of obese cases with respect to BMIs were 15%, while males with action level 2 waist circumferences were detected to be 20%. Obese male patients whose WHRs were >or=0.95 were found to be 51%. In female cases, corresponding percentages of obesity were estimated to be 32, 72 and 86%, respectively. CONCLUSION: In the same patient groups, the prevalence of obesity, defined by BMI, waist circumference and WHR, could vary three-fold. Thus, some patients may not display a diagnosis of obesity. To prevent this possibility the waist circumference is an easy method, which reflects central obesity more accurately.

Exercise electrocardiography test in patients with aortic stenosis. Differential features from that of coronary artery disease.

BACKGROUND AND AIM OF THE STUDY: Studies that have been conducted with an exercise test in patients with aortic stenosis (AS) have demonstrated that results of an exercise test can mimic that of coronary artery disease (CAD). The objective of our study was to investigate if there was any differential feature(s) of an exercise test in patients with AS compared to those with CAD. METHODS: We prospectively studied 42 patients with AS (AS group, age 37 +/- 23, range 8-75) with an averaged maximal gradient of 42 +/- 19 mmHg (range 26-95). All patients had undergone a coronary angiography within 1 week of the exercise test and none had CAD. Another 100 patients with CAD, diagnosis proven with coronary angiography, comprised our second group for the comparison (CAD group). Cornell protocol was used in all patients. RESULTS: ST-segment depression was observed in all patients (160 +/- 25 microV in AS group and 170 +/- 20 microV in CAD group, P>0.05). Thirty-four (81%) patients in AS group and 88 (88%) patients in CAD group exceeded the classical threshold for the test positivity (P>0.05). ST/HR slopes derived from heart rate adjustment to ST-segment level did not differ between the study groups (3.2 +/- 2.3 and 3.7 +/- 2.2 microV/beat/min, in AS and CAD groups, respectively, P>0.05). Recovery-phase patterns of ST-segment in heart rate domain were quite different between AS and CAD (clockwise loop: 86% vs. 0%; counterclockwise loop: 9% vs. 88% in AS group and CAD group, respectively, both P<0.0001). Percentage of intermediate loop was 5% in AS group and 12% in CAD group (P>0.05). CONCLUSIONS: Our study demonstrated that patients with AS could be distinguished from those with CAD with the method of rate-recovery loop analysis.

Microbubbles associated with mechanical heart valves: their relationwith serum lactic dehydrogenase levels.

BACKGROUND: There has been no consensus about the prevalence and mechanism of generation of microbubbles in mechanical prosthetic heart valves (PHV). The aim of this study was to determine the prevalence of microbubbles in PHV and their relation to serum lactic dehydrogenase (LDH) levels. METHODS AND RESULTS: We prospectively studied 150 normally functioning mitral PHV (98 bileaflet and 52 monoleaflet) in 150 patients with the use of transesophageal echocardiography with a multiplane 5-MHz probe. None of the patients had an aortic prosthetic valve. Blood was drawn to determine serum LDH level. None of the patients had any factors that might affect the LDH level other than the PHV-related hemolysis. Patients with spontaneous echo contrast in the left atrium that might affect the assessment of the microbubbles were excluded. We devised a method to determine the amount of microbubbles for each PHV. Microbubbles were detected in 118 (79%) of 150 PHV, including 97 (99%) of 98 bileaflet valves and 21 (40%) of 52 monoleaflet (tilting disk) valves (P <. 0001). Intraobserver variability was not statistically significant for the determination of the amount of microbubbles (z = 1.7, P =. 08). There was a strong correlation between serum LDH levels and the amount of microbubbles (rs = 0.69, P <.001). CONCLUSIONS: Microbubbles were detected in more patients than reported previously. They were found to be associated more with the bileaflet than the monoleaflet PHV. Sorin monoleaflet valves were associated with microbubbles significantly less often than the others. There was a strong correlation between serum LDH levels and microbubble counts, which suggests that hemolysis may be related to microbubble formation.

High prevalence of hypercoagulable states in patients with recurrent thrombosis of mechanical heart valves.

BACKGROUND AND AIMS OF THE STUDY: Thrombosis is one of the most feared and life-threatening complications of mechanical heart valves (MHV), with an incidence of 1-3 per 100 patient-years. Hypercoagulable states are highly prevalent in the general population and can predispose MHV to thrombus formation. Thus, we conducted a study to investigate the frequency of hypercoagulable states in patients with MHV who had recurrent thrombosis at least twice after valve implantation. METHODS: Fifteen patients (mean age 42 +/- 11 years; range: 18 to 55 years) with recurrent thrombosis of MHV (2.4 +/- 0.8 recurrences/patient) (group 1) and 15 matched patients (mean age 40 +/- 12 years; range: 18 to 55 years) with MHV without thrombosis (group 2) were followed up with transthoracic and transesophageal echocardiography. Patients' sera were monitored for antibodies to cardiolipin (ACLA-IgG and ACLA-IgM), phosphatidylserine (APSA), lupus-type anticoagulant (LA) and lipoprotein(a) (LP(a)). RESULTS: Average values for group 1 versus group 2 were: ACLA-IgG (normal range < 15 GPLU/ml) 24.7 +/- 14.6 versus 6.2 +/- 2.7 (p < 0.001); ACLA-IgM (< 12.5 MPLU/ml) 7.9 +/- 5.0 versus 3.3 +/- 1.7 (u = 185; p < 0.001); APSA (< 12 RLU/ml) 4.8 +/- 5.7 and 2.9 +/- 1.2 (p = 0.56); and LP(a) (< 30 mg/dl) 36.5 +/- 26.5 and 13.4 +/- 7.1 (p < 0.001). The frequency of LA-positive cases was 4/15 in group 1 and 0/15 in group 2 (p > 0.05). The frequency of abnormally high levels of ACLA-IgG was 9/15 in group 1 and 0/15 in group 2 (p < 0.001); of ACLA-IgM, 2/15 in group 1 and 0/15 in group 2 (p > 0.05); of APSA, 1/15 in group 1 and 0/15 in group 2 (p > 0.05); and of LP(a), 5/15 in group 1 and 0/15 in group 2 (p < 0.05). At least one of the factors included in this study was abnormal in 14 of 15 (93%) patients (p < 0.0001). CONCLUSIONS: Hypercoagulable states are highly prevalent in patients with recurrent thrombosis of MHV. All patients evaluated for therapy of obstructive thrombosis of MHV should be investigated for hypercoagulable state. Moreover, in high-risk patients, surgical replacement of the MHV with a bioprosthesis should be considered.

Contrast echoes detected during percutaneous mitral balloon commissurotomy with Inoue balloons and their relation to cerebral microembolic signals.

The aim of this study was to find out the mechanism of genesis of contrast echoes detected with echocardiography during percutaneous mitral balloon commissurotomy (PMBC) procedures with Inoue balloons and to assess their association with cerebral microembolic signals with transcranial Doppler examinations. Ten Inoue balloons (Toray Instruments) were used in 10 patients (mean age 36 +/- 10 years). In all patients transesophageal echocardiographies with a multiplane 5 MHz probe were performed immediately before and during the PMBC procedure. None of the patients had left atrial thrombus during the PMBC. All of the balloons were inflated within the left atriums and left ventricles and were tested in saline to see whether there was a visible air leak after the PMBC procedures. Transcranial Doppler examinations were done with 2 MHz probes from the middle cerebral artery. Contrast echoes were detected in all patients during inflation and/or deflation, independent of the intracardiac sites. After a few cardiac cycles there was a very intense shower of microembolic signals detected with the transcranial Doppler examination, which persisted for all inflations and/or deflations. All balloons yielded visible air leaks from the two small holes at the waist of the balloons in saline. There were a few contrast echoes recorded in some of the patients during the exchange of equipment, and one patient had a transient neurologic and coronary ischemic event following the introduction of the stretcher tube of the Inoue balloon. Intracardiac contrast echoes and transcranial microembolic signals during the PMBC procedure were detected in all PMBC procedures and were due to air that was entrapped between the two latex layers of the Inoue balloons and air introduced from outside during the exchange of the equipment.

Application of proximal isovelocity surface area method to determine prosthetic mitral valve area.

BACKGROUND: In this study, we investigated the accuracy of orifice area determination of the prosthetic valve (Biocor) by using proximal isovelocity surface area method (PISA). Thirty-two patients (26 women, 6 men; mean age 44 +/- 8.1 years) were studied. Eleven patients were in normal sinus rhythm and the rest were in atrial fibrillation. Associated valvular lesions were mild aortic regurgitation in 12 patients and moderate tricuspid regurgitation in 19 patients. Sizes of prosthetic valves were 27 to 31, and implantation duration was 4 to 8 years. METHODS AND RESULTS: We analyzed the flow convergence zone proximal to the valve orifice with the concept of a hemispheric model. Mitral valve area (MVA) calculation was formulated by MVA = 2pi r2 x Va/Vm x (Vm/Vm-Va), where Vm is the maximal mitral velocity and Vm/Vm - Va is a correction factor to account for flattening of isotachs near the prosthetic orifice. MVA calculations by PISA were compared with pressure half-time (PHT), continuity equation (CONT), and color flow area (CFA) methods. Mitral valve areas were 2.17 +/- 0.17 cm2, 2.22 +/- 0.21 cm2, 2.19 +/- 0.22 cm2, and 2.16 +/- 0.17 cm2 in PISA, CFA, PHT, and CONT methods, respectively. Values in the comparison of MVA measurements by different methods were PISA vs PHT, r =.86; PISA vs CFA, r =.77; and PISA vs CONT, r =.89. CONCLUSIONS: The PISA method gives reliable estimates of large orifices such as prosthetic valves. Although the best correlation was seen with the CONT method, results of this study also confirmed that the PISA method can be applied with reasonable accuracy.

Prevalence of microbubbles associated with mechanical prosthetic cardiac valves: a prospective transesophageal echocardiography study.

BACKGROUND AND AIM OF THE STUDY: The study aim was to identify the prevalence of microbubbles in different types of mechanical cardiac valve and, if feasible, to associate microbubbles with various clinical conditions, including thrombotic occlusion of the valves. METHODS: A total of 153 mechanical prosthetic valves were studied (58 aortic, 95 mitral) in 140 patients, prospectively. All valves were functioning normally. In addition, eight mitral prosthetic valves were selected without microbubbles and with an obstructive valvular thrombosis that had undergone successful thrombolysis (group 1); a further eight patients with unsuccessful thrombolysis (group 2) were studied by transesophageal echocardiography before and after thrombolytic therapy. RESULTS: Microbubbles were detected in 75% (114/153) of prosthetic valves, 99% (88/89) of bileaflet valves, and 45% (29/64) of monoleaflet valves (p < 0.0001). Only 14% (4/28) of Sorin monoleaflet valves were associated with microbubbles, which is distinctively less than other valves (p < 0.001 for each); 71% and 77% of aortic and mitral prosthetic valves, respectively, were associated with microbubbles (p = NS). Prosthetic valves with an obstructive thrombosis and no microbubbles in group 1 showed new appearance of microbubbles in 88% (7/8) of cases after successful thrombolysis. Absence of microbubbles in group 2 persisted in all eight patients at the second examination. CONCLUSIONS: Microbubbles were detected in a greater proportion of patients than reported previously and were found to be associated more with bileaflet prosthetic heart valves than with monoleaflet valves. Sorin monoleaflet valves were associated with microbubbles dramatically less than all other valves. The new appearance of microbubbles after thrombolytic therapy of mechanical prosthetic heart valves with an obstructive thrombosis may indicate successful thrombolysis.

Validation of flow convergence region method in assessing mitral valve area in the course of transthoracic and transesophageal echocardiographic studies.

The purpose of this study was to determine the diagnostic value of flow convergence region method (FCR) to complement well-accepted techniques in assessing mitral valve area (MVA). Fifty-three patients (39 women, 14 men) were enrolled in the study. Transesophageal echocardiography (TEE) was performed after transthoracic echocardiographic (TTE) evaluation, and all measurements were performed for each patient. Mean MVA values determined by different methods both in TEE and TTE studies did not differ (p = not significant). In 51 (96%) patients, TEE and TTE were feasible and measurements of MVA with FCR correlated well with the conventional methods (r = 0.87, standard error of the estimate = 0.13 cm2). In TEE, MVA determined by FCR also correlated well with that obtained by the "pressure half time" method (r = 0.90, standard error of the estimate = 0.11 cm2). Results of our study confirmed the feasibility and accuracy of FCR. Because TEE provides reliable estimation of MVA by FCR, intraoperative monitoring by TEE should be considered as a comparative alternative method.